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v4.17
   1/*
   2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
   3 * All Rights Reserved.
   4 *
   5 * This program is free software; you can redistribute it and/or
   6 * modify it under the terms of the GNU General Public License as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it would be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write the Free Software Foundation,
  16 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18#include "xfs.h"
  19#include "xfs_fs.h"
  20#include "xfs_shared.h"
  21#include "xfs_format.h"
  22#include "xfs_log_format.h"
  23#include "xfs_trans_resv.h"
  24#include "xfs_bit.h"
  25#include "xfs_sb.h"
  26#include "xfs_mount.h"
  27#include "xfs_defer.h"
  28#include "xfs_da_format.h"
  29#include "xfs_da_btree.h"
  30#include "xfs_inode.h"
  31#include "xfs_trans.h"
  32#include "xfs_log.h"
  33#include "xfs_log_priv.h"
  34#include "xfs_log_recover.h"
  35#include "xfs_inode_item.h"
  36#include "xfs_extfree_item.h"
  37#include "xfs_trans_priv.h"
  38#include "xfs_alloc.h"
  39#include "xfs_ialloc.h"
  40#include "xfs_quota.h"
  41#include "xfs_cksum.h"
  42#include "xfs_trace.h"
  43#include "xfs_icache.h"
  44#include "xfs_bmap_btree.h"
  45#include "xfs_error.h"
  46#include "xfs_dir2.h"
  47#include "xfs_rmap_item.h"
  48#include "xfs_buf_item.h"
  49#include "xfs_refcount_item.h"
  50#include "xfs_bmap_item.h"
  51
  52#define BLK_AVG(blk1, blk2)	((blk1+blk2) >> 1)
  53
  54STATIC int
  55xlog_find_zeroed(
  56	struct xlog	*,
  57	xfs_daddr_t	*);
  58STATIC int
  59xlog_clear_stale_blocks(
  60	struct xlog	*,
  61	xfs_lsn_t);
  62#if defined(DEBUG)
  63STATIC void
  64xlog_recover_check_summary(
  65	struct xlog *);
  66#else
  67#define	xlog_recover_check_summary(log)
  68#endif
  69STATIC int
  70xlog_do_recovery_pass(
  71        struct xlog *, xfs_daddr_t, xfs_daddr_t, int, xfs_daddr_t *);
  72
  73/*
  74 * This structure is used during recovery to record the buf log items which
  75 * have been canceled and should not be replayed.
  76 */
  77struct xfs_buf_cancel {
  78	xfs_daddr_t		bc_blkno;
  79	uint			bc_len;
  80	int			bc_refcount;
  81	struct list_head	bc_list;
  82};
  83
  84/*
  85 * Sector aligned buffer routines for buffer create/read/write/access
  86 */
  87
  88/*
  89 * Verify the log-relative block number and length in basic blocks are valid for
  90 * an operation involving the given XFS log buffer. Returns true if the fields
  91 * are valid, false otherwise.
  92 */
  93static inline bool
  94xlog_verify_bp(
 
  95	struct xlog	*log,
  96	xfs_daddr_t	blk_no,
  97	int		bbcount)
  98{
  99	if (blk_no < 0 || blk_no >= log->l_logBBsize)
 100		return false;
 101	if (bbcount <= 0 || (blk_no + bbcount) > log->l_logBBsize)
 102		return false;
 103	return true;
 104}
 105
 106/*
 107 * Allocate a buffer to hold log data.  The buffer needs to be able
 108 * to map to a range of nbblks basic blocks at any valid (basic
 109 * block) offset within the log.
 110 */
 111STATIC xfs_buf_t *
 112xlog_get_bp(
 113	struct xlog	*log,
 114	int		nbblks)
 115{
 116	struct xfs_buf	*bp;
 117
 118	/*
 119	 * Pass log block 0 since we don't have an addr yet, buffer will be
 120	 * verified on read.
 121	 */
 122	if (!xlog_verify_bp(log, 0, nbblks)) {
 123		xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer",
 124			nbblks);
 125		XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
 126		return NULL;
 127	}
 128
 129	/*
 130	 * We do log I/O in units of log sectors (a power-of-2
 131	 * multiple of the basic block size), so we round up the
 132	 * requested size to accommodate the basic blocks required
 133	 * for complete log sectors.
 134	 *
 135	 * In addition, the buffer may be used for a non-sector-
 136	 * aligned block offset, in which case an I/O of the
 137	 * requested size could extend beyond the end of the
 138	 * buffer.  If the requested size is only 1 basic block it
 139	 * will never straddle a sector boundary, so this won't be
 140	 * an issue.  Nor will this be a problem if the log I/O is
 141	 * done in basic blocks (sector size 1).  But otherwise we
 142	 * extend the buffer by one extra log sector to ensure
 143	 * there's space to accommodate this possibility.
 144	 */
 145	if (nbblks > 1 && log->l_sectBBsize > 1)
 146		nbblks += log->l_sectBBsize;
 147	nbblks = round_up(nbblks, log->l_sectBBsize);
 148
 149	bp = xfs_buf_get_uncached(log->l_mp->m_logdev_targp, nbblks, 0);
 150	if (bp)
 151		xfs_buf_unlock(bp);
 152	return bp;
 153}
 154
 155STATIC void
 156xlog_put_bp(
 157	xfs_buf_t	*bp)
 158{
 159	xfs_buf_free(bp);
 160}
 161
 162/*
 163 * Return the address of the start of the given block number's data
 164 * in a log buffer.  The buffer covers a log sector-aligned region.
 165 */
 166STATIC char *
 167xlog_align(
 168	struct xlog	*log,
 169	xfs_daddr_t	blk_no,
 170	int		nbblks,
 171	struct xfs_buf	*bp)
 172{
 173	xfs_daddr_t	offset = blk_no & ((xfs_daddr_t)log->l_sectBBsize - 1);
 174
 175	ASSERT(offset + nbblks <= bp->b_length);
 176	return bp->b_addr + BBTOB(offset);
 177}
 178
 179
 180/*
 181 * nbblks should be uint, but oh well.  Just want to catch that 32-bit length.
 182 */
 183STATIC int
 184xlog_bread_noalign(
 185	struct xlog	*log,
 186	xfs_daddr_t	blk_no,
 187	int		nbblks,
 188	struct xfs_buf	*bp)
 189{
 190	int		error;
 191
 192	if (!xlog_verify_bp(log, blk_no, nbblks)) {
 193		xfs_warn(log->l_mp,
 194			 "Invalid log block/length (0x%llx, 0x%x) for buffer",
 195			 blk_no, nbblks);
 196		XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
 197		return -EFSCORRUPTED;
 198	}
 199
 200	blk_no = round_down(blk_no, log->l_sectBBsize);
 201	nbblks = round_up(nbblks, log->l_sectBBsize);
 202
 203	ASSERT(nbblks > 0);
 204	ASSERT(nbblks <= bp->b_length);
 205
 206	XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no);
 207	bp->b_flags |= XBF_READ;
 208	bp->b_io_length = nbblks;
 209	bp->b_error = 0;
 210
 211	error = xfs_buf_submit_wait(bp);
 212	if (error && !XFS_FORCED_SHUTDOWN(log->l_mp))
 213		xfs_buf_ioerror_alert(bp, __func__);
 214	return error;
 215}
 216
 217STATIC int
 218xlog_bread(
 219	struct xlog	*log,
 220	xfs_daddr_t	blk_no,
 221	int		nbblks,
 222	struct xfs_buf	*bp,
 223	char		**offset)
 224{
 225	int		error;
 226
 227	error = xlog_bread_noalign(log, blk_no, nbblks, bp);
 228	if (error)
 229		return error;
 230
 231	*offset = xlog_align(log, blk_no, nbblks, bp);
 232	return 0;
 233}
 234
 235/*
 236 * Read at an offset into the buffer. Returns with the buffer in it's original
 237 * state regardless of the result of the read.
 238 */
 239STATIC int
 240xlog_bread_offset(
 241	struct xlog	*log,
 242	xfs_daddr_t	blk_no,		/* block to read from */
 243	int		nbblks,		/* blocks to read */
 244	struct xfs_buf	*bp,
 245	char		*offset)
 246{
 247	char		*orig_offset = bp->b_addr;
 248	int		orig_len = BBTOB(bp->b_length);
 249	int		error, error2;
 250
 251	error = xfs_buf_associate_memory(bp, offset, BBTOB(nbblks));
 252	if (error)
 253		return error;
 254
 255	error = xlog_bread_noalign(log, blk_no, nbblks, bp);
 256
 257	/* must reset buffer pointer even on error */
 258	error2 = xfs_buf_associate_memory(bp, orig_offset, orig_len);
 259	if (error)
 260		return error;
 261	return error2;
 262}
 263
 264/*
 265 * Write out the buffer at the given block for the given number of blocks.
 266 * The buffer is kept locked across the write and is returned locked.
 267 * This can only be used for synchronous log writes.
 268 */
 269STATIC int
 270xlog_bwrite(
 271	struct xlog	*log,
 272	xfs_daddr_t	blk_no,
 273	int		nbblks,
 274	struct xfs_buf	*bp)
 275{
 276	int		error;
 277
 278	if (!xlog_verify_bp(log, blk_no, nbblks)) {
 279		xfs_warn(log->l_mp,
 280			 "Invalid log block/length (0x%llx, 0x%x) for buffer",
 281			 blk_no, nbblks);
 282		XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
 283		return -EFSCORRUPTED;
 284	}
 285
 286	blk_no = round_down(blk_no, log->l_sectBBsize);
 287	nbblks = round_up(nbblks, log->l_sectBBsize);
 288
 289	ASSERT(nbblks > 0);
 290	ASSERT(nbblks <= bp->b_length);
 291
 292	XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no);
 293	xfs_buf_hold(bp);
 294	xfs_buf_lock(bp);
 295	bp->b_io_length = nbblks;
 296	bp->b_error = 0;
 297
 298	error = xfs_bwrite(bp);
 299	if (error)
 300		xfs_buf_ioerror_alert(bp, __func__);
 301	xfs_buf_relse(bp);
 302	return error;
 303}
 304
 305#ifdef DEBUG
 306/*
 307 * dump debug superblock and log record information
 308 */
 309STATIC void
 310xlog_header_check_dump(
 311	xfs_mount_t		*mp,
 312	xlog_rec_header_t	*head)
 313{
 314	xfs_debug(mp, "%s:  SB : uuid = %pU, fmt = %d",
 315		__func__, &mp->m_sb.sb_uuid, XLOG_FMT);
 316	xfs_debug(mp, "    log : uuid = %pU, fmt = %d",
 317		&head->h_fs_uuid, be32_to_cpu(head->h_fmt));
 318}
 319#else
 320#define xlog_header_check_dump(mp, head)
 321#endif
 322
 323/*
 324 * check log record header for recovery
 325 */
 326STATIC int
 327xlog_header_check_recover(
 328	xfs_mount_t		*mp,
 329	xlog_rec_header_t	*head)
 330{
 331	ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM));
 332
 333	/*
 334	 * IRIX doesn't write the h_fmt field and leaves it zeroed
 335	 * (XLOG_FMT_UNKNOWN). This stops us from trying to recover
 336	 * a dirty log created in IRIX.
 337	 */
 338	if (unlikely(head->h_fmt != cpu_to_be32(XLOG_FMT))) {
 339		xfs_warn(mp,
 340	"dirty log written in incompatible format - can't recover");
 341		xlog_header_check_dump(mp, head);
 342		XFS_ERROR_REPORT("xlog_header_check_recover(1)",
 343				 XFS_ERRLEVEL_HIGH, mp);
 344		return -EFSCORRUPTED;
 345	} else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) {
 346		xfs_warn(mp,
 347	"dirty log entry has mismatched uuid - can't recover");
 348		xlog_header_check_dump(mp, head);
 349		XFS_ERROR_REPORT("xlog_header_check_recover(2)",
 350				 XFS_ERRLEVEL_HIGH, mp);
 351		return -EFSCORRUPTED;
 352	}
 353	return 0;
 354}
 355
 356/*
 357 * read the head block of the log and check the header
 358 */
 359STATIC int
 360xlog_header_check_mount(
 361	xfs_mount_t		*mp,
 362	xlog_rec_header_t	*head)
 363{
 364	ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM));
 365
 366	if (uuid_is_null(&head->h_fs_uuid)) {
 367		/*
 368		 * IRIX doesn't write the h_fs_uuid or h_fmt fields. If
 369		 * h_fs_uuid is null, we assume this log was last mounted
 370		 * by IRIX and continue.
 371		 */
 372		xfs_warn(mp, "null uuid in log - IRIX style log");
 373	} else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) {
 374		xfs_warn(mp, "log has mismatched uuid - can't recover");
 375		xlog_header_check_dump(mp, head);
 376		XFS_ERROR_REPORT("xlog_header_check_mount",
 377				 XFS_ERRLEVEL_HIGH, mp);
 378		return -EFSCORRUPTED;
 379	}
 380	return 0;
 381}
 382
 383STATIC void
 384xlog_recover_iodone(
 385	struct xfs_buf	*bp)
 386{
 387	if (bp->b_error) {
 388		/*
 389		 * We're not going to bother about retrying
 390		 * this during recovery. One strike!
 391		 */
 392		if (!XFS_FORCED_SHUTDOWN(bp->b_target->bt_mount)) {
 393			xfs_buf_ioerror_alert(bp, __func__);
 394			xfs_force_shutdown(bp->b_target->bt_mount,
 395						SHUTDOWN_META_IO_ERROR);
 396		}
 397	}
 398
 399	/*
 400	 * On v5 supers, a bli could be attached to update the metadata LSN.
 401	 * Clean it up.
 402	 */
 403	if (bp->b_log_item)
 404		xfs_buf_item_relse(bp);
 405	ASSERT(bp->b_log_item == NULL);
 406
 407	bp->b_iodone = NULL;
 408	xfs_buf_ioend(bp);
 409}
 410
 411/*
 412 * This routine finds (to an approximation) the first block in the physical
 413 * log which contains the given cycle.  It uses a binary search algorithm.
 414 * Note that the algorithm can not be perfect because the disk will not
 415 * necessarily be perfect.
 416 */
 417STATIC int
 418xlog_find_cycle_start(
 419	struct xlog	*log,
 420	struct xfs_buf	*bp,
 421	xfs_daddr_t	first_blk,
 422	xfs_daddr_t	*last_blk,
 423	uint		cycle)
 424{
 425	char		*offset;
 426	xfs_daddr_t	mid_blk;
 427	xfs_daddr_t	end_blk;
 428	uint		mid_cycle;
 429	int		error;
 430
 431	end_blk = *last_blk;
 432	mid_blk = BLK_AVG(first_blk, end_blk);
 433	while (mid_blk != first_blk && mid_blk != end_blk) {
 434		error = xlog_bread(log, mid_blk, 1, bp, &offset);
 435		if (error)
 436			return error;
 437		mid_cycle = xlog_get_cycle(offset);
 438		if (mid_cycle == cycle)
 439			end_blk = mid_blk;   /* last_half_cycle == mid_cycle */
 440		else
 441			first_blk = mid_blk; /* first_half_cycle == mid_cycle */
 442		mid_blk = BLK_AVG(first_blk, end_blk);
 443	}
 444	ASSERT((mid_blk == first_blk && mid_blk+1 == end_blk) ||
 445	       (mid_blk == end_blk && mid_blk-1 == first_blk));
 446
 447	*last_blk = end_blk;
 448
 449	return 0;
 450}
 451
 452/*
 453 * Check that a range of blocks does not contain stop_on_cycle_no.
 454 * Fill in *new_blk with the block offset where such a block is
 455 * found, or with -1 (an invalid block number) if there is no such
 456 * block in the range.  The scan needs to occur from front to back
 457 * and the pointer into the region must be updated since a later
 458 * routine will need to perform another test.
 459 */
 460STATIC int
 461xlog_find_verify_cycle(
 462	struct xlog	*log,
 463	xfs_daddr_t	start_blk,
 464	int		nbblks,
 465	uint		stop_on_cycle_no,
 466	xfs_daddr_t	*new_blk)
 467{
 468	xfs_daddr_t	i, j;
 469	uint		cycle;
 470	xfs_buf_t	*bp;
 471	xfs_daddr_t	bufblks;
 472	char		*buf = NULL;
 473	int		error = 0;
 474
 475	/*
 476	 * Greedily allocate a buffer big enough to handle the full
 477	 * range of basic blocks we'll be examining.  If that fails,
 478	 * try a smaller size.  We need to be able to read at least
 479	 * a log sector, or we're out of luck.
 480	 */
 481	bufblks = 1 << ffs(nbblks);
 482	while (bufblks > log->l_logBBsize)
 483		bufblks >>= 1;
 484	while (!(bp = xlog_get_bp(log, bufblks))) {
 485		bufblks >>= 1;
 486		if (bufblks < log->l_sectBBsize)
 487			return -ENOMEM;
 488	}
 489
 490	for (i = start_blk; i < start_blk + nbblks; i += bufblks) {
 491		int	bcount;
 492
 493		bcount = min(bufblks, (start_blk + nbblks - i));
 494
 495		error = xlog_bread(log, i, bcount, bp, &buf);
 496		if (error)
 497			goto out;
 498
 499		for (j = 0; j < bcount; j++) {
 500			cycle = xlog_get_cycle(buf);
 501			if (cycle == stop_on_cycle_no) {
 502				*new_blk = i+j;
 503				goto out;
 504			}
 505
 506			buf += BBSIZE;
 507		}
 508	}
 509
 510	*new_blk = -1;
 511
 512out:
 513	xlog_put_bp(bp);
 514	return error;
 515}
 516
 517/*
 518 * Potentially backup over partial log record write.
 519 *
 520 * In the typical case, last_blk is the number of the block directly after
 521 * a good log record.  Therefore, we subtract one to get the block number
 522 * of the last block in the given buffer.  extra_bblks contains the number
 523 * of blocks we would have read on a previous read.  This happens when the
 524 * last log record is split over the end of the physical log.
 525 *
 526 * extra_bblks is the number of blocks potentially verified on a previous
 527 * call to this routine.
 528 */
 529STATIC int
 530xlog_find_verify_log_record(
 531	struct xlog		*log,
 532	xfs_daddr_t		start_blk,
 533	xfs_daddr_t		*last_blk,
 534	int			extra_bblks)
 535{
 536	xfs_daddr_t		i;
 537	xfs_buf_t		*bp;
 538	char			*offset = NULL;
 539	xlog_rec_header_t	*head = NULL;
 540	int			error = 0;
 541	int			smallmem = 0;
 542	int			num_blks = *last_blk - start_blk;
 543	int			xhdrs;
 544
 545	ASSERT(start_blk != 0 || *last_blk != start_blk);
 546
 547	if (!(bp = xlog_get_bp(log, num_blks))) {
 548		if (!(bp = xlog_get_bp(log, 1)))
 549			return -ENOMEM;
 550		smallmem = 1;
 551	} else {
 552		error = xlog_bread(log, start_blk, num_blks, bp, &offset);
 553		if (error)
 554			goto out;
 555		offset += ((num_blks - 1) << BBSHIFT);
 556	}
 557
 558	for (i = (*last_blk) - 1; i >= 0; i--) {
 559		if (i < start_blk) {
 560			/* valid log record not found */
 561			xfs_warn(log->l_mp,
 562		"Log inconsistent (didn't find previous header)");
 563			ASSERT(0);
 564			error = -EIO;
 565			goto out;
 566		}
 567
 568		if (smallmem) {
 569			error = xlog_bread(log, i, 1, bp, &offset);
 570			if (error)
 571				goto out;
 572		}
 573
 574		head = (xlog_rec_header_t *)offset;
 575
 576		if (head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM))
 577			break;
 578
 579		if (!smallmem)
 580			offset -= BBSIZE;
 581	}
 582
 583	/*
 584	 * We hit the beginning of the physical log & still no header.  Return
 585	 * to caller.  If caller can handle a return of -1, then this routine
 586	 * will be called again for the end of the physical log.
 587	 */
 588	if (i == -1) {
 589		error = 1;
 590		goto out;
 591	}
 592
 593	/*
 594	 * We have the final block of the good log (the first block
 595	 * of the log record _before_ the head. So we check the uuid.
 596	 */
 597	if ((error = xlog_header_check_mount(log->l_mp, head)))
 598		goto out;
 599
 600	/*
 601	 * We may have found a log record header before we expected one.
 602	 * last_blk will be the 1st block # with a given cycle #.  We may end
 603	 * up reading an entire log record.  In this case, we don't want to
 604	 * reset last_blk.  Only when last_blk points in the middle of a log
 605	 * record do we update last_blk.
 606	 */
 607	if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
 608		uint	h_size = be32_to_cpu(head->h_size);
 609
 610		xhdrs = h_size / XLOG_HEADER_CYCLE_SIZE;
 611		if (h_size % XLOG_HEADER_CYCLE_SIZE)
 612			xhdrs++;
 613	} else {
 614		xhdrs = 1;
 615	}
 616
 617	if (*last_blk - i + extra_bblks !=
 618	    BTOBB(be32_to_cpu(head->h_len)) + xhdrs)
 619		*last_blk = i;
 620
 621out:
 622	xlog_put_bp(bp);
 623	return error;
 624}
 625
 626/*
 627 * Head is defined to be the point of the log where the next log write
 628 * could go.  This means that incomplete LR writes at the end are
 629 * eliminated when calculating the head.  We aren't guaranteed that previous
 630 * LR have complete transactions.  We only know that a cycle number of
 631 * current cycle number -1 won't be present in the log if we start writing
 632 * from our current block number.
 633 *
 634 * last_blk contains the block number of the first block with a given
 635 * cycle number.
 636 *
 637 * Return: zero if normal, non-zero if error.
 638 */
 639STATIC int
 640xlog_find_head(
 641	struct xlog	*log,
 642	xfs_daddr_t	*return_head_blk)
 643{
 644	xfs_buf_t	*bp;
 645	char		*offset;
 646	xfs_daddr_t	new_blk, first_blk, start_blk, last_blk, head_blk;
 647	int		num_scan_bblks;
 648	uint		first_half_cycle, last_half_cycle;
 649	uint		stop_on_cycle;
 650	int		error, log_bbnum = log->l_logBBsize;
 651
 652	/* Is the end of the log device zeroed? */
 653	error = xlog_find_zeroed(log, &first_blk);
 654	if (error < 0) {
 655		xfs_warn(log->l_mp, "empty log check failed");
 656		return error;
 657	}
 658	if (error == 1) {
 659		*return_head_blk = first_blk;
 660
 661		/* Is the whole lot zeroed? */
 662		if (!first_blk) {
 663			/* Linux XFS shouldn't generate totally zeroed logs -
 664			 * mkfs etc write a dummy unmount record to a fresh
 665			 * log so we can store the uuid in there
 666			 */
 667			xfs_warn(log->l_mp, "totally zeroed log");
 668		}
 669
 670		return 0;
 671	}
 672
 673	first_blk = 0;			/* get cycle # of 1st block */
 674	bp = xlog_get_bp(log, 1);
 675	if (!bp)
 676		return -ENOMEM;
 677
 678	error = xlog_bread(log, 0, 1, bp, &offset);
 679	if (error)
 680		goto bp_err;
 681
 682	first_half_cycle = xlog_get_cycle(offset);
 683
 684	last_blk = head_blk = log_bbnum - 1;	/* get cycle # of last block */
 685	error = xlog_bread(log, last_blk, 1, bp, &offset);
 686	if (error)
 687		goto bp_err;
 688
 689	last_half_cycle = xlog_get_cycle(offset);
 690	ASSERT(last_half_cycle != 0);
 691
 692	/*
 693	 * If the 1st half cycle number is equal to the last half cycle number,
 694	 * then the entire log is stamped with the same cycle number.  In this
 695	 * case, head_blk can't be set to zero (which makes sense).  The below
 696	 * math doesn't work out properly with head_blk equal to zero.  Instead,
 697	 * we set it to log_bbnum which is an invalid block number, but this
 698	 * value makes the math correct.  If head_blk doesn't changed through
 699	 * all the tests below, *head_blk is set to zero at the very end rather
 700	 * than log_bbnum.  In a sense, log_bbnum and zero are the same block
 701	 * in a circular file.
 702	 */
 703	if (first_half_cycle == last_half_cycle) {
 704		/*
 705		 * In this case we believe that the entire log should have
 706		 * cycle number last_half_cycle.  We need to scan backwards
 707		 * from the end verifying that there are no holes still
 708		 * containing last_half_cycle - 1.  If we find such a hole,
 709		 * then the start of that hole will be the new head.  The
 710		 * simple case looks like
 711		 *        x | x ... | x - 1 | x
 712		 * Another case that fits this picture would be
 713		 *        x | x + 1 | x ... | x
 714		 * In this case the head really is somewhere at the end of the
 715		 * log, as one of the latest writes at the beginning was
 716		 * incomplete.
 717		 * One more case is
 718		 *        x | x + 1 | x ... | x - 1 | x
 719		 * This is really the combination of the above two cases, and
 720		 * the head has to end up at the start of the x-1 hole at the
 721		 * end of the log.
 722		 *
 723		 * In the 256k log case, we will read from the beginning to the
 724		 * end of the log and search for cycle numbers equal to x-1.
 725		 * We don't worry about the x+1 blocks that we encounter,
 726		 * because we know that they cannot be the head since the log
 727		 * started with x.
 728		 */
 729		head_blk = log_bbnum;
 730		stop_on_cycle = last_half_cycle - 1;
 731	} else {
 732		/*
 733		 * In this case we want to find the first block with cycle
 734		 * number matching last_half_cycle.  We expect the log to be
 735		 * some variation on
 736		 *        x + 1 ... | x ... | x
 737		 * The first block with cycle number x (last_half_cycle) will
 738		 * be where the new head belongs.  First we do a binary search
 739		 * for the first occurrence of last_half_cycle.  The binary
 740		 * search may not be totally accurate, so then we scan back
 741		 * from there looking for occurrences of last_half_cycle before
 742		 * us.  If that backwards scan wraps around the beginning of
 743		 * the log, then we look for occurrences of last_half_cycle - 1
 744		 * at the end of the log.  The cases we're looking for look
 745		 * like
 746		 *                               v binary search stopped here
 747		 *        x + 1 ... | x | x + 1 | x ... | x
 748		 *                   ^ but we want to locate this spot
 749		 * or
 750		 *        <---------> less than scan distance
 751		 *        x + 1 ... | x ... | x - 1 | x
 752		 *                           ^ we want to locate this spot
 753		 */
 754		stop_on_cycle = last_half_cycle;
 755		if ((error = xlog_find_cycle_start(log, bp, first_blk,
 756						&head_blk, last_half_cycle)))
 757			goto bp_err;
 758	}
 759
 760	/*
 761	 * Now validate the answer.  Scan back some number of maximum possible
 762	 * blocks and make sure each one has the expected cycle number.  The
 763	 * maximum is determined by the total possible amount of buffering
 764	 * in the in-core log.  The following number can be made tighter if
 765	 * we actually look at the block size of the filesystem.
 766	 */
 767	num_scan_bblks = min_t(int, log_bbnum, XLOG_TOTAL_REC_SHIFT(log));
 768	if (head_blk >= num_scan_bblks) {
 769		/*
 770		 * We are guaranteed that the entire check can be performed
 771		 * in one buffer.
 772		 */
 773		start_blk = head_blk - num_scan_bblks;
 774		if ((error = xlog_find_verify_cycle(log,
 775						start_blk, num_scan_bblks,
 776						stop_on_cycle, &new_blk)))
 777			goto bp_err;
 778		if (new_blk != -1)
 779			head_blk = new_blk;
 780	} else {		/* need to read 2 parts of log */
 781		/*
 782		 * We are going to scan backwards in the log in two parts.
 783		 * First we scan the physical end of the log.  In this part
 784		 * of the log, we are looking for blocks with cycle number
 785		 * last_half_cycle - 1.
 786		 * If we find one, then we know that the log starts there, as
 787		 * we've found a hole that didn't get written in going around
 788		 * the end of the physical log.  The simple case for this is
 789		 *        x + 1 ... | x ... | x - 1 | x
 790		 *        <---------> less than scan distance
 791		 * If all of the blocks at the end of the log have cycle number
 792		 * last_half_cycle, then we check the blocks at the start of
 793		 * the log looking for occurrences of last_half_cycle.  If we
 794		 * find one, then our current estimate for the location of the
 795		 * first occurrence of last_half_cycle is wrong and we move
 796		 * back to the hole we've found.  This case looks like
 797		 *        x + 1 ... | x | x + 1 | x ...
 798		 *                               ^ binary search stopped here
 799		 * Another case we need to handle that only occurs in 256k
 800		 * logs is
 801		 *        x + 1 ... | x ... | x+1 | x ...
 802		 *                   ^ binary search stops here
 803		 * In a 256k log, the scan at the end of the log will see the
 804		 * x + 1 blocks.  We need to skip past those since that is
 805		 * certainly not the head of the log.  By searching for
 806		 * last_half_cycle-1 we accomplish that.
 807		 */
 808		ASSERT(head_blk <= INT_MAX &&
 809			(xfs_daddr_t) num_scan_bblks >= head_blk);
 810		start_blk = log_bbnum - (num_scan_bblks - head_blk);
 811		if ((error = xlog_find_verify_cycle(log, start_blk,
 812					num_scan_bblks - (int)head_blk,
 813					(stop_on_cycle - 1), &new_blk)))
 814			goto bp_err;
 815		if (new_blk != -1) {
 816			head_blk = new_blk;
 817			goto validate_head;
 818		}
 819
 820		/*
 821		 * Scan beginning of log now.  The last part of the physical
 822		 * log is good.  This scan needs to verify that it doesn't find
 823		 * the last_half_cycle.
 824		 */
 825		start_blk = 0;
 826		ASSERT(head_blk <= INT_MAX);
 827		if ((error = xlog_find_verify_cycle(log,
 828					start_blk, (int)head_blk,
 829					stop_on_cycle, &new_blk)))
 830			goto bp_err;
 831		if (new_blk != -1)
 832			head_blk = new_blk;
 833	}
 834
 835validate_head:
 836	/*
 837	 * Now we need to make sure head_blk is not pointing to a block in
 838	 * the middle of a log record.
 839	 */
 840	num_scan_bblks = XLOG_REC_SHIFT(log);
 841	if (head_blk >= num_scan_bblks) {
 842		start_blk = head_blk - num_scan_bblks; /* don't read head_blk */
 843
 844		/* start ptr at last block ptr before head_blk */
 845		error = xlog_find_verify_log_record(log, start_blk, &head_blk, 0);
 846		if (error == 1)
 847			error = -EIO;
 848		if (error)
 849			goto bp_err;
 850	} else {
 851		start_blk = 0;
 852		ASSERT(head_blk <= INT_MAX);
 853		error = xlog_find_verify_log_record(log, start_blk, &head_blk, 0);
 854		if (error < 0)
 855			goto bp_err;
 856		if (error == 1) {
 857			/* We hit the beginning of the log during our search */
 858			start_blk = log_bbnum - (num_scan_bblks - head_blk);
 859			new_blk = log_bbnum;
 860			ASSERT(start_blk <= INT_MAX &&
 861				(xfs_daddr_t) log_bbnum-start_blk >= 0);
 862			ASSERT(head_blk <= INT_MAX);
 863			error = xlog_find_verify_log_record(log, start_blk,
 864							&new_blk, (int)head_blk);
 865			if (error == 1)
 866				error = -EIO;
 867			if (error)
 868				goto bp_err;
 869			if (new_blk != log_bbnum)
 870				head_blk = new_blk;
 871		} else if (error)
 872			goto bp_err;
 873	}
 874
 875	xlog_put_bp(bp);
 876	if (head_blk == log_bbnum)
 877		*return_head_blk = 0;
 878	else
 879		*return_head_blk = head_blk;
 880	/*
 881	 * When returning here, we have a good block number.  Bad block
 882	 * means that during a previous crash, we didn't have a clean break
 883	 * from cycle number N to cycle number N-1.  In this case, we need
 884	 * to find the first block with cycle number N-1.
 885	 */
 886	return 0;
 887
 888 bp_err:
 889	xlog_put_bp(bp);
 890
 891	if (error)
 892		xfs_warn(log->l_mp, "failed to find log head");
 893	return error;
 894}
 895
 896/*
 897 * Seek backwards in the log for log record headers.
 898 *
 899 * Given a starting log block, walk backwards until we find the provided number
 900 * of records or hit the provided tail block. The return value is the number of
 901 * records encountered or a negative error code. The log block and buffer
 902 * pointer of the last record seen are returned in rblk and rhead respectively.
 903 */
 904STATIC int
 905xlog_rseek_logrec_hdr(
 906	struct xlog		*log,
 907	xfs_daddr_t		head_blk,
 908	xfs_daddr_t		tail_blk,
 909	int			count,
 910	struct xfs_buf		*bp,
 911	xfs_daddr_t		*rblk,
 912	struct xlog_rec_header	**rhead,
 913	bool			*wrapped)
 914{
 915	int			i;
 916	int			error;
 917	int			found = 0;
 918	char			*offset = NULL;
 919	xfs_daddr_t		end_blk;
 920
 921	*wrapped = false;
 922
 923	/*
 924	 * Walk backwards from the head block until we hit the tail or the first
 925	 * block in the log.
 926	 */
 927	end_blk = head_blk > tail_blk ? tail_blk : 0;
 928	for (i = (int) head_blk - 1; i >= end_blk; i--) {
 929		error = xlog_bread(log, i, 1, bp, &offset);
 930		if (error)
 931			goto out_error;
 932
 933		if (*(__be32 *) offset == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
 934			*rblk = i;
 935			*rhead = (struct xlog_rec_header *) offset;
 936			if (++found == count)
 937				break;
 938		}
 939	}
 940
 941	/*
 942	 * If we haven't hit the tail block or the log record header count,
 943	 * start looking again from the end of the physical log. Note that
 944	 * callers can pass head == tail if the tail is not yet known.
 945	 */
 946	if (tail_blk >= head_blk && found != count) {
 947		for (i = log->l_logBBsize - 1; i >= (int) tail_blk; i--) {
 948			error = xlog_bread(log, i, 1, bp, &offset);
 949			if (error)
 950				goto out_error;
 951
 952			if (*(__be32 *)offset ==
 953			    cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
 954				*wrapped = true;
 955				*rblk = i;
 956				*rhead = (struct xlog_rec_header *) offset;
 957				if (++found == count)
 958					break;
 959			}
 960		}
 961	}
 962
 963	return found;
 964
 965out_error:
 966	return error;
 967}
 968
 969/*
 970 * Seek forward in the log for log record headers.
 971 *
 972 * Given head and tail blocks, walk forward from the tail block until we find
 973 * the provided number of records or hit the head block. The return value is the
 974 * number of records encountered or a negative error code. The log block and
 975 * buffer pointer of the last record seen are returned in rblk and rhead
 976 * respectively.
 977 */
 978STATIC int
 979xlog_seek_logrec_hdr(
 980	struct xlog		*log,
 981	xfs_daddr_t		head_blk,
 982	xfs_daddr_t		tail_blk,
 983	int			count,
 984	struct xfs_buf		*bp,
 985	xfs_daddr_t		*rblk,
 986	struct xlog_rec_header	**rhead,
 987	bool			*wrapped)
 988{
 989	int			i;
 990	int			error;
 991	int			found = 0;
 992	char			*offset = NULL;
 993	xfs_daddr_t		end_blk;
 994
 995	*wrapped = false;
 996
 997	/*
 998	 * Walk forward from the tail block until we hit the head or the last
 999	 * block in the log.
1000	 */
1001	end_blk = head_blk > tail_blk ? head_blk : log->l_logBBsize - 1;
1002	for (i = (int) tail_blk; i <= end_blk; i++) {
1003		error = xlog_bread(log, i, 1, bp, &offset);
1004		if (error)
1005			goto out_error;
1006
1007		if (*(__be32 *) offset == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
1008			*rblk = i;
1009			*rhead = (struct xlog_rec_header *) offset;
1010			if (++found == count)
1011				break;
1012		}
1013	}
1014
1015	/*
1016	 * If we haven't hit the head block or the log record header count,
1017	 * start looking again from the start of the physical log.
1018	 */
1019	if (tail_blk > head_blk && found != count) {
1020		for (i = 0; i < (int) head_blk; i++) {
1021			error = xlog_bread(log, i, 1, bp, &offset);
1022			if (error)
1023				goto out_error;
1024
1025			if (*(__be32 *)offset ==
1026			    cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
1027				*wrapped = true;
1028				*rblk = i;
1029				*rhead = (struct xlog_rec_header *) offset;
1030				if (++found == count)
1031					break;
1032			}
1033		}
1034	}
1035
1036	return found;
1037
1038out_error:
1039	return error;
1040}
1041
1042/*
1043 * Calculate distance from head to tail (i.e., unused space in the log).
1044 */
1045static inline int
1046xlog_tail_distance(
1047	struct xlog	*log,
1048	xfs_daddr_t	head_blk,
1049	xfs_daddr_t	tail_blk)
1050{
1051	if (head_blk < tail_blk)
1052		return tail_blk - head_blk;
1053
1054	return tail_blk + (log->l_logBBsize - head_blk);
1055}
1056
1057/*
1058 * Verify the log tail. This is particularly important when torn or incomplete
1059 * writes have been detected near the front of the log and the head has been
1060 * walked back accordingly.
1061 *
1062 * We also have to handle the case where the tail was pinned and the head
1063 * blocked behind the tail right before a crash. If the tail had been pushed
1064 * immediately prior to the crash and the subsequent checkpoint was only
1065 * partially written, it's possible it overwrote the last referenced tail in the
1066 * log with garbage. This is not a coherency problem because the tail must have
1067 * been pushed before it can be overwritten, but appears as log corruption to
1068 * recovery because we have no way to know the tail was updated if the
1069 * subsequent checkpoint didn't write successfully.
1070 *
1071 * Therefore, CRC check the log from tail to head. If a failure occurs and the
1072 * offending record is within max iclog bufs from the head, walk the tail
1073 * forward and retry until a valid tail is found or corruption is detected out
1074 * of the range of a possible overwrite.
1075 */
1076STATIC int
1077xlog_verify_tail(
1078	struct xlog		*log,
1079	xfs_daddr_t		head_blk,
1080	xfs_daddr_t		*tail_blk,
1081	int			hsize)
1082{
1083	struct xlog_rec_header	*thead;
1084	struct xfs_buf		*bp;
1085	xfs_daddr_t		first_bad;
 
1086	int			error = 0;
1087	bool			wrapped;
1088	xfs_daddr_t		tmp_tail;
1089	xfs_daddr_t		orig_tail = *tail_blk;
1090
1091	bp = xlog_get_bp(log, 1);
1092	if (!bp)
1093		return -ENOMEM;
1094
1095	/*
1096	 * Make sure the tail points to a record (returns positive count on
1097	 * success).
1098	 */
1099	error = xlog_seek_logrec_hdr(log, head_blk, *tail_blk, 1, bp,
1100			&tmp_tail, &thead, &wrapped);
1101	if (error < 0)
 
 
 
