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v6.2
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
   4 * All Rights Reserved.
   5 */
   6#include "xfs.h"
   7#include "xfs_fs.h"
   8#include "xfs_shared.h"
   9#include "xfs_format.h"
  10#include "xfs_log_format.h"
  11#include "xfs_trans_resv.h"
  12#include "xfs_bit.h"
  13#include "xfs_mount.h"
  14#include "xfs_inode.h"
  15#include "xfs_btree.h"
  16#include "xfs_ialloc.h"
  17#include "xfs_ialloc_btree.h"
  18#include "xfs_alloc.h"
  19#include "xfs_errortag.h"
  20#include "xfs_error.h"
  21#include "xfs_bmap.h"
  22#include "xfs_trans.h"
  23#include "xfs_buf_item.h"
  24#include "xfs_icreate_item.h"
  25#include "xfs_icache.h"
  26#include "xfs_trace.h"
  27#include "xfs_log.h"
  28#include "xfs_rmap.h"
  29#include "xfs_ag.h"
 
  30
  31/*
  32 * Lookup a record by ino in the btree given by cur.
  33 */
  34int					/* error */
  35xfs_inobt_lookup(
  36	struct xfs_btree_cur	*cur,	/* btree cursor */
  37	xfs_agino_t		ino,	/* starting inode of chunk */
  38	xfs_lookup_t		dir,	/* <=, >=, == */
  39	int			*stat)	/* success/failure */
  40{
  41	cur->bc_rec.i.ir_startino = ino;
  42	cur->bc_rec.i.ir_holemask = 0;
  43	cur->bc_rec.i.ir_count = 0;
  44	cur->bc_rec.i.ir_freecount = 0;
  45	cur->bc_rec.i.ir_free = 0;
  46	return xfs_btree_lookup(cur, dir, stat);
  47}
  48
  49/*
  50 * Update the record referred to by cur to the value given.
  51 * This either works (return 0) or gets an EFSCORRUPTED error.
  52 */
  53STATIC int				/* error */
  54xfs_inobt_update(
  55	struct xfs_btree_cur	*cur,	/* btree cursor */
  56	xfs_inobt_rec_incore_t	*irec)	/* btree record */
  57{
  58	union xfs_btree_rec	rec;
  59
  60	rec.inobt.ir_startino = cpu_to_be32(irec->ir_startino);
  61	if (xfs_has_sparseinodes(cur->bc_mp)) {
  62		rec.inobt.ir_u.sp.ir_holemask = cpu_to_be16(irec->ir_holemask);
  63		rec.inobt.ir_u.sp.ir_count = irec->ir_count;
  64		rec.inobt.ir_u.sp.ir_freecount = irec->ir_freecount;
  65	} else {
  66		/* ir_holemask/ir_count not supported on-disk */
  67		rec.inobt.ir_u.f.ir_freecount = cpu_to_be32(irec->ir_freecount);
  68	}
  69	rec.inobt.ir_free = cpu_to_be64(irec->ir_free);
  70	return xfs_btree_update(cur, &rec);
  71}
  72
  73/* Convert on-disk btree record to incore inobt record. */
  74void
  75xfs_inobt_btrec_to_irec(
  76	struct xfs_mount		*mp,
  77	const union xfs_btree_rec	*rec,
  78	struct xfs_inobt_rec_incore	*irec)
  79{
  80	irec->ir_startino = be32_to_cpu(rec->inobt.ir_startino);
  81	if (xfs_has_sparseinodes(mp)) {
  82		irec->ir_holemask = be16_to_cpu(rec->inobt.ir_u.sp.ir_holemask);
  83		irec->ir_count = rec->inobt.ir_u.sp.ir_count;
  84		irec->ir_freecount = rec->inobt.ir_u.sp.ir_freecount;
  85	} else {
  86		/*
  87		 * ir_holemask/ir_count not supported on-disk. Fill in hardcoded
  88		 * values for full inode chunks.
  89		 */
  90		irec->ir_holemask = XFS_INOBT_HOLEMASK_FULL;
  91		irec->ir_count = XFS_INODES_PER_CHUNK;
  92		irec->ir_freecount =
  93				be32_to_cpu(rec->inobt.ir_u.f.ir_freecount);
  94	}
  95	irec->ir_free = be64_to_cpu(rec->inobt.ir_free);
  96}
  97
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  98/*
  99 * Get the data from the pointed-to record.
 100 */
 101int
 102xfs_inobt_get_rec(
 103	struct xfs_btree_cur		*cur,
 104	struct xfs_inobt_rec_incore	*irec,
 105	int				*stat)
 106{
 107	struct xfs_mount		*mp = cur->bc_mp;
 108	union xfs_btree_rec		*rec;
 
 109	int				error;
 110	uint64_t			realfree;
 111
 112	error = xfs_btree_get_rec(cur, &rec, stat);
 113	if (error || *stat == 0)
 114		return error;
 115
 116	xfs_inobt_btrec_to_irec(mp, rec, irec);
 117
 118	if (!xfs_verify_agino(cur->bc_ag.pag, irec->ir_startino))
 119		goto out_bad_rec;
 120	if (irec->ir_count < XFS_INODES_PER_HOLEMASK_BIT ||
 121	    irec->ir_count > XFS_INODES_PER_CHUNK)
 122		goto out_bad_rec;
 123	if (irec->ir_freecount > XFS_INODES_PER_CHUNK)
 124		goto out_bad_rec;
 125
 126	/* if there are no holes, return the first available offset */
 127	if (!xfs_inobt_issparse(irec->ir_holemask))
 128		realfree = irec->ir_free;
 129	else
 130		realfree = irec->ir_free & xfs_inobt_irec_to_allocmask(irec);
 131	if (hweight64(realfree) != irec->ir_freecount)
 132		goto out_bad_rec;
 133
 134	return 0;
 135
 136out_bad_rec:
 137	xfs_warn(mp,
 138		"%s Inode BTree record corruption in AG %d detected!",
 139		cur->bc_btnum == XFS_BTNUM_INO ? "Used" : "Free",
 140		cur->bc_ag.pag->pag_agno);
 141	xfs_warn(mp,
 142"start inode 0x%x, count 0x%x, free 0x%x freemask 0x%llx, holemask 0x%x",
 143		irec->ir_startino, irec->ir_count, irec->ir_freecount,
 144		irec->ir_free, irec->ir_holemask);
 145	return -EFSCORRUPTED;
 146}
 147
 148/*
 149 * Insert a single inobt record. Cursor must already point to desired location.
 150 */
 151int
 152xfs_inobt_insert_rec(
 153	struct xfs_btree_cur	*cur,
 154	uint16_t		holemask,
 155	uint8_t			count,
 156	int32_t			freecount,
 157	xfs_inofree_t		free,
 158	int			*stat)
 159{
 160	cur->bc_rec.i.ir_holemask = holemask;
 161	cur->bc_rec.i.ir_count = count;
 162	cur->bc_rec.i.ir_freecount = freecount;
 163	cur->bc_rec.i.ir_free = free;
 164	return xfs_btree_insert(cur, stat);
 165}
 166
 167/*
 168 * Insert records describing a newly allocated inode chunk into the inobt.
 169 */
 170STATIC int
 171xfs_inobt_insert(
 172	struct xfs_mount	*mp,
 173	struct xfs_trans	*tp,
 174	struct xfs_buf		*agbp,
 175	struct xfs_perag	*pag,
 176	xfs_agino_t		newino,
 177	xfs_agino_t		newlen,
 178	xfs_btnum_t		btnum)
 179{
 180	struct xfs_btree_cur	*cur;
 181	xfs_agino_t		thisino;
 182	int			i;
 183	int			error;
 184
 185	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, btnum);
 
 
 
 186
 187	for (thisino = newino;
 188	     thisino < newino + newlen;
 189	     thisino += XFS_INODES_PER_CHUNK) {
 190		error = xfs_inobt_lookup(cur, thisino, XFS_LOOKUP_EQ, &i);
 191		if (error) {
 192			xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 193			return error;
 194		}
 195		ASSERT(i == 0);
 196
 197		error = xfs_inobt_insert_rec(cur, XFS_INOBT_HOLEMASK_FULL,
 198					     XFS_INODES_PER_CHUNK,
 199					     XFS_INODES_PER_CHUNK,
 200					     XFS_INOBT_ALL_FREE, &i);
 201		if (error) {
 202			xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 203			return error;
 204		}
 205		ASSERT(i == 1);
 206	}
 207
 208	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 209
 210	return 0;
 211}
 212
 213/*
 214 * Verify that the number of free inodes in the AGI is correct.
 215 */
 216#ifdef DEBUG
 217static int
 218xfs_check_agi_freecount(
 219	struct xfs_btree_cur	*cur)
 220{
 221	if (cur->bc_nlevels == 1) {
 222		xfs_inobt_rec_incore_t rec;
 223		int		freecount = 0;
 224		int		error;
 225		int		i;
 226
 227		error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
 228		if (error)
 229			return error;
 230
 231		do {
 232			error = xfs_inobt_get_rec(cur, &rec, &i);
 233			if (error)
 234				return error;
 235
 236			if (i) {
 237				freecount += rec.ir_freecount;
 238				error = xfs_btree_increment(cur, 0, &i);
 239				if (error)
 240					return error;
 241			}
 242		} while (i == 1);
 243
 244		if (!xfs_is_shutdown(cur->bc_mp))
 245			ASSERT(freecount == cur->bc_ag.pag->pagi_freecount);
 246	}
 247	return 0;
 248}
 249#else
 250#define xfs_check_agi_freecount(cur)	0
 251#endif
 252
 253/*
 254 * Initialise a new set of inodes. When called without a transaction context
 255 * (e.g. from recovery) we initiate a delayed write of the inode buffers rather
 256 * than logging them (which in a transaction context puts them into the AIL
 257 * for writeback rather than the xfsbufd queue).
 258 */
 259int
 260xfs_ialloc_inode_init(
 261	struct xfs_mount	*mp,
 262	struct xfs_trans	*tp,
 263	struct list_head	*buffer_list,
 264	int			icount,
 265	xfs_agnumber_t		agno,
 266	xfs_agblock_t		agbno,
 267	xfs_agblock_t		length,
 268	unsigned int		gen)
 269{
 270	struct xfs_buf		*fbuf;
 271	struct xfs_dinode	*free;
 272	int			nbufs;
 273	int			version;
 274	int			i, j;
 275	xfs_daddr_t		d;
 276	xfs_ino_t		ino = 0;
 277	int			error;
 278
 279	/*
 280	 * Loop over the new block(s), filling in the inodes.  For small block
 281	 * sizes, manipulate the inodes in buffers  which are multiples of the
 282	 * blocks size.
 283	 */
 284	nbufs = length / M_IGEO(mp)->blocks_per_cluster;
 285
 286	/*
 287	 * Figure out what version number to use in the inodes we create.  If
 288	 * the superblock version has caught up to the one that supports the new
 289	 * inode format, then use the new inode version.  Otherwise use the old
 290	 * version so that old kernels will continue to be able to use the file
 291	 * system.
 292	 *
 293	 * For v3 inodes, we also need to write the inode number into the inode,
 294	 * so calculate the first inode number of the chunk here as
 295	 * XFS_AGB_TO_AGINO() only works within a filesystem block, not
 296	 * across multiple filesystem blocks (such as a cluster) and so cannot
 297	 * be used in the cluster buffer loop below.
 298	 *
 299	 * Further, because we are writing the inode directly into the buffer
 300	 * and calculating a CRC on the entire inode, we have ot log the entire
 301	 * inode so that the entire range the CRC covers is present in the log.
 302	 * That means for v3 inode we log the entire buffer rather than just the
 303	 * inode cores.
 304	 */
 305	if (xfs_has_v3inodes(mp)) {
 306		version = 3;
 307		ino = XFS_AGINO_TO_INO(mp, agno, XFS_AGB_TO_AGINO(mp, agbno));
 308
 309		/*
 310		 * log the initialisation that is about to take place as an
 311		 * logical operation. This means the transaction does not
 312		 * need to log the physical changes to the inode buffers as log
 313		 * recovery will know what initialisation is actually needed.
 314		 * Hence we only need to log the buffers as "ordered" buffers so
 315		 * they track in the AIL as if they were physically logged.
 316		 */
 317		if (tp)
 318			xfs_icreate_log(tp, agno, agbno, icount,
 319					mp->m_sb.sb_inodesize, length, gen);
 320	} else
 321		version = 2;
 322
 323	for (j = 0; j < nbufs; j++) {
 324		/*
 325		 * Get the block.
 326		 */
 327		d = XFS_AGB_TO_DADDR(mp, agno, agbno +
 328				(j * M_IGEO(mp)->blocks_per_cluster));
 329		error = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
 330				mp->m_bsize * M_IGEO(mp)->blocks_per_cluster,
 331				XBF_UNMAPPED, &fbuf);
 332		if (error)
 333			return error;
 334
 335		/* Initialize the inode buffers and log them appropriately. */
 336		fbuf->b_ops = &xfs_inode_buf_ops;
 337		xfs_buf_zero(fbuf, 0, BBTOB(fbuf->b_length));
 338		for (i = 0; i < M_IGEO(mp)->inodes_per_cluster; i++) {
 339			int	ioffset = i << mp->m_sb.sb_inodelog;
 340
 341			free = xfs_make_iptr(mp, fbuf, i);
 342			free->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
 343			free->di_version = version;
 344			free->di_gen = cpu_to_be32(gen);
 345			free->di_next_unlinked = cpu_to_be32(NULLAGINO);
 346
 347			if (version == 3) {
 348				free->di_ino = cpu_to_be64(ino);
 349				ino++;
 350				uuid_copy(&free->di_uuid,
 351					  &mp->m_sb.sb_meta_uuid);
 352				xfs_dinode_calc_crc(mp, free);
 353			} else if (tp) {
 354				/* just log the inode core */
 355				xfs_trans_log_buf(tp, fbuf, ioffset,
 356					  ioffset + XFS_DINODE_SIZE(mp) - 1);
 357			}
 358		}
 359
 360		if (tp) {
 361			/*
 362			 * Mark the buffer as an inode allocation buffer so it
 363			 * sticks in AIL at the point of this allocation
 364			 * transaction. This ensures the they are on disk before
 365			 * the tail of the log can be moved past this
 366			 * transaction (i.e. by preventing relogging from moving
 367			 * it forward in the log).
 368			 */
 369			xfs_trans_inode_alloc_buf(tp, fbuf);
 370			if (version == 3) {
 371				/*
 372				 * Mark the buffer as ordered so that they are
 373				 * not physically logged in the transaction but
 374				 * still tracked in the AIL as part of the
 375				 * transaction and pin the log appropriately.
 376				 */
 377				xfs_trans_ordered_buf(tp, fbuf);
 378			}
 379		} else {
 380			fbuf->b_flags |= XBF_DONE;
 381			xfs_buf_delwri_queue(fbuf, buffer_list);
 382			xfs_buf_relse(fbuf);
 383		}
 384	}
 385	return 0;
 386}
 387
 388/*
 389 * Align startino and allocmask for a recently allocated sparse chunk such that
 390 * they are fit for insertion (or merge) into the on-disk inode btrees.
 391 *
 392 * Background:
 393 *
 394 * When enabled, sparse inode support increases the inode alignment from cluster
 395 * size to inode chunk size. This means that the minimum range between two
 396 * non-adjacent inode records in the inobt is large enough for a full inode
 397 * record. This allows for cluster sized, cluster aligned block allocation
 398 * without need to worry about whether the resulting inode record overlaps with
 399 * another record in the tree. Without this basic rule, we would have to deal
 400 * with the consequences of overlap by potentially undoing recent allocations in
 401 * the inode allocation codepath.
 402 *
 403 * Because of this alignment rule (which is enforced on mount), there are two
 404 * inobt possibilities for newly allocated sparse chunks. One is that the
 405 * aligned inode record for the chunk covers a range of inodes not already
 406 * covered in the inobt (i.e., it is safe to insert a new sparse record). The
 407 * other is that a record already exists at the aligned startino that considers
 408 * the newly allocated range as sparse. In the latter case, record content is
 409 * merged in hope that sparse inode chunks fill to full chunks over time.
 410 */
 411STATIC void
 412xfs_align_sparse_ino(
 413	struct xfs_mount		*mp,
 414	xfs_agino_t			*startino,
 415	uint16_t			*allocmask)
 416{
 417	xfs_agblock_t			agbno;
 418	xfs_agblock_t			mod;
 419	int				offset;
 420
 421	agbno = XFS_AGINO_TO_AGBNO(mp, *startino);
 422	mod = agbno % mp->m_sb.sb_inoalignmt;
 423	if (!mod)
 424		return;
 425
 426	/* calculate the inode offset and align startino */
 427	offset = XFS_AGB_TO_AGINO(mp, mod);
 428	*startino -= offset;
 429
 430	/*
 431	 * Since startino has been aligned down, left shift allocmask such that
 432	 * it continues to represent the same physical inodes relative to the
 433	 * new startino.
 434	 */
 435	*allocmask <<= offset / XFS_INODES_PER_HOLEMASK_BIT;
 436}
 437
 438/*
 439 * Determine whether the source inode record can merge into the target. Both
 440 * records must be sparse, the inode ranges must match and there must be no
 441 * allocation overlap between the records.
 442 */
 443STATIC bool
 444__xfs_inobt_can_merge(
 445	struct xfs_inobt_rec_incore	*trec,	/* tgt record */
 446	struct xfs_inobt_rec_incore	*srec)	/* src record */
 447{
 448	uint64_t			talloc;
 449	uint64_t			salloc;
 450
 451	/* records must cover the same inode range */
 452	if (trec->ir_startino != srec->ir_startino)
 453		return false;
 454
 455	/* both records must be sparse */
 456	if (!xfs_inobt_issparse(trec->ir_holemask) ||
 457	    !xfs_inobt_issparse(srec->ir_holemask))
 458		return false;
 459
 460	/* both records must track some inodes */
 461	if (!trec->ir_count || !srec->ir_count)
 462		return false;
 463
 464	/* can't exceed capacity of a full record */
 465	if (trec->ir_count + srec->ir_count > XFS_INODES_PER_CHUNK)
 466		return false;
 467
 468	/* verify there is no allocation overlap */
 469	talloc = xfs_inobt_irec_to_allocmask(trec);
 470	salloc = xfs_inobt_irec_to_allocmask(srec);
 471	if (talloc & salloc)
 472		return false;
 473
 474	return true;
 475}
 476
 477/*
 478 * Merge the source inode record into the target. The caller must call
 479 * __xfs_inobt_can_merge() to ensure the merge is valid.
 480 */
 481STATIC void
 482__xfs_inobt_rec_merge(
 483	struct xfs_inobt_rec_incore	*trec,	/* target */
 484	struct xfs_inobt_rec_incore	*srec)	/* src */
 485{
 486	ASSERT(trec->ir_startino == srec->ir_startino);
 487
 488	/* combine the counts */
 489	trec->ir_count += srec->ir_count;
 490	trec->ir_freecount += srec->ir_freecount;
 491
 492	/*
 493	 * Merge the holemask and free mask. For both fields, 0 bits refer to
 494	 * allocated inodes. We combine the allocated ranges with bitwise AND.
 495	 */
 496	trec->ir_holemask &= srec->ir_holemask;
 497	trec->ir_free &= srec->ir_free;
 498}
 499
 500/*
 501 * Insert a new sparse inode chunk into the associated inode btree. The inode
 502 * record for the sparse chunk is pre-aligned to a startino that should match
 503 * any pre-existing sparse inode record in the tree. This allows sparse chunks
 504 * to fill over time.
 505 *
 506 * This function supports two modes of handling preexisting records depending on
 507 * the merge flag. If merge is true, the provided record is merged with the
 508 * existing record and updated in place. The merged record is returned in nrec.
 509 * If merge is false, an existing record is replaced with the provided record.
 510 * If no preexisting record exists, the provided record is always inserted.
 511 *
 512 * It is considered corruption if a merge is requested and not possible. Given
 513 * the sparse inode alignment constraints, this should never happen.
 514 */
 515STATIC int
 516xfs_inobt_insert_sprec(
 517	struct xfs_mount		*mp,
 518	struct xfs_trans		*tp,
 519	struct xfs_buf			*agbp,
 520	struct xfs_perag		*pag,
 521	int				btnum,
 522	struct xfs_inobt_rec_incore	*nrec,	/* in/out: new/merged rec. */
 523	bool				merge)	/* merge or replace */
 524{
 
 525	struct xfs_btree_cur		*cur;
 526	int				error;
 527	int				i;
 528	struct xfs_inobt_rec_incore	rec;
 529
 530	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, btnum);
 531
 532	/* the new record is pre-aligned so we know where to look */
 533	error = xfs_inobt_lookup(cur, nrec->ir_startino, XFS_LOOKUP_EQ, &i);
 534	if (error)
 535		goto error;
 536	/* if nothing there, insert a new record and return */
 537	if (i == 0) {
 538		error = xfs_inobt_insert_rec(cur, nrec->ir_holemask,
 539					     nrec->ir_count, nrec->ir_freecount,
 540					     nrec->ir_free, &i);
 541		if (error)
 542			goto error;
 543		if (XFS_IS_CORRUPT(mp, i != 1)) {
 
 544			error = -EFSCORRUPTED;
 545			goto error;
 546		}
 547
 548		goto out;
 549	}
 550
 551	/*
 552	 * A record exists at this startino. Merge or replace the record
 553	 * depending on what we've been asked to do.
 554	 */
 555	if (merge) {
 556		error = xfs_inobt_get_rec(cur, &rec, &i);
 557		if (error)
 558			goto error;
 559		if (XFS_IS_CORRUPT(mp, i != 1)) {
 560			error = -EFSCORRUPTED;
 561			goto error;
 562		}
 563		if (XFS_IS_CORRUPT(mp, rec.ir_startino != nrec->ir_startino)) {
 564			error = -EFSCORRUPTED;
 565			goto error;
 566		}
 
 567
 568		/*
 569		 * This should never fail. If we have coexisting records that
 570		 * cannot merge, something is seriously wrong.
 571		 */
 572		if (XFS_IS_CORRUPT(mp, !__xfs_inobt_can_merge(nrec, &rec))) {
 573			error = -EFSCORRUPTED;
 574			goto error;
 575		}
 
 576
 577		trace_xfs_irec_merge_pre(mp, pag->pag_agno, rec.ir_startino,
 578					 rec.ir_holemask, nrec->ir_startino,
 579					 nrec->ir_holemask);
 580
 581		/* merge to nrec to output the updated record */
 582		__xfs_inobt_rec_merge(nrec, &rec);
 583
 584		trace_xfs_irec_merge_post(mp, pag->pag_agno, nrec->ir_startino,
 585					  nrec->ir_holemask);
 586
 587		error = xfs_inobt_rec_check_count(mp, nrec);
 588		if (error)
 589			goto error;
 590	}
 591
 592	error = xfs_inobt_update(cur, nrec);
 593	if (error)
 594		goto error;
 595
 596out:
 597	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 598	return 0;
 599error:
 600	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 601	return error;
 602}
 603
 604/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 605 * Allocate new inodes in the allocation group specified by agbp.  Returns 0 if
 606 * inodes were allocated in this AG; -EAGAIN if there was no space in this AG so
 607 * the caller knows it can try another AG, a hard -ENOSPC when over the maximum
 608 * inode count threshold, or the usual negative error code for other errors.
 609 */
 610STATIC int
 611xfs_ialloc_ag_alloc(
 
 612	struct xfs_trans	*tp,
 613	struct xfs_buf		*agbp,
 614	struct xfs_perag	*pag)
 615{
 616	struct xfs_agi		*agi;
 617	struct xfs_alloc_arg	args;
 618	int			error;
 619	xfs_agino_t		newino;		/* new first inode's number */
 620	xfs_agino_t		newlen;		/* new number of inodes */
 621	int			isaligned = 0;	/* inode allocation at stripe */
 622						/* unit boundary */
 623	/* init. to full chunk */
 624	struct xfs_inobt_rec_incore rec;
 625	struct xfs_ino_geometry	*igeo = M_IGEO(tp->t_mountp);
 626	uint16_t		allocmask = (uint16_t) -1;
 627	int			do_sparse = 0;
 628
 629	memset(&args, 0, sizeof(args));
 630	args.tp = tp;
 631	args.mp = tp->t_mountp;
 632	args.fsbno = NULLFSBLOCK;
 633	args.oinfo = XFS_RMAP_OINFO_INODES;
 
 634
 635#ifdef DEBUG
 636	/* randomly do sparse inode allocations */
 637	if (xfs_has_sparseinodes(tp->t_mountp) &&
 638	    igeo->ialloc_min_blks < igeo->ialloc_blks)
 639		do_sparse = get_random_u32_below(2);
 640#endif
 641
 642	/*
 643	 * Locking will ensure that we don't have two callers in here
 644	 * at one time.
 645	 */
 646	newlen = igeo->ialloc_inos;
 647	if (igeo->maxicount &&
 648	    percpu_counter_read_positive(&args.mp->m_icount) + newlen >
 649							igeo->maxicount)
 650		return -ENOSPC;
 651	args.minlen = args.maxlen = igeo->ialloc_blks;
 652	/*
 653	 * First try to allocate inodes contiguous with the last-allocated
 654	 * chunk of inodes.  If the filesystem is striped, this will fill
 655	 * an entire stripe unit with inodes.
 656	 */
 657	agi = agbp->b_addr;
 658	newino = be32_to_cpu(agi->agi_newino);
 659	args.agbno = XFS_AGINO_TO_AGBNO(args.mp, newino) +
 660		     igeo->ialloc_blks;
 661	if (do_sparse)
 662		goto sparse_alloc;
 663	if (likely(newino != NULLAGINO &&
 664		  (args.agbno < be32_to_cpu(agi->agi_length)))) {
 665		args.fsbno = XFS_AGB_TO_FSB(args.mp, pag->pag_agno, args.agbno);
 666		args.type = XFS_ALLOCTYPE_THIS_BNO;
 667		args.prod = 1;
 668
 669		/*
 670		 * We need to take into account alignment here to ensure that
 671		 * we don't modify the free list if we fail to have an exact
 672		 * block. If we don't have an exact match, and every oher
 673		 * attempt allocation attempt fails, we'll end up cancelling
 674		 * a dirty transaction and shutting down.
 675		 *
 676		 * For an exact allocation, alignment must be 1,
 677		 * however we need to take cluster alignment into account when
 678		 * fixing up the freelist. Use the minalignslop field to
 679		 * indicate that extra blocks might be required for alignment,
 680		 * but not to use them in the actual exact allocation.
 681		 */
 682		args.alignment = 1;
 683		args.minalignslop = igeo->cluster_align - 1;
 684
 685		/* Allow space for the inode btree to split. */
 686		args.minleft = igeo->inobt_maxlevels;
 687		if ((error = xfs_alloc_vextent(&args)))
 
 
 
 688			return error;
 689
 690		/*
 691		 * This request might have dirtied the transaction if the AG can
 692		 * satisfy the request, but the exact block was not available.
 693		 * If the allocation did fail, subsequent requests will relax
 694		 * the exact agbno requirement and increase the alignment
 695		 * instead. It is critical that the total size of the request
 696		 * (len + alignment + slop) does not increase from this point
 697		 * on, so reset minalignslop to ensure it is not included in
 698		 * subsequent requests.
 699		 */
 700		args.minalignslop = 0;
 701	}
 702
 703	if (unlikely(args.fsbno == NULLFSBLOCK)) {
 704		/*
 705		 * Set the alignment for the allocation.
 706		 * If stripe alignment is turned on then align at stripe unit
 707		 * boundary.
 708		 * If the cluster size is smaller than a filesystem block
 709		 * then we're doing I/O for inodes in filesystem block size
 710		 * pieces, so don't need alignment anyway.
 711		 */
 712		isaligned = 0;
 713		if (igeo->ialloc_align) {
 714			ASSERT(!xfs_has_noalign(args.mp));
 715			args.alignment = args.mp->m_dalign;
 716			isaligned = 1;
 717		} else
 718			args.alignment = igeo->cluster_align;
 719		/*
 720		 * Need to figure out where to allocate the inode blocks.
 721		 * Ideally they should be spaced out through the a.g.
 722		 * For now, just allocate blocks up front.
 723		 */
 724		args.agbno = be32_to_cpu(agi->agi_root);
 725		args.fsbno = XFS_AGB_TO_FSB(args.mp, pag->pag_agno, args.agbno);
 726		/*
 727		 * Allocate a fixed-size extent of inodes.
 728		 */
 729		args.type = XFS_ALLOCTYPE_NEAR_BNO;
 730		args.prod = 1;
 731		/*
 732		 * Allow space for the inode btree to split.
 733		 */
 734		args.minleft = igeo->inobt_maxlevels;
 735		if ((error = xfs_alloc_vextent(&args)))
 
