1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2000-2005 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_sb.h"
  14#include "xfs_mount.h"
  15#include "xfs_inode.h"
  16#include "xfs_dir2.h"
  17#include "xfs_ialloc.h"
  18#include "xfs_alloc.h"
  19#include "xfs_rtalloc.h"
  20#include "xfs_bmap.h"
  21#include "xfs_trans.h"
  22#include "xfs_trans_priv.h"
  23#include "xfs_log.h"
  24#include "xfs_log_priv.h"
  25#include "xfs_error.h"
  26#include "xfs_quota.h"
  27#include "xfs_fsops.h"
  28#include "xfs_icache.h"
  29#include "xfs_sysfs.h"
  30#include "xfs_rmap_btree.h"
  31#include "xfs_refcount_btree.h"
  32#include "xfs_reflink.h"
  33#include "xfs_extent_busy.h"
  34#include "xfs_health.h"
  35#include "xfs_trace.h"
  36#include "xfs_ag.h"
  37#include "xfs_rtbitmap.h"
  38#include "xfs_metafile.h"
  39#include "xfs_rtgroup.h"
  40#include "scrub/stats.h"
  41
  42static DEFINE_MUTEX(xfs_uuid_table_mutex);
  43static int xfs_uuid_table_size;
  44static uuid_t *xfs_uuid_table;
  45
  46void
  47xfs_uuid_table_free(void)
  48{
  49	if (xfs_uuid_table_size == 0)
  50		return;
  51	kfree(xfs_uuid_table);
  52	xfs_uuid_table = NULL;
  53	xfs_uuid_table_size = 0;
  54}
  55
  56/*
  57 * See if the UUID is unique among mounted XFS filesystems.
  58 * Mount fails if UUID is nil or a FS with the same UUID is already mounted.
  59 */
  60STATIC int
  61xfs_uuid_mount(
  62	struct xfs_mount	*mp)
  63{
  64	uuid_t			*uuid = &mp->m_sb.sb_uuid;
  65	int			hole, i;
  66
  67	/* Publish UUID in struct super_block */
  68	super_set_uuid(mp->m_super, uuid->b, sizeof(*uuid));
  69
  70	if (xfs_has_nouuid(mp))
  71		return 0;
  72
  73	if (uuid_is_null(uuid)) {
  74		xfs_warn(mp, "Filesystem has null UUID - can't mount");
  75		return -EINVAL;
  76	}
  77
  78	mutex_lock(&xfs_uuid_table_mutex);
  79	for (i = 0, hole = -1; i < xfs_uuid_table_size; i++) {
  80		if (uuid_is_null(&xfs_uuid_table[i])) {
  81			hole = i;
  82			continue;
  83		}
  84		if (uuid_equal(uuid, &xfs_uuid_table[i]))
  85			goto out_duplicate;
  86	}
  87
  88	if (hole < 0) {
  89		xfs_uuid_table = krealloc(xfs_uuid_table,
  90			(xfs_uuid_table_size + 1) * sizeof(*xfs_uuid_table),
  91			GFP_KERNEL | __GFP_NOFAIL);
  92		hole = xfs_uuid_table_size++;
  93	}
  94	xfs_uuid_table[hole] = *uuid;
  95	mutex_unlock(&xfs_uuid_table_mutex);
  96
  97	return 0;
  98
  99 out_duplicate:
 100	mutex_unlock(&xfs_uuid_table_mutex);
 101	xfs_warn(mp, "Filesystem has duplicate UUID %pU - can't mount", uuid);
 102	return -EINVAL;
 103}
 104
 105STATIC void
 106xfs_uuid_unmount(
 107	struct xfs_mount	*mp)
 108{
 109	uuid_t			*uuid = &mp->m_sb.sb_uuid;
 110	int			i;
 111
 112	if (xfs_has_nouuid(mp))
 113		return;
 114
 115	mutex_lock(&xfs_uuid_table_mutex);
 116	for (i = 0; i < xfs_uuid_table_size; i++) {
 117		if (uuid_is_null(&xfs_uuid_table[i]))
 118			continue;
 119		if (!uuid_equal(uuid, &xfs_uuid_table[i]))
 120			continue;
 121		memset(&xfs_uuid_table[i], 0, sizeof(uuid_t));
 122		break;
 123	}
 124	ASSERT(i < xfs_uuid_table_size);
 125	mutex_unlock(&xfs_uuid_table_mutex);
 126}
 127
 128/*
 129 * Check size of device based on the (data/realtime) block count.
 130 * Note: this check is used by the growfs code as well as mount.
 131 */
 132int
 133xfs_sb_validate_fsb_count(
 134	xfs_sb_t	*sbp,
 135	uint64_t	nblocks)
 136{
 137	uint64_t		max_bytes;
 138
 139	ASSERT(sbp->sb_blocklog >= BBSHIFT);
 140
 141	if (check_shl_overflow(nblocks, sbp->sb_blocklog, &max_bytes))
 142		return -EFBIG;
 143
 144	/* Limited by ULONG_MAX of page cache index */
 145	if (max_bytes >> PAGE_SHIFT > ULONG_MAX)
 146		return -EFBIG;
 147	return 0;
 148}
 149
 150/*
 151 * xfs_readsb
 152 *
 153 * Does the initial read of the superblock.
 154 */
 155int
 156xfs_readsb(
 157	struct xfs_mount *mp,
 158	int		flags)
 159{
 160	unsigned int	sector_size;
 161	struct xfs_buf	*bp;
 162	struct xfs_sb	*sbp = &mp->m_sb;
 163	int		error;
 164	int		loud = !(flags & XFS_MFSI_QUIET);
 165	const struct xfs_buf_ops *buf_ops;
 166
 167	ASSERT(mp->m_sb_bp == NULL);
 168	ASSERT(mp->m_ddev_targp != NULL);
 169
 170	/*
 171	 * For the initial read, we must guess at the sector
 172	 * size based on the block device.  It's enough to
 173	 * get the sb_sectsize out of the superblock and
 174	 * then reread with the proper length.
 175	 * We don't verify it yet, because it may not be complete.
 176	 */
 177	sector_size = xfs_getsize_buftarg(mp->m_ddev_targp);
 178	buf_ops = NULL;
 179
 180	/*
 181	 * Allocate a (locked) buffer to hold the superblock. This will be kept
 182	 * around at all times to optimize access to the superblock. Therefore,
 183	 * set XBF_NO_IOACCT to make sure it doesn't hold the buftarg count
 184	 * elevated.
 185	 */
 186reread:
 187	error = xfs_buf_read_uncached(mp->m_ddev_targp, XFS_SB_DADDR,
 188				      BTOBB(sector_size), XBF_NO_IOACCT, &bp,
 189				      buf_ops);
 190	if (error) {
 191		if (loud)
 192			xfs_warn(mp, "SB validate failed with error %d.", error);
 193		/* bad CRC means corrupted metadata */
 194		if (error == -EFSBADCRC)
 195			error = -EFSCORRUPTED;
 196		return error;