1102		goto out;
1103	if (*tail_blk != tmp_tail)
1104		*tail_blk = tmp_tail;
1105
1106	/*
1107	 * Run a CRC check from the tail to the head. We can't just check
1108	 * MAX_ICLOGS records past the tail because the tail may point to stale
1109	 * blocks cleared during the search for the head/tail. These blocks are
1110	 * overwritten with zero-length records and thus record count is not a
1111	 * reliable indicator of the iclog state before a crash.
1112	 */
1113	first_bad = 0;
1114	error = xlog_do_recovery_pass(log, head_blk, *tail_blk,
1115				      XLOG_RECOVER_CRCPASS, &first_bad);
1116	while ((error == -EFSBADCRC || error == -EFSCORRUPTED) && first_bad) {
1117		int	tail_distance;
1118
1119		/*
1120		 * Is corruption within range of the head? If so, retry from
1121		 * the next record. Otherwise return an error.
1122		 */
1123		tail_distance = xlog_tail_distance(log, head_blk, first_bad);
1124		if (tail_distance > BTOBB(XLOG_MAX_ICLOGS * hsize))
1125			break;
1126
1127		/* skip to the next record; returns positive count on success */
1128		error = xlog_seek_logrec_hdr(log, head_blk, first_bad, 2, bp,
1129				&tmp_tail, &thead, &wrapped);
1130		if (error < 0)
1131			goto out;
1132
1133		*tail_blk = tmp_tail;
1134		first_bad = 0;
1135		error = xlog_do_recovery_pass(log, head_blk, *tail_blk,
1136					      XLOG_RECOVER_CRCPASS, &first_bad);
1137	}
1138
1139	if (!error && *tail_blk != orig_tail)
1140		xfs_warn(log->l_mp,
1141		"Tail block (0x%llx) overwrite detected. Updated to 0x%llx",
1142			 orig_tail, *tail_blk);
1143out:
1144	xlog_put_bp(bp);
1145	return error;
1146}
1147
1148/*
1149 * Detect and trim torn writes from the head of the log.
1150 *
1151 * Storage without sector atomicity guarantees can result in torn writes in the
1152 * log in the event of a crash. Our only means to detect this scenario is via
1153 * CRC verification. While we can't always be certain that CRC verification
1154 * failure is due to a torn write vs. an unrelated corruption, we do know that
1155 * only a certain number (XLOG_MAX_ICLOGS) of log records can be written out at
1156 * one time. Therefore, CRC verify up to XLOG_MAX_ICLOGS records at the head of
1157 * the log and treat failures in this range as torn writes as a matter of
1158 * policy. In the event of CRC failure, the head is walked back to the last good
1159 * record in the log and the tail is updated from that record and verified.
1160 */
1161STATIC int
1162xlog_verify_head(
1163	struct xlog		*log,
1164	xfs_daddr_t		*head_blk,	/* in/out: unverified head */
1165	xfs_daddr_t		*tail_blk,	/* out: tail block */
1166	struct xfs_buf		*bp,
1167	xfs_daddr_t		*rhead_blk,	/* start blk of last record */
1168	struct xlog_rec_header	**rhead,	/* ptr to last record */
1169	bool			*wrapped)	/* last rec. wraps phys. log */
1170{
1171	struct xlog_rec_header	*tmp_rhead;
1172	struct xfs_buf		*tmp_bp;
1173	xfs_daddr_t		first_bad;
1174	xfs_daddr_t		tmp_rhead_blk;
1175	int			found;
1176	int			error;
1177	bool			tmp_wrapped;
1178
1179	/*
1180	 * Check the head of the log for torn writes. Search backwards from the
1181	 * head until we hit the tail or the maximum number of log record I/Os
1182	 * that could have been in flight at one time. Use a temporary buffer so
1183	 * we don't trash the rhead/bp pointers from the caller.
1184	 */
1185	tmp_bp = xlog_get_bp(log, 1);
1186	if (!tmp_bp)
1187		return -ENOMEM;
1188	error = xlog_rseek_logrec_hdr(log, *head_blk, *tail_blk,
1189				      XLOG_MAX_ICLOGS, tmp_bp, &tmp_rhead_blk,
1190				      &tmp_rhead, &tmp_wrapped);
1191	xlog_put_bp(tmp_bp);
1192	if (error < 0)
1193		return error;
1194
1195	/*
1196	 * Now run a CRC verification pass over the records starting at the
1197	 * block found above to the current head. If a CRC failure occurs, the
1198	 * log block of the first bad record is saved in first_bad.
1199	 */
1200	error = xlog_do_recovery_pass(log, *head_blk, tmp_rhead_blk,
1201				      XLOG_RECOVER_CRCPASS, &first_bad);
1202	if ((error == -EFSBADCRC || error == -EFSCORRUPTED) && first_bad) {
1203		/*
1204		 * We've hit a potential torn write. Reset the error and warn
1205		 * about it.
1206		 */
1207		error = 0;
1208		xfs_warn(log->l_mp,
1209"Torn write (CRC failure) detected at log block 0x%llx. Truncating head block from 0x%llx.",
1210			 first_bad, *head_blk);
1211
1212		/*
1213		 * Get the header block and buffer pointer for the last good
1214		 * record before the bad record.
1215		 *
1216		 * Note that xlog_find_tail() clears the blocks at the new head
1217		 * (i.e., the records with invalid CRC) if the cycle number
1218		 * matches the the current cycle.
1219		 */
1220		found = xlog_rseek_logrec_hdr(log, first_bad, *tail_blk, 1, bp,
1221					      rhead_blk, rhead, wrapped);
1222		if (found < 0)
1223			return found;
1224		if (found == 0)		/* XXX: right thing to do here? */
1225			return -EIO;
1226
1227		/*
1228		 * Reset the head block to the starting block of the first bad
1229		 * log record and set the tail block based on the last good
1230		 * record.
1231		 *
1232		 * Bail out if the updated head/tail match as this indicates
1233		 * possible corruption outside of the acceptable
1234		 * (XLOG_MAX_ICLOGS) range. This is a job for xfs_repair...
1235		 */
1236		*head_blk = first_bad;
1237		*tail_blk = BLOCK_LSN(be64_to_cpu((*rhead)->h_tail_lsn));
1238		if (*head_blk == *tail_blk) {
1239			ASSERT(0);
1240			return 0;
1241		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1242	}
1243	if (error)
1244		return error;
1245
1246	return xlog_verify_tail(log, *head_blk, tail_blk,
1247				be32_to_cpu((*rhead)->h_size));
1248}
1249
1250/*
1251 * Check whether the head of the log points to an unmount record. In other
1252 * words, determine whether the log is clean. If so, update the in-core state
1253 * appropriately.
1254 */
1255static int
1256xlog_check_unmount_rec(
1257	struct xlog		*log,
1258	xfs_daddr_t		*head_blk,
1259	xfs_daddr_t		*tail_blk,
1260	struct xlog_rec_header	*rhead,
1261	xfs_daddr_t		rhead_blk,
1262	struct xfs_buf		*bp,
1263	bool			*clean)
1264{
1265	struct xlog_op_header	*op_head;
1266	xfs_daddr_t		umount_data_blk;
1267	xfs_daddr_t		after_umount_blk;
1268	int			hblks;
1269	int			error;
1270	char			*offset;
1271
1272	*clean = false;
1273
1274	/*
1275	 * Look for unmount record. If we find it, then we know there was a
1276	 * clean unmount. Since 'i' could be the last block in the physical
1277	 * log, we convert to a log block before comparing to the head_blk.
1278	 *
1279	 * Save the current tail lsn to use to pass to xlog_clear_stale_blocks()
1280	 * below. We won't want to clear the unmount record if there is one, so
1281	 * we pass the lsn of the unmount record rather than the block after it.
1282	 */
1283	if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
1284		int	h_size = be32_to_cpu(rhead->h_size);
1285		int	h_version = be32_to_cpu(rhead->h_version);
1286
1287		if ((h_version & XLOG_VERSION_2) &&
1288		    (h_size > XLOG_HEADER_CYCLE_SIZE)) {
1289			hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
1290			if (h_size % XLOG_HEADER_CYCLE_SIZE)
1291				hblks++;
1292		} else {
1293			hblks = 1;
1294		}
1295	} else {
1296		hblks = 1;
1297	}
1298	after_umount_blk = rhead_blk + hblks + BTOBB(be32_to_cpu(rhead->h_len));
1299	after_umount_blk = do_mod(after_umount_blk, log->l_logBBsize);
1300	if (*head_blk == after_umount_blk &&
1301	    be32_to_cpu(rhead->h_num_logops) == 1) {
1302		umount_data_blk = rhead_blk + hblks;
1303		umount_data_blk = do_mod(umount_data_blk, log->l_logBBsize);
1304		error = xlog_bread(log, umount_data_blk, 1, bp, &offset);
1305		if (error)
1306			return error;
1307
1308		op_head = (struct xlog_op_header *)offset;
1309		if (op_head->oh_flags & XLOG_UNMOUNT_TRANS) {
1310			/*
1311			 * Set tail and last sync so that newly written log
1312			 * records will point recovery to after the current
1313			 * unmount record.
1314			 */
1315			xlog_assign_atomic_lsn(&log->l_tail_lsn,
1316					log->l_curr_cycle, after_umount_blk);
1317			xlog_assign_atomic_lsn(&log->l_last_sync_lsn,
1318					log->l_curr_cycle, after_umount_blk);
1319			*tail_blk = after_umount_blk;
1320
1321			*clean = true;
1322		}
1323	}
1324
1325	return 0;
1326}
1327
1328static void
1329xlog_set_state(
1330	struct xlog		*log,
1331	xfs_daddr_t		head_blk,
1332	struct xlog_rec_header	*rhead,
1333	xfs_daddr_t		rhead_blk,
1334	bool			bump_cycle)
1335{
1336	/*
1337	 * Reset log values according to the state of the log when we
1338	 * crashed.  In the case where head_blk == 0, we bump curr_cycle
1339	 * one because the next write starts a new cycle rather than
1340	 * continuing the cycle of the last good log record.  At this
1341	 * point we have guaranteed that all partial log records have been
1342	 * accounted for.  Therefore, we know that the last good log record
1343	 * written was complete and ended exactly on the end boundary
1344	 * of the physical log.
1345	 */
1346	log->l_prev_block = rhead_blk;
1347	log->l_curr_block = (int)head_blk;
1348	log->l_curr_cycle = be32_to_cpu(rhead->h_cycle);
1349	if (bump_cycle)
1350		log->l_curr_cycle++;
1351	atomic64_set(&log->l_tail_lsn, be64_to_cpu(rhead->h_tail_lsn));
1352	atomic64_set(&log->l_last_sync_lsn, be64_to_cpu(rhead->h_lsn));
1353	xlog_assign_grant_head(&log->l_reserve_head.grant, log->l_curr_cycle,
1354					BBTOB(log->l_curr_block));
1355	xlog_assign_grant_head(&log->l_write_head.grant, log->l_curr_cycle,
1356					BBTOB(log->l_curr_block));
1357}
1358
1359/*
1360 * Find the sync block number or the tail of the log.
1361 *
1362 * This will be the block number of the last record to have its
1363 * associated buffers synced to disk.  Every log record header has
1364 * a sync lsn embedded in it.  LSNs hold block numbers, so it is easy
1365 * to get a sync block number.  The only concern is to figure out which
1366 * log record header to believe.
1367 *
1368 * The following algorithm uses the log record header with the largest
1369 * lsn.  The entire log record does not need to be valid.  We only care
1370 * that the header is valid.
1371 *
1372 * We could speed up search by using current head_blk buffer, but it is not
1373 * available.
1374 */
1375STATIC int
1376xlog_find_tail(
1377	struct xlog		*log,
1378	xfs_daddr_t		*head_blk,
1379	xfs_daddr_t		*tail_blk)
1380{
1381	xlog_rec_header_t	*rhead;
1382	char			*offset = NULL;
1383	xfs_buf_t		*bp;
1384	int			error;
1385	xfs_daddr_t		rhead_blk;
1386	xfs_lsn_t		tail_lsn;
1387	bool			wrapped = false;
1388	bool			clean = false;
1389
1390	/*
1391	 * Find previous log record
1392	 */
1393	if ((error = xlog_find_head(log, head_blk)))
1394		return error;
1395	ASSERT(*head_blk < INT_MAX);
1396
1397	bp = xlog_get_bp(log, 1);
1398	if (!bp)
1399		return -ENOMEM;
1400	if (*head_blk == 0) {				/* special case */
1401		error = xlog_bread(log, 0, 1, bp, &offset);
1402		if (error)
1403			goto done;
1404
1405		if (xlog_get_cycle(offset) == 0) {
1406			*tail_blk = 0;
1407			/* leave all other log inited values alone */
1408			goto done;
1409		}
1410	}
1411
1412	/*
1413	 * Search backwards through the log looking for the log record header
1414	 * block. This wraps all the way back around to the head so something is
1415	 * seriously wrong if we can't find it.
1416	 */
1417	error = xlog_rseek_logrec_hdr(log, *head_blk, *head_blk, 1, bp,
1418				      &rhead_blk, &rhead, &wrapped);
1419	if (error < 0)
1420		return error;
1421	if (!error) {
1422		xfs_warn(log->l_mp, "%s: couldn't find sync record", __func__);
1423		return -EIO;
1424	}
1425	*tail_blk = BLOCK_LSN(be64_to_cpu(rhead->h_tail_lsn));
1426
1427	/*
1428	 * Set the log state based on the current head record.
1429	 */
1430	xlog_set_state(log, *head_blk, rhead, rhead_blk, wrapped);
1431	tail_lsn = atomic64_read(&log->l_tail_lsn);
1432
1433	/*
1434	 * Look for an unmount record at the head of the log. This sets the log
1435	 * state to determine whether recovery is necessary.
1436	 */
1437	error = xlog_check_unmount_rec(log, head_blk, tail_blk, rhead,
1438				       rhead_blk, bp, &clean);
1439	if (error)
1440		goto done;
1441
1442	/*
1443	 * Verify the log head if the log is not clean (e.g., we have anything
1444	 * but an unmount record at the head). This uses CRC verification to
1445	 * detect and trim torn writes. If discovered, CRC failures are
1446	 * considered torn writes and the log head is trimmed accordingly.
1447	 *
1448	 * Note that we can only run CRC verification when the log is dirty
1449	 * because there's no guarantee that the log data behind an unmount
1450	 * record is compatible with the current architecture.
1451	 */
1452	if (!clean) {
1453		xfs_daddr_t	orig_head = *head_blk;
1454
1455		error = xlog_verify_head(log, head_blk, tail_blk, bp,
1456					 &rhead_blk, &rhead, &wrapped);
1457		if (error)
1458			goto done;
1459
1460		/* update in-core state again if the head changed */
1461		if (*head_blk != orig_head) {
1462			xlog_set_state(log, *head_blk, rhead, rhead_blk,
1463				       wrapped);
1464			tail_lsn = atomic64_read(&log->l_tail_lsn);
1465			error = xlog_check_unmount_rec(log, head_blk, tail_blk,
1466						       rhead, rhead_blk, bp,
1467						       &clean);
1468			if (error)
1469				goto done;
1470		}
1471	}
1472
1473	/*
1474	 * Note that the unmount was clean. If the unmount was not clean, we
1475	 * need to know this to rebuild the superblock counters from the perag
1476	 * headers if we have a filesystem using non-persistent counters.
1477	 */
1478	if (clean)
1479		log->l_mp->m_flags |= XFS_MOUNT_WAS_CLEAN;
1480
1481	/*
1482	 * Make sure that there are no blocks in front of the head
1483	 * with the same cycle number as the head.  This can happen
1484	 * because we allow multiple outstanding log writes concurrently,
1485	 * and the later writes might make it out before earlier ones.
1486	 *
1487	 * We use the lsn from before modifying it so that we'll never
1488	 * overwrite the unmount record after a clean unmount.
1489	 *
1490	 * Do this only if we are going to recover the filesystem
1491	 *
1492	 * NOTE: This used to say "if (!readonly)"
1493	 * However on Linux, we can & do recover a read-only filesystem.
1494	 * We only skip recovery if NORECOVERY is specified on mount,
1495	 * in which case we would not be here.
1496	 *
1497	 * But... if the -device- itself is readonly, just skip this.
1498	 * We can't recover this device anyway, so it won't matter.
1499	 */
1500	if (!xfs_readonly_buftarg(log->l_mp->m_logdev_targp))
1501		error = xlog_clear_stale_blocks(log, tail_lsn);
1502
1503done:
1504	xlog_put_bp(bp);
1505
1506	if (error)
1507		xfs_warn(log->l_mp, "failed to locate log tail");
1508	return error;
1509}
1510
1511/*
1512 * Is the log zeroed at all?
1513 *
1514 * The last binary search should be changed to perform an X block read
1515 * once X becomes small enough.  You can then search linearly through
1516 * the X blocks.  This will cut down on the number of reads we need to do.
1517 *
1518 * If the log is partially zeroed, this routine will pass back the blkno
1519 * of the first block with cycle number 0.  It won't have a complete LR
1520 * preceding it.
1521 *
1522 * Return:
1523 *	0  => the log is completely written to
1524 *	1 => use *blk_no as the first block of the log
1525 *	<0 => error has occurred
1526 */
1527STATIC int
1528xlog_find_zeroed(
1529	struct xlog	*log,
1530	xfs_daddr_t	*blk_no)
1531{
1532	xfs_buf_t	*bp;
1533	char		*offset;
1534	uint	        first_cycle, last_cycle;
1535	xfs_daddr_t	new_blk, last_blk, start_blk;
1536	xfs_daddr_t     num_scan_bblks;
1537	int	        error, log_bbnum = log->l_logBBsize;
1538
1539	*blk_no = 0;
1540
1541	/* check totally zeroed log */
1542	bp = xlog_get_bp(log, 1);
1543	if (!bp)
1544		return -ENOMEM;
1545	error = xlog_bread(log, 0, 1, bp, &offset);
1546	if (error)
1547		goto bp_err;
1548
1549	first_cycle = xlog_get_cycle(offset);
1550	if (first_cycle == 0) {		/* completely zeroed log */
1551		*blk_no = 0;
1552		xlog_put_bp(bp);
1553		return 1;
1554	}
1555
1556	/* check partially zeroed log */
1557	error = xlog_bread(log, log_bbnum-1, 1, bp, &offset);
1558	if (error)
1559		goto bp_err;
1560
1561	last_cycle = xlog_get_cycle(offset);
1562	if (last_cycle != 0) {		/* log completely written to */
1563		xlog_put_bp(bp);
1564		return 0;
1565	} else if (first_cycle != 1) {
1566		/*
1567		 * If the cycle of the last block is zero, the cycle of
1568		 * the first block must be 1. If it's not, maybe we're
1569		 * not looking at a log... Bail out.
1570		 */
1571		xfs_warn(log->l_mp,
1572			"Log inconsistent or not a log (last==0, first!=1)");
1573		error = -EINVAL;
1574		goto bp_err;
1575	}
1576
1577	/* we have a partially zeroed log */
1578	last_blk = log_bbnum-1;
1579	if ((error = xlog_find_cycle_start(log, bp, 0, &last_blk, 0)))
1580		goto bp_err;
1581
1582	/*
1583	 * Validate the answer.  Because there is no way to guarantee that
1584	 * the entire log is made up of log records which are the same size,
1585	 * we scan over the defined maximum blocks.  At this point, the maximum
1586	 * is not chosen to mean anything special.   XXXmiken
1587	 */
1588	num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log);
1589	ASSERT(num_scan_bblks <= INT_MAX);
1590
1591	if (last_blk < num_scan_bblks)
1592		num_scan_bblks = last_blk;
1593	start_blk = last_blk - num_scan_bblks;
1594
1595	/*
1596	 * We search for any instances of cycle number 0 that occur before
1597	 * our current estimate of the head.  What we're trying to detect is
1598	 *        1 ... | 0 | 1 | 0...
1599	 *                       ^ binary search ends here
1600	 */
1601	if ((error = xlog_find_verify_cycle(log, start_blk,
1602					 (int)num_scan_bblks, 0, &new_blk)))
1603		goto bp_err;
1604	if (new_blk != -1)
1605		last_blk = new_blk;
1606
1607	/*
1608	 * Potentially backup over partial log record write.  We don't need
1609	 * to search the end of the log because we know it is zero.
1610	 */
1611	error = xlog_find_verify_log_record(log, start_blk, &last_blk, 0);
1612	if (error == 1)
1613		error = -EIO;
1614	if (error)
1615		goto bp_err;
1616
1617	*blk_no = last_blk;
1618bp_err:
1619	xlog_put_bp(bp);
1620	if (error)
1621		return error;
1622	return 1;
1623}
1624
1625/*
1626 * These are simple subroutines used by xlog_clear_stale_blocks() below
1627 * to initialize a buffer full of empty log record headers and write
1628 * them into the log.
1629 */
1630STATIC void
1631xlog_add_record(
1632	struct xlog		*log,
1633	char			*buf,
1634	int			cycle,
1635	int			block,
1636	int			tail_cycle,
1637	int			tail_block)
1638{
1639	xlog_rec_header_t	*recp = (xlog_rec_header_t *)buf;
1640
1641	memset(buf, 0, BBSIZE);
1642	recp->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM);
1643	recp->h_cycle = cpu_to_be32(cycle);
1644	recp->h_version = cpu_to_be32(
1645			xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? 2 : 1);
1646	recp->h_lsn = cpu_to_be64(xlog_assign_lsn(cycle, block));
1647	recp->h_tail_lsn = cpu_to_be64(xlog_assign_lsn(tail_cycle, tail_block));
1648	recp->h_fmt = cpu_to_be32(XLOG_FMT);
1649	memcpy(&recp->h_fs_uuid, &log->l_mp->m_sb.sb_uuid, sizeof(uuid_t));
1650}
1651
1652STATIC int
1653xlog_write_log_records(
1654	struct xlog	*log,
1655	int		cycle,
1656	int		start_block,
1657	int		blocks,
1658	int		tail_cycle,
1659	int		tail_block)
1660{
1661	char		*offset;
1662	xfs_buf_t	*bp;
1663	int		balign, ealign;
1664	int		sectbb = log->l_sectBBsize;
1665	int		end_block = start_block + blocks;
1666	int		bufblks;
1667	int		error = 0;
1668	int		i, j = 0;
1669
1670	/*
1671	 * Greedily allocate a buffer big enough to handle the full
1672	 * range of basic blocks to be written.  If that fails, try
1673	 * a smaller size.  We need to be able to write at least a
1674	 * log sector, or we're out of luck.
1675	 */
1676	bufblks = 1 << ffs(blocks);
1677	while (bufblks > log->l_logBBsize)
1678		bufblks >>= 1;
1679	while (!(bp = xlog_get_bp(log, bufblks))) {
1680		bufblks >>= 1;
1681		if (bufblks < sectbb)
1682			return -ENOMEM;
1683	}
1684
1685	/* We may need to do a read at the start to fill in part of
1686	 * the buffer in the starting sector not covered by the first
1687	 * write below.
1688	 */
1689	balign = round_down(start_block, sectbb);
1690	if (balign != start_block) {
1691		error = xlog_bread_noalign(log, start_block, 1, bp);
1692		if (error)
1693			goto out_put_bp;
1694
1695		j = start_block - balign;
1696	}
1697
1698	for (i = start_block; i < end_block; i += bufblks) {
1699		int		bcount, endcount;
1700
1701		bcount = min(bufblks, end_block - start_block);
1702		endcount = bcount - j;
1703
1704		/* We may need to do a read at the end to fill in part of
1705		 * the buffer in the final sector not covered by the write.
1706		 * If this is the same sector as the above read, skip it.
1707		 */
1708		ealign = round_down(end_block, sectbb);
1709		if (j == 0 && (start_block + endcount > ealign)) {
1710			offset = bp->b_addr + BBTOB(ealign - start_block);
1711			error = xlog_bread_offset(log, ealign, sectbb,
1712							bp, offset);
1713			if (error)
1714				break;
1715
1716		}
1717
1718		offset = xlog_align(log, start_block, endcount, bp);
1719		for (; j < endcount; j++) {
1720			xlog_add_record(log, offset, cycle, i+j,
1721					tail_cycle, tail_block);
1722			offset += BBSIZE;
1723		}
1724		error = xlog_bwrite(log, start_block, endcount, bp);
1725		if (error)
1726			break;
1727		start_block += endcount;
1728		j = 0;
1729	}
1730
1731 out_put_bp:
1732	xlog_put_bp(bp);
1733	return error;
1734}
1735
1736/*
1737 * This routine is called to blow away any incomplete log writes out
1738 * in front of the log head.  We do this so that we won't become confused
1739 * if we come up, write only a little bit more, and then crash again.
1740 * If we leave the partial log records out there, this situation could
1741 * cause us to think those partial writes are valid blocks since they
1742 * have the current cycle number.  We get rid of them by overwriting them
1743 * with empty log records with the old cycle number rather than the
1744 * current one.
1745 *
1746 * The tail lsn is passed in rather than taken from
1747 * the log so that we will not write over the unmount record after a
1748 * clean unmount in a 512 block log.  Doing so would leave the log without
1749 * any valid log records in it until a new one was written.  If we crashed
1750 * during that time we would not be able to recover.
1751 */
1752STATIC int
1753xlog_clear_stale_blocks(
1754	struct xlog	*log,
1755	xfs_lsn_t	tail_lsn)
1756{
1757	int		tail_cycle, head_cycle;
1758	int		tail_block, head_block;
1759	int		tail_distance, max_distance;
1760	int		distance;
1761	int		error;
1762
1763	tail_cycle = CYCLE_LSN(tail_lsn);
1764	tail_block = BLOCK_LSN(tail_lsn);
1765	head_cycle = log->l_curr_cycle;
1766	head_block = log->l_curr_block;
1767
1768	/*
1769	 * Figure out the distance between the new head of the log
1770	 * and the tail.  We want to write over any blocks beyond the
1771	 * head that we may have written just before the crash, but
1772	 * we don't want to overwrite the tail of the log.
1773	 */
1774	if (head_cycle == tail_cycle) {
1775		/*
1776		 * The tail is behind the head in the physical log,
1777		 * so the distance from the head to the tail is the
1778		 * distance from the head to the end of the log plus
1779		 * the distance from the beginning of the log to the
1780		 * tail.
1781		 */
1782		if (unlikely(head_block < tail_block || head_block >= log->l_logBBsize)) {
1783			XFS_ERROR_REPORT("xlog_clear_stale_blocks(1)",
1784					 XFS_ERRLEVEL_LOW, log->l_mp);
1785			return -EFSCORRUPTED;
1786		}
1787		tail_distance = tail_block + (log->l_logBBsize - head_block);
1788	} else {
1789		/*
1790		 * The head is behind the tail in the physical log,
1791		 * so the distance from the head to the tail is just
1792		 * the tail block minus the head block.
1793		 */
1794		if (unlikely(head_block >= tail_block || head_cycle != (tail_cycle + 1))){
1795			XFS_ERROR_REPORT("xlog_clear_stale_blocks(2)",
1796					 XFS_ERRLEVEL_LOW, log->l_mp);
1797			return -EFSCORRUPTED;
1798		}
1799		tail_distance = tail_block - head_block;
1800	}
1801
1802	/*
1803	 * If the head is right up against the tail, we can't clear
1804	 * anything.
1805	 */
1806	if (tail_distance <= 0) {
1807		ASSERT(tail_distance == 0);
1808		return 0;
1809	}
1810
1811	max_distance = XLOG_TOTAL_REC_SHIFT(log);
1812	/*
1813	 * Take the smaller of the maximum amount of outstanding I/O
1814	 * we could have and the distance to the tail to clear out.
1815	 * We take the smaller so that we don't overwrite the tail and
1816	 * we don't waste all day writing from the head to the tail
1817	 * for no reason.
1818	 */
1819	max_distance = MIN(max_distance, tail_distance);
1820
1821	if ((head_block + max_distance) <= log->l_logBBsize) {
1822		/*
1823		 * We can stomp all the blocks we need to without
1824		 * wrapping around the end of the log.  Just do it
1825		 * in a single write.  Use the cycle number of the
1826		 * current cycle minus one so that the log will look like:
1827		 *     n ... | n - 1 ...
1828		 */
1829		error = xlog_write_log_records(log, (head_cycle - 1),
1830				head_block, max_distance, tail_cycle,
1831				tail_block);
1832		if (error)
1833			return error;
1834	} else {
1835		/*
1836		 * We need to wrap around the end of the physical log in
1837		 * order to clear all the blocks.  Do it in two separate
1838		 * I/Os.  The first write should be from the head to the
1839		 * end of the physical log, and it should use the current
1840		 * cycle number minus one just like above.
1841		 */
1842		distance = log->l_logBBsize - head_block;
1843		error = xlog_write_log_records(log, (head_cycle - 1),
1844				head_block, distance, tail_cycle,
1845				tail_block);
1846
1847		if (error)
1848			return error;
1849
1850		/*
1851		 * Now write the blocks at the start of the physical log.
1852		 * This writes the remainder of the blocks we want to clear.
1853		 * It uses the current cycle number since we're now on the
1854		 * same cycle as the head so that we get:
1855		 *    n ... n ... | n - 1 ...
1856		 *    ^^^^^ blocks we're writing
1857		 */
1858		distance = max_distance - (log->l_logBBsize - head_block);
1859		error = xlog_write_log_records(log, head_cycle, 0, distance,
1860				tail_cycle, tail_block);
1861		if (error)
1862			return error;
1863	}
1864
1865	return 0;
1866}
1867
1868/******************************************************************************
1869 *
1870 *		Log recover routines
1871 *
1872 ******************************************************************************
1873 */
1874
1875/*
1876 * Sort the log items in the transaction.
1877 *
1878 * The ordering constraints are defined by the inode allocation and unlink
1879 * behaviour. The rules are:
1880 *
1881 *	1. Every item is only logged once in a given transaction. Hence it
1882 *	   represents the last logged state of the item. Hence ordering is
1883 *	   dependent on the order in which operations need to be performed so
1884 *	   required initial conditions are always met.
1885 *
1886 *	2. Cancelled buffers are recorded in pass 1 in a separate table and
1887 *	   there's nothing to replay from them so we can simply cull them
1888 *	   from the transaction. However, we can't do that until after we've
1889 *	   replayed all the other items because they may be dependent on the
1890 *	   cancelled buffer and replaying the cancelled buffer can remove it
1891 *	   form the cancelled buffer table. Hence they have tobe done last.
1892 *
1893 *	3. Inode allocation buffers must be replayed before inode items that
1894 *	   read the buffer and replay changes into it. For filesystems using the
1895 *	   ICREATE transactions, this means XFS_LI_ICREATE objects need to get
1896 *	   treated the same as inode allocation buffers as they create and
1897 *	   initialise the buffers directly.
1898 *
1899 *	4. Inode unlink buffers must be replayed after inode items are replayed.
1900 *	   This ensures that inodes are completely flushed to the inode buffer
1901 *	   in a "free" state before we remove the unlinked inode list pointer.
1902 *
1903 * Hence the ordering needs to be inode allocation buffers first, inode items
1904 * second, inode unlink buffers third and cancelled buffers last.
1905 *
1906 * But there's a problem with that - we can't tell an inode allocation buffer
1907 * apart from a regular buffer, so we can't separate them. We can, however,
1908 * tell an inode unlink buffer from the others, and so we can separate them out
1909 * from all the other buffers and move them to last.
1910 *
1911 * Hence, 4 lists, in order from head to tail:
1912 *	- buffer_list for all buffers except cancelled/inode unlink buffers
1913 *	- item_list for all non-buffer items
1914 *	- inode_buffer_list for inode unlink buffers
1915 *	- cancel_list for the cancelled buffers
1916 *
1917 * Note that we add objects to the tail of the lists so that first-to-last
1918 * ordering is preserved within the lists. Adding objects to the head of the
1919 * list means when we traverse from the head we walk them in last-to-first
1920 * order. For cancelled buffers and inode unlink buffers this doesn't matter,
1921 * but for all other items there may be specific ordering that we need to
1922 * preserve.
1923 */
1924STATIC int
1925xlog_recover_reorder_trans(
1926	struct xlog		*log,
1927	struct xlog_recover	*trans,
1928	int			pass)
1929{
1930	xlog_recover_item_t	*item, *n;
1931	int			error = 0;
1932	LIST_HEAD(sort_list);
1933	LIST_HEAD(cancel_list);
1934	LIST_HEAD(buffer_list);
1935	LIST_HEAD(inode_buffer_list);
1936	LIST_HEAD(inode_list);
1937
1938	list_splice_init(&trans->r_itemq, &sort_list);
1939	list_for_each_entry_safe(item, n, &sort_list, ri_list) {
1940		xfs_buf_log_format_t	*buf_f = item->ri_buf[0].i_addr;
1941
1942		switch (ITEM_TYPE(item)) {
1943		case XFS_LI_ICREATE:
1944			list_move_tail(&item->ri_list, &buffer_list);
1945			break;
1946		case XFS_LI_BUF:
1947			if (buf_f->blf_flags & XFS_BLF_CANCEL) {
1948				trace_xfs_log_recover_item_reorder_head(log,
1949							trans, item, pass);
1950				list_move(&item->ri_list, &cancel_list);
1951				break;
1952			}
1953			if (buf_f->blf_flags & XFS_BLF_INODE_BUF) {
1954				list_move(&item->ri_list, &inode_buffer_list);
1955				break;
1956			}
1957			list_move_tail(&item->ri_list, &buffer_list);
1958			break;
1959		case XFS_LI_INODE:
1960		case XFS_LI_DQUOT:
1961		case XFS_LI_QUOTAOFF:
1962		case XFS_LI_EFD:
1963		case XFS_LI_EFI:
1964		case XFS_LI_RUI:
1965		case XFS_LI_RUD:
1966		case XFS_LI_CUI:
1967		case XFS_LI_CUD:
1968		case XFS_LI_BUI:
1969		case XFS_LI_BUD:
1970			trace_xfs_log_recover_item_reorder_tail(log,
1971							trans, item, pass);
1972			list_move_tail(&item->ri_list, &inode_list);
1973			break;
1974		default:
1975			xfs_warn(log->l_mp,
1976				"%s: unrecognized type of log operation",
1977				__func__);
1978			ASSERT(0);
1979			/*
1980			 * return the remaining items back to the transaction
1981			 * item list so they can be freed in caller.
1982			 */
1983			if (!list_empty(&sort_list))
1984				list_splice_init(&sort_list, &trans->r_itemq);
1985			error = -EIO;
1986			goto out;
1987		}
1988	}
1989out:
1990	ASSERT(list_empty(&sort_list));
1991	if (!list_empty(&buffer_list))
1992		list_splice(&buffer_list, &trans->r_itemq);
1993	if (!list_empty(&inode_list))
1994		list_splice_tail(&inode_list, &trans->r_itemq);
1995	if (!list_empty(&inode_buffer_list))
1996		list_splice_tail(&inode_buffer_list, &trans->r_itemq);
1997	if (!list_empty(&cancel_list))
1998		list_splice_tail(&cancel_list, &trans->r_itemq);
1999	return error;
2000}
2001
2002/*
2003 * Build up the table of buf cancel records so that we don't replay
2004 * cancelled data in the second pass.  For buffer records that are
2005 * not cancel records, there is nothing to do here so we just return.
2006 *
2007 * If we get a cancel record which is already in the table, this indicates
2008 * that the buffer was cancelled multiple times.  In order to ensure
2009 * that during pass 2 we keep the record in the table until we reach its
2010 * last occurrence in the log, we keep a reference count in the cancel
2011 * record in the table to tell us how many times we expect to see this
2012 * record during the second pass.
2013 */
2014STATIC int
2015xlog_recover_buffer_pass1(
2016	struct xlog			*log,
2017	struct xlog_recover_item	*item)
2018{
2019	xfs_buf_log_format_t	*buf_f = item->ri_buf[0].i_addr;
2020	struct list_head	*bucket;
2021	struct xfs_buf_cancel	*bcp;
2022
2023	/*
2024	 * If this isn't a cancel buffer item, then just return.
2025	 */
2026	if (!(buf_f->blf_flags & XFS_BLF_CANCEL)) {
2027		trace_xfs_log_recover_buf_not_cancel(log, buf_f);
2028		return 0;
2029	}
2030
2031	/*
2032	 * Insert an xfs_buf_cancel record into the hash table of them.
2033	 * If there is already an identical record, bump its reference count.
2034	 */
2035	bucket = XLOG_BUF_CANCEL_BUCKET(log, buf_f->blf_blkno);
2036	list_for_each_entry(bcp, bucket, bc_list) {
2037		if (bcp->bc_blkno == buf_f->blf_blkno &&
2038		    bcp->bc_len == buf_f->blf_len) {
2039			bcp->bc_refcount++;
2040			trace_xfs_log_recover_buf_cancel_ref_inc(log, buf_f);
2041			return 0;
2042		}
2043	}
2044
2045	bcp = kmem_alloc(sizeof(struct xfs_buf_cancel), KM_SLEEP);
2046	bcp->bc_blkno = buf_f->blf_blkno;
2047	bcp->bc_len = buf_f->blf_len;
2048	bcp->bc_refcount = 1;
2049	list_add_tail(&bcp->bc_list, bucket);
2050
2051	trace_xfs_log_recover_buf_cancel_add(log, buf_f);
2052	return 0;
2053}
2054
2055/*
2056 * Check to see whether the buffer being recovered has a corresponding
2057 * entry in the buffer cancel record table. If it is, return the cancel
2058 * buffer structure to the caller.
2059 */
2060STATIC struct xfs_buf_cancel *
2061xlog_peek_buffer_cancelled(
2062	struct xlog		*log,
2063	xfs_daddr_t		blkno,
2064	uint			len,
2065	unsigned short			flags)
2066{
2067	struct list_head	*bucket;
2068	struct xfs_buf_cancel	*bcp;
2069
2070	if (!log->l_buf_cancel_table) {
2071		/* empty table means no cancelled buffers in the log */
2072		ASSERT(!(flags & XFS_BLF_CANCEL));
2073		return NULL;
2074	}
2075
2076	bucket = XLOG_BUF_CANCEL_BUCKET(log, blkno);
2077	list_for_each_entry(bcp, bucket, bc_list) {
2078		if (bcp->bc_blkno == blkno && bcp->bc_len == len)
2079			return bcp;
2080	}
2081
2082	/*
2083	 * We didn't find a corresponding entry in the table, so return 0 so
2084	 * that the buffer is NOT cancelled.
2085	 */
2086	ASSERT(!(flags & XFS_BLF_CANCEL));
2087	return NULL;
2088}
2089
2090/*
2091 * If the buffer is being cancelled then return 1 so that it will be cancelled,
2092 * otherwise return 0.  If the buffer is actually a buffer cancel item
2093 * (XFS_BLF_CANCEL is set), then decrement the refcount on the entry in the
2094 * table and remove it from the table if this is the last reference.
2095 *
2096 * We remove the cancel record from the table when we encounter its last
2097 * occurrence in the log so that if the same buffer is re-used again after its
2098 * last cancellation we actually replay the changes made at that point.
2099 */
2100STATIC int
2101xlog_check_buffer_cancelled(
2102	struct xlog		*log,
2103	xfs_daddr_t		blkno,
2104	uint			len,
2105	unsigned short			flags)
2106{
2107	struct xfs_buf_cancel	*bcp;
2108
2109	bcp = xlog_peek_buffer_cancelled(log, blkno, len, flags);
2110	if (!bcp)
2111		return 0;
2112
2113	/*
2114	 * We've go a match, so return 1 so that the recovery of this buffer
2115	 * is cancelled.  If this buffer is actually a buffer cancel log
2116	 * item, then decrement the refcount on the one in the table and
2117	 * remove it if this is the last reference.
2118	 */
2119	if (flags & XFS_BLF_CANCEL) {
2120		if (--bcp->bc_refcount == 0) {
2121			list_del(&bcp->bc_list);
2122			kmem_free(bcp);
2123		}
2124	}
2125	return 1;
2126}
2127
2128/*
2129 * Perform recovery for a buffer full of inodes.  In these buffers, the only
2130 * data which should be recovered is that which corresponds to the
2131 * di_next_unlinked pointers in the on disk inode structures.  The rest of the
2132 * data for the inodes is always logged through the inodes themselves rather
2133 * than the inode buffer and is recovered in xlog_recover_inode_pass2().
2134 *
2135 * The only time when buffers full of inodes are fully recovered is when the
2136 * buffer is full of newly allocated inodes.  In this case the buffer will
2137 * not be marked as an inode buffer and so will be sent to
2138 * xlog_recover_do_reg_buffer() below during recovery.
2139 */
2140STATIC int
2141xlog_recover_do_inode_buffer(
2142	struct xfs_mount	*mp,
2143	xlog_recover_item_t	*item,
2144	struct xfs_buf		*bp,
2145	xfs_buf_log_format_t	*buf_f)
2146{
2147	int			i;
2148	int			item_index = 0;
2149	int			bit = 0;
2150	int			nbits = 0;
2151	int			reg_buf_offset = 0;
2152	int			reg_buf_bytes = 0;
2153	int			next_unlinked_offset;
2154	int			inodes_per_buf;
2155	xfs_agino_t		*logged_nextp;
2156	xfs_agino_t		*buffer_nextp;
2157
2158	trace_xfs_log_recover_buf_inode_buf(mp->m_log, buf_f);
2159
2160	/*
2161	 * Post recovery validation only works properly on CRC enabled
2162	 * filesystems.
2163	 */
2164	if (xfs_sb_version_hascrc(&mp->m_sb))
2165		bp->b_ops = &xfs_inode_buf_ops;
2166
2167	inodes_per_buf = BBTOB(bp->b_io_length) >> mp->m_sb.sb_inodelog;
2168	for (i = 0; i < inodes_per_buf; i++) {
2169		next_unlinked_offset = (i * mp->m_sb.sb_inodesize) +
2170			offsetof(xfs_dinode_t, di_next_unlinked);
2171
2172		while (next_unlinked_offset >=
2173		       (reg_buf_offset + reg_buf_bytes)) {
2174			/*
2175			 * The next di_next_unlinked field is beyond
2176			 * the current logged region.  Find the next
2177			 * logged region that contains or is beyond
2178			 * the current di_next_unlinked field.
2179			 */
2180			bit += nbits;
2181			bit = xfs_next_bit(buf_f->blf_data_map,
2182					   buf_f->blf_map_size, bit);
2183
2184			/*
2185			 * If there are no more logged regions in the
2186			 * buffer, then we're done.
2187			 */
2188			if (bit == -1)
2189				return 0;
2190
2191			nbits = xfs_contig_bits(buf_f->blf_data_map,
2192						buf_f->blf_map_size, bit);
2193			ASSERT(nbits > 0);
2194			reg_buf_offset = bit << XFS_BLF_SHIFT;
2195			reg_buf_bytes = nbits << XFS_BLF_SHIFT;
2196			item_index++;
2197		}
2198
2199		/*
2200		 * If the current logged region starts after the current
2201		 * di_next_unlinked field, then move on to the next
2202		 * di_next_unlinked field.
2203		 */
2204		if (next_unlinked_offset < reg_buf_offset)
2205			continue;
2206
2207		ASSERT(item->ri_buf[item_index].i_addr != NULL);
2208		ASSERT((item->ri_buf[item_index].i_len % XFS_BLF_CHUNK) == 0);
2209		ASSERT((reg_buf_offset + reg_buf_bytes) <=
2210							BBTOB(bp->b_io_length));
2211
2212		/*
2213		 * The current logged region contains a copy of the
2214		 * current di_next_unlinked field.  Extract its value
2215		 * and copy it to the buffer copy.
2216		 */
2217		logged_nextp = item->ri_buf[item_index].i_addr +
2218				next_unlinked_offset - reg_buf_offset;
2219		if (unlikely(*logged_nextp == 0)) {
2220			xfs_alert(mp,
2221		"Bad inode buffer log record (ptr = "PTR_FMT", bp = "PTR_FMT"). "
2222		"Trying to replay bad (0) inode di_next_unlinked field.",
2223				item, bp);
2224			XFS_ERROR_REPORT("xlog_recover_do_inode_buf",
2225					 XFS_ERRLEVEL_LOW, mp);
2226			return -EFSCORRUPTED;
2227		}
2228
2229		buffer_nextp = xfs_buf_offset(bp, next_unlinked_offset);
2230		*buffer_nextp = *logged_nextp;
2231
2232		/*
2233		 * If necessary, recalculate the CRC in the on-disk inode. We
2234		 * have to leave the inode in a consistent state for whoever
2235		 * reads it next....
2236		 */
2237		xfs_dinode_calc_crc(mp,
2238				xfs_buf_offset(bp, i * mp->m_sb.sb_inodesize));
2239
2240	}
2241
2242	return 0;
2243}
2244
2245/*
2246 * V5 filesystems know the age of the buffer on disk being recovered. We can
2247 * have newer objects on disk than we are replaying, and so for these cases we
2248 * don't want to replay the current change as that will make the buffer contents
2249 * temporarily invalid on disk.
2250 *
2251 * The magic number might not match the buffer type we are going to recover
2252 * (e.g. reallocated blocks), so we ignore the xfs_buf_log_format flags.  Hence
2253 * extract the LSN of the existing object in the buffer based on it's current
2254 * magic number.  If we don't recognise the magic number in the buffer, then
2255 * return a LSN of -1 so that the caller knows it was an unrecognised block and
2256 * so can recover the buffer.
2257 *
2258 * Note: we cannot rely solely on magic number matches to determine that the
2259 * buffer has a valid LSN - we also need to verify that it belongs to this
2260 * filesystem, so we need to extract the object's LSN and compare it to that
2261 * which we read from the superblock. If the UUIDs don't match, then we've got a
2262 * stale metadata block from an old filesystem instance that we need to recover
2263 * over the top of.
2264 */
2265static xfs_lsn_t
2266xlog_recover_get_buf_lsn(
2267	struct xfs_mount	*mp,
2268	struct xfs_buf		*bp)
2269{
2270	uint32_t		magic32;
2271	uint16_t		magic16;
2272	uint16_t		magicda;
2273	void			*blk = bp->b_addr;
2274	uuid_t			*uuid;
2275	xfs_lsn_t		lsn = -1;
2276
2277	/* v4 filesystems always recover immediately */
2278	if (!xfs_sb_version_hascrc(&mp->m_sb))
2279		goto recover_immediately;
2280
2281	magic32 = be32_to_cpu(*(__be32 *)blk);
2282	switch (magic32) {
2283	case XFS_ABTB_CRC_MAGIC:
2284	case XFS_ABTC_CRC_MAGIC:
2285	case XFS_ABTB_MAGIC:
2286	case XFS_ABTC_MAGIC:
2287	case XFS_RMAP_CRC_MAGIC:
2288	case XFS_REFC_CRC_MAGIC:
2289	case XFS_IBT_CRC_MAGIC:
2290	case XFS_IBT_MAGIC: {
2291		struct xfs_btree_block *btb = blk;
2292
2293		lsn = be64_to_cpu(btb->bb_u.s.bb_lsn);
2294		uuid = &btb->bb_u.s.bb_uuid;
2295		break;
2296	}
2297	case XFS_BMAP_CRC_MAGIC:
2298	case XFS_BMAP_MAGIC: {
2299		struct xfs_btree_block *btb = blk;
2300
2301		lsn = be64_to_cpu(btb->bb_u.l.bb_lsn);
2302		uuid = &btb->bb_u.l.bb_uuid;
2303		break;
2304	}
2305	case XFS_AGF_MAGIC:
2306		lsn = be64_to_cpu(((struct xfs_agf *)blk)->agf_lsn);
2307		uuid = &((struct xfs_agf *)blk)->agf_uuid;
2308		break;
2309	case XFS_AGFL_MAGIC:
2310		lsn = be64_to_cpu(((struct xfs_agfl *)blk)->agfl_lsn);
2311		uuid = &((struct xfs_agfl *)blk)->agfl_uuid;
2312		break;
2313	case XFS_AGI_MAGIC:
2314		lsn = be64_to_cpu(((struct xfs_agi *)blk)->agi_lsn);
2315		uuid = &((struct xfs_agi *)blk)->agi_uuid;
2316		break;
2317	case XFS_SYMLINK_MAGIC:
2318		lsn = be64_to_cpu(((struct xfs_dsymlink_hdr *)blk)->sl_lsn);
2319		uuid = &((struct xfs_dsymlink_hdr *)blk)->sl_uuid;
2320		break;
2321	case XFS_DIR3_BLOCK_MAGIC:
2322	case XFS_DIR3_DATA_MAGIC:
2323	case XFS_DIR3_FREE_MAGIC:
2324		lsn = be64_to_cpu(((struct xfs_dir3_blk_hdr *)blk)->lsn);
2325		uuid = &((struct xfs_dir3_blk_hdr *)blk)->uuid;
2326		break;
2327	case XFS_ATTR3_RMT_MAGIC:
2328		/*
2329		 * Remote attr blocks are written synchronously, rather than
2330		 * being logged. That means they do not contain a valid LSN
2331		 * (i.e. transactionally ordered) in them, and hence any time we
2332		 * see a buffer to replay over the top of a remote attribute
2333		 * block we should simply do so.
2334		 */
2335		goto recover_immediately;
2336	case XFS_SB_MAGIC:
2337		/*
2338		 * superblock uuids are magic. We may or may not have a
2339		 * sb_meta_uuid on disk, but it will be set in the in-core
2340		 * superblock. We set the uuid pointer for verification
2341		 * according to the superblock feature mask to ensure we check
2342		 * the relevant UUID in the superblock.
2343		 */
2344		lsn = be64_to_cpu(((struct xfs_dsb *)blk)->sb_lsn);
2345		if (xfs_sb_version_hasmetauuid(&mp->m_sb))
2346			uuid = &((struct xfs_dsb *)blk)->sb_meta_uuid;
2347		else
2348			uuid = &((struct xfs_dsb *)blk)->sb_uuid;
2349		break;
2350	default:
2351		break;
2352	}
2353
2354	if (lsn != (xfs_lsn_t)-1) {
2355		if (!uuid_equal(&mp->m_sb.sb_meta_uuid, uuid))
2356			goto recover_immediately;
2357		return lsn;
2358	}
2359
2360	magicda = be16_to_cpu(((struct xfs_da_blkinfo *)blk)->magic);
2361	switch (magicda) {
2362	case XFS_DIR3_LEAF1_MAGIC:
2363	case XFS_DIR3_LEAFN_MAGIC:
2364	case XFS_DA3_NODE_MAGIC:
2365		lsn = be64_to_cpu(((struct xfs_da3_blkinfo *)blk)->lsn);
2366		uuid = &((struct xfs_da3_blkinfo *)blk)->uuid;
2367		break;
2368	default:
2369		break;
2370	}
2371
2372	if (lsn != (xfs_lsn_t)-1) {
2373		if (!uuid_equal(&mp->m_sb.sb_uuid, uuid))
2374			goto recover_immediately;
2375		return lsn;
2376	}
2377
2378	/*
2379	 * We do individual object checks on dquot and inode buffers as they
2380	 * have their own individual LSN records. Also, we could have a stale
2381	 * buffer here, so we have to at least recognise these buffer types.
2382	 *
2383	 * A notd complexity here is inode unlinked list processing - it logs
2384	 * the inode directly in the buffer, but we don't know which inodes have
2385	 * been modified, and there is no global buffer LSN. Hence we need to
2386	 * recover all inode buffer types immediately. This problem will be
2387	 * fixed by logical logging of the unlinked list modifications.
2388	 */
2389	magic16 = be16_to_cpu(*(__be16 *)blk);
2390	switch (magic16) {
2391	case XFS_DQUOT_MAGIC:
2392	case XFS_DINODE_MAGIC:
2393		goto recover_immediately;
2394	default:
2395		break;
2396	}
2397
2398	/* unknown buffer contents, recover immediately */
2399
2400recover_immediately:
2401	return (xfs_lsn_t)-1;
2402
2403}
2404
2405/*
2406 * Validate the recovered buffer is of the correct type and attach the
2407 * appropriate buffer operations to them for writeback. Magic numbers are in a
2408 * few places:
2409 *	the first 16 bits of the buffer (inode buffer, dquot buffer),
2410 *	the first 32 bits of the buffer (most blocks),
2411 *	inside a struct xfs_da_blkinfo at the start of the buffer.
2412 */
2413static void
2414xlog_recover_validate_buf_type(
2415	struct xfs_mount	*mp,
2416	struct xfs_buf		*bp,
2417	xfs_buf_log_format_t	*buf_f,
2418	xfs_lsn_t		current_lsn)
2419{
2420	struct xfs_da_blkinfo	*info = bp->b_addr;
2421	uint32_t		magic32;
2422	uint16_t		magic16;
2423	uint16_t		magicda;
2424	char			*warnmsg = NULL;
2425
2426	/*
2427	 * We can only do post recovery validation on items on CRC enabled
2428	 * fielsystems as we need to know when the buffer was written to be able
2429	 * to determine if we should have replayed the item. If we replay old
2430	 * metadata over a newer buffer, then it will enter a temporarily
2431	 * inconsistent state resulting in verification failures. Hence for now
2432	 * just avoid the verification stage for non-crc filesystems
2433	 */
2434	if (!xfs_sb_version_hascrc(&mp->m_sb))
2435		return;
2436
2437	magic32 = be32_to_cpu(*(__be32 *)bp->b_addr);
2438	magic16 = be16_to_cpu(*(__be16*)bp->b_addr);
2439	magicda = be16_to_cpu(info->magic);
2440	switch (xfs_blft_from_flags(buf_f)) {
2441	case XFS_BLFT_BTREE_BUF:
2442		switch (magic32) {
2443		case XFS_ABTB_CRC_MAGIC:
2444		case XFS_ABTC_CRC_MAGIC:
2445		case XFS_ABTB_MAGIC:
2446		case XFS_ABTC_MAGIC:
2447			bp->b_ops = &xfs_allocbt_buf_ops;
2448			break;
2449		case XFS_IBT_CRC_MAGIC:
2450		case XFS_FIBT_CRC_MAGIC:
2451		case XFS_IBT_MAGIC:
2452		case XFS_FIBT_MAGIC:
2453			bp->b_ops = &xfs_inobt_buf_ops;
2454			break;
2455		case XFS_BMAP_CRC_MAGIC:
2456		case XFS_BMAP_MAGIC:
2457			bp->b_ops = &xfs_bmbt_buf_ops;
2458			break;
2459		case XFS_RMAP_CRC_MAGIC:
2460			bp->b_ops = &xfs_rmapbt_buf_ops;
2461			break;
2462		case XFS_REFC_CRC_MAGIC:
2463			bp->b_ops = &xfs_refcountbt_buf_ops;
2464			break;
2465		default:
2466			warnmsg = "Bad btree block magic!";
2467			break;
2468		}
2469		break;
2470	case XFS_BLFT_AGF_BUF:
2471		if (magic32 != XFS_AGF_MAGIC) {
2472			warnmsg = "Bad AGF block magic!";
2473			break;
2474		}
2475		bp->b_ops = &xfs_agf_buf_ops;
2476		break;
2477	case XFS_BLFT_AGFL_BUF:
2478		if (magic32 != XFS_AGFL_MAGIC) {
2479			warnmsg = "Bad AGFL block magic!";
2480			break;
2481		}
2482		bp->b_ops = &xfs_agfl_buf_ops;
2483		break;
2484	case XFS_BLFT_AGI_BUF:
2485		if (magic32 != XFS_AGI_MAGIC) {
2486			warnmsg = "Bad AGI block magic!";
2487			break;
2488		}
2489		bp->b_ops = &xfs_agi_buf_ops;
2490		break;
2491	case XFS_BLFT_UDQUOT_BUF:
2492	case XFS_BLFT_PDQUOT_BUF:
2493	case XFS_BLFT_GDQUOT_BUF:
2494#ifdef CONFIG_XFS_QUOTA
2495		if (magic16 != XFS_DQUOT_MAGIC) {
2496			warnmsg = "Bad DQUOT block magic!";
2497			break;
2498		}
2499		bp->b_ops = &xfs_dquot_buf_ops;
2500#else
2501		xfs_alert(mp,
2502	"Trying to recover dquots without QUOTA support built in!");
2503		ASSERT(0);
2504#endif
2505		break;
2506	case XFS_BLFT_DINO_BUF:
2507		if (magic16 != XFS_DINODE_MAGIC) {
2508			warnmsg = "Bad INODE block magic!";
2509			break;
2510		}
2511		bp->b_ops = &xfs_inode_buf_ops;
2512		break;
2513	case XFS_BLFT_SYMLINK_BUF:
2514		if (magic32 != XFS_SYMLINK_MAGIC) {
2515			warnmsg = "Bad symlink block magic!";
2516			break;
2517		}
2518		bp->b_ops = &xfs_symlink_buf_ops;
2519		break;
2520	case XFS_BLFT_DIR_BLOCK_BUF:
2521		if (magic32 != XFS_DIR2_BLOCK_MAGIC &&
2522		    magic32 != XFS_DIR3_BLOCK_MAGIC) {
2523			warnmsg = "Bad dir block magic!";
2524			break;
2525		}
2526		bp->b_ops = &xfs_dir3_block_buf_ops;
2527		break;
2528	case XFS_BLFT_DIR_DATA_BUF:
2529		if (magic32 != XFS_DIR2_DATA_MAGIC &&
2530		    magic32 != XFS_DIR3_DATA_MAGIC) {
2531			warnmsg = "Bad dir data magic!";
2532			break;
2533		}
2534		bp->b_ops = &xfs_dir3_data_buf_ops;
2535		break;
2536	case XFS_BLFT_DIR_FREE_BUF:
2537		if (magic32 != XFS_DIR2_FREE_MAGIC &&
2538		    magic32 != XFS_DIR3_FREE_MAGIC) {
2539			warnmsg = "Bad dir3 free magic!";
2540			break;
2541		}
2542		bp->b_ops = &xfs_dir3_free_buf_ops;
2543		break;
2544	case XFS_BLFT_DIR_LEAF1_BUF:
2545		if (magicda != XFS_DIR2_LEAF1_MAGIC &&
2546		    magicda != XFS_DIR3_LEAF1_MAGIC) {
2547			warnmsg = "Bad dir leaf1 magic!";
2548			break;
2549		}
2550		bp->b_ops = &xfs_dir3_leaf1_buf_ops;
2551		break;
2552	case XFS_BLFT_DIR_LEAFN_BUF:
2553		if (magicda != XFS_DIR2_LEAFN_MAGIC &&
2554		    magicda != XFS_DIR3_LEAFN_MAGIC) {
2555			warnmsg = "Bad dir leafn magic!";
2556			break;
2557		}
2558		bp->b_ops = &xfs_dir3_leafn_buf_ops;
2559		break;
2560	case XFS_BLFT_DA_NODE_BUF:
2561		if (magicda != XFS_DA_NODE_MAGIC &&
2562		    magicda != XFS_DA3_NODE_MAGIC) {
2563			warnmsg = "Bad da node magic!";
2564			break;
2565		}
2566		bp->b_ops = &xfs_da3_node_buf_ops;
2567		break;
2568	case XFS_BLFT_ATTR_LEAF_BUF:
2569		if (magicda != XFS_ATTR_LEAF_MAGIC &&
2570		    magicda != XFS_ATTR3_LEAF_MAGIC) {
2571			warnmsg = "Bad attr leaf magic!";
2572			break;
2573		}
2574		bp->b_ops = &xfs_attr3_leaf_buf_ops;
2575		break;
2576	case XFS_BLFT_ATTR_RMT_BUF:
2577		if (magic32 != XFS_ATTR3_RMT_MAGIC) {
2578			warnmsg = "Bad attr remote magic!";
2579			break;
2580		}
2581		bp->b_ops = &xfs_attr3_rmt_buf_ops;
2582		break;
2583	case XFS_BLFT_SB_BUF:
2584		if (magic32 != XFS_SB_MAGIC) {
2585			warnmsg = "Bad SB block magic!";
2586			break;
2587		}
2588		bp->b_ops = &xfs_sb_buf_ops;
2589		break;
2590#ifdef CONFIG_XFS_RT
2591	case XFS_BLFT_RTBITMAP_BUF:
2592	case XFS_BLFT_RTSUMMARY_BUF:
2593		/* no magic numbers for verification of RT buffers */
2594		bp->b_ops = &xfs_rtbuf_ops;
2595		break;
2596#endif /* CONFIG_XFS_RT */
2597	default:
2598		xfs_warn(mp, "Unknown buffer type %d!",
2599			 xfs_blft_from_flags(buf_f));
2600		break;
2601	}
2602
2603	/*
2604	 * Nothing else to do in the case of a NULL current LSN as this means
2605	 * the buffer is more recent than the change in the log and will be
2606	 * skipped.
2607	 */
2608	if (current_lsn == NULLCOMMITLSN)
2609		return;
2610
2611	if (warnmsg) {
2612		xfs_warn(mp, warnmsg);
2613		ASSERT(0);
2614	}
2615
2616	/*
2617	 * We must update the metadata LSN of the buffer as it is written out to
2618	 * ensure that older transactions never replay over this one and corrupt
2619	 * the buffer. This can occur if log recovery is interrupted at some
2620	 * point after the current transaction completes, at which point a
2621	 * subsequent mount starts recovery from the beginning.
2622	 *
2623	 * Write verifiers update the metadata LSN from log items attached to
2624	 * the buffer. Therefore, initialize a bli purely to carry the LSN to
2625	 * the verifier. We'll clean it up in our ->iodone() callback.
2626	 */
2627	if (bp->b_ops) {
2628		struct xfs_buf_log_item	*bip;
2629
2630		ASSERT(!bp->b_iodone || bp->b_iodone == xlog_recover_iodone);
2631		bp->b_iodone = xlog_recover_iodone;
2632		xfs_buf_item_init(bp, mp);
2633		bip = bp->b_log_item;
2634		bip->bli_item.li_lsn = current_lsn;
2635	}
2636}
2637
2638/*
2639 * Perform a 'normal' buffer recovery.  Each logged region of the
2640 * buffer should be copied over the corresponding region in the
2641 * given buffer.  The bitmap in the buf log format structure indicates
2642 * where to place the logged data.
2643 */
2644STATIC void
2645xlog_recover_do_reg_buffer(
2646	struct xfs_mount	*mp,
2647	xlog_recover_item_t	*item,
2648	struct xfs_buf		*bp,
2649	xfs_buf_log_format_t	*buf_f,
2650	xfs_lsn_t		current_lsn)
2651{
2652	int			i;
2653	int			bit;
2654	int			nbits;
2655	xfs_failaddr_t		fa;
2656
2657	trace_xfs_log_recover_buf_reg_buf(mp->m_log, buf_f);
2658
2659	bit = 0;
2660	i = 1;  /* 0 is the buf format structure */
2661	while (1) {
2662		bit = xfs_next_bit(buf_f->blf_data_map,
2663				   buf_f->blf_map_size, bit);
2664		if (bit == -1)
2665			break;
2666		nbits = xfs_contig_bits(buf_f->blf_data_map,
2667					buf_f->blf_map_size, bit);
2668		ASSERT(nbits > 0);
2669		ASSERT(item->ri_buf[i].i_addr != NULL);
2670		ASSERT(item->ri_buf[i].i_len % XFS_BLF_CHUNK == 0);
2671		ASSERT(BBTOB(bp->b_io_length) >=
2672		       ((uint)bit << XFS_BLF_SHIFT) + (nbits << XFS_BLF_SHIFT));
2673
2674		/*
2675		 * The dirty regions logged in the buffer, even though
2676		 * contiguous, may span multiple chunks. This is because the
2677		 * dirty region may span a physical page boundary in a buffer
2678		 * and hence be split into two separate vectors for writing into
2679		 * the log. Hence we need to trim nbits back to the length of
2680		 * the current region being copied out of the log.
2681		 */
2682		if (item->ri_buf[i].i_len < (nbits << XFS_BLF_SHIFT))
2683			nbits = item->ri_buf[i].i_len >> XFS_BLF_SHIFT;
2684
2685		/*
2686		 * Do a sanity check if this is a dquot buffer. Just checking
2687		 * the first dquot in the buffer should do. XXXThis is
2688		 * probably a good thing to do for other buf types also.
2689		 */
2690		fa = NULL;
2691		if (buf_f->blf_flags &
2692		   (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) {
2693			if (item->ri_buf[i].i_addr == NULL) {
2694				xfs_alert(mp,
2695					"XFS: NULL dquot in %s.", __func__);
2696				goto next;
2697			}
2698			if (item->ri_buf[i].i_len < sizeof(xfs_disk_dquot_t)) {
2699				xfs_alert(mp,
2700					"XFS: dquot too small (%d) in %s.",
2701					item->ri_buf[i].i_len, __func__);
2702				goto next;
2703			}
2704			fa = xfs_dquot_verify(mp, item->ri_buf[i].i_addr,
2705					       -1, 0, 0);
2706			if (fa) {
2707				xfs_alert(mp,
2708	"dquot corrupt at %pS trying to replay into block 0x%llx",
2709					fa, bp->b_bn);
2710				goto next;
2711			}
2712		}
2713
2714		memcpy(xfs_buf_offset(bp,
2715			(uint)bit << XFS_BLF_SHIFT),	/* dest */
2716			item->ri_buf[i].i_addr,		/* source */
2717			nbits<<XFS_BLF_SHIFT);		/* length */
2718 next:
2719		i++;
2720		bit += nbits;
2721	}
2722
2723	/* Shouldn't be any more regions */
2724	ASSERT(i == item->ri_total);
2725
2726	xlog_recover_validate_buf_type(mp, bp, buf_f, current_lsn);
2727}
2728
2729/*
2730 * Perform a dquot buffer recovery.
2731 * Simple algorithm: if we have found a QUOTAOFF log item of the same type
2732 * (ie. USR or GRP), then just toss this buffer away; don't recover it.
2733 * Else, treat it as a regular buffer and do recovery.
2734 *
2735 * Return false if the buffer was tossed and true if we recovered the buffer to
2736 * indicate to the caller if the buffer needs writing.
2737 */
2738STATIC bool
2739xlog_recover_do_dquot_buffer(
2740	struct xfs_mount		*mp,
2741	struct xlog			*log,
2742	struct xlog_recover_item	*item,
2743	struct xfs_buf			*bp,
2744	struct xfs_buf_log_format	*buf_f)
2745{
2746	uint			type;
2747
2748	trace_xfs_log_recover_buf_dquot_buf(log, buf_f);
2749
2750	/*
2751	 * Filesystems are required to send in quota flags at mount time.
2752	 */
2753	if (!mp->m_qflags)
2754		return false;
2755
2756	type = 0;
2757	if (buf_f->blf_flags & XFS_BLF_UDQUOT_BUF)
2758		type |= XFS_DQ_USER;
2759	if (buf_f->blf_flags & XFS_BLF_PDQUOT_BUF)
2760		type |= XFS_DQ_PROJ;
2761	if (buf_f->blf_flags & XFS_BLF_GDQUOT_BUF)
2762		type |= XFS_DQ_GROUP;
2763	/*
2764	 * This type of quotas was turned off, so ignore this buffer
2765	 */
2766	if (log->l_quotaoffs_flag & type)
2767		return false;
2768
2769	xlog_recover_do_reg_buffer(mp, item, bp, buf_f, NULLCOMMITLSN);
2770	return true;
2771}
2772
2773/*
2774 * This routine replays a modification made to a buffer at runtime.
2775 * There are actually two types of buffer, regular and inode, which
2776 * are handled differently.  Inode buffers are handled differently
2777 * in that we only recover a specific set of data from them, namely
2778 * the inode di_next_unlinked fields.  This is because all other inode
2779 * data is actually logged via inode records and any data we replay
2780 * here which overlaps that may be stale.
2781 *
2782 * When meta-data buffers are freed at run time we log a buffer item
2783 * with the XFS_BLF_CANCEL bit set to indicate that previous copies
2784 * of the buffer in the log should not be replayed at recovery time.
2785 * This is so that if the blocks covered by the buffer are reused for
2786 * file data before we crash we don't end up replaying old, freed
2787 * meta-data into a user's file.
2788 *
2789 * To handle the cancellation of buffer log items, we make two passes
2790 * over the log during recovery.  During the first we build a table of
2791 * those buffers which have been cancelled, and during the second we
2792 * only replay those buffers which do not have corresponding cancel
2793 * records in the table.  See xlog_recover_buffer_pass[1,2] above
2794 * for more details on the implementation of the table of cancel records.
2795 */
2796STATIC int
2797xlog_recover_buffer_pass2(
2798	struct xlog			*log,
2799	struct list_head		*buffer_list,
2800	struct xlog_recover_item	*item,
2801	xfs_lsn_t			current_lsn)
2802{
2803	xfs_buf_log_format_t	*buf_f = item->ri_buf[0].i_addr;
2804	xfs_mount_t		*mp = log->l_mp;
2805	xfs_buf_t		*bp;
2806	int			error;
2807	uint			buf_flags;
2808	xfs_lsn_t		lsn;
2809
2810	/*
2811	 * In this pass we only want to recover all the buffers which have
2812	 * not been cancelled and are not cancellation buffers themselves.
2813	 */
2814	if (xlog_check_buffer_cancelled(log, buf_f->blf_blkno,
2815			buf_f->blf_len, buf_f->blf_flags)) {
2816		trace_xfs_log_recover_buf_cancel(log, buf_f);
2817		return 0;
2818	}
2819
2820	trace_xfs_log_recover_buf_recover(log, buf_f);
2821
2822	buf_flags = 0;
2823	if (buf_f->blf_flags & XFS_BLF_INODE_BUF)
2824		buf_flags |= XBF_UNMAPPED;
2825
2826	bp = xfs_buf_read(mp->m_ddev_targp, buf_f->blf_blkno, buf_f->blf_len,
2827			  buf_flags, NULL);
2828	if (!bp)
2829		return -ENOMEM;
2830	error = bp->b_error;
2831	if (error) {
2832		xfs_buf_ioerror_alert(bp, "xlog_recover_do..(read#1)");
2833		goto out_release;
2834	}
2835
2836	/*
2837	 * Recover the buffer only if we get an LSN from it and it's less than
2838	 * the lsn of the transaction we are replaying.
2839	 *
2840	 * Note that we have to be extremely careful of readahead here.
2841	 * Readahead does not attach verfiers to the buffers so if we don't
2842	 * actually do any replay after readahead because of the LSN we found
2843	 * in the buffer if more recent than that current transaction then we
2844	 * need to attach the verifier directly. Failure to do so can lead to
2845	 * future recovery actions (e.g. EFI and unlinked list recovery) can
2846	 * operate on the buffers and they won't get the verifier attached. This
2847	 * can lead to blocks on disk having the correct content but a stale
2848	 * CRC.
2849	 *
2850	 * It is safe to assume these clean buffers are currently up to date.
2851	 * If the buffer is dirtied by a later transaction being replayed, then
2852	 * the verifier will be reset to match whatever recover turns that
2853	 * buffer into.
2854	 */
2855	lsn = xlog_recover_get_buf_lsn(mp, bp);
2856	if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) {
2857		trace_xfs_log_recover_buf_skip(log, buf_f);
2858		xlog_recover_validate_buf_type(mp, bp, buf_f, NULLCOMMITLSN);
2859		goto out_release;
2860	}
2861
2862	if (buf_f->blf_flags & XFS_BLF_INODE_BUF) {
2863		error = xlog_recover_do_inode_buffer(mp, item, bp, buf_f);
2864		if (error)
2865			goto out_release;
2866	} else if (buf_f->blf_flags &
2867		  (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) {
2868		bool	dirty;
2869
2870		dirty = xlog_recover_do_dquot_buffer(mp, log, item, bp, buf_f);
2871		if (!dirty)
2872			goto out_release;
2873	} else {
2874		xlog_recover_do_reg_buffer(mp, item, bp, buf_f, current_lsn);
2875	}
2876
2877	/*
2878	 * Perform delayed write on the buffer.  Asynchronous writes will be
2879	 * slower when taking into account all the buffers to be flushed.
2880	 *
2881	 * Also make sure that only inode buffers with good sizes stay in
2882	 * the buffer cache.  The kernel moves inodes in buffers of 1 block
2883	 * or mp->m_inode_cluster_size bytes, whichever is bigger.  The inode
2884	 * buffers in the log can be a different size if the log was generated
2885	 * by an older kernel using unclustered inode buffers or a newer kernel
2886	 * running with a different inode cluster size.  Regardless, if the
2887	 * the inode buffer size isn't MAX(blocksize, mp->m_inode_cluster_size)
2888	 * for *our* value of mp->m_inode_cluster_size, then we need to keep
2889	 * the buffer out of the buffer cache so that the buffer won't
2890	 * overlap with future reads of those inodes.
2891	 */
2892	if (XFS_DINODE_MAGIC ==
2893	    be16_to_cpu(*((__be16 *)xfs_buf_offset(bp, 0))) &&
2894	    (BBTOB(bp->b_io_length) != MAX(log->l_mp->m_sb.sb_blocksize,
2895			(uint32_t)log->l_mp->m_inode_cluster_size))) {
2896		xfs_buf_stale(bp);
2897		error = xfs_bwrite(bp);
2898	} else {
2899		ASSERT(bp->b_target->bt_mount == mp);
2900		bp->b_iodone = xlog_recover_iodone;
2901		xfs_buf_delwri_queue(bp, buffer_list);
2902	}
2903
2904out_release:
2905	xfs_buf_relse(bp);
2906	return error;
2907}
2908
2909/*
2910 * Inode fork owner changes
2911 *
2912 * If we have been told that we have to reparent the inode fork, it's because an
2913 * extent swap operation on a CRC enabled filesystem has been done and we are
2914 * replaying it. We need to walk the BMBT of the appropriate fork and change the
2915 * owners of it.
2916 *
2917 * The complexity here is that we don't have an inode context to work with, so
2918 * after we've replayed the inode we need to instantiate one.  This is where the
2919 * fun begins.
2920 *
2921 * We are in the middle of log recovery, so we can't run transactions. That
2922 * means we cannot use cache coherent inode instantiation via xfs_iget(), as
2923 * that will result in the corresponding iput() running the inode through
2924 * xfs_inactive(). If we've just replayed an inode core that changes the link
2925 * count to zero (i.e. it's been unlinked), then xfs_inactive() will run
2926 * transactions (bad!).
2927 *
2928 * So, to avoid this, we instantiate an inode directly from the inode core we've
2929 * just recovered. We have the buffer still locked, and all we really need to
2930 * instantiate is the inode core and the forks being modified. We can do this
2931 * manually, then run the inode btree owner change, and then tear down the
2932 * xfs_inode without having to run any transactions at all.
2933 *
2934 * Also, because we don't have a transaction context available here but need to
2935 * gather all the buffers we modify for writeback so we pass the buffer_list
2936 * instead for the operation to use.
2937 */
2938
2939STATIC int
2940xfs_recover_inode_owner_change(
2941	struct xfs_mount	*mp,
2942	struct xfs_dinode	*dip,
2943	struct xfs_inode_log_format *in_f,
2944	struct list_head	*buffer_list)
2945{
2946	struct xfs_inode	*ip;
2947	int			error;
2948
2949	ASSERT(in_f->ilf_fields & (XFS_ILOG_DOWNER|XFS_ILOG_AOWNER));
2950
2951	ip = xfs_inode_alloc(mp, in_f->ilf_ino);
2952	if (!ip)
2953		return -ENOMEM;
2954
2955	/* instantiate the inode */
2956	xfs_inode_from_disk(ip, dip);
2957	ASSERT(ip->i_d.di_version >= 3);
2958
2959	error = xfs_iformat_fork(ip, dip);
2960	if (error)
2961		goto out_free_ip;
2962
2963	if (!xfs_inode_verify_forks(ip)) {
2964		error = -EFSCORRUPTED;
2965		goto out_free_ip;
2966	}
2967
2968	if (in_f->ilf_fields & XFS_ILOG_DOWNER) {
2969		ASSERT(in_f->ilf_fields & XFS_ILOG_DBROOT);
2970		error = xfs_bmbt_change_owner(NULL, ip, XFS_DATA_FORK,
2971					      ip->i_ino, buffer_list);
2972		if (error)
2973			goto out_free_ip;
2974	}
2975
2976	if (in_f->ilf_fields & XFS_ILOG_AOWNER) {
2977		ASSERT(in_f->ilf_fields & XFS_ILOG_ABROOT);
2978		error = xfs_bmbt_change_owner(NULL, ip, XFS_ATTR_FORK,
2979					      ip->i_ino, buffer_list);
2980		if (error)
2981			goto out_free_ip;
2982	}
2983
2984out_free_ip:
2985	xfs_inode_free(ip);
2986	return error;
2987}
2988
2989STATIC int
2990xlog_recover_inode_pass2(
2991	struct xlog			*log,
2992	struct list_head		*buffer_list,
2993	struct xlog_recover_item	*item,
2994	xfs_lsn_t			current_lsn)
2995{
2996	struct xfs_inode_log_format	*in_f;
2997	xfs_mount_t		*mp = log->l_mp;
2998	xfs_buf_t		*bp;
2999	xfs_dinode_t		*dip;
3000	int			len;
3001	char			*src;
3002	char			*dest;
3003	int			error;
3004	int			attr_index;
3005	uint			fields;
3006	struct xfs_log_dinode	*ldip;
3007	uint			isize;
3008	int			need_free = 0;
3009
3010	if (item->ri_buf[0].i_len == sizeof(struct xfs_inode_log_format)) {
3011		in_f = item->ri_buf[0].i_addr;
3012	} else {
3013		in_f = kmem_alloc(sizeof(struct xfs_inode_log_format), KM_SLEEP);
3014		need_free = 1;
3015		error = xfs_inode_item_format_convert(&item->ri_buf[0], in_f);
3016		if (error)
3017			goto error;
3018	}
3019
3020	/*
3021	 * Inode buffers can be freed, look out for it,
3022	 * and do not replay the inode.
3023	 */
3024	if (xlog_check_buffer_cancelled(log, in_f->ilf_blkno,
3025					in_f->ilf_len, 0)) {
3026		error = 0;
3027		trace_xfs_log_recover_inode_cancel(log, in_f);
3028		goto error;
3029	}
3030	trace_xfs_log_recover_inode_recover(log, in_f);
3031
3032	bp = xfs_buf_read(mp->m_ddev_targp, in_f->ilf_blkno, in_f->ilf_len, 0,
3033			  &xfs_inode_buf_ops);
3034	if (!bp) {
3035		error = -ENOMEM;
3036		goto error;
3037	}
3038	error = bp->b_error;
3039	if (error) {
3040		xfs_buf_ioerror_alert(bp, "xlog_recover_do..(read#2)");
3041		goto out_release;
3042	}
3043	ASSERT(in_f->ilf_fields & XFS_ILOG_CORE);
3044	dip = xfs_buf_offset(bp, in_f->ilf_boffset);
3045
3046	/*
3047	 * Make sure the place we're flushing out to really looks
3048	 * like an inode!
3049	 */
3050	if (unlikely(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC))) {
3051		xfs_alert(mp,
3052	"%s: Bad inode magic number, dip = "PTR_FMT", dino bp = "PTR_FMT", ino = %Ld",
3053			__func__, dip, bp, in_f->ilf_ino);
3054		XFS_ERROR_REPORT("xlog_recover_inode_pass2(1)",
3055				 XFS_ERRLEVEL_LOW, mp);
3056		error = -EFSCORRUPTED;
3057		goto out_release;
3058	}
3059	ldip = item->ri_buf[1].i_addr;
3060	if (unlikely(ldip->di_magic != XFS_DINODE_MAGIC)) {
3061		xfs_alert(mp,
3062			"%s: Bad inode log record, rec ptr "PTR_FMT", ino %Ld",
3063			__func__, item, in_f->ilf_ino);
3064		XFS_ERROR_REPORT("xlog_recover_inode_pass2(2)",
3065				 XFS_ERRLEVEL_LOW, mp);
3066		error = -EFSCORRUPTED;
3067		goto out_release;
3068	}
3069
3070	/*
3071	 * If the inode has an LSN in it, recover the inode only if it's less
3072	 * than the lsn of the transaction we are replaying. Note: we still
3073	 * need to replay an owner change even though the inode is more recent
3074	 * than the transaction as there is no guarantee that all the btree
3075	 * blocks are more recent than this transaction, too.
3076	 */
3077	if (dip->di_version >= 3) {
3078		xfs_lsn_t	lsn = be64_to_cpu(dip->di_lsn);
3079
3080		if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) {
3081			trace_xfs_log_recover_inode_skip(log, in_f);
3082			error = 0;
3083			goto out_owner_change;
3084		}
3085	}
3086
3087	/*
3088	 * di_flushiter is only valid for v1/2 inodes. All changes for v3 inodes
3089	 * are transactional and if ordering is necessary we can determine that
3090	 * more accurately by the LSN field in the V3 inode core. Don't trust
3091	 * the inode versions we might be changing them here - use the
3092	 * superblock flag to determine whether we need to look at di_flushiter
3093	 * to skip replay when the on disk inode is newer than the log one
3094	 */
3095	if (!xfs_sb_version_hascrc(&mp->m_sb) &&
3096	    ldip->di_flushiter < be16_to_cpu(dip->di_flushiter)) {
3097		/*
3098		 * Deal with the wrap case, DI_MAX_FLUSH is less
3099		 * than smaller numbers
3100		 */
3101		if (be16_to_cpu(dip->di_flushiter) == DI_MAX_FLUSH &&
3102		    ldip->di_flushiter < (DI_MAX_FLUSH >> 1)) {
3103			/* do nothing */
3104		} else {
3105			trace_xfs_log_recover_inode_skip(log, in_f);
3106			error = 0;
3107			goto out_release;
3108		}
3109	}
3110
3111	/* Take the opportunity to reset the flush iteration count */
3112	ldip->di_flushiter = 0;
3113
3114	if (unlikely(S_ISREG(ldip->di_mode))) {
3115		if ((ldip->di_format != XFS_DINODE_FMT_EXTENTS) &&
3116		    (ldip->di_format != XFS_DINODE_FMT_BTREE)) {
3117			XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(3)",
3118					 XFS_ERRLEVEL_LOW, mp, ldip);
3119			xfs_alert(mp,
3120		"%s: Bad regular inode log record, rec ptr "PTR_FMT", "
3121		"ino ptr = "PTR_FMT", ino bp = "PTR_FMT", ino %Ld",
3122				__func__, item, dip, bp, in_f->ilf_ino);
3123			error = -EFSCORRUPTED;
3124			goto out_release;
3125		}
3126	} else if (unlikely(S_ISDIR(ldip->di_mode))) {
3127		if ((ldip->di_format != XFS_DINODE_FMT_EXTENTS) &&
3128		    (ldip->di_format != XFS_DINODE_FMT_BTREE) &&
3129		    (ldip->di_format != XFS_DINODE_FMT_LOCAL)) {
3130			XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(4)",
3131					     XFS_ERRLEVEL_LOW, mp, ldip);
3132			xfs_alert(mp,
3133		"%s: Bad dir inode log record, rec ptr "PTR_FMT", "
3134		"ino ptr = "PTR_FMT", ino bp = "PTR_FMT", ino %Ld",
3135				__func__, item, dip, bp, in_f->ilf_ino);
3136			error = -EFSCORRUPTED;
3137			goto out_release;
3138		}
3139	}
3140	if (unlikely(ldip->di_nextents + ldip->di_anextents > ldip->di_nblocks)){
3141		XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(5)",
3142				     XFS_ERRLEVEL_LOW, mp, ldip);
3143		xfs_alert(mp,
3144	"%s: Bad inode log record, rec ptr "PTR_FMT", dino ptr "PTR_FMT", "
3145	"dino bp "PTR_FMT", ino %Ld, total extents = %d, nblocks = %Ld",
3146			__func__, item, dip, bp, in_f->ilf_ino,
3147			ldip->di_nextents + ldip->di_anextents,
3148			ldip->di_nblocks);
3149		error = -EFSCORRUPTED;
3150		goto out_release;
3151	}
3152	if (unlikely(ldip->di_forkoff > mp->m_sb.sb_inodesize)) {
3153		XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(6)",
3154				     XFS_ERRLEVEL_LOW, mp, ldip);
3155		xfs_alert(mp,
3156	"%s: Bad inode log record, rec ptr "PTR_FMT", dino ptr "PTR_FMT", "
3157	"dino bp "PTR_FMT", ino %Ld, forkoff 0x%x", __func__,
3158			item, dip, bp, in_f->ilf_ino, ldip->di_forkoff);
3159		error = -EFSCORRUPTED;
3160		goto out_release;
3161	}
3162	isize = xfs_log_dinode_size(ldip->di_version);
3163	if (unlikely(item->ri_buf[1].i_len > isize)) {
3164		XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(7)",
3165				     XFS_ERRLEVEL_LOW, mp, ldip);
3166		xfs_alert(mp,
3167			"%s: Bad inode log record length %d, rec ptr "PTR_FMT,
3168			__func__, item->ri_buf[1].i_len, item);
3169		error = -EFSCORRUPTED;
3170		goto out_release;
3171	}
3172
3173	/* recover the log dinode inode into the on disk inode */
3174	xfs_log_dinode_to_disk(ldip, dip);
3175
 