 
 
 736			return error;
 737	}
 738
 739	/*
 740	 * If stripe alignment is turned on, then try again with cluster
 741	 * alignment.
 742	 */
 743	if (isaligned && args.fsbno == NULLFSBLOCK) {
 744		args.type = XFS_ALLOCTYPE_NEAR_BNO;
 745		args.agbno = be32_to_cpu(agi->agi_root);
 746		args.fsbno = XFS_AGB_TO_FSB(args.mp, pag->pag_agno, args.agbno);
 747		args.alignment = igeo->cluster_align;
 748		if ((error = xfs_alloc_vextent(&args)))
 
 
 
 749			return error;
 750	}
 751
 752	/*
 753	 * Finally, try a sparse allocation if the filesystem supports it and
 754	 * the sparse allocation length is smaller than a full chunk.
 755	 */
 756	if (xfs_has_sparseinodes(args.mp) &&
 757	    igeo->ialloc_min_blks < igeo->ialloc_blks &&
 758	    args.fsbno == NULLFSBLOCK) {
 759sparse_alloc:
 760		args.type = XFS_ALLOCTYPE_NEAR_BNO;
 761		args.agbno = be32_to_cpu(agi->agi_root);
 762		args.fsbno = XFS_AGB_TO_FSB(args.mp, pag->pag_agno, args.agbno);
 763		args.alignment = args.mp->m_sb.sb_spino_align;
 764		args.prod = 1;
 765
 766		args.minlen = igeo->ialloc_min_blks;
 767		args.maxlen = args.minlen;
 768
 769		/*
 770		 * The inode record will be aligned to full chunk size. We must
 771		 * prevent sparse allocation from AG boundaries that result in
 772		 * invalid inode records, such as records that start at agbno 0
 773		 * or extend beyond the AG.
 774		 *
 775		 * Set min agbno to the first aligned, non-zero agbno and max to
 776		 * the last aligned agbno that is at least one full chunk from
 777		 * the end of the AG.
 778		 */
 779		args.min_agbno = args.mp->m_sb.sb_inoalignmt;
 780		args.max_agbno = round_down(args.mp->m_sb.sb_agblocks,
 781					    args.mp->m_sb.sb_inoalignmt) -
 782				 igeo->ialloc_blks;
 783
 784		error = xfs_alloc_vextent(&args);
 
 
 785		if (error)
 786			return error;
 787
 788		newlen = XFS_AGB_TO_AGINO(args.mp, args.len);
 789		ASSERT(newlen <= XFS_INODES_PER_CHUNK);
 790		allocmask = (1 << (newlen / XFS_INODES_PER_HOLEMASK_BIT)) - 1;
 791	}
 792
 793	if (args.fsbno == NULLFSBLOCK)
 794		return -EAGAIN;
 795
 796	ASSERT(args.len == args.minlen);
 797
 798	/*
 799	 * Stamp and write the inode buffers.
 800	 *
 801	 * Seed the new inode cluster with a random generation number. This
 802	 * prevents short-term reuse of generation numbers if a chunk is
 803	 * freed and then immediately reallocated. We use random numbers
 804	 * rather than a linear progression to prevent the next generation
 805	 * number from being easily guessable.
 806	 */
 807	error = xfs_ialloc_inode_init(args.mp, tp, NULL, newlen, pag->pag_agno,
 808			args.agbno, args.len, get_random_u32());
 809
 810	if (error)
 811		return error;
 812	/*
 813	 * Convert the results.
 814	 */
 815	newino = XFS_AGB_TO_AGINO(args.mp, args.agbno);
 816
 817	if (xfs_inobt_issparse(~allocmask)) {
 818		/*
 819		 * We've allocated a sparse chunk. Align the startino and mask.
 820		 */
 821		xfs_align_sparse_ino(args.mp, &newino, &allocmask);
 822
 823		rec.ir_startino = newino;
 824		rec.ir_holemask = ~allocmask;
 825		rec.ir_count = newlen;
 826		rec.ir_freecount = newlen;
 827		rec.ir_free = XFS_INOBT_ALL_FREE;
 828
 829		/*
 830		 * Insert the sparse record into the inobt and allow for a merge
 831		 * if necessary. If a merge does occur, rec is updated to the
 832		 * merged record.
 833		 */
 834		error = xfs_inobt_insert_sprec(args.mp, tp, agbp, pag,
 835				XFS_BTNUM_INO, &rec, true);
 836		if (error == -EFSCORRUPTED) {
 837			xfs_alert(args.mp,
 838	"invalid sparse inode record: ino 0x%llx holemask 0x%x count %u",
 839				  XFS_AGINO_TO_INO(args.mp, pag->pag_agno,
 840						   rec.ir_startino),
 841				  rec.ir_holemask, rec.ir_count);
 842			xfs_force_shutdown(args.mp, SHUTDOWN_CORRUPT_INCORE);
 843		}
 844		if (error)
 845			return error;
 846
 847		/*
 848		 * We can't merge the part we've just allocated as for the inobt
 849		 * due to finobt semantics. The original record may or may not
 850		 * exist independent of whether physical inodes exist in this
 851		 * sparse chunk.
 852		 *
 853		 * We must update the finobt record based on the inobt record.
 854		 * rec contains the fully merged and up to date inobt record
 855		 * from the previous call. Set merge false to replace any
 856		 * existing record with this one.
 857		 */
 858		if (xfs_has_finobt(args.mp)) {
 859			error = xfs_inobt_insert_sprec(args.mp, tp, agbp, pag,
 860				       XFS_BTNUM_FINO, &rec, false);
 861			if (error)
 862				return error;
 863		}
 864	} else {
 865		/* full chunk - insert new records to both btrees */
 866		error = xfs_inobt_insert(args.mp, tp, agbp, pag, newino, newlen,
 867					 XFS_BTNUM_INO);
 868		if (error)
 869			return error;
 870
 871		if (xfs_has_finobt(args.mp)) {
 872			error = xfs_inobt_insert(args.mp, tp, agbp, pag, newino,
 873						 newlen, XFS_BTNUM_FINO);
 874			if (error)
 875				return error;
 876		}
 877	}
 878
 879	/*
 880	 * Update AGI counts and newino.
 881	 */
 882	be32_add_cpu(&agi->agi_count, newlen);
 883	be32_add_cpu(&agi->agi_freecount, newlen);
 884	pag->pagi_freecount += newlen;
 885	pag->pagi_count += newlen;
 886	agi->agi_newino = cpu_to_be32(newino);
 887
 888	/*
 889	 * Log allocation group header fields
 890	 */
 891	xfs_ialloc_log_agi(tp, agbp,
 892		XFS_AGI_COUNT | XFS_AGI_FREECOUNT | XFS_AGI_NEWINO);
 893	/*
 894	 * Modify/log superblock values for inode count and inode free count.
 895	 */
 896	xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, (long)newlen);
 897	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, (long)newlen);
 898	return 0;
 899}
 900
 901/*
 902 * Try to retrieve the next record to the left/right from the current one.
 903 */
 904STATIC int
 905xfs_ialloc_next_rec(
 906	struct xfs_btree_cur	*cur,
 907	xfs_inobt_rec_incore_t	*rec,
 908	int			*done,
 909	int			left)
 910{
 911	int                     error;
 912	int			i;
 913
 914	if (left)
 915		error = xfs_btree_decrement(cur, 0, &i);
 916	else
 917		error = xfs_btree_increment(cur, 0, &i);
 918
 919	if (error)
 920		return error;
 921	*done = !i;
 922	if (i) {
 923		error = xfs_inobt_get_rec(cur, rec, &i);
 924		if (error)
 925			return error;
 926		if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
 
 927			return -EFSCORRUPTED;
 
 928	}
 929
 930	return 0;
 931}
 932
 933STATIC int
 934xfs_ialloc_get_rec(
 935	struct xfs_btree_cur	*cur,
 936	xfs_agino_t		agino,
 937	xfs_inobt_rec_incore_t	*rec,
 938	int			*done)
 939{
 940	int                     error;
 941	int			i;
 942
 943	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_EQ, &i);
 944	if (error)
 945		return error;
 946	*done = !i;
 947	if (i) {
 948		error = xfs_inobt_get_rec(cur, rec, &i);
 949		if (error)
 950			return error;
 951		if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
 
 952			return -EFSCORRUPTED;
 
 953	}
 954
 955	return 0;
 956}
 957
 958/*
 959 * Return the offset of the first free inode in the record. If the inode chunk
 960 * is sparsely allocated, we convert the record holemask to inode granularity
 961 * and mask off the unallocated regions from the inode free mask.
 962 */
 963STATIC int
 964xfs_inobt_first_free_inode(
 965	struct xfs_inobt_rec_incore	*rec)
 966{
 967	xfs_inofree_t			realfree;
 968
 969	/* if there are no holes, return the first available offset */
 970	if (!xfs_inobt_issparse(rec->ir_holemask))
 971		return xfs_lowbit64(rec->ir_free);
 972
 973	realfree = xfs_inobt_irec_to_allocmask(rec);
 974	realfree &= rec->ir_free;
 975
 976	return xfs_lowbit64(realfree);
 977}
 978
 979/*
 980 * Allocate an inode using the inobt-only algorithm.
 981 */
 982STATIC int
 983xfs_dialloc_ag_inobt(
 
 984	struct xfs_trans	*tp,
 985	struct xfs_buf		*agbp,
 986	struct xfs_perag	*pag,
 987	xfs_ino_t		parent,
 988	xfs_ino_t		*inop)
 989{
 990	struct xfs_mount	*mp = tp->t_mountp;
 991	struct xfs_agi		*agi = agbp->b_addr;
 992	xfs_agnumber_t		pagno = XFS_INO_TO_AGNO(mp, parent);
 993	xfs_agino_t		pagino = XFS_INO_TO_AGINO(mp, parent);
 994	struct xfs_btree_cur	*cur, *tcur;
 995	struct xfs_inobt_rec_incore rec, trec;
 996	xfs_ino_t		ino;
 997	int			error;
 998	int			offset;
 999	int			i, j;
1000	int			searchdistance = 10;
1001
1002	ASSERT(pag->pagi_init);
1003	ASSERT(pag->pagi_inodeok);
1004	ASSERT(pag->pagi_freecount > 0);
1005
1006 restart_pagno:
1007	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_INO);
1008	/*
1009	 * If pagino is 0 (this is the root inode allocation) use newino.
1010	 * This must work because we've just allocated some.
1011	 */
1012	if (!pagino)
1013		pagino = be32_to_cpu(agi->agi_newino);
1014
1015	error = xfs_check_agi_freecount(cur);
1016	if (error)
1017		goto error0;
1018
1019	/*
1020	 * If in the same AG as the parent, try to get near the parent.
1021	 */
1022	if (pagno == pag->pag_agno) {
1023		int		doneleft;	/* done, to the left */
1024		int		doneright;	/* done, to the right */
1025
1026		error = xfs_inobt_lookup(cur, pagino, XFS_LOOKUP_LE, &i);
1027		if (error)
1028			goto error0;
1029		if (XFS_IS_CORRUPT(mp, i != 1)) {
 
1030			error = -EFSCORRUPTED;
1031			goto error0;
1032		}
1033
1034		error = xfs_inobt_get_rec(cur, &rec, &j);
1035		if (error)
1036			goto error0;
1037		if (XFS_IS_CORRUPT(mp, j != 1)) {
 
1038			error = -EFSCORRUPTED;
1039			goto error0;
1040		}
1041
1042		if (rec.ir_freecount > 0) {
1043			/*
1044			 * Found a free inode in the same chunk
1045			 * as the parent, done.
1046			 */
1047			goto alloc_inode;
1048		}
1049
1050
1051		/*
1052		 * In the same AG as parent, but parent's chunk is full.
1053		 */
1054
1055		/* duplicate the cursor, search left & right simultaneously */
1056		error = xfs_btree_dup_cursor(cur, &tcur);
1057		if (error)
1058			goto error0;
1059
1060		/*
1061		 * Skip to last blocks looked up if same parent inode.
1062		 */
1063		if (pagino != NULLAGINO &&
1064		    pag->pagl_pagino == pagino &&
1065		    pag->pagl_leftrec != NULLAGINO &&
1066		    pag->pagl_rightrec != NULLAGINO) {
1067			error = xfs_ialloc_get_rec(tcur, pag->pagl_leftrec,
1068						   &trec, &doneleft);
1069			if (error)
1070				goto error1;
1071
1072			error = xfs_ialloc_get_rec(cur, pag->pagl_rightrec,
1073						   &rec, &doneright);
1074			if (error)
1075				goto error1;
1076		} else {
1077			/* search left with tcur, back up 1 record */
1078			error = xfs_ialloc_next_rec(tcur, &trec, &doneleft, 1);
1079			if (error)
1080				goto error1;
1081
1082			/* search right with cur, go forward 1 record. */
1083			error = xfs_ialloc_next_rec(cur, &rec, &doneright, 0);
1084			if (error)
1085				goto error1;
1086		}
1087
1088		/*
1089		 * Loop until we find an inode chunk with a free inode.
1090		 */
1091		while (--searchdistance > 0 && (!doneleft || !doneright)) {
1092			int	useleft;  /* using left inode chunk this time */
1093
1094			/* figure out the closer block if both are valid. */
1095			if (!doneleft && !doneright) {
1096				useleft = pagino -
1097				 (trec.ir_startino + XFS_INODES_PER_CHUNK - 1) <
1098				  rec.ir_startino - pagino;
1099			} else {
1100				useleft = !doneleft;
1101			}
1102
1103			/* free inodes to the left? */
1104			if (useleft && trec.ir_freecount) {
1105				xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1106				cur = tcur;
1107
1108				pag->pagl_leftrec = trec.ir_startino;
1109				pag->pagl_rightrec = rec.ir_startino;
1110				pag->pagl_pagino = pagino;
1111				rec = trec;
1112				goto alloc_inode;
1113			}
1114
1115			/* free inodes to the right? */
1116			if (!useleft && rec.ir_freecount) {
1117				xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1118
1119				pag->pagl_leftrec = trec.ir_startino;
1120				pag->pagl_rightrec = rec.ir_startino;
1121				pag->pagl_pagino = pagino;
1122				goto alloc_inode;
1123			}
1124
1125			/* get next record to check */
1126			if (useleft) {
1127				error = xfs_ialloc_next_rec(tcur, &trec,
1128								 &doneleft, 1);
1129			} else {
1130				error = xfs_ialloc_next_rec(cur, &rec,
1131								 &doneright, 0);
1132			}
1133			if (error)
1134				goto error1;
1135		}
1136
1137		if (searchdistance <= 0) {
1138			/*
1139			 * Not in range - save last search
1140			 * location and allocate a new inode
1141			 */
1142			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1143			pag->pagl_leftrec = trec.ir_startino;
1144			pag->pagl_rightrec = rec.ir_startino;
1145			pag->pagl_pagino = pagino;
1146
1147		} else {
1148			/*
1149			 * We've reached the end of the btree. because
1150			 * we are only searching a small chunk of the
1151			 * btree each search, there is obviously free
1152			 * inodes closer to the parent inode than we
1153			 * are now. restart the search again.
1154			 */
1155			pag->pagl_pagino = NULLAGINO;
1156			pag->pagl_leftrec = NULLAGINO;
1157			pag->pagl_rightrec = NULLAGINO;
1158			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1159			xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1160			goto restart_pagno;
1161		}
1162	}
1163
1164	/*
1165	 * In a different AG from the parent.
1166	 * See if the most recently allocated block has any free.
1167	 */
1168	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1169		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1170					 XFS_LOOKUP_EQ, &i);
1171		if (error)
1172			goto error0;
1173
1174		if (i == 1) {
1175			error = xfs_inobt_get_rec(cur, &rec, &j);
1176			if (error)
1177				goto error0;
1178
1179			if (j == 1 && rec.ir_freecount > 0) {
1180				/*
1181				 * The last chunk allocated in the group
1182				 * still has a free inode.
1183				 */
1184				goto alloc_inode;
1185			}
1186		}
1187	}
1188
1189	/*
1190	 * None left in the last group, search the whole AG
1191	 */
1192	error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1193	if (error)
1194		goto error0;
1195	if (XFS_IS_CORRUPT(mp, i != 1)) {
 
1196		error = -EFSCORRUPTED;
1197		goto error0;
1198	}
1199
1200	for (;;) {
1201		error = xfs_inobt_get_rec(cur, &rec, &i);
1202		if (error)
1203			goto error0;
1204		if (XFS_IS_CORRUPT(mp, i != 1)) {
 
1205			error = -EFSCORRUPTED;
1206			goto error0;
1207		}
1208		if (rec.ir_freecount > 0)
1209			break;
1210		error = xfs_btree_increment(cur, 0, &i);
1211		if (error)
1212			goto error0;
1213		if (XFS_IS_CORRUPT(mp, i != 1)) {
 
1214			error = -EFSCORRUPTED;
1215			goto error0;
1216		}
1217	}
1218
1219alloc_inode:
1220	offset = xfs_inobt_first_free_inode(&rec);
1221	ASSERT(offset >= 0);
1222	ASSERT(offset < XFS_INODES_PER_CHUNK);
1223	ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1224				   XFS_INODES_PER_CHUNK) == 0);
1225	ino = XFS_AGINO_TO_INO(mp, pag->pag_agno, rec.ir_startino + offset);
1226	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1227	rec.ir_freecount--;
1228	error = xfs_inobt_update(cur, &rec);
1229	if (error)
1230		goto error0;
1231	be32_add_cpu(&agi->agi_freecount, -1);
1232	xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1233	pag->pagi_freecount--;
1234
1235	error = xfs_check_agi_freecount(cur);
1236	if (error)
1237		goto error0;
1238
1239	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1240	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1241	*inop = ino;
1242	return 0;
1243error1:
1244	xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
1245error0:
1246	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1247	return error;
1248}
1249
1250/*
1251 * Use the free inode btree to allocate an inode based on distance from the
1252 * parent. Note that the provided cursor may be deleted and replaced.
1253 */
1254STATIC int
1255xfs_dialloc_ag_finobt_near(
1256	xfs_agino_t			pagino,
1257	struct xfs_btree_cur		**ocur,
1258	struct xfs_inobt_rec_incore	*rec)
1259{
1260	struct xfs_btree_cur		*lcur = *ocur;	/* left search cursor */
1261	struct xfs_btree_cur		*rcur;	/* right search cursor */
1262	struct xfs_inobt_rec_incore	rrec;
1263	int				error;
1264	int				i, j;
1265
1266	error = xfs_inobt_lookup(lcur, pagino, XFS_LOOKUP_LE, &i);
1267	if (error)
1268		return error;
1269
1270	if (i == 1) {
1271		error = xfs_inobt_get_rec(lcur, rec, &i);
1272		if (error)
1273			return error;
1274		if (XFS_IS_CORRUPT(lcur->bc_mp, i != 1))
 
1275			return -EFSCORRUPTED;
 
1276
1277		/*
1278		 * See if we've landed in the parent inode record. The finobt
1279		 * only tracks chunks with at least one free inode, so record
1280		 * existence is enough.
1281		 */
1282		if (pagino >= rec->ir_startino &&
1283		    pagino < (rec->ir_startino + XFS_INODES_PER_CHUNK))
1284			return 0;
1285	}
1286
1287	error = xfs_btree_dup_cursor(lcur, &rcur);
1288	if (error)
1289		return error;
1290
1291	error = xfs_inobt_lookup(rcur, pagino, XFS_LOOKUP_GE, &j);
1292	if (error)
1293		goto error_rcur;
1294	if (j == 1) {
1295		error = xfs_inobt_get_rec(rcur, &rrec, &j);
1296		if (error)
1297			goto error_rcur;
1298		if (XFS_IS_CORRUPT(lcur->bc_mp, j != 1)) {
 
1299			error = -EFSCORRUPTED;
1300			goto error_rcur;
1301		}
1302	}
1303
1304	if (XFS_IS_CORRUPT(lcur->bc_mp, i != 1 && j != 1)) {
 
1305		error = -EFSCORRUPTED;
1306		goto error_rcur;
1307	}
1308	if (i == 1 && j == 1) {
1309		/*
1310		 * Both the left and right records are valid. Choose the closer
1311		 * inode chunk to the target.
1312		 */
1313		if ((pagino - rec->ir_startino + XFS_INODES_PER_CHUNK - 1) >
1314		    (rrec.ir_startino - pagino)) {
1315			*rec = rrec;
1316			xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1317			*ocur = rcur;
1318		} else {
1319			xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1320		}
1321	} else if (j == 1) {
1322		/* only the right record is valid */
1323		*rec = rrec;
1324		xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1325		*ocur = rcur;
1326	} else if (i == 1) {
1327		/* only the left record is valid */
1328		xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1329	}
1330
1331	return 0;
1332
1333error_rcur:
1334	xfs_btree_del_cursor(rcur, XFS_BTREE_ERROR);
1335	return error;
1336}
1337
1338/*
1339 * Use the free inode btree to find a free inode based on a newino hint. If
1340 * the hint is NULL, find the first free inode in the AG.
1341 */
1342STATIC int
1343xfs_dialloc_ag_finobt_newino(
1344	struct xfs_agi			*agi,
1345	struct xfs_btree_cur		*cur,
1346	struct xfs_inobt_rec_incore	*rec)
1347{
1348	int error;
1349	int i;
1350
1351	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1352		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1353					 XFS_LOOKUP_EQ, &i);
1354		if (error)
1355			return error;
1356		if (i == 1) {
1357			error = xfs_inobt_get_rec(cur, rec, &i);
1358			if (error)
1359				return error;
1360			if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
 
1361				return -EFSCORRUPTED;
 
1362			return 0;
1363		}
1364	}
1365
1366	/*
1367	 * Find the first inode available in the AG.
1368	 */
1369	error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1370	if (error)
1371		return error;
1372	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
 
1373		return -EFSCORRUPTED;
 
1374
1375	error = xfs_inobt_get_rec(cur, rec, &i);
1376	if (error)
1377		return error;
1378	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
 
1379		return -EFSCORRUPTED;
 
1380
1381	return 0;
1382}
1383
1384/*
1385 * Update the inobt based on a modification made to the finobt. Also ensure that
1386 * the records from both trees are equivalent post-modification.
1387 */
1388STATIC int
1389xfs_dialloc_ag_update_inobt(
1390	struct xfs_btree_cur		*cur,	/* inobt cursor */
1391	struct xfs_inobt_rec_incore	*frec,	/* finobt record */
1392	int				offset) /* inode offset */
1393{
1394	struct xfs_inobt_rec_incore	rec;
1395	int				error;
1396	int				i;
1397
1398	error = xfs_inobt_lookup(cur, frec->ir_startino, XFS_LOOKUP_EQ, &i);
1399	if (error)
1400		return error;
1401	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
 
1402		return -EFSCORRUPTED;
 
1403
1404	error = xfs_inobt_get_rec(cur, &rec, &i);
1405	if (error)
1406		return error;
1407	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
 
1408		return -EFSCORRUPTED;
 
1409	ASSERT((XFS_AGINO_TO_OFFSET(cur->bc_mp, rec.ir_startino) %
1410				   XFS_INODES_PER_CHUNK) == 0);
1411
1412	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1413	rec.ir_freecount--;
1414
1415	if (XFS_IS_CORRUPT(cur->bc_mp,
1416			   rec.ir_free != frec->ir_free ||
1417			   rec.ir_freecount != frec->ir_freecount))
 
1418		return -EFSCORRUPTED;
 
1419
1420	return xfs_inobt_update(cur, &rec);
1421}
1422
1423/*
1424 * Allocate an inode using the free inode btree, if available. Otherwise, fall
1425 * back to the inobt search algorithm.
1426 *
1427 * The caller selected an AG for us, and made sure that free inodes are
1428 * available.
1429 */
1430static int
1431xfs_dialloc_ag(
 
1432	struct xfs_trans	*tp,
1433	struct xfs_buf		*agbp,
1434	struct xfs_perag	*pag,
1435	xfs_ino_t		parent,
1436	xfs_ino_t		*inop)
1437{
1438	struct xfs_mount		*mp = tp->t_mountp;
1439	struct xfs_agi			*agi = agbp->b_addr;
1440	xfs_agnumber_t			pagno = XFS_INO_TO_AGNO(mp, parent);
1441	xfs_agino_t			pagino = XFS_INO_TO_AGINO(mp, parent);
1442	struct xfs_btree_cur		*cur;	/* finobt cursor */
1443	struct xfs_btree_cur		*icur;	/* inobt cursor */
1444	struct xfs_inobt_rec_incore	rec;
1445	xfs_ino_t			ino;
1446	int				error;
1447	int				offset;
1448	int				i;
1449
1450	if (!xfs_has_finobt(mp))
1451		return xfs_dialloc_ag_inobt(tp, agbp, pag, parent, inop);
1452
1453	/*
1454	 * If pagino is 0 (this is the root inode allocation) use newino.
1455	 * This must work because we've just allocated some.
1456	 */
1457	if (!pagino)
1458		pagino = be32_to_cpu(agi->agi_newino);
1459
1460	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_FINO);
1461
1462	error = xfs_check_agi_freecount(cur);
1463	if (error)
1464		goto error_cur;
1465
1466	/*
1467	 * The search algorithm depends on whether we're in the same AG as the
1468	 * parent. If so, find the closest available inode to the parent. If
1469	 * not, consider the agi hint or find the first free inode in the AG.
1470	 */
1471	if (pag->pag_agno == pagno)
1472		error = xfs_dialloc_ag_finobt_near(pagino, &cur, &rec);
1473	else
1474		error = xfs_dialloc_ag_finobt_newino(agi, cur, &rec);
1475	if (error)
1476		goto error_cur;
1477
1478	offset = xfs_inobt_first_free_inode(&rec);
1479	ASSERT(offset >= 0);
1480	ASSERT(offset < XFS_INODES_PER_CHUNK);
1481	ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1482				   XFS_INODES_PER_CHUNK) == 0);
1483	ino = XFS_AGINO_TO_INO(mp, pag->pag_agno, rec.ir_startino + offset);
1484
1485	/*
1486	 * Modify or remove the finobt record.
1487	 */
1488	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1489	rec.ir_freecount--;
1490	if (rec.ir_freecount)
1491		error = xfs_inobt_update(cur, &rec);
1492	else
1493		error = xfs_btree_delete(cur, &i);
1494	if (error)
1495		goto error_cur;
1496
1497	/*
1498	 * The finobt has now been updated appropriately. We haven't updated the
1499	 * agi and superblock yet, so we can create an inobt cursor and validate
1500	 * the original freecount. If all is well, make the equivalent update to
1501	 * the inobt using the finobt record and offset information.
1502	 */
1503	icur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_INO);
1504
1505	error = xfs_check_agi_freecount(icur);
1506	if (error)
1507		goto error_icur;
1508
1509	error = xfs_dialloc_ag_update_inobt(icur, &rec, offset);
1510	if (error)
1511		goto error_icur;
1512
1513	/*
1514	 * Both trees have now been updated. We must update the perag and
1515	 * superblock before we can check the freecount for each btree.
1516	 */
1517	be32_add_cpu(&agi->agi_freecount, -1);
1518	xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1519	pag->pagi_freecount--;
1520
1521	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1522
1523	error = xfs_check_agi_freecount(icur);
1524	if (error)
1525		goto error_icur;
1526	error = xfs_check_agi_freecount(cur);
1527	if (error)
1528		goto error_icur;
1529
1530	xfs_btree_del_cursor(icur, XFS_BTREE_NOERROR);
1531	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1532	*inop = ino;
1533	return 0;
1534
1535error_icur:
1536	xfs_btree_del_cursor(icur, XFS_BTREE_ERROR);
1537error_cur:
1538	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1539	return error;
1540}
1541
1542static int
1543xfs_dialloc_roll(
1544	struct xfs_trans	**tpp,
1545	struct xfs_buf		*agibp)
1546{
1547	struct xfs_trans	*tp = *tpp;
1548	struct xfs_dquot_acct	*dqinfo;
1549	int			error;
1550
1551	/*
1552	 * Hold to on to the agibp across the commit so no other allocation can
1553	 * come in and take the free inodes we just allocated for our caller.
1554	 */
1555	xfs_trans_bhold(tp, agibp);
1556
1557	/*
1558	 * We want the quota changes to be associated with the next transaction,
1559	 * NOT this one. So, detach the dqinfo from this and attach it to the
1560	 * next transaction.
1561	 */
1562	dqinfo = tp->t_dqinfo;
1563	tp->t_dqinfo = NULL;
1564
1565	error = xfs_trans_roll(&tp);
1566
1567	/* Re-attach the quota info that we detached from prev trx. */
1568	tp->t_dqinfo = dqinfo;
1569
1570	/*
1571	 * Join the buffer even on commit error so that the buffer is released
1572	 * when the caller cancels the transaction and doesn't have to handle
1573	 * this error case specially.
1574	 */
1575	xfs_trans_bjoin(tp, agibp);
1576	*tpp = tp;
1577	return error;
1578}
1579
1580static xfs_agnumber_t
1581xfs_ialloc_next_ag(
1582	xfs_mount_t	*mp)
1583{
1584	xfs_agnumber_t	agno;
1585
1586	spin_lock(&mp->m_agirotor_lock);
1587	agno = mp->m_agirotor;
1588	if (++mp->m_agirotor >= mp->m_maxagi)
1589		mp->m_agirotor = 0;
1590	spin_unlock(&mp->m_agirotor_lock);
1591
1592	return agno;
1593}
1594
1595static bool
1596xfs_dialloc_good_ag(
1597	struct xfs_trans	*tp,
1598	struct xfs_perag	*pag,
 