 197	}
 198
 199	/*
 200	 * Initialize the mount structure from the superblock.
 201	 */
 202	xfs_sb_from_disk(sbp, bp->b_addr);
 203
 204	/*
 205	 * If we haven't validated the superblock, do so now before we try
 206	 * to check the sector size and reread the superblock appropriately.
 207	 */
 208	if (sbp->sb_magicnum != XFS_SB_MAGIC) {
 209		if (loud)
 210			xfs_warn(mp, "Invalid superblock magic number");
 211		error = -EINVAL;
 212		goto release_buf;
 213	}
 214
 215	/*
 216	 * We must be able to do sector-sized and sector-aligned IO.
 217	 */
 218	if (sector_size > sbp->sb_sectsize) {
 219		if (loud)
 220			xfs_warn(mp, "device supports %u byte sectors (not %u)",
 221				sector_size, sbp->sb_sectsize);
 222		error = -ENOSYS;
 223		goto release_buf;
 224	}
 225
 226	if (buf_ops == NULL) {
 227		/*
 228		 * Re-read the superblock so the buffer is correctly sized,
 229		 * and properly verified.
 230		 */
 231		xfs_buf_relse(bp);
 232		sector_size = sbp->sb_sectsize;
 233		buf_ops = loud ? &xfs_sb_buf_ops : &xfs_sb_quiet_buf_ops;
 234		goto reread;
 235	}
 236
 237	mp->m_features |= xfs_sb_version_to_features(sbp);
 238	xfs_reinit_percpu_counters(mp);
 239
 240	/*
 241	 * If logged xattrs are enabled after log recovery finishes, then set
 242	 * the opstate so that log recovery will work properly.
 243	 */
 244	if (xfs_sb_version_haslogxattrs(&mp->m_sb))
 245		xfs_set_using_logged_xattrs(mp);
 246
 247	/* no need to be quiet anymore, so reset the buf ops */
 248	bp->b_ops = &xfs_sb_buf_ops;
 249
 250	mp->m_sb_bp = bp;
 251	xfs_buf_unlock(bp);
 252	return 0;
 253
 254release_buf:
 255	xfs_buf_relse(bp);
 256	return error;
 257}
 258
 259/*
 260 * If the sunit/swidth change would move the precomputed root inode value, we
 261 * must reject the ondisk change because repair will stumble over that.
 262 * However, we allow the mount to proceed because we never rejected this
 263 * combination before.  Returns true to update the sb, false otherwise.
 264 */
 265static inline int
 266xfs_check_new_dalign(
 267	struct xfs_mount	*mp,
 268	int			new_dalign,
 269	bool			*update_sb)
 270{
 271	struct xfs_sb		*sbp = &mp->m_sb;
 272	xfs_ino_t		calc_ino;
 273
 274	calc_ino = xfs_ialloc_calc_rootino(mp, new_dalign);
 275	trace_xfs_check_new_dalign(mp, new_dalign, calc_ino);
 276
 277	if (sbp->sb_rootino == calc_ino) {
 278		*update_sb = true;
 279		return 0;
 280	}
 281
 282	xfs_warn(mp,
 283"Cannot change stripe alignment; would require moving root inode.");
 284
 285	/*
 286	 * XXX: Next time we add a new incompat feature, this should start
 287	 * returning -EINVAL to fail the mount.  Until then, spit out a warning
 288	 * that we're ignoring the administrator's instructions.
 289	 */
 290	xfs_warn(mp, "Skipping superblock stripe alignment update.");
 291	*update_sb = false;
 292	return 0;
 293}
 294
 295/*
 296 * If we were provided with new sunit/swidth values as mount options, make sure
 297 * that they pass basic alignment and superblock feature checks, and convert
 298 * them into the same units (FSB) that everything else expects.  This step
 299 * /must/ be done before computing the inode geometry.
 300 */
 301STATIC int
 302xfs_validate_new_dalign(
 303	struct xfs_mount	*mp)
 304{
 305	if (mp->m_dalign == 0)
 306		return 0;
 307
 308	/*
 309	 * If stripe unit and stripe width are not multiples
 310	 * of the fs blocksize turn off alignment.
 311	 */
 312	if ((BBTOB(mp->m_dalign) & mp->m_blockmask) ||
 313	    (BBTOB(mp->m_swidth) & mp->m_blockmask)) {
 314		xfs_warn(mp,
 315	"alignment check failed: sunit/swidth vs. blocksize(%d)",
 316			mp->m_sb.sb_blocksize);
 317		return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 318	}
 319
 320	/*
 321	 * Convert the stripe unit and width to FSBs.
 322	 */
 323	mp->m_dalign = XFS_BB_TO_FSBT(mp, mp->m_dalign);
 324	if (mp->m_dalign && (mp->m_sb.sb_agblocks % mp->m_dalign)) {
 325		xfs_warn(mp,
 326	"alignment check failed: sunit/swidth vs. agsize(%d)",
 327			mp->m_sb.sb_agblocks);
 328		return -EINVAL;
 329	}
 330
 331	if (!mp->m_dalign) {
 332		xfs_warn(mp,
 333	"alignment check failed: sunit(%d) less than bsize(%d)",
 334			mp->m_dalign, mp->m_sb.sb_blocksize);
 335		return -EINVAL;
 336	}
 337
 338	mp->m_swidth = XFS_BB_TO_FSBT(mp, mp->m_swidth);
 339
 340	if (!xfs_has_dalign(mp)) {
 341		xfs_warn(mp,
 342"cannot change alignment: superblock does not support data alignment");
 343		return -EINVAL;
 344	}
 345
 346	return 0;
 347}
 348
 349/* Update alignment values based on mount options and sb values. */
 350STATIC int
 351xfs_update_alignment(
 352	struct xfs_mount	*mp)
 353{
 354	struct xfs_sb		*sbp = &mp->m_sb;
 355
 356	if (mp->m_dalign) {
 357		bool		update_sb;
 358		int		error;
 359
 360		if (sbp->sb_unit == mp->m_dalign &&
 361		    sbp->sb_width == mp->m_swidth)
 362			return 0;
 363
 364		error = xfs_check_new_dalign(mp, mp->m_dalign, &update_sb);
 365		if (error || !update_sb)
 366			return error;
 367
 368		sbp->sb_unit = mp->m_dalign;
 369		sbp->sb_width = mp->m_swidth;
 370		mp->m_update_sb = true;
 371	} else if (!xfs_has_noalign(mp) && xfs_has_dalign(mp)) {
 