 
 
 
 
 
 
3176	fields = in_f->ilf_fields;
3177	if (fields & XFS_ILOG_DEV)
 
3178		xfs_dinode_put_rdev(dip, in_f->ilf_u.ilfu_rdev);
 
 
 
 
 
 
 
3179
3180	if (in_f->ilf_size == 2)
3181		goto out_owner_change;
3182	len = item->ri_buf[2].i_len;
3183	src = item->ri_buf[2].i_addr;
3184	ASSERT(in_f->ilf_size <= 4);
3185	ASSERT((in_f->ilf_size == 3) || (fields & XFS_ILOG_AFORK));
3186	ASSERT(!(fields & XFS_ILOG_DFORK) ||
3187	       (len == in_f->ilf_dsize));
3188
3189	switch (fields & XFS_ILOG_DFORK) {
3190	case XFS_ILOG_DDATA:
3191	case XFS_ILOG_DEXT:
3192		memcpy(XFS_DFORK_DPTR(dip), src, len);
3193		break;
3194
3195	case XFS_ILOG_DBROOT:
3196		xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src, len,
3197				 (xfs_bmdr_block_t *)XFS_DFORK_DPTR(dip),
3198				 XFS_DFORK_DSIZE(dip, mp));
3199		break;
3200
3201	default:
3202		/*
3203		 * There are no data fork flags set.
3204		 */
3205		ASSERT((fields & XFS_ILOG_DFORK) == 0);
3206		break;
3207	}
3208
3209	/*
3210	 * If we logged any attribute data, recover it.  There may or
3211	 * may not have been any other non-core data logged in this
3212	 * transaction.
3213	 */
3214	if (in_f->ilf_fields & XFS_ILOG_AFORK) {
3215		if (in_f->ilf_fields & XFS_ILOG_DFORK) {
3216			attr_index = 3;
3217		} else {
3218			attr_index = 2;
3219		}
3220		len = item->ri_buf[attr_index].i_len;
3221		src = item->ri_buf[attr_index].i_addr;
3222		ASSERT(len == in_f->ilf_asize);
3223
3224		switch (in_f->ilf_fields & XFS_ILOG_AFORK) {
3225		case XFS_ILOG_ADATA:
3226		case XFS_ILOG_AEXT:
3227			dest = XFS_DFORK_APTR(dip);
3228			ASSERT(len <= XFS_DFORK_ASIZE(dip, mp));
3229			memcpy(dest, src, len);
3230			break;
3231
3232		case XFS_ILOG_ABROOT:
3233			dest = XFS_DFORK_APTR(dip);
3234			xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src,
3235					 len, (xfs_bmdr_block_t*)dest,
3236					 XFS_DFORK_ASIZE(dip, mp));
3237			break;
3238
3239		default:
3240			xfs_warn(log->l_mp, "%s: Invalid flag", __func__);
3241			ASSERT(0);
3242			error = -EIO;
3243			goto out_release;
3244		}
3245	}
3246
3247out_owner_change:
3248	/* Recover the swapext owner change unless inode has been deleted */
3249	if ((in_f->ilf_fields & (XFS_ILOG_DOWNER|XFS_ILOG_AOWNER)) &&
3250	    (dip->di_mode != 0))
3251		error = xfs_recover_inode_owner_change(mp, dip, in_f,
3252						       buffer_list);
3253	/* re-generate the checksum. */
3254	xfs_dinode_calc_crc(log->l_mp, dip);
3255
3256	ASSERT(bp->b_target->bt_mount == mp);
3257	bp->b_iodone = xlog_recover_iodone;
3258	xfs_buf_delwri_queue(bp, buffer_list);
3259
3260out_release:
3261	xfs_buf_relse(bp);
3262error:
3263	if (need_free)
3264		kmem_free(in_f);
3265	return error;
3266}
3267
3268/*
3269 * Recover QUOTAOFF records. We simply make a note of it in the xlog
3270 * structure, so that we know not to do any dquot item or dquot buffer recovery,
3271 * of that type.
3272 */
3273STATIC int
3274xlog_recover_quotaoff_pass1(
3275	struct xlog			*log,
3276	struct xlog_recover_item	*item)
3277{
3278	xfs_qoff_logformat_t	*qoff_f = item->ri_buf[0].i_addr;
3279	ASSERT(qoff_f);
3280
3281	/*
3282	 * The logitem format's flag tells us if this was user quotaoff,
3283	 * group/project quotaoff or both.
3284	 */
3285	if (qoff_f->qf_flags & XFS_UQUOTA_ACCT)
3286		log->l_quotaoffs_flag |= XFS_DQ_USER;
3287	if (qoff_f->qf_flags & XFS_PQUOTA_ACCT)
3288		log->l_quotaoffs_flag |= XFS_DQ_PROJ;
3289	if (qoff_f->qf_flags & XFS_GQUOTA_ACCT)
3290		log->l_quotaoffs_flag |= XFS_DQ_GROUP;
3291
3292	return 0;
3293}
3294
3295/*
3296 * Recover a dquot record
3297 */
3298STATIC int
3299xlog_recover_dquot_pass2(
3300	struct xlog			*log,
3301	struct list_head		*buffer_list,
3302	struct xlog_recover_item	*item,
3303	xfs_lsn_t			current_lsn)
3304{
3305	xfs_mount_t		*mp = log->l_mp;
3306	xfs_buf_t		*bp;
3307	struct xfs_disk_dquot	*ddq, *recddq;
3308	xfs_failaddr_t		fa;
3309	int			error;
3310	xfs_dq_logformat_t	*dq_f;
3311	uint			type;
3312
3313
3314	/*
3315	 * Filesystems are required to send in quota flags at mount time.
3316	 */
3317	if (mp->m_qflags == 0)
3318		return 0;
3319
3320	recddq = item->ri_buf[1].i_addr;
3321	if (recddq == NULL) {
3322		xfs_alert(log->l_mp, "NULL dquot in %s.", __func__);
3323		return -EIO;
3324	}
3325	if (item->ri_buf[1].i_len < sizeof(xfs_disk_dquot_t)) {
3326		xfs_alert(log->l_mp, "dquot too small (%d) in %s.",
3327			item->ri_buf[1].i_len, __func__);
3328		return -EIO;
3329	}
3330
3331	/*
3332	 * This type of quotas was turned off, so ignore this record.
3333	 */
3334	type = recddq->d_flags & (XFS_DQ_USER | XFS_DQ_PROJ | XFS_DQ_GROUP);
3335	ASSERT(type);
3336	if (log->l_quotaoffs_flag & type)
3337		return 0;
3338
3339	/*
3340	 * At this point we know that quota was _not_ turned off.
3341	 * Since the mount flags are not indicating to us otherwise, this
3342	 * must mean that quota is on, and the dquot needs to be replayed.
3343	 * Remember that we may not have fully recovered the superblock yet,
3344	 * so we can't do the usual trick of looking at the SB quota bits.
3345	 *
3346	 * The other possibility, of course, is that the quota subsystem was
3347	 * removed since the last mount - ENOSYS.
3348	 */
3349	dq_f = item->ri_buf[0].i_addr;
3350	ASSERT(dq_f);
3351	fa = xfs_dquot_verify(mp, recddq, dq_f->qlf_id, 0, 0);
3352	if (fa) {
3353		xfs_alert(mp, "corrupt dquot ID 0x%x in log at %pS",
3354				dq_f->qlf_id, fa);
3355		return -EIO;
3356	}
3357	ASSERT(dq_f->qlf_len == 1);
3358
3359	/*
3360	 * At this point we are assuming that the dquots have been allocated
3361	 * and hence the buffer has valid dquots stamped in it. It should,
3362	 * therefore, pass verifier validation. If the dquot is bad, then the
3363	 * we'll return an error here, so we don't need to specifically check
3364	 * the dquot in the buffer after the verifier has run.
3365	 */
3366	error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dq_f->qlf_blkno,
3367				   XFS_FSB_TO_BB(mp, dq_f->qlf_len), 0, &bp,
3368				   &xfs_dquot_buf_ops);
3369	if (error)
3370		return error;
3371
3372	ASSERT(bp);
3373	ddq = xfs_buf_offset(bp, dq_f->qlf_boffset);
3374
3375	/*
3376	 * If the dquot has an LSN in it, recover the dquot only if it's less
3377	 * than the lsn of the transaction we are replaying.
3378	 */
3379	if (xfs_sb_version_hascrc(&mp->m_sb)) {
3380		struct xfs_dqblk *dqb = (struct xfs_dqblk *)ddq;
3381		xfs_lsn_t	lsn = be64_to_cpu(dqb->dd_lsn);
3382
3383		if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) {
3384			goto out_release;
3385		}
3386	}
3387
3388	memcpy(ddq, recddq, item->ri_buf[1].i_len);
3389	if (xfs_sb_version_hascrc(&mp->m_sb)) {
3390		xfs_update_cksum((char *)ddq, sizeof(struct xfs_dqblk),
3391				 XFS_DQUOT_CRC_OFF);
3392	}
3393
3394	ASSERT(dq_f->qlf_size == 2);
3395	ASSERT(bp->b_target->bt_mount == mp);
3396	bp->b_iodone = xlog_recover_iodone;
3397	xfs_buf_delwri_queue(bp, buffer_list);
3398
3399out_release:
3400	xfs_buf_relse(bp);
3401	return 0;
3402}
3403
3404/*
3405 * This routine is called to create an in-core extent free intent
3406 * item from the efi format structure which was logged on disk.
3407 * It allocates an in-core efi, copies the extents from the format
3408 * structure into it, and adds the efi to the AIL with the given
3409 * LSN.
3410 */
3411STATIC int
3412xlog_recover_efi_pass2(
3413	struct xlog			*log,
3414	struct xlog_recover_item	*item,
3415	xfs_lsn_t			lsn)
3416{
3417	int				error;
3418	struct xfs_mount		*mp = log->l_mp;
3419	struct xfs_efi_log_item		*efip;
3420	struct xfs_efi_log_format	*efi_formatp;
3421
3422	efi_formatp = item->ri_buf[0].i_addr;
3423
3424	efip = xfs_efi_init(mp, efi_formatp->efi_nextents);
3425	error = xfs_efi_copy_format(&item->ri_buf[0], &efip->efi_format);
3426	if (error) {
3427		xfs_efi_item_free(efip);
3428		return error;
3429	}
3430	atomic_set(&efip->efi_next_extent, efi_formatp->efi_nextents);
3431
3432	spin_lock(&log->l_ailp->ail_lock);
3433	/*
3434	 * The EFI has two references. One for the EFD and one for EFI to ensure
3435	 * it makes it into the AIL. Insert the EFI into the AIL directly and
3436	 * drop the EFI reference. Note that xfs_trans_ail_update() drops the
3437	 * AIL lock.
3438	 */
3439	xfs_trans_ail_update(log->l_ailp, &efip->efi_item, lsn);
3440	xfs_efi_release(efip);
3441	return 0;
3442}
3443
3444
3445/*
3446 * This routine is called when an EFD format structure is found in a committed
3447 * transaction in the log. Its purpose is to cancel the corresponding EFI if it
3448 * was still in the log. To do this it searches the AIL for the EFI with an id
3449 * equal to that in the EFD format structure. If we find it we drop the EFD
3450 * reference, which removes the EFI from the AIL and frees it.
3451 */
3452STATIC int
3453xlog_recover_efd_pass2(
3454	struct xlog			*log,
3455	struct xlog_recover_item	*item)
3456{
3457	xfs_efd_log_format_t	*efd_formatp;
3458	xfs_efi_log_item_t	*efip = NULL;
3459	xfs_log_item_t		*lip;
3460	uint64_t		efi_id;
3461	struct xfs_ail_cursor	cur;
3462	struct xfs_ail		*ailp = log->l_ailp;
3463
3464	efd_formatp = item->ri_buf[0].i_addr;
3465	ASSERT((item->ri_buf[0].i_len == (sizeof(xfs_efd_log_format_32_t) +
3466		((efd_formatp->efd_nextents - 1) * sizeof(xfs_extent_32_t)))) ||
3467	       (item->ri_buf[0].i_len == (sizeof(xfs_efd_log_format_64_t) +
3468		((efd_formatp->efd_nextents - 1) * sizeof(xfs_extent_64_t)))));
3469	efi_id = efd_formatp->efd_efi_id;
3470
3471	/*
3472	 * Search for the EFI with the id in the EFD format structure in the
3473	 * AIL.
3474	 */
3475	spin_lock(&ailp->ail_lock);
3476	lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3477	while (lip != NULL) {
3478		if (lip->li_type == XFS_LI_EFI) {
3479			efip = (xfs_efi_log_item_t *)lip;
3480			if (efip->efi_format.efi_id == efi_id) {
3481				/*
3482				 * Drop the EFD reference to the EFI. This
3483				 * removes the EFI from the AIL and frees it.
3484				 */
3485				spin_unlock(&ailp->ail_lock);
3486				xfs_efi_release(efip);
3487				spin_lock(&ailp->ail_lock);
3488				break;
3489			}
3490		}
3491		lip = xfs_trans_ail_cursor_next(ailp, &cur);
3492	}
3493
3494	xfs_trans_ail_cursor_done(&cur);
3495	spin_unlock(&ailp->ail_lock);
3496
3497	return 0;
3498}
3499
3500/*
3501 * This routine is called to create an in-core extent rmap update
3502 * item from the rui format structure which was logged on disk.
3503 * It allocates an in-core rui, copies the extents from the format
3504 * structure into it, and adds the rui to the AIL with the given
3505 * LSN.
3506 */
3507STATIC int
3508xlog_recover_rui_pass2(
3509	struct xlog			*log,
3510	struct xlog_recover_item	*item,
3511	xfs_lsn_t			lsn)
3512{
3513	int				error;
3514	struct xfs_mount		*mp = log->l_mp;
3515	struct xfs_rui_log_item		*ruip;
3516	struct xfs_rui_log_format	*rui_formatp;
3517
3518	rui_formatp = item->ri_buf[0].i_addr;
3519
3520	ruip = xfs_rui_init(mp, rui_formatp->rui_nextents);
3521	error = xfs_rui_copy_format(&item->ri_buf[0], &ruip->rui_format);
3522	if (error) {
3523		xfs_rui_item_free(ruip);
3524		return error;
3525	}
3526	atomic_set(&ruip->rui_next_extent, rui_formatp->rui_nextents);
3527
3528	spin_lock(&log->l_ailp->ail_lock);
3529	/*
3530	 * The RUI has two references. One for the RUD and one for RUI to ensure
3531	 * it makes it into the AIL. Insert the RUI into the AIL directly and
3532	 * drop the RUI reference. Note that xfs_trans_ail_update() drops the
3533	 * AIL lock.
3534	 */
3535	xfs_trans_ail_update(log->l_ailp, &ruip->rui_item, lsn);
3536	xfs_rui_release(ruip);
3537	return 0;
3538}
3539
3540
3541/*
3542 * This routine is called when an RUD format structure is found in a committed
3543 * transaction in the log. Its purpose is to cancel the corresponding RUI if it
3544 * was still in the log. To do this it searches the AIL for the RUI with an id
3545 * equal to that in the RUD format structure. If we find it we drop the RUD
3546 * reference, which removes the RUI from the AIL and frees it.
3547 */
3548STATIC int
3549xlog_recover_rud_pass2(
3550	struct xlog			*log,
3551	struct xlog_recover_item	*item)
3552{
3553	struct xfs_rud_log_format	*rud_formatp;
3554	struct xfs_rui_log_item		*ruip = NULL;
3555	struct xfs_log_item		*lip;
3556	uint64_t			rui_id;
3557	struct xfs_ail_cursor		cur;
3558	struct xfs_ail			*ailp = log->l_ailp;
3559
3560	rud_formatp = item->ri_buf[0].i_addr;
3561	ASSERT(item->ri_buf[0].i_len == sizeof(struct xfs_rud_log_format));
3562	rui_id = rud_formatp->rud_rui_id;
3563
3564	/*
3565	 * Search for the RUI with the id in the RUD format structure in the
3566	 * AIL.
3567	 */
3568	spin_lock(&ailp->ail_lock);
3569	lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3570	while (lip != NULL) {
3571		if (lip->li_type == XFS_LI_RUI) {
3572			ruip = (struct xfs_rui_log_item *)lip;
3573			if (ruip->rui_format.rui_id == rui_id) {
3574				/*
3575				 * Drop the RUD reference to the RUI. This
3576				 * removes the RUI from the AIL and frees it.
3577				 */
3578				spin_unlock(&ailp->ail_lock);
3579				xfs_rui_release(ruip);
3580				spin_lock(&ailp->ail_lock);
3581				break;
3582			}
3583		}
3584		lip = xfs_trans_ail_cursor_next(ailp, &cur);
3585	}
3586
3587	xfs_trans_ail_cursor_done(&cur);
3588	spin_unlock(&ailp->ail_lock);
3589
3590	return 0;
3591}
3592
3593/*
3594 * Copy an CUI format buffer from the given buf, and into the destination
3595 * CUI format structure.  The CUI/CUD items were designed not to need any
3596 * special alignment handling.
3597 */
3598static int
3599xfs_cui_copy_format(
3600	struct xfs_log_iovec		*buf,
3601	struct xfs_cui_log_format	*dst_cui_fmt)
3602{
3603	struct xfs_cui_log_format	*src_cui_fmt;
3604	uint				len;
3605
3606	src_cui_fmt = buf->i_addr;
3607	len = xfs_cui_log_format_sizeof(src_cui_fmt->cui_nextents);
3608
3609	if (buf->i_len == len) {
3610		memcpy(dst_cui_fmt, src_cui_fmt, len);
3611		return 0;
3612	}
3613	return -EFSCORRUPTED;
3614}
3615
3616/*
3617 * This routine is called to create an in-core extent refcount update
3618 * item from the cui format structure which was logged on disk.
3619 * It allocates an in-core cui, copies the extents from the format
3620 * structure into it, and adds the cui to the AIL with the given
3621 * LSN.
3622 */
3623STATIC int
3624xlog_recover_cui_pass2(
3625	struct xlog			*log,
3626	struct xlog_recover_item	*item,
3627	xfs_lsn_t			lsn)
3628{
3629	int				error;
3630	struct xfs_mount		*mp = log->l_mp;
3631	struct xfs_cui_log_item		*cuip;
3632	struct xfs_cui_log_format	*cui_formatp;
3633
3634	cui_formatp = item->ri_buf[0].i_addr;
3635
3636	cuip = xfs_cui_init(mp, cui_formatp->cui_nextents);
3637	error = xfs_cui_copy_format(&item->ri_buf[0], &cuip->cui_format);
3638	if (error) {
3639		xfs_cui_item_free(cuip);
3640		return error;
3641	}
3642	atomic_set(&cuip->cui_next_extent, cui_formatp->cui_nextents);
3643
3644	spin_lock(&log->l_ailp->ail_lock);
3645	/*
3646	 * The CUI has two references. One for the CUD and one for CUI to ensure
3647	 * it makes it into the AIL. Insert the CUI into the AIL directly and
3648	 * drop the CUI reference. Note that xfs_trans_ail_update() drops the
3649	 * AIL lock.
3650	 */
3651	xfs_trans_ail_update(log->l_ailp, &cuip->cui_item, lsn);
3652	xfs_cui_release(cuip);
3653	return 0;
3654}
3655
3656
3657/*
3658 * This routine is called when an CUD format structure is found in a committed
3659 * transaction in the log. Its purpose is to cancel the corresponding CUI if it
3660 * was still in the log. To do this it searches the AIL for the CUI with an id
3661 * equal to that in the CUD format structure. If we find it we drop the CUD
3662 * reference, which removes the CUI from the AIL and frees it.
3663 */
3664STATIC int
3665xlog_recover_cud_pass2(
3666	struct xlog			*log,
3667	struct xlog_recover_item	*item)
3668{
3669	struct xfs_cud_log_format	*cud_formatp;
3670	struct xfs_cui_log_item		*cuip = NULL;
3671	struct xfs_log_item		*lip;
3672	uint64_t			cui_id;
3673	struct xfs_ail_cursor		cur;
3674	struct xfs_ail			*ailp = log->l_ailp;
3675
3676	cud_formatp = item->ri_buf[0].i_addr;
3677	if (item->ri_buf[0].i_len != sizeof(struct xfs_cud_log_format))
3678		return -EFSCORRUPTED;
3679	cui_id = cud_formatp->cud_cui_id;
3680
3681	/*
3682	 * Search for the CUI with the id in the CUD format structure in the
3683	 * AIL.
3684	 */
3685	spin_lock(&ailp->ail_lock);
3686	lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3687	while (lip != NULL) {
3688		if (lip->li_type == XFS_LI_CUI) {
3689			cuip = (struct xfs_cui_log_item *)lip;
3690			if (cuip->cui_format.cui_id == cui_id) {
3691				/*
3692				 * Drop the CUD reference to the CUI. This
3693				 * removes the CUI from the AIL and frees it.
3694				 */
3695				spin_unlock(&ailp->ail_lock);
3696				xfs_cui_release(cuip);
3697				spin_lock(&ailp->ail_lock);
3698				break;
3699			}
3700		}
3701		lip = xfs_trans_ail_cursor_next(ailp, &cur);
3702	}
3703
3704	xfs_trans_ail_cursor_done(&cur);
3705	spin_unlock(&ailp->ail_lock);
3706
3707	return 0;
3708}
3709
3710/*
3711 * Copy an BUI format buffer from the given buf, and into the destination
3712 * BUI format structure.  The BUI/BUD items were designed not to need any
3713 * special alignment handling.
3714 */
3715static int
3716xfs_bui_copy_format(
3717	struct xfs_log_iovec		*buf,
3718	struct xfs_bui_log_format	*dst_bui_fmt)
3719{
3720	struct xfs_bui_log_format	*src_bui_fmt;
3721	uint				len;
3722
3723	src_bui_fmt = buf->i_addr;
3724	len = xfs_bui_log_format_sizeof(src_bui_fmt->bui_nextents);
3725
3726	if (buf->i_len == len) {
3727		memcpy(dst_bui_fmt, src_bui_fmt, len);
3728		return 0;
3729	}
3730	return -EFSCORRUPTED;
3731}
3732
3733/*
3734 * This routine is called to create an in-core extent bmap update
3735 * item from the bui format structure which was logged on disk.
3736 * It allocates an in-core bui, copies the extents from the format
3737 * structure into it, and adds the bui to the AIL with the given
3738 * LSN.
3739 */
3740STATIC int
3741xlog_recover_bui_pass2(
3742	struct xlog			*log,
3743	struct xlog_recover_item	*item,
3744	xfs_lsn_t			lsn)
3745{
3746	int				error;
3747	struct xfs_mount		*mp = log->l_mp;
3748	struct xfs_bui_log_item		*buip;
3749	struct xfs_bui_log_format	*bui_formatp;
3750
3751	bui_formatp = item->ri_buf[0].i_addr;
3752
3753	if (bui_formatp->bui_nextents != XFS_BUI_MAX_FAST_EXTENTS)
3754		return -EFSCORRUPTED;
3755	buip = xfs_bui_init(mp);
3756	error = xfs_bui_copy_format(&item->ri_buf[0], &buip->bui_format);
3757	if (error) {
3758		xfs_bui_item_free(buip);
3759		return error;
3760	}
3761	atomic_set(&buip->bui_next_extent, bui_formatp->bui_nextents);
3762
3763	spin_lock(&log->l_ailp->ail_lock);
3764	/*
3765	 * The RUI has two references. One for the RUD and one for RUI to ensure
3766	 * it makes it into the AIL. Insert the RUI into the AIL directly and
3767	 * drop the RUI reference. Note that xfs_trans_ail_update() drops the
3768	 * AIL lock.
3769	 */
3770	xfs_trans_ail_update(log->l_ailp, &buip->bui_item, lsn);
3771	xfs_bui_release(buip);
3772	return 0;
3773}
3774
3775
3776/*
3777 * This routine is called when an BUD format structure is found in a committed
3778 * transaction in the log. Its purpose is to cancel the corresponding BUI if it
3779 * was still in the log. To do this it searches the AIL for the BUI with an id
3780 * equal to that in the BUD format structure. If we find it we drop the BUD
3781 * reference, which removes the BUI from the AIL and frees it.
3782 */
3783STATIC int
3784xlog_recover_bud_pass2(
3785	struct xlog			*log,
3786	struct xlog_recover_item	*item)
3787{
3788	struct xfs_bud_log_format	*bud_formatp;
3789	struct xfs_bui_log_item		*buip = NULL;
3790	struct xfs_log_item		*lip;
3791	uint64_t			bui_id;
3792	struct xfs_ail_cursor		cur;
3793	struct xfs_ail			*ailp = log->l_ailp;
3794
3795	bud_formatp = item->ri_buf[0].i_addr;
3796	if (item->ri_buf[0].i_len != sizeof(struct xfs_bud_log_format))
3797		return -EFSCORRUPTED;
3798	bui_id = bud_formatp->bud_bui_id;
3799
3800	/*
3801	 * Search for the BUI with the id in the BUD format structure in the
3802	 * AIL.
3803	 */
3804	spin_lock(&ailp->ail_lock);
3805	lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3806	while (lip != NULL) {
3807		if (lip->li_type == XFS_LI_BUI) {
3808			buip = (struct xfs_bui_log_item *)lip;
3809			if (buip->bui_format.bui_id == bui_id) {
3810				/*
3811				 * Drop the BUD reference to the BUI. This
3812				 * removes the BUI from the AIL and frees it.
3813				 */
3814				spin_unlock(&ailp->ail_lock);
3815				xfs_bui_release(buip);
3816				spin_lock(&ailp->ail_lock);
3817				break;
3818			}
3819		}
3820		lip = xfs_trans_ail_cursor_next(ailp, &cur);
3821	}
3822
3823	xfs_trans_ail_cursor_done(&cur);
3824	spin_unlock(&ailp->ail_lock);
3825
3826	return 0;
3827}
3828
3829/*
3830 * This routine is called when an inode create format structure is found in a
3831 * committed transaction in the log.  It's purpose is to initialise the inodes
3832 * being allocated on disk. This requires us to get inode cluster buffers that
3833 * match the range to be initialised, stamped with inode templates and written
3834 * by delayed write so that subsequent modifications will hit the cached buffer
3835 * and only need writing out at the end of recovery.
3836 */
3837STATIC int
3838xlog_recover_do_icreate_pass2(
3839	struct xlog		*log,
3840	struct list_head	*buffer_list,
3841	xlog_recover_item_t	*item)
3842{
3843	struct xfs_mount	*mp = log->l_mp;
3844	struct xfs_icreate_log	*icl;
3845	xfs_agnumber_t		agno;
3846	xfs_agblock_t		agbno;
3847	unsigned int		count;
3848	unsigned int		isize;
3849	xfs_agblock_t		length;
3850	int			blks_per_cluster;
3851	int			bb_per_cluster;
3852	int			cancel_count;
3853	int			nbufs;
3854	int			i;
3855
3856	icl = (struct xfs_icreate_log *)item->ri_buf[0].i_addr;
3857	if (icl->icl_type != XFS_LI_ICREATE) {
3858		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad type");
3859		return -EINVAL;
3860	}
3861
3862	if (icl->icl_size != 1) {
3863		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad icl size");
3864		return -EINVAL;
3865	}
3866
3867	agno = be32_to_cpu(icl->icl_ag);
3868	if (agno >= mp->m_sb.sb_agcount) {
3869		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad agno");
3870		return -EINVAL;
3871	}
3872	agbno = be32_to_cpu(icl->icl_agbno);
3873	if (!agbno || agbno == NULLAGBLOCK || agbno >= mp->m_sb.sb_agblocks) {
3874		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad agbno");
3875		return -EINVAL;
3876	}
3877	isize = be32_to_cpu(icl->icl_isize);
3878	if (isize != mp->m_sb.sb_inodesize) {
3879		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad isize");
3880		return -EINVAL;
3881	}
3882	count = be32_to_cpu(icl->icl_count);
3883	if (!count) {
3884		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad count");
3885		return -EINVAL;
3886	}
3887	length = be32_to_cpu(icl->icl_length);
3888	if (!length || length >= mp->m_sb.sb_agblocks) {
3889		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad length");
3890		return -EINVAL;
3891	}
3892
3893	/*
3894	 * The inode chunk is either full or sparse and we only support
3895	 * m_ialloc_min_blks sized sparse allocations at this time.
3896	 */
3897	if (length != mp->m_ialloc_blks &&
3898	    length != mp->m_ialloc_min_blks) {
3899		xfs_warn(log->l_mp,
3900			 "%s: unsupported chunk length", __FUNCTION__);
3901		return -EINVAL;
3902	}
3903
3904	/* verify inode count is consistent with extent length */
3905	if ((count >> mp->m_sb.sb_inopblog) != length) {
3906		xfs_warn(log->l_mp,
3907			 "%s: inconsistent inode count and chunk length",
3908			 __FUNCTION__);
3909		return -EINVAL;
3910	}
3911
3912	/*
3913	 * The icreate transaction can cover multiple cluster buffers and these
3914	 * buffers could have been freed and reused. Check the individual
3915	 * buffers for cancellation so we don't overwrite anything written after
3916	 * a cancellation.
3917	 */
3918	blks_per_cluster = xfs_icluster_size_fsb(mp);
3919	bb_per_cluster = XFS_FSB_TO_BB(mp, blks_per_cluster);
3920	nbufs = length / blks_per_cluster;
3921	for (i = 0, cancel_count = 0; i < nbufs; i++) {
3922		xfs_daddr_t	daddr;
3923
3924		daddr = XFS_AGB_TO_DADDR(mp, agno,
3925					 agbno + i * blks_per_cluster);
3926		if (xlog_check_buffer_cancelled(log, daddr, bb_per_cluster, 0))
3927			cancel_count++;
3928	}
3929
3930	/*
3931	 * We currently only use icreate for a single allocation at a time. This
3932	 * means we should expect either all or none of the buffers to be
3933	 * cancelled. Be conservative and skip replay if at least one buffer is
3934	 * cancelled, but warn the user that something is awry if the buffers
3935	 * are not consistent.
3936	 *
3937	 * XXX: This must be refined to only skip cancelled clusters once we use
3938	 * icreate for multiple chunk allocations.
3939	 */
3940	ASSERT(!cancel_count || cancel_count == nbufs);
3941	if (cancel_count) {
3942		if (cancel_count != nbufs)
3943			xfs_warn(mp,
3944	"WARNING: partial inode chunk cancellation, skipped icreate.");
3945		trace_xfs_log_recover_icreate_cancel(log, icl);
3946		return 0;
3947	}
3948
3949	trace_xfs_log_recover_icreate_recover(log, icl);
3950	return xfs_ialloc_inode_init(mp, NULL, buffer_list, count, agno, agbno,
3951				     length, be32_to_cpu(icl->icl_gen));
3952}
3953
3954STATIC void
3955xlog_recover_buffer_ra_pass2(
3956	struct xlog                     *log,
3957	struct xlog_recover_item        *item)
3958{
3959	struct xfs_buf_log_format	*buf_f = item->ri_buf[0].i_addr;
3960	struct xfs_mount		*mp = log->l_mp;
3961
3962	if (xlog_peek_buffer_cancelled(log, buf_f->blf_blkno,
3963			buf_f->blf_len, buf_f->blf_flags)) {
3964		return;
3965	}
3966
3967	xfs_buf_readahead(mp->m_ddev_targp, buf_f->blf_blkno,
3968				buf_f->blf_len, NULL);
3969}
3970
3971STATIC void
3972xlog_recover_inode_ra_pass2(
3973	struct xlog                     *log,
3974	struct xlog_recover_item        *item)
3975{
3976	struct xfs_inode_log_format	ilf_buf;
3977	struct xfs_inode_log_format	*ilfp;
3978	struct xfs_mount		*mp = log->l_mp;
3979	int			error;
3980
3981	if (item->ri_buf[0].i_len == sizeof(struct xfs_inode_log_format)) {
3982		ilfp = item->ri_buf[0].i_addr;
3983	} else {
3984		ilfp = &ilf_buf;
3985		memset(ilfp, 0, sizeof(*ilfp));
3986		error = xfs_inode_item_format_convert(&item->ri_buf[0], ilfp);
3987		if (error)
3988			return;
3989	}
3990
3991	if (xlog_peek_buffer_cancelled(log, ilfp->ilf_blkno, ilfp->ilf_len, 0))
3992		return;
3993
3994	xfs_buf_readahead(mp->m_ddev_targp, ilfp->ilf_blkno,
3995				ilfp->ilf_len, &xfs_inode_buf_ra_ops);
3996}
3997
3998STATIC void
3999xlog_recover_dquot_ra_pass2(
4000	struct xlog			*log,
4001	struct xlog_recover_item	*item)
4002{
4003	struct xfs_mount	*mp = log->l_mp;
4004	struct xfs_disk_dquot	*recddq;
4005	struct xfs_dq_logformat	*dq_f;
4006	uint			type;
4007	int			len;
4008
4009
4010	if (mp->m_qflags == 0)
4011		return;
4012
4013	recddq = item->ri_buf[1].i_addr;
4014	if (recddq == NULL)
4015		return;
4016	if (item->ri_buf[1].i_len < sizeof(struct xfs_disk_dquot))
4017		return;
4018
4019	type = recddq->d_flags & (XFS_DQ_USER | XFS_DQ_PROJ | XFS_DQ_GROUP);
4020	ASSERT(type);
4021	if (log->l_quotaoffs_flag & type)
4022		return;
4023
4024	dq_f = item->ri_buf[0].i_addr;
4025	ASSERT(dq_f);
4026	ASSERT(dq_f->qlf_len == 1);
4027
4028	len = XFS_FSB_TO_BB(mp, dq_f->qlf_len);
4029	if (xlog_peek_buffer_cancelled(log, dq_f->qlf_blkno, len, 0))
4030		return;
4031
4032	xfs_buf_readahead(mp->m_ddev_targp, dq_f->qlf_blkno, len,
4033			  &xfs_dquot_buf_ra_ops);
4034}
4035
4036STATIC void
4037xlog_recover_ra_pass2(
4038	struct xlog			*log,
4039	struct xlog_recover_item	*item)
4040{
4041	switch (ITEM_TYPE(item)) {
4042	case XFS_LI_BUF:
4043		xlog_recover_buffer_ra_pass2(log, item);
4044		break;
4045	case XFS_LI_INODE:
4046		xlog_recover_inode_ra_pass2(log, item);
4047		break;
4048	case XFS_LI_DQUOT:
4049		xlog_recover_dquot_ra_pass2(log, item);
4050		break;
4051	case XFS_LI_EFI:
4052	case XFS_LI_EFD:
4053	case XFS_LI_QUOTAOFF:
4054	case XFS_LI_RUI:
4055	case XFS_LI_RUD:
4056	case XFS_LI_CUI:
4057	case XFS_LI_CUD:
4058	case XFS_LI_BUI:
4059	case XFS_LI_BUD:
4060	default:
4061		break;
4062	}
4063}
4064
4065STATIC int
4066xlog_recover_commit_pass1(
4067	struct xlog			*log,
4068	struct xlog_recover		*trans,
4069	struct xlog_recover_item	*item)
4070{
4071	trace_xfs_log_recover_item_recover(log, trans, item, XLOG_RECOVER_PASS1);
4072
4073	switch (ITEM_TYPE(item)) {
4074	case XFS_LI_BUF:
4075		return xlog_recover_buffer_pass1(log, item);
4076	case XFS_LI_QUOTAOFF:
4077		return xlog_recover_quotaoff_pass1(log, item);
4078	case XFS_LI_INODE:
4079	case XFS_LI_EFI:
4080	case XFS_LI_EFD:
4081	case XFS_LI_DQUOT:
4082	case XFS_LI_ICREATE:
4083	case XFS_LI_RUI:
4084	case XFS_LI_RUD:
4085	case XFS_LI_CUI:
4086	case XFS_LI_CUD:
4087	case XFS_LI_BUI:
4088	case XFS_LI_BUD:
4089		/* nothing to do in pass 1 */
4090		return 0;
4091	default:
4092		xfs_warn(log->l_mp, "%s: invalid item type (%d)",
4093			__func__, ITEM_TYPE(item));
4094		ASSERT(0);
4095		return -EIO;
4096	}
4097}
4098
4099STATIC int
4100xlog_recover_commit_pass2(
4101	struct xlog			*log,
4102	struct xlog_recover		*trans,
4103	struct list_head		*buffer_list,
4104	struct xlog_recover_item	*item)
4105{
4106	trace_xfs_log_recover_item_recover(log, trans, item, XLOG_RECOVER_PASS2);
4107
4108	switch (ITEM_TYPE(item)) {
4109	case XFS_LI_BUF:
4110		return xlog_recover_buffer_pass2(log, buffer_list, item,
4111						 trans->r_lsn);
4112	case XFS_LI_INODE:
4113		return xlog_recover_inode_pass2(log, buffer_list, item,
4114						 trans->r_lsn);
4115	case XFS_LI_EFI:
4116		return xlog_recover_efi_pass2(log, item, trans->r_lsn);
4117	case XFS_LI_EFD:
4118		return xlog_recover_efd_pass2(log, item);
4119	case XFS_LI_RUI:
4120		return xlog_recover_rui_pass2(log, item, trans->r_lsn);
4121	case XFS_LI_RUD:
4122		return xlog_recover_rud_pass2(log, item);
4123	case XFS_LI_CUI:
4124		return xlog_recover_cui_pass2(log, item, trans->r_lsn);
4125	case XFS_LI_CUD:
4126		return xlog_recover_cud_pass2(log, item);
4127	case XFS_LI_BUI:
4128		return xlog_recover_bui_pass2(log, item, trans->r_lsn);
4129	case XFS_LI_BUD:
4130		return xlog_recover_bud_pass2(log, item);
4131	case XFS_LI_DQUOT:
4132		return xlog_recover_dquot_pass2(log, buffer_list, item,
4133						trans->r_lsn);
4134	case XFS_LI_ICREATE:
4135		return xlog_recover_do_icreate_pass2(log, buffer_list, item);
4136	case XFS_LI_QUOTAOFF:
4137		/* nothing to do in pass2 */
4138		return 0;
4139	default:
4140		xfs_warn(log->l_mp, "%s: invalid item type (%d)",
4141			__func__, ITEM_TYPE(item));
4142		ASSERT(0);
4143		return -EIO;
4144	}
4145}
4146
4147STATIC int
4148xlog_recover_items_pass2(
4149	struct xlog                     *log,
4150	struct xlog_recover             *trans,
4151	struct list_head                *buffer_list,
4152	struct list_head                *item_list)
4153{
4154	struct xlog_recover_item	*item;
4155	int				error = 0;
4156
4157	list_for_each_entry(item, item_list, ri_list) {
4158		error = xlog_recover_commit_pass2(log, trans,
4159					  buffer_list, item);
4160		if (error)
4161			return error;
4162	}
4163
4164	return error;
4165}
4166
4167/*
4168 * Perform the transaction.
4169 *
4170 * If the transaction modifies a buffer or inode, do it now.  Otherwise,
4171 * EFIs and EFDs get queued up by adding entries into the AIL for them.
4172 */
4173STATIC int
4174xlog_recover_commit_trans(
4175	struct xlog		*log,
4176	struct xlog_recover	*trans,
4177	int			pass,
4178	struct list_head	*buffer_list)
4179{
4180	int				error = 0;
4181	int				items_queued = 0;
4182	struct xlog_recover_item	*item;
4183	struct xlog_recover_item	*next;
4184	LIST_HEAD			(ra_list);
4185	LIST_HEAD			(done_list);
4186
4187	#define XLOG_RECOVER_COMMIT_QUEUE_MAX 100
4188
4189	hlist_del_init(&trans->r_list);
4190
4191	error = xlog_recover_reorder_trans(log, trans, pass);
4192	if (error)
4193		return error;
4194
4195	list_for_each_entry_safe(item, next, &trans->r_itemq, ri_list) {
4196		switch (pass) {
4197		case XLOG_RECOVER_PASS1:
4198			error = xlog_recover_commit_pass1(log, trans, item);
4199			break;
4200		case XLOG_RECOVER_PASS2:
4201			xlog_recover_ra_pass2(log, item);
4202			list_move_tail(&item->ri_list, &ra_list);
4203			items_queued++;
4204			if (items_queued >= XLOG_RECOVER_COMMIT_QUEUE_MAX) {
4205				error = xlog_recover_items_pass2(log, trans,
4206						buffer_list, &ra_list);
4207				list_splice_tail_init(&ra_list, &done_list);
4208				items_queued = 0;
4209			}
4210
4211			break;
4212		default:
4213			ASSERT(0);
4214		}
4215
4216		if (error)
4217			goto out;
4218	}
4219
4220out:
4221	if (!list_empty(&ra_list)) {
4222		if (!error)
4223			error = xlog_recover_items_pass2(log, trans,
4224					buffer_list, &ra_list);
4225		list_splice_tail_init(&ra_list, &done_list);
4226	}
4227
4228	if (!list_empty(&done_list))
4229		list_splice_init(&done_list, &trans->r_itemq);
4230
4231	return error;
4232}
4233
4234STATIC void
4235xlog_recover_add_item(
4236	struct list_head	*head)
4237{
4238	xlog_recover_item_t	*item;
4239
4240	item = kmem_zalloc(sizeof(xlog_recover_item_t), KM_SLEEP);
4241	INIT_LIST_HEAD(&item->ri_list);
4242	list_add_tail(&item->ri_list, head);
4243}
4244
4245STATIC int
4246xlog_recover_add_to_cont_trans(
4247	struct xlog		*log,
4248	struct xlog_recover	*trans,
4249	char			*dp,
4250	int			len)
4251{
4252	xlog_recover_item_t	*item;
4253	char			*ptr, *old_ptr;
4254	int			old_len;
4255
4256	/*
4257	 * If the transaction is empty, the header was split across this and the
4258	 * previous record. Copy the rest of the header.
4259	 */
4260	if (list_empty(&trans->r_itemq)) {
4261		ASSERT(len <= sizeof(struct xfs_trans_header));
4262		if (len > sizeof(struct xfs_trans_header)) {
4263			xfs_warn(log->l_mp, "%s: bad header length", __func__);
4264			return -EIO;
4265		}
4266
4267		xlog_recover_add_item(&trans->r_itemq);
4268		ptr = (char *)&trans->r_theader +
4269				sizeof(struct xfs_trans_header) - len;
4270		memcpy(ptr, dp, len);
4271		return 0;
4272	}
4273
4274	/* take the tail entry */
4275	item = list_entry(trans->r_itemq.prev, xlog_recover_item_t, ri_list);
4276
4277	old_ptr = item->ri_buf[item->ri_cnt-1].i_addr;
4278	old_len = item->ri_buf[item->ri_cnt-1].i_len;
4279
4280	ptr = kmem_realloc(old_ptr, len + old_len, KM_SLEEP);
4281	memcpy(&ptr[old_len], dp, len);
4282	item->ri_buf[item->ri_cnt-1].i_len += len;
4283	item->ri_buf[item->ri_cnt-1].i_addr = ptr;
4284	trace_xfs_log_recover_item_add_cont(log, trans, item, 0);
4285	return 0;
4286}
4287
4288/*
4289 * The next region to add is the start of a new region.  It could be
4290 * a whole region or it could be the first part of a new region.  Because
4291 * of this, the assumption here is that the type and size fields of all
4292 * format structures fit into the first 32 bits of the structure.
4293 *
4294 * This works because all regions must be 32 bit aligned.  Therefore, we
4295 * either have both fields or we have neither field.  In the case we have
4296 * neither field, the data part of the region is zero length.  We only have
4297 * a log_op_header and can throw away the header since a new one will appear
4298 * later.  If we have at least 4 bytes, then we can determine how many regions
4299 * will appear in the current log item.
4300 */
4301STATIC int
4302xlog_recover_add_to_trans(
4303	struct xlog		*log,
4304	struct xlog_recover	*trans,
4305	char			*dp,
4306	int			len)
4307{
4308	struct xfs_inode_log_format	*in_f;			/* any will do */
4309	xlog_recover_item_t	*item;
4310	char			*ptr;
4311
4312	if (!len)
4313		return 0;
4314	if (list_empty(&trans->r_itemq)) {
4315		/* we need to catch log corruptions here */
4316		if (*(uint *)dp != XFS_TRANS_HEADER_MAGIC) {
4317			xfs_warn(log->l_mp, "%s: bad header magic number",
4318				__func__);
4319			ASSERT(0);
4320			return -EIO;
4321		}
4322
4323		if (len > sizeof(struct xfs_trans_header)) {
4324			xfs_warn(log->l_mp, "%s: bad header length", __func__);
4325			ASSERT(0);
4326			return -EIO;
4327		}
4328
4329		/*
4330		 * The transaction header can be arbitrarily split across op
4331		 * records. If we don't have the whole thing here, copy what we
4332		 * do have and handle the rest in the next record.
4333		 */
4334		if (len == sizeof(struct xfs_trans_header))
4335			xlog_recover_add_item(&trans->r_itemq);
4336		memcpy(&trans->r_theader, dp, len);
4337		return 0;
4338	}
4339
4340	ptr = kmem_alloc(len, KM_SLEEP);
4341	memcpy(ptr, dp, len);
4342	in_f = (struct xfs_inode_log_format *)ptr;
4343
4344	/* take the tail entry */
4345	item = list_entry(trans->r_itemq.prev, xlog_recover_item_t, ri_list);
4346	if (item->ri_total != 0 &&
4347	     item->ri_total == item->ri_cnt) {
4348		/* tail item is in use, get a new one */
4349		xlog_recover_add_item(&trans->r_itemq);
4350		item = list_entry(trans->r_itemq.prev,
4351					xlog_recover_item_t, ri_list);
4352	}
4353
4354	if (item->ri_total == 0) {		/* first region to be added */
4355		if (in_f->ilf_size == 0 ||
4356		    in_f->ilf_size > XLOG_MAX_REGIONS_IN_ITEM) {
4357			xfs_warn(log->l_mp,
4358		"bad number of regions (%d) in inode log format",
4359				  in_f->ilf_size);
4360			ASSERT(0);
4361			kmem_free(ptr);
4362			return -EIO;
4363		}
4364
4365		item->ri_total = in_f->ilf_size;
4366		item->ri_buf =
4367			kmem_zalloc(item->ri_total * sizeof(xfs_log_iovec_t),
4368				    KM_SLEEP);
4369	}
4370	ASSERT(item->ri_total > item->ri_cnt);
4371	/* Description region is ri_buf[0] */
4372	item->ri_buf[item->ri_cnt].i_addr = ptr;
4373	item->ri_buf[item->ri_cnt].i_len  = len;
4374	item->ri_cnt++;
4375	trace_xfs_log_recover_item_add(log, trans, item, 0);
4376	return 0;
4377}
4378
4379/*
4380 * Free up any resources allocated by the transaction
4381 *
4382 * Remember that EFIs, EFDs, and IUNLINKs are handled later.
4383 */
4384STATIC void
4385xlog_recover_free_trans(
4386	struct xlog_recover	*trans)
4387{
4388	xlog_recover_item_t	*item, *n;
4389	int			i;
4390
4391	hlist_del_init(&trans->r_list);
4392
4393	list_for_each_entry_safe(item, n, &trans->r_itemq, ri_list) {
4394		/* Free the regions in the item. */
4395		list_del(&item->ri_list);
4396		for (i = 0; i < item->ri_cnt; i++)
4397			kmem_free(item->ri_buf[i].i_addr);
4398		/* Free the item itself */
4399		kmem_free(item->ri_buf);
4400		kmem_free(item);
4401	}
4402	/* Free the transaction recover structure */
4403	kmem_free(trans);
4404}
4405
4406/*
4407 * On error or completion, trans is freed.
4408 */
4409STATIC int
4410xlog_recovery_process_trans(
4411	struct xlog		*log,
4412	struct xlog_recover	*trans,
4413	char			*dp,
4414	unsigned int		len,
4415	unsigned int		flags,
4416	int			pass,
4417	struct list_head	*buffer_list)
4418{
4419	int			error = 0;
4420	bool			freeit = false;
4421
4422	/* mask off ophdr transaction container flags */
4423	flags &= ~XLOG_END_TRANS;
4424	if (flags & XLOG_WAS_CONT_TRANS)
4425		flags &= ~XLOG_CONTINUE_TRANS;
4426
4427	/*
4428	 * Callees must not free the trans structure. We'll decide if we need to
4429	 * free it or not based on the operation being done and it's result.
4430	 */
4431	switch (flags) {
4432	/* expected flag values */
4433	case 0:
4434	case XLOG_CONTINUE_TRANS:
4435		error = xlog_recover_add_to_trans(log, trans, dp, len);
4436		break;
4437	case XLOG_WAS_CONT_TRANS:
4438		error = xlog_recover_add_to_cont_trans(log, trans, dp, len);
4439		break;
4440	case XLOG_COMMIT_TRANS:
4441		error = xlog_recover_commit_trans(log, trans, pass,
4442						  buffer_list);
4443		/* success or fail, we are now done with this transaction. */
4444		freeit = true;
4445		break;
4446
4447	/* unexpected flag values */
4448	case XLOG_UNMOUNT_TRANS:
4449		/* just skip trans */
4450		xfs_warn(log->l_mp, "%s: Unmount LR", __func__);
4451		freeit = true;
4452		break;
4453	case XLOG_START_TRANS:
4454	default:
4455		xfs_warn(log->l_mp, "%s: bad flag 0x%x", __func__, flags);
4456		ASSERT(0);
4457		error = -EIO;
4458		break;
4459	}
4460	if (error || freeit)
4461		xlog_recover_free_trans(trans);
4462	return error;
4463}
4464
4465/*
4466 * Lookup the transaction recovery structure associated with the ID in the
4467 * current ophdr. If the transaction doesn't exist and the start flag is set in
4468 * the ophdr, then allocate a new transaction for future ID matches to find.
4469 * Either way, return what we found during the lookup - an existing transaction
4470 * or nothing.
4471 */
4472STATIC struct xlog_recover *
4473xlog_recover_ophdr_to_trans(
4474	struct hlist_head	rhash[],
4475	struct xlog_rec_header	*rhead,
4476	struct xlog_op_header	*ohead)
4477{
4478	struct xlog_recover	*trans;
4479	xlog_tid_t		tid;
4480	struct hlist_head	*rhp;
4481
4482	tid = be32_to_cpu(ohead->oh_tid);
4483	rhp = &rhash[XLOG_RHASH(tid)];
4484	hlist_for_each_entry(trans, rhp, r_list) {
4485		if (trans->r_log_tid == tid)
4486			return trans;
4487	}
4488
4489	/*
4490	 * skip over non-start transaction headers - we could be
4491	 * processing slack space before the next transaction starts
4492	 */
4493	if (!(ohead->oh_flags & XLOG_START_TRANS))
4494		return NULL;
4495
4496	ASSERT(be32_to_cpu(ohead->oh_len) == 0);
4497
4498	/*
4499	 * This is a new transaction so allocate a new recovery container to
4500	 * hold the recovery ops that will follow.
4501	 */
4502	trans = kmem_zalloc(sizeof(struct xlog_recover), KM_SLEEP);
4503	trans->r_log_tid = tid;
4504	trans->r_lsn = be64_to_cpu(rhead->h_lsn);
4505	INIT_LIST_HEAD(&trans->r_itemq);
4506	INIT_HLIST_NODE(&trans->r_list);
4507	hlist_add_head(&trans->r_list, rhp);
4508
4509	/*
4510	 * Nothing more to do for this ophdr. Items to be added to this new
4511	 * transaction will be in subsequent ophdr containers.
4512	 */
4513	return NULL;
4514}
4515
4516STATIC int
4517xlog_recover_process_ophdr(
4518	struct xlog		*log,
4519	struct hlist_head	rhash[],
4520	struct xlog_rec_header	*rhead,
4521	struct xlog_op_header	*ohead,
4522	char			*dp,
4523	char			*end,
4524	int			pass,
4525	struct list_head	*buffer_list)
4526{
4527	struct xlog_recover	*trans;
4528	unsigned int		len;
4529	int			error;
4530
4531	/* Do we understand who wrote this op? */
4532	if (ohead->oh_clientid != XFS_TRANSACTION &&
4533	    ohead->oh_clientid != XFS_LOG) {
4534		xfs_warn(log->l_mp, "%s: bad clientid 0x%x",
4535			__func__, ohead->oh_clientid);
4536		ASSERT(0);
4537		return -EIO;
4538	}
4539
4540	/*
4541	 * Check the ophdr contains all the data it is supposed to contain.
4542	 */
4543	len = be32_to_cpu(ohead->oh_len);
4544	if (dp + len > end) {
4545		xfs_warn(log->l_mp, "%s: bad length 0x%x", __func__, len);
4546		WARN_ON(1);
4547		return -EIO;
4548	}
4549
4550	trans = xlog_recover_ophdr_to_trans(rhash, rhead, ohead);
4551	if (!trans) {
4552		/* nothing to do, so skip over this ophdr */
4553		return 0;
4554	}
4555
4556	/*
4557	 * The recovered buffer queue is drained only once we know that all
4558	 * recovery items for the current LSN have been processed. This is
4559	 * required because:
4560	 *
4561	 * - Buffer write submission updates the metadata LSN of the buffer.
4562	 * - Log recovery skips items with a metadata LSN >= the current LSN of
4563	 *   the recovery item.
4564	 * - Separate recovery items against the same metadata buffer can share
4565	 *   a current LSN. I.e., consider that the LSN of a recovery item is
4566	 *   defined as the starting LSN of the first record in which its
4567	 *   transaction appears, that a record can hold multiple transactions,
4568	 *   and/or that a transaction can span multiple records.
4569	 *
4570	 * In other words, we are allowed to submit a buffer from log recovery
4571	 * once per current LSN. Otherwise, we may incorrectly skip recovery
4572	 * items and cause corruption.
4573	 *
4574	 * We don't know up front whether buffers are updated multiple times per
4575	 * LSN. Therefore, track the current LSN of each commit log record as it
4576	 * is processed and drain the queue when it changes. Use commit records
4577	 * because they are ordered correctly by the logging code.
4578	 */
4579	if (log->l_recovery_lsn != trans->r_lsn &&
4580	    ohead->oh_flags & XLOG_COMMIT_TRANS) {
4581		error = xfs_buf_delwri_submit(buffer_list);
4582		if (error)
4583			return error;
4584		log->l_recovery_lsn = trans->r_lsn;
4585	}
4586
4587	return xlog_recovery_process_trans(log, trans, dp, len,
4588					   ohead->oh_flags, pass, buffer_list);
4589}
4590
4591/*
4592 * There are two valid states of the r_state field.  0 indicates that the
4593 * transaction structure is in a normal state.  We have either seen the
4594 * start of the transaction or the last operation we added was not a partial
4595 * operation.  If the last operation we added to the transaction was a
4596 * partial operation, we need to mark r_state with XLOG_WAS_CONT_TRANS.
4597 *
4598 * NOTE: skip LRs with 0 data length.
4599 */
4600STATIC int
4601xlog_recover_process_data(
4602	struct xlog		*log,
4603	struct hlist_head	rhash[],
4604	struct xlog_rec_header	*rhead,
4605	char			*dp,
4606	int			pass,
4607	struct list_head	*buffer_list)
4608{
4609	struct xlog_op_header	*ohead;
4610	char			*end;
4611	int			num_logops;
4612	int			error;
4613
4614	end = dp + be32_to_cpu(rhead->h_len);
4615	num_logops = be32_to_cpu(rhead->h_num_logops);
4616
4617	/* check the log format matches our own - else we can't recover */
4618	if (xlog_header_check_recover(log->l_mp, rhead))
4619		return -EIO;
4620
4621	trace_xfs_log_recover_record(log, rhead, pass);
4622	while ((dp < end) && num_logops) {
4623
4624		ohead = (struct xlog_op_header *)dp;
4625		dp += sizeof(*ohead);
4626		ASSERT(dp <= end);
4627
4628		/* errors will abort recovery */
4629		error = xlog_recover_process_ophdr(log, rhash, rhead, ohead,
4630						   dp, end, pass, buffer_list);
4631		if (error)
4632			return error;
4633
4634		dp += be32_to_cpu(ohead->oh_len);
4635		num_logops--;
4636	}
4637	return 0;
4638}
4639
4640/* Recover the EFI if necessary. */
4641STATIC int
4642xlog_recover_process_efi(
4643	struct xfs_mount		*mp,
4644	struct xfs_ail			*ailp,
4645	struct xfs_log_item		*lip)
4646{
4647	struct xfs_efi_log_item		*efip;
4648	int				error;
4649
4650	/*
4651	 * Skip EFIs that we've already processed.
4652	 */
4653	efip = container_of(lip, struct xfs_efi_log_item, efi_item);
4654	if (test_bit(XFS_EFI_RECOVERED, &efip->efi_flags))
4655		return 0;
4656
4657	spin_unlock(&ailp->ail_lock);
4658	error = xfs_efi_recover(mp, efip);
4659	spin_lock(&ailp->ail_lock);
4660
4661	return error;
4662}
4663
4664/* Release the EFI since we're cancelling everything. */
4665STATIC void
4666xlog_recover_cancel_efi(
4667	struct xfs_mount		*mp,
4668	struct xfs_ail			*ailp,
4669	struct xfs_log_item		*lip)
4670{
4671	struct xfs_efi_log_item		*efip;
4672
4673	efip = container_of(lip, struct xfs_efi_log_item, efi_item);
4674
4675	spin_unlock(&ailp->ail_lock);
4676	xfs_efi_release(efip);
4677	spin_lock(&ailp->ail_lock);
4678}
4679
4680/* Recover the RUI if necessary. */
4681STATIC int
4682xlog_recover_process_rui(
4683	struct xfs_mount		*mp,
4684	struct xfs_ail			*ailp,
4685	struct xfs_log_item		*lip)
4686{
4687	struct xfs_rui_log_item		*ruip;
4688	int				error;
4689
4690	/*
4691	 * Skip RUIs that we've already processed.
4692	 */
4693	ruip = container_of(lip, struct xfs_rui_log_item, rui_item);
4694	if (test_bit(XFS_RUI_RECOVERED, &ruip->rui_flags))
4695		return 0;
4696
4697	spin_unlock(&ailp->ail_lock);
4698	error = xfs_rui_recover(mp, ruip);
4699	spin_lock(&ailp->ail_lock);
4700
4701	return error;
4702}
4703
4704/* Release the RUI since we're cancelling everything. */
4705STATIC void
4706xlog_recover_cancel_rui(
4707	struct xfs_mount		*mp,
4708	struct xfs_ail			*ailp,
4709	struct xfs_log_item		*lip)
4710{
4711	struct xfs_rui_log_item		*ruip;
4712
4713	ruip = container_of(lip, struct xfs_rui_log_item, rui_item);
4714
4715	spin_unlock(&ailp->ail_lock);
4716	xfs_rui_release(ruip);
4717	spin_lock(&ailp->ail_lock);
4718}
4719
4720/* Recover the CUI if necessary. */
4721STATIC int
4722xlog_recover_process_cui(
4723	struct xfs_mount		*mp,
4724	struct xfs_ail			*ailp,
4725	struct xfs_log_item		*lip,
4726	struct xfs_defer_ops		*dfops)
4727{
4728	struct xfs_cui_log_item		*cuip;
4729	int				error;
4730
4731	/*
4732	 * Skip CUIs that we've already processed.
4733	 */
4734	cuip = container_of(lip, struct xfs_cui_log_item, cui_item);
4735	if (test_bit(XFS_CUI_RECOVERED, &cuip->cui_flags))
4736		return 0;
4737
4738	spin_unlock(&ailp->ail_lock);
4739	error = xfs_cui_recover(mp, cuip, dfops);
4740	spin_lock(&ailp->ail_lock);
4741
4742	return error;
4743}
4744
4745/* Release the CUI since we're cancelling everything. */
4746STATIC void
4747xlog_recover_cancel_cui(
4748	struct xfs_mount		*mp,
4749	struct xfs_ail			*ailp,
4750	struct xfs_log_item		*lip)
4751{
4752	struct xfs_cui_log_item		*cuip;
4753
4754	cuip = container_of(lip, struct xfs_cui_log_item, cui_item);
4755
4756	spin_unlock(&ailp->ail_lock);
4757	xfs_cui_release(cuip);
4758	spin_lock(&ailp->ail_lock);
4759}
4760
4761/* Recover the BUI if necessary. */
4762STATIC int
4763xlog_recover_process_bui(
4764	struct xfs_mount		*mp,
4765	struct xfs_ail			*ailp,
4766	struct xfs_log_item		*lip,
4767	struct xfs_defer_ops		*dfops)
4768{
4769	struct xfs_bui_log_item		*buip;
4770	int				error;
4771
4772	/*
4773	 * Skip BUIs that we've already processed.
4774	 */
4775	buip = container_of(lip, struct xfs_bui_log_item, bui_item);
4776	if (test_bit(XFS_BUI_RECOVERED, &buip->bui_flags))
4777		return 0;
4778
4779	spin_unlock(&ailp->ail_lock);
4780	error = xfs_bui_recover(mp, buip, dfops);
4781	spin_lock(&ailp->ail_lock);
4782
4783	return error;
4784}
4785
4786/* Release the BUI since we're cancelling everything. */
4787STATIC void
4788xlog_recover_cancel_bui(
4789	struct xfs_mount		*mp,
4790	struct xfs_ail			*ailp,
4791	struct xfs_log_item		*lip)
4792{
4793	struct xfs_bui_log_item		*buip;
4794
4795	buip = container_of(lip, struct xfs_bui_log_item, bui_item);
4796
4797	spin_unlock(&ailp->ail_lock);
4798	xfs_bui_release(buip);
4799	spin_lock(&ailp->ail_lock);
4800}
4801
4802/* Is this log item a deferred action intent? */
4803static inline bool xlog_item_is_intent(struct xfs_log_item *lip)
4804{
4805	switch (lip->li_type) {
4806	case XFS_LI_EFI:
4807	case XFS_LI_RUI:
4808	case XFS_LI_CUI:
4809	case XFS_LI_BUI:
4810		return true;
4811	default:
4812		return false;
4813	}
4814}
4815
4816/* Take all the collected deferred ops and finish them in order. */
4817static int
4818xlog_finish_defer_ops(
4819	struct xfs_mount	*mp,
4820	struct xfs_defer_ops	*dfops)
4821{
4822	struct xfs_trans	*tp;
4823	int64_t			freeblks;
4824	uint			resblks;
4825	int			error;
4826
4827	/*
4828	 * We're finishing the defer_ops that accumulated as a result of
4829	 * recovering unfinished intent items during log recovery.  We
4830	 * reserve an itruncate transaction because it is the largest
4831	 * permanent transaction type.  Since we're the only user of the fs
4832	 * right now, take 93% (15/16) of the available free blocks.  Use
4833	 * weird math to avoid a 64-bit division.
4834	 */
4835	freeblks = percpu_counter_sum(&mp->m_fdblocks);
4836	if (freeblks <= 0)
4837		return -ENOSPC;
4838	resblks = min_t(int64_t, UINT_MAX, freeblks);
4839	resblks = (resblks * 15) >> 4;
4840	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, resblks,
4841			0, XFS_TRANS_RESERVE, &tp);
4842	if (error)
4843		return error;
4844
4845	error = xfs_defer_finish(&tp, dfops);
4846	if (error)
4847		goto out_cancel;
4848
4849	return xfs_trans_commit(tp);
4850
4851out_cancel:
4852	xfs_trans_cancel(tp);
4853	return error;
4854}
4855
4856/*
4857 * When this is called, all of the log intent items which did not have
4858 * corresponding log done items should be in the AIL.  What we do now
4859 * is update the data structures associated with each one.
4860 *
4861 * Since we process the log intent items in normal transactions, they
4862 * will be removed at some point after the commit.  This prevents us
4863 * from just walking down the list processing each one.  We'll use a
4864 * flag in the intent item to skip those that we've already processed
4865 * and use the AIL iteration mechanism's generation count to try to
4866 * speed this up at least a bit.
4867 *
4868 * When we start, we know that the intents are the only things in the
4869 * AIL.  As we process them, however, other items are added to the
4870 * AIL.
4871 */
4872STATIC int
4873xlog_recover_process_intents(
4874	struct xlog		*log)
4875{
4876	struct xfs_defer_ops	dfops;
4877	struct xfs_ail_cursor	cur;
4878	struct xfs_log_item	*lip;
4879	struct xfs_ail		*ailp;
4880	xfs_fsblock_t		firstfsb;
4881	int			error = 0;
4882#if defined(DEBUG) || defined(XFS_WARN)
 