1599	umode_t			mode,
1600	int			flags,
1601	bool			ok_alloc)
1602{
1603	struct xfs_mount	*mp = tp->t_mountp;
1604	xfs_extlen_t		ineed;
1605	xfs_extlen_t		longest = 0;
1606	int			needspace;
1607	int			error;
1608
1609	if (!pag->pagi_inodeok)
 
 
1610		return false;
1611
1612	if (!pag->pagi_init) {
1613		error = xfs_ialloc_read_agi(pag, tp, NULL);
1614		if (error)
1615			return false;
1616	}
1617
1618	if (pag->pagi_freecount)
1619		return true;
1620	if (!ok_alloc)
1621		return false;
1622
1623	if (!pag->pagf_init) {
1624		error = xfs_alloc_read_agf(pag, tp, flags, NULL);
1625		if (error)
1626			return false;
1627	}
1628
1629	/*
1630	 * Check that there is enough free space for the file plus a chunk of
1631	 * inodes if we need to allocate some. If this is the first pass across
1632	 * the AGs, take into account the potential space needed for alignment
1633	 * of inode chunks when checking the longest contiguous free space in
1634	 * the AG - this prevents us from getting ENOSPC because we have free
1635	 * space larger than ialloc_blks but alignment constraints prevent us
1636	 * from using it.
1637	 *
1638	 * If we can't find an AG with space for full alignment slack to be
1639	 * taken into account, we must be near ENOSPC in all AGs.  Hence we
1640	 * don't include alignment for the second pass and so if we fail
1641	 * allocation due to alignment issues then it is most likely a real
1642	 * ENOSPC condition.
1643	 *
1644	 * XXX(dgc): this calculation is now bogus thanks to the per-ag
1645	 * reservations that xfs_alloc_fix_freelist() now does via
1646	 * xfs_alloc_space_available(). When the AG fills up, pagf_freeblks will
1647	 * be more than large enough for the check below to succeed, but
1648	 * xfs_alloc_space_available() will fail because of the non-zero
1649	 * metadata reservation and hence we won't actually be able to allocate
1650	 * more inodes in this AG. We do soooo much unnecessary work near ENOSPC
1651	 * because of this.
1652	 */
1653	ineed = M_IGEO(mp)->ialloc_min_blks;
1654	if (flags && ineed > 1)
1655		ineed += M_IGEO(mp)->cluster_align;
1656	longest = pag->pagf_longest;
1657	if (!longest)
1658		longest = pag->pagf_flcount > 0;
1659	needspace = S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode);
1660
1661	if (pag->pagf_freeblks < needspace + ineed || longest < ineed)
1662		return false;
1663	return true;
1664}
1665
1666static int
1667xfs_dialloc_try_ag(
1668	struct xfs_trans	**tpp,
1669	struct xfs_perag	*pag,
 
1670	xfs_ino_t		parent,
1671	xfs_ino_t		*new_ino,
1672	bool			ok_alloc)
1673{
1674	struct xfs_buf		*agbp;
1675	xfs_ino_t		ino;
1676	int			error;
1677
1678	/*
1679	 * Then read in the AGI buffer and recheck with the AGI buffer
1680	 * lock held.
1681	 */
1682	error = xfs_ialloc_read_agi(pag, *tpp, &agbp);
1683	if (error)
1684		return error;
1685
1686	if (!pag->pagi_freecount) {
1687		if (!ok_alloc) {
1688			error = -EAGAIN;
1689			goto out_release;
1690		}
1691
1692		error = xfs_ialloc_ag_alloc(*tpp, agbp, pag);
1693		if (error < 0)
1694			goto out_release;
1695
1696		/*
1697		 * We successfully allocated space for an inode cluster in this
1698		 * AG.  Roll the transaction so that we can allocate one of the
1699		 * new inodes.
1700		 */
1701		ASSERT(pag->pagi_freecount > 0);
1702		error = xfs_dialloc_roll(tpp, agbp);
1703		if (error)
1704			goto out_release;
1705	}
1706
1707	/* Allocate an inode in the found AG */
1708	error = xfs_dialloc_ag(*tpp, agbp, pag, parent, &ino);
1709	if (!error)
1710		*new_ino = ino;
1711	return error;
1712
1713out_release:
1714	xfs_trans_brelse(*tpp, agbp);
1715	return error;
1716}
1717
1718/*
1719 * Allocate an on-disk inode.
1720 *
1721 * Mode is used to tell whether the new inode is a directory and hence where to
1722 * locate it. The on-disk inode that is allocated will be returned in @new_ino
1723 * on success, otherwise an error will be set to indicate the failure (e.g.
1724 * -ENOSPC).
1725 */
1726int
1727xfs_dialloc(
1728	struct xfs_trans	**tpp,
1729	xfs_ino_t		parent,
1730	umode_t			mode,
1731	xfs_ino_t		*new_ino)
1732{
1733	struct xfs_mount	*mp = (*tpp)->t_mountp;
1734	xfs_agnumber_t		agno;
1735	int			error = 0;
1736	xfs_agnumber_t		start_agno;
1737	struct xfs_perag	*pag;
1738	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
1739	bool			ok_alloc = true;
 
1740	int			flags;
1741	xfs_ino_t		ino;
1742
1743	/*
1744	 * Directories, symlinks, and regular files frequently allocate at least
1745	 * one block, so factor that potential expansion when we examine whether
1746	 * an AG has enough space for file creation.
1747	 */
1748	if (S_ISDIR(mode))
1749		start_agno = xfs_ialloc_next_ag(mp);
 
1750	else {
1751		start_agno = XFS_INO_TO_AGNO(mp, parent);
1752		if (start_agno >= mp->m_maxagi)
1753			start_agno = 0;
1754	}
1755
1756	/*
1757	 * If we have already hit the ceiling of inode blocks then clear
1758	 * ok_alloc so we scan all available agi structures for a free
1759	 * inode.
1760	 *
1761	 * Read rough value of mp->m_icount by percpu_counter_read_positive,
1762	 * which will sacrifice the preciseness but improve the performance.
1763	 */
1764	if (igeo->maxicount &&
1765	    percpu_counter_read_positive(&mp->m_icount) + igeo->ialloc_inos
1766							> igeo->maxicount) {
1767		ok_alloc = false;
1768	}
1769
1770	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1771	 * Loop until we find an allocation group that either has free inodes
1772	 * or in which we can allocate some inodes.  Iterate through the
1773	 * allocation groups upward, wrapping at the end.
1774	 */
1775	agno = start_agno;
1776	flags = XFS_ALLOC_FLAG_TRYLOCK;
1777	for (;;) {
1778		pag = xfs_perag_get(mp, agno);
1779		if (xfs_dialloc_good_ag(*tpp, pag, mode, flags, ok_alloc)) {
1780			error = xfs_dialloc_try_ag(tpp, pag, parent,
1781					&ino, ok_alloc);
1782			if (error != -EAGAIN)
1783				break;
 
1784		}
1785
1786		if (xfs_is_shutdown(mp)) {
1787			error = -EFSCORRUPTED;
1788			break;
1789		}
1790		if (++agno == mp->m_maxagi)
1791			agno = 0;
1792		if (agno == start_agno) {
1793			if (!flags) {
1794				error = -ENOSPC;
1795				break;
1796			}
1797			flags = 0;
 
 
 
1798		}
1799		xfs_perag_put(pag);
1800	}
1801
1802	if (!error)
1803		*new_ino = ino;
1804	xfs_perag_put(pag);
1805	return error;
1806}
1807
1808/*
1809 * Free the blocks of an inode chunk. We must consider that the inode chunk
1810 * might be sparse and only free the regions that are allocated as part of the
1811 * chunk.
1812 */
1813STATIC void
1814xfs_difree_inode_chunk(
1815	struct xfs_trans		*tp,
1816	xfs_agnumber_t			agno,
1817	struct xfs_inobt_rec_incore	*rec)
1818{
1819	struct xfs_mount		*mp = tp->t_mountp;
1820	xfs_agblock_t			sagbno = XFS_AGINO_TO_AGBNO(mp,
1821							rec->ir_startino);
1822	int				startidx, endidx;
1823	int				nextbit;
1824	xfs_agblock_t			agbno;
1825	int				contigblk;
1826	DECLARE_BITMAP(holemask, XFS_INOBT_HOLEMASK_BITS);
1827
1828	if (!xfs_inobt_issparse(rec->ir_holemask)) {
1829		/* not sparse, calculate extent info directly */
1830		xfs_free_extent_later(tp, XFS_AGB_TO_FSB(mp, agno, sagbno),
1831				  M_IGEO(mp)->ialloc_blks,
1832				  &XFS_RMAP_OINFO_INODES);
1833		return;
1834	}
1835
1836	/* holemask is only 16-bits (fits in an unsigned long) */
1837	ASSERT(sizeof(rec->ir_holemask) <= sizeof(holemask[0]));
1838	holemask[0] = rec->ir_holemask;
1839
1840	/*
1841	 * Find contiguous ranges of zeroes (i.e., allocated regions) in the
1842	 * holemask and convert the start/end index of each range to an extent.
1843	 * We start with the start and end index both pointing at the first 0 in
1844	 * the mask.
1845	 */
1846	startidx = endidx = find_first_zero_bit(holemask,
1847						XFS_INOBT_HOLEMASK_BITS);
1848	nextbit = startidx + 1;
1849	while (startidx < XFS_INOBT_HOLEMASK_BITS) {
 
 
1850		nextbit = find_next_zero_bit(holemask, XFS_INOBT_HOLEMASK_BITS,
1851					     nextbit);
1852		/*
1853		 * If the next zero bit is contiguous, update the end index of
1854		 * the current range and continue.
1855		 */
1856		if (nextbit != XFS_INOBT_HOLEMASK_BITS &&
1857		    nextbit == endidx + 1) {
1858			endidx = nextbit;
1859			goto next;
1860		}
1861
1862		/*
1863		 * nextbit is not contiguous with the current end index. Convert
1864		 * the current start/end to an extent and add it to the free
1865		 * list.
1866		 */
1867		agbno = sagbno + (startidx * XFS_INODES_PER_HOLEMASK_BIT) /
1868				  mp->m_sb.sb_inopblock;
1869		contigblk = ((endidx - startidx + 1) *
1870			     XFS_INODES_PER_HOLEMASK_BIT) /
1871			    mp->m_sb.sb_inopblock;
1872
1873		ASSERT(agbno % mp->m_sb.sb_spino_align == 0);
1874		ASSERT(contigblk % mp->m_sb.sb_spino_align == 0);
1875		xfs_free_extent_later(tp, XFS_AGB_TO_FSB(mp, agno, agbno),
1876				  contigblk, &XFS_RMAP_OINFO_INODES);
 
 
 
 
1877
1878		/* reset range to current bit and carry on... */
1879		startidx = endidx = nextbit;
1880
1881next:
1882		nextbit++;
1883	}
 
1884}
1885
1886STATIC int
1887xfs_difree_inobt(
1888	struct xfs_mount		*mp,
1889	struct xfs_trans		*tp,
1890	struct xfs_buf			*agbp,
1891	struct xfs_perag		*pag,
1892	xfs_agino_t			agino,
1893	struct xfs_icluster		*xic,
1894	struct xfs_inobt_rec_incore	*orec)
1895{
 
1896	struct xfs_agi			*agi = agbp->b_addr;
1897	struct xfs_btree_cur		*cur;
1898	struct xfs_inobt_rec_incore	rec;
1899	int				ilen;
1900	int				error;
1901	int				i;
1902	int				off;
1903
1904	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
1905	ASSERT(XFS_AGINO_TO_AGBNO(mp, agino) < be32_to_cpu(agi->agi_length));
1906
1907	/*
1908	 * Initialize the cursor.
1909	 */
1910	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_INO);
1911
1912	error = xfs_check_agi_freecount(cur);
1913	if (error)
1914		goto error0;
1915
1916	/*
1917	 * Look for the entry describing this inode.
1918	 */
1919	if ((error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i))) {
1920		xfs_warn(mp, "%s: xfs_inobt_lookup() returned error %d.",
1921			__func__, error);
1922		goto error0;
1923	}
1924	if (XFS_IS_CORRUPT(mp, i != 1)) {
 
1925		error = -EFSCORRUPTED;
1926		goto error0;
1927	}
1928	error = xfs_inobt_get_rec(cur, &rec, &i);
1929	if (error) {
1930		xfs_warn(mp, "%s: xfs_inobt_get_rec() returned error %d.",
1931			__func__, error);
1932		goto error0;
1933	}
1934	if (XFS_IS_CORRUPT(mp, i != 1)) {
 
1935		error = -EFSCORRUPTED;
1936		goto error0;
1937	}
1938	/*
1939	 * Get the offset in the inode chunk.
1940	 */
1941	off = agino - rec.ir_startino;
1942	ASSERT(off >= 0 && off < XFS_INODES_PER_CHUNK);
1943	ASSERT(!(rec.ir_free & XFS_INOBT_MASK(off)));
1944	/*
1945	 * Mark the inode free & increment the count.
1946	 */
1947	rec.ir_free |= XFS_INOBT_MASK(off);
1948	rec.ir_freecount++;
1949
1950	/*
1951	 * When an inode chunk is free, it becomes eligible for removal. Don't
1952	 * remove the chunk if the block size is large enough for multiple inode
1953	 * chunks (that might not be free).
1954	 */
1955	if (!xfs_has_ikeep(mp) && rec.ir_free == XFS_INOBT_ALL_FREE &&
1956	    mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK) {
1957		struct xfs_perag	*pag = agbp->b_pag;
1958
1959		xic->deleted = true;
1960		xic->first_ino = XFS_AGINO_TO_INO(mp, pag->pag_agno,
1961				rec.ir_startino);
1962		xic->alloc = xfs_inobt_irec_to_allocmask(&rec);
1963
1964		/*
1965		 * Remove the inode cluster from the AGI B+Tree, adjust the
1966		 * AGI and Superblock inode counts, and mark the disk space
1967		 * to be freed when the transaction is committed.
1968		 */
1969		ilen = rec.ir_freecount;
1970		be32_add_cpu(&agi->agi_count, -ilen);
1971		be32_add_cpu(&agi->agi_freecount, -(ilen - 1));
1972		xfs_ialloc_log_agi(tp, agbp, XFS_AGI_COUNT | XFS_AGI_FREECOUNT);
1973		pag->pagi_freecount -= ilen - 1;
1974		pag->pagi_count -= ilen;
1975		xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, -ilen);
1976		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -(ilen - 1));
1977
1978		if ((error = xfs_btree_delete(cur, &i))) {
1979			xfs_warn(mp, "%s: xfs_btree_delete returned error %d.",
1980				__func__, error);
1981			goto error0;
1982		}
1983
1984		xfs_difree_inode_chunk(tp, pag->pag_agno, &rec);
 
 
1985	} else {
1986		xic->deleted = false;
1987
1988		error = xfs_inobt_update(cur, &rec);
1989		if (error) {
1990			xfs_warn(mp, "%s: xfs_inobt_update returned error %d.",
1991				__func__, error);
1992			goto error0;
1993		}
1994
1995		/*
1996		 * Change the inode free counts and log the ag/sb changes.
1997		 */
1998		be32_add_cpu(&agi->agi_freecount, 1);
1999		xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
2000		pag->pagi_freecount++;
2001		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, 1);
2002	}
2003
2004	error = xfs_check_agi_freecount(cur);
2005	if (error)
2006		goto error0;
2007
2008	*orec = rec;
2009	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2010	return 0;
2011
2012error0:
2013	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2014	return error;
2015}
2016
2017/*
2018 * Free an inode in the free inode btree.
2019 */
2020STATIC int
2021xfs_difree_finobt(
2022	struct xfs_mount		*mp,
2023	struct xfs_trans		*tp,
2024	struct xfs_buf			*agbp,
2025	struct xfs_perag		*pag,
2026	xfs_agino_t			agino,
2027	struct xfs_inobt_rec_incore	*ibtrec) /* inobt record */
2028{
 
2029	struct xfs_btree_cur		*cur;
2030	struct xfs_inobt_rec_incore	rec;
2031	int				offset = agino - ibtrec->ir_startino;
2032	int				error;
2033	int				i;
2034
2035	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_FINO);
2036
2037	error = xfs_inobt_lookup(cur, ibtrec->ir_startino, XFS_LOOKUP_EQ, &i);
2038	if (error)
2039		goto error;
2040	if (i == 0) {
2041		/*
2042		 * If the record does not exist in the finobt, we must have just
2043		 * freed an inode in a previously fully allocated chunk. If not,
2044		 * something is out of sync.
2045		 */
2046		if (XFS_IS_CORRUPT(mp, ibtrec->ir_freecount != 1)) {
 
2047			error = -EFSCORRUPTED;
2048			goto error;
2049		}
2050
2051		error = xfs_inobt_insert_rec(cur, ibtrec->ir_holemask,
2052					     ibtrec->ir_count,
2053					     ibtrec->ir_freecount,
2054					     ibtrec->ir_free, &i);
2055		if (error)
2056			goto error;
2057		ASSERT(i == 1);
2058
2059		goto out;
2060	}
2061
2062	/*
2063	 * Read and update the existing record. We could just copy the ibtrec
2064	 * across here, but that would defeat the purpose of having redundant
2065	 * metadata. By making the modifications independently, we can catch
2066	 * corruptions that we wouldn't see if we just copied from one record
2067	 * to another.
2068	 */
2069	error = xfs_inobt_get_rec(cur, &rec, &i);
2070	if (error)
2071		goto error;
2072	if (XFS_IS_CORRUPT(mp, i != 1)) {
 
2073		error = -EFSCORRUPTED;
2074		goto error;
2075	}
2076
2077	rec.ir_free |= XFS_INOBT_MASK(offset);
2078	rec.ir_freecount++;
2079
2080	if (XFS_IS_CORRUPT(mp,
2081			   rec.ir_free != ibtrec->ir_free ||
2082			   rec.ir_freecount != ibtrec->ir_freecount)) {
 
2083		error = -EFSCORRUPTED;
2084		goto error;
2085	}
2086
2087	/*
2088	 * The content of inobt records should always match between the inobt
2089	 * and finobt. The lifecycle of records in the finobt is different from
2090	 * the inobt in that the finobt only tracks records with at least one
2091	 * free inode. Hence, if all of the inodes are free and we aren't
2092	 * keeping inode chunks permanently on disk, remove the record.
2093	 * Otherwise, update the record with the new information.
2094	 *
2095	 * Note that we currently can't free chunks when the block size is large
2096	 * enough for multiple chunks. Leave the finobt record to remain in sync
2097	 * with the inobt.
2098	 */
2099	if (!xfs_has_ikeep(mp) && rec.ir_free == XFS_INOBT_ALL_FREE &&
2100	    mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK) {
2101		error = xfs_btree_delete(cur, &i);
2102		if (error)
2103			goto error;
2104		ASSERT(i == 1);
2105	} else {
2106		error = xfs_inobt_update(cur, &rec);
2107		if (error)
2108			goto error;
2109	}
2110
2111out:
2112	error = xfs_check_agi_freecount(cur);
2113	if (error)
2114		goto error;
2115
2116	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2117	return 0;
2118
2119error:
2120	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2121	return error;
2122}
2123
2124/*
2125 * Free disk inode.  Carefully avoids touching the incore inode, all
2126 * manipulations incore are the caller's responsibility.
2127 * The on-disk inode is not changed by this operation, only the
2128 * btree (free inode mask) is changed.
2129 */
2130int
2131xfs_difree(
2132	struct xfs_trans	*tp,
2133	struct xfs_perag	*pag,
2134	xfs_ino_t		inode,
2135	struct xfs_icluster	*xic)
2136{
2137	/* REFERENCED */
2138	xfs_agblock_t		agbno;	/* block number containing inode */
2139	struct xfs_buf		*agbp;	/* buffer for allocation group header */
2140	xfs_agino_t		agino;	/* allocation group inode number */
2141	int			error;	/* error return value */
2142	struct xfs_mount	*mp = tp->t_mountp;
2143	struct xfs_inobt_rec_incore rec;/* btree record */
2144
2145	/*
2146	 * Break up inode number into its components.
2147	 */
2148	if (pag->pag_agno != XFS_INO_TO_AGNO(mp, inode)) {
2149		xfs_warn(mp, "%s: agno != pag->pag_agno (%d != %d).",
2150			__func__, XFS_INO_TO_AGNO(mp, inode), pag->pag_agno);
2151		ASSERT(0);
2152		return -EINVAL;
2153	}
2154	agino = XFS_INO_TO_AGINO(mp, inode);
2155	if (inode != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino))  {
2156		xfs_warn(mp, "%s: inode != XFS_AGINO_TO_INO() (%llu != %llu).",
2157			__func__, (unsigned long long)inode,
2158			(unsigned long long)XFS_AGINO_TO_INO(mp, pag->pag_agno, agino));
2159		ASSERT(0);
2160		return -EINVAL;
2161	}
2162	agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2163	if (agbno >= mp->m_sb.sb_agblocks)  {
2164		xfs_warn(mp, "%s: agbno >= mp->m_sb.sb_agblocks (%d >= %d).",
2165			__func__, agbno, mp->m_sb.sb_agblocks);
2166		ASSERT(0);
2167		return -EINVAL;
2168	}
2169	/*
2170	 * Get the allocation group header.
2171	 */
2172	error = xfs_ialloc_read_agi(pag, tp, &agbp);
2173	if (error) {
2174		xfs_warn(mp, "%s: xfs_ialloc_read_agi() returned error %d.",
2175			__func__, error);
2176		return error;
2177	}
2178
2179	/*
2180	 * Fix up the inode allocation btree.
2181	 */
2182	error = xfs_difree_inobt(mp, tp, agbp, pag, agino, xic, &rec);
2183	if (error)
2184		goto error0;
2185
2186	/*
2187	 * Fix up the free inode btree.
2188	 */
2189	if (xfs_has_finobt(mp)) {
2190		error = xfs_difree_finobt(mp, tp, agbp, pag, agino, &rec);
2191		if (error)
2192			goto error0;
2193	}
2194
2195	return 0;
2196
2197error0:
2198	return error;
2199}
2200
2201STATIC int
2202xfs_imap_lookup(
2203	struct xfs_mount	*mp,
2204	struct xfs_trans	*tp,
2205	struct xfs_perag	*pag,
 
2206	xfs_agino_t		agino,
2207	xfs_agblock_t		agbno,
2208	xfs_agblock_t		*chunk_agbno,
2209	xfs_agblock_t		*offset_agbno,
2210	int			flags)
2211{
 
2212	struct xfs_inobt_rec_incore rec;
2213	struct xfs_btree_cur	*cur;
2214	struct xfs_buf		*agbp;
2215	int			error;
2216	int			i;
2217
2218	error = xfs_ialloc_read_agi(pag, tp, &agbp);
2219	if (error) {
2220		xfs_alert(mp,
2221			"%s: xfs_ialloc_read_agi() returned error %d, agno %d",
2222			__func__, error, pag->pag_agno);
2223		return error;
2224	}
2225
2226	/*
2227	 * Lookup the inode record for the given agino. If the record cannot be
2228	 * found, then it's an invalid inode number and we should abort. Once
2229	 * we have a record, we need to ensure it contains the inode number
2230	 * we are looking up.
2231	 */
2232	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_INO);
2233	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i);
2234	if (!error) {
2235		if (i)
2236			error = xfs_inobt_get_rec(cur, &rec, &i);
2237		if (!error && i == 0)
2238			error = -EINVAL;
2239	}
2240
2241	xfs_trans_brelse(tp, agbp);
2242	xfs_btree_del_cursor(cur, error);
2243	if (error)
2244		return error;
2245
2246	/* check that the returned record contains the required inode */
2247	if (rec.ir_startino > agino ||
2248	    rec.ir_startino + M_IGEO(mp)->ialloc_inos <= agino)
2249		return -EINVAL;
2250
2251	/* for untrusted inodes check it is allocated first */
2252	if ((flags & XFS_IGET_UNTRUSTED) &&
2253	    (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino)))
2254		return -EINVAL;
2255
2256	*chunk_agbno = XFS_AGINO_TO_AGBNO(mp, rec.ir_startino);
2257	*offset_agbno = agbno - *chunk_agbno;
2258	return 0;
2259}
2260
2261/*
2262 * Return the location of the inode in imap, for mapping it into a buffer.
2263 */
2264int
2265xfs_imap(
2266	struct xfs_mount	 *mp,	/* file system mount structure */
2267	struct xfs_trans	 *tp,	/* transaction pointer */
2268	xfs_ino_t		ino,	/* inode to locate */
2269	struct xfs_imap		*imap,	/* location map structure */
2270	uint			flags)	/* flags for inode btree lookup */
2271{
 