 372		mp->m_dalign = sbp->sb_unit;
 373		mp->m_swidth = sbp->sb_width;
 374	}
 375
 376	return 0;
 377}
 378
 379/*
 380 * precalculate the low space thresholds for dynamic speculative preallocation.
 381 */
 382void
 383xfs_set_low_space_thresholds(
 384	struct xfs_mount	*mp)
 385{
 386	uint64_t		dblocks = mp->m_sb.sb_dblocks;
 387	uint64_t		rtexts = mp->m_sb.sb_rextents;
 388	int			i;
 389
 390	do_div(dblocks, 100);
 391	do_div(rtexts, 100);
 392
 393	for (i = 0; i < XFS_LOWSP_MAX; i++) {
 394		mp->m_low_space[i] = dblocks * (i + 1);
 395		mp->m_low_rtexts[i] = rtexts * (i + 1);
 
 
 396	}
 397}
 398
 399/*
 400 * Check that the data (and log if separate) is an ok size.
 401 */
 402STATIC int
 403xfs_check_sizes(
 404	struct xfs_mount *mp)
 405{
 406	struct xfs_buf	*bp;
 407	xfs_daddr_t	d;
 408	int		error;
 409
 410	d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks);
 411	if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_dblocks) {
 412		xfs_warn(mp, "filesystem size mismatch detected");
 413		return -EFBIG;
 414	}
 415	error = xfs_buf_read_uncached(mp->m_ddev_targp,
 416					d - XFS_FSS_TO_BB(mp, 1),
 417					XFS_FSS_TO_BB(mp, 1), 0, &bp, NULL);
 418	if (error) {
 419		xfs_warn(mp, "last sector read failed");
 420		return error;
 421	}
 422	xfs_buf_relse(bp);
 423
 424	if (mp->m_logdev_targp == mp->m_ddev_targp)
 425		return 0;
 426
 427	d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_logblocks);
 428	if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_logblocks) {
 429		xfs_warn(mp, "log size mismatch detected");
 430		return -EFBIG;
 431	}
 432	error = xfs_buf_read_uncached(mp->m_logdev_targp,
 433					d - XFS_FSB_TO_BB(mp, 1),
 434					XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
 435	if (error) {
 436		xfs_warn(mp, "log device read failed");
 437		return error;
 438	}
 439	xfs_buf_relse(bp);
 440	return 0;
 441}
 442
 443/*
 444 * Clear the quotaflags in memory and in the superblock.
 445 */
 446int
 447xfs_mount_reset_sbqflags(
 448	struct xfs_mount	*mp)
 449{
 450	mp->m_qflags = 0;
 451
 452	/* It is OK to look at sb_qflags in the mount path without m_sb_lock. */
 453	if (mp->m_sb.sb_qflags == 0)
 454		return 0;
 455	spin_lock(&mp->m_sb_lock);
 456	mp->m_sb.sb_qflags = 0;
 457	spin_unlock(&mp->m_sb_lock);
 458
 459	if (!xfs_fs_writable(mp, SB_FREEZE_WRITE))
 460		return 0;
 461
 462	return xfs_sync_sb(mp, false);
 463}
 464
 465uint64_t
 466xfs_default_resblks(xfs_mount_t *mp)
 467{
 468	uint64_t resblks;
 469
 470	/*
 471	 * We default to 5% or 8192 fsbs of space reserved, whichever is
 472	 * smaller.  This is intended to cover concurrent allocation
 473	 * transactions when we initially hit enospc. These each require a 4
 474	 * block reservation. Hence by default we cover roughly 2000 concurrent
 475	 * allocation reservations.
 476	 */
 477	resblks = mp->m_sb.sb_dblocks;
 478	do_div(resblks, 20);
 479	resblks = min_t(uint64_t, resblks, 8192);
 480	return resblks;
 481}
 482
 483/* Ensure the summary counts are correct. */
 484STATIC int
 485xfs_check_summary_counts(
 486	struct xfs_mount	*mp)
 487{
 488	int			error = 0;
 489
 490	/*
 491	 * The AG0 superblock verifier rejects in-progress filesystems,
 492	 * so we should never see the flag set this far into mounting.
 493	 */
 494	if (mp->m_sb.sb_inprogress) {
 495		xfs_err(mp, "sb_inprogress set after log recovery??");
 496		WARN_ON(1);
 497		return -EFSCORRUPTED;
 498	}
 499
 500	/*
 501	 * Now the log is mounted, we know if it was an unclean shutdown or
 502	 * not. If it was, with the first phase of recovery has completed, we
 503	 * have consistent AG blocks on disk. We have not recovered EFIs yet,
 504	 * but they are recovered transactionally in the second recovery phase
 505	 * later.
 506	 *
 507	 * If the log was clean when we mounted, we can check the summary
 508	 * counters.  If any of them are obviously incorrect, we can recompute
 509	 * them from the AGF headers in the next step.
 510	 */
 511	if (xfs_is_clean(mp) &&
 512	    (mp->m_sb.sb_fdblocks > mp->m_sb.sb_dblocks ||
 513	     !xfs_verify_icount(mp, mp->m_sb.sb_icount) ||
 514	     mp->m_sb.sb_ifree > mp->m_sb.sb_icount))
 515		xfs_fs_mark_sick(mp, XFS_SICK_FS_COUNTERS);
 516
 517	/*
 518	 * We can safely re-initialise incore superblock counters from the
 519	 * per-ag data. These may not be correct if the filesystem was not
 520	 * cleanly unmounted, so we waited for recovery to finish before doing
 521	 * this.
 522	 *
 523	 * If the filesystem was cleanly unmounted or the previous check did
 524	 * not flag anything weird, then we can trust the values in the
 525	 * superblock to be correct and we don't need to do anything here.
 526	 * Otherwise, recalculate the summary counters.
 527	 */
 528	if ((xfs_has_lazysbcount(mp) && !xfs_is_clean(mp)) ||
 529	    xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS)) {
 530		error = xfs_initialize_perag_data(mp, mp->m_sb.sb_agcount);