4883	xfs_lsn_t		last_lsn;
4884#endif
4885
4886	ailp = log->l_ailp;
4887	spin_lock(&ailp->ail_lock);
4888	lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
4889#if defined(DEBUG) || defined(XFS_WARN)
4890	last_lsn = xlog_assign_lsn(log->l_curr_cycle, log->l_curr_block);
4891#endif
4892	xfs_defer_init(&dfops, &firstfsb);
4893	while (lip != NULL) {
4894		/*
4895		 * We're done when we see something other than an intent.
4896		 * There should be no intents left in the AIL now.
4897		 */
4898		if (!xlog_item_is_intent(lip)) {
4899#ifdef DEBUG
4900			for (; lip; lip = xfs_trans_ail_cursor_next(ailp, &cur))
4901				ASSERT(!xlog_item_is_intent(lip));
4902#endif
4903			break;
4904		}
4905
4906		/*
4907		 * We should never see a redo item with a LSN higher than
4908		 * the last transaction we found in the log at the start
4909		 * of recovery.
4910		 */
4911		ASSERT(XFS_LSN_CMP(last_lsn, lip->li_lsn) >= 0);
4912
4913		/*
4914		 * NOTE: If your intent processing routine can create more
4915		 * deferred ops, you /must/ attach them to the dfops in this
4916		 * routine or else those subsequent intents will get
4917		 * replayed in the wrong order!
4918		 */
4919		switch (lip->li_type) {
4920		case XFS_LI_EFI:
4921			error = xlog_recover_process_efi(log->l_mp, ailp, lip);
4922			break;
4923		case XFS_LI_RUI:
4924			error = xlog_recover_process_rui(log->l_mp, ailp, lip);
4925			break;
4926		case XFS_LI_CUI:
4927			error = xlog_recover_process_cui(log->l_mp, ailp, lip,
4928					&dfops);
4929			break;
4930		case XFS_LI_BUI:
4931			error = xlog_recover_process_bui(log->l_mp, ailp, lip,
4932					&dfops);
4933			break;
4934		}
4935		if (error)
4936			goto out;
4937		lip = xfs_trans_ail_cursor_next(ailp, &cur);
4938	}
4939out:
4940	xfs_trans_ail_cursor_done(&cur);
4941	spin_unlock(&ailp->ail_lock);
4942	if (error)
4943		xfs_defer_cancel(&dfops);
4944	else
4945		error = xlog_finish_defer_ops(log->l_mp, &dfops);
4946
4947	return error;
4948}
4949
4950/*
4951 * A cancel occurs when the mount has failed and we're bailing out.
4952 * Release all pending log intent items so they don't pin the AIL.
4953 */
4954STATIC int
4955xlog_recover_cancel_intents(
4956	struct xlog		*log)
4957{
4958	struct xfs_log_item	*lip;
4959	int			error = 0;
4960	struct xfs_ail_cursor	cur;
4961	struct xfs_ail		*ailp;
4962
4963	ailp = log->l_ailp;
4964	spin_lock(&ailp->ail_lock);
4965	lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
4966	while (lip != NULL) {
4967		/*
4968		 * We're done when we see something other than an intent.
4969		 * There should be no intents left in the AIL now.
4970		 */
4971		if (!xlog_item_is_intent(lip)) {
4972#ifdef DEBUG
4973			for (; lip; lip = xfs_trans_ail_cursor_next(ailp, &cur))
4974				ASSERT(!xlog_item_is_intent(lip));
4975#endif
4976			break;
4977		}
4978
4979		switch (lip->li_type) {
4980		case XFS_LI_EFI:
4981			xlog_recover_cancel_efi(log->l_mp, ailp, lip);
4982			break;
4983		case XFS_LI_RUI:
4984			xlog_recover_cancel_rui(log->l_mp, ailp, lip);
4985			break;
4986		case XFS_LI_CUI:
4987			xlog_recover_cancel_cui(log->l_mp, ailp, lip);
4988			break;
4989		case XFS_LI_BUI:
4990			xlog_recover_cancel_bui(log->l_mp, ailp, lip);
4991			break;
4992		}
4993
4994		lip = xfs_trans_ail_cursor_next(ailp, &cur);
4995	}
4996
4997	xfs_trans_ail_cursor_done(&cur);
4998	spin_unlock(&ailp->ail_lock);
4999	return error;
5000}
5001
5002/*
5003 * This routine performs a transaction to null out a bad inode pointer
5004 * in an agi unlinked inode hash bucket.
5005 */
5006STATIC void
5007xlog_recover_clear_agi_bucket(
5008	xfs_mount_t	*mp,
5009	xfs_agnumber_t	agno,
5010	int		bucket)
5011{
5012	xfs_trans_t	*tp;
5013	xfs_agi_t	*agi;
5014	xfs_buf_t	*agibp;
5015	int		offset;
5016	int		error;
5017
5018	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_clearagi, 0, 0, 0, &tp);
5019	if (error)
5020		goto out_error;
5021
5022	error = xfs_read_agi(mp, tp, agno, &agibp);
5023	if (error)
5024		goto out_abort;
5025
5026	agi = XFS_BUF_TO_AGI(agibp);
5027	agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
5028	offset = offsetof(xfs_agi_t, agi_unlinked) +
5029		 (sizeof(xfs_agino_t) * bucket);
5030	xfs_trans_log_buf(tp, agibp, offset,
5031			  (offset + sizeof(xfs_agino_t) - 1));
5032
5033	error = xfs_trans_commit(tp);
5034	if (error)
5035		goto out_error;
5036	return;
5037
5038out_abort:
5039	xfs_trans_cancel(tp);
5040out_error:
5041	xfs_warn(mp, "%s: failed to clear agi %d. Continuing.", __func__, agno);
5042	return;
5043}
5044
5045STATIC xfs_agino_t
5046xlog_recover_process_one_iunlink(
5047	struct xfs_mount		*mp,
5048	xfs_agnumber_t			agno,
5049	xfs_agino_t			agino,
5050	int				bucket)
5051{
5052	struct xfs_buf			*ibp;
5053	struct xfs_dinode		*dip;
5054	struct xfs_inode		*ip;
5055	xfs_ino_t			ino;
5056	int				error;
5057
5058	ino = XFS_AGINO_TO_INO(mp, agno, agino);
5059	error = xfs_iget(mp, NULL, ino, 0, 0, &ip);
5060	if (error)
5061		goto fail;
5062
5063	/*
5064	 * Get the on disk inode to find the next inode in the bucket.
5065	 */
5066	error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &ibp, 0, 0);
5067	if (error)
5068		goto fail_iput;
5069
5070	xfs_iflags_clear(ip, XFS_IRECOVERY);
5071	ASSERT(VFS_I(ip)->i_nlink == 0);
5072	ASSERT(VFS_I(ip)->i_mode != 0);
5073
5074	/* setup for the next pass */
5075	agino = be32_to_cpu(dip->di_next_unlinked);
5076	xfs_buf_relse(ibp);
5077
5078	/*
5079	 * Prevent any DMAPI event from being sent when the reference on
5080	 * the inode is dropped.
5081	 */
5082	ip->i_d.di_dmevmask = 0;
5083
5084	IRELE(ip);
5085	return agino;
5086
5087 fail_iput:
5088	IRELE(ip);
5089 fail:
5090	/*
5091	 * We can't read in the inode this bucket points to, or this inode
5092	 * is messed up.  Just ditch this bucket of inodes.  We will lose
5093	 * some inodes and space, but at least we won't hang.
5094	 *
5095	 * Call xlog_recover_clear_agi_bucket() to perform a transaction to
5096	 * clear the inode pointer in the bucket.
5097	 */
5098	xlog_recover_clear_agi_bucket(mp, agno, bucket);
5099	return NULLAGINO;
5100}
5101
5102/*
5103 * xlog_iunlink_recover
5104 *
5105 * This is called during recovery to process any inodes which
5106 * we unlinked but not freed when the system crashed.  These
5107 * inodes will be on the lists in the AGI blocks.  What we do
5108 * here is scan all the AGIs and fully truncate and free any
5109 * inodes found on the lists.  Each inode is removed from the
5110 * lists when it has been fully truncated and is freed.  The
5111 * freeing of the inode and its removal from the list must be
5112 * atomic.
5113 */
5114STATIC void
5115xlog_recover_process_iunlinks(
5116	struct xlog	*log)
5117{
5118	xfs_mount_t	*mp;
5119	xfs_agnumber_t	agno;
5120	xfs_agi_t	*agi;
5121	xfs_buf_t	*agibp;
5122	xfs_agino_t	agino;
5123	int		bucket;
5124	int		error;
 
5125
5126	mp = log->l_mp;
5127
 
 
 
 
 
 
5128	for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
5129		/*
5130		 * Find the agi for this ag.
5131		 */
5132		error = xfs_read_agi(mp, NULL, agno, &agibp);
5133		if (error) {
5134			/*
5135			 * AGI is b0rked. Don't process it.
5136			 *
5137			 * We should probably mark the filesystem as corrupt
5138			 * after we've recovered all the ag's we can....
5139			 */
5140			continue;
5141		}
5142		/*
5143		 * Unlock the buffer so that it can be acquired in the normal
5144		 * course of the transaction to truncate and free each inode.
5145		 * Because we are not racing with anyone else here for the AGI
5146		 * buffer, we don't even need to hold it locked to read the
5147		 * initial unlinked bucket entries out of the buffer. We keep
5148		 * buffer reference though, so that it stays pinned in memory
5149		 * while we need the buffer.
5150		 */
5151		agi = XFS_BUF_TO_AGI(agibp);
5152		xfs_buf_unlock(agibp);
5153
5154		for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++) {
5155			agino = be32_to_cpu(agi->agi_unlinked[bucket]);
5156			while (agino != NULLAGINO) {
5157				agino = xlog_recover_process_one_iunlink(mp,
5158							agno, agino, bucket);
5159			}
5160		}
5161		xfs_buf_rele(agibp);
5162	}
 
 
5163}
5164
5165STATIC int
5166xlog_unpack_data(
5167	struct xlog_rec_header	*rhead,
5168	char			*dp,
5169	struct xlog		*log)
5170{
5171	int			i, j, k;
5172
5173	for (i = 0; i < BTOBB(be32_to_cpu(rhead->h_len)) &&
5174		  i < (XLOG_HEADER_CYCLE_SIZE / BBSIZE); i++) {
5175		*(__be32 *)dp = *(__be32 *)&rhead->h_cycle_data[i];
5176		dp += BBSIZE;
5177	}
5178
5179	if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
5180		xlog_in_core_2_t *xhdr = (xlog_in_core_2_t *)rhead;
5181		for ( ; i < BTOBB(be32_to_cpu(rhead->h_len)); i++) {
5182			j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
5183			k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
5184			*(__be32 *)dp = xhdr[j].hic_xheader.xh_cycle_data[k];
5185			dp += BBSIZE;
5186		}
5187	}
5188
5189	return 0;
5190}
5191
5192/*
5193 * CRC check, unpack and process a log record.
5194 */
5195STATIC int
5196xlog_recover_process(
5197	struct xlog		*log,
5198	struct hlist_head	rhash[],
5199	struct xlog_rec_header	*rhead,
5200	char			*dp,
5201	int			pass,
5202	struct list_head	*buffer_list)
5203{
5204	int			error;
5205	__le32			old_crc = rhead->h_crc;
5206	__le32			crc;
5207
5208
5209	crc = xlog_cksum(log, rhead, dp, be32_to_cpu(rhead->h_len));
5210
5211	/*
5212	 * Nothing else to do if this is a CRC verification pass. Just return
5213	 * if this a record with a non-zero crc. Unfortunately, mkfs always
5214	 * sets old_crc to 0 so we must consider this valid even on v5 supers.
5215	 * Otherwise, return EFSBADCRC on failure so the callers up the stack
5216	 * know precisely what failed.
5217	 */
5218	if (pass == XLOG_RECOVER_CRCPASS) {
5219		if (old_crc && crc != old_crc)
5220			return -EFSBADCRC;
5221		return 0;
5222	}
5223
5224	/*
5225	 * We're in the normal recovery path. Issue a warning if and only if the
5226	 * CRC in the header is non-zero. This is an advisory warning and the
5227	 * zero CRC check prevents warnings from being emitted when upgrading
5228	 * the kernel from one that does not add CRCs by default.
5229	 */
5230	if (crc != old_crc) {
5231		if (old_crc || xfs_sb_version_hascrc(&log->l_mp->m_sb)) {
5232			xfs_alert(log->l_mp,
5233		"log record CRC mismatch: found 0x%x, expected 0x%x.",
5234					le32_to_cpu(old_crc),
5235					le32_to_cpu(crc));
5236			xfs_hex_dump(dp, 32);
5237		}
5238
5239		/*
5240		 * If the filesystem is CRC enabled, this mismatch becomes a
5241		 * fatal log corruption failure.
5242		 */
5243		if (xfs_sb_version_hascrc(&log->l_mp->m_sb))
5244			return -EFSCORRUPTED;
5245	}
5246
5247	error = xlog_unpack_data(rhead, dp, log);
5248	if (error)
5249		return error;
5250
5251	return xlog_recover_process_data(log, rhash, rhead, dp, pass,
5252					 buffer_list);
5253}
5254
5255STATIC int
5256xlog_valid_rec_header(
5257	struct xlog		*log,
5258	struct xlog_rec_header	*rhead,
5259	xfs_daddr_t		blkno)
5260{
5261	int			hlen;
5262
5263	if (unlikely(rhead->h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM))) {
5264		XFS_ERROR_REPORT("xlog_valid_rec_header(1)",
5265				XFS_ERRLEVEL_LOW, log->l_mp);
5266		return -EFSCORRUPTED;
5267	}
5268	if (unlikely(
5269	    (!rhead->h_version ||
5270	    (be32_to_cpu(rhead->h_version) & (~XLOG_VERSION_OKBITS))))) {
5271		xfs_warn(log->l_mp, "%s: unrecognised log version (%d).",
5272			__func__, be32_to_cpu(rhead->h_version));
5273		return -EIO;
5274	}
5275
5276	/* LR body must have data or it wouldn't have been written */
5277	hlen = be32_to_cpu(rhead->h_len);
5278	if (unlikely( hlen <= 0 || hlen > INT_MAX )) {
5279		XFS_ERROR_REPORT("xlog_valid_rec_header(2)",
5280				XFS_ERRLEVEL_LOW, log->l_mp);
5281		return -EFSCORRUPTED;
5282	}
5283	if (unlikely( blkno > log->l_logBBsize || blkno > INT_MAX )) {
5284		XFS_ERROR_REPORT("xlog_valid_rec_header(3)",
5285				XFS_ERRLEVEL_LOW, log->l_mp);
5286		return -EFSCORRUPTED;
5287	}
5288	return 0;
5289}
5290
5291/*
5292 * Read the log from tail to head and process the log records found.
5293 * Handle the two cases where the tail and head are in the same cycle
5294 * and where the active portion of the log wraps around the end of
5295 * the physical log separately.  The pass parameter is passed through
5296 * to the routines called to process the data and is not looked at
5297 * here.
5298 */
5299STATIC int
5300xlog_do_recovery_pass(
5301	struct xlog		*log,
5302	xfs_daddr_t		head_blk,
5303	xfs_daddr_t		tail_blk,
5304	int			pass,
5305	xfs_daddr_t		*first_bad)	/* out: first bad log rec */
5306{
5307	xlog_rec_header_t	*rhead;
5308	xfs_daddr_t		blk_no, rblk_no;
5309	xfs_daddr_t		rhead_blk;
5310	char			*offset;
5311	xfs_buf_t		*hbp, *dbp;
5312	int			error = 0, h_size, h_len;
5313	int			error2 = 0;
5314	int			bblks, split_bblks;
5315	int			hblks, split_hblks, wrapped_hblks;
5316	int			i;
5317	struct hlist_head	rhash[XLOG_RHASH_SIZE];
5318	LIST_HEAD		(buffer_list);
5319
5320	ASSERT(head_blk != tail_blk);
5321	blk_no = rhead_blk = tail_blk;
5322
5323	for (i = 0; i < XLOG_RHASH_SIZE; i++)
5324		INIT_HLIST_HEAD(&rhash[i]);
5325
5326	/*
5327	 * Read the header of the tail block and get the iclog buffer size from
5328	 * h_size.  Use this to tell how many sectors make up the log header.
5329	 */
5330	if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
5331		/*
5332		 * When using variable length iclogs, read first sector of
5333		 * iclog header and extract the header size from it.  Get a
5334		 * new hbp that is the correct size.
5335		 */
5336		hbp = xlog_get_bp(log, 1);
5337		if (!hbp)
5338			return -ENOMEM;
5339
5340		error = xlog_bread(log, tail_blk, 1, hbp, &offset);
5341		if (error)
5342			goto bread_err1;
5343
5344		rhead = (xlog_rec_header_t *)offset;
5345		error = xlog_valid_rec_header(log, rhead, tail_blk);
5346		if (error)
5347			goto bread_err1;
5348
5349		/*
5350		 * xfsprogs has a bug where record length is based on lsunit but
5351		 * h_size (iclog size) is hardcoded to 32k. Now that we
5352		 * unconditionally CRC verify the unmount record, this means the
5353		 * log buffer can be too small for the record and cause an
5354		 * overrun.
5355		 *
5356		 * Detect this condition here. Use lsunit for the buffer size as
5357		 * long as this looks like the mkfs case. Otherwise, return an
5358		 * error to avoid a buffer overrun.
5359		 */
5360		h_size = be32_to_cpu(rhead->h_size);
5361		h_len = be32_to_cpu(rhead->h_len);
5362		if (h_len > h_size) {
5363			if (h_len <= log->l_mp->m_logbsize &&
5364			    be32_to_cpu(rhead->h_num_logops) == 1) {
5365				xfs_warn(log->l_mp,
5366		"invalid iclog size (%d bytes), using lsunit (%d bytes)",
5367					 h_size, log->l_mp->m_logbsize);
5368				h_size = log->l_mp->m_logbsize;
5369			} else
5370				return -EFSCORRUPTED;
5371		}
5372
5373		if ((be32_to_cpu(rhead->h_version) & XLOG_VERSION_2) &&
5374		    (h_size > XLOG_HEADER_CYCLE_SIZE)) {
5375			hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
5376			if (h_size % XLOG_HEADER_CYCLE_SIZE)
5377				hblks++;
5378			xlog_put_bp(hbp);
5379			hbp = xlog_get_bp(log, hblks);
5380		} else {
5381			hblks = 1;
5382		}
5383	} else {
5384		ASSERT(log->l_sectBBsize == 1);
5385		hblks = 1;
5386		hbp = xlog_get_bp(log, 1);
5387		h_size = XLOG_BIG_RECORD_BSIZE;
5388	}
5389
5390	if (!hbp)
5391		return -ENOMEM;
5392	dbp = xlog_get_bp(log, BTOBB(h_size));
5393	if (!dbp) {
5394		xlog_put_bp(hbp);
5395		return -ENOMEM;
5396	}
5397
5398	memset(rhash, 0, sizeof(rhash));
 
5399	if (tail_blk > head_blk) {
5400		/*
5401		 * Perform recovery around the end of the physical log.
5402		 * When the head is not on the same cycle number as the tail,
5403		 * we can't do a sequential recovery.
5404		 */
5405		while (blk_no < log->l_logBBsize) {
5406			/*
5407			 * Check for header wrapping around physical end-of-log
5408			 */
5409			offset = hbp->b_addr;
5410			split_hblks = 0;
5411			wrapped_hblks = 0;
5412			if (blk_no + hblks <= log->l_logBBsize) {
5413				/* Read header in one read */
5414				error = xlog_bread(log, blk_no, hblks, hbp,
5415						   &offset);
5416				if (error)
5417					goto bread_err2;
5418			} else {
5419				/* This LR is split across physical log end */
5420				if (blk_no != log->l_logBBsize) {
5421					/* some data before physical log end */
5422					ASSERT(blk_no <= INT_MAX);
5423					split_hblks = log->l_logBBsize - (int)blk_no;
5424					ASSERT(split_hblks > 0);
5425					error = xlog_bread(log, blk_no,
5426							   split_hblks, hbp,
5427							   &offset);
5428					if (error)
5429						goto bread_err2;
5430				}
5431
5432				/*
5433				 * Note: this black magic still works with
5434				 * large sector sizes (non-512) only because:
5435				 * - we increased the buffer size originally
5436				 *   by 1 sector giving us enough extra space
5437				 *   for the second read;
5438				 * - the log start is guaranteed to be sector
5439				 *   aligned;
5440				 * - we read the log end (LR header start)
5441				 *   _first_, then the log start (LR header end)
5442				 *   - order is important.
5443				 */
5444				wrapped_hblks = hblks - split_hblks;
5445				error = xlog_bread_offset(log, 0,
5446						wrapped_hblks, hbp,
5447						offset + BBTOB(split_hblks));
5448				if (error)
5449					goto bread_err2;
5450			}
5451			rhead = (xlog_rec_header_t *)offset;
5452			error = xlog_valid_rec_header(log, rhead,
5453						split_hblks ? blk_no : 0);
5454			if (error)
5455				goto bread_err2;
5456
5457			bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
5458			blk_no += hblks;
5459
5460			/*
5461			 * Read the log record data in multiple reads if it
5462			 * wraps around the end of the log. Note that if the
5463			 * header already wrapped, blk_no could point past the
5464			 * end of the log. The record data is contiguous in
5465			 * that case.
5466			 */
5467			if (blk_no + bblks <= log->l_logBBsize ||
5468			    blk_no >= log->l_logBBsize) {
5469				/* mod blk_no in case the header wrapped and
5470				 * pushed it beyond the end of the log */
5471				rblk_no = do_mod(blk_no, log->l_logBBsize);
5472				error = xlog_bread(log, rblk_no, bblks, dbp,
5473						   &offset);
5474				if (error)
5475					goto bread_err2;
5476			} else {
5477				/* This log record is split across the
5478				 * physical end of log */
5479				offset = dbp->b_addr;
5480				split_bblks = 0;
5481				if (blk_no != log->l_logBBsize) {
5482					/* some data is before the physical
5483					 * end of log */
5484					ASSERT(!wrapped_hblks);
5485					ASSERT(blk_no <= INT_MAX);
5486					split_bblks =
5487						log->l_logBBsize - (int)blk_no;
5488					ASSERT(split_bblks > 0);
5489					error = xlog_bread(log, blk_no,
5490							split_bblks, dbp,
5491							&offset);
5492					if (error)
5493						goto bread_err2;
5494				}
5495
5496				/*
5497				 * Note: this black magic still works with
5498				 * large sector sizes (non-512) only because:
5499				 * - we increased the buffer size originally
5500				 *   by 1 sector giving us enough extra space
5501				 *   for the second read;
5502				 * - the log start is guaranteed to be sector
5503				 *   aligned;
5504				 * - we read the log end (LR header start)
5505				 *   _first_, then the log start (LR header end)
5506				 *   - order is important.
5507				 */
5508				error = xlog_bread_offset(log, 0,
5509						bblks - split_bblks, dbp,
5510						offset + BBTOB(split_bblks));
5511				if (error)
5512					goto bread_err2;
5513			}
5514
5515			error = xlog_recover_process(log, rhash, rhead, offset,
5516						     pass, &buffer_list);
5517			if (error)
5518				goto bread_err2;
5519
5520			blk_no += bblks;
5521			rhead_blk = blk_no;
5522		}
5523
5524		ASSERT(blk_no >= log->l_logBBsize);
5525		blk_no -= log->l_logBBsize;
5526		rhead_blk = blk_no;
5527	}
5528
5529	/* read first part of physical log */
5530	while (blk_no < head_blk) {
5531		error = xlog_bread(log, blk_no, hblks, hbp, &offset);
5532		if (error)
5533			goto bread_err2;
5534
5535		rhead = (xlog_rec_header_t *)offset;
5536		error = xlog_valid_rec_header(log, rhead, blk_no);
5537		if (error)
5538			goto bread_err2;
5539
5540		/* blocks in data section */
5541		bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
5542		error = xlog_bread(log, blk_no+hblks, bblks, dbp,
5543				   &offset);
5544		if (error)
5545			goto bread_err2;
5546
5547		error = xlog_recover_process(log, rhash, rhead, offset, pass,
5548					     &buffer_list);
5549		if (error)
5550			goto bread_err2;
5551
5552		blk_no += bblks + hblks;
5553		rhead_blk = blk_no;
5554	}
5555
5556 bread_err2:
5557	xlog_put_bp(dbp);
5558 bread_err1:
5559	xlog_put_bp(hbp);
5560
5561	/*
5562	 * Submit buffers that have been added from the last record processed,
5563	 * regardless of error status.
5564	 */
5565	if (!list_empty(&buffer_list))
5566		error2 = xfs_buf_delwri_submit(&buffer_list);
5567
5568	if (error && first_bad)
5569		*first_bad = rhead_blk;
5570
5571	/*
5572	 * Transactions are freed at commit time but transactions without commit
5573	 * records on disk are never committed. Free any that may be left in the
5574	 * hash table.
5575	 */
5576	for (i = 0; i < XLOG_RHASH_SIZE; i++) {
5577		struct hlist_node	*tmp;
5578		struct xlog_recover	*trans;
5579
5580		hlist_for_each_entry_safe(trans, tmp, &rhash[i], r_list)
5581			xlog_recover_free_trans(trans);
5582	}
5583
5584	return error ? error : error2;
5585}
5586
5587/*
5588 * Do the recovery of the log.  We actually do this in two phases.
5589 * The two passes are necessary in order to implement the function
5590 * of cancelling a record written into the log.  The first pass
5591 * determines those things which have been cancelled, and the
5592 * second pass replays log items normally except for those which
5593 * have been cancelled.  The handling of the replay and cancellations
5594 * takes place in the log item type specific routines.
5595 *
5596 * The table of items which have cancel records in the log is allocated
5597 * and freed at this level, since only here do we know when all of
5598 * the log recovery has been completed.
5599 */
5600STATIC int
5601xlog_do_log_recovery(
5602	struct xlog	*log,
5603	xfs_daddr_t	head_blk,
5604	xfs_daddr_t	tail_blk)
5605{
5606	int		error, i;
5607
5608	ASSERT(head_blk != tail_blk);
5609
5610	/*
5611	 * First do a pass to find all of the cancelled buf log items.
5612	 * Store them in the buf_cancel_table for use in the second pass.
5613	 */
5614	log->l_buf_cancel_table = kmem_zalloc(XLOG_BC_TABLE_SIZE *
5615						 sizeof(struct list_head),
5616						 KM_SLEEP);
5617	for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
5618		INIT_LIST_HEAD(&log->l_buf_cancel_table[i]);
5619
5620	error = xlog_do_recovery_pass(log, head_blk, tail_blk,
5621				      XLOG_RECOVER_PASS1, NULL);
5622	if (error != 0) {
5623		kmem_free(log->l_buf_cancel_table);
5624		log->l_buf_cancel_table = NULL;
5625		return error;
5626	}
5627	/*
5628	 * Then do a second pass to actually recover the items in the log.
5629	 * When it is complete free the table of buf cancel items.
5630	 */
5631	error = xlog_do_recovery_pass(log, head_blk, tail_blk,
5632				      XLOG_RECOVER_PASS2, NULL);
5633#ifdef DEBUG
5634	if (!error) {
5635		int	i;
5636
5637		for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
5638			ASSERT(list_empty(&log->l_buf_cancel_table[i]));
5639	}
5640#endif	/* DEBUG */
5641
5642	kmem_free(log->l_buf_cancel_table);
5643	log->l_buf_cancel_table = NULL;
5644
5645	return error;
5646}
5647
5648/*
5649 * Do the actual recovery
5650 */
5651STATIC int
5652xlog_do_recover(
5653	struct xlog	*log,
5654	xfs_daddr_t	head_blk,
5655	xfs_daddr_t	tail_blk)
5656{
5657	struct xfs_mount *mp = log->l_mp;
5658	int		error;
5659	xfs_buf_t	*bp;
5660	xfs_sb_t	*sbp;
5661
5662	trace_xfs_log_recover(log, head_blk, tail_blk);
5663
5664	/*
5665	 * First replay the images in the log.
5666	 */
5667	error = xlog_do_log_recovery(log, head_blk, tail_blk);
5668	if (error)
5669		return error;
5670
5671	/*
5672	 * If IO errors happened during recovery, bail out.
5673	 */
5674	if (XFS_FORCED_SHUTDOWN(mp)) {
5675		return -EIO;
5676	}
5677
5678	/*
5679	 * We now update the tail_lsn since much of the recovery has completed
5680	 * and there may be space available to use.  If there were no extent
5681	 * or iunlinks, we can free up the entire log and set the tail_lsn to
5682	 * be the last_sync_lsn.  This was set in xlog_find_tail to be the
5683	 * lsn of the last known good LR on disk.  If there are extent frees
5684	 * or iunlinks they will have some entries in the AIL; so we look at
5685	 * the AIL to determine how to set the tail_lsn.
5686	 */
5687	xlog_assign_tail_lsn(mp);
5688
5689	/*
5690	 * Now that we've finished replaying all buffer and inode
5691	 * updates, re-read in the superblock and reverify it.
5692	 */
5693	bp = xfs_getsb(mp, 0);
5694	bp->b_flags &= ~(XBF_DONE | XBF_ASYNC);
5695	ASSERT(!(bp->b_flags & XBF_WRITE));
5696	bp->b_flags |= XBF_READ;
5697	bp->b_ops = &xfs_sb_buf_ops;
5698
5699	error = xfs_buf_submit_wait(bp);
5700	if (error) {
5701		if (!XFS_FORCED_SHUTDOWN(mp)) {
5702			xfs_buf_ioerror_alert(bp, __func__);
5703			ASSERT(0);
5704		}
5705		xfs_buf_relse(bp);
5706		return error;
5707	}
5708
5709	/* Convert superblock from on-disk format */
5710	sbp = &mp->m_sb;
5711	xfs_sb_from_disk(sbp, XFS_BUF_TO_SBP(bp));
5712	xfs_buf_relse(bp);
5713
5714	/* re-initialise in-core superblock and geometry structures */
5715	xfs_reinit_percpu_counters(mp);
5716	error = xfs_initialize_perag(mp, sbp->sb_agcount, &mp->m_maxagi);
5717	if (error) {
5718		xfs_warn(mp, "Failed post-recovery per-ag init: %d", error);
5719		return error;
5720	}
5721	mp->m_alloc_set_aside = xfs_alloc_set_aside(mp);
5722
5723	xlog_recover_check_summary(log);
5724
5725	/* Normal transactions can now occur */
5726	log->l_flags &= ~XLOG_ACTIVE_RECOVERY;
5727	return 0;
5728}
5729
5730/*
5731 * Perform recovery and re-initialize some log variables in xlog_find_tail.
5732 *
5733 * Return error or zero.
5734 */
5735int
5736xlog_recover(
5737	struct xlog	*log)
5738{
5739	xfs_daddr_t	head_blk, tail_blk;
5740	int		error;
5741
5742	/* find the tail of the log */
5743	error = xlog_find_tail(log, &head_blk, &tail_blk);
5744	if (error)
5745		return error;
5746
5747	/*
5748	 * The superblock was read before the log was available and thus the LSN
5749	 * could not be verified. Check the superblock LSN against the current
5750	 * LSN now that it's known.
5751	 */
5752	if (xfs_sb_version_hascrc(&log->l_mp->m_sb) &&
5753	    !xfs_log_check_lsn(log->l_mp, log->l_mp->m_sb.sb_lsn))
5754		return -EINVAL;
5755
5756	if (tail_blk != head_blk) {
5757		/* There used to be a comment here:
5758		 *
5759		 * disallow recovery on read-only mounts.  note -- mount
5760		 * checks for ENOSPC and turns it into an intelligent
5761		 * error message.
5762		 * ...but this is no longer true.  Now, unless you specify
5763		 * NORECOVERY (in which case this function would never be
5764		 * called), we just go ahead and recover.  We do this all
5765		 * under the vfs layer, so we can get away with it unless
5766		 * the device itself is read-only, in which case we fail.
5767		 */
5768		if ((error = xfs_dev_is_read_only(log->l_mp, "recovery"))) {
5769			return error;
5770		}
5771
5772		/*
5773		 * Version 5 superblock log feature mask validation. We know the
5774		 * log is dirty so check if there are any unknown log features
5775		 * in what we need to recover. If there are unknown features
5776		 * (e.g. unsupported transactions, then simply reject the
5777		 * attempt at recovery before touching anything.
5778		 */
5779		if (XFS_SB_VERSION_NUM(&log->l_mp->m_sb) == XFS_SB_VERSION_5 &&
5780		    xfs_sb_has_incompat_log_feature(&log->l_mp->m_sb,
5781					XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN)) {
5782			xfs_warn(log->l_mp,
5783"Superblock has unknown incompatible log features (0x%x) enabled.",
5784				(log->l_mp->m_sb.sb_features_log_incompat &
5785					XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN));
5786			xfs_warn(log->l_mp,
5787"The log can not be fully and/or safely recovered by this kernel.");
5788			xfs_warn(log->l_mp,
5789"Please recover the log on a kernel that supports the unknown features.");
5790			return -EINVAL;
5791		}
5792
5793		/*
5794		 * Delay log recovery if the debug hook is set. This is debug
5795		 * instrumention to coordinate simulation of I/O failures with
5796		 * log recovery.
5797		 */
5798		if (xfs_globals.log_recovery_delay) {
5799			xfs_notice(log->l_mp,
5800				"Delaying log recovery for %d seconds.",
5801				xfs_globals.log_recovery_delay);
5802			msleep(xfs_globals.log_recovery_delay * 1000);
5803		}
5804
5805		xfs_notice(log->l_mp, "Starting recovery (logdev: %s)",
5806				log->l_mp->m_logname ? log->l_mp->m_logname
5807						     : "internal");
5808
5809		error = xlog_do_recover(log, head_blk, tail_blk);
5810		log->l_flags |= XLOG_RECOVERY_NEEDED;
5811	}
5812	return error;
5813}
5814
5815/*
5816 * In the first part of recovery we replay inodes and buffers and build
5817 * up the list of extent free items which need to be processed.  Here
5818 * we process the extent free items and clean up the on disk unlinked
5819 * inode lists.  This is separated from the first part of recovery so
5820 * that the root and real-time bitmap inodes can be read in from disk in
5821 * between the two stages.  This is necessary so that we can free space
5822 * in the real-time portion of the file system.
5823 */
5824int
5825xlog_recover_finish(
5826	struct xlog	*log)
5827{
5828	/*
5829	 * Now we're ready to do the transactions needed for the
5830	 * rest of recovery.  Start with completing all the extent
5831	 * free intent records and then process the unlinked inode
5832	 * lists.  At this point, we essentially run in normal mode
5833	 * except that we're still performing recovery actions
5834	 * rather than accepting new requests.
5835	 */
5836	if (log->l_flags & XLOG_RECOVERY_NEEDED) {
5837		int	error;
5838		error = xlog_recover_process_intents(log);
5839		if (error) {
5840			xfs_alert(log->l_mp, "Failed to recover intents");
5841			return error;
5842		}
5843
5844		/*
5845		 * Sync the log to get all the intents out of the AIL.
5846		 * This isn't absolutely necessary, but it helps in
5847		 * case the unlink transactions would have problems
5848		 * pushing the intents out of the way.
5849		 */
5850		xfs_log_force(log->l_mp, XFS_LOG_SYNC);
5851
5852		xlog_recover_process_iunlinks(log);
5853
5854		xlog_recover_check_summary(log);
5855
5856		xfs_notice(log->l_mp, "Ending recovery (logdev: %s)",
5857				log->l_mp->m_logname ? log->l_mp->m_logname
5858						     : "internal");
5859		log->l_flags &= ~XLOG_RECOVERY_NEEDED;
5860	} else {
5861		xfs_info(log->l_mp, "Ending clean mount");
5862	}
5863	return 0;
5864}
5865
5866int
5867xlog_recover_cancel(
5868	struct xlog	*log)
5869{
5870	int		error = 0;
5871
5872	if (log->l_flags & XLOG_RECOVERY_NEEDED)
5873		error = xlog_recover_cancel_intents(log);
5874
5875	return error;
5876}
5877
5878#if defined(DEBUG)
5879/*
5880 * Read all of the agf and agi counters and check that they
5881 * are consistent with the superblock counters.
5882 */
5883STATIC void
5884xlog_recover_check_summary(
5885	struct xlog	*log)
5886{
5887	xfs_mount_t	*mp;
5888	xfs_agf_t	*agfp;
5889	xfs_buf_t	*agfbp;
5890	xfs_buf_t	*agibp;
5891	xfs_agnumber_t	agno;
5892	uint64_t	freeblks;
5893	uint64_t	itotal;
5894	uint64_t	ifree;
5895	int		error;
5896
5897	mp = log->l_mp;
5898
5899	freeblks = 0LL;
5900	itotal = 0LL;
5901	ifree = 0LL;
5902	for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
5903		error = xfs_read_agf(mp, NULL, agno, 0, &agfbp);
5904		if (error) {
5905			xfs_alert(mp, "%s agf read failed agno %d error %d",
5906						__func__, agno, error);
5907		} else {
5908			agfp = XFS_BUF_TO_AGF(agfbp);
5909			freeblks += be32_to_cpu(agfp->agf_freeblks) +
5910				    be32_to_cpu(agfp->agf_flcount);
5911			xfs_buf_relse(agfbp);
5912		}
5913
5914		error = xfs_read_agi(mp, NULL, agno, &agibp);
5915		if (error) {
5916			xfs_alert(mp, "%s agi read failed agno %d error %d",
5917						__func__, agno, error);
5918		} else {
5919			struct xfs_agi	*agi = XFS_BUF_TO_AGI(agibp);
5920
5921			itotal += be32_to_cpu(agi->agi_count);
5922			ifree += be32_to_cpu(agi->agi_freecount);
5923			xfs_buf_relse(agibp);
5924		}
5925	}
5926}
5927#endif /* DEBUG */
v4.10.11
   1/*
   2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
   3 * All Rights Reserved.
   4 *
   5 * This program is free software; you can redistribute it and/or
   6 * modify it under the terms of the GNU General Public License as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it would be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write the Free Software Foundation,
  16 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18#include "xfs.h"
  19#include "xfs_fs.h"
  20#include "xfs_shared.h"
  21#include "xfs_format.h"
  22#include "xfs_log_format.h"
  23#include "xfs_trans_resv.h"
  24#include "xfs_bit.h"
  25#include "xfs_sb.h"
  26#include "xfs_mount.h"
 