2272	xfs_agblock_t		agbno;	/* block number of inode in the alloc group */
2273	xfs_agino_t		agino;	/* inode number within alloc group */
2274	xfs_agblock_t		chunk_agbno;	/* first block in inode chunk */
2275	xfs_agblock_t		cluster_agbno;	/* first block in inode cluster */
2276	int			error;	/* error code */
2277	int			offset;	/* index of inode in its buffer */
2278	xfs_agblock_t		offset_agbno;	/* blks from chunk start to inode */
2279	struct xfs_perag	*pag;
2280
2281	ASSERT(ino != NULLFSINO);
2282
2283	/*
2284	 * Split up the inode number into its parts.
2285	 */
2286	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ino));
2287	agino = XFS_INO_TO_AGINO(mp, ino);
2288	agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2289	if (!pag || agbno >= mp->m_sb.sb_agblocks ||
2290	    ino != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino)) {
2291		error = -EINVAL;
2292#ifdef DEBUG
2293		/*
2294		 * Don't output diagnostic information for untrusted inodes
2295		 * as they can be invalid without implying corruption.
2296		 */
2297		if (flags & XFS_IGET_UNTRUSTED)
2298			goto out_drop;
2299		if (!pag) {
2300			xfs_alert(mp,
2301				"%s: agno (%d) >= mp->m_sb.sb_agcount (%d)",
2302				__func__, XFS_INO_TO_AGNO(mp, ino),
2303				mp->m_sb.sb_agcount);
2304		}
2305		if (agbno >= mp->m_sb.sb_agblocks) {
2306			xfs_alert(mp,
2307		"%s: agbno (0x%llx) >= mp->m_sb.sb_agblocks (0x%lx)",
2308				__func__, (unsigned long long)agbno,
2309				(unsigned long)mp->m_sb.sb_agblocks);
2310		}
2311		if (pag && ino != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino)) {
2312			xfs_alert(mp,
2313		"%s: ino (0x%llx) != XFS_AGINO_TO_INO() (0x%llx)",
2314				__func__, ino,
2315				XFS_AGINO_TO_INO(mp, pag->pag_agno, agino));
2316		}
2317		xfs_stack_trace();
2318#endif /* DEBUG */
2319		goto out_drop;
2320	}
2321
2322	/*
2323	 * For bulkstat and handle lookups, we have an untrusted inode number
2324	 * that we have to verify is valid. We cannot do this just by reading
2325	 * the inode buffer as it may have been unlinked and removed leaving
2326	 * inodes in stale state on disk. Hence we have to do a btree lookup
2327	 * in all cases where an untrusted inode number is passed.
2328	 */
2329	if (flags & XFS_IGET_UNTRUSTED) {
2330		error = xfs_imap_lookup(mp, tp, pag, agino, agbno,
2331					&chunk_agbno, &offset_agbno, flags);
2332		if (error)
2333			goto out_drop;
2334		goto out_map;
2335	}
2336
2337	/*
2338	 * If the inode cluster size is the same as the blocksize or
2339	 * smaller we get to the buffer by simple arithmetics.
2340	 */
2341	if (M_IGEO(mp)->blocks_per_cluster == 1) {
2342		offset = XFS_INO_TO_OFFSET(mp, ino);
2343		ASSERT(offset < mp->m_sb.sb_inopblock);
2344
2345		imap->im_blkno = XFS_AGB_TO_DADDR(mp, pag->pag_agno, agbno);
2346		imap->im_len = XFS_FSB_TO_BB(mp, 1);
2347		imap->im_boffset = (unsigned short)(offset <<
2348							mp->m_sb.sb_inodelog);
2349		error = 0;
2350		goto out_drop;
2351	}
2352
2353	/*
2354	 * If the inode chunks are aligned then use simple maths to
2355	 * find the location. Otherwise we have to do a btree
2356	 * lookup to find the location.
2357	 */
2358	if (M_IGEO(mp)->inoalign_mask) {
2359		offset_agbno = agbno & M_IGEO(mp)->inoalign_mask;
2360		chunk_agbno = agbno - offset_agbno;
2361	} else {
2362		error = xfs_imap_lookup(mp, tp, pag, agino, agbno,
2363					&chunk_agbno, &offset_agbno, flags);
2364		if (error)
2365			goto out_drop;
2366	}
2367
2368out_map:
2369	ASSERT(agbno >= chunk_agbno);
2370	cluster_agbno = chunk_agbno +
2371		((offset_agbno / M_IGEO(mp)->blocks_per_cluster) *
2372		 M_IGEO(mp)->blocks_per_cluster);
2373	offset = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) +
2374		XFS_INO_TO_OFFSET(mp, ino);
2375
2376	imap->im_blkno = XFS_AGB_TO_DADDR(mp, pag->pag_agno, cluster_agbno);
2377	imap->im_len = XFS_FSB_TO_BB(mp, M_IGEO(mp)->blocks_per_cluster);
2378	imap->im_boffset = (unsigned short)(offset << mp->m_sb.sb_inodelog);
2379
2380	/*
2381	 * If the inode number maps to a block outside the bounds
2382	 * of the file system then return NULL rather than calling
2383	 * read_buf and panicing when we get an error from the
2384	 * driver.
2385	 */
2386	if ((imap->im_blkno + imap->im_len) >
2387	    XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
2388		xfs_alert(mp,
2389	"%s: (im_blkno (0x%llx) + im_len (0x%llx)) > sb_dblocks (0x%llx)",
2390			__func__, (unsigned long long) imap->im_blkno,
2391			(unsigned long long) imap->im_len,
2392			XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
2393		error = -EINVAL;
2394		goto out_drop;
2395	}
2396	error = 0;
2397out_drop:
2398	if (pag)
2399		xfs_perag_put(pag);
2400	return error;
2401}
2402
2403/*
2404 * Log specified fields for the ag hdr (inode section). The growth of the agi
2405 * structure over time requires that we interpret the buffer as two logical
2406 * regions delineated by the end of the unlinked list. This is due to the size
2407 * of the hash table and its location in the middle of the agi.
2408 *
2409 * For example, a request to log a field before agi_unlinked and a field after
2410 * agi_unlinked could cause us to log the entire hash table and use an excessive
2411 * amount of log space. To avoid this behavior, log the region up through
2412 * agi_unlinked in one call and the region after agi_unlinked through the end of
2413 * the structure in another.
2414 */
2415void
2416xfs_ialloc_log_agi(
2417	struct xfs_trans	*tp,
2418	struct xfs_buf		*bp,
2419	uint32_t		fields)
2420{
2421	int			first;		/* first byte number */
2422	int			last;		/* last byte number */
2423	static const short	offsets[] = {	/* field starting offsets */
2424					/* keep in sync with bit definitions */
2425		offsetof(xfs_agi_t, agi_magicnum),
2426		offsetof(xfs_agi_t, agi_versionnum),
2427		offsetof(xfs_agi_t, agi_seqno),
2428		offsetof(xfs_agi_t, agi_length),
2429		offsetof(xfs_agi_t, agi_count),
2430		offsetof(xfs_agi_t, agi_root),
2431		offsetof(xfs_agi_t, agi_level),
2432		offsetof(xfs_agi_t, agi_freecount),
2433		offsetof(xfs_agi_t, agi_newino),
2434		offsetof(xfs_agi_t, agi_dirino),
2435		offsetof(xfs_agi_t, agi_unlinked),
2436		offsetof(xfs_agi_t, agi_free_root),
2437		offsetof(xfs_agi_t, agi_free_level),
2438		offsetof(xfs_agi_t, agi_iblocks),
2439		sizeof(xfs_agi_t)
2440	};
2441#ifdef DEBUG
2442	struct xfs_agi		*agi = bp->b_addr;
2443
2444	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
2445#endif
2446
2447	/*
2448	 * Compute byte offsets for the first and last fields in the first
2449	 * region and log the agi buffer. This only logs up through
2450	 * agi_unlinked.
2451	 */
2452	if (fields & XFS_AGI_ALL_BITS_R1) {
2453		xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R1,
2454				  &first, &last);
2455		xfs_trans_log_buf(tp, bp, first, last);
2456	}
2457
2458	/*
2459	 * Mask off the bits in the first region and calculate the first and
2460	 * last field offsets for any bits in the second region.
2461	 */
2462	fields &= ~XFS_AGI_ALL_BITS_R1;
2463	if (fields) {
2464		xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R2,
2465				  &first, &last);
2466		xfs_trans_log_buf(tp, bp, first, last);
2467	}
2468}
2469
2470static xfs_failaddr_t
2471xfs_agi_verify(
2472	struct xfs_buf	*bp)
2473{
2474	struct xfs_mount *mp = bp->b_mount;
2475	struct xfs_agi	*agi = bp->b_addr;
2476	int		i;
 
 
 
2477
2478	if (xfs_has_crc(mp)) {
2479		if (!uuid_equal(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid))
2480			return __this_address;
2481		if (!xfs_log_check_lsn(mp, be64_to_cpu(agi->agi_lsn)))
2482			return __this_address;
2483	}
2484
2485	/*
2486	 * Validate the magic number of the agi block.
2487	 */
2488	if (!xfs_verify_magic(bp, agi->agi_magicnum))
2489		return __this_address;
2490	if (!XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)))
2491		return __this_address;
2492
 
 
 
 
2493	if (be32_to_cpu(agi->agi_level) < 1 ||
2494	    be32_to_cpu(agi->agi_level) > M_IGEO(mp)->inobt_maxlevels)
2495		return __this_address;
2496
2497	if (xfs_has_finobt(mp) &&
2498	    (be32_to_cpu(agi->agi_free_level) < 1 ||
2499	     be32_to_cpu(agi->agi_free_level) > M_IGEO(mp)->inobt_maxlevels))
2500		return __this_address;
2501
2502	/*
2503	 * during growfs operations, the perag is not fully initialised,
2504	 * so we can't use it for any useful checking. growfs ensures we can't
2505	 * use it by using uncached buffers that don't have the perag attached
2506	 * so we can detect and avoid this problem.
2507	 */
2508	if (bp->b_pag && be32_to_cpu(agi->agi_seqno) != bp->b_pag->pag_agno)
2509		return __this_address;
2510
2511	for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++) {
2512		if (agi->agi_unlinked[i] == cpu_to_be32(NULLAGINO))
2513			continue;
2514		if (!xfs_verify_ino(mp, be32_to_cpu(agi->agi_unlinked[i])))
2515			return __this_address;
2516	}
2517
2518	return NULL;
2519}
2520
2521static void
2522xfs_agi_read_verify(
2523	struct xfs_buf	*bp)
2524{
2525	struct xfs_mount *mp = bp->b_mount;
2526	xfs_failaddr_t	fa;
2527
2528	if (xfs_has_crc(mp) &&
2529	    !xfs_buf_verify_cksum(bp, XFS_AGI_CRC_OFF))
2530		xfs_verifier_error(bp, -EFSBADCRC, __this_address);
2531	else {
2532		fa = xfs_agi_verify(bp);
2533		if (XFS_TEST_ERROR(fa, mp, XFS_ERRTAG_IALLOC_READ_AGI))
2534			xfs_verifier_error(bp, -EFSCORRUPTED, fa);
2535	}
2536}
2537
2538static void
2539xfs_agi_write_verify(
2540	struct xfs_buf	*bp)
2541{
2542	struct xfs_mount	*mp = bp->b_mount;
2543	struct xfs_buf_log_item	*bip = bp->b_log_item;
2544	struct xfs_agi		*agi = bp->b_addr;
2545	xfs_failaddr_t		fa;
2546
2547	fa = xfs_agi_verify(bp);
2548	if (fa) {
2549		xfs_verifier_error(bp, -EFSCORRUPTED, fa);
2550		return;
2551	}
2552
2553	if (!xfs_has_crc(mp))
2554		return;
2555
2556	if (bip)
2557		agi->agi_lsn = cpu_to_be64(bip->bli_item.li_lsn);
2558	xfs_buf_update_cksum(bp, XFS_AGI_CRC_OFF);
2559}
2560
2561const struct xfs_buf_ops xfs_agi_buf_ops = {
2562	.name = "xfs_agi",
2563	.magic = { cpu_to_be32(XFS_AGI_MAGIC), cpu_to_be32(XFS_AGI_MAGIC) },
2564	.verify_read = xfs_agi_read_verify,
2565	.verify_write = xfs_agi_write_verify,
2566	.verify_struct = xfs_agi_verify,
2567};
2568
2569/*
2570 * Read in the allocation group header (inode allocation section)
2571 */
2572int
2573xfs_read_agi(
2574	struct xfs_perag	*pag,
2575	struct xfs_trans	*tp,
2576	struct xfs_buf		**agibpp)
2577{
2578	struct xfs_mount	*mp = pag->pag_mount;
2579	int			error;
2580
2581	trace_xfs_read_agi(pag->pag_mount, pag->pag_agno);
2582
2583	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
2584			XFS_AG_DADDR(mp, pag->pag_agno, XFS_AGI_DADDR(mp)),
2585			XFS_FSS_TO_BB(mp, 1), 0, agibpp, &xfs_agi_buf_ops);
 
 
2586	if (error)
2587		return error;
2588	if (tp)
2589		xfs_trans_buf_set_type(tp, *agibpp, XFS_BLFT_AGI_BUF);
2590
2591	xfs_buf_set_ref(*agibpp, XFS_AGI_REF);
2592	return 0;
2593}
2594
2595/*
2596 * Read in the agi and initialise the per-ag data. If the caller supplies a
2597 * @agibpp, return the locked AGI buffer to them, otherwise release it.
2598 */
2599int
2600xfs_ialloc_read_agi(
2601	struct xfs_perag	*pag,
2602	struct xfs_trans	*tp,
2603	struct xfs_buf		**agibpp)
2604{
2605	struct xfs_buf		*agibp;
2606	struct xfs_agi		*agi;
2607	int			error;
2608
2609	trace_xfs_ialloc_read_agi(pag->pag_mount, pag->pag_agno);
2610
2611	error = xfs_read_agi(pag, tp, &agibp);
2612	if (error)
2613		return error;
2614
2615	agi = agibp->b_addr;
2616	if (!pag->pagi_init) {
2617		pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);
2618		pag->pagi_count = be32_to_cpu(agi->agi_count);
2619		pag->pagi_init = 1;
2620	}
2621
2622	/*
2623	 * It's possible for these to be out of sync if
2624	 * we are in the middle of a forced shutdown.
2625	 */
2626	ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
2627		xfs_is_shutdown(pag->pag_mount));
2628	if (agibpp)
2629		*agibpp = agibp;
2630	else
2631		xfs_trans_brelse(tp, agibp);
2632	return 0;
2633}
2634
2635/* Is there an inode record covering a given range of inode numbers? */
2636int
2637xfs_ialloc_has_inode_record(
2638	struct xfs_btree_cur	*cur,
2639	xfs_agino_t		low,
2640	xfs_agino_t		high,
2641	bool			*exists)
2642{
2643	struct xfs_inobt_rec_incore	irec;
2644	xfs_agino_t		agino;
2645	uint16_t		holemask;
2646	int			has_record;
2647	int			i;
2648	int			error;
2649
2650	*exists = false;
2651	error = xfs_inobt_lookup(cur, low, XFS_LOOKUP_LE, &has_record);
2652	while (error == 0 && has_record) {
 
 
 
 
 
2653		error = xfs_inobt_get_rec(cur, &irec, &has_record);
2654		if (error || irec.ir_startino > high)
 
 
2655			break;
2656
2657		agino = irec.ir_startino;
2658		holemask = irec.ir_holemask;
2659		for (i = 0; i < XFS_INOBT_HOLEMASK_BITS; holemask >>= 1,
2660				i++, agino += XFS_INODES_PER_HOLEMASK_BIT) {
2661			if (holemask & 1)
2662				continue;
2663			if (agino + XFS_INODES_PER_HOLEMASK_BIT > low &&
2664					agino <= high) {
2665				*exists = true;
2666				return 0;
2667			}
 
2668		}
2669
2670		error = xfs_btree_increment(cur, 0, &has_record);
 
 
2671	}
2672	return error;
 
 
2673}
2674
2675/* Is there an inode record covering a given extent? */
2676int
2677xfs_ialloc_has_inodes_at_extent(
2678	struct xfs_btree_cur	*cur,
2679	xfs_agblock_t		bno,
2680	xfs_extlen_t		len,
2681	bool			*exists)
2682{
2683	xfs_agino_t		low;
2684	xfs_agino_t		high;
 
 
 
 
 
2685
2686	low = XFS_AGB_TO_AGINO(cur->bc_mp, bno);
2687	high = XFS_AGB_TO_AGINO(cur->bc_mp, bno + len) - 1;
 
2688
2689	return xfs_ialloc_has_inode_record(cur, low, high, exists);
 
 
 
 
 
 
2690}
2691
2692struct xfs_ialloc_count_inodes {
2693	xfs_agino_t			count;
2694	xfs_agino_t			freecount;
2695};
2696
2697/* Record inode counts across all inobt records. */
2698STATIC int
2699xfs_ialloc_count_inodes_rec(
2700	struct xfs_btree_cur		*cur,
2701	const union xfs_btree_rec	*rec,
2702	void				*priv)
2703{
2704	struct xfs_inobt_rec_incore	irec;
2705	struct xfs_ialloc_count_inodes	*ci = priv;
 
2706
2707	xfs_inobt_btrec_to_irec(cur->bc_mp, rec, &irec);
 
 
 
 
2708	ci->count += irec.ir_count;
2709	ci->freecount += irec.ir_freecount;
2710
2711	return 0;
2712}
2713
2714/* Count allocated and free inodes under an inobt. */
2715int
2716xfs_ialloc_count_inodes(
2717	struct xfs_btree_cur		*cur,
2718	xfs_agino_t			*count,
2719	xfs_agino_t			*freecount)
2720{
2721	struct xfs_ialloc_count_inodes	ci = {0};
2722	int				error;
2723
2724	ASSERT(cur->bc_btnum == XFS_BTNUM_INO);
2725	error = xfs_btree_query_all(cur, xfs_ialloc_count_inodes_rec, &ci);
2726	if (error)
2727		return error;
2728
2729	*count = ci.count;
2730	*freecount = ci.freecount;
2731	return 0;
2732}
2733
2734/*
2735 * Initialize inode-related geometry information.
2736 *
2737 * Compute the inode btree min and max levels and set maxicount.
2738 *
2739 * Set the inode cluster size.  This may still be overridden by the file
2740 * system block size if it is larger than the chosen cluster size.
2741 *
2742 * For v5 filesystems, scale the cluster size with the inode size to keep a
2743 * constant ratio of inode per cluster buffer, but only if mkfs has set the
2744 * inode alignment value appropriately for larger cluster sizes.
2745 *
2746 * Then compute the inode cluster alignment information.
2747 */
2748void
2749xfs_ialloc_setup_geometry(
2750	struct xfs_mount	*mp)
2751{
2752	struct xfs_sb		*sbp = &mp->m_sb;
2753	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2754	uint64_t		icount;
2755	uint			inodes;
2756
2757	igeo->new_diflags2 = 0;
2758	if (xfs_has_bigtime(mp))
2759		igeo->new_diflags2 |= XFS_DIFLAG2_BIGTIME;
2760	if (xfs_has_large_extent_counts(mp))
2761		igeo->new_diflags2 |= XFS_DIFLAG2_NREXT64;
2762
2763	/* Compute inode btree geometry. */
2764	igeo->agino_log = sbp->sb_inopblog + sbp->sb_agblklog;
2765	igeo->inobt_mxr[0] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 1);
2766	igeo->inobt_mxr[1] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 0);
2767	igeo->inobt_mnr[0] = igeo->inobt_mxr[0] / 2;
2768	igeo->inobt_mnr[1] = igeo->inobt_mxr[1] / 2;
2769
2770	igeo->ialloc_inos = max_t(uint16_t, XFS_INODES_PER_CHUNK,
2771			sbp->sb_inopblock);
2772	igeo->ialloc_blks = igeo->ialloc_inos >> sbp->sb_inopblog;
2773
2774	if (sbp->sb_spino_align)
2775		igeo->ialloc_min_blks = sbp->sb_spino_align;
2776	else
2777		igeo->ialloc_min_blks = igeo->ialloc_blks;
2778
2779	/* Compute and fill in value of m_ino_geo.inobt_maxlevels. */
2780	inodes = (1LL << XFS_INO_AGINO_BITS(mp)) >> XFS_INODES_PER_CHUNK_LOG;
2781	igeo->inobt_maxlevels = xfs_btree_compute_maxlevels(igeo->inobt_mnr,
2782			inodes);
2783	ASSERT(igeo->inobt_maxlevels <= xfs_iallocbt_maxlevels_ondisk());
2784
2785	/*
2786	 * Set the maximum inode count for this filesystem, being careful not
2787	 * to use obviously garbage sb_inopblog/sb_inopblock values.  Regular
2788	 * users should never get here due to failing sb verification, but
2789	 * certain users (xfs_db) need to be usable even with corrupt metadata.
2790	 */
2791	if (sbp->sb_imax_pct && igeo->ialloc_blks) {
2792		/*
2793		 * Make sure the maximum inode count is a multiple
2794		 * of the units we allocate inodes in.
2795		 */
2796		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
2797		do_div(icount, 100);
2798		do_div(icount, igeo->ialloc_blks);
2799		igeo->maxicount = XFS_FSB_TO_INO(mp,
2800				icount * igeo->ialloc_blks);
2801	} else {
2802		igeo->maxicount = 0;
2803	}
2804
2805	/*
2806	 * Compute the desired size of an inode cluster buffer size, which
2807	 * starts at 8K and (on v5 filesystems) scales up with larger inode
2808	 * sizes.
2809	 *
2810	 * Preserve the desired inode cluster size because the sparse inodes
2811	 * feature uses that desired size (not the actual size) to compute the
2812	 * sparse inode alignment.  The mount code validates this value, so we
2813	 * cannot change the behavior.
2814	 */
2815	igeo->inode_cluster_size_raw = XFS_INODE_BIG_CLUSTER_SIZE;
2816	if (xfs_has_v3inodes(mp)) {
2817		int	new_size = igeo->inode_cluster_size_raw;
2818
2819		new_size *= mp->m_sb.sb_inodesize / XFS_DINODE_MIN_SIZE;
2820		if (mp->m_sb.sb_inoalignmt >= XFS_B_TO_FSBT(mp, new_size))
2821			igeo->inode_cluster_size_raw = new_size;
2822	}
2823
2824	/* Calculate inode cluster ratios. */
2825	if (igeo->inode_cluster_size_raw > mp->m_sb.sb_blocksize)
2826		igeo->blocks_per_cluster = XFS_B_TO_FSBT(mp,
2827				igeo->inode_cluster_size_raw);
2828	else
2829		igeo->blocks_per_cluster = 1;
2830	igeo->inode_cluster_size = XFS_FSB_TO_B(mp, igeo->blocks_per_cluster);
2831	igeo->inodes_per_cluster = XFS_FSB_TO_INO(mp, igeo->blocks_per_cluster);
2832
2833	/* Calculate inode cluster alignment. */
2834	if (xfs_has_align(mp) &&
2835	    mp->m_sb.sb_inoalignmt >= igeo->blocks_per_cluster)
2836		igeo->cluster_align = mp->m_sb.sb_inoalignmt;
2837	else
2838		igeo->cluster_align = 1;
2839	igeo->inoalign_mask = igeo->cluster_align - 1;
2840	igeo->cluster_align_inodes = XFS_FSB_TO_INO(mp, igeo->cluster_align);
2841
2842	/*
2843	 * If we are using stripe alignment, check whether
2844	 * the stripe unit is a multiple of the inode alignment
2845	 */
2846	if (mp->m_dalign && igeo->inoalign_mask &&
2847	    !(mp->m_dalign & igeo->inoalign_mask))
2848		igeo->ialloc_align = mp->m_dalign;
2849	else
2850		igeo->ialloc_align = 0;
2851}
2852
2853/* Compute the location of the root directory inode that is laid out by mkfs. */
2854xfs_ino_t
2855xfs_ialloc_calc_rootino(
2856	struct xfs_mount	*mp,
2857	int			sunit)
2858{
2859	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2860	xfs_agblock_t		first_bno;
2861
2862	/*
2863	 * Pre-calculate the geometry of AG 0.  We know what it looks like
2864	 * because libxfs knows how to create allocation groups now.
2865	 *
2866	 * first_bno is the first block in which mkfs could possibly have
2867	 * allocated the root directory inode, once we factor in the metadata
2868	 * that mkfs formats before it.  Namely, the four AG headers...
2869	 */
2870	first_bno = howmany(4 * mp->m_sb.sb_sectsize, mp->m_sb.sb_blocksize);
2871
2872	/* ...the two free space btree roots... */
2873	first_bno += 2;
2874
2875	/* ...the inode btree root... */
2876	first_bno += 1;
2877
2878	/* ...the initial AGFL... */
2879	first_bno += xfs_alloc_min_freelist(mp, NULL);
2880
2881	/* ...the free inode btree root... */
2882	if (xfs_has_finobt(mp))
2883		first_bno++;
2884
2885	/* ...the reverse mapping btree root... */
2886	if (xfs_has_rmapbt(mp))
2887		first_bno++;
2888
2889	/* ...the reference count btree... */
2890	if (xfs_has_reflink(mp))
2891		first_bno++;
2892
2893	/*
2894	 * ...and the log, if it is allocated in the first allocation group.
2895	 *
2896	 * This can happen with filesystems that only have a single
2897	 * allocation group, or very odd geometries created by old mkfs
2898	 * versions on very small filesystems.
2899	 */
2900	if (xfs_ag_contains_log(mp, 0))
2901		 first_bno += mp->m_sb.sb_logblocks;
2902
2903	/*
2904	 * Now round first_bno up to whatever allocation alignment is given
2905	 * by the filesystem or was passed in.
2906	 */
2907	if (xfs_has_dalign(mp) && igeo->ialloc_align > 0)
2908		first_bno = roundup(first_bno, sunit);
2909	else if (xfs_has_align(mp) &&
2910			mp->m_sb.sb_inoalignmt > 1)
2911		first_bno = roundup(first_bno, mp->m_sb.sb_inoalignmt);
2912
2913	return XFS_AGINO_TO_INO(mp, 0, XFS_AGB_TO_AGINO(mp, first_bno));
2914}
2915
2916/*
2917 * Ensure there are not sparse inode clusters that cross the new EOAG.
2918 *
2919 * This is a no-op for non-spinode filesystems since clusters are always fully
2920 * allocated and checking the bnobt suffices.  However, a spinode filesystem
2921 * could have a record where the upper inodes are free blocks.  If those blocks
2922 * were removed from the filesystem, the inode record would extend beyond EOAG,
2923 * which will be flagged as corruption.
2924 */
2925int
2926xfs_ialloc_check_shrink(
 
2927	struct xfs_trans	*tp,
2928	xfs_agnumber_t		agno,
2929	struct xfs_buf		*agibp,
2930	xfs_agblock_t		new_length)
2931{
2932	struct xfs_inobt_rec_incore rec;
2933	struct xfs_btree_cur	*cur;
2934	struct xfs_mount	*mp = tp->t_mountp;
2935	struct xfs_perag	*pag;
2936	xfs_agino_t		agino = XFS_AGB_TO_AGINO(mp, new_length);
2937	int			has;
2938	int			error;
2939
2940	if (!xfs_has_sparseinodes(mp))
2941		return 0;
2942
2943	pag = xfs_perag_get(mp, agno);
2944	cur = xfs_inobt_init_cursor(mp, tp, agibp, pag, XFS_BTNUM_INO);
2945
2946	/* Look up the inobt record that would correspond to the new EOFS. */
 
2947	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &has);
2948	if (error || !has)
2949		goto out;
2950
2951	error = xfs_inobt_get_rec(cur, &rec, &has);
2952	if (error)
2953		goto out;
2954
2955	if (!has) {
 