 531		if (error)
 532			return error;
 533	}
 534
 535	/*
 536	 * Older kernels misused sb_frextents to reflect both incore
 537	 * reservations made by running transactions and the actual count of
 538	 * free rt extents in the ondisk metadata.  Transactions committed
 539	 * during runtime can therefore contain a superblock update that
 540	 * undercounts the number of free rt extents tracked in the rt bitmap.
 541	 * A clean unmount record will have the correct frextents value since
 542	 * there can be no other transactions running at that point.
 543	 *
 544	 * If we're mounting the rt volume after recovering the log, recompute
 545	 * frextents from the rtbitmap file to fix the inconsistency.
 546	 */
 547	if (xfs_has_realtime(mp) && !xfs_is_clean(mp)) {
 548		error = xfs_rtalloc_reinit_frextents(mp);
 549		if (error)
 550			return error;
 551	}
 552
 553	return 0;
 554}
 555
 556static void
 557xfs_unmount_check(
 558	struct xfs_mount	*mp)
 559{
 560	if (xfs_is_shutdown(mp))
 561		return;
 562
 563	if (percpu_counter_sum(&mp->m_ifree) >
 564			percpu_counter_sum(&mp->m_icount)) {
 565		xfs_alert(mp, "ifree/icount mismatch at unmount");
 566		xfs_fs_mark_sick(mp, XFS_SICK_FS_COUNTERS);
 567	}
 568}
 569
 570/*
 571 * Flush and reclaim dirty inodes in preparation for unmount. Inodes and
 572 * internal inode structures can be sitting in the CIL and AIL at this point,
 573 * so we need to unpin them, write them back and/or reclaim them before unmount
 574 * can proceed.  In other words, callers are required to have inactivated all
 575 * inodes.
 576 *
 577 * An inode cluster that has been freed can have its buffer still pinned in
 578 * memory because the transaction is still sitting in a iclog. The stale inodes
 579 * on that buffer will be pinned to the buffer until the transaction hits the
 580 * disk and the callbacks run. Pushing the AIL will skip the stale inodes and
 581 * may never see the pinned buffer, so nothing will push out the iclog and
 582 * unpin the buffer.
 583 *
 584 * Hence we need to force the log to unpin everything first. However, log
 585 * forces don't wait for the discards they issue to complete, so we have to
 586 * explicitly wait for them to complete here as well.
 587 *
 588 * Then we can tell the world we are unmounting so that error handling knows
 589 * that the filesystem is going away and we should error out anything that we
 590 * have been retrying in the background.  This will prevent never-ending
 591 * retries in AIL pushing from hanging the unmount.
 592 *
 593 * Finally, we can push the AIL to clean all the remaining dirty objects, then
 594 * reclaim the remaining inodes that are still in memory at this point in time.
 595 */
 596static void
 597xfs_unmount_flush_inodes(
 598	struct xfs_mount	*mp)
 599{
 600	xfs_log_force(mp, XFS_LOG_SYNC);
 601	xfs_extent_busy_wait_all(mp);
 602	flush_workqueue(xfs_discard_wq);
 603
 604	xfs_set_unmounting(mp);
 605
 606	xfs_ail_push_all_sync(mp->m_ail);
 607	xfs_inodegc_stop(mp);
 608	cancel_delayed_work_sync(&mp->m_reclaim_work);
 609	xfs_reclaim_inodes(mp);
 610	xfs_health_unmount(mp);
 611}
 612
 613static void
 614xfs_mount_setup_inode_geom(
 615	struct xfs_mount	*mp)
 616{
 617	struct xfs_ino_geometry *igeo = M_IGEO(mp);
 618
 619	igeo->attr_fork_offset = xfs_bmap_compute_attr_offset(mp);
 620	ASSERT(igeo->attr_fork_offset < XFS_LITINO(mp));
 621
 622	xfs_ialloc_setup_geometry(mp);
 623}
 624
 625/* Mount the metadata directory tree root. */
 626STATIC int
 627xfs_mount_setup_metadir(
 628	struct xfs_mount	*mp)
 629{
 630	int			error;
 631
 632	/* Load the metadata directory root inode into memory. */
 633	error = xfs_metafile_iget(mp, mp->m_sb.sb_metadirino, XFS_METAFILE_DIR,
 634			&mp->m_metadirip);
 635	if (error)
 636		xfs_warn(mp, "Failed to load metadir root directory, error %d",
 637				error);
 638	return error;
 639}
 640
 641/* Compute maximum possible height for per-AG btree types for this fs. */
 642static inline void
 643xfs_agbtree_compute_maxlevels(
 644	struct xfs_mount	*mp)
 645{
 646	unsigned int		levels;
 647
 648	levels = max(mp->m_alloc_maxlevels, M_IGEO(mp)->inobt_maxlevels);
 649	levels = max(levels, mp->m_rmap_maxlevels);
 650	mp->m_agbtree_maxlevels = max(levels, mp->m_refc_maxlevels);
 651}
 652
 653/*
 654 * This function does the following on an initial mount of a file system:
 655 *	- reads the superblock from disk and init the mount struct
 656 *	- if we're a 32-bit kernel, do a size check on the superblock
 657 *		so we don't mount terabyte filesystems
 658 *	- init mount struct realtime fields
 659 *	- allocate inode hash table for fs
 660 *	- init directory manager
 661 *	- perform recovery and init the log manager
 662 */
 663int
 664xfs_mountfs(
 665	struct xfs_mount	*mp)
 666{
 667	struct xfs_sb		*sbp = &(mp->m_sb);
 668	struct xfs_inode	*rip;
 669	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
 