  27#include "xfs_da_format.h"
  28#include "xfs_da_btree.h"
  29#include "xfs_inode.h"
  30#include "xfs_trans.h"
  31#include "xfs_log.h"
  32#include "xfs_log_priv.h"
  33#include "xfs_log_recover.h"
  34#include "xfs_inode_item.h"
  35#include "xfs_extfree_item.h"
  36#include "xfs_trans_priv.h"
  37#include "xfs_alloc.h"
  38#include "xfs_ialloc.h"
  39#include "xfs_quota.h"
  40#include "xfs_cksum.h"
  41#include "xfs_trace.h"
  42#include "xfs_icache.h"
  43#include "xfs_bmap_btree.h"
  44#include "xfs_error.h"
  45#include "xfs_dir2.h"
  46#include "xfs_rmap_item.h"
  47#include "xfs_buf_item.h"
  48#include "xfs_refcount_item.h"
  49#include "xfs_bmap_item.h"
  50
  51#define BLK_AVG(blk1, blk2)	((blk1+blk2) >> 1)
  52
  53STATIC int
  54xlog_find_zeroed(
  55	struct xlog	*,
  56	xfs_daddr_t	*);
  57STATIC int
  58xlog_clear_stale_blocks(
  59	struct xlog	*,
  60	xfs_lsn_t);
  61#if defined(DEBUG)
  62STATIC void
  63xlog_recover_check_summary(
  64	struct xlog *);
  65#else
  66#define	xlog_recover_check_summary(log)
  67#endif
  68STATIC int
  69xlog_do_recovery_pass(
  70        struct xlog *, xfs_daddr_t, xfs_daddr_t, int, xfs_daddr_t *);
  71
  72/*
  73 * This structure is used during recovery to record the buf log items which
  74 * have been canceled and should not be replayed.
  75 */
  76struct xfs_buf_cancel {
  77	xfs_daddr_t		bc_blkno;
  78	uint			bc_len;
  79	int			bc_refcount;
  80	struct list_head	bc_list;
  81};
  82
  83/*
  84 * Sector aligned buffer routines for buffer create/read/write/access
  85 */
  86
  87/*
  88 * Verify the given count of basic blocks is valid number of blocks
  89 * to specify for an operation involving the given XFS log buffer.
  90 * Returns nonzero if the count is valid, 0 otherwise.
  91 */
  92
  93static inline int
  94xlog_buf_bbcount_valid(
  95	struct xlog	*log,
 
  96	int		bbcount)
  97{
  98	return bbcount > 0 && bbcount <= log->l_logBBsize;
 
 
 
 
  99}
 100
 101/*
 102 * Allocate a buffer to hold log data.  The buffer needs to be able
 103 * to map to a range of nbblks basic blocks at any valid (basic
 104 * block) offset within the log.
 105 */
 106STATIC xfs_buf_t *
 107xlog_get_bp(
 108	struct xlog	*log,
 109	int		nbblks)
 110{
 111	struct xfs_buf	*bp;
 112
 113	if (!xlog_buf_bbcount_valid(log, nbblks)) {
 
 
 
 
 114		xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer",
 115			nbblks);
 116		XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
 117		return NULL;
 118	}
 119
 120	/*
 121	 * We do log I/O in units of log sectors (a power-of-2
 122	 * multiple of the basic block size), so we round up the
 123	 * requested size to accommodate the basic blocks required
 124	 * for complete log sectors.
 125	 *
 126	 * In addition, the buffer may be used for a non-sector-
 127	 * aligned block offset, in which case an I/O of the
 128	 * requested size could extend beyond the end of the
 129	 * buffer.  If the requested size is only 1 basic block it
 130	 * will never straddle a sector boundary, so this won't be
 131	 * an issue.  Nor will this be a problem if the log I/O is
 132	 * done in basic blocks (sector size 1).  But otherwise we
 133	 * extend the buffer by one extra log sector to ensure
 134	 * there's space to accommodate this possibility.
 135	 */
 136	if (nbblks > 1 && log->l_sectBBsize > 1)
 137		nbblks += log->l_sectBBsize;
 138	nbblks = round_up(nbblks, log->l_sectBBsize);
 139
 140	bp = xfs_buf_get_uncached(log->l_mp->m_logdev_targp, nbblks, 0);
 141	if (bp)
 142		xfs_buf_unlock(bp);
 143	return bp;
 144}
 145
 146STATIC void
 147xlog_put_bp(
 148	xfs_buf_t	*bp)
 149{
 150	xfs_buf_free(bp);
 151}
 152
 153/*
 154 * Return the address of the start of the given block number's data
 155 * in a log buffer.  The buffer covers a log sector-aligned region.
 156 */
 157STATIC char *
 158xlog_align(
 159	struct xlog	*log,
 160	xfs_daddr_t	blk_no,
 161	int		nbblks,
 162	struct xfs_buf	*bp)
 163{
 164	xfs_daddr_t	offset = blk_no & ((xfs_daddr_t)log->l_sectBBsize - 1);
 165
 166	ASSERT(offset + nbblks <= bp->b_length);
 167	return bp->b_addr + BBTOB(offset);
 168}
 169
 170
 171/*
 172 * nbblks should be uint, but oh well.  Just want to catch that 32-bit length.
 173 */
 174STATIC int
 175xlog_bread_noalign(
 176	struct xlog	*log,
 177	xfs_daddr_t	blk_no,
 178	int		nbblks,
 179	struct xfs_buf	*bp)
 180{
 181	int		error;
 182
 183	if (!xlog_buf_bbcount_valid(log, nbblks)) {
 184		xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer",
 185			nbblks);
 
 186		XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
 187		return -EFSCORRUPTED;
 188	}
 189
 190	blk_no = round_down(blk_no, log->l_sectBBsize);
 191	nbblks = round_up(nbblks, log->l_sectBBsize);
 192
 193	ASSERT(nbblks > 0);
 194	ASSERT(nbblks <= bp->b_length);
 195
 196	XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no);
 197	bp->b_flags |= XBF_READ;
 198	bp->b_io_length = nbblks;
 199	bp->b_error = 0;
 200
 201	error = xfs_buf_submit_wait(bp);
 202	if (error && !XFS_FORCED_SHUTDOWN(log->l_mp))
 203		xfs_buf_ioerror_alert(bp, __func__);
 204	return error;
 205}
 206
 207STATIC int
 208xlog_bread(
 209	struct xlog	*log,
 210	xfs_daddr_t	blk_no,
 211	int		nbblks,
 212	struct xfs_buf	*bp,
 213	char		**offset)
 214{
 215	int		error;
 216
 217	error = xlog_bread_noalign(log, blk_no, nbblks, bp);
 218	if (error)
 219		return error;
 220
 221	*offset = xlog_align(log, blk_no, nbblks, bp);
 222	return 0;
 223}
 224
 225/*
 226 * Read at an offset into the buffer. Returns with the buffer in it's original
 227 * state regardless of the result of the read.
 228 */
 229STATIC int
 230xlog_bread_offset(
 231	struct xlog	*log,
 232	xfs_daddr_t	blk_no,		/* block to read from */
 233	int		nbblks,		/* blocks to read */
 234	struct xfs_buf	*bp,
 235	char		*offset)
 236{
 237	char		*orig_offset = bp->b_addr;
 238	int		orig_len = BBTOB(bp->b_length);
 239	int		error, error2;
 240
 241	error = xfs_buf_associate_memory(bp, offset, BBTOB(nbblks));
 242	if (error)
 243		return error;
 244
 245	error = xlog_bread_noalign(log, blk_no, nbblks, bp);
 246
 247	/* must reset buffer pointer even on error */
 248	error2 = xfs_buf_associate_memory(bp, orig_offset, orig_len);
 249	if (error)
 250		return error;
 251	return error2;
 252}
 253
 254/*
 255 * Write out the buffer at the given block for the given number of blocks.
 256 * The buffer is kept locked across the write and is returned locked.
 257 * This can only be used for synchronous log writes.
 258 */
 259STATIC int
 260xlog_bwrite(
 261	struct xlog	*log,
 262	xfs_daddr_t	blk_no,
 263	int		nbblks,
 264	struct xfs_buf	*bp)
 265{
 266	int		error;
 267
 268	if (!xlog_buf_bbcount_valid(log, nbblks)) {
 269		xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer",
 270			nbblks);
 
 271		XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
 272		return -EFSCORRUPTED;
 273	}
 274
 275	blk_no = round_down(blk_no, log->l_sectBBsize);
 276	nbblks = round_up(nbblks, log->l_sectBBsize);
 277
 278	ASSERT(nbblks > 0);
 279	ASSERT(nbblks <= bp->b_length);
 280
 281	XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no);
 282	xfs_buf_hold(bp);
 283	xfs_buf_lock(bp);
 284	bp->b_io_length = nbblks;
 285	bp->b_error = 0;
 286
 287	error = xfs_bwrite(bp);
 288	if (error)
 289		xfs_buf_ioerror_alert(bp, __func__);
 290	xfs_buf_relse(bp);
 291	return error;
 292}
 293
 294#ifdef DEBUG
 295/*
 296 * dump debug superblock and log record information
 297 */
 298STATIC void
 299xlog_header_check_dump(
 300	xfs_mount_t		*mp,
 301	xlog_rec_header_t	*head)
 302{
 303	xfs_debug(mp, "%s:  SB : uuid = %pU, fmt = %d",
 304		__func__, &mp->m_sb.sb_uuid, XLOG_FMT);
 305	xfs_debug(mp, "    log : uuid = %pU, fmt = %d",
 306		&head->h_fs_uuid, be32_to_cpu(head->h_fmt));
 307}
 308#else
 309#define xlog_header_check_dump(mp, head)
 310#endif
 311
 312/*
 313 * check log record header for recovery
 314 */
 315STATIC int
 316xlog_header_check_recover(
 317	xfs_mount_t		*mp,
 318	xlog_rec_header_t	*head)
 319{
 320	ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM));
 321
 322	/*
 323	 * IRIX doesn't write the h_fmt field and leaves it zeroed
 324	 * (XLOG_FMT_UNKNOWN). This stops us from trying to recover
 325	 * a dirty log created in IRIX.
 326	 */
 327	if (unlikely(head->h_fmt != cpu_to_be32(XLOG_FMT))) {
 328		xfs_warn(mp,
 329	"dirty log written in incompatible format - can't recover");
 330		xlog_header_check_dump(mp, head);
 331		XFS_ERROR_REPORT("xlog_header_check_recover(1)",
 332				 XFS_ERRLEVEL_HIGH, mp);
 333		return -EFSCORRUPTED;
 334	} else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) {
 335		xfs_warn(mp,
 336	"dirty log entry has mismatched uuid - can't recover");
 337		xlog_header_check_dump(mp, head);
 338		XFS_ERROR_REPORT("xlog_header_check_recover(2)",
 339				 XFS_ERRLEVEL_HIGH, mp);
 340		return -EFSCORRUPTED;
 341	}
 342	return 0;
 343}
 344
 345/*
 346 * read the head block of the log and check the header
 347 */
 348STATIC int
 349xlog_header_check_mount(
 350	xfs_mount_t		*mp,
 351	xlog_rec_header_t	*head)
 352{
 353	ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM));
 354
 355	if (uuid_is_nil(&head->h_fs_uuid)) {
 356		/*
 357		 * IRIX doesn't write the h_fs_uuid or h_fmt fields. If
 358		 * h_fs_uuid is nil, we assume this log was last mounted
 359		 * by IRIX and continue.
 360		 */
 361		xfs_warn(mp, "nil uuid in log - IRIX style log");
 362	} else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) {
 363		xfs_warn(mp, "log has mismatched uuid - can't recover");
 364		xlog_header_check_dump(mp, head);
 365		XFS_ERROR_REPORT("xlog_header_check_mount",
 366				 XFS_ERRLEVEL_HIGH, mp);
 367		return -EFSCORRUPTED;
 368	}
 369	return 0;
 370}
 371
 372STATIC void
 373xlog_recover_iodone(
 374	struct xfs_buf	*bp)
 375{
 376	if (bp->b_error) {
 377		/*
 378		 * We're not going to bother about retrying
 379		 * this during recovery. One strike!
 380		 */
 381		if (!XFS_FORCED_SHUTDOWN(bp->b_target->bt_mount)) {
 382			xfs_buf_ioerror_alert(bp, __func__);
 383			xfs_force_shutdown(bp->b_target->bt_mount,
 384						SHUTDOWN_META_IO_ERROR);
 385		}
 386	}
 387
 388	/*
 389	 * On v5 supers, a bli could be attached to update the metadata LSN.
 390	 * Clean it up.
 391	 */
 392	if (bp->b_fspriv)
 393		xfs_buf_item_relse(bp);
 394	ASSERT(bp->b_fspriv == NULL);
 395
 396	bp->b_iodone = NULL;
 397	xfs_buf_ioend(bp);
 398}
 399
 400/*
 401 * This routine finds (to an approximation) the first block in the physical
 402 * log which contains the given cycle.  It uses a binary search algorithm.
 403 * Note that the algorithm can not be perfect because the disk will not
 404 * necessarily be perfect.
 405 */
 406STATIC int
 407xlog_find_cycle_start(
 408	struct xlog	*log,
 409	struct xfs_buf	*bp,
 410	xfs_daddr_t	first_blk,
 411	xfs_daddr_t	*last_blk,
 412	uint		cycle)
 413{
 414	char		*offset;
 415	xfs_daddr_t	mid_blk;
 416	xfs_daddr_t	end_blk;
 417	uint		mid_cycle;
 418	int		error;
 419
 420	end_blk = *last_blk;
 421	mid_blk = BLK_AVG(first_blk, end_blk);
 422	while (mid_blk != first_blk && mid_blk != end_blk) {
 423		error = xlog_bread(log, mid_blk, 1, bp, &offset);
 424		if (error)
 425			return error;
 426		mid_cycle = xlog_get_cycle(offset);
 427		if (mid_cycle == cycle)
 428			end_blk = mid_blk;   /* last_half_cycle == mid_cycle */
 429		else
 430			first_blk = mid_blk; /* first_half_cycle == mid_cycle */
 431		mid_blk = BLK_AVG(first_blk, end_blk);
 432	}
 433	ASSERT((mid_blk == first_blk && mid_blk+1 == end_blk) ||
 434	       (mid_blk == end_blk && mid_blk-1 == first_blk));
 435
 436	*last_blk = end_blk;
 437
 438	return 0;
 439}
 440
 441/*
 442 * Check that a range of blocks does not contain stop_on_cycle_no.
 443 * Fill in *new_blk with the block offset where such a block is
 444 * found, or with -1 (an invalid block number) if there is no such
 445 * block in the range.  The scan needs to occur from front to back
 446 * and the pointer into the region must be updated since a later
 447 * routine will need to perform another test.
 448 */
 449STATIC int
 450xlog_find_verify_cycle(
 451	struct xlog	*log,
 452	xfs_daddr_t	start_blk,
 453	int		nbblks,
 454	uint		stop_on_cycle_no,
 455	xfs_daddr_t	*new_blk)
 456{
 457	xfs_daddr_t	i, j;
 458	uint		cycle;
 459	xfs_buf_t	*bp;
 460	xfs_daddr_t	bufblks;
 461	char		*buf = NULL;
 462	int		error = 0;
 463
 464	/*
 465	 * Greedily allocate a buffer big enough to handle the full
 466	 * range of basic blocks we'll be examining.  If that fails,
 467	 * try a smaller size.  We need to be able to read at least
 468	 * a log sector, or we're out of luck.
 469	 */
 470	bufblks = 1 << ffs(nbblks);
 471	while (bufblks > log->l_logBBsize)
 472		bufblks >>= 1;
 473	while (!(bp = xlog_get_bp(log, bufblks))) {
 474		bufblks >>= 1;
 475		if (bufblks < log->l_sectBBsize)
 476			return -ENOMEM;
 477	}
 478
 479	for (i = start_blk; i < start_blk + nbblks; i += bufblks) {
 480		int	bcount;
 481
 482		bcount = min(bufblks, (start_blk + nbblks - i));
 483
 484		error = xlog_bread(log, i, bcount, bp, &buf);
 485		if (error)
 486			goto out;
 487
 488		for (j = 0; j < bcount; j++) {
 489			cycle = xlog_get_cycle(buf);
 490			if (cycle == stop_on_cycle_no) {
 491				*new_blk = i+j;
 492				goto out;
 493			}
 494
 495			buf += BBSIZE;
 496		}
 497	}
 498
 499	*new_blk = -1;
 500
 501out:
 502	xlog_put_bp(bp);
 503	return error;
 504}
 505
 506/*
 507 * Potentially backup over partial log record write.
 508 *
 509 * In the typical case, last_blk is the number of the block directly after
 510 * a good log record.  Therefore, we subtract one to get the block number
 511 * of the last block in the given buffer.  extra_bblks contains the number
 512 * of blocks we would have read on a previous read.  This happens when the
 513 * last log record is split over the end of the physical log.
 514 *
 515 * extra_bblks is the number of blocks potentially verified on a previous
 516 * call to this routine.
 517 */
 518STATIC int
 519xlog_find_verify_log_record(
 520	struct xlog		*log,
 521	xfs_daddr_t		start_blk,
 522	xfs_daddr_t		*last_blk,
 523	int			extra_bblks)
 524{
 525	xfs_daddr_t		i;
 526	xfs_buf_t		*bp;
 527	char			*offset = NULL;
 528	xlog_rec_header_t	*head = NULL;
 529	int			error = 0;
 530	int			smallmem = 0;
 531	int			num_blks = *last_blk - start_blk;
 532	int			xhdrs;
 533
 534	ASSERT(start_blk != 0 || *last_blk != start_blk);
 535
 536	if (!(bp = xlog_get_bp(log, num_blks))) {
 537		if (!(bp = xlog_get_bp(log, 1)))
 538			return -ENOMEM;
 539		smallmem = 1;
 540	} else {
 541		error = xlog_bread(log, start_blk, num_blks, bp, &offset);
 542		if (error)
 543			goto out;
 544		offset += ((num_blks - 1) << BBSHIFT);
 545	}
 546
 547	for (i = (*last_blk) - 1; i >= 0; i--) {
 548		if (i < start_blk) {
 549			/* valid log record not found */
 550			xfs_warn(log->l_mp,
 551		"Log inconsistent (didn't find previous header)");
 552			ASSERT(0);
 553			error = -EIO;
 554			goto out;
 555		}
 556
 557		if (smallmem) {
 558			error = xlog_bread(log, i, 1, bp, &offset);
 559			if (error)
 560				goto out;
 561		}
 562
 563		head = (xlog_rec_header_t *)offset;
 564
 565		if (head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM))
 566			break;
 567
 568		if (!smallmem)
 569			offset -= BBSIZE;
 570	}
 571
 572	/*
 573	 * We hit the beginning of the physical log & still no header.  Return
 574	 * to caller.  If caller can handle a return of -1, then this routine
 575	 * will be called again for the end of the physical log.
 576	 */
 577	if (i == -1) {
 578		error = 1;
 579		goto out;
 580	}
 581
 582	/*
 583	 * We have the final block of the good log (the first block
 584	 * of the log record _before_ the head. So we check the uuid.
 585	 */
 586	if ((error = xlog_header_check_mount(log->l_mp, head)))
 587		goto out;
 588
 589	/*
 590	 * We may have found a log record header before we expected one.
 591	 * last_blk will be the 1st block # with a given cycle #.  We may end
 592	 * up reading an entire log record.  In this case, we don't want to
 593	 * reset last_blk.  Only when last_blk points in the middle of a log
 594	 * record do we update last_blk.
 595	 */
 596	if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
 597		uint	h_size = be32_to_cpu(head->h_size);
 598
 599		xhdrs = h_size / XLOG_HEADER_CYCLE_SIZE;
 600		if (h_size % XLOG_HEADER_CYCLE_SIZE)
 601			xhdrs++;
 602	} else {
 603		xhdrs = 1;
 604	}
 605
 606	if (*last_blk - i + extra_bblks !=
 607	    BTOBB(be32_to_cpu(head->h_len)) + xhdrs)
 608		*last_blk = i;
 609
 610out:
 611	xlog_put_bp(bp);
 612	return error;
 613}
 614
 615/*
 616 * Head is defined to be the point of the log where the next log write
 617 * could go.  This means that incomplete LR writes at the end are
 618 * eliminated when calculating the head.  We aren't guaranteed that previous
 619 * LR have complete transactions.  We only know that a cycle number of
 620 * current cycle number -1 won't be present in the log if we start writing
 621 * from our current block number.
 622 *
 623 * last_blk contains the block number of the first block with a given
 624 * cycle number.
 625 *
 626 * Return: zero if normal, non-zero if error.
 627 */
 628STATIC int
 629xlog_find_head(
 630	struct xlog	*log,
 631	xfs_daddr_t	*return_head_blk)
 632{
 633	xfs_buf_t	*bp;
 634	char		*offset;
 635	xfs_daddr_t	new_blk, first_blk, start_blk, last_blk, head_blk;
 636	int		num_scan_bblks;
 637	uint		first_half_cycle, last_half_cycle;
 638	uint		stop_on_cycle;
 639	int		error, log_bbnum = log->l_logBBsize;
 640
 641	/* Is the end of the log device zeroed? */
 642	error = xlog_find_zeroed(log, &first_blk);
 643	if (error < 0) {
 644		xfs_warn(log->l_mp, "empty log check failed");
 645		return error;
 646	}
 647	if (error == 1) {
 648		*return_head_blk = first_blk;
 649
 650		/* Is the whole lot zeroed? */
 651		if (!first_blk) {
 652			/* Linux XFS shouldn't generate totally zeroed logs -
 653			 * mkfs etc write a dummy unmount record to a fresh
 654			 * log so we can store the uuid in there
 655			 */
 656			xfs_warn(log->l_mp, "totally zeroed log");
 657		}
 658
 659		return 0;
 660	}
 661
 662	first_blk = 0;			/* get cycle # of 1st block */
 663	bp = xlog_get_bp(log, 1);
 664	if (!bp)
 665		return -ENOMEM;
 666
 667	error = xlog_bread(log, 0, 1, bp, &offset);
 668	if (error)
 669		goto bp_err;
 670
 671	first_half_cycle = xlog_get_cycle(offset);
 672
 673	last_blk = head_blk = log_bbnum - 1;	/* get cycle # of last block */
 674	error = xlog_bread(log, last_blk, 1, bp, &offset);
 675	if (error)
 676		goto bp_err;
 677
 678	last_half_cycle = xlog_get_cycle(offset);
 679	ASSERT(last_half_cycle != 0);
 680
 681	/*
 682	 * If the 1st half cycle number is equal to the last half cycle number,
 683	 * then the entire log is stamped with the same cycle number.  In this
 684	 * case, head_blk can't be set to zero (which makes sense).  The below
 685	 * math doesn't work out properly with head_blk equal to zero.  Instead,
 686	 * we set it to log_bbnum which is an invalid block number, but this
 687	 * value makes the math correct.  If head_blk doesn't changed through
 688	 * all the tests below, *head_blk is set to zero at the very end rather
 689	 * than log_bbnum.  In a sense, log_bbnum and zero are the same block
 690	 * in a circular file.
 691	 */
 692	if (first_half_cycle == last_half_cycle) {
 693		/*
 694		 * In this case we believe that the entire log should have
 695		 * cycle number last_half_cycle.  We need to scan backwards
 696		 * from the end verifying that there are no holes still
 697		 * containing last_half_cycle - 1.  If we find such a hole,
 698		 * then the start of that hole will be the new head.  The
 699		 * simple case looks like
 700		 *        x | x ... | x - 1 | x
 701		 * Another case that fits this picture would be
 702		 *        x | x + 1 | x ... | x
 703		 * In this case the head really is somewhere at the end of the
 704		 * log, as one of the latest writes at the beginning was
 705		 * incomplete.
 706		 * One more case is
 707		 *        x | x + 1 | x ... | x - 1 | x
 708		 * This is really the combination of the above two cases, and
 709		 * the head has to end up at the start of the x-1 hole at the
 710		 * end of the log.
 711		 *
 712		 * In the 256k log case, we will read from the beginning to the
 713		 * end of the log and search for cycle numbers equal to x-1.
 714		 * We don't worry about the x+1 blocks that we encounter,
 715		 * because we know that they cannot be the head since the log
 716		 * started with x.
 717		 */
 718		head_blk = log_bbnum;
 719		stop_on_cycle = last_half_cycle - 1;
 720	} else {
 721		/*
 722		 * In this case we want to find the first block with cycle
 723		 * number matching last_half_cycle.  We expect the log to be
 724		 * some variation on
 725		 *        x + 1 ... | x ... | x
 726		 * The first block with cycle number x (last_half_cycle) will
 727		 * be where the new head belongs.  First we do a binary search
 728		 * for the first occurrence of last_half_cycle.  The binary
 729		 * search may not be totally accurate, so then we scan back
 730		 * from there looking for occurrences of last_half_cycle before
 731		 * us.  If that backwards scan wraps around the beginning of
 732		 * the log, then we look for occurrences of last_half_cycle - 1
 733		 * at the end of the log.  The cases we're looking for look
 734		 * like
 735		 *                               v binary search stopped here
 736		 *        x + 1 ... | x | x + 1 | x ... | x
 737		 *                   ^ but we want to locate this spot
 738		 * or
 739		 *        <---------> less than scan distance
 740		 *        x + 1 ... | x ... | x - 1 | x
 741		 *                           ^ we want to locate this spot
 742		 */
 743		stop_on_cycle = last_half_cycle;
 744		if ((error = xlog_find_cycle_start(log, bp, first_blk,
 745						&head_blk, last_half_cycle)))
 746			goto bp_err;
 747	}
 748
 749	/*
 750	 * Now validate the answer.  Scan back some number of maximum possible
 751	 * blocks and make sure each one has the expected cycle number.  The
 752	 * maximum is determined by the total possible amount of buffering
 753	 * in the in-core log.  The following number can be made tighter if
 754	 * we actually look at the block size of the filesystem.
 755	 */
 756	num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log);
 757	if (head_blk >= num_scan_bblks) {
 758		/*
 759		 * We are guaranteed that the entire check can be performed
 760		 * in one buffer.
 761		 */
 762		start_blk = head_blk - num_scan_bblks;
 763		if ((error = xlog_find_verify_cycle(log,
 764						start_blk, num_scan_bblks,
 765						stop_on_cycle, &new_blk)))
 766			goto bp_err;
 767		if (new_blk != -1)
 768			head_blk = new_blk;
 769	} else {		/* need to read 2 parts of log */
 770		/*
 771		 * We are going to scan backwards in the log in two parts.
 772		 * First we scan the physical end of the log.  In this part
 773		 * of the log, we are looking for blocks with cycle number
 774		 * last_half_cycle - 1.
 775		 * If we find one, then we know that the log starts there, as
 776		 * we've found a hole that didn't get written in going around
 777		 * the end of the physical log.  The simple case for this is
 778		 *        x + 1 ... | x ... | x - 1 | x
 779		 *        <---------> less than scan distance
 780		 * If all of the blocks at the end of the log have cycle number
 781		 * last_half_cycle, then we check the blocks at the start of
 782		 * the log looking for occurrences of last_half_cycle.  If we
 783		 * find one, then our current estimate for the location of the
 784		 * first occurrence of last_half_cycle is wrong and we move
 785		 * back to the hole we've found.  This case looks like
 786		 *        x + 1 ... | x | x + 1 | x ...
 787		 *                               ^ binary search stopped here
 788		 * Another case we need to handle that only occurs in 256k
 789		 * logs is
 790		 *        x + 1 ... | x ... | x+1 | x ...
 791		 *                   ^ binary search stops here
 792		 * In a 256k log, the scan at the end of the log will see the
 793		 * x + 1 blocks.  We need to skip past those since that is
 794		 * certainly not the head of the log.  By searching for
 795		 * last_half_cycle-1 we accomplish that.
 796		 */
 797		ASSERT(head_blk <= INT_MAX &&
 798			(xfs_daddr_t) num_scan_bblks >= head_blk);
 799		start_blk = log_bbnum - (num_scan_bblks - head_blk);
 800		if ((error = xlog_find_verify_cycle(log, start_blk,
 801					num_scan_bblks - (int)head_blk,
 802					(stop_on_cycle - 1), &new_blk)))
 803			goto bp_err;
 804		if (new_blk != -1) {
 805			head_blk = new_blk;
 806			goto validate_head;
 807		}
 808
 809		/*
 810		 * Scan beginning of log now.  The last part of the physical
 811		 * log is good.  This scan needs to verify that it doesn't find
 812		 * the last_half_cycle.
 813		 */
 814		start_blk = 0;
 815		ASSERT(head_blk <= INT_MAX);
 816		if ((error = xlog_find_verify_cycle(log,
 817					start_blk, (int)head_blk,
 818					stop_on_cycle, &new_blk)))
 819			goto bp_err;
 820		if (new_blk != -1)
 821			head_blk = new_blk;
 822	}
 823
 824validate_head:
 825	/*
 826	 * Now we need to make sure head_blk is not pointing to a block in
 827	 * the middle of a log record.
 828	 */
 829	num_scan_bblks = XLOG_REC_SHIFT(log);
 830	if (head_blk >= num_scan_bblks) {
 831		start_blk = head_blk - num_scan_bblks; /* don't read head_blk */
 832
 833		/* start ptr at last block ptr before head_blk */
 834		error = xlog_find_verify_log_record(log, start_blk, &head_blk, 0);
 835		if (error == 1)
 836			error = -EIO;
 837		if (error)
 838			goto bp_err;
 839	} else {
 840		start_blk = 0;
 841		ASSERT(head_blk <= INT_MAX);
 842		error = xlog_find_verify_log_record(log, start_blk, &head_blk, 0);
 843		if (error < 0)
 844			goto bp_err;
 845		if (error == 1) {
 846			/* We hit the beginning of the log during our search */
 847			start_blk = log_bbnum - (num_scan_bblks - head_blk);
 848			new_blk = log_bbnum;
 849			ASSERT(start_blk <= INT_MAX &&
 850				(xfs_daddr_t) log_bbnum-start_blk >= 0);
 851			ASSERT(head_blk <= INT_MAX);
 852			error = xlog_find_verify_log_record(log, start_blk,
 853							&new_blk, (int)head_blk);
 854			if (error == 1)
 855				error = -EIO;
 856			if (error)
 857				goto bp_err;
 858			if (new_blk != log_bbnum)
 859				head_blk = new_blk;
 860		} else if (error)
 861			goto bp_err;
 862	}
 863
 864	xlog_put_bp(bp);
 865	if (head_blk == log_bbnum)
 866		*return_head_blk = 0;
 867	else
 868		*return_head_blk = head_blk;
 869	/*
 870	 * When returning here, we have a good block number.  Bad block
 871	 * means that during a previous crash, we didn't have a clean break
 872	 * from cycle number N to cycle number N-1.  In this case, we need
 873	 * to find the first block with cycle number N-1.
 874	 */
 875	return 0;
 876
 877 bp_err:
 878	xlog_put_bp(bp);
 879
 880	if (error)
 881		xfs_warn(log->l_mp, "failed to find log head");
 882	return error;
 883}
 884
 885/*
 886 * Seek backwards in the log for log record headers.
 887 *
 888 * Given a starting log block, walk backwards until we find the provided number
 889 * of records or hit the provided tail block. The return value is the number of
 890 * records encountered or a negative error code. The log block and buffer
 891 * pointer of the last record seen are returned in rblk and rhead respectively.
 892 */
 893STATIC int
 894xlog_rseek_logrec_hdr(
 895	struct xlog		*log,
 896	xfs_daddr_t		head_blk,
 897	xfs_daddr_t		tail_blk,
 898	int			count,
 899	struct xfs_buf		*bp,
 900	xfs_daddr_t		*rblk,
 901	struct xlog_rec_header	**rhead,
 902	bool			*wrapped)
 903{
 904	int			i;
 905	int			error;
 906	int			found = 0;
 907	char			*offset = NULL;
 908	xfs_daddr_t		end_blk;
 909
 910	*wrapped = false;
 911
 912	/*
 913	 * Walk backwards from the head block until we hit the tail or the first
 914	 * block in the log.
 915	 */
 916	end_blk = head_blk > tail_blk ? tail_blk : 0;
 917	for (i = (int) head_blk - 1; i >= end_blk; i--) {
 918		error = xlog_bread(log, i, 1, bp, &offset);
 919		if (error)
 920			goto out_error;
 921
 922		if (*(__be32 *) offset == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
 923			*rblk = i;
 924			*rhead = (struct xlog_rec_header *) offset;
 925			if (++found == count)
 926				break;
 927		}
 928	}
 929
 930	/*
 931	 * If we haven't hit the tail block or the log record header count,
 932	 * start looking again from the end of the physical log. Note that
 933	 * callers can pass head == tail if the tail is not yet known.
 934	 */
 935	if (tail_blk >= head_blk && found != count) {
 936		for (i = log->l_logBBsize - 1; i >= (int) tail_blk; i--) {
 937			error = xlog_bread(log, i, 1, bp, &offset);
 938			if (error)
 939				goto out_error;
 940
 941			if (*(__be32 *)offset ==
 942			    cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
 943				*wrapped = true;
 944				*rblk = i;
 945				*rhead = (struct xlog_rec_header *) offset;
 946				if (++found == count)
 947					break;
 948			}
 949		}
 950	}
 951
 952	return found;
 953
 954out_error:
 955	return error;
 956}
 957
 958/*
 959 * Seek forward in the log for log record headers.
 960 *
 961 * Given head and tail blocks, walk forward from the tail block until we find
 962 * the provided number of records or hit the head block. The return value is the
 963 * number of records encountered or a negative error code. The log block and
 964 * buffer pointer of the last record seen are returned in rblk and rhead
 965 * respectively.
 966 */
 967STATIC int
 968xlog_seek_logrec_hdr(
 969	struct xlog		*log,
 970	xfs_daddr_t		head_blk,
 971	xfs_daddr_t		tail_blk,
 972	int			count,
 973	struct xfs_buf		*bp,
 974	xfs_daddr_t		*rblk,
 975	struct xlog_rec_header	**rhead,
 976	bool			*wrapped)
 977{
 978	int			i;
 979	int			error;
 980	int			found = 0;
 981	char			*offset = NULL;
 982	xfs_daddr_t		end_blk;
 983
 984	*wrapped = false;
 985
 986	/*
 987	 * Walk forward from the tail block until we hit the head or the last
 988	 * block in the log.
 989	 */
 990	end_blk = head_blk > tail_blk ? head_blk : log->l_logBBsize - 1;
 991	for (i = (int) tail_blk; i <= end_blk; i++) {
 992		error = xlog_bread(log, i, 1, bp, &offset);
 993		if (error)
 994			goto out_error;
 995
 996		if (*(__be32 *) offset == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
 997			*rblk = i;
 998			*rhead = (struct xlog_rec_header *) offset;
 999			if (++found == count)
1000				break;
1001		}
1002	}
1003
1004	/*
1005	 * If we haven't hit the head block or the log record header count,
1006	 * start looking again from the start of the physical log.
1007	 */
1008	if (tail_blk > head_blk && found != count) {
1009		for (i = 0; i < (int) head_blk; i++) {
1010			error = xlog_bread(log, i, 1, bp, &offset);
1011			if (error)
1012				goto out_error;
1013
1014			if (*(__be32 *)offset ==
1015			    cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
1016				*wrapped = true;
1017				*rblk = i;
1018				*rhead = (struct xlog_rec_header *) offset;
1019				if (++found == count)
1020					break;
1021			}
1022		}
1023	}
1024
1025	return found;
1026
1027out_error:
1028	return error;
1029}
1030
1031/*
1032 * Check the log tail for torn writes. This is required when torn writes are
1033 * detected at the head and the head had to be walked back to a previous record.
1034 * The tail of the previous record must now be verified to ensure the torn
1035 * writes didn't corrupt the previous tail.
1036 *
1037 * Return an error if CRC verification fails as recovery cannot proceed.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1038 */
1039STATIC int
1040xlog_verify_tail(
1041	struct xlog		*log,
1042	xfs_daddr_t		head_blk,
1043	xfs_daddr_t		tail_blk)
 
1044{
1045	struct xlog_rec_header	*thead;
1046	struct xfs_buf		*bp;
1047	xfs_daddr_t		first_bad;
1048	int			count;
1049	int			error = 0;
1050	bool			wrapped;
1051	xfs_daddr_t		tmp_head;
 
1052
1053	bp = xlog_get_bp(log, 1);
1054	if (!bp)
1055		return -ENOMEM;
1056
1057	/*
1058	 * Seek XLOG_MAX_ICLOGS + 1 records past the current tail record to get
1059	 * a temporary head block that points after the last possible
1060	 * concurrently written record of the tail.
1061	 */
1062	count = xlog_seek_logrec_hdr(log, head_blk, tail_blk,
1063				     XLOG_MAX_ICLOGS + 1, bp, &tmp_head, &thead,
1064				     &wrapped);
1065	if (count < 0) {
1066		error = count;
1067		goto out;
1068	}
 
1069
1070	/*
1071	 * If the call above didn't find XLOG_MAX_ICLOGS + 1 records, we ran
1072	 * into the actual log head. tmp_head points to the start of the record
1073	 * so update it to the actual head block.
 
 
1074	 */
1075	if (count < XLOG_MAX_ICLOGS + 1)
1076		tmp_head = head_blk;
 
 
 
 
 
 
 
 
 
 
 
1077
1078	/*
1079	 * We now have a tail and temporary head block that covers at least
1080	 * XLOG_MAX_ICLOGS records from the tail. We need to verify that these
1081	 * records were completely written. Run a CRC verification pass from
1082	 * tail to head and return the result.
1083	 */
1084	error = xlog_do_recovery_pass(log, tmp_head, tail_blk,
1085				      XLOG_RECOVER_CRCPASS, &first_bad);
 
 
 
1086
 
 
 
 
1087out:
1088	xlog_put_bp(bp);
1089	return error;
1090}
1091
1092/*
1093 * Detect and trim torn writes from the head of the log.
1094 *
1095 * Storage without sector atomicity guarantees can result in torn writes in the
1096 * log in the event of a crash. Our only means to detect this scenario is via
1097 * CRC verification. While we can't always be certain that CRC verification
1098 * failure is due to a torn write vs. an unrelated corruption, we do know that
1099 * only a certain number (XLOG_MAX_ICLOGS) of log records can be written out at
1100 * one time. Therefore, CRC verify up to XLOG_MAX_ICLOGS records at the head of
1101 * the log and treat failures in this range as torn writes as a matter of
1102 * policy. In the event of CRC failure, the head is walked back to the last good
1103 * record in the log and the tail is updated from that record and verified.
1104 */
1105STATIC int
1106xlog_verify_head(
1107	struct xlog		*log,
1108	xfs_daddr_t		*head_blk,	/* in/out: unverified head */
1109	xfs_daddr_t		*tail_blk,	/* out: tail block */
1110	struct xfs_buf		*bp,
1111	xfs_daddr_t		*rhead_blk,	/* start blk of last record */
1112	struct xlog_rec_header	**rhead,	/* ptr to last record */
1113	bool			*wrapped)	/* last rec. wraps phys. log */
1114{
1115	struct xlog_rec_header	*tmp_rhead;
1116	struct xfs_buf		*tmp_bp;
1117	xfs_daddr_t		first_bad;
1118	xfs_daddr_t		tmp_rhead_blk;
1119	int			found;
1120	int			error;
1121	bool			tmp_wrapped;
1122
1123	/*
1124	 * Check the head of the log for torn writes. Search backwards from the
1125	 * head until we hit the tail or the maximum number of log record I/Os
1126	 * that could have been in flight at one time. Use a temporary buffer so
1127	 * we don't trash the rhead/bp pointers from the caller.
1128	 */
1129	tmp_bp = xlog_get_bp(log, 1);
1130	if (!tmp_bp)
1131		return -ENOMEM;
1132	error = xlog_rseek_logrec_hdr(log, *head_blk, *tail_blk,
1133				      XLOG_MAX_ICLOGS, tmp_bp, &tmp_rhead_blk,
1134				      &tmp_rhead, &tmp_wrapped);
1135	xlog_put_bp(tmp_bp);
1136	if (error < 0)
1137		return error;
1138
1139	/*
1140	 * Now run a CRC verification pass over the records starting at the
1141	 * block found above to the current head. If a CRC failure occurs, the
1142	 * log block of the first bad record is saved in first_bad.
1143	 */
1144	error = xlog_do_recovery_pass(log, *head_blk, tmp_rhead_blk,
1145				      XLOG_RECOVER_CRCPASS, &first_bad);
1146	if (error == -EFSBADCRC) {
1147		/*
1148		 * We've hit a potential torn write. Reset the error and warn
1149		 * about it.
1150		 */
1151		error = 0;
1152		xfs_warn(log->l_mp,
1153"Torn write (CRC failure) detected at log block 0x%llx. Truncating head block from 0x%llx.",
1154			 first_bad, *head_blk);
1155
1156		/*
1157		 * Get the header block and buffer pointer for the last good
1158		 * record before the bad record.
1159		 *
1160		 * Note that xlog_find_tail() clears the blocks at the new head
1161		 * (i.e., the records with invalid CRC) if the cycle number
1162		 * matches the the current cycle.
1163		 */
1164		found = xlog_rseek_logrec_hdr(log, first_bad, *tail_blk, 1, bp,
1165					      rhead_blk, rhead, wrapped);
1166		if (found < 0)
1167			return found;
1168		if (found == 0)		/* XXX: right thing to do here? */
1169			return -EIO;
1170
1171		/*
1172		 * Reset the head block to the starting block of the first bad
1173		 * log record and set the tail block based on the last good
1174		 * record.
1175		 *
1176		 * Bail out if the updated head/tail match as this indicates
1177		 * possible corruption outside of the acceptable
1178		 * (XLOG_MAX_ICLOGS) range. This is a job for xfs_repair...
1179		 */
1180		*head_blk = first_bad;
1181		*tail_blk = BLOCK_LSN(be64_to_cpu((*rhead)->h_tail_lsn));
1182		if (*head_blk == *tail_blk) {
1183			ASSERT(0);
1184			return 0;
1185		}
1186
1187		/*
1188		 * Now verify the tail based on the updated head. This is
1189		 * required because the torn writes trimmed from the head could
1190		 * have been written over the tail of a previous record. Return
1191		 * any errors since recovery cannot proceed if the tail is
1192		 * corrupt.
1193		 *
1194		 * XXX: This leaves a gap in truly robust protection from torn
1195		 * writes in the log. If the head is behind the tail, the tail
1196		 * pushes forward to create some space and then a crash occurs
1197		 * causing the writes into the previous record's tail region to
1198		 * tear, log recovery isn't able to recover.
1199		 *
1200		 * How likely is this to occur? If possible, can we do something
1201		 * more intelligent here? Is it safe to push the tail forward if
1202		 * we can determine that the tail is within the range of the
1203		 * torn write (e.g., the kernel can only overwrite the tail if
1204		 * it has actually been pushed forward)? Alternatively, could we
1205		 * somehow prevent this condition at runtime?
1206		 */
1207		error = xlog_verify_tail(log, *head_blk, *tail_blk);
1208	}
 
 
1209
1210	return error;
 