2956		error = -EFSCORRUPTED;
2957		goto out;
2958	}
2959
2960	/* If the record covers inodes that would be beyond EOFS, bail out. */
2961	if (rec.ir_startino + XFS_INODES_PER_CHUNK > agino) {
2962		error = -ENOSPC;
2963		goto out;
2964	}
2965out:
2966	xfs_btree_del_cursor(cur, error);
2967	xfs_perag_put(pag);
2968	return error;
2969}
v6.9.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
   4 * All Rights Reserved.
   5 */
   6#include "xfs.h"
   7#include "xfs_fs.h"
   8#include "xfs_shared.h"
   9#include "xfs_format.h"
  10#include "xfs_log_format.h"
  11#include "xfs_trans_resv.h"
  12#include "xfs_bit.h"
  13#include "xfs_mount.h"
  14#include "xfs_inode.h"
  15#include "xfs_btree.h"
  16#include "xfs_ialloc.h"
  17#include "xfs_ialloc_btree.h"
  18#include "xfs_alloc.h"
  19#include "xfs_errortag.h"
  20#include "xfs_error.h"
  21#include "xfs_bmap.h"
  22#include "xfs_trans.h"
  23#include "xfs_buf_item.h"
  24#include "xfs_icreate_item.h"
  25#include "xfs_icache.h"
  26#include "xfs_trace.h"
  27#include "xfs_log.h"
  28#include "xfs_rmap.h"
  29#include "xfs_ag.h"
  30#include "xfs_health.h"
  31
  32/*
  33 * Lookup a record by ino in the btree given by cur.
  34 */
  35int					/* error */
  36xfs_inobt_lookup(
  37	struct xfs_btree_cur	*cur,	/* btree cursor */
  38	xfs_agino_t		ino,	/* starting inode of chunk */
  39	xfs_lookup_t		dir,	/* <=, >=, == */
  40	int			*stat)	/* success/failure */
  41{
  42	cur->bc_rec.i.ir_startino = ino;
  43	cur->bc_rec.i.ir_holemask = 0;
  44	cur->bc_rec.i.ir_count = 0;
  45	cur->bc_rec.i.ir_freecount = 0;
  46	cur->bc_rec.i.ir_free = 0;
  47	return xfs_btree_lookup(cur, dir, stat);
  48}
  49
  50/*
  51 * Update the record referred to by cur to the value given.
  52 * This either works (return 0) or gets an EFSCORRUPTED error.
  53 */
  54STATIC int				/* error */
  55xfs_inobt_update(
  56	struct xfs_btree_cur	*cur,	/* btree cursor */
  57	xfs_inobt_rec_incore_t	*irec)	/* btree record */
  58{
  59	union xfs_btree_rec	rec;
  60
  61	rec.inobt.ir_startino = cpu_to_be32(irec->ir_startino);
  62	if (xfs_has_sparseinodes(cur->bc_mp)) {
  63		rec.inobt.ir_u.sp.ir_holemask = cpu_to_be16(irec->ir_holemask);
  64		rec.inobt.ir_u.sp.ir_count = irec->ir_count;
  65		rec.inobt.ir_u.sp.ir_freecount = irec->ir_freecount;
  66	} else {
  67		/* ir_holemask/ir_count not supported on-disk */
  68		rec.inobt.ir_u.f.ir_freecount = cpu_to_be32(irec->ir_freecount);
  69	}
  70	rec.inobt.ir_free = cpu_to_be64(irec->ir_free);
  71	return xfs_btree_update(cur, &rec);
  72}
  73
  74/* Convert on-disk btree record to incore inobt record. */
  75void
  76xfs_inobt_btrec_to_irec(
  77	struct xfs_mount		*mp,
  78	const union xfs_btree_rec	*rec,
  79	struct xfs_inobt_rec_incore	*irec)
  80{
  81	irec->ir_startino = be32_to_cpu(rec->inobt.ir_startino);
  82	if (xfs_has_sparseinodes(mp)) {
  83		irec->ir_holemask = be16_to_cpu(rec->inobt.ir_u.sp.ir_holemask);
  84		irec->ir_count = rec->inobt.ir_u.sp.ir_count;
  85		irec->ir_freecount = rec->inobt.ir_u.sp.ir_freecount;
  86	} else {
  87		/*
  88		 * ir_holemask/ir_count not supported on-disk. Fill in hardcoded
  89		 * values for full inode chunks.
  90		 */
  91		irec->ir_holemask = XFS_INOBT_HOLEMASK_FULL;
  92		irec->ir_count = XFS_INODES_PER_CHUNK;
  93		irec->ir_freecount =
  94				be32_to_cpu(rec->inobt.ir_u.f.ir_freecount);
  95	}
  96	irec->ir_free = be64_to_cpu(rec->inobt.ir_free);
  97}
  98
  99/* Compute the freecount of an incore inode record. */
 100uint8_t
 101xfs_inobt_rec_freecount(
 102	const struct xfs_inobt_rec_incore	*irec)
 103{
 104	uint64_t				realfree = irec->ir_free;
 105
 106	if (xfs_inobt_issparse(irec->ir_holemask))
 107		realfree &= xfs_inobt_irec_to_allocmask(irec);
 108	return hweight64(realfree);
 109}
 110
 111/* Simple checks for inode records. */
 112xfs_failaddr_t
 113xfs_inobt_check_irec(
 114	struct xfs_perag			*pag,
 115	const struct xfs_inobt_rec_incore	*irec)
 116{
 117	/* Record has to be properly aligned within the AG. */
 118	if (!xfs_verify_agino(pag, irec->ir_startino))
 119		return __this_address;
 120	if (!xfs_verify_agino(pag,
 121				irec->ir_startino + XFS_INODES_PER_CHUNK - 1))
 122		return __this_address;
 123	if (irec->ir_count < XFS_INODES_PER_HOLEMASK_BIT ||
 124	    irec->ir_count > XFS_INODES_PER_CHUNK)
 125		return __this_address;
 126	if (irec->ir_freecount > XFS_INODES_PER_CHUNK)
 127		return __this_address;
 128
 129	if (xfs_inobt_rec_freecount(irec) != irec->ir_freecount)
 130		return __this_address;
 131
 132	return NULL;
 133}
 134
 135static inline int
 136xfs_inobt_complain_bad_rec(
 137	struct xfs_btree_cur		*cur,
 138	xfs_failaddr_t			fa,
 139	const struct xfs_inobt_rec_incore *irec)
 140{
 141	struct xfs_mount		*mp = cur->bc_mp;
 142
 143	xfs_warn(mp,
 144		"%sbt record corruption in AG %d detected at %pS!",
 145		cur->bc_ops->name, cur->bc_ag.pag->pag_agno, fa);
 146	xfs_warn(mp,
 147"start inode 0x%x, count 0x%x, free 0x%x freemask 0x%llx, holemask 0x%x",
 148		irec->ir_startino, irec->ir_count, irec->ir_freecount,
 149		irec->ir_free, irec->ir_holemask);
 150	xfs_btree_mark_sick(cur);
 151	return -EFSCORRUPTED;
 152}
 153
 154/*
 155 * Get the data from the pointed-to record.
 156 */
 157int
 158xfs_inobt_get_rec(
 159	struct xfs_btree_cur		*cur,
 160	struct xfs_inobt_rec_incore	*irec,
 161	int				*stat)
 162{
 163	struct xfs_mount		*mp = cur->bc_mp;
 164	union xfs_btree_rec		*rec;
 165	xfs_failaddr_t			fa;
 166	int				error;
 
 167
 168	error = xfs_btree_get_rec(cur, &rec, stat);
 169	if (error || *stat == 0)
 170		return error;
 171
 172	xfs_inobt_btrec_to_irec(mp, rec, irec);
 173	fa = xfs_inobt_check_irec(cur->bc_ag.pag, irec);
 174	if (fa)
 175		return xfs_inobt_complain_bad_rec(cur, fa, irec);
 
 
 
 
 
 
 
 
 
 
 
 
 
 176
 177	return 0;
 
 
 
 
 
 
 
 
 
 
 
 178}
 179
 180/*
 181 * Insert a single inobt record. Cursor must already point to desired location.
 182 */
 183int
 184xfs_inobt_insert_rec(
 185	struct xfs_btree_cur	*cur,
 186	uint16_t		holemask,
 187	uint8_t			count,
 188	int32_t			freecount,
 189	xfs_inofree_t		free,
 190	int			*stat)
 191{
 192	cur->bc_rec.i.ir_holemask = holemask;
 193	cur->bc_rec.i.ir_count = count;
 194	cur->bc_rec.i.ir_freecount = freecount;
 195	cur->bc_rec.i.ir_free = free;
 196	return xfs_btree_insert(cur, stat);
 197}
 198
 199/*
 200 * Insert records describing a newly allocated inode chunk into the inobt.
 201 */
 202STATIC int
 203xfs_inobt_insert(
 204	struct xfs_perag	*pag,
 205	struct xfs_trans	*tp,
 206	struct xfs_buf		*agbp,
 
 207	xfs_agino_t		newino,
 208	xfs_agino_t		newlen,
 209	bool			is_finobt)
 210{
 211	struct xfs_btree_cur	*cur;
 212	xfs_agino_t		thisino;
 213	int			i;
 214	int			error;
 215
 216	if (is_finobt)
 217		cur = xfs_finobt_init_cursor(pag, tp, agbp);
 218	else
 219		cur = xfs_inobt_init_cursor(pag, tp, agbp);
 220
 221	for (thisino = newino;
 222	     thisino < newino + newlen;
 223	     thisino += XFS_INODES_PER_CHUNK) {
 224		error = xfs_inobt_lookup(cur, thisino, XFS_LOOKUP_EQ, &i);
 225		if (error) {
 226			xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 227			return error;
 228		}
 229		ASSERT(i == 0);
 230
 231		error = xfs_inobt_insert_rec(cur, XFS_INOBT_HOLEMASK_FULL,
 232					     XFS_INODES_PER_CHUNK,
 233					     XFS_INODES_PER_CHUNK,
 234					     XFS_INOBT_ALL_FREE, &i);
 235		if (error) {
 236			xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 237			return error;
 238		}
 239		ASSERT(i == 1);
 240	}
 241
 242	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 243
 244	return 0;
 245}
 246
 247/*
 248 * Verify that the number of free inodes in the AGI is correct.
 249 */
 250#ifdef DEBUG
 251static int
 252xfs_check_agi_freecount(
 253	struct xfs_btree_cur	*cur)
 254{
 255	if (cur->bc_nlevels == 1) {
 256		xfs_inobt_rec_incore_t rec;
 257		int		freecount = 0;
 258		int		error;
 259		int		i;
 260
 261		error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
 262		if (error)
 263			return error;
 264
 265		do {
 266			error = xfs_inobt_get_rec(cur, &rec, &i);
 267			if (error)
 268				return error;
 269
 270			if (i) {
 271				freecount += rec.ir_freecount;
 272				error = xfs_btree_increment(cur, 0, &i);
 273				if (error)
 274					return error;
 275			}
 276		} while (i == 1);
 277
 278		if (!xfs_is_shutdown(cur->bc_mp))
 279			ASSERT(freecount == cur->bc_ag.pag->pagi_freecount);
 280	}
 281	return 0;
 282}
 283#else
 284#define xfs_check_agi_freecount(cur)	0
 285#endif
 286
 287/*
 288 * Initialise a new set of inodes. When called without a transaction context
 289 * (e.g. from recovery) we initiate a delayed write of the inode buffers rather
 290 * than logging them (which in a transaction context puts them into the AIL
 291 * for writeback rather than the xfsbufd queue).
 292 */
 293int
 294xfs_ialloc_inode_init(
 295	struct xfs_mount	*mp,
 296	struct xfs_trans	*tp,
 297	struct list_head	*buffer_list,
 298	int			icount,
 299	xfs_agnumber_t		agno,
 300	xfs_agblock_t		agbno,
 301	xfs_agblock_t		length,
 302	unsigned int		gen)
 303{
 304	struct xfs_buf		*fbuf;
 305	struct xfs_dinode	*free;
 306	int			nbufs;
 307	int			version;
 308	int			i, j;
 309	xfs_daddr_t		d;
 310	xfs_ino_t		ino = 0;
 311	int			error;
 312
 313	/*
 314	 * Loop over the new block(s), filling in the inodes.  For small block
 315	 * sizes, manipulate the inodes in buffers  which are multiples of the
 316	 * blocks size.
 317	 */
 318	nbufs = length / M_IGEO(mp)->blocks_per_cluster;
 319
 320	/*
 321	 * Figure out what version number to use in the inodes we create.  If
 322	 * the superblock version has caught up to the one that supports the new
 323	 * inode format, then use the new inode version.  Otherwise use the old
 324	 * version so that old kernels will continue to be able to use the file
 325	 * system.
 326	 *
 327	 * For v3 inodes, we also need to write the inode number into the inode,
 328	 * so calculate the first inode number of the chunk here as
 329	 * XFS_AGB_TO_AGINO() only works within a filesystem block, not
 330	 * across multiple filesystem blocks (such as a cluster) and so cannot
 331	 * be used in the cluster buffer loop below.
 332	 *
 333	 * Further, because we are writing the inode directly into the buffer
 334	 * and calculating a CRC on the entire inode, we have ot log the entire
 335	 * inode so that the entire range the CRC covers is present in the log.
 336	 * That means for v3 inode we log the entire buffer rather than just the
 337	 * inode cores.
 338	 */
 339	if (xfs_has_v3inodes(mp)) {
 340		version = 3;
 341		ino = XFS_AGINO_TO_INO(mp, agno, XFS_AGB_TO_AGINO(mp, agbno));
 342
 343		/*
 344		 * log the initialisation that is about to take place as an
 345		 * logical operation. This means the transaction does not
 346		 * need to log the physical changes to the inode buffers as log
 347		 * recovery will know what initialisation is actually needed.
 348		 * Hence we only need to log the buffers as "ordered" buffers so
 349		 * they track in the AIL as if they were physically logged.
 350		 */
 351		if (tp)
 352			xfs_icreate_log(tp, agno, agbno, icount,
 353					mp->m_sb.sb_inodesize, length, gen);
 354	} else
 355		version = 2;
 356
 357	for (j = 0; j < nbufs; j++) {
 358		/*
 359		 * Get the block.
 360		 */
 361		d = XFS_AGB_TO_DADDR(mp, agno, agbno +
 362				(j * M_IGEO(mp)->blocks_per_cluster));
 363		error = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
 364				mp->m_bsize * M_IGEO(mp)->blocks_per_cluster,
 365				XBF_UNMAPPED, &fbuf);
 366		if (error)
 367			return error;
 368
 369		/* Initialize the inode buffers and log them appropriately. */
 370		fbuf->b_ops = &xfs_inode_buf_ops;
 371		xfs_buf_zero(fbuf, 0, BBTOB(fbuf->b_length));
 372		for (i = 0; i < M_IGEO(mp)->inodes_per_cluster; i++) {
 373			int	ioffset = i << mp->m_sb.sb_inodelog;
 374
 375			free = xfs_make_iptr(mp, fbuf, i);
 376			free->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
 377			free->di_version = version;
 378			free->di_gen = cpu_to_be32(gen);
 379			free->di_next_unlinked = cpu_to_be32(NULLAGINO);
 380
 381			if (version == 3) {
 382				free->di_ino = cpu_to_be64(ino);
 383				ino++;
 384				uuid_copy(&free->di_uuid,
 385					  &mp->m_sb.sb_meta_uuid);
 386				xfs_dinode_calc_crc(mp, free);
 387			} else if (tp) {
 388				/* just log the inode core */
 389				xfs_trans_log_buf(tp, fbuf, ioffset,
 390					  ioffset + XFS_DINODE_SIZE(mp) - 1);
 391			}
 392		}
 393
 394		if (tp) {
 395			/*
 396			 * Mark the buffer as an inode allocation buffer so it
 397			 * sticks in AIL at the point of this allocation
 398			 * transaction. This ensures the they are on disk before
 399			 * the tail of the log can be moved past this
 400			 * transaction (i.e. by preventing relogging from moving
 401			 * it forward in the log).
 402			 */
 403			xfs_trans_inode_alloc_buf(tp, fbuf);
 404			if (version == 3) {
 405				/*
 406				 * Mark the buffer as ordered so that they are
 407				 * not physically logged in the transaction but
 408				 * still tracked in the AIL as part of the
 409				 * transaction and pin the log appropriately.
 410				 */
 411				xfs_trans_ordered_buf(tp, fbuf);
 412			}
 413		} else {
 414			fbuf->b_flags |= XBF_DONE;
 415			xfs_buf_delwri_queue(fbuf, buffer_list);
 416			xfs_buf_relse(fbuf);
 417		}
 418	}
 419	return 0;
 420}
 421
 422/*
 423 * Align startino and allocmask for a recently allocated sparse chunk such that
 424 * they are fit for insertion (or merge) into the on-disk inode btrees.
 425 *
 426 * Background:
 427 *
 428 * When enabled, sparse inode support increases the inode alignment from cluster
 429 * size to inode chunk size. This means that the minimum range between two
 430 * non-adjacent inode records in the inobt is large enough for a full inode
 431 * record. This allows for cluster sized, cluster aligned block allocation
 432 * without need to worry about whether the resulting inode record overlaps with
 433 * another record in the tree. Without this basic rule, we would have to deal
 434 * with the consequences of overlap by potentially undoing recent allocations in
 435 * the inode allocation codepath.
 436 *
 437 * Because of this alignment rule (which is enforced on mount), there are two
 438 * inobt possibilities for newly allocated sparse chunks. One is that the
 439 * aligned inode record for the chunk covers a range of inodes not already
 440 * covered in the inobt (i.e., it is safe to insert a new sparse record). The
 441 * other is that a record already exists at the aligned startino that considers
 442 * the newly allocated range as sparse. In the latter case, record content is
 443 * merged in hope that sparse inode chunks fill to full chunks over time.
 444 */
 445STATIC void
 446xfs_align_sparse_ino(
 447	struct xfs_mount		*mp,
 448	xfs_agino_t			*startino,
 449	uint16_t			*allocmask)
 450{
 451	xfs_agblock_t			agbno;
 452	xfs_agblock_t			mod;
 453	int				offset;
 454
 455	agbno = XFS_AGINO_TO_AGBNO(mp, *startino);
 456	mod = agbno % mp->m_sb.sb_inoalignmt;
 457	if (!mod)
 458		return;
 459
 460	/* calculate the inode offset and align startino */
 461	offset = XFS_AGB_TO_AGINO(mp, mod);
 462	*startino -= offset;
 463
 464	/*
 465	 * Since startino has been aligned down, left shift allocmask such that
 466	 * it continues to represent the same physical inodes relative to the
 467	 * new startino.
 468	 */
 469	*allocmask <<= offset / XFS_INODES_PER_HOLEMASK_BIT;
 470}
 471
 472/*
 473 * Determine whether the source inode record can merge into the target. Both
 474 * records must be sparse, the inode ranges must match and there must be no
 475 * allocation overlap between the records.
 476 */
 477STATIC bool
 478__xfs_inobt_can_merge(
 479	struct xfs_inobt_rec_incore	*trec,	/* tgt record */
 480	struct xfs_inobt_rec_incore	*srec)	/* src record */
 481{
 482	uint64_t			talloc;
 483	uint64_t			salloc;
 484
 485	/* records must cover the same inode range */
 486	if (trec->ir_startino != srec->ir_startino)
 487		return false;
 488
 489	/* both records must be sparse */
 490	if (!xfs_inobt_issparse(trec->ir_holemask) ||
 491	    !xfs_inobt_issparse(srec->ir_holemask))
 492		return false;
 493
 494	/* both records must track some inodes */
 495	if (!trec->ir_count || !srec->ir_count)
 496		return false;
 497
 498	/* can't exceed capacity of a full record */
 499	if (trec->ir_count + srec->ir_count > XFS_INODES_PER_CHUNK)
 500		return false;
 501
 502	/* verify there is no allocation overlap */
 503	talloc = xfs_inobt_irec_to_allocmask(trec);
 504	salloc = xfs_inobt_irec_to_allocmask(srec);
 505	if (talloc & salloc)
 506		return false;
 507
 508	return true;
 509}
 510
 511/*
 512 * Merge the source inode record into the target. The caller must call
 513 * __xfs_inobt_can_merge() to ensure the merge is valid.
 514 */
 515STATIC void
 516__xfs_inobt_rec_merge(
 517	struct xfs_inobt_rec_incore	*trec,	/* target */
 518	struct xfs_inobt_rec_incore	*srec)	/* src */
 519{
 520	ASSERT(trec->ir_startino == srec->ir_startino);
 521
 522	/* combine the counts */
 523	trec->ir_count += srec->ir_count;
 524	trec->ir_freecount += srec->ir_freecount;
 525
 526	/*
 527	 * Merge the holemask and free mask. For both fields, 0 bits refer to
 528	 * allocated inodes. We combine the allocated ranges with bitwise AND.
 529	 */
 530	trec->ir_holemask &= srec->ir_holemask;
 531	trec->ir_free &= srec->ir_free;
 532}
 533
 534/*
 535 * Insert a new sparse inode chunk into the associated inode allocation btree.
 536 * The inode record for the sparse chunk is pre-aligned to a startino that
 537 * should match any pre-existing sparse inode record in the tree. This allows
 538 * sparse chunks to fill over time.
 539 *
 540 * If no preexisting record exists, the provided record is inserted.
 541 * If there is a preexisting record, the provided record is merged with the
 542 * existing record and updated in place. The merged record is returned in nrec.
 
 
 543 *
 544 * It is considered corruption if a merge is requested and not possible. Given
 545 * the sparse inode alignment constraints, this should never happen.
 546 */
 547STATIC int
 548xfs_inobt_insert_sprec(
 549	struct xfs_perag		*pag,
 550	struct xfs_trans		*tp,
 551	struct xfs_buf			*agbp,
 552	struct xfs_inobt_rec_incore	*nrec)	/* in/out: new/merged rec. */
 
 
 
 553{
 554	struct xfs_mount		*mp = pag->pag_mount;
 555	struct xfs_btree_cur		*cur;
 556	int				error;
 557	int				i;
 558	struct xfs_inobt_rec_incore	rec;
 559
 560	cur = xfs_inobt_init_cursor(pag, tp, agbp);
 561
 562	/* the new record is pre-aligned so we know where to look */
 563	error = xfs_inobt_lookup(cur, nrec->ir_startino, XFS_LOOKUP_EQ, &i);
 564	if (error)
 565		goto error;
 566	/* if nothing there, insert a new record and return */
 567	if (i == 0) {
 568		error = xfs_inobt_insert_rec(cur, nrec->ir_holemask,
 569					     nrec->ir_count, nrec->ir_freecount,
 570					     nrec->ir_free, &i);
 571		if (error)
 572			goto error;
 573		if (XFS_IS_CORRUPT(mp, i != 1)) {
 574			xfs_btree_mark_sick(cur);
 575			error = -EFSCORRUPTED;
 576			goto error;
 577		}
 578
 579		goto out;
 580	}
 581
 582	/*
 583	 * A record exists at this startino.  Merge the records.
 
 584	 */
 585	error = xfs_inobt_get_rec(cur, &rec, &i);
 586	if (error)
 587		goto error;
 588	if (XFS_IS_CORRUPT(mp, i != 1)) {
 589		xfs_btree_mark_sick(cur);
 590		error = -EFSCORRUPTED;
 591		goto error;
 592	}
 593	if (XFS_IS_CORRUPT(mp, rec.ir_startino != nrec->ir_startino)) {
 594		xfs_btree_mark_sick(cur);
 595		error = -EFSCORRUPTED;
 596		goto error;
 597	}
 598
 599	/*
 600	 * This should never fail. If we have coexisting records that
 601	 * cannot merge, something is seriously wrong.
 602	 */
 603	if (XFS_IS_CORRUPT(mp, !__xfs_inobt_can_merge(nrec, &rec))) {
 604		xfs_btree_mark_sick(cur);
 605		error = -EFSCORRUPTED;
 606		goto error;
 607	}
 608
 609	trace_xfs_irec_merge_pre(mp, pag->pag_agno, rec.ir_startino,
 610				 rec.ir_holemask, nrec->ir_startino,
 611				 nrec->ir_holemask);
 612
 613	/* merge to nrec to output the updated record */
 614	__xfs_inobt_rec_merge(nrec, &rec);
 615
 616	trace_xfs_irec_merge_post(mp, pag->pag_agno, nrec->ir_startino,
 617				  nrec->ir_holemask);
 618
 619	error = xfs_inobt_rec_check_count(mp, nrec);
 620	if (error)
 621		goto error;
 
 622
 623	error = xfs_inobt_update(cur, nrec);
 624	if (error)
 625		goto error;
 626
 627out:
 628	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 629	return 0;
 630error:
 631	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 632	return error;
 633}
 634
 635/*
 636 * Insert a new sparse inode chunk into the free inode btree. The inode
 637 * record for the sparse chunk is pre-aligned to a startino that should match
 638 * any pre-existing sparse inode record in the tree. This allows sparse chunks
 639 * to fill over time.
 640 *
 641 * The new record is always inserted, overwriting a pre-existing record if
 642 * there is one.
 643 */
 644STATIC int
 645xfs_finobt_insert_sprec(
 646	struct xfs_perag		*pag,
 647	struct xfs_trans		*tp,
 648	struct xfs_buf			*agbp,
 649	struct xfs_inobt_rec_incore	*nrec)	/* in/out: new rec. */
 650{
 651	struct xfs_mount		*mp = pag->pag_mount;
 652	struct xfs_btree_cur		*cur;
 653	int				error;
 654	int				i;
 655
 656	cur = xfs_finobt_init_cursor(pag, tp, agbp);
 657
 658	/* the new record is pre-aligned so we know where to look */
 659	error = xfs_inobt_lookup(cur, nrec->ir_startino, XFS_LOOKUP_EQ, &i);
 660	if (error)
 661		goto error;
 662	/* if nothing there, insert a new record and return */
 663	if (i == 0) {
 664		error = xfs_inobt_insert_rec(cur, nrec->ir_holemask,
 665					     nrec->ir_count, nrec->ir_freecount,
 666					     nrec->ir_free, &i);
 667		if (error)
 668			goto error;
 669		if (XFS_IS_CORRUPT(mp, i != 1)) {
 670			xfs_btree_mark_sick(cur);
 671			error = -EFSCORRUPTED;
 672			goto error;
 673		}
 674	} else {
 675		error = xfs_inobt_update(cur, nrec);
 676		if (error)
 677			goto error;
 678	}
 679
 680	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 681	return 0;
 682error:
 683	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 684	return error;
 685}
 686
 687
 688/*
 689 * Allocate new inodes in the allocation group specified by agbp.  Returns 0 if
 690 * inodes were allocated in this AG; -EAGAIN if there was no space in this AG so
 691 * the caller knows it can try another AG, a hard -ENOSPC when over the maximum
 692 * inode count threshold, or the usual negative error code for other errors.
 693 */
 694STATIC int
 695xfs_ialloc_ag_alloc(
 696	struct xfs_perag	*pag,
 697	struct xfs_trans	*tp,
 698	struct xfs_buf		*agbp)
 
 699{
 700	struct xfs_agi		*agi;
 701	struct xfs_alloc_arg	args;
 702	int			error;
 703	xfs_agino_t		newino;		/* new first inode's number */
 704	xfs_agino_t		newlen;		/* new number of inodes */
 705	int			isaligned = 0;	/* inode allocation at stripe */
 706						/* unit boundary */
 707	/* init. to full chunk */
 708	struct xfs_inobt_rec_incore rec;
 709	struct xfs_ino_geometry	*igeo = M_IGEO(tp->t_mountp);
 710	uint16_t		allocmask = (uint16_t) -1;
 711	int			do_sparse = 0;
 712
 713	memset(&args, 0, sizeof(args));
 714	args.tp = tp;
 715	args.mp = tp->t_mountp;
 716	args.fsbno = NULLFSBLOCK;
 717	args.oinfo = XFS_RMAP_OINFO_INODES;
 718	args.pag = pag;
 719
 720#ifdef DEBUG
 721	/* randomly do sparse inode allocations */
 722	if (xfs_has_sparseinodes(tp->t_mountp) &&
 723	    igeo->ialloc_min_blks < igeo->ialloc_blks)
 724		do_sparse = get_random_u32_below(2);
 725#endif
 726
 727	/*
 728	 * Locking will ensure that we don't have two callers in here
 729	 * at one time.
 730	 */
 731	newlen = igeo->ialloc_inos;
 732	if (igeo->maxicount &&
 733	    percpu_counter_read_positive(&args.mp->m_icount) + newlen >
 734							igeo->maxicount)
 735		return -ENOSPC;
 736	args.minlen = args.maxlen = igeo->ialloc_blks;
 737	/*
 738	 * First try to allocate inodes contiguous with the last-allocated
 739	 * chunk of inodes.  If the filesystem is striped, this will fill
 740	 * an entire stripe unit with inodes.
 741	 */
 742	agi = agbp->b_addr;
 743	newino = be32_to_cpu(agi->agi_newino);
 744	args.agbno = XFS_AGINO_TO_AGBNO(args.mp, newino) +
 745		     igeo->ialloc_blks;
 746	if (do_sparse)
 747		goto sparse_alloc;
 748	if (likely(newino != NULLAGINO &&
 749		  (args.agbno < be32_to_cpu(agi->agi_length)))) {
 
 
 750		args.prod = 1;
 751
 752		/*
 753		 * We need to take into account alignment here to ensure that
 754		 * we don't modify the free list if we fail to have an exact
 755		 * block. If we don't have an exact match, and every oher
 756		 * attempt allocation attempt fails, we'll end up cancelling
 757		 * a dirty transaction and shutting down.
 758		 *
 759		 * For an exact allocation, alignment must be 1,
 760		 * however we need to take cluster alignment into account when
 761		 * fixing up the freelist. Use the minalignslop field to
 762		 * indicate that extra blocks might be required for alignment,
 763		 * but not to use them in the actual exact allocation.
 764		 */
 765		args.alignment = 1;
 766		args.minalignslop = igeo->cluster_align - 1;
 767
 768		/* Allow space for the inode btree to split. */
 769		args.minleft = igeo->inobt_maxlevels;
 770		error = xfs_alloc_vextent_exact_bno(&args,
 771				XFS_AGB_TO_FSB(args.mp, pag->pag_agno,
 772						args.agbno));
 773		if (error)
 774			return error;
 775
 776		/*
 777		 * This request might have dirtied the transaction if the AG can
 778		 * satisfy the request, but the exact block was not available.
 779		 * If the allocation did fail, subsequent requests will relax
 780		 * the exact agbno requirement and increase the alignment
 781		 * instead. It is critical that the total size of the request
 782		 * (len + alignment + slop) does not increase from this point
 783		 * on, so reset minalignslop to ensure it is not included in
 784		 * subsequent requests.
 785		 */
 786		args.minalignslop = 0;
 787	}
 788
 789	if (unlikely(args.fsbno == NULLFSBLOCK)) {
 790		/*
 791		 * Set the alignment for the allocation.
 792		 * If stripe alignment is turned on then align at stripe unit
 793		 * boundary.
 794		 * If the cluster size is smaller than a filesystem block
 795		 * then we're doing I/O for inodes in filesystem block size
 796		 * pieces, so don't need alignment anyway.
 797		 */
 798		isaligned = 0;
 799		if (igeo->ialloc_align) {
 800			ASSERT(!xfs_has_noalign(args.mp));
 801			args.alignment = args.mp->m_dalign;
 802			isaligned = 1;
 803		} else
 804			args.alignment = igeo->cluster_align;
 805		/*
 