 670	uint			quotamount = 0;
 671	uint			quotaflags = 0;
 672	int			error = 0;
 673
 674	xfs_sb_mount_common(mp, sbp);
 675
 676	/*
 677	 * Check for a mismatched features2 values.  Older kernels read & wrote
 678	 * into the wrong sb offset for sb_features2 on some platforms due to
 679	 * xfs_sb_t not being 64bit size aligned when sb_features2 was added,
 680	 * which made older superblock reading/writing routines swap it as a
 681	 * 64-bit value.
 682	 *
 683	 * For backwards compatibility, we make both slots equal.
 684	 *
 685	 * If we detect a mismatched field, we OR the set bits into the existing
 686	 * features2 field in case it has already been modified; we don't want
 687	 * to lose any features.  We then update the bad location with the ORed
 688	 * value so that older kernels will see any features2 flags. The
 689	 * superblock writeback code ensures the new sb_features2 is copied to
 690	 * sb_bad_features2 before it is logged or written to disk.
 691	 */
 692	if (xfs_sb_has_mismatched_features2(sbp)) {
 693		xfs_warn(mp, "correcting sb_features alignment problem");
 694		sbp->sb_features2 |= sbp->sb_bad_features2;
 695		mp->m_update_sb = true;
 
 
 
 
 
 
 
 
 696	}
 697
 
 
 
 
 
 
 
 
 