1211}
1212
1213/*
1214 * Check whether the head of the log points to an unmount record. In other
1215 * words, determine whether the log is clean. If so, update the in-core state
1216 * appropriately.
1217 */
1218static int
1219xlog_check_unmount_rec(
1220	struct xlog		*log,
1221	xfs_daddr_t		*head_blk,
1222	xfs_daddr_t		*tail_blk,
1223	struct xlog_rec_header	*rhead,
1224	xfs_daddr_t		rhead_blk,
1225	struct xfs_buf		*bp,
1226	bool			*clean)
1227{
1228	struct xlog_op_header	*op_head;
1229	xfs_daddr_t		umount_data_blk;
1230	xfs_daddr_t		after_umount_blk;
1231	int			hblks;
1232	int			error;
1233	char			*offset;
1234
1235	*clean = false;
1236
1237	/*
1238	 * Look for unmount record. If we find it, then we know there was a
1239	 * clean unmount. Since 'i' could be the last block in the physical
1240	 * log, we convert to a log block before comparing to the head_blk.
1241	 *
1242	 * Save the current tail lsn to use to pass to xlog_clear_stale_blocks()
1243	 * below. We won't want to clear the unmount record if there is one, so
1244	 * we pass the lsn of the unmount record rather than the block after it.
1245	 */
1246	if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
1247		int	h_size = be32_to_cpu(rhead->h_size);
1248		int	h_version = be32_to_cpu(rhead->h_version);
1249
1250		if ((h_version & XLOG_VERSION_2) &&
1251		    (h_size > XLOG_HEADER_CYCLE_SIZE)) {
1252			hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
1253			if (h_size % XLOG_HEADER_CYCLE_SIZE)
1254				hblks++;
1255		} else {
1256			hblks = 1;
1257		}
1258	} else {
1259		hblks = 1;
1260	}
1261	after_umount_blk = rhead_blk + hblks + BTOBB(be32_to_cpu(rhead->h_len));
1262	after_umount_blk = do_mod(after_umount_blk, log->l_logBBsize);
1263	if (*head_blk == after_umount_blk &&
1264	    be32_to_cpu(rhead->h_num_logops) == 1) {
1265		umount_data_blk = rhead_blk + hblks;
1266		umount_data_blk = do_mod(umount_data_blk, log->l_logBBsize);
1267		error = xlog_bread(log, umount_data_blk, 1, bp, &offset);
1268		if (error)
1269			return error;
1270
1271		op_head = (struct xlog_op_header *)offset;
1272		if (op_head->oh_flags & XLOG_UNMOUNT_TRANS) {
1273			/*
1274			 * Set tail and last sync so that newly written log
1275			 * records will point recovery to after the current
1276			 * unmount record.
1277			 */
1278			xlog_assign_atomic_lsn(&log->l_tail_lsn,
1279					log->l_curr_cycle, after_umount_blk);
1280			xlog_assign_atomic_lsn(&log->l_last_sync_lsn,
1281					log->l_curr_cycle, after_umount_blk);
1282			*tail_blk = after_umount_blk;
1283
1284			*clean = true;
1285		}
1286	}
1287
1288	return 0;
1289}
1290
1291static void
1292xlog_set_state(
1293	struct xlog		*log,
1294	xfs_daddr_t		head_blk,
1295	struct xlog_rec_header	*rhead,
1296	xfs_daddr_t		rhead_blk,
1297	bool			bump_cycle)
1298{
1299	/*
1300	 * Reset log values according to the state of the log when we
1301	 * crashed.  In the case where head_blk == 0, we bump curr_cycle
1302	 * one because the next write starts a new cycle rather than
1303	 * continuing the cycle of the last good log record.  At this
1304	 * point we have guaranteed that all partial log records have been
1305	 * accounted for.  Therefore, we know that the last good log record
1306	 * written was complete and ended exactly on the end boundary
1307	 * of the physical log.
1308	 */
1309	log->l_prev_block = rhead_blk;
1310	log->l_curr_block = (int)head_blk;
1311	log->l_curr_cycle = be32_to_cpu(rhead->h_cycle);
1312	if (bump_cycle)
1313		log->l_curr_cycle++;
1314	atomic64_set(&log->l_tail_lsn, be64_to_cpu(rhead->h_tail_lsn));
1315	atomic64_set(&log->l_last_sync_lsn, be64_to_cpu(rhead->h_lsn));
1316	xlog_assign_grant_head(&log->l_reserve_head.grant, log->l_curr_cycle,
1317					BBTOB(log->l_curr_block));
1318	xlog_assign_grant_head(&log->l_write_head.grant, log->l_curr_cycle,
1319					BBTOB(log->l_curr_block));
1320}
1321
1322/*
1323 * Find the sync block number or the tail of the log.
1324 *
1325 * This will be the block number of the last record to have its
1326 * associated buffers synced to disk.  Every log record header has
1327 * a sync lsn embedded in it.  LSNs hold block numbers, so it is easy
1328 * to get a sync block number.  The only concern is to figure out which
1329 * log record header to believe.
1330 *
1331 * The following algorithm uses the log record header with the largest
1332 * lsn.  The entire log record does not need to be valid.  We only care
1333 * that the header is valid.
1334 *
1335 * We could speed up search by using current head_blk buffer, but it is not
1336 * available.
1337 */
1338STATIC int
1339xlog_find_tail(
1340	struct xlog		*log,
1341	xfs_daddr_t		*head_blk,
1342	xfs_daddr_t		*tail_blk)
1343{
1344	xlog_rec_header_t	*rhead;
1345	char			*offset = NULL;
1346	xfs_buf_t		*bp;
1347	int			error;
1348	xfs_daddr_t		rhead_blk;
1349	xfs_lsn_t		tail_lsn;
1350	bool			wrapped = false;
1351	bool			clean = false;
1352
1353	/*
1354	 * Find previous log record
1355	 */
1356	if ((error = xlog_find_head(log, head_blk)))
1357		return error;
1358	ASSERT(*head_blk < INT_MAX);
1359
1360	bp = xlog_get_bp(log, 1);
1361	if (!bp)
1362		return -ENOMEM;
1363	if (*head_blk == 0) {				/* special case */
1364		error = xlog_bread(log, 0, 1, bp, &offset);
1365		if (error)
1366			goto done;
1367
1368		if (xlog_get_cycle(offset) == 0) {
1369			*tail_blk = 0;
1370			/* leave all other log inited values alone */
1371			goto done;
1372		}
1373	}
1374
1375	/*
1376	 * Search backwards through the log looking for the log record header
1377	 * block. This wraps all the way back around to the head so something is
1378	 * seriously wrong if we can't find it.
1379	 */
1380	error = xlog_rseek_logrec_hdr(log, *head_blk, *head_blk, 1, bp,
1381				      &rhead_blk, &rhead, &wrapped);
1382	if (error < 0)
1383		return error;
1384	if (!error) {
1385		xfs_warn(log->l_mp, "%s: couldn't find sync record", __func__);
1386		return -EIO;
1387	}
1388	*tail_blk = BLOCK_LSN(be64_to_cpu(rhead->h_tail_lsn));
1389
1390	/*
1391	 * Set the log state based on the current head record.
1392	 */
1393	xlog_set_state(log, *head_blk, rhead, rhead_blk, wrapped);
1394	tail_lsn = atomic64_read(&log->l_tail_lsn);
1395
1396	/*
1397	 * Look for an unmount record at the head of the log. This sets the log
1398	 * state to determine whether recovery is necessary.
1399	 */
1400	error = xlog_check_unmount_rec(log, head_blk, tail_blk, rhead,
1401				       rhead_blk, bp, &clean);
1402	if (error)
1403		goto done;
1404
1405	/*
1406	 * Verify the log head if the log is not clean (e.g., we have anything
1407	 * but an unmount record at the head). This uses CRC verification to
1408	 * detect and trim torn writes. If discovered, CRC failures are
1409	 * considered torn writes and the log head is trimmed accordingly.
1410	 *
1411	 * Note that we can only run CRC verification when the log is dirty
1412	 * because there's no guarantee that the log data behind an unmount
1413	 * record is compatible with the current architecture.
1414	 */
1415	if (!clean) {
1416		xfs_daddr_t	orig_head = *head_blk;
1417
1418		error = xlog_verify_head(log, head_blk, tail_blk, bp,
1419					 &rhead_blk, &rhead, &wrapped);
1420		if (error)
1421			goto done;
1422
1423		/* update in-core state again if the head changed */
1424		if (*head_blk != orig_head) {
1425			xlog_set_state(log, *head_blk, rhead, rhead_blk,
1426				       wrapped);
1427			tail_lsn = atomic64_read(&log->l_tail_lsn);
1428			error = xlog_check_unmount_rec(log, head_blk, tail_blk,
1429						       rhead, rhead_blk, bp,
1430						       &clean);
1431			if (error)
1432				goto done;
1433		}
1434	}
1435
1436	/*
1437	 * Note that the unmount was clean. If the unmount was not clean, we
1438	 * need to know this to rebuild the superblock counters from the perag
1439	 * headers if we have a filesystem using non-persistent counters.
1440	 */
1441	if (clean)
1442		log->l_mp->m_flags |= XFS_MOUNT_WAS_CLEAN;
1443
1444	/*
1445	 * Make sure that there are no blocks in front of the head
1446	 * with the same cycle number as the head.  This can happen
1447	 * because we allow multiple outstanding log writes concurrently,
1448	 * and the later writes might make it out before earlier ones.
1449	 *
1450	 * We use the lsn from before modifying it so that we'll never
1451	 * overwrite the unmount record after a clean unmount.
1452	 *
1453	 * Do this only if we are going to recover the filesystem
1454	 *
1455	 * NOTE: This used to say "if (!readonly)"
1456	 * However on Linux, we can & do recover a read-only filesystem.
1457	 * We only skip recovery if NORECOVERY is specified on mount,
1458	 * in which case we would not be here.
1459	 *
1460	 * But... if the -device- itself is readonly, just skip this.
1461	 * We can't recover this device anyway, so it won't matter.
1462	 */
1463	if (!xfs_readonly_buftarg(log->l_mp->m_logdev_targp))
1464		error = xlog_clear_stale_blocks(log, tail_lsn);
1465
1466done:
1467	xlog_put_bp(bp);
1468
1469	if (error)
1470		xfs_warn(log->l_mp, "failed to locate log tail");
1471	return error;
1472}
1473
1474/*
1475 * Is the log zeroed at all?
1476 *
1477 * The last binary search should be changed to perform an X block read
1478 * once X becomes small enough.  You can then search linearly through
1479 * the X blocks.  This will cut down on the number of reads we need to do.
1480 *
1481 * If the log is partially zeroed, this routine will pass back the blkno
1482 * of the first block with cycle number 0.  It won't have a complete LR
1483 * preceding it.
1484 *
1485 * Return:
1486 *	0  => the log is completely written to
1487 *	1 => use *blk_no as the first block of the log
1488 *	<0 => error has occurred
1489 */
1490STATIC int
1491xlog_find_zeroed(
1492	struct xlog	*log,
1493	xfs_daddr_t	*blk_no)
1494{
1495	xfs_buf_t	*bp;
1496	char		*offset;
1497	uint	        first_cycle, last_cycle;
1498	xfs_daddr_t	new_blk, last_blk, start_blk;
1499	xfs_daddr_t     num_scan_bblks;
1500	int	        error, log_bbnum = log->l_logBBsize;
1501
1502	*blk_no = 0;
1503
1504	/* check totally zeroed log */
1505	bp = xlog_get_bp(log, 1);
1506	if (!bp)
1507		return -ENOMEM;
1508	error = xlog_bread(log, 0, 1, bp, &offset);
1509	if (error)
1510		goto bp_err;
1511
1512	first_cycle = xlog_get_cycle(offset);
1513	if (first_cycle == 0) {		/* completely zeroed log */
1514		*blk_no = 0;
1515		xlog_put_bp(bp);
1516		return 1;
1517	}
1518
1519	/* check partially zeroed log */
1520	error = xlog_bread(log, log_bbnum-1, 1, bp, &offset);
1521	if (error)
1522		goto bp_err;
1523
1524	last_cycle = xlog_get_cycle(offset);
1525	if (last_cycle != 0) {		/* log completely written to */
1526		xlog_put_bp(bp);
1527		return 0;
1528	} else if (first_cycle != 1) {
1529		/*
1530		 * If the cycle of the last block is zero, the cycle of
1531		 * the first block must be 1. If it's not, maybe we're
1532		 * not looking at a log... Bail out.
1533		 */
1534		xfs_warn(log->l_mp,
1535			"Log inconsistent or not a log (last==0, first!=1)");
1536		error = -EINVAL;
1537		goto bp_err;
1538	}
1539
1540	/* we have a partially zeroed log */
1541	last_blk = log_bbnum-1;
1542	if ((error = xlog_find_cycle_start(log, bp, 0, &last_blk, 0)))
1543		goto bp_err;
1544
1545	/*
1546	 * Validate the answer.  Because there is no way to guarantee that
1547	 * the entire log is made up of log records which are the same size,
1548	 * we scan over the defined maximum blocks.  At this point, the maximum
1549	 * is not chosen to mean anything special.   XXXmiken
1550	 */
1551	num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log);
1552	ASSERT(num_scan_bblks <= INT_MAX);
1553
1554	if (last_blk < num_scan_bblks)
1555		num_scan_bblks = last_blk;
1556	start_blk = last_blk - num_scan_bblks;
1557
1558	/*
1559	 * We search for any instances of cycle number 0 that occur before
1560	 * our current estimate of the head.  What we're trying to detect is
1561	 *        1 ... | 0 | 1 | 0...
1562	 *                       ^ binary search ends here
1563	 */
1564	if ((error = xlog_find_verify_cycle(log, start_blk,
1565					 (int)num_scan_bblks, 0, &new_blk)))
1566		goto bp_err;
1567	if (new_blk != -1)
1568		last_blk = new_blk;
1569
1570	/*
1571	 * Potentially backup over partial log record write.  We don't need
1572	 * to search the end of the log because we know it is zero.
1573	 */
1574	error = xlog_find_verify_log_record(log, start_blk, &last_blk, 0);
1575	if (error == 1)
1576		error = -EIO;
1577	if (error)
1578		goto bp_err;
1579
1580	*blk_no = last_blk;
1581bp_err:
1582	xlog_put_bp(bp);
1583	if (error)
1584		return error;
1585	return 1;
1586}
1587
1588/*
1589 * These are simple subroutines used by xlog_clear_stale_blocks() below
1590 * to initialize a buffer full of empty log record headers and write
1591 * them into the log.
1592 */
1593STATIC void
1594xlog_add_record(
1595	struct xlog		*log,
1596	char			*buf,
1597	int			cycle,
1598	int			block,
1599	int			tail_cycle,
1600	int			tail_block)
1601{
1602	xlog_rec_header_t	*recp = (xlog_rec_header_t *)buf;
1603
1604	memset(buf, 0, BBSIZE);
1605	recp->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM);
1606	recp->h_cycle = cpu_to_be32(cycle);
1607	recp->h_version = cpu_to_be32(
1608			xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? 2 : 1);
1609	recp->h_lsn = cpu_to_be64(xlog_assign_lsn(cycle, block));
1610	recp->h_tail_lsn = cpu_to_be64(xlog_assign_lsn(tail_cycle, tail_block));
1611	recp->h_fmt = cpu_to_be32(XLOG_FMT);
1612	memcpy(&recp->h_fs_uuid, &log->l_mp->m_sb.sb_uuid, sizeof(uuid_t));
1613}
1614
1615STATIC int
1616xlog_write_log_records(
1617	struct xlog	*log,
1618	int		cycle,
1619	int		start_block,
1620	int		blocks,
1621	int		tail_cycle,
1622	int		tail_block)
1623{
1624	char		*offset;
1625	xfs_buf_t	*bp;
1626	int		balign, ealign;
1627	int		sectbb = log->l_sectBBsize;
1628	int		end_block = start_block + blocks;
1629	int		bufblks;
1630	int		error = 0;
1631	int		i, j = 0;
1632
1633	/*
1634	 * Greedily allocate a buffer big enough to handle the full
1635	 * range of basic blocks to be written.  If that fails, try
1636	 * a smaller size.  We need to be able to write at least a
1637	 * log sector, or we're out of luck.
1638	 */
1639	bufblks = 1 << ffs(blocks);
1640	while (bufblks > log->l_logBBsize)
1641		bufblks >>= 1;
1642	while (!(bp = xlog_get_bp(log, bufblks))) {
1643		bufblks >>= 1;
1644		if (bufblks < sectbb)
1645			return -ENOMEM;
1646	}
1647
1648	/* We may need to do a read at the start to fill in part of
1649	 * the buffer in the starting sector not covered by the first
1650	 * write below.
1651	 */
1652	balign = round_down(start_block, sectbb);
1653	if (balign != start_block) {
1654		error = xlog_bread_noalign(log, start_block, 1, bp);
1655		if (error)
1656			goto out_put_bp;
1657
1658		j = start_block - balign;
1659	}
1660
1661	for (i = start_block; i < end_block; i += bufblks) {
1662		int		bcount, endcount;
1663
1664		bcount = min(bufblks, end_block - start_block);
1665		endcount = bcount - j;
1666
1667		/* We may need to do a read at the end to fill in part of
1668		 * the buffer in the final sector not covered by the write.
1669		 * If this is the same sector as the above read, skip it.
1670		 */
1671		ealign = round_down(end_block, sectbb);
1672		if (j == 0 && (start_block + endcount > ealign)) {
1673			offset = bp->b_addr + BBTOB(ealign - start_block);
1674			error = xlog_bread_offset(log, ealign, sectbb,
1675							bp, offset);
1676			if (error)
1677				break;
1678
1679		}
1680
1681		offset = xlog_align(log, start_block, endcount, bp);
1682		for (; j < endcount; j++) {
1683			xlog_add_record(log, offset, cycle, i+j,
1684					tail_cycle, tail_block);
1685			offset += BBSIZE;
1686		}
1687		error = xlog_bwrite(log, start_block, endcount, bp);
1688		if (error)
1689			break;
1690		start_block += endcount;
1691		j = 0;
1692	}
1693
1694 out_put_bp:
1695	xlog_put_bp(bp);
1696	return error;
1697}
1698
1699/*
1700 * This routine is called to blow away any incomplete log writes out
1701 * in front of the log head.  We do this so that we won't become confused
1702 * if we come up, write only a little bit more, and then crash again.
1703 * If we leave the partial log records out there, this situation could
1704 * cause us to think those partial writes are valid blocks since they
1705 * have the current cycle number.  We get rid of them by overwriting them
1706 * with empty log records with the old cycle number rather than the
1707 * current one.
1708 *
1709 * The tail lsn is passed in rather than taken from
1710 * the log so that we will not write over the unmount record after a
1711 * clean unmount in a 512 block log.  Doing so would leave the log without
1712 * any valid log records in it until a new one was written.  If we crashed
1713 * during that time we would not be able to recover.
1714 */
1715STATIC int
1716xlog_clear_stale_blocks(
1717	struct xlog	*log,
1718	xfs_lsn_t	tail_lsn)
1719{
1720	int		tail_cycle, head_cycle;
1721	int		tail_block, head_block;
1722	int		tail_distance, max_distance;
1723	int		distance;
1724	int		error;
1725
1726	tail_cycle = CYCLE_LSN(tail_lsn);
1727	tail_block = BLOCK_LSN(tail_lsn);
1728	head_cycle = log->l_curr_cycle;
1729	head_block = log->l_curr_block;
1730
1731	/*
1732	 * Figure out the distance between the new head of the log
1733	 * and the tail.  We want to write over any blocks beyond the
1734	 * head that we may have written just before the crash, but
1735	 * we don't want to overwrite the tail of the log.
1736	 */
1737	if (head_cycle == tail_cycle) {
1738		/*
1739		 * The tail is behind the head in the physical log,
1740		 * so the distance from the head to the tail is the
1741		 * distance from the head to the end of the log plus
1742		 * the distance from the beginning of the log to the
1743		 * tail.
1744		 */
1745		if (unlikely(head_block < tail_block || head_block >= log->l_logBBsize)) {
1746			XFS_ERROR_REPORT("xlog_clear_stale_blocks(1)",
1747					 XFS_ERRLEVEL_LOW, log->l_mp);
1748			return -EFSCORRUPTED;
1749		}
1750		tail_distance = tail_block + (log->l_logBBsize - head_block);
1751	} else {
1752		/*
1753		 * The head is behind the tail in the physical log,
1754		 * so the distance from the head to the tail is just
1755		 * the tail block minus the head block.
1756		 */
1757		if (unlikely(head_block >= tail_block || head_cycle != (tail_cycle + 1))){
1758			XFS_ERROR_REPORT("xlog_clear_stale_blocks(2)",
1759					 XFS_ERRLEVEL_LOW, log->l_mp);
1760			return -EFSCORRUPTED;
1761		}
1762		tail_distance = tail_block - head_block;
1763	}
1764
1765	/*
1766	 * If the head is right up against the tail, we can't clear
1767	 * anything.
1768	 */
1769	if (tail_distance <= 0) {
1770		ASSERT(tail_distance == 0);
1771		return 0;
1772	}
1773
1774	max_distance = XLOG_TOTAL_REC_SHIFT(log);
1775	/*
1776	 * Take the smaller of the maximum amount of outstanding I/O
1777	 * we could have and the distance to the tail to clear out.
1778	 * We take the smaller so that we don't overwrite the tail and
1779	 * we don't waste all day writing from the head to the tail
1780	 * for no reason.
1781	 */
1782	max_distance = MIN(max_distance, tail_distance);
1783
1784	if ((head_block + max_distance) <= log->l_logBBsize) {
1785		/*
1786		 * We can stomp all the blocks we need to without
1787		 * wrapping around the end of the log.  Just do it
1788		 * in a single write.  Use the cycle number of the
1789		 * current cycle minus one so that the log will look like:
1790		 *     n ... | n - 1 ...
1791		 */
1792		error = xlog_write_log_records(log, (head_cycle - 1),
1793				head_block, max_distance, tail_cycle,
1794				tail_block);
1795		if (error)
1796			return error;
1797	} else {
1798		/*
1799		 * We need to wrap around the end of the physical log in
1800		 * order to clear all the blocks.  Do it in two separate
1801		 * I/Os.  The first write should be from the head to the
1802		 * end of the physical log, and it should use the current
1803		 * cycle number minus one just like above.
1804		 */
1805		distance = log->l_logBBsize - head_block;
1806		error = xlog_write_log_records(log, (head_cycle - 1),
1807				head_block, distance, tail_cycle,
1808				tail_block);
1809
1810		if (error)
1811			return error;
1812
1813		/*
1814		 * Now write the blocks at the start of the physical log.
1815		 * This writes the remainder of the blocks we want to clear.
1816		 * It uses the current cycle number since we're now on the
1817		 * same cycle as the head so that we get:
1818		 *    n ... n ... | n - 1 ...
1819		 *    ^^^^^ blocks we're writing
1820		 */
1821		distance = max_distance - (log->l_logBBsize - head_block);
1822		error = xlog_write_log_records(log, head_cycle, 0, distance,
1823				tail_cycle, tail_block);
1824		if (error)
1825			return error;
1826	}
1827
1828	return 0;
1829}
1830
1831/******************************************************************************
1832 *
1833 *		Log recover routines
1834 *
1835 ******************************************************************************
1836 */
1837
1838/*
1839 * Sort the log items in the transaction.
1840 *
1841 * The ordering constraints are defined by the inode allocation and unlink
1842 * behaviour. The rules are:
1843 *
1844 *	1. Every item is only logged once in a given transaction. Hence it
1845 *	   represents the last logged state of the item. Hence ordering is
1846 *	   dependent on the order in which operations need to be performed so
1847 *	   required initial conditions are always met.
1848 *
1849 *	2. Cancelled buffers are recorded in pass 1 in a separate table and
1850 *	   there's nothing to replay from them so we can simply cull them
1851 *	   from the transaction. However, we can't do that until after we've
1852 *	   replayed all the other items because they may be dependent on the
1853 *	   cancelled buffer and replaying the cancelled buffer can remove it
1854 *	   form the cancelled buffer table. Hence they have tobe done last.
1855 *
1856 *	3. Inode allocation buffers must be replayed before inode items that
1857 *	   read the buffer and replay changes into it. For filesystems using the
1858 *	   ICREATE transactions, this means XFS_LI_ICREATE objects need to get
1859 *	   treated the same as inode allocation buffers as they create and
1860 *	   initialise the buffers directly.
1861 *
1862 *	4. Inode unlink buffers must be replayed after inode items are replayed.
1863 *	   This ensures that inodes are completely flushed to the inode buffer
1864 *	   in a "free" state before we remove the unlinked inode list pointer.
1865 *
1866 * Hence the ordering needs to be inode allocation buffers first, inode items
1867 * second, inode unlink buffers third and cancelled buffers last.
1868 *
1869 * But there's a problem with that - we can't tell an inode allocation buffer
1870 * apart from a regular buffer, so we can't separate them. We can, however,
1871 * tell an inode unlink buffer from the others, and so we can separate them out
1872 * from all the other buffers and move them to last.
1873 *
1874 * Hence, 4 lists, in order from head to tail:
1875 *	- buffer_list for all buffers except cancelled/inode unlink buffers
1876 *	- item_list for all non-buffer items
1877 *	- inode_buffer_list for inode unlink buffers
1878 *	- cancel_list for the cancelled buffers
1879 *
1880 * Note that we add objects to the tail of the lists so that first-to-last
1881 * ordering is preserved within the lists. Adding objects to the head of the
1882 * list means when we traverse from the head we walk them in last-to-first
1883 * order. For cancelled buffers and inode unlink buffers this doesn't matter,
1884 * but for all other items there may be specific ordering that we need to
1885 * preserve.
1886 */
1887STATIC int
1888xlog_recover_reorder_trans(
1889	struct xlog		*log,
1890	struct xlog_recover	*trans,
1891	int			pass)
1892{
1893	xlog_recover_item_t	*item, *n;
1894	int			error = 0;
1895	LIST_HEAD(sort_list);
1896	LIST_HEAD(cancel_list);
1897	LIST_HEAD(buffer_list);
1898	LIST_HEAD(inode_buffer_list);
1899	LIST_HEAD(inode_list);
1900
1901	list_splice_init(&trans->r_itemq, &sort_list);
1902	list_for_each_entry_safe(item, n, &sort_list, ri_list) {
1903		xfs_buf_log_format_t	*buf_f = item->ri_buf[0].i_addr;
1904
1905		switch (ITEM_TYPE(item)) {
1906		case XFS_LI_ICREATE:
1907			list_move_tail(&item->ri_list, &buffer_list);
1908			break;
1909		case XFS_LI_BUF:
1910			if (buf_f->blf_flags & XFS_BLF_CANCEL) {
1911				trace_xfs_log_recover_item_reorder_head(log,
1912							trans, item, pass);
1913				list_move(&item->ri_list, &cancel_list);
1914				break;
1915			}
1916			if (buf_f->blf_flags & XFS_BLF_INODE_BUF) {
1917				list_move(&item->ri_list, &inode_buffer_list);
1918				break;
1919			}
1920			list_move_tail(&item->ri_list, &buffer_list);
1921			break;
1922		case XFS_LI_INODE:
1923		case XFS_LI_DQUOT:
1924		case XFS_LI_QUOTAOFF:
1925		case XFS_LI_EFD:
1926		case XFS_LI_EFI:
1927		case XFS_LI_RUI:
1928		case XFS_LI_RUD:
1929		case XFS_LI_CUI:
1930		case XFS_LI_CUD:
1931		case XFS_LI_BUI:
1932		case XFS_LI_BUD:
1933			trace_xfs_log_recover_item_reorder_tail(log,
1934							trans, item, pass);
1935			list_move_tail(&item->ri_list, &inode_list);
1936			break;
1937		default:
1938			xfs_warn(log->l_mp,
1939				"%s: unrecognized type of log operation",
1940				__func__);
1941			ASSERT(0);
1942			/*
1943			 * return the remaining items back to the transaction
1944			 * item list so they can be freed in caller.
1945			 */
1946			if (!list_empty(&sort_list))
1947				list_splice_init(&sort_list, &trans->r_itemq);
1948			error = -EIO;
1949			goto out;
1950		}
1951	}
1952out:
1953	ASSERT(list_empty(&sort_list));
1954	if (!list_empty(&buffer_list))
1955		list_splice(&buffer_list, &trans->r_itemq);
1956	if (!list_empty(&inode_list))
1957		list_splice_tail(&inode_list, &trans->r_itemq);
1958	if (!list_empty(&inode_buffer_list))
1959		list_splice_tail(&inode_buffer_list, &trans->r_itemq);
1960	if (!list_empty(&cancel_list))
1961		list_splice_tail(&cancel_list, &trans->r_itemq);
1962	return error;
1963}
1964
1965/*
1966 * Build up the table of buf cancel records so that we don't replay
1967 * cancelled data in the second pass.  For buffer records that are
1968 * not cancel records, there is nothing to do here so we just return.
1969 *
1970 * If we get a cancel record which is already in the table, this indicates
1971 * that the buffer was cancelled multiple times.  In order to ensure
1972 * that during pass 2 we keep the record in the table until we reach its
1973 * last occurrence in the log, we keep a reference count in the cancel
1974 * record in the table to tell us how many times we expect to see this
1975 * record during the second pass.
1976 */
1977STATIC int
1978xlog_recover_buffer_pass1(
1979	struct xlog			*log,
1980	struct xlog_recover_item	*item)
1981{
1982	xfs_buf_log_format_t	*buf_f = item->ri_buf[0].i_addr;
1983	struct list_head	*bucket;
1984	struct xfs_buf_cancel	*bcp;
1985
1986	/*
1987	 * If this isn't a cancel buffer item, then just return.
1988	 */
1989	if (!(buf_f->blf_flags & XFS_BLF_CANCEL)) {
1990		trace_xfs_log_recover_buf_not_cancel(log, buf_f);
1991		return 0;
1992	}
1993
1994	/*
1995	 * Insert an xfs_buf_cancel record into the hash table of them.
1996	 * If there is already an identical record, bump its reference count.
1997	 */
1998	bucket = XLOG_BUF_CANCEL_BUCKET(log, buf_f->blf_blkno);
1999	list_for_each_entry(bcp, bucket, bc_list) {
2000		if (bcp->bc_blkno == buf_f->blf_blkno &&
2001		    bcp->bc_len == buf_f->blf_len) {
2002			bcp->bc_refcount++;
2003			trace_xfs_log_recover_buf_cancel_ref_inc(log, buf_f);
2004			return 0;
2005		}
2006	}
2007
2008	bcp = kmem_alloc(sizeof(struct xfs_buf_cancel), KM_SLEEP);
2009	bcp->bc_blkno = buf_f->blf_blkno;
2010	bcp->bc_len = buf_f->blf_len;
2011	bcp->bc_refcount = 1;
2012	list_add_tail(&bcp->bc_list, bucket);
2013
2014	trace_xfs_log_recover_buf_cancel_add(log, buf_f);
2015	return 0;
2016}
2017
2018/*
2019 * Check to see whether the buffer being recovered has a corresponding
2020 * entry in the buffer cancel record table. If it is, return the cancel
2021 * buffer structure to the caller.
2022 */
2023STATIC struct xfs_buf_cancel *
2024xlog_peek_buffer_cancelled(
2025	struct xlog		*log,
2026	xfs_daddr_t		blkno,
2027	uint			len,
2028	unsigned short			flags)
2029{
2030	struct list_head	*bucket;
2031	struct xfs_buf_cancel	*bcp;
2032
2033	if (!log->l_buf_cancel_table) {
2034		/* empty table means no cancelled buffers in the log */
2035		ASSERT(!(flags & XFS_BLF_CANCEL));
2036		return NULL;
2037	}
2038
2039	bucket = XLOG_BUF_CANCEL_BUCKET(log, blkno);
2040	list_for_each_entry(bcp, bucket, bc_list) {
2041		if (bcp->bc_blkno == blkno && bcp->bc_len == len)
2042			return bcp;
2043	}
2044
2045	/*
2046	 * We didn't find a corresponding entry in the table, so return 0 so
2047	 * that the buffer is NOT cancelled.
2048	 */
2049	ASSERT(!(flags & XFS_BLF_CANCEL));
2050	return NULL;
2051}
2052
2053/*
2054 * If the buffer is being cancelled then return 1 so that it will be cancelled,
2055 * otherwise return 0.  If the buffer is actually a buffer cancel item
2056 * (XFS_BLF_CANCEL is set), then decrement the refcount on the entry in the
2057 * table and remove it from the table if this is the last reference.
2058 *
2059 * We remove the cancel record from the table when we encounter its last
2060 * occurrence in the log so that if the same buffer is re-used again after its
2061 * last cancellation we actually replay the changes made at that point.
2062 */
2063STATIC int
2064xlog_check_buffer_cancelled(
2065	struct xlog		*log,
2066	xfs_daddr_t		blkno,
2067	uint			len,
2068	unsigned short			flags)
2069{
2070	struct xfs_buf_cancel	*bcp;
2071
2072	bcp = xlog_peek_buffer_cancelled(log, blkno, len, flags);
2073	if (!bcp)
2074		return 0;
2075
2076	/*
2077	 * We've go a match, so return 1 so that the recovery of this buffer
2078	 * is cancelled.  If this buffer is actually a buffer cancel log
2079	 * item, then decrement the refcount on the one in the table and
2080	 * remove it if this is the last reference.
2081	 */
2082	if (flags & XFS_BLF_CANCEL) {
2083		if (--bcp->bc_refcount == 0) {
2084			list_del(&bcp->bc_list);
2085			kmem_free(bcp);
2086		}
2087	}
2088	return 1;
2089}
2090
2091/*
2092 * Perform recovery for a buffer full of inodes.  In these buffers, the only
2093 * data which should be recovered is that which corresponds to the
2094 * di_next_unlinked pointers in the on disk inode structures.  The rest of the
2095 * data for the inodes is always logged through the inodes themselves rather
2096 * than the inode buffer and is recovered in xlog_recover_inode_pass2().
2097 *
2098 * The only time when buffers full of inodes are fully recovered is when the
2099 * buffer is full of newly allocated inodes.  In this case the buffer will
2100 * not be marked as an inode buffer and so will be sent to
2101 * xlog_recover_do_reg_buffer() below during recovery.
2102 */
2103STATIC int
2104xlog_recover_do_inode_buffer(
2105	struct xfs_mount	*mp,
2106	xlog_recover_item_t	*item,
2107	struct xfs_buf		*bp,
2108	xfs_buf_log_format_t	*buf_f)
2109{
2110	int			i;
2111	int			item_index = 0;
2112	int			bit = 0;
2113	int			nbits = 0;
2114	int			reg_buf_offset = 0;
2115	int			reg_buf_bytes = 0;
2116	int			next_unlinked_offset;
2117	int			inodes_per_buf;
2118	xfs_agino_t		*logged_nextp;
2119	xfs_agino_t		*buffer_nextp;
2120
2121	trace_xfs_log_recover_buf_inode_buf(mp->m_log, buf_f);
2122
2123	/*
2124	 * Post recovery validation only works properly on CRC enabled
2125	 * filesystems.
2126	 */
2127	if (xfs_sb_version_hascrc(&mp->m_sb))
2128		bp->b_ops = &xfs_inode_buf_ops;
2129
2130	inodes_per_buf = BBTOB(bp->b_io_length) >> mp->m_sb.sb_inodelog;
2131	for (i = 0; i < inodes_per_buf; i++) {
2132		next_unlinked_offset = (i * mp->m_sb.sb_inodesize) +
2133			offsetof(xfs_dinode_t, di_next_unlinked);
2134
2135		while (next_unlinked_offset >=
2136		       (reg_buf_offset + reg_buf_bytes)) {
2137			/*
2138			 * The next di_next_unlinked field is beyond
2139			 * the current logged region.  Find the next
2140			 * logged region that contains or is beyond
2141			 * the current di_next_unlinked field.
2142			 */
2143			bit += nbits;
2144			bit = xfs_next_bit(buf_f->blf_data_map,
2145					   buf_f->blf_map_size, bit);
2146
2147			/*
2148			 * If there are no more logged regions in the
2149			 * buffer, then we're done.
2150			 */
2151			if (bit == -1)
2152				return 0;
2153
2154			nbits = xfs_contig_bits(buf_f->blf_data_map,
2155						buf_f->blf_map_size, bit);
2156			ASSERT(nbits > 0);
2157			reg_buf_offset = bit << XFS_BLF_SHIFT;
2158			reg_buf_bytes = nbits << XFS_BLF_SHIFT;
2159			item_index++;
2160		}
2161
2162		/*
2163		 * If the current logged region starts after the current
2164		 * di_next_unlinked field, then move on to the next
2165		 * di_next_unlinked field.
2166		 */
2167		if (next_unlinked_offset < reg_buf_offset)
2168			continue;
2169
2170		ASSERT(item->ri_buf[item_index].i_addr != NULL);
2171		ASSERT((item->ri_buf[item_index].i_len % XFS_BLF_CHUNK) == 0);
2172		ASSERT((reg_buf_offset + reg_buf_bytes) <=
2173							BBTOB(bp->b_io_length));
2174
2175		/*
2176		 * The current logged region contains a copy of the
2177		 * current di_next_unlinked field.  Extract its value
2178		 * and copy it to the buffer copy.
2179		 */
2180		logged_nextp = item->ri_buf[item_index].i_addr +
2181				next_unlinked_offset - reg_buf_offset;
2182		if (unlikely(*logged_nextp == 0)) {
2183			xfs_alert(mp,
2184		"Bad inode buffer log record (ptr = 0x%p, bp = 0x%p). "
2185		"Trying to replay bad (0) inode di_next_unlinked field.",
2186				item, bp);
2187			XFS_ERROR_REPORT("xlog_recover_do_inode_buf",
2188					 XFS_ERRLEVEL_LOW, mp);
2189			return -EFSCORRUPTED;
2190		}
2191
2192		buffer_nextp = xfs_buf_offset(bp, next_unlinked_offset);
2193		*buffer_nextp = *logged_nextp;
2194
2195		/*
2196		 * If necessary, recalculate the CRC in the on-disk inode. We
2197		 * have to leave the inode in a consistent state for whoever
2198		 * reads it next....
2199		 */
2200		xfs_dinode_calc_crc(mp,
2201				xfs_buf_offset(bp, i * mp->m_sb.sb_inodesize));
2202
2203	}
2204
2205	return 0;
2206}
2207
2208/*
2209 * V5 filesystems know the age of the buffer on disk being recovered. We can
2210 * have newer objects on disk than we are replaying, and so for these cases we
2211 * don't want to replay the current change as that will make the buffer contents
2212 * temporarily invalid on disk.
2213 *
2214 * The magic number might not match the buffer type we are going to recover
2215 * (e.g. reallocated blocks), so we ignore the xfs_buf_log_format flags.  Hence
2216 * extract the LSN of the existing object in the buffer based on it's current
2217 * magic number.  If we don't recognise the magic number in the buffer, then
2218 * return a LSN of -1 so that the caller knows it was an unrecognised block and
2219 * so can recover the buffer.
2220 *
2221 * Note: we cannot rely solely on magic number matches to determine that the
2222 * buffer has a valid LSN - we also need to verify that it belongs to this
2223 * filesystem, so we need to extract the object's LSN and compare it to that
2224 * which we read from the superblock. If the UUIDs don't match, then we've got a
2225 * stale metadata block from an old filesystem instance that we need to recover
2226 * over the top of.
2227 */
2228static xfs_lsn_t
2229xlog_recover_get_buf_lsn(
2230	struct xfs_mount	*mp,
2231	struct xfs_buf		*bp)
2232{
2233	__uint32_t		magic32;
2234	__uint16_t		magic16;
2235	__uint16_t		magicda;
2236	void			*blk = bp->b_addr;
2237	uuid_t			*uuid;
2238	xfs_lsn_t		lsn = -1;
2239
2240	/* v4 filesystems always recover immediately */
2241	if (!xfs_sb_version_hascrc(&mp->m_sb))
2242		goto recover_immediately;
2243
2244	magic32 = be32_to_cpu(*(__be32 *)blk);
2245	switch (magic32) {
2246	case XFS_ABTB_CRC_MAGIC:
2247	case XFS_ABTC_CRC_MAGIC:
2248	case XFS_ABTB_MAGIC:
2249	case XFS_ABTC_MAGIC:
2250	case XFS_RMAP_CRC_MAGIC:
2251	case XFS_REFC_CRC_MAGIC:
2252	case XFS_IBT_CRC_MAGIC:
2253	case XFS_IBT_MAGIC: {
2254		struct xfs_btree_block *btb = blk;
2255
2256		lsn = be64_to_cpu(btb->bb_u.s.bb_lsn);
2257		uuid = &btb->bb_u.s.bb_uuid;
2258		break;
2259	}
2260	case XFS_BMAP_CRC_MAGIC:
2261	case XFS_BMAP_MAGIC: {
2262		struct xfs_btree_block *btb = blk;
2263
2264		lsn = be64_to_cpu(btb->bb_u.l.bb_lsn);
2265		uuid = &btb->bb_u.l.bb_uuid;
2266		break;
2267	}
2268	case XFS_AGF_MAGIC:
2269		lsn = be64_to_cpu(((struct xfs_agf *)blk)->agf_lsn);
2270		uuid = &((struct xfs_agf *)blk)->agf_uuid;
2271		break;
2272	case XFS_AGFL_MAGIC:
2273		lsn = be64_to_cpu(((struct xfs_agfl *)blk)->agfl_lsn);
2274		uuid = &((struct xfs_agfl *)blk)->agfl_uuid;
2275		break;
2276	case XFS_AGI_MAGIC:
2277		lsn = be64_to_cpu(((struct xfs_agi *)blk)->agi_lsn);
2278		uuid = &((struct xfs_agi *)blk)->agi_uuid;
2279		break;
2280	case XFS_SYMLINK_MAGIC:
2281		lsn = be64_to_cpu(((struct xfs_dsymlink_hdr *)blk)->sl_lsn);
2282		uuid = &((struct xfs_dsymlink_hdr *)blk)->sl_uuid;
2283		break;
2284	case XFS_DIR3_BLOCK_MAGIC:
2285	case XFS_DIR3_DATA_MAGIC:
2286	case XFS_DIR3_FREE_MAGIC:
2287		lsn = be64_to_cpu(((struct xfs_dir3_blk_hdr *)blk)->lsn);
2288		uuid = &((struct xfs_dir3_blk_hdr *)blk)->uuid;
2289		break;
2290	case XFS_ATTR3_RMT_MAGIC:
2291		/*
2292		 * Remote attr blocks are written synchronously, rather than
2293		 * being logged. That means they do not contain a valid LSN
2294		 * (i.e. transactionally ordered) in them, and hence any time we
2295		 * see a buffer to replay over the top of a remote attribute
2296		 * block we should simply do so.
2297		 */
2298		goto recover_immediately;
2299	case XFS_SB_MAGIC:
2300		/*
2301		 * superblock uuids are magic. We may or may not have a
2302		 * sb_meta_uuid on disk, but it will be set in the in-core
2303		 * superblock. We set the uuid pointer for verification
2304		 * according to the superblock feature mask to ensure we check
2305		 * the relevant UUID in the superblock.
2306		 */
2307		lsn = be64_to_cpu(((struct xfs_dsb *)blk)->sb_lsn);
2308		if (xfs_sb_version_hasmetauuid(&mp->m_sb))
2309			uuid = &((struct xfs_dsb *)blk)->sb_meta_uuid;
2310		else
2311			uuid = &((struct xfs_dsb *)blk)->sb_uuid;
2312		break;
2313	default:
2314		break;
2315	}
2316
2317	if (lsn != (xfs_lsn_t)-1) {
2318		if (!uuid_equal(&mp->m_sb.sb_meta_uuid, uuid))
2319			goto recover_immediately;
2320		return lsn;
2321	}
2322
2323	magicda = be16_to_cpu(((struct xfs_da_blkinfo *)blk)->magic);
2324	switch (magicda) {
2325	case XFS_DIR3_LEAF1_MAGIC:
2326	case XFS_DIR3_LEAFN_MAGIC:
2327	case XFS_DA3_NODE_MAGIC:
2328		lsn = be64_to_cpu(((struct xfs_da3_blkinfo *)blk)->lsn);
2329		uuid = &((struct xfs_da3_blkinfo *)blk)->uuid;
2330		break;
2331	default:
2332		break;
2333	}
2334
2335	if (lsn != (xfs_lsn_t)-1) {
2336		if (!uuid_equal(&mp->m_sb.sb_uuid, uuid))
2337			goto recover_immediately;
2338		return lsn;
2339	}
2340
2341	/*
2342	 * We do individual object checks on dquot and inode buffers as they
2343	 * have their own individual LSN records. Also, we could have a stale
2344	 * buffer here, so we have to at least recognise these buffer types.
2345	 *
2346	 * A notd complexity here is inode unlinked list processing - it logs
2347	 * the inode directly in the buffer, but we don't know which inodes have
2348	 * been modified, and there is no global buffer LSN. Hence we need to
2349	 * recover all inode buffer types immediately. This problem will be
2350	 * fixed by logical logging of the unlinked list modifications.
2351	 */
2352	magic16 = be16_to_cpu(*(__be16 *)blk);
2353	switch (magic16) {
2354	case XFS_DQUOT_MAGIC:
2355	case XFS_DINODE_MAGIC:
2356		goto recover_immediately;
2357	default:
2358		break;
2359	}
2360
2361	/* unknown buffer contents, recover immediately */
2362
2363recover_immediately:
2364	return (xfs_lsn_t)-1;
2365
2366}
2367
2368/*
2369 * Validate the recovered buffer is of the correct type and attach the
2370 * appropriate buffer operations to them for writeback. Magic numbers are in a
2371 * few places:
2372 *	the first 16 bits of the buffer (inode buffer, dquot buffer),
2373 *	the first 32 bits of the buffer (most blocks),
2374 *	inside a struct xfs_da_blkinfo at the start of the buffer.
2375 */
2376static void
2377xlog_recover_validate_buf_type(
2378	struct xfs_mount	*mp,
2379	struct xfs_buf		*bp,
2380	xfs_buf_log_format_t	*buf_f,
2381	xfs_lsn_t		current_lsn)
2382{
2383	struct xfs_da_blkinfo	*info = bp->b_addr;
2384	__uint32_t		magic32;
2385	__uint16_t		magic16;
2386	__uint16_t		magicda;
2387	char			*warnmsg = NULL;
2388
2389	/*
2390	 * We can only do post recovery validation on items on CRC enabled
2391	 * fielsystems as we need to know when the buffer was written to be able
2392	 * to determine if we should have replayed the item. If we replay old
2393	 * metadata over a newer buffer, then it will enter a temporarily
2394	 * inconsistent state resulting in verification failures. Hence for now
2395	 * just avoid the verification stage for non-crc filesystems
2396	 */
2397	if (!xfs_sb_version_hascrc(&mp->m_sb))
2398		return;
2399
2400	magic32 = be32_to_cpu(*(__be32 *)bp->b_addr);
2401	magic16 = be16_to_cpu(*(__be16*)bp->b_addr);
2402	magicda = be16_to_cpu(info->magic);
2403	switch (xfs_blft_from_flags(buf_f)) {
2404	case XFS_BLFT_BTREE_BUF:
2405		switch (magic32) {
2406		case XFS_ABTB_CRC_MAGIC:
2407		case XFS_ABTC_CRC_MAGIC:
2408		case XFS_ABTB_MAGIC:
2409		case XFS_ABTC_MAGIC:
2410			bp->b_ops = &xfs_allocbt_buf_ops;
2411			break;
2412		case XFS_IBT_CRC_MAGIC:
2413		case XFS_FIBT_CRC_MAGIC:
2414		case XFS_IBT_MAGIC:
2415		case XFS_FIBT_MAGIC:
2416			bp->b_ops = &xfs_inobt_buf_ops;
2417			break;
2418		case XFS_BMAP_CRC_MAGIC:
2419		case XFS_BMAP_MAGIC:
2420			bp->b_ops = &xfs_bmbt_buf_ops;
2421			break;
2422		case XFS_RMAP_CRC_MAGIC:
2423			bp->b_ops = &xfs_rmapbt_buf_ops;
2424			break;
2425		case XFS_REFC_CRC_MAGIC:
2426			bp->b_ops = &xfs_refcountbt_buf_ops;
2427			break;
2428		default:
2429			warnmsg = "Bad btree block magic!";
2430			break;
2431		}
2432		break;
2433	case XFS_BLFT_AGF_BUF:
2434		if (magic32 != XFS_AGF_MAGIC) {
2435			warnmsg = "Bad AGF block magic!";
2436			break;
2437		}
2438		bp->b_ops = &xfs_agf_buf_ops;
2439		break;
2440	case XFS_BLFT_AGFL_BUF:
2441		if (magic32 != XFS_AGFL_MAGIC) {
2442			warnmsg = "Bad AGFL block magic!";
2443			break;
2444		}
2445		bp->b_ops = &xfs_agfl_buf_ops;
2446		break;
2447	case XFS_BLFT_AGI_BUF:
2448		if (magic32 != XFS_AGI_MAGIC) {
2449			warnmsg = "Bad AGI block magic!";
2450			break;
2451		}
2452		bp->b_ops = &xfs_agi_buf_ops;
2453		break;
2454	case XFS_BLFT_UDQUOT_BUF:
2455	case XFS_BLFT_PDQUOT_BUF:
2456	case XFS_BLFT_GDQUOT_BUF:
2457#ifdef CONFIG_XFS_QUOTA
2458		if (magic16 != XFS_DQUOT_MAGIC) {
2459			warnmsg = "Bad DQUOT block magic!";
2460			break;
2461		}
2462		bp->b_ops = &xfs_dquot_buf_ops;
2463#else
2464		xfs_alert(mp,
2465	"Trying to recover dquots without QUOTA support built in!");
2466		ASSERT(0);
2467#endif
2468		break;
2469	case XFS_BLFT_DINO_BUF:
2470		if (magic16 != XFS_DINODE_MAGIC) {
2471			warnmsg = "Bad INODE block magic!";
2472			break;
2473		}
2474		bp->b_ops = &xfs_inode_buf_ops;
2475		break;
2476	case XFS_BLFT_SYMLINK_BUF:
2477		if (magic32 != XFS_SYMLINK_MAGIC) {
2478			warnmsg = "Bad symlink block magic!";
2479			break;
2480		}
2481		bp->b_ops = &xfs_symlink_buf_ops;
2482		break;
2483	case XFS_BLFT_DIR_BLOCK_BUF:
2484		if (magic32 != XFS_DIR2_BLOCK_MAGIC &&
2485		    magic32 != XFS_DIR3_BLOCK_MAGIC) {
2486			warnmsg = "Bad dir block magic!";
2487			break;
2488		}
2489		bp->b_ops = &xfs_dir3_block_buf_ops;
2490		break;
2491	case XFS_BLFT_DIR_DATA_BUF:
2492		if (magic32 != XFS_DIR2_DATA_MAGIC &&
2493		    magic32 != XFS_DIR3_DATA_MAGIC) {
2494			warnmsg = "Bad dir data magic!";
2495			break;
2496		}
2497		bp->b_ops = &xfs_dir3_data_buf_ops;
2498		break;
2499	case XFS_BLFT_DIR_FREE_BUF:
2500		if (magic32 != XFS_DIR2_FREE_MAGIC &&
2501		    magic32 != XFS_DIR3_FREE_MAGIC) {
2502			warnmsg = "Bad dir3 free magic!";
2503			break;
2504		}
2505		bp->b_ops = &xfs_dir3_free_buf_ops;
2506		break;
2507	case XFS_BLFT_DIR_LEAF1_BUF:
2508		if (magicda != XFS_DIR2_LEAF1_MAGIC &&
2509		    magicda != XFS_DIR3_LEAF1_MAGIC) {
2510			warnmsg = "Bad dir leaf1 magic!";
2511			break;
2512		}
2513		bp->b_ops = &xfs_dir3_leaf1_buf_ops;
2514		break;
2515	case XFS_BLFT_DIR_LEAFN_BUF:
2516		if (magicda != XFS_DIR2_LEAFN_MAGIC &&
2517		    magicda != XFS_DIR3_LEAFN_MAGIC) {
2518			warnmsg = "Bad dir leafn magic!";
2519			break;
2520		}
2521		bp->b_ops = &xfs_dir3_leafn_buf_ops;
2522		break;
2523	case XFS_BLFT_DA_NODE_BUF:
2524		if (magicda != XFS_DA_NODE_MAGIC &&
2525		    magicda != XFS_DA3_NODE_MAGIC) {
2526			warnmsg = "Bad da node magic!";
2527			break;
2528		}
2529		bp->b_ops = &xfs_da3_node_buf_ops;
2530		break;
2531	case XFS_BLFT_ATTR_LEAF_BUF:
2532		if (magicda != XFS_ATTR_LEAF_MAGIC &&
2533		    magicda != XFS_ATTR3_LEAF_MAGIC) {
2534			warnmsg = "Bad attr leaf magic!";
2535			break;
2536		}
2537		bp->b_ops = &xfs_attr3_leaf_buf_ops;
2538		break;
2539	case XFS_BLFT_ATTR_RMT_BUF:
2540		if (magic32 != XFS_ATTR3_RMT_MAGIC) {
2541			warnmsg = "Bad attr remote magic!";
2542			break;
2543		}
2544		bp->b_ops = &xfs_attr3_rmt_buf_ops;
2545		break;
2546	case XFS_BLFT_SB_BUF:
2547		if (magic32 != XFS_SB_MAGIC) {
2548			warnmsg = "Bad SB block magic!";
2549			break;
2550		}
2551		bp->b_ops = &xfs_sb_buf_ops;
2552		break;
2553#ifdef CONFIG_XFS_RT
2554	case XFS_BLFT_RTBITMAP_BUF:
2555	case XFS_BLFT_RTSUMMARY_BUF:
2556		/* no magic numbers for verification of RT buffers */
2557		bp->b_ops = &xfs_rtbuf_ops;
2558		break;
2559#endif /* CONFIG_XFS_RT */
2560	default:
2561		xfs_warn(mp, "Unknown buffer type %d!",
2562			 xfs_blft_from_flags(buf_f));
2563		break;
2564	}
2565
2566	/*
2567	 * Nothing else to do in the case of a NULL current LSN as this means
2568	 * the buffer is more recent than the change in the log and will be
2569	 * skipped.
2570	 */
2571	if (current_lsn == NULLCOMMITLSN)
2572		return;
2573
2574	if (warnmsg) {
2575		xfs_warn(mp, warnmsg);
2576		ASSERT(0);
2577	}
2578
2579	/*
2580	 * We must update the metadata LSN of the buffer as it is written out to
2581	 * ensure that older transactions never replay over this one and corrupt
2582	 * the buffer. This can occur if log recovery is interrupted at some
2583	 * point after the current transaction completes, at which point a
2584	 * subsequent mount starts recovery from the beginning.
2585	 *
2586	 * Write verifiers update the metadata LSN from log items attached to
2587	 * the buffer. Therefore, initialize a bli purely to carry the LSN to
2588	 * the verifier. We'll clean it up in our ->iodone() callback.
2589	 */
2590	if (bp->b_ops) {
2591		struct xfs_buf_log_item	*bip;
2592
2593		ASSERT(!bp->b_iodone || bp->b_iodone == xlog_recover_iodone);
2594		bp->b_iodone = xlog_recover_iodone;
2595		xfs_buf_item_init(bp, mp);
2596		bip = bp->b_fspriv;
2597		bip->bli_item.li_lsn = current_lsn;
2598	}
2599}
2600
2601/*
2602 * Perform a 'normal' buffer recovery.  Each logged region of the
2603 * buffer should be copied over the corresponding region in the
2604 * given buffer.  The bitmap in the buf log format structure indicates
2605 * where to place the logged data.
2606 */
2607STATIC void
2608xlog_recover_do_reg_buffer(
2609	struct xfs_mount	*mp,
2610	xlog_recover_item_t	*item,
2611	struct xfs_buf		*bp,
2612	xfs_buf_log_format_t	*buf_f,
2613	xfs_lsn_t		current_lsn)
2614{
2615	int			i;
2616	int			bit;
2617	int			nbits;
2618	int                     error;
2619
2620	trace_xfs_log_recover_buf_reg_buf(mp->m_log, buf_f);
2621
2622	bit = 0;
2623	i = 1;  /* 0 is the buf format structure */
2624	while (1) {
2625		bit = xfs_next_bit(buf_f->blf_data_map,
2626				   buf_f->blf_map_size, bit);
2627		if (bit == -1)
2628			break;
2629		nbits = xfs_contig_bits(buf_f->blf_data_map,
2630					buf_f->blf_map_size, bit);
2631		ASSERT(nbits > 0);
2632		ASSERT(item->ri_buf[i].i_addr != NULL);
2633		ASSERT(item->ri_buf[i].i_len % XFS_BLF_CHUNK == 0);
2634		ASSERT(BBTOB(bp->b_io_length) >=
2635		       ((uint)bit << XFS_BLF_SHIFT) + (nbits << XFS_BLF_SHIFT));
2636
2637		/*
2638		 * The dirty regions logged in the buffer, even though
2639		 * contiguous, may span multiple chunks. This is because the
2640		 * dirty region may span a physical page boundary in a buffer
2641		 * and hence be split into two separate vectors for writing into
2642		 * the log. Hence we need to trim nbits back to the length of
2643		 * the current region being copied out of the log.
2644		 */
2645		if (item->ri_buf[i].i_len < (nbits << XFS_BLF_SHIFT))
2646			nbits = item->ri_buf[i].i_len >> XFS_BLF_SHIFT;
2647
2648		/*
2649		 * Do a sanity check if this is a dquot buffer. Just checking
2650		 * the first dquot in the buffer should do. XXXThis is
2651		 * probably a good thing to do for other buf types also.
2652		 */
2653		error = 0;
2654		if (buf_f->blf_flags &
2655		   (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) {
2656			if (item->ri_buf[i].i_addr == NULL) {
2657				xfs_alert(mp,
2658					"XFS: NULL dquot in %s.", __func__);
2659				goto next;
2660			}
2661			if (item->ri_buf[i].i_len < sizeof(xfs_disk_dquot_t)) {
2662				xfs_alert(mp,
2663					"XFS: dquot too small (%d) in %s.",
2664					item->ri_buf[i].i_len, __func__);
2665				goto next;
2666			}
2667			error = xfs_dqcheck(mp, item->ri_buf[i].i_addr,
2668					       -1, 0, XFS_QMOPT_DOWARN,
2669					       "dquot_buf_recover");
2670			if (error)
 
 
2671				goto next;
 
2672		}
2673
2674		memcpy(xfs_buf_offset(bp,
2675			(uint)bit << XFS_BLF_SHIFT),	/* dest */
2676			item->ri_buf[i].i_addr,		/* source */
2677			nbits<<XFS_BLF_SHIFT);		/* length */
2678 next:
2679		i++;
2680		bit += nbits;
2681	}
2682
2683	/* Shouldn't be any more regions */
2684	ASSERT(i == item->ri_total);
2685
2686	xlog_recover_validate_buf_type(mp, bp, buf_f, current_lsn);
2687}
2688
2689/*
2690 * Perform a dquot buffer recovery.
2691 * Simple algorithm: if we have found a QUOTAOFF log item of the same type
2692 * (ie. USR or GRP), then just toss this buffer away; don't recover it.
2693 * Else, treat it as a regular buffer and do recovery.
2694 *
2695 * Return false if the buffer was tossed and true if we recovered the buffer to
2696 * indicate to the caller if the buffer needs writing.
2697 */
2698STATIC bool
2699xlog_recover_do_dquot_buffer(
2700	struct xfs_mount		*mp,
2701	struct xlog			*log,
2702	struct xlog_recover_item	*item,
2703	struct xfs_buf			*bp,
2704	struct xfs_buf_log_format	*buf_f)
2705{
2706	uint			type;
2707
2708	trace_xfs_log_recover_buf_dquot_buf(log, buf_f);
2709
2710	/*
2711	 * Filesystems are required to send in quota flags at mount time.
2712	 */
2713	if (!mp->m_qflags)
2714		return false;
2715
2716	type = 0;
2717	if (buf_f->blf_flags & XFS_BLF_UDQUOT_BUF)
2718		type |= XFS_DQ_USER;
2719	if (buf_f->blf_flags & XFS_BLF_PDQUOT_BUF)
2720		type |= XFS_DQ_PROJ;
2721	if (buf_f->blf_flags & XFS_BLF_GDQUOT_BUF)
2722		type |= XFS_DQ_GROUP;
2723	/*
2724	 * This type of quotas was turned off, so ignore this buffer
2725	 */
2726	if (log->l_quotaoffs_flag & type)
2727		return false;
2728
2729	xlog_recover_do_reg_buffer(mp, item, bp, buf_f, NULLCOMMITLSN);
2730	return true;
2731}
2732
2733/*
2734 * This routine replays a modification made to a buffer at runtime.
2735 * There are actually two types of buffer, regular and inode, which
2736 * are handled differently.  Inode buffers are handled differently
2737 * in that we only recover a specific set of data from them, namely
2738 * the inode di_next_unlinked fields.  This is because all other inode
2739 * data is actually logged via inode records and any data we replay
2740 * here which overlaps that may be stale.
2741 *
2742 * When meta-data buffers are freed at run time we log a buffer item
2743 * with the XFS_BLF_CANCEL bit set to indicate that previous copies
2744 * of the buffer in the log should not be replayed at recovery time.
2745 * This is so that if the blocks covered by the buffer are reused for
2746 * file data before we crash we don't end up replaying old, freed
2747 * meta-data into a user's file.
2748 *
2749 * To handle the cancellation of buffer log items, we make two passes
2750 * over the log during recovery.  During the first we build a table of
2751 * those buffers which have been cancelled, and during the second we
2752 * only replay those buffers which do not have corresponding cancel
2753 * records in the table.  See xlog_recover_buffer_pass[1,2] above
2754 * for more details on the implementation of the table of cancel records.
2755 */
2756STATIC int
2757xlog_recover_buffer_pass2(
2758	struct xlog			*log,
2759	struct list_head		*buffer_list,
2760	struct xlog_recover_item	*item,
2761	xfs_lsn_t			current_lsn)
2762{
2763	xfs_buf_log_format_t	*buf_f = item->ri_buf[0].i_addr;
2764	xfs_mount_t		*mp = log->l_mp;
2765	xfs_buf_t		*bp;
2766	int			error;
2767	uint			buf_flags;
2768	xfs_lsn_t		lsn;
2769
2770	/*
2771	 * In this pass we only want to recover all the buffers which have
2772	 * not been cancelled and are not cancellation buffers themselves.
2773	 */
2774	if (xlog_check_buffer_cancelled(log, buf_f->blf_blkno,
2775			buf_f->blf_len, buf_f->blf_flags)) {
2776		trace_xfs_log_recover_buf_cancel(log, buf_f);
2777		return 0;
2778	}
2779
2780	trace_xfs_log_recover_buf_recover(log, buf_f);
2781
2782	buf_flags = 0;
2783	if (buf_f->blf_flags & XFS_BLF_INODE_BUF)
2784		buf_flags |= XBF_UNMAPPED;
2785
2786	bp = xfs_buf_read(mp->m_ddev_targp, buf_f->blf_blkno, buf_f->blf_len,
2787			  buf_flags, NULL);
2788	if (!bp)
2789		return -ENOMEM;
2790	error = bp->b_error;
2791	if (error) {
2792		xfs_buf_ioerror_alert(bp, "xlog_recover_do..(read#1)");
2793		goto out_release;
2794	}
2795
2796	/*
2797	 * Recover the buffer only if we get an LSN from it and it's less than
2798	 * the lsn of the transaction we are replaying.
2799	 *
2800	 * Note that we have to be extremely careful of readahead here.
2801	 * Readahead does not attach verfiers to the buffers so if we don't
2802	 * actually do any replay after readahead because of the LSN we found
2803	 * in the buffer if more recent than that current transaction then we
2804	 * need to attach the verifier directly. Failure to do so can lead to
2805	 * future recovery actions (e.g. EFI and unlinked list recovery) can
2806	 * operate on the buffers and they won't get the verifier attached. This
2807	 * can lead to blocks on disk having the correct content but a stale
2808	 * CRC.
2809	 *
2810	 * It is safe to assume these clean buffers are currently up to date.
2811	 * If the buffer is dirtied by a later transaction being replayed, then
2812	 * the verifier will be reset to match whatever recover turns that
2813	 * buffer into.
2814	 */
2815	lsn = xlog_recover_get_buf_lsn(mp, bp);
2816	if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) {
2817		trace_xfs_log_recover_buf_skip(log, buf_f);
2818		xlog_recover_validate_buf_type(mp, bp, buf_f, NULLCOMMITLSN);
2819		goto out_release;
2820	}
2821
2822	if (buf_f->blf_flags & XFS_BLF_INODE_BUF) {
2823		error = xlog_recover_do_inode_buffer(mp, item, bp, buf_f);
2824		if (error)
2825			goto out_release;
2826	} else if (buf_f->blf_flags &
2827		  (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) {
2828		bool	dirty;
2829
2830		dirty = xlog_recover_do_dquot_buffer(mp, log, item, bp, buf_f);
2831		if (!dirty)
2832			goto out_release;
2833	} else {
2834		xlog_recover_do_reg_buffer(mp, item, bp, buf_f, current_lsn);
2835	}
2836
2837	/*
2838	 * Perform delayed write on the buffer.  Asynchronous writes will be
2839	 * slower when taking into account all the buffers to be flushed.
2840	 *
2841	 * Also make sure that only inode buffers with good sizes stay in
2842	 * the buffer cache.  The kernel moves inodes in buffers of 1 block
2843	 * or mp->m_inode_cluster_size bytes, whichever is bigger.  The inode
2844	 * buffers in the log can be a different size if the log was generated
2845	 * by an older kernel using unclustered inode buffers or a newer kernel
2846	 * running with a different inode cluster size.  Regardless, if the
2847	 * the inode buffer size isn't MAX(blocksize, mp->m_inode_cluster_size)
2848	 * for *our* value of mp->m_inode_cluster_size, then we need to keep
2849	 * the buffer out of the buffer cache so that the buffer won't
2850	 * overlap with future reads of those inodes.
2851	 */
2852	if (XFS_DINODE_MAGIC ==
2853	    be16_to_cpu(*((__be16 *)xfs_buf_offset(bp, 0))) &&
2854	    (BBTOB(bp->b_io_length) != MAX(log->l_mp->m_sb.sb_blocksize,
2855			(__uint32_t)log->l_mp->m_inode_cluster_size))) {
2856		xfs_buf_stale(bp);
2857		error = xfs_bwrite(bp);
2858	} else {
2859		ASSERT(bp->b_target->bt_mount == mp);
2860		bp->b_iodone = xlog_recover_iodone;
2861		xfs_buf_delwri_queue(bp, buffer_list);
2862	}
2863
2864out_release:
2865	xfs_buf_relse(bp);
2866	return error;
2867}
2868
2869/*
2870 * Inode fork owner changes
2871 *
2872 * If we have been told that we have to reparent the inode fork, it's because an
2873 * extent swap operation on a CRC enabled filesystem has been done and we are
2874 * replaying it. We need to walk the BMBT of the appropriate fork and change the
2875 * owners of it.
2876 *
2877 * The complexity here is that we don't have an inode context to work with, so
2878 * after we've replayed the inode we need to instantiate one.  This is where the
2879 * fun begins.
2880 *
2881 * We are in the middle of log recovery, so we can't run transactions. That
2882 * means we cannot use cache coherent inode instantiation via xfs_iget(), as
2883 * that will result in the corresponding iput() running the inode through
2884 * xfs_inactive(). If we've just replayed an inode core that changes the link
2885 * count to zero (i.e. it's been unlinked), then xfs_inactive() will run
2886 * transactions (bad!).
2887 *
2888 * So, to avoid this, we instantiate an inode directly from the inode core we've
2889 * just recovered. We have the buffer still locked, and all we really need to
2890 * instantiate is the inode core and the forks being modified. We can do this
2891 * manually, then run the inode btree owner change, and then tear down the
2892 * xfs_inode without having to run any transactions at all.
2893 *
2894 * Also, because we don't have a transaction context available here but need to
2895 * gather all the buffers we modify for writeback so we pass the buffer_list
2896 * instead for the operation to use.
2897 */
2898
2899STATIC int
2900xfs_recover_inode_owner_change(
2901	struct xfs_mount	*mp,
2902	struct xfs_dinode	*dip,
2903	struct xfs_inode_log_format *in_f,
2904	struct list_head	*buffer_list)
2905{
2906	struct xfs_inode	*ip;
2907	int			error;
2908
2909	ASSERT(in_f->ilf_fields & (XFS_ILOG_DOWNER|XFS_ILOG_AOWNER));
2910
2911	ip = xfs_inode_alloc(mp, in_f->ilf_ino);
2912	if (!ip)
2913		return -ENOMEM;
2914
2915	/* instantiate the inode */
2916	xfs_inode_from_disk(ip, dip);
2917	ASSERT(ip->i_d.di_version >= 3);
2918
2919	error = xfs_iformat_fork(ip, dip);
2920	if (error)
2921		goto out_free_ip;
2922
 