 
 
 
 
 
 
 806		 * Allocate a fixed-size extent of inodes.
 807		 */
 
 808		args.prod = 1;
 809		/*
 810		 * Allow space for the inode btree to split.
 811		 */
 812		args.minleft = igeo->inobt_maxlevels;
 813		error = xfs_alloc_vextent_near_bno(&args,
 814				XFS_AGB_TO_FSB(args.mp, pag->pag_agno,
 815						be32_to_cpu(agi->agi_root)));
 816		if (error)
 817			return error;
 818	}
 819
 820	/*
 821	 * If stripe alignment is turned on, then try again with cluster
 822	 * alignment.
 823	 */
 824	if (isaligned && args.fsbno == NULLFSBLOCK) {
 
 
 
 825		args.alignment = igeo->cluster_align;
 826		error = xfs_alloc_vextent_near_bno(&args,
 827				XFS_AGB_TO_FSB(args.mp, pag->pag_agno,
 828						be32_to_cpu(agi->agi_root)));
 829		if (error)
 830			return error;
 831	}
 832
 833	/*
 834	 * Finally, try a sparse allocation if the filesystem supports it and
 835	 * the sparse allocation length is smaller than a full chunk.
 836	 */
 837	if (xfs_has_sparseinodes(args.mp) &&
 838	    igeo->ialloc_min_blks < igeo->ialloc_blks &&
 839	    args.fsbno == NULLFSBLOCK) {
 840sparse_alloc:
 
 
 
 841		args.alignment = args.mp->m_sb.sb_spino_align;
 842		args.prod = 1;
 843
 844		args.minlen = igeo->ialloc_min_blks;
 845		args.maxlen = args.minlen;
 846
 847		/*
 848		 * The inode record will be aligned to full chunk size. We must
 849		 * prevent sparse allocation from AG boundaries that result in
 850		 * invalid inode records, such as records that start at agbno 0
 851		 * or extend beyond the AG.
 852		 *
 853		 * Set min agbno to the first aligned, non-zero agbno and max to
 854		 * the last aligned agbno that is at least one full chunk from
 855		 * the end of the AG.
 856		 */
 857		args.min_agbno = args.mp->m_sb.sb_inoalignmt;
 858		args.max_agbno = round_down(args.mp->m_sb.sb_agblocks,
 859					    args.mp->m_sb.sb_inoalignmt) -
 860				 igeo->ialloc_blks;
 861
 862		error = xfs_alloc_vextent_near_bno(&args,
 863				XFS_AGB_TO_FSB(args.mp, pag->pag_agno,
 864						be32_to_cpu(agi->agi_root)));
 865		if (error)
 866			return error;
 867
 868		newlen = XFS_AGB_TO_AGINO(args.mp, args.len);
 869		ASSERT(newlen <= XFS_INODES_PER_CHUNK);
 870		allocmask = (1 << (newlen / XFS_INODES_PER_HOLEMASK_BIT)) - 1;
 871	}
 872
 873	if (args.fsbno == NULLFSBLOCK)
 874		return -EAGAIN;
 875
 876	ASSERT(args.len == args.minlen);
 877
 878	/*
 879	 * Stamp and write the inode buffers.
 880	 *
 881	 * Seed the new inode cluster with a random generation number. This
 882	 * prevents short-term reuse of generation numbers if a chunk is
 883	 * freed and then immediately reallocated. We use random numbers
 884	 * rather than a linear progression to prevent the next generation
 885	 * number from being easily guessable.
 886	 */
 887	error = xfs_ialloc_inode_init(args.mp, tp, NULL, newlen, pag->pag_agno,
 888			args.agbno, args.len, get_random_u32());
 889
 890	if (error)
 891		return error;
 892	/*
 893	 * Convert the results.
 894	 */
 895	newino = XFS_AGB_TO_AGINO(args.mp, args.agbno);
 896
 897	if (xfs_inobt_issparse(~allocmask)) {
 898		/*
 899		 * We've allocated a sparse chunk. Align the startino and mask.
 900		 */
 901		xfs_align_sparse_ino(args.mp, &newino, &allocmask);
 902
 903		rec.ir_startino = newino;
 904		rec.ir_holemask = ~allocmask;
 905		rec.ir_count = newlen;
 906		rec.ir_freecount = newlen;
 907		rec.ir_free = XFS_INOBT_ALL_FREE;
 908
 909		/*
 910		 * Insert the sparse record into the inobt and allow for a merge
 911		 * if necessary. If a merge does occur, rec is updated to the
 912		 * merged record.
 913		 */
 914		error = xfs_inobt_insert_sprec(pag, tp, agbp, &rec);
 
 915		if (error == -EFSCORRUPTED) {
 916			xfs_alert(args.mp,
 917	"invalid sparse inode record: ino 0x%llx holemask 0x%x count %u",
 918				  XFS_AGINO_TO_INO(args.mp, pag->pag_agno,
 919						   rec.ir_startino),
 920				  rec.ir_holemask, rec.ir_count);
 921			xfs_force_shutdown(args.mp, SHUTDOWN_CORRUPT_INCORE);
 922		}
 923		if (error)
 924			return error;
 925
 926		/*
 927		 * We can't merge the part we've just allocated as for the inobt
 928		 * due to finobt semantics. The original record may or may not
 929		 * exist independent of whether physical inodes exist in this
 930		 * sparse chunk.
 931		 *
 932		 * We must update the finobt record based on the inobt record.
 933		 * rec contains the fully merged and up to date inobt record
 934		 * from the previous call. Set merge false to replace any
 935		 * existing record with this one.
 936		 */
 937		if (xfs_has_finobt(args.mp)) {
 938			error = xfs_finobt_insert_sprec(pag, tp, agbp, &rec);
 
 939			if (error)
 940				return error;
 941		}
 942	} else {
 943		/* full chunk - insert new records to both btrees */
 944		error = xfs_inobt_insert(pag, tp, agbp, newino, newlen, false);
 
 945		if (error)
 946			return error;
 947
 948		if (xfs_has_finobt(args.mp)) {
 949			error = xfs_inobt_insert(pag, tp, agbp, newino,
 950						 newlen, true);
 951			if (error)
 952				return error;
 953		}
 954	}
 955
 956	/*
 957	 * Update AGI counts and newino.
 958	 */
 959	be32_add_cpu(&agi->agi_count, newlen);
 960	be32_add_cpu(&agi->agi_freecount, newlen);
 961	pag->pagi_freecount += newlen;
 962	pag->pagi_count += newlen;
 963	agi->agi_newino = cpu_to_be32(newino);
 964
 965	/*
 966	 * Log allocation group header fields
 967	 */
 968	xfs_ialloc_log_agi(tp, agbp,
 969		XFS_AGI_COUNT | XFS_AGI_FREECOUNT | XFS_AGI_NEWINO);
 970	/*
 971	 * Modify/log superblock values for inode count and inode free count.
 972	 */
 973	xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, (long)newlen);
 974	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, (long)newlen);
 975	return 0;
 976}
 977
 978/*
 979 * Try to retrieve the next record to the left/right from the current one.
 980 */
 981STATIC int
 982xfs_ialloc_next_rec(
 983	struct xfs_btree_cur	*cur,
 984	xfs_inobt_rec_incore_t	*rec,
 985	int			*done,
 986	int			left)
 987{
 988	int                     error;
 989	int			i;
 990
 991	if (left)
 992		error = xfs_btree_decrement(cur, 0, &i);
 993	else
 994		error = xfs_btree_increment(cur, 0, &i);
 995
 996	if (error)
 997		return error;
 998	*done = !i;
 999	if (i) {
1000		error = xfs_inobt_get_rec(cur, rec, &i);
1001		if (error)
1002			return error;
1003		if (XFS_IS_CORRUPT(cur->bc_mp, i != 1)) {
1004			xfs_btree_mark_sick(cur);
1005			return -EFSCORRUPTED;
1006		}
1007	}
1008
1009	return 0;
1010}
1011
1012STATIC int
1013xfs_ialloc_get_rec(
1014	struct xfs_btree_cur	*cur,
1015	xfs_agino_t		agino,
1016	xfs_inobt_rec_incore_t	*rec,
1017	int			*done)
1018{
1019	int                     error;
1020	int			i;
1021
1022	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_EQ, &i);
1023	if (error)
1024		return error;
1025	*done = !i;
1026	if (i) {
1027		error = xfs_inobt_get_rec(cur, rec, &i);
1028		if (error)
1029			return error;
1030		if (XFS_IS_CORRUPT(cur->bc_mp, i != 1)) {
1031			xfs_btree_mark_sick(cur);
1032			return -EFSCORRUPTED;
1033		}
1034	}
1035
1036	return 0;
1037}
1038
1039/*
1040 * Return the offset of the first free inode in the record. If the inode chunk
1041 * is sparsely allocated, we convert the record holemask to inode granularity
1042 * and mask off the unallocated regions from the inode free mask.
1043 */
1044STATIC int
1045xfs_inobt_first_free_inode(
1046	struct xfs_inobt_rec_incore	*rec)
1047{
1048	xfs_inofree_t			realfree;
1049
1050	/* if there are no holes, return the first available offset */
1051	if (!xfs_inobt_issparse(rec->ir_holemask))
1052		return xfs_lowbit64(rec->ir_free);
1053
1054	realfree = xfs_inobt_irec_to_allocmask(rec);
1055	realfree &= rec->ir_free;
1056
1057	return xfs_lowbit64(realfree);
1058}
1059
1060/*
1061 * Allocate an inode using the inobt-only algorithm.
1062 */
1063STATIC int
1064xfs_dialloc_ag_inobt(
1065	struct xfs_perag	*pag,
1066	struct xfs_trans	*tp,
1067	struct xfs_buf		*agbp,
 
1068	xfs_ino_t		parent,
1069	xfs_ino_t		*inop)
1070{
1071	struct xfs_mount	*mp = tp->t_mountp;
1072	struct xfs_agi		*agi = agbp->b_addr;
1073	xfs_agnumber_t		pagno = XFS_INO_TO_AGNO(mp, parent);
1074	xfs_agino_t		pagino = XFS_INO_TO_AGINO(mp, parent);
1075	struct xfs_btree_cur	*cur, *tcur;
1076	struct xfs_inobt_rec_incore rec, trec;
1077	xfs_ino_t		ino;
1078	int			error;
1079	int			offset;
1080	int			i, j;
1081	int			searchdistance = 10;
1082
1083	ASSERT(xfs_perag_initialised_agi(pag));
1084	ASSERT(xfs_perag_allows_inodes(pag));
1085	ASSERT(pag->pagi_freecount > 0);
1086
1087 restart_pagno:
1088	cur = xfs_inobt_init_cursor(pag, tp, agbp);
1089	/*
1090	 * If pagino is 0 (this is the root inode allocation) use newino.
1091	 * This must work because we've just allocated some.
1092	 */
1093	if (!pagino)
1094		pagino = be32_to_cpu(agi->agi_newino);
1095
1096	error = xfs_check_agi_freecount(cur);
1097	if (error)
1098		goto error0;
1099
1100	/*
1101	 * If in the same AG as the parent, try to get near the parent.
1102	 */
1103	if (pagno == pag->pag_agno) {
1104		int		doneleft;	/* done, to the left */
1105		int		doneright;	/* done, to the right */
1106
1107		error = xfs_inobt_lookup(cur, pagino, XFS_LOOKUP_LE, &i);
1108		if (error)
1109			goto error0;
1110		if (XFS_IS_CORRUPT(mp, i != 1)) {
1111			xfs_btree_mark_sick(cur);
1112			error = -EFSCORRUPTED;
1113			goto error0;
1114		}
1115
1116		error = xfs_inobt_get_rec(cur, &rec, &j);
1117		if (error)
1118			goto error0;
1119		if (XFS_IS_CORRUPT(mp, j != 1)) {
1120			xfs_btree_mark_sick(cur);
1121			error = -EFSCORRUPTED;
1122			goto error0;
1123		}
1124
1125		if (rec.ir_freecount > 0) {
1126			/*
1127			 * Found a free inode in the same chunk
1128			 * as the parent, done.
1129			 */
1130			goto alloc_inode;
1131		}
1132
1133
1134		/*
1135		 * In the same AG as parent, but parent's chunk is full.
1136		 */
1137
1138		/* duplicate the cursor, search left & right simultaneously */
1139		error = xfs_btree_dup_cursor(cur, &tcur);
1140		if (error)
1141			goto error0;
1142
1143		/*
1144		 * Skip to last blocks looked up if same parent inode.
1145		 */
1146		if (pagino != NULLAGINO &&
1147		    pag->pagl_pagino == pagino &&
1148		    pag->pagl_leftrec != NULLAGINO &&
1149		    pag->pagl_rightrec != NULLAGINO) {
1150			error = xfs_ialloc_get_rec(tcur, pag->pagl_leftrec,
1151						   &trec, &doneleft);
1152			if (error)
1153				goto error1;
1154
1155			error = xfs_ialloc_get_rec(cur, pag->pagl_rightrec,
1156						   &rec, &doneright);
1157			if (error)
1158				goto error1;
1159		} else {
1160			/* search left with tcur, back up 1 record */
1161			error = xfs_ialloc_next_rec(tcur, &trec, &doneleft, 1);
1162			if (error)
1163				goto error1;
1164
1165			/* search right with cur, go forward 1 record. */
1166			error = xfs_ialloc_next_rec(cur, &rec, &doneright, 0);
1167			if (error)
1168				goto error1;
1169		}
1170
1171		/*
1172		 * Loop until we find an inode chunk with a free inode.
1173		 */
1174		while (--searchdistance > 0 && (!doneleft || !doneright)) {
1175			int	useleft;  /* using left inode chunk this time */
1176
1177			/* figure out the closer block if both are valid. */
1178			if (!doneleft && !doneright) {
1179				useleft = pagino -
1180				 (trec.ir_startino + XFS_INODES_PER_CHUNK - 1) <
1181				  rec.ir_startino - pagino;
1182			} else {
1183				useleft = !doneleft;
1184			}
1185
1186			/* free inodes to the left? */
1187			if (useleft && trec.ir_freecount) {
1188				xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1189				cur = tcur;
1190
1191				pag->pagl_leftrec = trec.ir_startino;
1192				pag->pagl_rightrec = rec.ir_startino;
1193				pag->pagl_pagino = pagino;
1194				rec = trec;
1195				goto alloc_inode;
1196			}
1197
1198			/* free inodes to the right? */
1199			if (!useleft && rec.ir_freecount) {
1200				xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1201
1202				pag->pagl_leftrec = trec.ir_startino;
1203				pag->pagl_rightrec = rec.ir_startino;
1204				pag->pagl_pagino = pagino;
1205				goto alloc_inode;
1206			}
1207
1208			/* get next record to check */
1209			if (useleft) {
1210				error = xfs_ialloc_next_rec(tcur, &trec,
1211								 &doneleft, 1);
1212			} else {
1213				error = xfs_ialloc_next_rec(cur, &rec,
1214								 &doneright, 0);
1215			}
1216			if (error)
1217				goto error1;
1218		}
1219
1220		if (searchdistance <= 0) {
1221			/*
1222			 * Not in range - save last search
1223			 * location and allocate a new inode
1224			 */
1225			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1226			pag->pagl_leftrec = trec.ir_startino;
1227			pag->pagl_rightrec = rec.ir_startino;
1228			pag->pagl_pagino = pagino;
1229
1230		} else {
1231			/*
1232			 * We've reached the end of the btree. because
1233			 * we are only searching a small chunk of the
1234			 * btree each search, there is obviously free
1235			 * inodes closer to the parent inode than we
1236			 * are now. restart the search again.
1237			 */
1238			pag->pagl_pagino = NULLAGINO;
1239			pag->pagl_leftrec = NULLAGINO;
1240			pag->pagl_rightrec = NULLAGINO;
1241			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1242			xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1243			goto restart_pagno;
1244		}
1245	}
1246
1247	/*
1248	 * In a different AG from the parent.
1249	 * See if the most recently allocated block has any free.
1250	 */
1251	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1252		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1253					 XFS_LOOKUP_EQ, &i);
1254		if (error)
1255			goto error0;
1256
1257		if (i == 1) {
1258			error = xfs_inobt_get_rec(cur, &rec, &j);
1259			if (error)
1260				goto error0;
1261
1262			if (j == 1 && rec.ir_freecount > 0) {
1263				/*
1264				 * The last chunk allocated in the group
1265				 * still has a free inode.
1266				 */
1267				goto alloc_inode;
1268			}
1269		}
1270	}
1271
1272	/*
1273	 * None left in the last group, search the whole AG
1274	 */
1275	error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1276	if (error)
1277		goto error0;
1278	if (XFS_IS_CORRUPT(mp, i != 1)) {
1279		xfs_btree_mark_sick(cur);
1280		error = -EFSCORRUPTED;
1281		goto error0;
1282	}
1283
1284	for (;;) {
1285		error = xfs_inobt_get_rec(cur, &rec, &i);
1286		if (error)
1287			goto error0;
1288		if (XFS_IS_CORRUPT(mp, i != 1)) {
1289			xfs_btree_mark_sick(cur);
1290			error = -EFSCORRUPTED;
1291			goto error0;
1292		}
1293		if (rec.ir_freecount > 0)
1294			break;
1295		error = xfs_btree_increment(cur, 0, &i);
1296		if (error)
1297			goto error0;
1298		if (XFS_IS_CORRUPT(mp, i != 1)) {
1299			xfs_btree_mark_sick(cur);
1300			error = -EFSCORRUPTED;
1301			goto error0;
1302		}
1303	}
1304
1305alloc_inode:
1306	offset = xfs_inobt_first_free_inode(&rec);
1307	ASSERT(offset >= 0);
1308	ASSERT(offset < XFS_INODES_PER_CHUNK);
1309	ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1310				   XFS_INODES_PER_CHUNK) == 0);
1311	ino = XFS_AGINO_TO_INO(mp, pag->pag_agno, rec.ir_startino + offset);
1312	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1313	rec.ir_freecount--;
1314	error = xfs_inobt_update(cur, &rec);
1315	if (error)
1316		goto error0;
1317	be32_add_cpu(&agi->agi_freecount, -1);
1318	xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1319	pag->pagi_freecount--;
1320
1321	error = xfs_check_agi_freecount(cur);
1322	if (error)
1323		goto error0;
1324
1325	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1326	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1327	*inop = ino;
1328	return 0;
1329error1:
1330	xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
1331error0:
1332	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1333	return error;
1334}
1335
1336/*
1337 * Use the free inode btree to allocate an inode based on distance from the
1338 * parent. Note that the provided cursor may be deleted and replaced.
1339 */
1340STATIC int
1341xfs_dialloc_ag_finobt_near(
1342	xfs_agino_t			pagino,
1343	struct xfs_btree_cur		**ocur,
1344	struct xfs_inobt_rec_incore	*rec)
1345{
1346	struct xfs_btree_cur		*lcur = *ocur;	/* left search cursor */
1347	struct xfs_btree_cur		*rcur;	/* right search cursor */
1348	struct xfs_inobt_rec_incore	rrec;
1349	int				error;
1350	int				i, j;
1351
1352	error = xfs_inobt_lookup(lcur, pagino, XFS_LOOKUP_LE, &i);
1353	if (error)
1354		return error;
1355
1356	if (i == 1) {
1357		error = xfs_inobt_get_rec(lcur, rec, &i);
1358		if (error)
1359			return error;
1360		if (XFS_IS_CORRUPT(lcur->bc_mp, i != 1)) {
1361			xfs_btree_mark_sick(lcur);
1362			return -EFSCORRUPTED;
1363		}
1364
1365		/*
1366		 * See if we've landed in the parent inode record. The finobt
1367		 * only tracks chunks with at least one free inode, so record
1368		 * existence is enough.
1369		 */
1370		if (pagino >= rec->ir_startino &&
1371		    pagino < (rec->ir_startino + XFS_INODES_PER_CHUNK))
1372			return 0;
1373	}
1374
1375	error = xfs_btree_dup_cursor(lcur, &rcur);
1376	if (error)
1377		return error;
1378
1379	error = xfs_inobt_lookup(rcur, pagino, XFS_LOOKUP_GE, &j);
1380	if (error)
1381		goto error_rcur;
1382	if (j == 1) {
1383		error = xfs_inobt_get_rec(rcur, &rrec, &j);
1384		if (error)
1385			goto error_rcur;
1386		if (XFS_IS_CORRUPT(lcur->bc_mp, j != 1)) {
1387			xfs_btree_mark_sick(lcur);
1388			error = -EFSCORRUPTED;
1389			goto error_rcur;
1390		}
1391	}
1392
1393	if (XFS_IS_CORRUPT(lcur->bc_mp, i != 1 && j != 1)) {
1394		xfs_btree_mark_sick(lcur);
1395		error = -EFSCORRUPTED;
1396		goto error_rcur;
1397	}
1398	if (i == 1 && j == 1) {
1399		/*
1400		 * Both the left and right records are valid. Choose the closer
1401		 * inode chunk to the target.
1402		 */
1403		if ((pagino - rec->ir_startino + XFS_INODES_PER_CHUNK - 1) >
1404		    (rrec.ir_startino - pagino)) {
1405			*rec = rrec;
1406			xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1407			*ocur = rcur;
1408		} else {
1409			xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1410		}
1411	} else if (j == 1) {
1412		/* only the right record is valid */
1413		*rec = rrec;
1414		xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1415		*ocur = rcur;
1416	} else if (i == 1) {
1417		/* only the left record is valid */
1418		xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1419	}
1420
1421	return 0;
1422
1423error_rcur:
1424	xfs_btree_del_cursor(rcur, XFS_BTREE_ERROR);
1425	return error;
1426}
1427
1428/*
1429 * Use the free inode btree to find a free inode based on a newino hint. If
1430 * the hint is NULL, find the first free inode in the AG.
1431 */
1432STATIC int
1433xfs_dialloc_ag_finobt_newino(
1434	struct xfs_agi			*agi,
1435	struct xfs_btree_cur		*cur,
1436	struct xfs_inobt_rec_incore	*rec)
1437{
1438	int error;
1439	int i;
1440
1441	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1442		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1443					 XFS_LOOKUP_EQ, &i);
1444		if (error)
1445			return error;
1446		if (i == 1) {
1447			error = xfs_inobt_get_rec(cur, rec, &i);
1448			if (error)
1449				return error;
1450			if (XFS_IS_CORRUPT(cur->bc_mp, i != 1)) {
1451				xfs_btree_mark_sick(cur);
1452				return -EFSCORRUPTED;
1453			}
1454			return 0;
1455		}
1456	}
1457
1458	/*
1459	 * Find the first inode available in the AG.
1460	 */
1461	error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1462	if (error)
1463		return error;
1464	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1)) {
1465		xfs_btree_mark_sick(cur);
1466		return -EFSCORRUPTED;
1467	}
1468
1469	error = xfs_inobt_get_rec(cur, rec, &i);
1470	if (error)
1471		return error;
1472	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1)) {
1473		xfs_btree_mark_sick(cur);
1474		return -EFSCORRUPTED;
1475	}
1476
1477	return 0;
1478}
1479
1480/*
1481 * Update the inobt based on a modification made to the finobt. Also ensure that
1482 * the records from both trees are equivalent post-modification.
1483 */
1484STATIC int
1485xfs_dialloc_ag_update_inobt(
1486	struct xfs_btree_cur		*cur,	/* inobt cursor */
1487	struct xfs_inobt_rec_incore	*frec,	/* finobt record */
1488	int				offset) /* inode offset */
1489{
1490	struct xfs_inobt_rec_incore	rec;
1491	int				error;
1492	int				i;
1493
1494	error = xfs_inobt_lookup(cur, frec->ir_startino, XFS_LOOKUP_EQ, &i);
1495	if (error)
1496		return error;
1497	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1)) {
1498		xfs_btree_mark_sick(cur);
1499		return -EFSCORRUPTED;
1500	}
1501
1502	error = xfs_inobt_get_rec(cur, &rec, &i);
1503	if (error)
1504		return error;
1505	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1)) {
1506		xfs_btree_mark_sick(cur);
1507		return -EFSCORRUPTED;
1508	}
1509	ASSERT((XFS_AGINO_TO_OFFSET(cur->bc_mp, rec.ir_startino) %
1510				   XFS_INODES_PER_CHUNK) == 0);
1511
1512	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1513	rec.ir_freecount--;
1514
1515	if (XFS_IS_CORRUPT(cur->bc_mp,
1516			   rec.ir_free != frec->ir_free ||
1517			   rec.ir_freecount != frec->ir_freecount)) {
1518		xfs_btree_mark_sick(cur);
1519		return -EFSCORRUPTED;
1520	}
1521
1522	return xfs_inobt_update(cur, &rec);
1523}
1524
1525/*
1526 * Allocate an inode using the free inode btree, if available. Otherwise, fall
1527 * back to the inobt search algorithm.
1528 *
1529 * The caller selected an AG for us, and made sure that free inodes are
1530 * available.
1531 */
1532static int
1533xfs_dialloc_ag(
1534	struct xfs_perag	*pag,
1535	struct xfs_trans	*tp,
1536	struct xfs_buf		*agbp,
 
1537	xfs_ino_t		parent,
1538	xfs_ino_t		*inop)
1539{
1540	struct xfs_mount		*mp = tp->t_mountp;
1541	struct xfs_agi			*agi = agbp->b_addr;
1542	xfs_agnumber_t			pagno = XFS_INO_TO_AGNO(mp, parent);
1543	xfs_agino_t			pagino = XFS_INO_TO_AGINO(mp, parent);
1544	struct xfs_btree_cur		*cur;	/* finobt cursor */
1545	struct xfs_btree_cur		*icur;	/* inobt cursor */
1546	struct xfs_inobt_rec_incore	rec;
1547	xfs_ino_t			ino;
1548	int				error;
1549	int				offset;
1550	int				i;
1551
1552	if (!xfs_has_finobt(mp))
1553		return xfs_dialloc_ag_inobt(pag, tp, agbp, parent, inop);
1554
1555	/*
1556	 * If pagino is 0 (this is the root inode allocation) use newino.
1557	 * This must work because we've just allocated some.
1558	 */
1559	if (!pagino)
1560		pagino = be32_to_cpu(agi->agi_newino);
1561
1562	cur = xfs_finobt_init_cursor(pag, tp, agbp);
1563
1564	error = xfs_check_agi_freecount(cur);
1565	if (error)
1566		goto error_cur;
1567
1568	/*
1569	 * The search algorithm depends on whether we're in the same AG as the
1570	 * parent. If so, find the closest available inode to the parent. If
1571	 * not, consider the agi hint or find the first free inode in the AG.
1572	 */
1573	if (pag->pag_agno == pagno)
1574		error = xfs_dialloc_ag_finobt_near(pagino, &cur, &rec);
1575	else
1576		error = xfs_dialloc_ag_finobt_newino(agi, cur, &rec);
1577	if (error)
1578		goto error_cur;
1579
1580	offset = xfs_inobt_first_free_inode(&rec);
1581	ASSERT(offset >= 0);
1582	ASSERT(offset < XFS_INODES_PER_CHUNK);
1583	ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1584				   XFS_INODES_PER_CHUNK) == 0);
1585	ino = XFS_AGINO_TO_INO(mp, pag->pag_agno, rec.ir_startino + offset);
1586
1587	/*
1588	 * Modify or remove the finobt record.
1589	 */
1590	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1591	rec.ir_freecount--;
1592	if (rec.ir_freecount)
1593		error = xfs_inobt_update(cur, &rec);
1594	else
1595		error = xfs_btree_delete(cur, &i);
1596	if (error)
1597		goto error_cur;
1598
1599	/*
1600	 * The finobt has now been updated appropriately. We haven't updated the
1601	 * agi and superblock yet, so we can create an inobt cursor and validate
1602	 * the original freecount. If all is well, make the equivalent update to
1603	 * the inobt using the finobt record and offset information.
1604	 */
1605	icur = xfs_inobt_init_cursor(pag, tp, agbp);
1606
1607	error = xfs_check_agi_freecount(icur);
1608	if (error)
1609		goto error_icur;
1610
1611	error = xfs_dialloc_ag_update_inobt(icur, &rec, offset);
1612	if (error)
1613		goto error_icur;
1614
1615	/*
1616	 * Both trees have now been updated. We must update the perag and
1617	 * superblock before we can check the freecount for each btree.
1618	 */
1619	be32_add_cpu(&agi->agi_freecount, -1);
1620	xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1621	pag->pagi_freecount--;
1622
1623	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1624
1625	error = xfs_check_agi_freecount(icur);
1626	if (error)
1627		goto error_icur;
1628	error = xfs_check_agi_freecount(cur);
1629	if (error)
1630		goto error_icur;
1631
1632	xfs_btree_del_cursor(icur, XFS_BTREE_NOERROR);
1633	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1634	*inop = ino;
1635	return 0;
1636
1637error_icur:
1638	xfs_btree_del_cursor(icur, XFS_BTREE_ERROR);
1639error_cur:
1640	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1641	return error;
1642}
1643
1644static int
1645xfs_dialloc_roll(
1646	struct xfs_trans	**tpp,
1647	struct xfs_buf		*agibp)
1648{
1649	struct xfs_trans	*tp = *tpp;
1650	struct xfs_dquot_acct	*dqinfo;
1651	int			error;
1652
1653	/*
1654	 * Hold to on to the agibp across the commit so no other allocation can
1655	 * come in and take the free inodes we just allocated for our caller.
1656	 */
1657	xfs_trans_bhold(tp, agibp);
1658
1659	/*
1660	 * We want the quota changes to be associated with the next transaction,
1661	 * NOT this one. So, detach the dqinfo from this and attach it to the
1662	 * next transaction.
1663	 */
1664	dqinfo = tp->t_dqinfo;
1665	tp->t_dqinfo = NULL;
1666
1667	error = xfs_trans_roll(&tp);
1668
1669	/* Re-attach the quota info that we detached from prev trx. */
1670	tp->t_dqinfo = dqinfo;
1671
1672	/*
1673	 * Join the buffer even on commit error so that the buffer is released
1674	 * when the caller cancels the transaction and doesn't have to handle
1675	 * this error case specially.
1676	 */
1677	xfs_trans_bjoin(tp, agibp);
1678	*tpp = tp;
1679	return error;
1680}
1681
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1682static bool
1683xfs_dialloc_good_ag(
 