 698
 699	/* always use v2 inodes by default now */
 700	if (!(mp->m_sb.sb_versionnum & XFS_SB_VERSION_NLINKBIT)) {
 701		mp->m_sb.sb_versionnum |= XFS_SB_VERSION_NLINKBIT;
 702		mp->m_features |= XFS_FEAT_NLINK;
 703		mp->m_update_sb = true;
 704	}
 705
 706	/*
 707	 * If we were given new sunit/swidth options, do some basic validation
 708	 * checks and convert the incore dalign and swidth values to the
 709	 * same units (FSB) that everything else uses.  This /must/ happen
 710	 * before computing the inode geometry.
 711	 */
 712	error = xfs_validate_new_dalign(mp);
 713	if (error)
 714		goto out;
 715
 716	xfs_alloc_compute_maxlevels(mp);
 717	xfs_bmap_compute_maxlevels(mp, XFS_DATA_FORK);
 718	xfs_bmap_compute_maxlevels(mp, XFS_ATTR_FORK);
 719	xfs_mount_setup_inode_geom(mp);
 720	xfs_rmapbt_compute_maxlevels(mp);
 721	xfs_refcountbt_compute_maxlevels(mp);
 722
 723	xfs_agbtree_compute_maxlevels(mp);
 724
 725	/*
 726	 * Check if sb_agblocks is aligned at stripe boundary.  If sb_agblocks
 727	 * is NOT aligned turn off m_dalign since allocator alignment is within
 728	 * an ag, therefore ag has to be aligned at stripe boundary.  Note that
 729	 * we must compute the free space and rmap btree geometry before doing
 730	 * this.
 731	 */
 732	error = xfs_update_alignment(mp);
 733	if (error)
 734		goto out;
 735
 736	/* enable fail_at_unmount as default */
 737	mp->m_fail_unmount = true;
 738
 739	super_set_sysfs_name_id(mp->m_super);
 740
 741	error = xfs_sysfs_init(&mp->m_kobj, &xfs_mp_ktype,
 742			       NULL, mp->m_super->s_id);
 743	if (error)
 744		goto out;
 745
 746	error = xfs_sysfs_init(&mp->m_stats.xs_kobj, &xfs_stats_ktype,
 747			       &mp->m_kobj, "stats");
 748	if (error)
 749		goto out_remove_sysfs;
 750
 751	xchk_stats_register(mp->m_scrub_stats, mp->m_debugfs);
 752
 753	error = xfs_error_sysfs_init(mp);
 754	if (error)
 755		goto out_remove_scrub_stats;
 756
 757	error = xfs_errortag_init(mp);
 758	if (error)
 759		goto out_remove_error_sysfs;
 760
 761	error = xfs_uuid_mount(mp);
 762	if (error)
 763		goto out_remove_errortag;
 764
 765	/*
 766	 * Update the preferred write size based on the information from the
 767	 * on-disk superblock.
 768	 */
 769	mp->m_allocsize_log =
 770		max_t(uint32_t, sbp->sb_blocklog, mp->m_allocsize_log);
 771	mp->m_allocsize_blocks = 1U << (mp->m_allocsize_log - sbp->sb_blocklog);
 772
 773	/* set the low space thresholds for dynamic preallocation */
 774	xfs_set_low_space_thresholds(mp);
 775
 776	/*
 777	 * If enabled, sparse inode chunk alignment is expected to match the
 778	 * cluster size. Full inode chunk alignment must match the chunk size,
 779	 * but that is checked on sb read verification...
 780	 */
 781	if (xfs_has_sparseinodes(mp) &&
 782	    mp->m_sb.sb_spino_align !=
 783			XFS_B_TO_FSBT(mp, igeo->inode_cluster_size_raw)) {
 784		xfs_warn(mp,
 785	"Sparse inode block alignment (%u) must match cluster size (%llu).",
 786			 mp->m_sb.sb_spino_align,
 787			 XFS_B_TO_FSBT(mp, igeo->inode_cluster_size_raw));
 788		error = -EINVAL;
 789		goto out_remove_uuid;
 790	}
 791
 792	/*
 793	 * Check that the data (and log if separate) is an ok size.
 794	 */
 795	error = xfs_check_sizes(mp);
 796	if (error)
 797		goto out_remove_uuid;
 798
 799	/*
 800	 * Initialize realtime fields in the mount structure
 801	 */
 802	error = xfs_rtmount_init(mp);
 803	if (error) {
 804		xfs_warn(mp, "RT mount failed");
 805		goto out_remove_uuid;
 806	}
 807
 808	/*
 809	 *  Copies the low order bits of the timestamp and the randomly
 810	 *  set "sequence" number out of a UUID.
 811	 */
 812	mp->m_fixedfsid[0] =
 813		(get_unaligned_be16(&sbp->sb_uuid.b[8]) << 16) |
 814		 get_unaligned_be16(&sbp->sb_uuid.b[4]);
 815	mp->m_fixedfsid[1] = get_unaligned_be32(&sbp->sb_uuid.b[0]);
 816
 817	error = xfs_da_mount(mp);
 818	if (error) {
 819		xfs_warn(mp, "Failed dir/attr init: %d", error);
 820		goto out_remove_uuid;
 821	}
 822
 823	/*
 824	 * Initialize the precomputed transaction reservations values.
 825	 */
 826	xfs_trans_init(mp);
 827
 828	/*
 829	 * Allocate and initialize the per-ag data.
 830	 */
 831	error = xfs_initialize_perag(mp, 0, sbp->sb_agcount,
 832			mp->m_sb.sb_dblocks, &mp->m_maxagi);
 833	if (error) {
 834		xfs_warn(mp, "Failed per-ag init: %d", error);
 835		goto out_free_dir;
 836	}
 837
 838	error = xfs_initialize_rtgroups(mp, 0, sbp->sb_rgcount,
 839			mp->m_sb.sb_rextents);
 840	if (error) {
 841		xfs_warn(mp, "Failed rtgroup init: %d", error);
 842		goto out_free_perag;
 843	}
 844
 845	if (XFS_IS_CORRUPT(mp, !sbp->sb_logblocks)) {
 846		xfs_warn(mp, "no log defined");
 847		error = -EFSCORRUPTED;
 848		goto out_free_rtgroup;
 849	}
 850
 851	error = xfs_inodegc_register_shrinker(mp);
 852	if (error)
 853		goto out_fail_wait;
 854
 855	/*
 856	 * If we're resuming quota status, pick up the preliminary qflags from
 857	 * the ondisk superblock so that we know if we should recover dquots.
 858	 */
 859	if (xfs_is_resuming_quotaon(mp))
 860		xfs_qm_resume_quotaon(mp);
 861
 862	/*
 863	 * Log's mount-time initialization. The first part of recovery can place
 864	 * some items on the AIL, to be handled when recovery is finished or
 865	 * cancelled.
 866	 */
 867	error = xfs_log_mount(mp, mp->m_logdev_targp,
 868			      XFS_FSB_TO_DADDR(mp, sbp->sb_logstart),
 869			      XFS_FSB_TO_BB(mp, sbp->sb_logblocks));
 870	if (error) {
 871		xfs_warn(mp, "log mount failed");
 872		goto out_inodegc_shrinker;
 873	}
 874
 875	/*
 876	 * If we're resuming quota status and recovered the log, re-sample the
 877	 * qflags from the ondisk superblock now that we've recovered it, just
 878	 * in case someone shut down enforcement just before a crash.
 879	 */
 880	if (xfs_clear_resuming_quotaon(mp) && xlog_recovery_needed(mp->m_log))
 881		xfs_qm_resume_quotaon(mp);
 882
 883	/*
 884	 * If logged xattrs are still enabled after log recovery finishes, then
 885	 * they'll be available until unmount.  Otherwise, turn them off.
 886	 */
 887	if (xfs_sb_version_haslogxattrs(&mp->m_sb))
 888		xfs_set_using_logged_xattrs(mp);
 889	else
 890		xfs_clear_using_logged_xattrs(mp);
 891
 892	/* Enable background inode inactivation workers. */
 893	xfs_inodegc_start(mp);
 894	xfs_blockgc_start(mp);
 895
 896	/*
 897	 * Now that we've recovered any pending superblock feature bit
 898	 * additions, we can finish setting up the attr2 behaviour for the
 899	 * mount. The noattr2 option overrides the superblock flag, so only
 900	 * check the superblock feature flag if the mount option is not set.
 901	 */
 902	if (xfs_has_noattr2(mp)) {
 903		mp->m_features &= ~XFS_FEAT_ATTR2;
 904	} else if (!xfs_has_attr2(mp) &&
 905		   (mp->m_sb.sb_features2 & XFS_SB_VERSION2_ATTR2BIT)) {
 906		mp->m_features |= XFS_FEAT_ATTR2;
 907	}
 908
 909	if (xfs_has_metadir(mp)) {
 910		error = xfs_mount_setup_metadir(mp);
 911		if (error)
 912			goto out_free_metadir;
 913	}
 914
 915	/*
 916	 * Get and sanity-check the root inode.
 917	 * Save the pointer to it in the mount structure.
 918	 */
 919	error = xfs_iget(mp, NULL, sbp->sb_rootino, XFS_IGET_UNTRUSTED,
 920			 XFS_ILOCK_EXCL, &rip);
 921	if (error) {
 922		xfs_warn(mp,
 923			"Failed to read root inode 0x%llx, error %d",
 924			sbp->sb_rootino, -error);
 925		goto out_free_metadir;
 926	}
 927
 928	ASSERT(rip != NULL);
 929
 930	if (XFS_IS_CORRUPT(mp, !S_ISDIR(VFS_I(rip)->i_mode))) {
 931		xfs_warn(mp, "corrupted root inode %llu: not a directory",
 932			(unsigned long long)rip->i_ino);
 933		xfs_iunlock(rip, XFS_ILOCK_EXCL);
 934		error = -EFSCORRUPTED;
 935		goto out_rele_rip;
 936	}
 937	mp->m_rootip = rip;	/* save it */
 938
 939	xfs_iunlock(rip, XFS_ILOCK_EXCL);
 940
 941	/*
 942	 * Initialize realtime inode pointers in the mount structure
 943	 */
 944	error = xfs_rtmount_inodes(mp);
 945	if (error) {
 946		/*
 947		 * Free up the root inode.
 948		 */
 949		xfs_warn(mp, "failed to read RT inodes");
 950		goto out_rele_rip;
 951	}
 952
 953	/* Make sure the summary counts are ok. */
 954	error = xfs_check_summary_counts(mp);
 955	if (error)
 956		goto out_rtunmount;
 957
 958	/*
 959	 * If this is a read-only mount defer the superblock updates until
 960	 * the next remount into writeable mode.  Otherwise we would never
 961	 * perform the update e.g. for the root filesystem.
 962	 */
 963	if (mp->m_update_sb && !xfs_is_readonly(mp)) {
 964		error = xfs_sync_sb(mp, false);
 965		if (error) {
 966			xfs_warn(mp, "failed to write sb changes");
 967			goto out_rtunmount;
 968		}
 969	}
 970
 971	/*
 972	 * Initialise the XFS quota management subsystem for this mount
 973	 */
 974	if (XFS_IS_QUOTA_ON(mp)) {
 975		error = xfs_qm_newmount(mp, &quotamount, &quotaflags);
 976		if (error)
 977			goto out_rtunmount;
 978	} else {
 