 
 
 
2923
2924	if (in_f->ilf_fields & XFS_ILOG_DOWNER) {
2925		ASSERT(in_f->ilf_fields & XFS_ILOG_DBROOT);
2926		error = xfs_bmbt_change_owner(NULL, ip, XFS_DATA_FORK,
2927					      ip->i_ino, buffer_list);
2928		if (error)
2929			goto out_free_ip;
2930	}
2931
2932	if (in_f->ilf_fields & XFS_ILOG_AOWNER) {
2933		ASSERT(in_f->ilf_fields & XFS_ILOG_ABROOT);
2934		error = xfs_bmbt_change_owner(NULL, ip, XFS_ATTR_FORK,
2935					      ip->i_ino, buffer_list);
2936		if (error)
2937			goto out_free_ip;
2938	}
2939
2940out_free_ip:
2941	xfs_inode_free(ip);
2942	return error;
2943}
2944
2945STATIC int
2946xlog_recover_inode_pass2(
2947	struct xlog			*log,
2948	struct list_head		*buffer_list,
2949	struct xlog_recover_item	*item,
2950	xfs_lsn_t			current_lsn)
2951{
2952	xfs_inode_log_format_t	*in_f;
2953	xfs_mount_t		*mp = log->l_mp;
2954	xfs_buf_t		*bp;
2955	xfs_dinode_t		*dip;
2956	int			len;
2957	char			*src;
2958	char			*dest;
2959	int			error;
2960	int			attr_index;
2961	uint			fields;
2962	struct xfs_log_dinode	*ldip;
2963	uint			isize;
2964	int			need_free = 0;
2965
2966	if (item->ri_buf[0].i_len == sizeof(xfs_inode_log_format_t)) {
2967		in_f = item->ri_buf[0].i_addr;
2968	} else {
2969		in_f = kmem_alloc(sizeof(xfs_inode_log_format_t), KM_SLEEP);
2970		need_free = 1;
2971		error = xfs_inode_item_format_convert(&item->ri_buf[0], in_f);
2972		if (error)
2973			goto error;
2974	}
2975
2976	/*
2977	 * Inode buffers can be freed, look out for it,
2978	 * and do not replay the inode.
2979	 */
2980	if (xlog_check_buffer_cancelled(log, in_f->ilf_blkno,
2981					in_f->ilf_len, 0)) {
2982		error = 0;
2983		trace_xfs_log_recover_inode_cancel(log, in_f);
2984		goto error;
2985	}
2986	trace_xfs_log_recover_inode_recover(log, in_f);
2987
2988	bp = xfs_buf_read(mp->m_ddev_targp, in_f->ilf_blkno, in_f->ilf_len, 0,
2989			  &xfs_inode_buf_ops);
2990	if (!bp) {
2991		error = -ENOMEM;
2992		goto error;
2993	}
2994	error = bp->b_error;
2995	if (error) {
2996		xfs_buf_ioerror_alert(bp, "xlog_recover_do..(read#2)");
2997		goto out_release;
2998	}
2999	ASSERT(in_f->ilf_fields & XFS_ILOG_CORE);
3000	dip = xfs_buf_offset(bp, in_f->ilf_boffset);
3001
3002	/*
3003	 * Make sure the place we're flushing out to really looks
3004	 * like an inode!
3005	 */
3006	if (unlikely(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC))) {
3007		xfs_alert(mp,
3008	"%s: Bad inode magic number, dip = 0x%p, dino bp = 0x%p, ino = %Ld",
3009			__func__, dip, bp, in_f->ilf_ino);
3010		XFS_ERROR_REPORT("xlog_recover_inode_pass2(1)",
3011				 XFS_ERRLEVEL_LOW, mp);
3012		error = -EFSCORRUPTED;
3013		goto out_release;
3014	}
3015	ldip = item->ri_buf[1].i_addr;
3016	if (unlikely(ldip->di_magic != XFS_DINODE_MAGIC)) {
3017		xfs_alert(mp,
3018			"%s: Bad inode log record, rec ptr 0x%p, ino %Ld",
3019			__func__, item, in_f->ilf_ino);
3020		XFS_ERROR_REPORT("xlog_recover_inode_pass2(2)",
3021				 XFS_ERRLEVEL_LOW, mp);
3022		error = -EFSCORRUPTED;
3023		goto out_release;
3024	}
3025
3026	/*
3027	 * If the inode has an LSN in it, recover the inode only if it's less
3028	 * than the lsn of the transaction we are replaying. Note: we still
3029	 * need to replay an owner change even though the inode is more recent
3030	 * than the transaction as there is no guarantee that all the btree
3031	 * blocks are more recent than this transaction, too.
3032	 */
3033	if (dip->di_version >= 3) {
3034		xfs_lsn_t	lsn = be64_to_cpu(dip->di_lsn);
3035
3036		if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) {
3037			trace_xfs_log_recover_inode_skip(log, in_f);
3038			error = 0;
3039			goto out_owner_change;
3040		}
3041	}
3042
3043	/*
3044	 * di_flushiter is only valid for v1/2 inodes. All changes for v3 inodes
3045	 * are transactional and if ordering is necessary we can determine that
3046	 * more accurately by the LSN field in the V3 inode core. Don't trust
3047	 * the inode versions we might be changing them here - use the
3048	 * superblock flag to determine whether we need to look at di_flushiter
3049	 * to skip replay when the on disk inode is newer than the log one
3050	 */
3051	if (!xfs_sb_version_hascrc(&mp->m_sb) &&
3052	    ldip->di_flushiter < be16_to_cpu(dip->di_flushiter)) {
3053		/*
3054		 * Deal with the wrap case, DI_MAX_FLUSH is less
3055		 * than smaller numbers
3056		 */
3057		if (be16_to_cpu(dip->di_flushiter) == DI_MAX_FLUSH &&
3058		    ldip->di_flushiter < (DI_MAX_FLUSH >> 1)) {
3059			/* do nothing */
3060		} else {
3061			trace_xfs_log_recover_inode_skip(log, in_f);
3062			error = 0;
3063			goto out_release;
3064		}
3065	}
3066
3067	/* Take the opportunity to reset the flush iteration count */
3068	ldip->di_flushiter = 0;
3069
3070	if (unlikely(S_ISREG(ldip->di_mode))) {
3071		if ((ldip->di_format != XFS_DINODE_FMT_EXTENTS) &&
3072		    (ldip->di_format != XFS_DINODE_FMT_BTREE)) {
3073			XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(3)",
3074					 XFS_ERRLEVEL_LOW, mp, ldip);
3075			xfs_alert(mp,
3076		"%s: Bad regular inode log record, rec ptr 0x%p, "
3077		"ino ptr = 0x%p, ino bp = 0x%p, ino %Ld",
3078				__func__, item, dip, bp, in_f->ilf_ino);
3079			error = -EFSCORRUPTED;
3080			goto out_release;
3081		}
3082	} else if (unlikely(S_ISDIR(ldip->di_mode))) {
3083		if ((ldip->di_format != XFS_DINODE_FMT_EXTENTS) &&
3084		    (ldip->di_format != XFS_DINODE_FMT_BTREE) &&
3085		    (ldip->di_format != XFS_DINODE_FMT_LOCAL)) {
3086			XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(4)",
3087					     XFS_ERRLEVEL_LOW, mp, ldip);
3088			xfs_alert(mp,
3089		"%s: Bad dir inode log record, rec ptr 0x%p, "
3090		"ino ptr = 0x%p, ino bp = 0x%p, ino %Ld",
3091				__func__, item, dip, bp, in_f->ilf_ino);
3092			error = -EFSCORRUPTED;
3093			goto out_release;
3094		}
3095	}
3096	if (unlikely(ldip->di_nextents + ldip->di_anextents > ldip->di_nblocks)){
3097		XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(5)",
3098				     XFS_ERRLEVEL_LOW, mp, ldip);
3099		xfs_alert(mp,
3100	"%s: Bad inode log record, rec ptr 0x%p, dino ptr 0x%p, "
3101	"dino bp 0x%p, ino %Ld, total extents = %d, nblocks = %Ld",
3102			__func__, item, dip, bp, in_f->ilf_ino,
3103			ldip->di_nextents + ldip->di_anextents,
3104			ldip->di_nblocks);
3105		error = -EFSCORRUPTED;
3106		goto out_release;
3107	}
3108	if (unlikely(ldip->di_forkoff > mp->m_sb.sb_inodesize)) {
3109		XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(6)",
3110				     XFS_ERRLEVEL_LOW, mp, ldip);
3111		xfs_alert(mp,
3112	"%s: Bad inode log record, rec ptr 0x%p, dino ptr 0x%p, "
3113	"dino bp 0x%p, ino %Ld, forkoff 0x%x", __func__,
3114			item, dip, bp, in_f->ilf_ino, ldip->di_forkoff);
3115		error = -EFSCORRUPTED;
3116		goto out_release;
3117	}
3118	isize = xfs_log_dinode_size(ldip->di_version);
3119	if (unlikely(item->ri_buf[1].i_len > isize)) {
3120		XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(7)",
3121				     XFS_ERRLEVEL_LOW, mp, ldip);
3122		xfs_alert(mp,
3123			"%s: Bad inode log record length %d, rec ptr 0x%p",
3124			__func__, item->ri_buf[1].i_len, item);
3125		error = -EFSCORRUPTED;
3126		goto out_release;
3127	}
3128
3129	/* recover the log dinode inode into the on disk inode */
3130	xfs_log_dinode_to_disk(ldip, dip);
3131
3132	/* the rest is in on-disk format */
3133	if (item->ri_buf[1].i_len > isize) {
3134		memcpy((char *)dip + isize,
3135			item->ri_buf[1].i_addr + isize,
3136			item->ri_buf[1].i_len - isize);
3137	}
3138
3139	fields = in_f->ilf_fields;
3140	switch (fields & (XFS_ILOG_DEV | XFS_ILOG_UUID)) {
3141	case XFS_ILOG_DEV:
3142		xfs_dinode_put_rdev(dip, in_f->ilf_u.ilfu_rdev);
3143		break;
3144	case XFS_ILOG_UUID:
3145		memcpy(XFS_DFORK_DPTR(dip),
3146		       &in_f->ilf_u.ilfu_uuid,
3147		       sizeof(uuid_t));
3148		break;
3149	}
3150
3151	if (in_f->ilf_size == 2)
3152		goto out_owner_change;
3153	len = item->ri_buf[2].i_len;
3154	src = item->ri_buf[2].i_addr;
3155	ASSERT(in_f->ilf_size <= 4);
3156	ASSERT((in_f->ilf_size == 3) || (fields & XFS_ILOG_AFORK));
3157	ASSERT(!(fields & XFS_ILOG_DFORK) ||
3158	       (len == in_f->ilf_dsize));
3159
3160	switch (fields & XFS_ILOG_DFORK) {
3161	case XFS_ILOG_DDATA:
3162	case XFS_ILOG_DEXT:
3163		memcpy(XFS_DFORK_DPTR(dip), src, len);
3164		break;
3165
3166	case XFS_ILOG_DBROOT:
3167		xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src, len,
3168				 (xfs_bmdr_block_t *)XFS_DFORK_DPTR(dip),
3169				 XFS_DFORK_DSIZE(dip, mp));
3170		break;
3171
3172	default:
3173		/*
3174		 * There are no data fork flags set.
3175		 */
3176		ASSERT((fields & XFS_ILOG_DFORK) == 0);
3177		break;
3178	}
3179
3180	/*
3181	 * If we logged any attribute data, recover it.  There may or
3182	 * may not have been any other non-core data logged in this
3183	 * transaction.
3184	 */
3185	if (in_f->ilf_fields & XFS_ILOG_AFORK) {
3186		if (in_f->ilf_fields & XFS_ILOG_DFORK) {
3187			attr_index = 3;
3188		} else {
3189			attr_index = 2;
3190		}
3191		len = item->ri_buf[attr_index].i_len;
3192		src = item->ri_buf[attr_index].i_addr;
3193		ASSERT(len == in_f->ilf_asize);
3194
3195		switch (in_f->ilf_fields & XFS_ILOG_AFORK) {
3196		case XFS_ILOG_ADATA:
3197		case XFS_ILOG_AEXT:
3198			dest = XFS_DFORK_APTR(dip);
3199			ASSERT(len <= XFS_DFORK_ASIZE(dip, mp));
3200			memcpy(dest, src, len);
3201			break;
3202
3203		case XFS_ILOG_ABROOT:
3204			dest = XFS_DFORK_APTR(dip);
3205			xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src,
3206					 len, (xfs_bmdr_block_t*)dest,
3207					 XFS_DFORK_ASIZE(dip, mp));
3208			break;
3209
3210		default:
3211			xfs_warn(log->l_mp, "%s: Invalid flag", __func__);
3212			ASSERT(0);
3213			error = -EIO;
3214			goto out_release;
3215		}
3216	}
3217
3218out_owner_change:
3219	if (in_f->ilf_fields & (XFS_ILOG_DOWNER|XFS_ILOG_AOWNER))
 
 
3220		error = xfs_recover_inode_owner_change(mp, dip, in_f,
3221						       buffer_list);
3222	/* re-generate the checksum. */
3223	xfs_dinode_calc_crc(log->l_mp, dip);
3224
3225	ASSERT(bp->b_target->bt_mount == mp);
3226	bp->b_iodone = xlog_recover_iodone;
3227	xfs_buf_delwri_queue(bp, buffer_list);
3228
3229out_release:
3230	xfs_buf_relse(bp);
3231error:
3232	if (need_free)
3233		kmem_free(in_f);
3234	return error;
3235}
3236
3237/*
3238 * Recover QUOTAOFF records. We simply make a note of it in the xlog
3239 * structure, so that we know not to do any dquot item or dquot buffer recovery,
3240 * of that type.
3241 */
3242STATIC int
3243xlog_recover_quotaoff_pass1(
3244	struct xlog			*log,
3245	struct xlog_recover_item	*item)
3246{
3247	xfs_qoff_logformat_t	*qoff_f = item->ri_buf[0].i_addr;
3248	ASSERT(qoff_f);
3249
3250	/*
3251	 * The logitem format's flag tells us if this was user quotaoff,
3252	 * group/project quotaoff or both.
3253	 */
3254	if (qoff_f->qf_flags & XFS_UQUOTA_ACCT)
3255		log->l_quotaoffs_flag |= XFS_DQ_USER;
3256	if (qoff_f->qf_flags & XFS_PQUOTA_ACCT)
3257		log->l_quotaoffs_flag |= XFS_DQ_PROJ;
3258	if (qoff_f->qf_flags & XFS_GQUOTA_ACCT)
3259		log->l_quotaoffs_flag |= XFS_DQ_GROUP;
3260
3261	return 0;
3262}
3263
3264/*
3265 * Recover a dquot record
3266 */
3267STATIC int
3268xlog_recover_dquot_pass2(
3269	struct xlog			*log,
3270	struct list_head		*buffer_list,
3271	struct xlog_recover_item	*item,
3272	xfs_lsn_t			current_lsn)
3273{
3274	xfs_mount_t		*mp = log->l_mp;
3275	xfs_buf_t		*bp;
3276	struct xfs_disk_dquot	*ddq, *recddq;
 
3277	int			error;
3278	xfs_dq_logformat_t	*dq_f;
3279	uint			type;
3280
3281
3282	/*
3283	 * Filesystems are required to send in quota flags at mount time.
3284	 */
3285	if (mp->m_qflags == 0)
3286		return 0;
3287
3288	recddq = item->ri_buf[1].i_addr;
3289	if (recddq == NULL) {
3290		xfs_alert(log->l_mp, "NULL dquot in %s.", __func__);
3291		return -EIO;
3292	}
3293	if (item->ri_buf[1].i_len < sizeof(xfs_disk_dquot_t)) {
3294		xfs_alert(log->l_mp, "dquot too small (%d) in %s.",
3295			item->ri_buf[1].i_len, __func__);
3296		return -EIO;
3297	}
3298
3299	/*
3300	 * This type of quotas was turned off, so ignore this record.
3301	 */
3302	type = recddq->d_flags & (XFS_DQ_USER | XFS_DQ_PROJ | XFS_DQ_GROUP);
3303	ASSERT(type);
3304	if (log->l_quotaoffs_flag & type)
3305		return 0;
3306
3307	/*
3308	 * At this point we know that quota was _not_ turned off.
3309	 * Since the mount flags are not indicating to us otherwise, this
3310	 * must mean that quota is on, and the dquot needs to be replayed.
3311	 * Remember that we may not have fully recovered the superblock yet,
3312	 * so we can't do the usual trick of looking at the SB quota bits.
3313	 *
3314	 * The other possibility, of course, is that the quota subsystem was
3315	 * removed since the last mount - ENOSYS.
3316	 */
3317	dq_f = item->ri_buf[0].i_addr;
3318	ASSERT(dq_f);
3319	error = xfs_dqcheck(mp, recddq, dq_f->qlf_id, 0, XFS_QMOPT_DOWARN,
3320			   "xlog_recover_dquot_pass2 (log copy)");
3321	if (error)
 
3322		return -EIO;
 
3323	ASSERT(dq_f->qlf_len == 1);
3324
3325	/*
3326	 * At this point we are assuming that the dquots have been allocated
3327	 * and hence the buffer has valid dquots stamped in it. It should,
3328	 * therefore, pass verifier validation. If the dquot is bad, then the
3329	 * we'll return an error here, so we don't need to specifically check
3330	 * the dquot in the buffer after the verifier has run.
3331	 */
3332	error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dq_f->qlf_blkno,
3333				   XFS_FSB_TO_BB(mp, dq_f->qlf_len), 0, &bp,
3334				   &xfs_dquot_buf_ops);
3335	if (error)
3336		return error;
3337
3338	ASSERT(bp);
3339	ddq = xfs_buf_offset(bp, dq_f->qlf_boffset);
3340
3341	/*
3342	 * If the dquot has an LSN in it, recover the dquot only if it's less
3343	 * than the lsn of the transaction we are replaying.
3344	 */
3345	if (xfs_sb_version_hascrc(&mp->m_sb)) {
3346		struct xfs_dqblk *dqb = (struct xfs_dqblk *)ddq;
3347		xfs_lsn_t	lsn = be64_to_cpu(dqb->dd_lsn);
3348
3349		if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) {
3350			goto out_release;
3351		}
3352	}
3353
3354	memcpy(ddq, recddq, item->ri_buf[1].i_len);
3355	if (xfs_sb_version_hascrc(&mp->m_sb)) {
3356		xfs_update_cksum((char *)ddq, sizeof(struct xfs_dqblk),
3357				 XFS_DQUOT_CRC_OFF);
3358	}
3359
3360	ASSERT(dq_f->qlf_size == 2);
3361	ASSERT(bp->b_target->bt_mount == mp);
3362	bp->b_iodone = xlog_recover_iodone;
3363	xfs_buf_delwri_queue(bp, buffer_list);
3364
3365out_release:
3366	xfs_buf_relse(bp);
3367	return 0;
3368}
3369
3370/*
3371 * This routine is called to create an in-core extent free intent
3372 * item from the efi format structure which was logged on disk.
3373 * It allocates an in-core efi, copies the extents from the format
3374 * structure into it, and adds the efi to the AIL with the given
3375 * LSN.
3376 */
3377STATIC int
3378xlog_recover_efi_pass2(
3379	struct xlog			*log,
3380	struct xlog_recover_item	*item,
3381	xfs_lsn_t			lsn)
3382{
3383	int				error;
3384	struct xfs_mount		*mp = log->l_mp;
3385	struct xfs_efi_log_item		*efip;
3386	struct xfs_efi_log_format	*efi_formatp;
3387
3388	efi_formatp = item->ri_buf[0].i_addr;
3389
3390	efip = xfs_efi_init(mp, efi_formatp->efi_nextents);
3391	error = xfs_efi_copy_format(&item->ri_buf[0], &efip->efi_format);
3392	if (error) {
3393		xfs_efi_item_free(efip);
3394		return error;
3395	}
3396	atomic_set(&efip->efi_next_extent, efi_formatp->efi_nextents);
3397
3398	spin_lock(&log->l_ailp->xa_lock);
3399	/*
3400	 * The EFI has two references. One for the EFD and one for EFI to ensure
3401	 * it makes it into the AIL. Insert the EFI into the AIL directly and
3402	 * drop the EFI reference. Note that xfs_trans_ail_update() drops the
3403	 * AIL lock.
3404	 */
3405	xfs_trans_ail_update(log->l_ailp, &efip->efi_item, lsn);
3406	xfs_efi_release(efip);
3407	return 0;
3408}
3409
3410
3411/*
3412 * This routine is called when an EFD format structure is found in a committed
3413 * transaction in the log. Its purpose is to cancel the corresponding EFI if it
3414 * was still in the log. To do this it searches the AIL for the EFI with an id
3415 * equal to that in the EFD format structure. If we find it we drop the EFD
3416 * reference, which removes the EFI from the AIL and frees it.
3417 */
3418STATIC int
3419xlog_recover_efd_pass2(
3420	struct xlog			*log,
3421	struct xlog_recover_item	*item)
3422{
3423	xfs_efd_log_format_t	*efd_formatp;
3424	xfs_efi_log_item_t	*efip = NULL;
3425	xfs_log_item_t		*lip;
3426	__uint64_t		efi_id;
3427	struct xfs_ail_cursor	cur;
3428	struct xfs_ail		*ailp = log->l_ailp;
3429
3430	efd_formatp = item->ri_buf[0].i_addr;
3431	ASSERT((item->ri_buf[0].i_len == (sizeof(xfs_efd_log_format_32_t) +
3432		((efd_formatp->efd_nextents - 1) * sizeof(xfs_extent_32_t)))) ||
3433	       (item->ri_buf[0].i_len == (sizeof(xfs_efd_log_format_64_t) +
3434		((efd_formatp->efd_nextents - 1) * sizeof(xfs_extent_64_t)))));
3435	efi_id = efd_formatp->efd_efi_id;
3436
3437	/*
3438	 * Search for the EFI with the id in the EFD format structure in the
3439	 * AIL.
3440	 */
3441	spin_lock(&ailp->xa_lock);
3442	lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3443	while (lip != NULL) {
3444		if (lip->li_type == XFS_LI_EFI) {
3445			efip = (xfs_efi_log_item_t *)lip;
3446			if (efip->efi_format.efi_id == efi_id) {
3447				/*
3448				 * Drop the EFD reference to the EFI. This
3449				 * removes the EFI from the AIL and frees it.
3450				 */
3451				spin_unlock(&ailp->xa_lock);
3452				xfs_efi_release(efip);
3453				spin_lock(&ailp->xa_lock);
3454				break;
3455			}
3456		}
3457		lip = xfs_trans_ail_cursor_next(ailp, &cur);
3458	}
3459
3460	xfs_trans_ail_cursor_done(&cur);
3461	spin_unlock(&ailp->xa_lock);
3462
3463	return 0;
3464}
3465
3466/*
3467 * This routine is called to create an in-core extent rmap update
3468 * item from the rui format structure which was logged on disk.
3469 * It allocates an in-core rui, copies the extents from the format
3470 * structure into it, and adds the rui to the AIL with the given
3471 * LSN.
3472 */
3473STATIC int
3474xlog_recover_rui_pass2(
3475	struct xlog			*log,
3476	struct xlog_recover_item	*item,
3477	xfs_lsn_t			lsn)
3478{
3479	int				error;
3480	struct xfs_mount		*mp = log->l_mp;
3481	struct xfs_rui_log_item		*ruip;
3482	struct xfs_rui_log_format	*rui_formatp;
3483
3484	rui_formatp = item->ri_buf[0].i_addr;
3485
3486	ruip = xfs_rui_init(mp, rui_formatp->rui_nextents);
3487	error = xfs_rui_copy_format(&item->ri_buf[0], &ruip->rui_format);
3488	if (error) {
3489		xfs_rui_item_free(ruip);
3490		return error;
3491	}
3492	atomic_set(&ruip->rui_next_extent, rui_formatp->rui_nextents);
3493
3494	spin_lock(&log->l_ailp->xa_lock);
3495	/*
3496	 * The RUI has two references. One for the RUD and one for RUI to ensure
3497	 * it makes it into the AIL. Insert the RUI into the AIL directly and
3498	 * drop the RUI reference. Note that xfs_trans_ail_update() drops the
3499	 * AIL lock.
3500	 */
3501	xfs_trans_ail_update(log->l_ailp, &ruip->rui_item, lsn);
3502	xfs_rui_release(ruip);
3503	return 0;
3504}
3505
3506
3507/*
3508 * This routine is called when an RUD format structure is found in a committed
3509 * transaction in the log. Its purpose is to cancel the corresponding RUI if it
3510 * was still in the log. To do this it searches the AIL for the RUI with an id
3511 * equal to that in the RUD format structure. If we find it we drop the RUD
3512 * reference, which removes the RUI from the AIL and frees it.
3513 */
3514STATIC int
3515xlog_recover_rud_pass2(
3516	struct xlog			*log,
3517	struct xlog_recover_item	*item)
3518{
3519	struct xfs_rud_log_format	*rud_formatp;
3520	struct xfs_rui_log_item		*ruip = NULL;
3521	struct xfs_log_item		*lip;
3522	__uint64_t			rui_id;
3523	struct xfs_ail_cursor		cur;
3524	struct xfs_ail			*ailp = log->l_ailp;
3525
3526	rud_formatp = item->ri_buf[0].i_addr;
3527	ASSERT(item->ri_buf[0].i_len == sizeof(struct xfs_rud_log_format));
3528	rui_id = rud_formatp->rud_rui_id;
3529
3530	/*
3531	 * Search for the RUI with the id in the RUD format structure in the
3532	 * AIL.
3533	 */
3534	spin_lock(&ailp->xa_lock);
3535	lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3536	while (lip != NULL) {
3537		if (lip->li_type == XFS_LI_RUI) {
3538			ruip = (struct xfs_rui_log_item *)lip;
3539			if (ruip->rui_format.rui_id == rui_id) {
3540				/*
3541				 * Drop the RUD reference to the RUI. This
3542				 * removes the RUI from the AIL and frees it.
3543				 */
3544				spin_unlock(&ailp->xa_lock);
3545				xfs_rui_release(ruip);
3546				spin_lock(&ailp->xa_lock);
3547				break;
3548			}
3549		}
3550		lip = xfs_trans_ail_cursor_next(ailp, &cur);
3551	}
3552
3553	xfs_trans_ail_cursor_done(&cur);
3554	spin_unlock(&ailp->xa_lock);
3555
3556	return 0;
3557}
3558
3559/*
3560 * Copy an CUI format buffer from the given buf, and into the destination
3561 * CUI format structure.  The CUI/CUD items were designed not to need any
3562 * special alignment handling.
3563 */
3564static int
3565xfs_cui_copy_format(
3566	struct xfs_log_iovec		*buf,
3567	struct xfs_cui_log_format	*dst_cui_fmt)
3568{
3569	struct xfs_cui_log_format	*src_cui_fmt;
3570	uint				len;
3571
3572	src_cui_fmt = buf->i_addr;
3573	len = xfs_cui_log_format_sizeof(src_cui_fmt->cui_nextents);
3574
3575	if (buf->i_len == len) {
3576		memcpy(dst_cui_fmt, src_cui_fmt, len);
3577		return 0;
3578	}
3579	return -EFSCORRUPTED;
3580}
3581
3582/*
3583 * This routine is called to create an in-core extent refcount update
3584 * item from the cui format structure which was logged on disk.
3585 * It allocates an in-core cui, copies the extents from the format
3586 * structure into it, and adds the cui to the AIL with the given
3587 * LSN.
3588 */
3589STATIC int
3590xlog_recover_cui_pass2(
3591	struct xlog			*log,
3592	struct xlog_recover_item	*item,
3593	xfs_lsn_t			lsn)
3594{
3595	int				error;
3596	struct xfs_mount		*mp = log->l_mp;
3597	struct xfs_cui_log_item		*cuip;
3598	struct xfs_cui_log_format	*cui_formatp;
3599
3600	cui_formatp = item->ri_buf[0].i_addr;
3601
3602	cuip = xfs_cui_init(mp, cui_formatp->cui_nextents);
3603	error = xfs_cui_copy_format(&item->ri_buf[0], &cuip->cui_format);
3604	if (error) {
3605		xfs_cui_item_free(cuip);
3606		return error;
3607	}
3608	atomic_set(&cuip->cui_next_extent, cui_formatp->cui_nextents);
3609
3610	spin_lock(&log->l_ailp->xa_lock);
3611	/*
3612	 * The CUI has two references. One for the CUD and one for CUI to ensure
3613	 * it makes it into the AIL. Insert the CUI into the AIL directly and
3614	 * drop the CUI reference. Note that xfs_trans_ail_update() drops the
3615	 * AIL lock.
3616	 */
3617	xfs_trans_ail_update(log->l_ailp, &cuip->cui_item, lsn);
3618	xfs_cui_release(cuip);
3619	return 0;
3620}
3621
3622
3623/*
3624 * This routine is called when an CUD format structure is found in a committed
3625 * transaction in the log. Its purpose is to cancel the corresponding CUI if it
3626 * was still in the log. To do this it searches the AIL for the CUI with an id
3627 * equal to that in the CUD format structure. If we find it we drop the CUD
3628 * reference, which removes the CUI from the AIL and frees it.
3629 */
3630STATIC int
3631xlog_recover_cud_pass2(
3632	struct xlog			*log,
3633	struct xlog_recover_item	*item)
3634{
3635	struct xfs_cud_log_format	*cud_formatp;
3636	struct xfs_cui_log_item		*cuip = NULL;
3637	struct xfs_log_item		*lip;
3638	__uint64_t			cui_id;
3639	struct xfs_ail_cursor		cur;
3640	struct xfs_ail			*ailp = log->l_ailp;
3641
3642	cud_formatp = item->ri_buf[0].i_addr;
3643	if (item->ri_buf[0].i_len != sizeof(struct xfs_cud_log_format))
3644		return -EFSCORRUPTED;
3645	cui_id = cud_formatp->cud_cui_id;
3646
3647	/*
3648	 * Search for the CUI with the id in the CUD format structure in the
3649	 * AIL.
3650	 */
3651	spin_lock(&ailp->xa_lock);
3652	lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3653	while (lip != NULL) {
3654		if (lip->li_type == XFS_LI_CUI) {
3655			cuip = (struct xfs_cui_log_item *)lip;
3656			if (cuip->cui_format.cui_id == cui_id) {
3657				/*
3658				 * Drop the CUD reference to the CUI. This
3659				 * removes the CUI from the AIL and frees it.
3660				 */
3661				spin_unlock(&ailp->xa_lock);
3662				xfs_cui_release(cuip);
3663				spin_lock(&ailp->xa_lock);
3664				break;
3665			}
3666		}
3667		lip = xfs_trans_ail_cursor_next(ailp, &cur);
3668	}
3669
3670	xfs_trans_ail_cursor_done(&cur);
3671	spin_unlock(&ailp->xa_lock);
3672
3673	return 0;
3674}
3675
3676/*
3677 * Copy an BUI format buffer from the given buf, and into the destination
3678 * BUI format structure.  The BUI/BUD items were designed not to need any
3679 * special alignment handling.
3680 */
3681static int
3682xfs_bui_copy_format(
3683	struct xfs_log_iovec		*buf,
3684	struct xfs_bui_log_format	*dst_bui_fmt)
3685{
3686	struct xfs_bui_log_format	*src_bui_fmt;
3687	uint				len;
3688
3689	src_bui_fmt = buf->i_addr;
3690	len = xfs_bui_log_format_sizeof(src_bui_fmt->bui_nextents);
3691
3692	if (buf->i_len == len) {
3693		memcpy(dst_bui_fmt, src_bui_fmt, len);
3694		return 0;
3695	}
3696	return -EFSCORRUPTED;
3697}
3698
3699/*
3700 * This routine is called to create an in-core extent bmap update
3701 * item from the bui format structure which was logged on disk.
3702 * It allocates an in-core bui, copies the extents from the format
3703 * structure into it, and adds the bui to the AIL with the given
3704 * LSN.
3705 */
3706STATIC int
3707xlog_recover_bui_pass2(
3708	struct xlog			*log,
3709	struct xlog_recover_item	*item,
3710	xfs_lsn_t			lsn)
3711{
3712	int				error;
3713	struct xfs_mount		*mp = log->l_mp;
3714	struct xfs_bui_log_item		*buip;
3715	struct xfs_bui_log_format	*bui_formatp;
3716
3717	bui_formatp = item->ri_buf[0].i_addr;
3718
3719	if (bui_formatp->bui_nextents != XFS_BUI_MAX_FAST_EXTENTS)
3720		return -EFSCORRUPTED;
3721	buip = xfs_bui_init(mp);
3722	error = xfs_bui_copy_format(&item->ri_buf[0], &buip->bui_format);
3723	if (error) {
3724		xfs_bui_item_free(buip);
3725		return error;
3726	}
3727	atomic_set(&buip->bui_next_extent, bui_formatp->bui_nextents);
3728
3729	spin_lock(&log->l_ailp->xa_lock);
3730	/*
3731	 * The RUI has two references. One for the RUD and one for RUI to ensure
3732	 * it makes it into the AIL. Insert the RUI into the AIL directly and
3733	 * drop the RUI reference. Note that xfs_trans_ail_update() drops the
3734	 * AIL lock.
3735	 */
3736	xfs_trans_ail_update(log->l_ailp, &buip->bui_item, lsn);
3737	xfs_bui_release(buip);
3738	return 0;
3739}
3740
3741
3742/*
3743 * This routine is called when an BUD format structure is found in a committed
3744 * transaction in the log. Its purpose is to cancel the corresponding BUI if it
3745 * was still in the log. To do this it searches the AIL for the BUI with an id
3746 * equal to that in the BUD format structure. If we find it we drop the BUD
3747 * reference, which removes the BUI from the AIL and frees it.
3748 */
3749STATIC int
3750xlog_recover_bud_pass2(
3751	struct xlog			*log,
3752	struct xlog_recover_item	*item)
3753{
3754	struct xfs_bud_log_format	*bud_formatp;
3755	struct xfs_bui_log_item		*buip = NULL;
3756	struct xfs_log_item		*lip;
3757	__uint64_t			bui_id;
3758	struct xfs_ail_cursor		cur;
3759	struct xfs_ail			*ailp = log->l_ailp;
3760
3761	bud_formatp = item->ri_buf[0].i_addr;
3762	if (item->ri_buf[0].i_len != sizeof(struct xfs_bud_log_format))
3763		return -EFSCORRUPTED;
3764	bui_id = bud_formatp->bud_bui_id;
3765
3766	/*
3767	 * Search for the BUI with the id in the BUD format structure in the
3768	 * AIL.
3769	 */
3770	spin_lock(&ailp->xa_lock);
3771	lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3772	while (lip != NULL) {
3773		if (lip->li_type == XFS_LI_BUI) {
3774			buip = (struct xfs_bui_log_item *)lip;
3775			if (buip->bui_format.bui_id == bui_id) {
3776				/*
3777				 * Drop the BUD reference to the BUI. This
3778				 * removes the BUI from the AIL and frees it.
3779				 */
3780				spin_unlock(&ailp->xa_lock);
3781				xfs_bui_release(buip);
3782				spin_lock(&ailp->xa_lock);
3783				break;
3784			}
3785		}
3786		lip = xfs_trans_ail_cursor_next(ailp, &cur);
3787	}
3788
3789	xfs_trans_ail_cursor_done(&cur);
3790	spin_unlock(&ailp->xa_lock);
3791
3792	return 0;
3793}
3794
3795/*
3796 * This routine is called when an inode create format structure is found in a
3797 * committed transaction in the log.  It's purpose is to initialise the inodes
3798 * being allocated on disk. This requires us to get inode cluster buffers that
3799 * match the range to be intialised, stamped with inode templates and written
3800 * by delayed write so that subsequent modifications will hit the cached buffer
3801 * and only need writing out at the end of recovery.
3802 */
3803STATIC int
3804xlog_recover_do_icreate_pass2(
3805	struct xlog		*log,
3806	struct list_head	*buffer_list,
3807	xlog_recover_item_t	*item)
3808{
3809	struct xfs_mount	*mp = log->l_mp;
3810	struct xfs_icreate_log	*icl;
3811	xfs_agnumber_t		agno;
3812	xfs_agblock_t		agbno;
3813	unsigned int		count;
3814	unsigned int		isize;
3815	xfs_agblock_t		length;
3816	int			blks_per_cluster;
3817	int			bb_per_cluster;
3818	int			cancel_count;
3819	int			nbufs;
3820	int			i;
3821
3822	icl = (struct xfs_icreate_log *)item->ri_buf[0].i_addr;
3823	if (icl->icl_type != XFS_LI_ICREATE) {
3824		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad type");
3825		return -EINVAL;
3826	}
3827
3828	if (icl->icl_size != 1) {
3829		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad icl size");
3830		return -EINVAL;
3831	}
3832
3833	agno = be32_to_cpu(icl->icl_ag);
3834	if (agno >= mp->m_sb.sb_agcount) {
3835		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad agno");
3836		return -EINVAL;
3837	}
3838	agbno = be32_to_cpu(icl->icl_agbno);
3839	if (!agbno || agbno == NULLAGBLOCK || agbno >= mp->m_sb.sb_agblocks) {
3840		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad agbno");
3841		return -EINVAL;
3842	}
3843	isize = be32_to_cpu(icl->icl_isize);
3844	if (isize != mp->m_sb.sb_inodesize) {
3845		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad isize");
3846		return -EINVAL;
3847	}
3848	count = be32_to_cpu(icl->icl_count);
3849	if (!count) {
3850		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad count");
3851		return -EINVAL;
3852	}
3853	length = be32_to_cpu(icl->icl_length);
3854	if (!length || length >= mp->m_sb.sb_agblocks) {
3855		xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad length");
3856		return -EINVAL;
3857	}
3858
3859	/*
3860	 * The inode chunk is either full or sparse and we only support
3861	 * m_ialloc_min_blks sized sparse allocations at this time.
3862	 */
3863	if (length != mp->m_ialloc_blks &&
3864	    length != mp->m_ialloc_min_blks) {
3865		xfs_warn(log->l_mp,
3866			 "%s: unsupported chunk length", __FUNCTION__);
3867		return -EINVAL;
3868	}
3869
3870	/* verify inode count is consistent with extent length */
3871	if ((count >> mp->m_sb.sb_inopblog) != length) {
3872		xfs_warn(log->l_mp,
3873			 "%s: inconsistent inode count and chunk length",
3874			 __FUNCTION__);
3875		return -EINVAL;
3876	}
3877
3878	/*
3879	 * The icreate transaction can cover multiple cluster buffers and these
3880	 * buffers could have been freed and reused. Check the individual
3881	 * buffers for cancellation so we don't overwrite anything written after
3882	 * a cancellation.
3883	 */
3884	blks_per_cluster = xfs_icluster_size_fsb(mp);
3885	bb_per_cluster = XFS_FSB_TO_BB(mp, blks_per_cluster);
3886	nbufs = length / blks_per_cluster;
3887	for (i = 0, cancel_count = 0; i < nbufs; i++) {
3888		xfs_daddr_t	daddr;
3889
3890		daddr = XFS_AGB_TO_DADDR(mp, agno,
3891					 agbno + i * blks_per_cluster);
3892		if (xlog_check_buffer_cancelled(log, daddr, bb_per_cluster, 0))
3893			cancel_count++;
3894	}
3895
3896	/*
3897	 * We currently only use icreate for a single allocation at a time. This
3898	 * means we should expect either all or none of the buffers to be
3899	 * cancelled. Be conservative and skip replay if at least one buffer is
3900	 * cancelled, but warn the user that something is awry if the buffers
3901	 * are not consistent.
3902	 *
3903	 * XXX: This must be refined to only skip cancelled clusters once we use
3904	 * icreate for multiple chunk allocations.
3905	 */
3906	ASSERT(!cancel_count || cancel_count == nbufs);
3907	if (cancel_count) {
3908		if (cancel_count != nbufs)
3909			xfs_warn(mp,
3910	"WARNING: partial inode chunk cancellation, skipped icreate.");
3911		trace_xfs_log_recover_icreate_cancel(log, icl);
3912		return 0;
3913	}
3914
3915	trace_xfs_log_recover_icreate_recover(log, icl);
3916	return xfs_ialloc_inode_init(mp, NULL, buffer_list, count, agno, agbno,
3917				     length, be32_to_cpu(icl->icl_gen));
3918}
3919
3920STATIC void
3921xlog_recover_buffer_ra_pass2(
3922	struct xlog                     *log,
3923	struct xlog_recover_item        *item)
3924{
3925	struct xfs_buf_log_format	*buf_f = item->ri_buf[0].i_addr;
3926	struct xfs_mount		*mp = log->l_mp;
3927
3928	if (xlog_peek_buffer_cancelled(log, buf_f->blf_blkno,
3929			buf_f->blf_len, buf_f->blf_flags)) {
3930		return;
3931	}
3932
3933	xfs_buf_readahead(mp->m_ddev_targp, buf_f->blf_blkno,
3934				buf_f->blf_len, NULL);
3935}
3936
3937STATIC void
3938xlog_recover_inode_ra_pass2(
3939	struct xlog                     *log,
3940	struct xlog_recover_item        *item)
3941{
3942	struct xfs_inode_log_format	ilf_buf;
3943	struct xfs_inode_log_format	*ilfp;
3944	struct xfs_mount		*mp = log->l_mp;
3945	int			error;
3946
3947	if (item->ri_buf[0].i_len == sizeof(struct xfs_inode_log_format)) {
3948		ilfp = item->ri_buf[0].i_addr;
3949	} else {
3950		ilfp = &ilf_buf;
3951		memset(ilfp, 0, sizeof(*ilfp));
3952		error = xfs_inode_item_format_convert(&item->ri_buf[0], ilfp);
3953		if (error)
3954			return;
3955	}
3956
3957	if (xlog_peek_buffer_cancelled(log, ilfp->ilf_blkno, ilfp->ilf_len, 0))
3958		return;
3959
3960	xfs_buf_readahead(mp->m_ddev_targp, ilfp->ilf_blkno,
3961				ilfp->ilf_len, &xfs_inode_buf_ra_ops);
3962}
3963
3964STATIC void
3965xlog_recover_dquot_ra_pass2(
3966	struct xlog			*log,
3967	struct xlog_recover_item	*item)
3968{
3969	struct xfs_mount	*mp = log->l_mp;
3970	struct xfs_disk_dquot	*recddq;
3971	struct xfs_dq_logformat	*dq_f;
3972	uint			type;
3973	int			len;
3974
3975
3976	if (mp->m_qflags == 0)
3977		return;
3978
3979	recddq = item->ri_buf[1].i_addr;
3980	if (recddq == NULL)
3981		return;
3982	if (item->ri_buf[1].i_len < sizeof(struct xfs_disk_dquot))
3983		return;
3984
3985	type = recddq->d_flags & (XFS_DQ_USER | XFS_DQ_PROJ | XFS_DQ_GROUP);
3986	ASSERT(type);
3987	if (log->l_quotaoffs_flag & type)
3988		return;
3989
3990	dq_f = item->ri_buf[0].i_addr;
3991	ASSERT(dq_f);
3992	ASSERT(dq_f->qlf_len == 1);
3993
3994	len = XFS_FSB_TO_BB(mp, dq_f->qlf_len);
3995	if (xlog_peek_buffer_cancelled(log, dq_f->qlf_blkno, len, 0))
3996		return;
3997
3998	xfs_buf_readahead(mp->m_ddev_targp, dq_f->qlf_blkno, len,
3999			  &xfs_dquot_buf_ra_ops);
4000}
4001
4002STATIC void
4003xlog_recover_ra_pass2(
4004	struct xlog			*log,
4005	struct xlog_recover_item	*item)
4006{
4007	switch (ITEM_TYPE(item)) {
4008	case XFS_LI_BUF:
4009		xlog_recover_buffer_ra_pass2(log, item);
4010		break;
4011	case XFS_LI_INODE:
4012		xlog_recover_inode_ra_pass2(log, item);
4013		break;
4014	case XFS_LI_DQUOT:
4015		xlog_recover_dquot_ra_pass2(log, item);
4016		break;
4017	case XFS_LI_EFI:
4018	case XFS_LI_EFD:
4019	case XFS_LI_QUOTAOFF:
4020	case XFS_LI_RUI:
4021	case XFS_LI_RUD:
4022	case XFS_LI_CUI:
4023	case XFS_LI_CUD:
4024	case XFS_LI_BUI:
4025	case XFS_LI_BUD:
4026	default:
4027		break;
4028	}
4029}
4030
4031STATIC int
4032xlog_recover_commit_pass1(
4033	struct xlog			*log,
4034	struct xlog_recover		*trans,
4035	struct xlog_recover_item	*item)
4036{
4037	trace_xfs_log_recover_item_recover(log, trans, item, XLOG_RECOVER_PASS1);
4038
4039	switch (ITEM_TYPE(item)) {
4040	case XFS_LI_BUF:
4041		return xlog_recover_buffer_pass1(log, item);
4042	case XFS_LI_QUOTAOFF:
4043		return xlog_recover_quotaoff_pass1(log, item);
4044	case XFS_LI_INODE:
4045	case XFS_LI_EFI:
4046	case XFS_LI_EFD:
4047	case XFS_LI_DQUOT:
4048	case XFS_LI_ICREATE:
4049	case XFS_LI_RUI:
4050	case XFS_LI_RUD:
4051	case XFS_LI_CUI:
4052	case XFS_LI_CUD:
4053	case XFS_LI_BUI:
4054	case XFS_LI_BUD:
4055		/* nothing to do in pass 1 */
4056		return 0;
4057	default:
4058		xfs_warn(log->l_mp, "%s: invalid item type (%d)",
4059			__func__, ITEM_TYPE(item));
4060		ASSERT(0);
4061		return -EIO;
4062	}
4063}
4064
4065STATIC int
4066xlog_recover_commit_pass2(
4067	struct xlog			*log,
4068	struct xlog_recover		*trans,
4069	struct list_head		*buffer_list,
4070	struct xlog_recover_item	*item)
4071{
4072	trace_xfs_log_recover_item_recover(log, trans, item, XLOG_RECOVER_PASS2);
4073
4074	switch (ITEM_TYPE(item)) {
4075	case XFS_LI_BUF:
4076		return xlog_recover_buffer_pass2(log, buffer_list, item,
4077						 trans->r_lsn);
4078	case XFS_LI_INODE:
4079		return xlog_recover_inode_pass2(log, buffer_list, item,
4080						 trans->r_lsn);
4081	case XFS_LI_EFI:
4082		return xlog_recover_efi_pass2(log, item, trans->r_lsn);
4083	case XFS_LI_EFD:
4084		return xlog_recover_efd_pass2(log, item);
4085	case XFS_LI_RUI:
4086		return xlog_recover_rui_pass2(log, item, trans->r_lsn);
4087	case XFS_LI_RUD:
4088		return xlog_recover_rud_pass2(log, item);
4089	case XFS_LI_CUI:
4090		return xlog_recover_cui_pass2(log, item, trans->r_lsn);
4091	case XFS_LI_CUD:
4092		return xlog_recover_cud_pass2(log, item);
4093	case XFS_LI_BUI:
4094		return xlog_recover_bui_pass2(log, item, trans->r_lsn);
4095	case XFS_LI_BUD:
4096		return xlog_recover_bud_pass2(log, item);
4097	case XFS_LI_DQUOT:
4098		return xlog_recover_dquot_pass2(log, buffer_list, item,
4099						trans->r_lsn);
4100	case XFS_LI_ICREATE:
4101		return xlog_recover_do_icreate_pass2(log, buffer_list, item);
4102	case XFS_LI_QUOTAOFF:
4103		/* nothing to do in pass2 */
4104		return 0;
4105	default:
4106		xfs_warn(log->l_mp, "%s: invalid item type (%d)",
4107			__func__, ITEM_TYPE(item));
4108		ASSERT(0);
4109		return -EIO;
4110	}
4111}
4112
4113STATIC int
4114xlog_recover_items_pass2(
4115	struct xlog                     *log,
4116	struct xlog_recover             *trans,
4117	struct list_head                *buffer_list,
4118	struct list_head                *item_list)
4119{
4120	struct xlog_recover_item	*item;
4121	int				error = 0;
4122
4123	list_for_each_entry(item, item_list, ri_list) {
4124		error = xlog_recover_commit_pass2(log, trans,
4125					  buffer_list, item);
4126		if (error)
4127			return error;
4128	}
4129
4130	return error;
4131}
4132
4133/*
4134 * Perform the transaction.
4135 *
4136 * If the transaction modifies a buffer or inode, do it now.  Otherwise,
4137 * EFIs and EFDs get queued up by adding entries into the AIL for them.
4138 */
4139STATIC int
4140xlog_recover_commit_trans(
4141	struct xlog		*log,
4142	struct xlog_recover	*trans,
4143	int			pass,
4144	struct list_head	*buffer_list)
4145{
4146	int				error = 0;
4147	int				items_queued = 0;
4148	struct xlog_recover_item	*item;
4149	struct xlog_recover_item	*next;
4150	LIST_HEAD			(ra_list);
4151	LIST_HEAD			(done_list);
4152
4153	#define XLOG_RECOVER_COMMIT_QUEUE_MAX 100
4154
4155	hlist_del(&trans->r_list);
4156
4157	error = xlog_recover_reorder_trans(log, trans, pass);
4158	if (error)
4159		return error;
4160
4161	list_for_each_entry_safe(item, next, &trans->r_itemq, ri_list) {
4162		switch (pass) {
4163		case XLOG_RECOVER_PASS1:
4164			error = xlog_recover_commit_pass1(log, trans, item);
4165			break;
4166		case XLOG_RECOVER_PASS2:
4167			xlog_recover_ra_pass2(log, item);
4168			list_move_tail(&item->ri_list, &ra_list);
4169			items_queued++;
4170			if (items_queued >= XLOG_RECOVER_COMMIT_QUEUE_MAX) {
4171				error = xlog_recover_items_pass2(log, trans,
4172						buffer_list, &ra_list);
4173				list_splice_tail_init(&ra_list, &done_list);
4174				items_queued = 0;
4175			}
4176
4177			break;
4178		default:
4179			ASSERT(0);
4180		}
4181
4182		if (error)
4183			goto out;
4184	}
4185
4186out:
4187	if (!list_empty(&ra_list)) {
4188		if (!error)
4189			error = xlog_recover_items_pass2(log, trans,
4190					buffer_list, &ra_list);
4191		list_splice_tail_init(&ra_list, &done_list);
4192	}
4193
4194	if (!list_empty(&done_list))
4195		list_splice_init(&done_list, &trans->r_itemq);
4196
4197	return error;
4198}
4199
4200STATIC void
4201xlog_recover_add_item(
4202	struct list_head	*head)
4203{
4204	xlog_recover_item_t	*item;
4205
4206	item = kmem_zalloc(sizeof(xlog_recover_item_t), KM_SLEEP);
4207	INIT_LIST_HEAD(&item->ri_list);
4208	list_add_tail(&item->ri_list, head);
4209}
4210
4211STATIC int
4212xlog_recover_add_to_cont_trans(
4213	struct xlog		*log,
4214	struct xlog_recover	*trans,
4215	char			*dp,
4216	int			len)
4217{
4218	xlog_recover_item_t	*item;
4219	char			*ptr, *old_ptr;
4220	int			old_len;
4221
4222	/*
4223	 * If the transaction is empty, the header was split across this and the
4224	 * previous record. Copy the rest of the header.
4225	 */
4226	if (list_empty(&trans->r_itemq)) {
4227		ASSERT(len <= sizeof(struct xfs_trans_header));
4228		if (len > sizeof(struct xfs_trans_header)) {
4229			xfs_warn(log->l_mp, "%s: bad header length", __func__);
4230			return -EIO;
4231		}
4232
4233		xlog_recover_add_item(&trans->r_itemq);
4234		ptr = (char *)&trans->r_theader +
4235				sizeof(struct xfs_trans_header) - len;
4236		memcpy(ptr, dp, len);
4237		return 0;
4238	}
4239
4240	/* take the tail entry */
4241	item = list_entry(trans->r_itemq.prev, xlog_recover_item_t, ri_list);
4242
4243	old_ptr = item->ri_buf[item->ri_cnt-1].i_addr;
4244	old_len = item->ri_buf[item->ri_cnt-1].i_len;
4245
4246	ptr = kmem_realloc(old_ptr, len + old_len, KM_SLEEP);
4247	memcpy(&ptr[old_len], dp, len);
4248	item->ri_buf[item->ri_cnt-1].i_len += len;
4249	item->ri_buf[item->ri_cnt-1].i_addr = ptr;
4250	trace_xfs_log_recover_item_add_cont(log, trans, item, 0);
4251	return 0;
4252}
4253
4254/*
4255 * The next region to add is the start of a new region.  It could be
4256 * a whole region or it could be the first part of a new region.  Because
4257 * of this, the assumption here is that the type and size fields of all
4258 * format structures fit into the first 32 bits of the structure.
4259 *
4260 * This works because all regions must be 32 bit aligned.  Therefore, we
4261 * either have both fields or we have neither field.  In the case we have
4262 * neither field, the data part of the region is zero length.  We only have
4263 * a log_op_header and can throw away the header since a new one will appear
4264 * later.  If we have at least 4 bytes, then we can determine how many regions
4265 * will appear in the current log item.
4266 */
4267STATIC int
4268xlog_recover_add_to_trans(
4269	struct xlog		*log,
4270	struct xlog_recover	*trans,
4271	char			*dp,
4272	int			len)
4273{
4274	xfs_inode_log_format_t	*in_f;			/* any will do */
4275	xlog_recover_item_t	*item;
4276	char			*ptr;
4277
4278	if (!len)
4279		return 0;
4280	if (list_empty(&trans->r_itemq)) {
4281		/* we need to catch log corruptions here */
4282		if (*(uint *)dp != XFS_TRANS_HEADER_MAGIC) {
4283			xfs_warn(log->l_mp, "%s: bad header magic number",
4284				__func__);
4285			ASSERT(0);
4286			return -EIO;
4287		}
4288
4289		if (len > sizeof(struct xfs_trans_header)) {
4290			xfs_warn(log->l_mp, "%s: bad header length", __func__);
4291			ASSERT(0);
4292			return -EIO;
4293		}
4294
4295		/*
4296		 * The transaction header can be arbitrarily split across op
4297		 * records. If we don't have the whole thing here, copy what we
4298		 * do have and handle the rest in the next record.
4299		 */
4300		if (len == sizeof(struct xfs_trans_header))
4301			xlog_recover_add_item(&trans->r_itemq);
4302		memcpy(&trans->r_theader, dp, len);
4303		return 0;
4304	}
4305
4306	ptr = kmem_alloc(len, KM_SLEEP);
4307	memcpy(ptr, dp, len);
4308	in_f = (xfs_inode_log_format_t *)ptr;
4309
4310	/* take the tail entry */
4311	item = list_entry(trans->r_itemq.prev, xlog_recover_item_t, ri_list);
4312	if (item->ri_total != 0 &&
4313	     item->ri_total == item->ri_cnt) {
4314		/* tail item is in use, get a new one */
4315		xlog_recover_add_item(&trans->r_itemq);
4316		item = list_entry(trans->r_itemq.prev,
4317					xlog_recover_item_t, ri_list);
4318	}
4319
4320	if (item->ri_total == 0) {		/* first region to be added */
4321		if (in_f->ilf_size == 0 ||
4322		    in_f->ilf_size > XLOG_MAX_REGIONS_IN_ITEM) {
4323			xfs_warn(log->l_mp,
4324		"bad number of regions (%d) in inode log format",
4325				  in_f->ilf_size);
4326			ASSERT(0);
4327			kmem_free(ptr);
4328			return -EIO;
4329		}
4330
4331		item->ri_total = in_f->ilf_size;
4332		item->ri_buf =
4333			kmem_zalloc(item->ri_total * sizeof(xfs_log_iovec_t),
4334				    KM_SLEEP);
4335	}
4336	ASSERT(item->ri_total > item->ri_cnt);
4337	/* Description region is ri_buf[0] */
4338	item->ri_buf[item->ri_cnt].i_addr = ptr;
4339	item->ri_buf[item->ri_cnt].i_len  = len;
4340	item->ri_cnt++;
4341	trace_xfs_log_recover_item_add(log, trans, item, 0);
4342	return 0;
4343}
4344
4345/*
4346 * Free up any resources allocated by the transaction
4347 *
4348 * Remember that EFIs, EFDs, and IUNLINKs are handled later.
4349 */
4350STATIC void
4351xlog_recover_free_trans(
4352	struct xlog_recover	*trans)
4353{
4354	xlog_recover_item_t	*item, *n;
4355	int			i;
4356
 