1684	struct xfs_perag	*pag,
1685	struct xfs_trans	*tp,
1686	umode_t			mode,
1687	int			flags,
1688	bool			ok_alloc)
1689{
1690	struct xfs_mount	*mp = tp->t_mountp;
1691	xfs_extlen_t		ineed;
1692	xfs_extlen_t		longest = 0;
1693	int			needspace;
1694	int			error;
1695
1696	if (!pag)
1697		return false;
1698	if (!xfs_perag_allows_inodes(pag))
1699		return false;
1700
1701	if (!xfs_perag_initialised_agi(pag)) {
1702		error = xfs_ialloc_read_agi(pag, tp, NULL);
1703		if (error)
1704			return false;
1705	}
1706
1707	if (pag->pagi_freecount)
1708		return true;
1709	if (!ok_alloc)
1710		return false;
1711
1712	if (!xfs_perag_initialised_agf(pag)) {
1713		error = xfs_alloc_read_agf(pag, tp, flags, NULL);
1714		if (error)
1715			return false;
1716	}
1717
1718	/*
1719	 * Check that there is enough free space for the file plus a chunk of
1720	 * inodes if we need to allocate some. If this is the first pass across
1721	 * the AGs, take into account the potential space needed for alignment
1722	 * of inode chunks when checking the longest contiguous free space in
1723	 * the AG - this prevents us from getting ENOSPC because we have free
1724	 * space larger than ialloc_blks but alignment constraints prevent us
1725	 * from using it.
1726	 *
1727	 * If we can't find an AG with space for full alignment slack to be
1728	 * taken into account, we must be near ENOSPC in all AGs.  Hence we
1729	 * don't include alignment for the second pass and so if we fail
1730	 * allocation due to alignment issues then it is most likely a real
1731	 * ENOSPC condition.
1732	 *
1733	 * XXX(dgc): this calculation is now bogus thanks to the per-ag
1734	 * reservations that xfs_alloc_fix_freelist() now does via
1735	 * xfs_alloc_space_available(). When the AG fills up, pagf_freeblks will
1736	 * be more than large enough for the check below to succeed, but
1737	 * xfs_alloc_space_available() will fail because of the non-zero
1738	 * metadata reservation and hence we won't actually be able to allocate
1739	 * more inodes in this AG. We do soooo much unnecessary work near ENOSPC
1740	 * because of this.
1741	 */
1742	ineed = M_IGEO(mp)->ialloc_min_blks;
1743	if (flags && ineed > 1)
1744		ineed += M_IGEO(mp)->cluster_align;
1745	longest = pag->pagf_longest;
1746	if (!longest)
1747		longest = pag->pagf_flcount > 0;
1748	needspace = S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode);
1749
1750	if (pag->pagf_freeblks < needspace + ineed || longest < ineed)
1751		return false;
1752	return true;
1753}
1754
1755static int
1756xfs_dialloc_try_ag(
 
1757	struct xfs_perag	*pag,
1758	struct xfs_trans	**tpp,
1759	xfs_ino_t		parent,
1760	xfs_ino_t		*new_ino,
1761	bool			ok_alloc)
1762{
1763	struct xfs_buf		*agbp;
1764	xfs_ino_t		ino;
1765	int			error;
1766
1767	/*
1768	 * Then read in the AGI buffer and recheck with the AGI buffer
1769	 * lock held.
1770	 */
1771	error = xfs_ialloc_read_agi(pag, *tpp, &agbp);
1772	if (error)
1773		return error;
1774
1775	if (!pag->pagi_freecount) {
1776		if (!ok_alloc) {
1777			error = -EAGAIN;
1778			goto out_release;
1779		}
1780
1781		error = xfs_ialloc_ag_alloc(pag, *tpp, agbp);
1782		if (error < 0)
1783			goto out_release;
1784
1785		/*
1786		 * We successfully allocated space for an inode cluster in this
1787		 * AG.  Roll the transaction so that we can allocate one of the
1788		 * new inodes.
1789		 */
1790		ASSERT(pag->pagi_freecount > 0);
1791		error = xfs_dialloc_roll(tpp, agbp);
1792		if (error)
1793			goto out_release;
1794	}
1795
1796	/* Allocate an inode in the found AG */
1797	error = xfs_dialloc_ag(pag, *tpp, agbp, parent, &ino);
1798	if (!error)
1799		*new_ino = ino;
1800	return error;
1801
1802out_release:
1803	xfs_trans_brelse(*tpp, agbp);
1804	return error;
1805}
1806
1807/*
1808 * Allocate an on-disk inode.
1809 *
1810 * Mode is used to tell whether the new inode is a directory and hence where to
1811 * locate it. The on-disk inode that is allocated will be returned in @new_ino
1812 * on success, otherwise an error will be set to indicate the failure (e.g.
1813 * -ENOSPC).
1814 */
1815int
1816xfs_dialloc(
1817	struct xfs_trans	**tpp,
1818	xfs_ino_t		parent,
1819	umode_t			mode,
1820	xfs_ino_t		*new_ino)
1821{
1822	struct xfs_mount	*mp = (*tpp)->t_mountp;
1823	xfs_agnumber_t		agno;
1824	int			error = 0;
1825	xfs_agnumber_t		start_agno;
1826	struct xfs_perag	*pag;
1827	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
1828	bool			ok_alloc = true;
1829	bool			low_space = false;
1830	int			flags;
1831	xfs_ino_t		ino = NULLFSINO;
1832
1833	/*
1834	 * Directories, symlinks, and regular files frequently allocate at least
1835	 * one block, so factor that potential expansion when we examine whether
1836	 * an AG has enough space for file creation.
1837	 */
1838	if (S_ISDIR(mode))
1839		start_agno = (atomic_inc_return(&mp->m_agirotor) - 1) %
1840				mp->m_maxagi;
1841	else {
1842		start_agno = XFS_INO_TO_AGNO(mp, parent);
1843		if (start_agno >= mp->m_maxagi)
1844			start_agno = 0;
1845	}
1846
1847	/*
1848	 * If we have already hit the ceiling of inode blocks then clear
1849	 * ok_alloc so we scan all available agi structures for a free
1850	 * inode.
1851	 *
1852	 * Read rough value of mp->m_icount by percpu_counter_read_positive,
1853	 * which will sacrifice the preciseness but improve the performance.
1854	 */
1855	if (igeo->maxicount &&
1856	    percpu_counter_read_positive(&mp->m_icount) + igeo->ialloc_inos
1857							> igeo->maxicount) {
1858		ok_alloc = false;
1859	}
1860
1861	/*
1862	 * If we are near to ENOSPC, we want to prefer allocation from AGs that
1863	 * have free inodes in them rather than use up free space allocating new
1864	 * inode chunks. Hence we turn off allocation for the first non-blocking
1865	 * pass through the AGs if we are near ENOSPC to consume free inodes
1866	 * that we can immediately allocate, but then we allow allocation on the
1867	 * second pass if we fail to find an AG with free inodes in it.
1868	 */
1869	if (percpu_counter_read_positive(&mp->m_fdblocks) <
1870			mp->m_low_space[XFS_LOWSP_1_PCNT]) {
1871		ok_alloc = false;
1872		low_space = true;
1873	}
1874
1875	/*
1876	 * Loop until we find an allocation group that either has free inodes
1877	 * or in which we can allocate some inodes.  Iterate through the
1878	 * allocation groups upward, wrapping at the end.
1879	 */
 
1880	flags = XFS_ALLOC_FLAG_TRYLOCK;
1881retry:
1882	for_each_perag_wrap_at(mp, start_agno, mp->m_maxagi, agno, pag) {
1883		if (xfs_dialloc_good_ag(pag, *tpp, mode, flags, ok_alloc)) {
1884			error = xfs_dialloc_try_ag(pag, tpp, parent,
1885					&ino, ok_alloc);
1886			if (error != -EAGAIN)
1887				break;
1888			error = 0;
1889		}
1890
1891		if (xfs_is_shutdown(mp)) {
1892			error = -EFSCORRUPTED;
1893			break;
1894		}
1895	}
1896	if (pag)
1897		xfs_perag_rele(pag);
1898	if (error)
1899		return error;
1900	if (ino == NULLFSINO) {
1901		if (flags) {
1902			flags = 0;
1903			if (low_space)
1904				ok_alloc = true;
1905			goto retry;
1906		}
1907		return -ENOSPC;
1908	}
1909	*new_ino = ino;
1910	return 0;
 
 
 
1911}
1912
1913/*
1914 * Free the blocks of an inode chunk. We must consider that the inode chunk
1915 * might be sparse and only free the regions that are allocated as part of the
1916 * chunk.
1917 */
1918static int
1919xfs_difree_inode_chunk(
1920	struct xfs_trans		*tp,
1921	xfs_agnumber_t			agno,
1922	struct xfs_inobt_rec_incore	*rec)
1923{
1924	struct xfs_mount		*mp = tp->t_mountp;
1925	xfs_agblock_t			sagbno = XFS_AGINO_TO_AGBNO(mp,
1926							rec->ir_startino);
1927	int				startidx, endidx;
1928	int				nextbit;
1929	xfs_agblock_t			agbno;
1930	int				contigblk;
1931	DECLARE_BITMAP(holemask, XFS_INOBT_HOLEMASK_BITS);
1932
1933	if (!xfs_inobt_issparse(rec->ir_holemask)) {
1934		/* not sparse, calculate extent info directly */
1935		return xfs_free_extent_later(tp,
1936				XFS_AGB_TO_FSB(mp, agno, sagbno),
1937				M_IGEO(mp)->ialloc_blks, &XFS_RMAP_OINFO_INODES,
1938				XFS_AG_RESV_NONE, false);
1939	}
1940
1941	/* holemask is only 16-bits (fits in an unsigned long) */
1942	ASSERT(sizeof(rec->ir_holemask) <= sizeof(holemask[0]));
1943	holemask[0] = rec->ir_holemask;
1944
1945	/*
1946	 * Find contiguous ranges of zeroes (i.e., allocated regions) in the
1947	 * holemask and convert the start/end index of each range to an extent.
1948	 * We start with the start and end index both pointing at the first 0 in
1949	 * the mask.
1950	 */
1951	startidx = endidx = find_first_zero_bit(holemask,
1952						XFS_INOBT_HOLEMASK_BITS);
1953	nextbit = startidx + 1;
1954	while (startidx < XFS_INOBT_HOLEMASK_BITS) {
1955		int error;
1956
1957		nextbit = find_next_zero_bit(holemask, XFS_INOBT_HOLEMASK_BITS,
1958					     nextbit);
1959		/*
1960		 * If the next zero bit is contiguous, update the end index of
1961		 * the current range and continue.
1962		 */
1963		if (nextbit != XFS_INOBT_HOLEMASK_BITS &&
1964		    nextbit == endidx + 1) {
1965			endidx = nextbit;
1966			goto next;
1967		}
1968
1969		/*
1970		 * nextbit is not contiguous with the current end index. Convert
1971		 * the current start/end to an extent and add it to the free
1972		 * list.
1973		 */
1974		agbno = sagbno + (startidx * XFS_INODES_PER_HOLEMASK_BIT) /
1975				  mp->m_sb.sb_inopblock;
1976		contigblk = ((endidx - startidx + 1) *
1977			     XFS_INODES_PER_HOLEMASK_BIT) /
1978			    mp->m_sb.sb_inopblock;
1979
1980		ASSERT(agbno % mp->m_sb.sb_spino_align == 0);
1981		ASSERT(contigblk % mp->m_sb.sb_spino_align == 0);
1982		error = xfs_free_extent_later(tp,
1983				XFS_AGB_TO_FSB(mp, agno, agbno), contigblk,
1984				&XFS_RMAP_OINFO_INODES, XFS_AG_RESV_NONE,
1985				false);
1986		if (error)
1987			return error;
1988
1989		/* reset range to current bit and carry on... */
1990		startidx = endidx = nextbit;
1991
1992next:
1993		nextbit++;
1994	}
1995	return 0;
1996}
1997
1998STATIC int
1999xfs_difree_inobt(
2000	struct xfs_perag		*pag,
2001	struct xfs_trans		*tp,
2002	struct xfs_buf			*agbp,
 
2003	xfs_agino_t			agino,
2004	struct xfs_icluster		*xic,
2005	struct xfs_inobt_rec_incore	*orec)
2006{
2007	struct xfs_mount		*mp = pag->pag_mount;
2008	struct xfs_agi			*agi = agbp->b_addr;
2009	struct xfs_btree_cur		*cur;
2010	struct xfs_inobt_rec_incore	rec;
2011	int				ilen;
2012	int				error;
2013	int				i;
2014	int				off;
2015
2016	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
2017	ASSERT(XFS_AGINO_TO_AGBNO(mp, agino) < be32_to_cpu(agi->agi_length));
2018
2019	/*
2020	 * Initialize the cursor.
2021	 */
2022	cur = xfs_inobt_init_cursor(pag, tp, agbp);
2023
2024	error = xfs_check_agi_freecount(cur);
2025	if (error)
2026		goto error0;
2027
2028	/*
2029	 * Look for the entry describing this inode.
2030	 */
2031	if ((error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i))) {
2032		xfs_warn(mp, "%s: xfs_inobt_lookup() returned error %d.",
2033			__func__, error);
2034		goto error0;
2035	}
2036	if (XFS_IS_CORRUPT(mp, i != 1)) {
2037		xfs_btree_mark_sick(cur);
2038		error = -EFSCORRUPTED;
2039		goto error0;
2040	}
2041	error = xfs_inobt_get_rec(cur, &rec, &i);
2042	if (error) {
2043		xfs_warn(mp, "%s: xfs_inobt_get_rec() returned error %d.",
2044			__func__, error);
2045		goto error0;
2046	}
2047	if (XFS_IS_CORRUPT(mp, i != 1)) {
2048		xfs_btree_mark_sick(cur);
2049		error = -EFSCORRUPTED;
2050		goto error0;
2051	}
2052	/*
2053	 * Get the offset in the inode chunk.
2054	 */
2055	off = agino - rec.ir_startino;
2056	ASSERT(off >= 0 && off < XFS_INODES_PER_CHUNK);
2057	ASSERT(!(rec.ir_free & XFS_INOBT_MASK(off)));
2058	/*
2059	 * Mark the inode free & increment the count.
2060	 */
2061	rec.ir_free |= XFS_INOBT_MASK(off);
2062	rec.ir_freecount++;
2063
2064	/*
2065	 * When an inode chunk is free, it becomes eligible for removal. Don't
2066	 * remove the chunk if the block size is large enough for multiple inode
2067	 * chunks (that might not be free).
2068	 */
2069	if (!xfs_has_ikeep(mp) && rec.ir_free == XFS_INOBT_ALL_FREE &&
2070	    mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK) {
 
 
2071		xic->deleted = true;
2072		xic->first_ino = XFS_AGINO_TO_INO(mp, pag->pag_agno,
2073				rec.ir_startino);
2074		xic->alloc = xfs_inobt_irec_to_allocmask(&rec);
2075
2076		/*
2077		 * Remove the inode cluster from the AGI B+Tree, adjust the
2078		 * AGI and Superblock inode counts, and mark the disk space
2079		 * to be freed when the transaction is committed.
2080		 */
2081		ilen = rec.ir_freecount;
2082		be32_add_cpu(&agi->agi_count, -ilen);
2083		be32_add_cpu(&agi->agi_freecount, -(ilen - 1));
2084		xfs_ialloc_log_agi(tp, agbp, XFS_AGI_COUNT | XFS_AGI_FREECOUNT);
2085		pag->pagi_freecount -= ilen - 1;
2086		pag->pagi_count -= ilen;
2087		xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, -ilen);
2088		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -(ilen - 1));
2089
2090		if ((error = xfs_btree_delete(cur, &i))) {
2091			xfs_warn(mp, "%s: xfs_btree_delete returned error %d.",
2092				__func__, error);
2093			goto error0;
2094		}
2095
2096		error = xfs_difree_inode_chunk(tp, pag->pag_agno, &rec);
2097		if (error)
2098			goto error0;
2099	} else {
2100		xic->deleted = false;
2101
2102		error = xfs_inobt_update(cur, &rec);
2103		if (error) {
2104			xfs_warn(mp, "%s: xfs_inobt_update returned error %d.",
2105				__func__, error);
2106			goto error0;
2107		}
2108
2109		/*
2110		 * Change the inode free counts and log the ag/sb changes.
2111		 */
2112		be32_add_cpu(&agi->agi_freecount, 1);
2113		xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
2114		pag->pagi_freecount++;
2115		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, 1);
2116	}
2117
2118	error = xfs_check_agi_freecount(cur);
2119	if (error)
2120		goto error0;
2121
2122	*orec = rec;
2123	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2124	return 0;
2125
2126error0:
2127	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2128	return error;
2129}
2130
2131/*
2132 * Free an inode in the free inode btree.
2133 */
2134STATIC int
2135xfs_difree_finobt(
2136	struct xfs_perag		*pag,
2137	struct xfs_trans		*tp,
2138	struct xfs_buf			*agbp,
 
2139	xfs_agino_t			agino,
2140	struct xfs_inobt_rec_incore	*ibtrec) /* inobt record */
2141{
2142	struct xfs_mount		*mp = pag->pag_mount;
2143	struct xfs_btree_cur		*cur;
2144	struct xfs_inobt_rec_incore	rec;
2145	int				offset = agino - ibtrec->ir_startino;
2146	int				error;
2147	int				i;
2148
2149	cur = xfs_finobt_init_cursor(pag, tp, agbp);
2150
2151	error = xfs_inobt_lookup(cur, ibtrec->ir_startino, XFS_LOOKUP_EQ, &i);
2152	if (error)
2153		goto error;
2154	if (i == 0) {
2155		/*
2156		 * If the record does not exist in the finobt, we must have just
2157		 * freed an inode in a previously fully allocated chunk. If not,
2158		 * something is out of sync.
2159		 */
2160		if (XFS_IS_CORRUPT(mp, ibtrec->ir_freecount != 1)) {
2161			xfs_btree_mark_sick(cur);
2162			error = -EFSCORRUPTED;
2163			goto error;
2164		}
2165
2166		error = xfs_inobt_insert_rec(cur, ibtrec->ir_holemask,
2167					     ibtrec->ir_count,
2168					     ibtrec->ir_freecount,
2169					     ibtrec->ir_free, &i);
2170		if (error)
2171			goto error;
2172		ASSERT(i == 1);
2173
2174		goto out;
2175	}
2176
2177	/*
2178	 * Read and update the existing record. We could just copy the ibtrec
2179	 * across here, but that would defeat the purpose of having redundant
2180	 * metadata. By making the modifications independently, we can catch
2181	 * corruptions that we wouldn't see if we just copied from one record
2182	 * to another.
2183	 */
2184	error = xfs_inobt_get_rec(cur, &rec, &i);
2185	if (error)
2186		goto error;
2187	if (XFS_IS_CORRUPT(mp, i != 1)) {
2188		xfs_btree_mark_sick(cur);
2189		error = -EFSCORRUPTED;
2190		goto error;
2191	}
2192
2193	rec.ir_free |= XFS_INOBT_MASK(offset);
2194	rec.ir_freecount++;
2195
2196	if (XFS_IS_CORRUPT(mp,
2197			   rec.ir_free != ibtrec->ir_free ||
2198			   rec.ir_freecount != ibtrec->ir_freecount)) {
2199		xfs_btree_mark_sick(cur);
2200		error = -EFSCORRUPTED;
2201		goto error;
2202	}
2203
2204	/*
2205	 * The content of inobt records should always match between the inobt
2206	 * and finobt. The lifecycle of records in the finobt is different from
2207	 * the inobt in that the finobt only tracks records with at least one
2208	 * free inode. Hence, if all of the inodes are free and we aren't
2209	 * keeping inode chunks permanently on disk, remove the record.
2210	 * Otherwise, update the record with the new information.
2211	 *
2212	 * Note that we currently can't free chunks when the block size is large
2213	 * enough for multiple chunks. Leave the finobt record to remain in sync
2214	 * with the inobt.
2215	 */
2216	if (!xfs_has_ikeep(mp) && rec.ir_free == XFS_INOBT_ALL_FREE &&
2217	    mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK) {
2218		error = xfs_btree_delete(cur, &i);
2219		if (error)
2220			goto error;
2221		ASSERT(i == 1);
2222	} else {
2223		error = xfs_inobt_update(cur, &rec);
2224		if (error)
2225			goto error;
2226	}
2227
2228out:
2229	error = xfs_check_agi_freecount(cur);
2230	if (error)
2231		goto error;
2232
2233	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2234	return 0;
2235
2236error:
2237	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2238	return error;
2239}
2240
2241/*
2242 * Free disk inode.  Carefully avoids touching the incore inode, all
2243 * manipulations incore are the caller's responsibility.
2244 * The on-disk inode is not changed by this operation, only the
2245 * btree (free inode mask) is changed.
2246 */
2247int
2248xfs_difree(
2249	struct xfs_trans	*tp,
2250	struct xfs_perag	*pag,
2251	xfs_ino_t		inode,
2252	struct xfs_icluster	*xic)
2253{
2254	/* REFERENCED */
2255	xfs_agblock_t		agbno;	/* block number containing inode */
2256	struct xfs_buf		*agbp;	/* buffer for allocation group header */
2257	xfs_agino_t		agino;	/* allocation group inode number */
2258	int			error;	/* error return value */
2259	struct xfs_mount	*mp = tp->t_mountp;
2260	struct xfs_inobt_rec_incore rec;/* btree record */
2261
2262	/*
2263	 * Break up inode number into its components.
2264	 */
2265	if (pag->pag_agno != XFS_INO_TO_AGNO(mp, inode)) {
2266		xfs_warn(mp, "%s: agno != pag->pag_agno (%d != %d).",
2267			__func__, XFS_INO_TO_AGNO(mp, inode), pag->pag_agno);
2268		ASSERT(0);
2269		return -EINVAL;
2270	}
2271	agino = XFS_INO_TO_AGINO(mp, inode);
2272	if (inode != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino))  {
2273		xfs_warn(mp, "%s: inode != XFS_AGINO_TO_INO() (%llu != %llu).",
2274			__func__, (unsigned long long)inode,
2275			(unsigned long long)XFS_AGINO_TO_INO(mp, pag->pag_agno, agino));
2276		ASSERT(0);
2277		return -EINVAL;
2278	}
2279	agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2280	if (agbno >= mp->m_sb.sb_agblocks)  {
2281		xfs_warn(mp, "%s: agbno >= mp->m_sb.sb_agblocks (%d >= %d).",
2282			__func__, agbno, mp->m_sb.sb_agblocks);
2283		ASSERT(0);
2284		return -EINVAL;
2285	}
2286	/*
2287	 * Get the allocation group header.
2288	 */
2289	error = xfs_ialloc_read_agi(pag, tp, &agbp);
2290	if (error) {
2291		xfs_warn(mp, "%s: xfs_ialloc_read_agi() returned error %d.",
2292			__func__, error);
2293		return error;
2294	}
2295
2296	/*
2297	 * Fix up the inode allocation btree.
2298	 */
2299	error = xfs_difree_inobt(pag, tp, agbp, agino, xic, &rec);
2300	if (error)
2301		goto error0;
2302
2303	/*
2304	 * Fix up the free inode btree.
2305	 */
2306	if (xfs_has_finobt(mp)) {
2307		error = xfs_difree_finobt(pag, tp, agbp, agino, &rec);
2308		if (error)
2309			goto error0;
2310	}
2311
2312	return 0;
2313
2314error0:
2315	return error;
2316}
2317
2318STATIC int
2319xfs_imap_lookup(
 
 
2320	struct xfs_perag	*pag,
2321	struct xfs_trans	*tp,
2322	xfs_agino_t		agino,
2323	xfs_agblock_t		agbno,
2324	xfs_agblock_t		*chunk_agbno,
2325	xfs_agblock_t		*offset_agbno,
2326	int			flags)
2327{
2328	struct xfs_mount	*mp = pag->pag_mount;
2329	struct xfs_inobt_rec_incore rec;
2330	struct xfs_btree_cur	*cur;
2331	struct xfs_buf		*agbp;
2332	int			error;
2333	int			i;
2334
2335	error = xfs_ialloc_read_agi(pag, tp, &agbp);
2336	if (error) {
2337		xfs_alert(mp,
2338			"%s: xfs_ialloc_read_agi() returned error %d, agno %d",
2339			__func__, error, pag->pag_agno);
2340		return error;
2341	}
2342
2343	/*
2344	 * Lookup the inode record for the given agino. If the record cannot be
2345	 * found, then it's an invalid inode number and we should abort. Once
2346	 * we have a record, we need to ensure it contains the inode number
2347	 * we are looking up.
2348	 */
2349	cur = xfs_inobt_init_cursor(pag, tp, agbp);
2350	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i);
2351	if (!error) {
2352		if (i)
2353			error = xfs_inobt_get_rec(cur, &rec, &i);
2354		if (!error && i == 0)
2355			error = -EINVAL;
2356	}
2357
2358	xfs_trans_brelse(tp, agbp);
2359	xfs_btree_del_cursor(cur, error);
2360	if (error)
2361		return error;
2362
2363	/* check that the returned record contains the required inode */
2364	if (rec.ir_startino > agino ||
2365	    rec.ir_startino + M_IGEO(mp)->ialloc_inos <= agino)
2366		return -EINVAL;
2367
2368	/* for untrusted inodes check it is allocated first */
2369	if ((flags & XFS_IGET_UNTRUSTED) &&
2370	    (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino)))
2371		return -EINVAL;
2372
2373	*chunk_agbno = XFS_AGINO_TO_AGBNO(mp, rec.ir_startino);
2374	*offset_agbno = agbno - *chunk_agbno;
2375	return 0;
2376}
2377
2378/*
2379 * Return the location of the inode in imap, for mapping it into a buffer.
2380 */
2381int
2382xfs_imap(
2383	struct xfs_perag	*pag,
2384	struct xfs_trans	*tp,
2385	xfs_ino_t		ino,	/* inode to locate */
2386	struct xfs_imap		*imap,	/* location map structure */
2387	uint			flags)	/* flags for inode btree lookup */
2388{
2389	struct xfs_mount	*mp = pag->pag_mount;
2390	xfs_agblock_t		agbno;	/* block number of inode in the alloc group */
2391	xfs_agino_t		agino;	/* inode number within alloc group */
2392	xfs_agblock_t		chunk_agbno;	/* first block in inode chunk */
2393	xfs_agblock_t		cluster_agbno;	/* first block in inode cluster */
2394	int			error;	/* error code */
2395	int			offset;	/* index of inode in its buffer */
2396	xfs_agblock_t		offset_agbno;	/* blks from chunk start to inode */
 