 
 979		/*
 980		 * If a file system had quotas running earlier, but decided to
 981		 * mount without -o uquota/pquota/gquota options, revoke the
 982		 * quotachecked license.
 983		 */
 984		if (mp->m_sb.sb_qflags & XFS_ALL_QUOTA_ACCT) {
 985			xfs_notice(mp, "resetting quota flags");
 986			error = xfs_mount_reset_sbqflags(mp);
 987			if (error)
 988				goto out_rtunmount;
 989		}
 990	}
 991
 992	/*
 993	 * Finish recovering the file system.  This part needed to be delayed
 994	 * until after the root and real-time bitmap inodes were consistently
 995	 * read in.  Temporarily create per-AG space reservations for metadata
 996	 * btree shape changes because space freeing transactions (for inode
 997	 * inactivation) require the per-AG reservation in lieu of reserving
 998	 * blocks.
 999	 */
1000	error = xfs_fs_reserve_ag_blocks(mp);
1001	if (error && error == -ENOSPC)
1002		xfs_warn(mp,
1003	"ENOSPC reserving per-AG metadata pool, log recovery may fail.");
1004	error = xfs_log_mount_finish(mp);
1005	xfs_fs_unreserve_ag_blocks(mp);
1006	if (error) {
1007		xfs_warn(mp, "log mount finish failed");
1008		goto out_rtunmount;
1009	}
1010
1011	/*
1012	 * Now the log is fully replayed, we can transition to full read-only
1013	 * mode for read-only mounts. This will sync all the metadata and clean
1014	 * the log so that the recovery we just performed does not have to be
1015	 * replayed again on the next mount.
1016	 *
1017	 * We use the same quiesce mechanism as the rw->ro remount, as they are
1018	 * semantically identical operations.
1019	 */
1020	if (xfs_is_readonly(mp) && !xfs_has_norecovery(mp))
 
1021		xfs_log_clean(mp);
 
1022
1023	/*
1024	 * Complete the quota initialisation, post-log-replay component.
1025	 */
1026	if (quotamount) {
1027		ASSERT(mp->m_qflags == 0);
1028		mp->m_qflags = quotaflags;
1029
1030		xfs_qm_mount_quotas(mp);
1031	}
1032
1033	/*
1034	 * Now we are mounted, reserve a small amount of unused space for
1035	 * privileged transactions. This is needed so that transaction
1036	 * space required for critical operations can dip into this pool
1037	 * when at ENOSPC. This is needed for operations like create with
1038	 * attr, unwritten extent conversion at ENOSPC, etc. Data allocations
1039	 * are not allowed to use this reserved space.
1040	 *
1041	 * This may drive us straight to ENOSPC on mount, but that implies
1042	 * we were already there on the last unmount. Warn if this occurs.
1043	 */
1044	if (!xfs_is_readonly(mp)) {
1045		error = xfs_reserve_blocks(mp, xfs_default_resblks(mp));
 
1046		if (error)
1047			xfs_warn(mp,
1048	"Unable to allocate reserve blocks. Continuing without reserve pool.");
1049
 
 
 
 
 
 
 
 
 
1050		/* Reserve AG blocks for future btree expansion. */
1051		error = xfs_fs_reserve_ag_blocks(mp);
1052		if (error && error != -ENOSPC)
1053			goto out_agresv;
1054	}
1055
1056	return 0;
1057
1058 out_agresv:
1059	xfs_fs_unreserve_ag_blocks(mp);
 