 
4357	list_for_each_entry_safe(item, n, &trans->r_itemq, ri_list) {
4358		/* Free the regions in the item. */
4359		list_del(&item->ri_list);
4360		for (i = 0; i < item->ri_cnt; i++)
4361			kmem_free(item->ri_buf[i].i_addr);
4362		/* Free the item itself */
4363		kmem_free(item->ri_buf);
4364		kmem_free(item);
4365	}
4366	/* Free the transaction recover structure */
4367	kmem_free(trans);
4368}
4369
4370/*
4371 * On error or completion, trans is freed.
4372 */
4373STATIC int
4374xlog_recovery_process_trans(
4375	struct xlog		*log,
4376	struct xlog_recover	*trans,
4377	char			*dp,
4378	unsigned int		len,
4379	unsigned int		flags,
4380	int			pass,
4381	struct list_head	*buffer_list)
4382{
4383	int			error = 0;
4384	bool			freeit = false;
4385
4386	/* mask off ophdr transaction container flags */
4387	flags &= ~XLOG_END_TRANS;
4388	if (flags & XLOG_WAS_CONT_TRANS)
4389		flags &= ~XLOG_CONTINUE_TRANS;
4390
4391	/*
4392	 * Callees must not free the trans structure. We'll decide if we need to
4393	 * free it or not based on the operation being done and it's result.
4394	 */
4395	switch (flags) {
4396	/* expected flag values */
4397	case 0:
4398	case XLOG_CONTINUE_TRANS:
4399		error = xlog_recover_add_to_trans(log, trans, dp, len);
4400		break;
4401	case XLOG_WAS_CONT_TRANS:
4402		error = xlog_recover_add_to_cont_trans(log, trans, dp, len);
4403		break;
4404	case XLOG_COMMIT_TRANS:
4405		error = xlog_recover_commit_trans(log, trans, pass,
4406						  buffer_list);
4407		/* success or fail, we are now done with this transaction. */
4408		freeit = true;
4409		break;
4410
4411	/* unexpected flag values */
4412	case XLOG_UNMOUNT_TRANS:
4413		/* just skip trans */
4414		xfs_warn(log->l_mp, "%s: Unmount LR", __func__);
4415		freeit = true;
4416		break;
4417	case XLOG_START_TRANS:
4418	default:
4419		xfs_warn(log->l_mp, "%s: bad flag 0x%x", __func__, flags);
4420		ASSERT(0);
4421		error = -EIO;
4422		break;
4423	}
4424	if (error || freeit)
4425		xlog_recover_free_trans(trans);
4426	return error;
4427}
4428
4429/*
4430 * Lookup the transaction recovery structure associated with the ID in the
4431 * current ophdr. If the transaction doesn't exist and the start flag is set in
4432 * the ophdr, then allocate a new transaction for future ID matches to find.
4433 * Either way, return what we found during the lookup - an existing transaction
4434 * or nothing.
4435 */
4436STATIC struct xlog_recover *
4437xlog_recover_ophdr_to_trans(
4438	struct hlist_head	rhash[],
4439	struct xlog_rec_header	*rhead,
4440	struct xlog_op_header	*ohead)
4441{
4442	struct xlog_recover	*trans;
4443	xlog_tid_t		tid;
4444	struct hlist_head	*rhp;
4445
4446	tid = be32_to_cpu(ohead->oh_tid);
4447	rhp = &rhash[XLOG_RHASH(tid)];
4448	hlist_for_each_entry(trans, rhp, r_list) {
4449		if (trans->r_log_tid == tid)
4450			return trans;
4451	}
4452
4453	/*
4454	 * skip over non-start transaction headers - we could be
4455	 * processing slack space before the next transaction starts
4456	 */
4457	if (!(ohead->oh_flags & XLOG_START_TRANS))
4458		return NULL;
4459
4460	ASSERT(be32_to_cpu(ohead->oh_len) == 0);
4461
4462	/*
4463	 * This is a new transaction so allocate a new recovery container to
4464	 * hold the recovery ops that will follow.
4465	 */
4466	trans = kmem_zalloc(sizeof(struct xlog_recover), KM_SLEEP);
4467	trans->r_log_tid = tid;
4468	trans->r_lsn = be64_to_cpu(rhead->h_lsn);
4469	INIT_LIST_HEAD(&trans->r_itemq);
4470	INIT_HLIST_NODE(&trans->r_list);
4471	hlist_add_head(&trans->r_list, rhp);
4472
4473	/*
4474	 * Nothing more to do for this ophdr. Items to be added to this new
4475	 * transaction will be in subsequent ophdr containers.
4476	 */
4477	return NULL;
4478}
4479
4480STATIC int
4481xlog_recover_process_ophdr(
4482	struct xlog		*log,
4483	struct hlist_head	rhash[],
4484	struct xlog_rec_header	*rhead,
4485	struct xlog_op_header	*ohead,
4486	char			*dp,
4487	char			*end,
4488	int			pass,
4489	struct list_head	*buffer_list)
4490{
4491	struct xlog_recover	*trans;
4492	unsigned int		len;
4493	int			error;
4494
4495	/* Do we understand who wrote this op? */
4496	if (ohead->oh_clientid != XFS_TRANSACTION &&
4497	    ohead->oh_clientid != XFS_LOG) {
4498		xfs_warn(log->l_mp, "%s: bad clientid 0x%x",
4499			__func__, ohead->oh_clientid);
4500		ASSERT(0);
4501		return -EIO;
4502	}
4503
4504	/*
4505	 * Check the ophdr contains all the data it is supposed to contain.
4506	 */
4507	len = be32_to_cpu(ohead->oh_len);
4508	if (dp + len > end) {
4509		xfs_warn(log->l_mp, "%s: bad length 0x%x", __func__, len);
4510		WARN_ON(1);
4511		return -EIO;
4512	}
4513
4514	trans = xlog_recover_ophdr_to_trans(rhash, rhead, ohead);
4515	if (!trans) {
4516		/* nothing to do, so skip over this ophdr */
4517		return 0;
4518	}
4519
4520	/*
4521	 * The recovered buffer queue is drained only once we know that all
4522	 * recovery items for the current LSN have been processed. This is
4523	 * required because:
4524	 *
4525	 * - Buffer write submission updates the metadata LSN of the buffer.
4526	 * - Log recovery skips items with a metadata LSN >= the current LSN of
4527	 *   the recovery item.
4528	 * - Separate recovery items against the same metadata buffer can share
4529	 *   a current LSN. I.e., consider that the LSN of a recovery item is
4530	 *   defined as the starting LSN of the first record in which its
4531	 *   transaction appears, that a record can hold multiple transactions,
4532	 *   and/or that a transaction can span multiple records.
4533	 *
4534	 * In other words, we are allowed to submit a buffer from log recovery
4535	 * once per current LSN. Otherwise, we may incorrectly skip recovery
4536	 * items and cause corruption.
4537	 *
4538	 * We don't know up front whether buffers are updated multiple times per
4539	 * LSN. Therefore, track the current LSN of each commit log record as it
4540	 * is processed and drain the queue when it changes. Use commit records
4541	 * because they are ordered correctly by the logging code.
4542	 */
4543	if (log->l_recovery_lsn != trans->r_lsn &&
4544	    ohead->oh_flags & XLOG_COMMIT_TRANS) {
4545		error = xfs_buf_delwri_submit(buffer_list);
4546		if (error)
4547			return error;
4548		log->l_recovery_lsn = trans->r_lsn;
4549	}
4550
4551	return xlog_recovery_process_trans(log, trans, dp, len,
4552					   ohead->oh_flags, pass, buffer_list);
4553}
4554
4555/*
4556 * There are two valid states of the r_state field.  0 indicates that the
4557 * transaction structure is in a normal state.  We have either seen the
4558 * start of the transaction or the last operation we added was not a partial
4559 * operation.  If the last operation we added to the transaction was a
4560 * partial operation, we need to mark r_state with XLOG_WAS_CONT_TRANS.
4561 *
4562 * NOTE: skip LRs with 0 data length.
4563 */
4564STATIC int
4565xlog_recover_process_data(
4566	struct xlog		*log,
4567	struct hlist_head	rhash[],
4568	struct xlog_rec_header	*rhead,
4569	char			*dp,
4570	int			pass,
4571	struct list_head	*buffer_list)
4572{
4573	struct xlog_op_header	*ohead;
4574	char			*end;
4575	int			num_logops;
4576	int			error;
4577
4578	end = dp + be32_to_cpu(rhead->h_len);
4579	num_logops = be32_to_cpu(rhead->h_num_logops);
4580
4581	/* check the log format matches our own - else we can't recover */
4582	if (xlog_header_check_recover(log->l_mp, rhead))
4583		return -EIO;
4584
4585	trace_xfs_log_recover_record(log, rhead, pass);
4586	while ((dp < end) && num_logops) {
4587
4588		ohead = (struct xlog_op_header *)dp;
4589		dp += sizeof(*ohead);
4590		ASSERT(dp <= end);
4591
4592		/* errors will abort recovery */
4593		error = xlog_recover_process_ophdr(log, rhash, rhead, ohead,
4594						   dp, end, pass, buffer_list);
4595		if (error)
4596			return error;
4597
4598		dp += be32_to_cpu(ohead->oh_len);
4599		num_logops--;
4600	}
4601	return 0;
4602}
4603
4604/* Recover the EFI if necessary. */
4605STATIC int
4606xlog_recover_process_efi(
4607	struct xfs_mount		*mp,
4608	struct xfs_ail			*ailp,
4609	struct xfs_log_item		*lip)
4610{
4611	struct xfs_efi_log_item		*efip;
4612	int				error;
4613
4614	/*
4615	 * Skip EFIs that we've already processed.
4616	 */
4617	efip = container_of(lip, struct xfs_efi_log_item, efi_item);
4618	if (test_bit(XFS_EFI_RECOVERED, &efip->efi_flags))
4619		return 0;
4620
4621	spin_unlock(&ailp->xa_lock);
4622	error = xfs_efi_recover(mp, efip);
4623	spin_lock(&ailp->xa_lock);
4624
4625	return error;
4626}
4627
4628/* Release the EFI since we're cancelling everything. */
4629STATIC void
4630xlog_recover_cancel_efi(
4631	struct xfs_mount		*mp,
4632	struct xfs_ail			*ailp,
4633	struct xfs_log_item		*lip)
4634{
4635	struct xfs_efi_log_item		*efip;
4636
4637	efip = container_of(lip, struct xfs_efi_log_item, efi_item);
4638
4639	spin_unlock(&ailp->xa_lock);
4640	xfs_efi_release(efip);
4641	spin_lock(&ailp->xa_lock);
4642}
4643
4644/* Recover the RUI if necessary. */
4645STATIC int
4646xlog_recover_process_rui(
4647	struct xfs_mount		*mp,
4648	struct xfs_ail			*ailp,
4649	struct xfs_log_item		*lip)
4650{
4651	struct xfs_rui_log_item		*ruip;
4652	int				error;
4653
4654	/*
4655	 * Skip RUIs that we've already processed.
4656	 */
4657	ruip = container_of(lip, struct xfs_rui_log_item, rui_item);
4658	if (test_bit(XFS_RUI_RECOVERED, &ruip->rui_flags))
4659		return 0;
4660
4661	spin_unlock(&ailp->xa_lock);
4662	error = xfs_rui_recover(mp, ruip);
4663	spin_lock(&ailp->xa_lock);
4664
4665	return error;
4666}
4667
4668/* Release the RUI since we're cancelling everything. */
4669STATIC void
4670xlog_recover_cancel_rui(
4671	struct xfs_mount		*mp,
4672	struct xfs_ail			*ailp,
4673	struct xfs_log_item		*lip)
4674{
4675	struct xfs_rui_log_item		*ruip;
4676
4677	ruip = container_of(lip, struct xfs_rui_log_item, rui_item);
4678
4679	spin_unlock(&ailp->xa_lock);
4680	xfs_rui_release(ruip);
4681	spin_lock(&ailp->xa_lock);
4682}
4683
4684/* Recover the CUI if necessary. */
4685STATIC int
4686xlog_recover_process_cui(
4687	struct xfs_mount		*mp,
4688	struct xfs_ail			*ailp,
4689	struct xfs_log_item		*lip)
 
4690{
4691	struct xfs_cui_log_item		*cuip;
4692	int				error;
4693
4694	/*
4695	 * Skip CUIs that we've already processed.
4696	 */
4697	cuip = container_of(lip, struct xfs_cui_log_item, cui_item);
4698	if (test_bit(XFS_CUI_RECOVERED, &cuip->cui_flags))
4699		return 0;
4700
4701	spin_unlock(&ailp->xa_lock);
4702	error = xfs_cui_recover(mp, cuip);
4703	spin_lock(&ailp->xa_lock);
4704
4705	return error;
4706}
4707
4708/* Release the CUI since we're cancelling everything. */
4709STATIC void
4710xlog_recover_cancel_cui(
4711	struct xfs_mount		*mp,
4712	struct xfs_ail			*ailp,
4713	struct xfs_log_item		*lip)
4714{
4715	struct xfs_cui_log_item		*cuip;
4716
4717	cuip = container_of(lip, struct xfs_cui_log_item, cui_item);
4718
4719	spin_unlock(&ailp->xa_lock);
4720	xfs_cui_release(cuip);
4721	spin_lock(&ailp->xa_lock);
4722}
4723
4724/* Recover the BUI if necessary. */
4725STATIC int
4726xlog_recover_process_bui(
4727	struct xfs_mount		*mp,
4728	struct xfs_ail			*ailp,
4729	struct xfs_log_item		*lip)
 
4730{
4731	struct xfs_bui_log_item		*buip;
4732	int				error;
4733
4734	/*
4735	 * Skip BUIs that we've already processed.
4736	 */
4737	buip = container_of(lip, struct xfs_bui_log_item, bui_item);
4738	if (test_bit(XFS_BUI_RECOVERED, &buip->bui_flags))
4739		return 0;
4740
4741	spin_unlock(&ailp->xa_lock);
4742	error = xfs_bui_recover(mp, buip);
4743	spin_lock(&ailp->xa_lock);
4744
4745	return error;
4746}
4747
4748/* Release the BUI since we're cancelling everything. */
4749STATIC void
4750xlog_recover_cancel_bui(
4751	struct xfs_mount		*mp,
4752	struct xfs_ail			*ailp,
4753	struct xfs_log_item		*lip)
4754{
4755	struct xfs_bui_log_item		*buip;
4756
4757	buip = container_of(lip, struct xfs_bui_log_item, bui_item);
4758
4759	spin_unlock(&ailp->xa_lock);
4760	xfs_bui_release(buip);
4761	spin_lock(&ailp->xa_lock);
4762}
4763
4764/* Is this log item a deferred action intent? */
4765static inline bool xlog_item_is_intent(struct xfs_log_item *lip)
4766{
4767	switch (lip->li_type) {
4768	case XFS_LI_EFI:
4769	case XFS_LI_RUI:
4770	case XFS_LI_CUI:
4771	case XFS_LI_BUI:
4772		return true;
4773	default:
4774		return false;
4775	}
4776}
4777
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4778/*
4779 * When this is called, all of the log intent items which did not have
4780 * corresponding log done items should be in the AIL.  What we do now
4781 * is update the data structures associated with each one.
4782 *
4783 * Since we process the log intent items in normal transactions, they
4784 * will be removed at some point after the commit.  This prevents us
4785 * from just walking down the list processing each one.  We'll use a
4786 * flag in the intent item to skip those that we've already processed
4787 * and use the AIL iteration mechanism's generation count to try to
4788 * speed this up at least a bit.
4789 *
4790 * When we start, we know that the intents are the only things in the
4791 * AIL.  As we process them, however, other items are added to the
4792 * AIL.
4793 */
4794STATIC int
4795xlog_recover_process_intents(
4796	struct xlog		*log)
4797{
 
 
4798	struct xfs_log_item	*lip;
 
 
4799	int			error = 0;
4800	struct xfs_ail_cursor	cur;
4801	struct xfs_ail		*ailp;
4802	xfs_lsn_t		last_lsn;
 
4803
4804	ailp = log->l_ailp;
4805	spin_lock(&ailp->xa_lock);
4806	lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
 
4807	last_lsn = xlog_assign_lsn(log->l_curr_cycle, log->l_curr_block);
 
 
4808	while (lip != NULL) {
4809		/*
4810		 * We're done when we see something other than an intent.
4811		 * There should be no intents left in the AIL now.
4812		 */
4813		if (!xlog_item_is_intent(lip)) {
4814#ifdef DEBUG
4815			for (; lip; lip = xfs_trans_ail_cursor_next(ailp, &cur))
4816				ASSERT(!xlog_item_is_intent(lip));
4817#endif
4818			break;
4819		}
4820
4821		/*
4822		 * We should never see a redo item with a LSN higher than
4823		 * the last transaction we found in the log at the start
4824		 * of recovery.
4825		 */
4826		ASSERT(XFS_LSN_CMP(last_lsn, lip->li_lsn) >= 0);
4827
 
 
 
 
 
 
4828		switch (lip->li_type) {
4829		case XFS_LI_EFI:
4830			error = xlog_recover_process_efi(log->l_mp, ailp, lip);
4831			break;
4832		case XFS_LI_RUI:
4833			error = xlog_recover_process_rui(log->l_mp, ailp, lip);
4834			break;
4835		case XFS_LI_CUI:
4836			error = xlog_recover_process_cui(log->l_mp, ailp, lip);
 
4837			break;
4838		case XFS_LI_BUI:
4839			error = xlog_recover_process_bui(log->l_mp, ailp, lip);
 
4840			break;
4841		}
4842		if (error)
4843			goto out;
4844		lip = xfs_trans_ail_cursor_next(ailp, &cur);
4845	}
4846out:
4847	xfs_trans_ail_cursor_done(&cur);
4848	spin_unlock(&ailp->xa_lock);
 
 
 
 
 
4849	return error;
4850}
4851
4852/*
4853 * A cancel occurs when the mount has failed and we're bailing out.
4854 * Release all pending log intent items so they don't pin the AIL.
4855 */
4856STATIC int
4857xlog_recover_cancel_intents(
4858	struct xlog		*log)
4859{
4860	struct xfs_log_item	*lip;
4861	int			error = 0;
4862	struct xfs_ail_cursor	cur;
4863	struct xfs_ail		*ailp;
4864
4865	ailp = log->l_ailp;
4866	spin_lock(&ailp->xa_lock);
4867	lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
4868	while (lip != NULL) {
4869		/*
4870		 * We're done when we see something other than an intent.
4871		 * There should be no intents left in the AIL now.
4872		 */
4873		if (!xlog_item_is_intent(lip)) {
4874#ifdef DEBUG
4875			for (; lip; lip = xfs_trans_ail_cursor_next(ailp, &cur))
4876				ASSERT(!xlog_item_is_intent(lip));
4877#endif
4878			break;
4879		}
4880
4881		switch (lip->li_type) {
4882		case XFS_LI_EFI:
4883			xlog_recover_cancel_efi(log->l_mp, ailp, lip);
4884			break;
4885		case XFS_LI_RUI:
4886			xlog_recover_cancel_rui(log->l_mp, ailp, lip);
4887			break;
4888		case XFS_LI_CUI:
4889			xlog_recover_cancel_cui(log->l_mp, ailp, lip);
4890			break;
4891		case XFS_LI_BUI:
4892			xlog_recover_cancel_bui(log->l_mp, ailp, lip);
4893			break;
4894		}
4895
4896		lip = xfs_trans_ail_cursor_next(ailp, &cur);
4897	}
4898
4899	xfs_trans_ail_cursor_done(&cur);
4900	spin_unlock(&ailp->xa_lock);
4901	return error;
4902}
4903
4904/*
4905 * This routine performs a transaction to null out a bad inode pointer
4906 * in an agi unlinked inode hash bucket.
4907 */
4908STATIC void
4909xlog_recover_clear_agi_bucket(
4910	xfs_mount_t	*mp,
4911	xfs_agnumber_t	agno,
4912	int		bucket)
4913{
4914	xfs_trans_t	*tp;
4915	xfs_agi_t	*agi;
4916	xfs_buf_t	*agibp;
4917	int		offset;
4918	int		error;
4919
4920	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_clearagi, 0, 0, 0, &tp);
4921	if (error)
4922		goto out_error;
4923
4924	error = xfs_read_agi(mp, tp, agno, &agibp);
4925	if (error)
4926		goto out_abort;
4927
4928	agi = XFS_BUF_TO_AGI(agibp);
4929	agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
4930	offset = offsetof(xfs_agi_t, agi_unlinked) +
4931		 (sizeof(xfs_agino_t) * bucket);
4932	xfs_trans_log_buf(tp, agibp, offset,
4933			  (offset + sizeof(xfs_agino_t) - 1));
4934
4935	error = xfs_trans_commit(tp);
4936	if (error)
4937		goto out_error;
4938	return;
4939
4940out_abort:
4941	xfs_trans_cancel(tp);
4942out_error:
4943	xfs_warn(mp, "%s: failed to clear agi %d. Continuing.", __func__, agno);
4944	return;
4945}
4946
4947STATIC xfs_agino_t
4948xlog_recover_process_one_iunlink(
4949	struct xfs_mount		*mp,
4950	xfs_agnumber_t			agno,
4951	xfs_agino_t			agino,
4952	int				bucket)
4953{
4954	struct xfs_buf			*ibp;
4955	struct xfs_dinode		*dip;
4956	struct xfs_inode		*ip;
4957	xfs_ino_t			ino;
4958	int				error;
4959
4960	ino = XFS_AGINO_TO_INO(mp, agno, agino);
4961	error = xfs_iget(mp, NULL, ino, 0, 0, &ip);
4962	if (error)
4963		goto fail;
4964
4965	/*
4966	 * Get the on disk inode to find the next inode in the bucket.
4967	 */
4968	error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &ibp, 0, 0);
4969	if (error)
4970		goto fail_iput;
4971
4972	xfs_iflags_clear(ip, XFS_IRECOVERY);
4973	ASSERT(VFS_I(ip)->i_nlink == 0);
4974	ASSERT(VFS_I(ip)->i_mode != 0);
4975
4976	/* setup for the next pass */
4977	agino = be32_to_cpu(dip->di_next_unlinked);
4978	xfs_buf_relse(ibp);
4979
4980	/*
4981	 * Prevent any DMAPI event from being sent when the reference on
4982	 * the inode is dropped.
4983	 */
4984	ip->i_d.di_dmevmask = 0;
4985
4986	IRELE(ip);
4987	return agino;
4988
4989 fail_iput:
4990	IRELE(ip);
4991 fail:
4992	/*
4993	 * We can't read in the inode this bucket points to, or this inode
4994	 * is messed up.  Just ditch this bucket of inodes.  We will lose
4995	 * some inodes and space, but at least we won't hang.
4996	 *
4997	 * Call xlog_recover_clear_agi_bucket() to perform a transaction to
4998	 * clear the inode pointer in the bucket.
4999	 */
5000	xlog_recover_clear_agi_bucket(mp, agno, bucket);
5001	return NULLAGINO;
5002}
5003
5004/*
5005 * xlog_iunlink_recover
5006 *
5007 * This is called during recovery to process any inodes which
5008 * we unlinked but not freed when the system crashed.  These
5009 * inodes will be on the lists in the AGI blocks.  What we do
5010 * here is scan all the AGIs and fully truncate and free any
5011 * inodes found on the lists.  Each inode is removed from the
5012 * lists when it has been fully truncated and is freed.  The
5013 * freeing of the inode and its removal from the list must be
5014 * atomic.
5015 */
5016STATIC void
5017xlog_recover_process_iunlinks(
5018	struct xlog	*log)
5019{
5020	xfs_mount_t	*mp;
5021	xfs_agnumber_t	agno;
5022	xfs_agi_t	*agi;
5023	xfs_buf_t	*agibp;
5024	xfs_agino_t	agino;
5025	int		bucket;
5026	int		error;
5027	uint		mp_dmevmask;
5028
5029	mp = log->l_mp;
5030
5031	/*
5032	 * Prevent any DMAPI event from being sent while in this function.
5033	 */
5034	mp_dmevmask = mp->m_dmevmask;
5035	mp->m_dmevmask = 0;
5036
5037	for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
5038		/*
5039		 * Find the agi for this ag.
5040		 */
5041		error = xfs_read_agi(mp, NULL, agno, &agibp);
5042		if (error) {
5043			/*
5044			 * AGI is b0rked. Don't process it.
5045			 *
5046			 * We should probably mark the filesystem as corrupt
5047			 * after we've recovered all the ag's we can....
5048			 */
5049			continue;
5050		}
5051		/*
5052		 * Unlock the buffer so that it can be acquired in the normal
5053		 * course of the transaction to truncate and free each inode.
5054		 * Because we are not racing with anyone else here for the AGI
5055		 * buffer, we don't even need to hold it locked to read the
5056		 * initial unlinked bucket entries out of the buffer. We keep
5057		 * buffer reference though, so that it stays pinned in memory
5058		 * while we need the buffer.
5059		 */
5060		agi = XFS_BUF_TO_AGI(agibp);
5061		xfs_buf_unlock(agibp);
5062
5063		for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++) {
5064			agino = be32_to_cpu(agi->agi_unlinked[bucket]);
5065			while (agino != NULLAGINO) {
5066				agino = xlog_recover_process_one_iunlink(mp,
5067							agno, agino, bucket);
5068			}
5069		}
5070		xfs_buf_rele(agibp);
5071	}
5072
5073	mp->m_dmevmask = mp_dmevmask;
5074}
5075
5076STATIC int
5077xlog_unpack_data(
5078	struct xlog_rec_header	*rhead,
5079	char			*dp,
5080	struct xlog		*log)
5081{
5082	int			i, j, k;
5083
5084	for (i = 0; i < BTOBB(be32_to_cpu(rhead->h_len)) &&
5085		  i < (XLOG_HEADER_CYCLE_SIZE / BBSIZE); i++) {
5086		*(__be32 *)dp = *(__be32 *)&rhead->h_cycle_data[i];
5087		dp += BBSIZE;
5088	}
5089
5090	if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
5091		xlog_in_core_2_t *xhdr = (xlog_in_core_2_t *)rhead;
5092		for ( ; i < BTOBB(be32_to_cpu(rhead->h_len)); i++) {
5093			j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
5094			k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
5095			*(__be32 *)dp = xhdr[j].hic_xheader.xh_cycle_data[k];
5096			dp += BBSIZE;
5097		}
5098	}
5099
5100	return 0;
5101}
5102
5103/*
5104 * CRC check, unpack and process a log record.
5105 */
5106STATIC int
5107xlog_recover_process(
5108	struct xlog		*log,
5109	struct hlist_head	rhash[],
5110	struct xlog_rec_header	*rhead,
5111	char			*dp,
5112	int			pass,
5113	struct list_head	*buffer_list)
5114{
5115	int			error;
5116	__le32			old_crc = rhead->h_crc;
5117	__le32			crc;
5118
5119
5120	crc = xlog_cksum(log, rhead, dp, be32_to_cpu(rhead->h_len));
5121
5122	/*
5123	 * Nothing else to do if this is a CRC verification pass. Just return
5124	 * if this a record with a non-zero crc. Unfortunately, mkfs always
5125	 * sets old_crc to 0 so we must consider this valid even on v5 supers.
5126	 * Otherwise, return EFSBADCRC on failure so the callers up the stack
5127	 * know precisely what failed.
5128	 */
5129	if (pass == XLOG_RECOVER_CRCPASS) {
5130		if (old_crc && crc != old_crc)
5131			return -EFSBADCRC;
5132		return 0;
5133	}
5134
5135	/*
5136	 * We're in the normal recovery path. Issue a warning if and only if the
5137	 * CRC in the header is non-zero. This is an advisory warning and the
5138	 * zero CRC check prevents warnings from being emitted when upgrading
5139	 * the kernel from one that does not add CRCs by default.
5140	 */
5141	if (crc != old_crc) {
5142		if (old_crc || xfs_sb_version_hascrc(&log->l_mp->m_sb)) {
5143			xfs_alert(log->l_mp,
5144		"log record CRC mismatch: found 0x%x, expected 0x%x.",
5145					le32_to_cpu(old_crc),
5146					le32_to_cpu(crc));
5147			xfs_hex_dump(dp, 32);
5148		}
5149
5150		/*
5151		 * If the filesystem is CRC enabled, this mismatch becomes a
5152		 * fatal log corruption failure.
5153		 */
5154		if (xfs_sb_version_hascrc(&log->l_mp->m_sb))
5155			return -EFSCORRUPTED;
5156	}
5157
5158	error = xlog_unpack_data(rhead, dp, log);
5159	if (error)
5160		return error;
5161
5162	return xlog_recover_process_data(log, rhash, rhead, dp, pass,
5163					 buffer_list);
5164}
5165
5166STATIC int
5167xlog_valid_rec_header(
5168	struct xlog		*log,
5169	struct xlog_rec_header	*rhead,
5170	xfs_daddr_t		blkno)
5171{
5172	int			hlen;
5173
5174	if (unlikely(rhead->h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM))) {
5175		XFS_ERROR_REPORT("xlog_valid_rec_header(1)",
5176				XFS_ERRLEVEL_LOW, log->l_mp);
5177		return -EFSCORRUPTED;
5178	}
5179	if (unlikely(
5180	    (!rhead->h_version ||
5181	    (be32_to_cpu(rhead->h_version) & (~XLOG_VERSION_OKBITS))))) {
5182		xfs_warn(log->l_mp, "%s: unrecognised log version (%d).",
5183			__func__, be32_to_cpu(rhead->h_version));
5184		return -EIO;
5185	}
5186
5187	/* LR body must have data or it wouldn't have been written */
5188	hlen = be32_to_cpu(rhead->h_len);
5189	if (unlikely( hlen <= 0 || hlen > INT_MAX )) {
5190		XFS_ERROR_REPORT("xlog_valid_rec_header(2)",
5191				XFS_ERRLEVEL_LOW, log->l_mp);
5192		return -EFSCORRUPTED;
5193	}
5194	if (unlikely( blkno > log->l_logBBsize || blkno > INT_MAX )) {
5195		XFS_ERROR_REPORT("xlog_valid_rec_header(3)",
5196				XFS_ERRLEVEL_LOW, log->l_mp);
5197		return -EFSCORRUPTED;
5198	}
5199	return 0;
5200}
5201
5202/*
5203 * Read the log from tail to head and process the log records found.
5204 * Handle the two cases where the tail and head are in the same cycle
5205 * and where the active portion of the log wraps around the end of
5206 * the physical log separately.  The pass parameter is passed through
5207 * to the routines called to process the data and is not looked at
5208 * here.
5209 */
5210STATIC int
5211xlog_do_recovery_pass(
5212	struct xlog		*log,
5213	xfs_daddr_t		head_blk,
5214	xfs_daddr_t		tail_blk,
5215	int			pass,
5216	xfs_daddr_t		*first_bad)	/* out: first bad log rec */
5217{
5218	xlog_rec_header_t	*rhead;
5219	xfs_daddr_t		blk_no;
5220	xfs_daddr_t		rhead_blk;
5221	char			*offset;
5222	xfs_buf_t		*hbp, *dbp;
5223	int			error = 0, h_size, h_len;
5224	int			error2 = 0;
5225	int			bblks, split_bblks;
5226	int			hblks, split_hblks, wrapped_hblks;
 
5227	struct hlist_head	rhash[XLOG_RHASH_SIZE];
5228	LIST_HEAD		(buffer_list);
5229
5230	ASSERT(head_blk != tail_blk);
5231	rhead_blk = 0;
 
 
 
5232
5233	/*
5234	 * Read the header of the tail block and get the iclog buffer size from
5235	 * h_size.  Use this to tell how many sectors make up the log header.
5236	 */
5237	if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
5238		/*
5239		 * When using variable length iclogs, read first sector of
5240		 * iclog header and extract the header size from it.  Get a
5241		 * new hbp that is the correct size.
5242		 */
5243		hbp = xlog_get_bp(log, 1);
5244		if (!hbp)
5245			return -ENOMEM;
5246
5247		error = xlog_bread(log, tail_blk, 1, hbp, &offset);
5248		if (error)
5249			goto bread_err1;
5250
5251		rhead = (xlog_rec_header_t *)offset;
5252		error = xlog_valid_rec_header(log, rhead, tail_blk);
5253		if (error)
5254			goto bread_err1;
5255
5256		/*
5257		 * xfsprogs has a bug where record length is based on lsunit but
5258		 * h_size (iclog size) is hardcoded to 32k. Now that we
5259		 * unconditionally CRC verify the unmount record, this means the
5260		 * log buffer can be too small for the record and cause an
5261		 * overrun.
5262		 *
5263		 * Detect this condition here. Use lsunit for the buffer size as
5264		 * long as this looks like the mkfs case. Otherwise, return an
5265		 * error to avoid a buffer overrun.
5266		 */
5267		h_size = be32_to_cpu(rhead->h_size);
5268		h_len = be32_to_cpu(rhead->h_len);
5269		if (h_len > h_size) {
5270			if (h_len <= log->l_mp->m_logbsize &&
5271			    be32_to_cpu(rhead->h_num_logops) == 1) {
5272				xfs_warn(log->l_mp,
5273		"invalid iclog size (%d bytes), using lsunit (%d bytes)",
5274					 h_size, log->l_mp->m_logbsize);
5275				h_size = log->l_mp->m_logbsize;
5276			} else
5277				return -EFSCORRUPTED;
5278		}
5279
5280		if ((be32_to_cpu(rhead->h_version) & XLOG_VERSION_2) &&
5281		    (h_size > XLOG_HEADER_CYCLE_SIZE)) {
5282			hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
5283			if (h_size % XLOG_HEADER_CYCLE_SIZE)
5284				hblks++;
5285			xlog_put_bp(hbp);
5286			hbp = xlog_get_bp(log, hblks);
5287		} else {
5288			hblks = 1;
5289		}
5290	} else {
5291		ASSERT(log->l_sectBBsize == 1);
5292		hblks = 1;
5293		hbp = xlog_get_bp(log, 1);
5294		h_size = XLOG_BIG_RECORD_BSIZE;
5295	}
5296
5297	if (!hbp)
5298		return -ENOMEM;
5299	dbp = xlog_get_bp(log, BTOBB(h_size));
5300	if (!dbp) {
5301		xlog_put_bp(hbp);
5302		return -ENOMEM;
5303	}
5304
5305	memset(rhash, 0, sizeof(rhash));
5306	blk_no = rhead_blk = tail_blk;
5307	if (tail_blk > head_blk) {
5308		/*
5309		 * Perform recovery around the end of the physical log.
5310		 * When the head is not on the same cycle number as the tail,
5311		 * we can't do a sequential recovery.
5312		 */
5313		while (blk_no < log->l_logBBsize) {
5314			/*
5315			 * Check for header wrapping around physical end-of-log
5316			 */
5317			offset = hbp->b_addr;
5318			split_hblks = 0;
5319			wrapped_hblks = 0;
5320			if (blk_no + hblks <= log->l_logBBsize) {
5321				/* Read header in one read */
5322				error = xlog_bread(log, blk_no, hblks, hbp,
5323						   &offset);
5324				if (error)
5325					goto bread_err2;
5326			} else {
5327				/* This LR is split across physical log end */
5328				if (blk_no != log->l_logBBsize) {
5329					/* some data before physical log end */
5330					ASSERT(blk_no <= INT_MAX);
5331					split_hblks = log->l_logBBsize - (int)blk_no;
5332					ASSERT(split_hblks > 0);
5333					error = xlog_bread(log, blk_no,
5334							   split_hblks, hbp,
5335							   &offset);
5336					if (error)
5337						goto bread_err2;
5338				}
5339
5340				/*
5341				 * Note: this black magic still works with
5342				 * large sector sizes (non-512) only because:
5343				 * - we increased the buffer size originally
5344				 *   by 1 sector giving us enough extra space
5345				 *   for the second read;
5346				 * - the log start is guaranteed to be sector
5347				 *   aligned;
5348				 * - we read the log end (LR header start)
5349				 *   _first_, then the log start (LR header end)
5350				 *   - order is important.
5351				 */
5352				wrapped_hblks = hblks - split_hblks;
5353				error = xlog_bread_offset(log, 0,
5354						wrapped_hblks, hbp,
5355						offset + BBTOB(split_hblks));
5356				if (error)
5357					goto bread_err2;
5358			}
5359			rhead = (xlog_rec_header_t *)offset;
5360			error = xlog_valid_rec_header(log, rhead,
5361						split_hblks ? blk_no : 0);
5362			if (error)
5363				goto bread_err2;
5364
5365			bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
5366			blk_no += hblks;
5367
5368			/* Read in data for log record */
5369			if (blk_no + bblks <= log->l_logBBsize) {
5370				error = xlog_bread(log, blk_no, bblks, dbp,
 
 
 
 
 
 
 
 
 
 
5371						   &offset);
5372				if (error)
5373					goto bread_err2;
5374			} else {
5375				/* This log record is split across the
5376				 * physical end of log */
5377				offset = dbp->b_addr;
5378				split_bblks = 0;
5379				if (blk_no != log->l_logBBsize) {
5380					/* some data is before the physical
5381					 * end of log */
5382					ASSERT(!wrapped_hblks);
5383					ASSERT(blk_no <= INT_MAX);
5384					split_bblks =
5385						log->l_logBBsize - (int)blk_no;
5386					ASSERT(split_bblks > 0);
5387					error = xlog_bread(log, blk_no,
5388							split_bblks, dbp,
5389							&offset);
5390					if (error)
5391						goto bread_err2;
5392				}
5393
5394				/*
5395				 * Note: this black magic still works with
5396				 * large sector sizes (non-512) only because:
5397				 * - we increased the buffer size originally
5398				 *   by 1 sector giving us enough extra space
5399				 *   for the second read;
5400				 * - the log start is guaranteed to be sector
5401				 *   aligned;
5402				 * - we read the log end (LR header start)
5403				 *   _first_, then the log start (LR header end)
5404				 *   - order is important.
5405				 */
5406				error = xlog_bread_offset(log, 0,
5407						bblks - split_bblks, dbp,
5408						offset + BBTOB(split_bblks));
5409				if (error)
5410					goto bread_err2;
5411			}
5412
5413			error = xlog_recover_process(log, rhash, rhead, offset,
5414						     pass, &buffer_list);
5415			if (error)
5416				goto bread_err2;
5417
5418			blk_no += bblks;
5419			rhead_blk = blk_no;
5420		}
5421
5422		ASSERT(blk_no >= log->l_logBBsize);
5423		blk_no -= log->l_logBBsize;
5424		rhead_blk = blk_no;
5425	}
5426
5427	/* read first part of physical log */
5428	while (blk_no < head_blk) {
5429		error = xlog_bread(log, blk_no, hblks, hbp, &offset);
5430		if (error)
5431			goto bread_err2;
5432
5433		rhead = (xlog_rec_header_t *)offset;
5434		error = xlog_valid_rec_header(log, rhead, blk_no);
5435		if (error)
5436			goto bread_err2;
5437
5438		/* blocks in data section */
5439		bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
5440		error = xlog_bread(log, blk_no+hblks, bblks, dbp,
5441				   &offset);
5442		if (error)
5443			goto bread_err2;
5444
5445		error = xlog_recover_process(log, rhash, rhead, offset, pass,
5446					     &buffer_list);
5447		if (error)
5448			goto bread_err2;
5449
5450		blk_no += bblks + hblks;
5451		rhead_blk = blk_no;
5452	}
5453
5454 bread_err2:
5455	xlog_put_bp(dbp);
5456 bread_err1:
5457	xlog_put_bp(hbp);
5458
5459	/*
5460	 * Submit buffers that have been added from the last record processed,
5461	 * regardless of error status.
5462	 */
5463	if (!list_empty(&buffer_list))
5464		error2 = xfs_buf_delwri_submit(&buffer_list);
5465
5466	if (error && first_bad)
5467		*first_bad = rhead_blk;
5468
 
 
 
 
 
 
 
 
 
 
 
 
 
5469	return error ? error : error2;
5470}
5471
5472/*
5473 * Do the recovery of the log.  We actually do this in two phases.
5474 * The two passes are necessary in order to implement the function
5475 * of cancelling a record written into the log.  The first pass
5476 * determines those things which have been cancelled, and the
5477 * second pass replays log items normally except for those which
5478 * have been cancelled.  The handling of the replay and cancellations
5479 * takes place in the log item type specific routines.
5480 *
5481 * The table of items which have cancel records in the log is allocated
5482 * and freed at this level, since only here do we know when all of
5483 * the log recovery has been completed.
5484 */
5485STATIC int
5486xlog_do_log_recovery(
5487	struct xlog	*log,
5488	xfs_daddr_t	head_blk,
5489	xfs_daddr_t	tail_blk)
5490{
5491	int		error, i;
5492
5493	ASSERT(head_blk != tail_blk);
5494
5495	/*
5496	 * First do a pass to find all of the cancelled buf log items.
5497	 * Store them in the buf_cancel_table for use in the second pass.
5498	 */
5499	log->l_buf_cancel_table = kmem_zalloc(XLOG_BC_TABLE_SIZE *
5500						 sizeof(struct list_head),
5501						 KM_SLEEP);
5502	for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
5503		INIT_LIST_HEAD(&log->l_buf_cancel_table[i]);
5504
5505	error = xlog_do_recovery_pass(log, head_blk, tail_blk,
5506				      XLOG_RECOVER_PASS1, NULL);
5507	if (error != 0) {
5508		kmem_free(log->l_buf_cancel_table);
5509		log->l_buf_cancel_table = NULL;
5510		return error;
5511	}
5512	/*
5513	 * Then do a second pass to actually recover the items in the log.
5514	 * When it is complete free the table of buf cancel items.
5515	 */
5516	error = xlog_do_recovery_pass(log, head_blk, tail_blk,
5517				      XLOG_RECOVER_PASS2, NULL);
5518#ifdef DEBUG
5519	if (!error) {
5520		int	i;
5521
5522		for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
5523			ASSERT(list_empty(&log->l_buf_cancel_table[i]));
5524	}
5525#endif	/* DEBUG */
5526
5527	kmem_free(log->l_buf_cancel_table);
5528	log->l_buf_cancel_table = NULL;
5529
5530	return error;
5531}
5532
5533/*
5534 * Do the actual recovery
5535 */
5536STATIC int
5537xlog_do_recover(
5538	struct xlog	*log,
5539	xfs_daddr_t	head_blk,
5540	xfs_daddr_t	tail_blk)
5541{
5542	struct xfs_mount *mp = log->l_mp;
5543	int		error;
5544	xfs_buf_t	*bp;
5545	xfs_sb_t	*sbp;
5546
 
 
5547	/*
5548	 * First replay the images in the log.
5549	 */
5550	error = xlog_do_log_recovery(log, head_blk, tail_blk);
5551	if (error)
5552		return error;
5553
5554	/*
5555	 * If IO errors happened during recovery, bail out.
5556	 */
5557	if (XFS_FORCED_SHUTDOWN(mp)) {
5558		return -EIO;
5559	}
5560
5561	/*
5562	 * We now update the tail_lsn since much of the recovery has completed
5563	 * and there may be space available to use.  If there were no extent
5564	 * or iunlinks, we can free up the entire log and set the tail_lsn to
5565	 * be the last_sync_lsn.  This was set in xlog_find_tail to be the
5566	 * lsn of the last known good LR on disk.  If there are extent frees
5567	 * or iunlinks they will have some entries in the AIL; so we look at
5568	 * the AIL to determine how to set the tail_lsn.
5569	 */
5570	xlog_assign_tail_lsn(mp);
5571
5572	/*
5573	 * Now that we've finished replaying all buffer and inode
5574	 * updates, re-read in the superblock and reverify it.
5575	 */
5576	bp = xfs_getsb(mp, 0);
5577	bp->b_flags &= ~(XBF_DONE | XBF_ASYNC);
5578	ASSERT(!(bp->b_flags & XBF_WRITE));
5579	bp->b_flags |= XBF_READ;
5580	bp->b_ops = &xfs_sb_buf_ops;
5581
5582	error = xfs_buf_submit_wait(bp);
5583	if (error) {
5584		if (!XFS_FORCED_SHUTDOWN(mp)) {
5585			xfs_buf_ioerror_alert(bp, __func__);
5586			ASSERT(0);
5587		}
5588		xfs_buf_relse(bp);
5589		return error;
5590	}
5591
5592	/* Convert superblock from on-disk format */
5593	sbp = &mp->m_sb;
5594	xfs_sb_from_disk(sbp, XFS_BUF_TO_SBP(bp));
5595	xfs_buf_relse(bp);
5596
5597	/* re-initialise in-core superblock and geometry structures */
5598	xfs_reinit_percpu_counters(mp);
5599	error = xfs_initialize_perag(mp, sbp->sb_agcount, &mp->m_maxagi);
5600	if (error) {
5601		xfs_warn(mp, "Failed post-recovery per-ag init: %d", error);
5602		return error;
5603	}
5604	mp->m_alloc_set_aside = xfs_alloc_set_aside(mp);
5605
5606	xlog_recover_check_summary(log);
5607
5608	/* Normal transactions can now occur */
5609	log->l_flags &= ~XLOG_ACTIVE_RECOVERY;
5610	return 0;
5611}
5612
5613/*
5614 * Perform recovery and re-initialize some log variables in xlog_find_tail.
5615 *
5616 * Return error or zero.
5617 */
5618int
5619xlog_recover(
5620	struct xlog	*log)
5621{
5622	xfs_daddr_t	head_blk, tail_blk;
5623	int		error;
5624
5625	/* find the tail of the log */
5626	error = xlog_find_tail(log, &head_blk, &tail_blk);
5627	if (error)
5628		return error;
5629
5630	/*
5631	 * The superblock was read before the log was available and thus the LSN
5632	 * could not be verified. Check the superblock LSN against the current
5633	 * LSN now that it's known.
5634	 */
5635	if (xfs_sb_version_hascrc(&log->l_mp->m_sb) &&
5636	    !xfs_log_check_lsn(log->l_mp, log->l_mp->m_sb.sb_lsn))
5637		return -EINVAL;
5638
5639	if (tail_blk != head_blk) {
5640		/* There used to be a comment here:
5641		 *
5642		 * disallow recovery on read-only mounts.  note -- mount
5643		 * checks for ENOSPC and turns it into an intelligent
5644		 * error message.
5645		 * ...but this is no longer true.  Now, unless you specify
5646		 * NORECOVERY (in which case this function would never be
5647		 * called), we just go ahead and recover.  We do this all
5648		 * under the vfs layer, so we can get away with it unless
5649		 * the device itself is read-only, in which case we fail.
5650		 */
5651		if ((error = xfs_dev_is_read_only(log->l_mp, "recovery"))) {
5652			return error;
5653		}
5654
5655		/*
5656		 * Version 5 superblock log feature mask validation. We know the
5657		 * log is dirty so check if there are any unknown log features
5658		 * in what we need to recover. If there are unknown features
5659		 * (e.g. unsupported transactions, then simply reject the
5660		 * attempt at recovery before touching anything.
5661		 */
5662		if (XFS_SB_VERSION_NUM(&log->l_mp->m_sb) == XFS_SB_VERSION_5 &&
5663		    xfs_sb_has_incompat_log_feature(&log->l_mp->m_sb,
5664					XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN)) {
5665			xfs_warn(log->l_mp,
5666"Superblock has unknown incompatible log features (0x%x) enabled.",
5667				(log->l_mp->m_sb.sb_features_log_incompat &
5668					XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN));
5669			xfs_warn(log->l_mp,
5670"The log can not be fully and/or safely recovered by this kernel.");
5671			xfs_warn(log->l_mp,
5672"Please recover the log on a kernel that supports the unknown features.");
5673			return -EINVAL;
5674		}
5675
5676		/*
5677		 * Delay log recovery if the debug hook is set. This is debug
5678		 * instrumention to coordinate simulation of I/O failures with
5679		 * log recovery.
5680		 */
5681		if (xfs_globals.log_recovery_delay) {
5682			xfs_notice(log->l_mp,
5683				"Delaying log recovery for %d seconds.",
5684				xfs_globals.log_recovery_delay);
5685			msleep(xfs_globals.log_recovery_delay * 1000);
5686		}
5687
5688		xfs_notice(log->l_mp, "Starting recovery (logdev: %s)",
5689				log->l_mp->m_logname ? log->l_mp->m_logname
5690						     : "internal");
5691
5692		error = xlog_do_recover(log, head_blk, tail_blk);
5693		log->l_flags |= XLOG_RECOVERY_NEEDED;
5694	}
5695	return error;
5696}
5697
5698/*
5699 * In the first part of recovery we replay inodes and buffers and build
5700 * up the list of extent free items which need to be processed.  Here
5701 * we process the extent free items and clean up the on disk unlinked
5702 * inode lists.  This is separated from the first part of recovery so
5703 * that the root and real-time bitmap inodes can be read in from disk in
5704 * between the two stages.  This is necessary so that we can free space
5705 * in the real-time portion of the file system.
5706 */
5707int
5708xlog_recover_finish(
5709	struct xlog	*log)
5710{
5711	/*
5712	 * Now we're ready to do the transactions needed for the
5713	 * rest of recovery.  Start with completing all the extent
5714	 * free intent records and then process the unlinked inode
5715	 * lists.  At this point, we essentially run in normal mode
5716	 * except that we're still performing recovery actions
5717	 * rather than accepting new requests.
5718	 */
5719	if (log->l_flags & XLOG_RECOVERY_NEEDED) {
5720		int	error;
5721		error = xlog_recover_process_intents(log);
5722		if (error) {
5723			xfs_alert(log->l_mp, "Failed to recover intents");
5724			return error;
5725		}
5726
5727		/*
5728		 * Sync the log to get all the intents out of the AIL.
5729		 * This isn't absolutely necessary, but it helps in
5730		 * case the unlink transactions would have problems
5731		 * pushing the intents out of the way.
5732		 */
5733		xfs_log_force(log->l_mp, XFS_LOG_SYNC);
5734
5735		xlog_recover_process_iunlinks(log);
5736
5737		xlog_recover_check_summary(log);
5738
5739		xfs_notice(log->l_mp, "Ending recovery (logdev: %s)",
5740				log->l_mp->m_logname ? log->l_mp->m_logname
5741						     : "internal");
5742		log->l_flags &= ~XLOG_RECOVERY_NEEDED;
5743	} else {
5744		xfs_info(log->l_mp, "Ending clean mount");
5745	}
5746	return 0;
5747}
5748
5749int
5750xlog_recover_cancel(
5751	struct xlog	*log)
5752{
5753	int		error = 0;
5754
5755	if (log->l_flags & XLOG_RECOVERY_NEEDED)
5756		error = xlog_recover_cancel_intents(log);
5757
5758	return error;
5759}
5760
5761#if defined(DEBUG)
5762/*
5763 * Read all of the agf and agi counters and check that they
5764 * are consistent with the superblock counters.
5765 */
5766void
5767xlog_recover_check_summary(
5768	struct xlog	*log)
5769{
5770	xfs_mount_t	*mp;
5771	xfs_agf_t	*agfp;
5772	xfs_buf_t	*agfbp;
5773	xfs_buf_t	*agibp;
5774	xfs_agnumber_t	agno;
5775	__uint64_t	freeblks;
5776	__uint64_t	itotal;
5777	__uint64_t	ifree;
5778	int		error;
5779
5780	mp = log->l_mp;
5781
5782	freeblks = 0LL;
5783	itotal = 0LL;
5784	ifree = 0LL;
5785	for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
5786		error = xfs_read_agf(mp, NULL, agno, 0, &agfbp);
5787		if (error) {
5788			xfs_alert(mp, "%s agf read failed agno %d error %d",
5789						__func__, agno, error);
5790		} else {
5791			agfp = XFS_BUF_TO_AGF(agfbp);
5792			freeblks += be32_to_cpu(agfp->agf_freeblks) +
5793				    be32_to_cpu(agfp->agf_flcount);
5794			xfs_buf_relse(agfbp);
5795		}
5796
5797		error = xfs_read_agi(mp, NULL, agno, &agibp);
5798		if (error) {
5799			xfs_alert(mp, "%s agi read failed agno %d error %d",
5800						__func__, agno, error);
5801		} else {
5802			struct xfs_agi	*agi = XFS_BUF_TO_AGI(agibp);
5803
5804			itotal += be32_to_cpu(agi->agi_count);
5805			ifree += be32_to_cpu(agi->agi_freecount);
5806			xfs_buf_relse(agibp);
5807		}
5808	}
5809}
5810#endif /* DEBUG */