2397
2398	ASSERT(ino != NULLFSINO);
2399
2400	/*
2401	 * Split up the inode number into its parts.
2402	 */
 
2403	agino = XFS_INO_TO_AGINO(mp, ino);
2404	agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2405	if (agbno >= mp->m_sb.sb_agblocks ||
2406	    ino != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino)) {
2407		error = -EINVAL;
2408#ifdef DEBUG
2409		/*
2410		 * Don't output diagnostic information for untrusted inodes
2411		 * as they can be invalid without implying corruption.
2412		 */
2413		if (flags & XFS_IGET_UNTRUSTED)
2414			return error;
 
 
 
 
 
 
2415		if (agbno >= mp->m_sb.sb_agblocks) {
2416			xfs_alert(mp,
2417		"%s: agbno (0x%llx) >= mp->m_sb.sb_agblocks (0x%lx)",
2418				__func__, (unsigned long long)agbno,
2419				(unsigned long)mp->m_sb.sb_agblocks);
2420		}
2421		if (ino != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino)) {
2422			xfs_alert(mp,
2423		"%s: ino (0x%llx) != XFS_AGINO_TO_INO() (0x%llx)",
2424				__func__, ino,
2425				XFS_AGINO_TO_INO(mp, pag->pag_agno, agino));
2426		}
2427		xfs_stack_trace();
2428#endif /* DEBUG */
2429		return error;
2430	}
2431
2432	/*
2433	 * For bulkstat and handle lookups, we have an untrusted inode number
2434	 * that we have to verify is valid. We cannot do this just by reading
2435	 * the inode buffer as it may have been unlinked and removed leaving
2436	 * inodes in stale state on disk. Hence we have to do a btree lookup
2437	 * in all cases where an untrusted inode number is passed.
2438	 */
2439	if (flags & XFS_IGET_UNTRUSTED) {
2440		error = xfs_imap_lookup(pag, tp, agino, agbno,
2441					&chunk_agbno, &offset_agbno, flags);
2442		if (error)
2443			return error;
2444		goto out_map;
2445	}
2446
2447	/*
2448	 * If the inode cluster size is the same as the blocksize or
2449	 * smaller we get to the buffer by simple arithmetics.
2450	 */
2451	if (M_IGEO(mp)->blocks_per_cluster == 1) {
2452		offset = XFS_INO_TO_OFFSET(mp, ino);
2453		ASSERT(offset < mp->m_sb.sb_inopblock);
2454
2455		imap->im_blkno = XFS_AGB_TO_DADDR(mp, pag->pag_agno, agbno);
2456		imap->im_len = XFS_FSB_TO_BB(mp, 1);
2457		imap->im_boffset = (unsigned short)(offset <<
2458							mp->m_sb.sb_inodelog);
2459		return 0;
 
2460	}
2461
2462	/*
2463	 * If the inode chunks are aligned then use simple maths to
2464	 * find the location. Otherwise we have to do a btree
2465	 * lookup to find the location.
2466	 */
2467	if (M_IGEO(mp)->inoalign_mask) {
2468		offset_agbno = agbno & M_IGEO(mp)->inoalign_mask;
2469		chunk_agbno = agbno - offset_agbno;
2470	} else {
2471		error = xfs_imap_lookup(pag, tp, agino, agbno,
2472					&chunk_agbno, &offset_agbno, flags);
2473		if (error)
2474			return error;
2475	}
2476
2477out_map:
2478	ASSERT(agbno >= chunk_agbno);
2479	cluster_agbno = chunk_agbno +
2480		((offset_agbno / M_IGEO(mp)->blocks_per_cluster) *
2481		 M_IGEO(mp)->blocks_per_cluster);
2482	offset = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) +
2483		XFS_INO_TO_OFFSET(mp, ino);
2484
2485	imap->im_blkno = XFS_AGB_TO_DADDR(mp, pag->pag_agno, cluster_agbno);
2486	imap->im_len = XFS_FSB_TO_BB(mp, M_IGEO(mp)->blocks_per_cluster);
2487	imap->im_boffset = (unsigned short)(offset << mp->m_sb.sb_inodelog);
2488
2489	/*
2490	 * If the inode number maps to a block outside the bounds
2491	 * of the file system then return NULL rather than calling
2492	 * read_buf and panicing when we get an error from the
2493	 * driver.
2494	 */
2495	if ((imap->im_blkno + imap->im_len) >
2496	    XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
2497		xfs_alert(mp,
2498	"%s: (im_blkno (0x%llx) + im_len (0x%llx)) > sb_dblocks (0x%llx)",
2499			__func__, (unsigned long long) imap->im_blkno,
2500			(unsigned long long) imap->im_len,
2501			XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
2502		return -EINVAL;
 
2503	}
2504	return 0;
 
 
 
 
2505}
2506
2507/*
2508 * Log specified fields for the ag hdr (inode section). The growth of the agi
2509 * structure over time requires that we interpret the buffer as two logical
2510 * regions delineated by the end of the unlinked list. This is due to the size
2511 * of the hash table and its location in the middle of the agi.
2512 *
2513 * For example, a request to log a field before agi_unlinked and a field after
2514 * agi_unlinked could cause us to log the entire hash table and use an excessive
2515 * amount of log space. To avoid this behavior, log the region up through
2516 * agi_unlinked in one call and the region after agi_unlinked through the end of
2517 * the structure in another.
2518 */
2519void
2520xfs_ialloc_log_agi(
2521	struct xfs_trans	*tp,
2522	struct xfs_buf		*bp,
2523	uint32_t		fields)
2524{
2525	int			first;		/* first byte number */
2526	int			last;		/* last byte number */
2527	static const short	offsets[] = {	/* field starting offsets */
2528					/* keep in sync with bit definitions */
2529		offsetof(xfs_agi_t, agi_magicnum),
2530		offsetof(xfs_agi_t, agi_versionnum),
2531		offsetof(xfs_agi_t, agi_seqno),
2532		offsetof(xfs_agi_t, agi_length),
2533		offsetof(xfs_agi_t, agi_count),
2534		offsetof(xfs_agi_t, agi_root),
2535		offsetof(xfs_agi_t, agi_level),
2536		offsetof(xfs_agi_t, agi_freecount),
2537		offsetof(xfs_agi_t, agi_newino),
2538		offsetof(xfs_agi_t, agi_dirino),
2539		offsetof(xfs_agi_t, agi_unlinked),
2540		offsetof(xfs_agi_t, agi_free_root),
2541		offsetof(xfs_agi_t, agi_free_level),
2542		offsetof(xfs_agi_t, agi_iblocks),
2543		sizeof(xfs_agi_t)
2544	};
2545#ifdef DEBUG
2546	struct xfs_agi		*agi = bp->b_addr;
2547
2548	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
2549#endif
2550
2551	/*
2552	 * Compute byte offsets for the first and last fields in the first
2553	 * region and log the agi buffer. This only logs up through
2554	 * agi_unlinked.
2555	 */
2556	if (fields & XFS_AGI_ALL_BITS_R1) {
2557		xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R1,
2558				  &first, &last);
2559		xfs_trans_log_buf(tp, bp, first, last);
2560	}
2561
2562	/*
2563	 * Mask off the bits in the first region and calculate the first and
2564	 * last field offsets for any bits in the second region.
2565	 */
2566	fields &= ~XFS_AGI_ALL_BITS_R1;
2567	if (fields) {
2568		xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R2,
2569				  &first, &last);
2570		xfs_trans_log_buf(tp, bp, first, last);
2571	}
2572}
2573
2574static xfs_failaddr_t
2575xfs_agi_verify(
2576	struct xfs_buf		*bp)
2577{
2578	struct xfs_mount	*mp = bp->b_mount;
2579	struct xfs_agi		*agi = bp->b_addr;
2580	xfs_failaddr_t		fa;
2581	uint32_t		agi_seqno = be32_to_cpu(agi->agi_seqno);
2582	uint32_t		agi_length = be32_to_cpu(agi->agi_length);
2583	int			i;
2584
2585	if (xfs_has_crc(mp)) {
2586		if (!uuid_equal(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid))
2587			return __this_address;
2588		if (!xfs_log_check_lsn(mp, be64_to_cpu(agi->agi_lsn)))
2589			return __this_address;
2590	}
2591
2592	/*
2593	 * Validate the magic number of the agi block.
2594	 */
2595	if (!xfs_verify_magic(bp, agi->agi_magicnum))
2596		return __this_address;
2597	if (!XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)))
2598		return __this_address;
2599
2600	fa = xfs_validate_ag_length(bp, agi_seqno, agi_length);
2601	if (fa)
2602		return fa;
2603
2604	if (be32_to_cpu(agi->agi_level) < 1 ||
2605	    be32_to_cpu(agi->agi_level) > M_IGEO(mp)->inobt_maxlevels)
2606		return __this_address;
2607
2608	if (xfs_has_finobt(mp) &&
2609	    (be32_to_cpu(agi->agi_free_level) < 1 ||
2610	     be32_to_cpu(agi->agi_free_level) > M_IGEO(mp)->inobt_maxlevels))
2611		return __this_address;
2612
 
 
 
 
 
 
 
 
 
2613	for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++) {
2614		if (agi->agi_unlinked[i] == cpu_to_be32(NULLAGINO))
2615			continue;
2616		if (!xfs_verify_ino(mp, be32_to_cpu(agi->agi_unlinked[i])))
2617			return __this_address;
2618	}
2619
2620	return NULL;
2621}
2622
2623static void
2624xfs_agi_read_verify(
2625	struct xfs_buf	*bp)
2626{
2627	struct xfs_mount *mp = bp->b_mount;
2628	xfs_failaddr_t	fa;
2629
2630	if (xfs_has_crc(mp) &&
2631	    !xfs_buf_verify_cksum(bp, XFS_AGI_CRC_OFF))
2632		xfs_verifier_error(bp, -EFSBADCRC, __this_address);
2633	else {
2634		fa = xfs_agi_verify(bp);
2635		if (XFS_TEST_ERROR(fa, mp, XFS_ERRTAG_IALLOC_READ_AGI))
2636			xfs_verifier_error(bp, -EFSCORRUPTED, fa);
2637	}
2638}
2639
2640static void
2641xfs_agi_write_verify(
2642	struct xfs_buf	*bp)
2643{
2644	struct xfs_mount	*mp = bp->b_mount;
2645	struct xfs_buf_log_item	*bip = bp->b_log_item;
2646	struct xfs_agi		*agi = bp->b_addr;
2647	xfs_failaddr_t		fa;
2648
2649	fa = xfs_agi_verify(bp);
2650	if (fa) {
2651		xfs_verifier_error(bp, -EFSCORRUPTED, fa);
2652		return;
2653	}
2654
2655	if (!xfs_has_crc(mp))
2656		return;
2657
2658	if (bip)
2659		agi->agi_lsn = cpu_to_be64(bip->bli_item.li_lsn);
2660	xfs_buf_update_cksum(bp, XFS_AGI_CRC_OFF);
2661}
2662
2663const struct xfs_buf_ops xfs_agi_buf_ops = {
2664	.name = "xfs_agi",
2665	.magic = { cpu_to_be32(XFS_AGI_MAGIC), cpu_to_be32(XFS_AGI_MAGIC) },
2666	.verify_read = xfs_agi_read_verify,
2667	.verify_write = xfs_agi_write_verify,
2668	.verify_struct = xfs_agi_verify,
2669};
2670
2671/*
2672 * Read in the allocation group header (inode allocation section)
2673 */
2674int
2675xfs_read_agi(
2676	struct xfs_perag	*pag,
2677	struct xfs_trans	*tp,
2678	struct xfs_buf		**agibpp)
2679{
2680	struct xfs_mount	*mp = pag->pag_mount;
2681	int			error;
2682
2683	trace_xfs_read_agi(pag->pag_mount, pag->pag_agno);
2684
2685	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
2686			XFS_AG_DADDR(mp, pag->pag_agno, XFS_AGI_DADDR(mp)),
2687			XFS_FSS_TO_BB(mp, 1), 0, agibpp, &xfs_agi_buf_ops);
2688	if (xfs_metadata_is_sick(error))
2689		xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
2690	if (error)
2691		return error;
2692	if (tp)
2693		xfs_trans_buf_set_type(tp, *agibpp, XFS_BLFT_AGI_BUF);
2694
2695	xfs_buf_set_ref(*agibpp, XFS_AGI_REF);
2696	return 0;
2697}
2698
2699/*
2700 * Read in the agi and initialise the per-ag data. If the caller supplies a
2701 * @agibpp, return the locked AGI buffer to them, otherwise release it.
2702 */
2703int
2704xfs_ialloc_read_agi(
2705	struct xfs_perag	*pag,
2706	struct xfs_trans	*tp,
2707	struct xfs_buf		**agibpp)
2708{
2709	struct xfs_buf		*agibp;
2710	struct xfs_agi		*agi;
2711	int			error;
2712
2713	trace_xfs_ialloc_read_agi(pag->pag_mount, pag->pag_agno);
2714
2715	error = xfs_read_agi(pag, tp, &agibp);
2716	if (error)
2717		return error;
2718
2719	agi = agibp->b_addr;
2720	if (!xfs_perag_initialised_agi(pag)) {
2721		pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);
2722		pag->pagi_count = be32_to_cpu(agi->agi_count);
2723		set_bit(XFS_AGSTATE_AGI_INIT, &pag->pag_opstate);
2724	}
2725
2726	/*
2727	 * It's possible for these to be out of sync if
2728	 * we are in the middle of a forced shutdown.
2729	 */
2730	ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
2731		xfs_is_shutdown(pag->pag_mount));
2732	if (agibpp)
2733		*agibpp = agibp;
2734	else
2735		xfs_trans_brelse(tp, agibp);
2736	return 0;
2737}
2738
2739/* How many inodes are backed by inode clusters ondisk? */
2740STATIC int
2741xfs_ialloc_count_ondisk(
2742	struct xfs_btree_cur		*cur,
2743	xfs_agino_t			low,
2744	xfs_agino_t			high,
2745	unsigned int			*allocated)
2746{
2747	struct xfs_inobt_rec_incore	irec;
2748	unsigned int			ret = 0;
2749	int				has_record;
2750	int				error;
 
 
2751
 
2752	error = xfs_inobt_lookup(cur, low, XFS_LOOKUP_LE, &has_record);
2753	if (error)
2754		return error;
2755
2756	while (has_record) {
2757		unsigned int		i, hole_idx;
2758
2759		error = xfs_inobt_get_rec(cur, &irec, &has_record);
2760		if (error)
2761			return error;
2762		if (irec.ir_startino > high)
2763			break;
2764
2765		for (i = 0; i < XFS_INODES_PER_CHUNK; i++) {
2766			if (irec.ir_startino + i < low)
 
 
 
2767				continue;
2768			if (irec.ir_startino + i > high)
2769				break;
2770
2771			hole_idx = i / XFS_INODES_PER_HOLEMASK_BIT;
2772			if (!(irec.ir_holemask & (1U << hole_idx)))
2773				ret++;
2774		}
2775
2776		error = xfs_btree_increment(cur, 0, &has_record);
2777		if (error)
2778			return error;
2779	}
2780
2781	*allocated = ret;
2782	return 0;
2783}
2784
2785/* Is there an inode record covering a given extent? */
2786int
2787xfs_ialloc_has_inodes_at_extent(
2788	struct xfs_btree_cur	*cur,
2789	xfs_agblock_t		bno,
2790	xfs_extlen_t		len,
2791	enum xbtree_recpacking	*outcome)
2792{
2793	xfs_agino_t		agino;
2794	xfs_agino_t		last_agino;
2795	unsigned int		allocated;
2796	int			error;
2797
2798	agino = XFS_AGB_TO_AGINO(cur->bc_mp, bno);
2799	last_agino = XFS_AGB_TO_AGINO(cur->bc_mp, bno + len) - 1;
2800
2801	error = xfs_ialloc_count_ondisk(cur, agino, last_agino, &allocated);
2802	if (error)
2803		return error;
2804
2805	if (allocated == 0)
2806		*outcome = XBTREE_RECPACKING_EMPTY;
2807	else if (allocated == last_agino - agino + 1)
2808		*outcome = XBTREE_RECPACKING_FULL;
2809	else
2810		*outcome = XBTREE_RECPACKING_SPARSE;
2811	return 0;
2812}
2813
2814struct xfs_ialloc_count_inodes {
2815	xfs_agino_t			count;
2816	xfs_agino_t			freecount;
2817};
2818
2819/* Record inode counts across all inobt records. */
2820STATIC int
2821xfs_ialloc_count_inodes_rec(
2822	struct xfs_btree_cur		*cur,
2823	const union xfs_btree_rec	*rec,
2824	void				*priv)
2825{
2826	struct xfs_inobt_rec_incore	irec;
2827	struct xfs_ialloc_count_inodes	*ci = priv;
2828	xfs_failaddr_t			fa;
2829
2830	xfs_inobt_btrec_to_irec(cur->bc_mp, rec, &irec);
2831	fa = xfs_inobt_check_irec(cur->bc_ag.pag, &irec);
2832	if (fa)
2833		return xfs_inobt_complain_bad_rec(cur, fa, &irec);
2834
2835	ci->count += irec.ir_count;
2836	ci->freecount += irec.ir_freecount;
2837
2838	return 0;
2839}
2840
2841/* Count allocated and free inodes under an inobt. */
2842int
2843xfs_ialloc_count_inodes(
2844	struct xfs_btree_cur		*cur,
2845	xfs_agino_t			*count,
2846	xfs_agino_t			*freecount)
2847{
2848	struct xfs_ialloc_count_inodes	ci = {0};
2849	int				error;
2850
2851	ASSERT(xfs_btree_is_ino(cur->bc_ops));
2852	error = xfs_btree_query_all(cur, xfs_ialloc_count_inodes_rec, &ci);
2853	if (error)
2854		return error;
2855
2856	*count = ci.count;
2857	*freecount = ci.freecount;
2858	return 0;
2859}
2860
2861/*
2862 * Initialize inode-related geometry information.
2863 *
2864 * Compute the inode btree min and max levels and set maxicount.
2865 *
2866 * Set the inode cluster size.  This may still be overridden by the file
2867 * system block size if it is larger than the chosen cluster size.
2868 *
2869 * For v5 filesystems, scale the cluster size with the inode size to keep a
2870 * constant ratio of inode per cluster buffer, but only if mkfs has set the
2871 * inode alignment value appropriately for larger cluster sizes.
2872 *
2873 * Then compute the inode cluster alignment information.
2874 */
2875void
2876xfs_ialloc_setup_geometry(
2877	struct xfs_mount	*mp)
2878{
2879	struct xfs_sb		*sbp = &mp->m_sb;
2880	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2881	uint64_t		icount;
2882	uint			inodes;
2883
2884	igeo->new_diflags2 = 0;
2885	if (xfs_has_bigtime(mp))
2886		igeo->new_diflags2 |= XFS_DIFLAG2_BIGTIME;
2887	if (xfs_has_large_extent_counts(mp))
2888		igeo->new_diflags2 |= XFS_DIFLAG2_NREXT64;
2889
2890	/* Compute inode btree geometry. */
2891	igeo->agino_log = sbp->sb_inopblog + sbp->sb_agblklog;
2892	igeo->inobt_mxr[0] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 1);
2893	igeo->inobt_mxr[1] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 0);
2894	igeo->inobt_mnr[0] = igeo->inobt_mxr[0] / 2;
2895	igeo->inobt_mnr[1] = igeo->inobt_mxr[1] / 2;
2896
2897	igeo->ialloc_inos = max_t(uint16_t, XFS_INODES_PER_CHUNK,
2898			sbp->sb_inopblock);
2899	igeo->ialloc_blks = igeo->ialloc_inos >> sbp->sb_inopblog;
2900
2901	if (sbp->sb_spino_align)
2902		igeo->ialloc_min_blks = sbp->sb_spino_align;
2903	else
2904		igeo->ialloc_min_blks = igeo->ialloc_blks;
2905
2906	/* Compute and fill in value of m_ino_geo.inobt_maxlevels. */
2907	inodes = (1LL << XFS_INO_AGINO_BITS(mp)) >> XFS_INODES_PER_CHUNK_LOG;
2908	igeo->inobt_maxlevels = xfs_btree_compute_maxlevels(igeo->inobt_mnr,
2909			inodes);
2910	ASSERT(igeo->inobt_maxlevels <= xfs_iallocbt_maxlevels_ondisk());
2911
2912	/*
2913	 * Set the maximum inode count for this filesystem, being careful not
2914	 * to use obviously garbage sb_inopblog/sb_inopblock values.  Regular
2915	 * users should never get here due to failing sb verification, but
2916	 * certain users (xfs_db) need to be usable even with corrupt metadata.
2917	 */
2918	if (sbp->sb_imax_pct && igeo->ialloc_blks) {
2919		/*
2920		 * Make sure the maximum inode count is a multiple
2921		 * of the units we allocate inodes in.
2922		 */
2923		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
2924		do_div(icount, 100);
2925		do_div(icount, igeo->ialloc_blks);
2926		igeo->maxicount = XFS_FSB_TO_INO(mp,
2927				icount * igeo->ialloc_blks);
2928	} else {
2929		igeo->maxicount = 0;
2930	}
2931
2932	/*
2933	 * Compute the desired size of an inode cluster buffer size, which
2934	 * starts at 8K and (on v5 filesystems) scales up with larger inode
2935	 * sizes.
2936	 *
2937	 * Preserve the desired inode cluster size because the sparse inodes
2938	 * feature uses that desired size (not the actual size) to compute the
2939	 * sparse inode alignment.  The mount code validates this value, so we
2940	 * cannot change the behavior.
2941	 */
2942	igeo->inode_cluster_size_raw = XFS_INODE_BIG_CLUSTER_SIZE;
2943	if (xfs_has_v3inodes(mp)) {
2944		int	new_size = igeo->inode_cluster_size_raw;
2945
2946		new_size *= mp->m_sb.sb_inodesize / XFS_DINODE_MIN_SIZE;
2947		if (mp->m_sb.sb_inoalignmt >= XFS_B_TO_FSBT(mp, new_size))
2948			igeo->inode_cluster_size_raw = new_size;
2949	}
2950
2951	/* Calculate inode cluster ratios. */
2952	if (igeo->inode_cluster_size_raw > mp->m_sb.sb_blocksize)
2953		igeo->blocks_per_cluster = XFS_B_TO_FSBT(mp,
2954				igeo->inode_cluster_size_raw);
2955	else
2956		igeo->blocks_per_cluster = 1;
2957	igeo->inode_cluster_size = XFS_FSB_TO_B(mp, igeo->blocks_per_cluster);
2958	igeo->inodes_per_cluster = XFS_FSB_TO_INO(mp, igeo->blocks_per_cluster);
2959
2960	/* Calculate inode cluster alignment. */
2961	if (xfs_has_align(mp) &&
2962	    mp->m_sb.sb_inoalignmt >= igeo->blocks_per_cluster)
2963		igeo->cluster_align = mp->m_sb.sb_inoalignmt;
2964	else
2965		igeo->cluster_align = 1;
2966	igeo->inoalign_mask = igeo->cluster_align - 1;
2967	igeo->cluster_align_inodes = XFS_FSB_TO_INO(mp, igeo->cluster_align);
2968
2969	/*
2970	 * If we are using stripe alignment, check whether
2971	 * the stripe unit is a multiple of the inode alignment
2972	 */
2973	if (mp->m_dalign && igeo->inoalign_mask &&
2974	    !(mp->m_dalign & igeo->inoalign_mask))
2975		igeo->ialloc_align = mp->m_dalign;
2976	else
2977		igeo->ialloc_align = 0;
2978}
2979
2980/* Compute the location of the root directory inode that is laid out by mkfs. */
2981xfs_ino_t
2982xfs_ialloc_calc_rootino(
2983	struct xfs_mount	*mp,
2984	int			sunit)
2985{
2986	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2987	xfs_agblock_t		first_bno;
2988
2989	/*
2990	 * Pre-calculate the geometry of AG 0.  We know what it looks like
2991	 * because libxfs knows how to create allocation groups now.
2992	 *
2993	 * first_bno is the first block in which mkfs could possibly have
2994	 * allocated the root directory inode, once we factor in the metadata
2995	 * that mkfs formats before it.  Namely, the four AG headers...
2996	 */
2997	first_bno = howmany(4 * mp->m_sb.sb_sectsize, mp->m_sb.sb_blocksize);
2998
2999	/* ...the two free space btree roots... */
3000	first_bno += 2;
3001
3002	/* ...the inode btree root... */
3003	first_bno += 1;
3004
3005	/* ...the initial AGFL... */
3006	first_bno += xfs_alloc_min_freelist(mp, NULL);
3007
3008	/* ...the free inode btree root... */
3009	if (xfs_has_finobt(mp))
3010		first_bno++;
3011
3012	/* ...the reverse mapping btree root... */
3013	if (xfs_has_rmapbt(mp))
3014		first_bno++;
3015
3016	/* ...the reference count btree... */
3017	if (xfs_has_reflink(mp))
3018		first_bno++;
3019
3020	/*
3021	 * ...and the log, if it is allocated in the first allocation group.
3022	 *
3023	 * This can happen with filesystems that only have a single
3024	 * allocation group, or very odd geometries created by old mkfs
3025	 * versions on very small filesystems.
3026	 */
3027	if (xfs_ag_contains_log(mp, 0))
3028		 first_bno += mp->m_sb.sb_logblocks;
3029
3030	/*
3031	 * Now round first_bno up to whatever allocation alignment is given
3032	 * by the filesystem or was passed in.
3033	 */
3034	if (xfs_has_dalign(mp) && igeo->ialloc_align > 0)
3035		first_bno = roundup(first_bno, sunit);
3036	else if (xfs_has_align(mp) &&
3037			mp->m_sb.sb_inoalignmt > 1)
3038		first_bno = roundup(first_bno, mp->m_sb.sb_inoalignmt);
3039
3040	return XFS_AGINO_TO_INO(mp, 0, XFS_AGB_TO_AGINO(mp, first_bno));
3041}
3042
3043/*
3044 * Ensure there are not sparse inode clusters that cross the new EOAG.
3045 *
3046 * This is a no-op for non-spinode filesystems since clusters are always fully
3047 * allocated and checking the bnobt suffices.  However, a spinode filesystem
3048 * could have a record where the upper inodes are free blocks.  If those blocks
3049 * were removed from the filesystem, the inode record would extend beyond EOAG,
3050 * which will be flagged as corruption.
3051 */
3052int
3053xfs_ialloc_check_shrink(
3054	struct xfs_perag	*pag,
3055	struct xfs_trans	*tp,
 
3056	struct xfs_buf		*agibp,
3057	xfs_agblock_t		new_length)
3058{
3059	struct xfs_inobt_rec_incore rec;
3060	struct xfs_btree_cur	*cur;
3061	xfs_agino_t		agino;
 
 
3062	int			has;
3063	int			error;
3064
3065	if (!xfs_has_sparseinodes(pag->pag_mount))
3066		return 0;
3067
3068	cur = xfs_inobt_init_cursor(pag, tp, agibp);
 
3069
3070	/* Look up the inobt record that would correspond to the new EOFS. */
3071	agino = XFS_AGB_TO_AGINO(pag->pag_mount, new_length);
3072	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &has);
3073	if (error || !has)
3074		goto out;
3075
3076	error = xfs_inobt_get_rec(cur, &rec, &has);
3077	if (error)
3078		goto out;
3079
3080	if (!has) {
3081		xfs_ag_mark_sick(pag, XFS_SICK_AG_INOBT);
3082		error = -EFSCORRUPTED;
3083		goto out;
3084	}
3085
3086	/* If the record covers inodes that would be beyond EOFS, bail out. */
3087	if (rec.ir_startino + XFS_INODES_PER_CHUNK > agino) {
3088		error = -ENOSPC;
3089		goto out;
3090	}
3091out:
3092	xfs_btree_del_cursor(cur, error);
 
3093	return error;
3094}