1060	xfs_qm_unmount_quotas(mp);
1061 out_rtunmount:
1062	xfs_rtunmount_inodes(mp);
1063 out_rele_rip:
1064	xfs_irele(rip);
1065	/* Clean out dquots that might be in memory after quotacheck. */
1066	xfs_qm_unmount(mp);
1067 out_free_metadir:
1068	if (mp->m_metadirip)
1069		xfs_irele(mp->m_metadirip);
1070
1071	/*
1072	 * Inactivate all inodes that might still be in memory after a log
1073	 * intent recovery failure so that reclaim can free them.  Metadata
1074	 * inodes and the root directory shouldn't need inactivation, but the
1075	 * mount failed for some reason, so pull down all the state and flee.
1076	 */
1077	xfs_inodegc_flush(mp);
1078
1079	/*
1080	 * Flush all inode reclamation work and flush the log.
1081	 * We have to do this /after/ rtunmount and qm_unmount because those
1082	 * two will have scheduled delayed reclaim for the rt/quota inodes.
1083	 *
1084	 * This is slightly different from the unmountfs call sequence
1085	 * because we could be tearing down a partially set up mount.  In
1086	 * particular, if log_mount_finish fails we bail out without calling
1087	 * qm_unmount_quotas and therefore rely on qm_unmount to release the
1088	 * quota inodes.
1089	 */
1090	xfs_unmount_flush_inodes(mp);
 
1091	xfs_log_mount_cancel(mp);
1092 out_inodegc_shrinker:
1093	shrinker_free(mp->m_inodegc_shrinker);
1094 out_fail_wait:
1095	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp)
1096		xfs_buftarg_drain(mp->m_logdev_targp);
1097	xfs_buftarg_drain(mp->m_ddev_targp);
1098 out_free_rtgroup:
1099	xfs_free_rtgroups(mp, 0, mp->m_sb.sb_rgcount);
1100 out_free_perag:
1101	xfs_free_perag_range(mp, 0, mp->m_sb.sb_agcount);
1102 out_free_dir:
1103	xfs_da_unmount(mp);
1104 out_remove_uuid:
1105	xfs_uuid_unmount(mp);
1106 out_remove_errortag:
1107	xfs_errortag_del(mp);
1108 out_remove_error_sysfs:
1109	xfs_error_sysfs_del(mp);
1110 out_remove_scrub_stats:
1111	xchk_stats_unregister(mp->m_scrub_stats);
1112	xfs_sysfs_del(&mp->m_stats.xs_kobj);
1113 out_remove_sysfs:
1114	xfs_sysfs_del(&mp->m_kobj);
1115 out:
1116	return error;
1117}
1118
1119/*
1120 * This flushes out the inodes,dquots and the superblock, unmounts the
1121 * log and makes sure that incore structures are freed.
1122 */
1123void
1124xfs_unmountfs(
1125	struct xfs_mount	*mp)
1126{
 
1127	int			error;
1128
1129	/*
1130	 * Perform all on-disk metadata updates required to inactivate inodes
1131	 * that the VFS evicted earlier in the unmount process.  Freeing inodes
1132	 * and discarding CoW fork preallocations can cause shape changes to
1133	 * the free inode and refcount btrees, respectively, so we must finish
1134	 * this before we discard the metadata space reservations.  Metadata
1135	 * inodes and the root directory do not require inactivation.
1136	 */
1137	xfs_inodegc_flush(mp);
1138
1139	xfs_blockgc_stop(mp);
1140	xfs_fs_unreserve_ag_blocks(mp);
1141	xfs_qm_unmount_quotas(mp);
1142	xfs_rtunmount_inodes(mp);
1143	xfs_irele(mp->m_rootip);
1144	if (mp->m_metadirip)
1145		xfs_irele(mp->m_metadirip);
1146
1147	xfs_unmount_flush_inodes(mp);
1148
1149	xfs_qm_unmount(mp);
1150
1151	/*
1152	 * Unreserve any blocks we have so that when we unmount we don't account
1153	 * the reserved free space as used. This is really only necessary for
1154	 * lazy superblock counting because it trusts the incore superblock
1155	 * counters to be absolutely correct on clean unmount.
1156	 *
1157	 * We don't bother correcting this elsewhere for lazy superblock
1158	 * counting because on mount of an unclean filesystem we reconstruct the
1159	 * correct counter value and this is irrelevant.
1160	 *
1161	 * For non-lazy counter filesystems, this doesn't matter at all because
1162	 * we only every apply deltas to the superblock and hence the incore
1163	 * value does not matter....
1164	 */
1165	error = xfs_reserve_blocks(mp, 0);
 
1166	if (error)
1167		xfs_warn(mp, "Unable to free reserved block pool. "
1168				"Freespace may not be correct on next mount.");
1169	xfs_unmount_check(mp);
1170
1171	/*
1172	 * Indicate that it's ok to clear log incompat bits before cleaning
1173	 * the log and writing the unmount record.
1174	 */
1175	xfs_set_done_with_log_incompat(mp);
1176	xfs_log_unmount(mp);
1177	xfs_da_unmount(mp);
1178	xfs_uuid_unmount(mp);
1179
1180#if defined(DEBUG)
1181	xfs_errortag_clearall(mp);
1182#endif
1183	shrinker_free(mp->m_inodegc_shrinker);
1184	xfs_free_rtgroups(mp, 0, mp->m_sb.sb_rgcount);
1185	xfs_free_perag_range(mp, 0, mp->m_sb.sb_agcount);
1186	xfs_errortag_del(mp);
1187	xfs_error_sysfs_del(mp);
1188	xchk_stats_unregister(mp->m_scrub_stats);
1189	xfs_sysfs_del(&mp->m_stats.xs_kobj);
1190	xfs_sysfs_del(&mp->m_kobj);
1191}
1192
1193/*
1194 * Determine whether modifications can proceed. The caller specifies the minimum
1195 * freeze level for which modifications should not be allowed. This allows
1196 * certain operations to proceed while the freeze sequence is in progress, if
1197 * necessary.
1198 */
1199bool
1200xfs_fs_writable(
1201	struct xfs_mount	*mp,
1202	int			level)
1203{
1204	ASSERT(level > SB_UNFROZEN);
1205	if ((mp->m_super->s_writers.frozen >= level) ||
1206	    xfs_is_shutdown(mp) || xfs_is_readonly(mp))
1207		return false;
1208
1209	return true;
1210}
1211
1212void
1213xfs_add_freecounter(
1214	struct xfs_mount	*mp,
1215	struct percpu_counter	*counter,
1216	uint64_t		delta)
1217{
1218	bool			has_resv_pool = (counter == &mp->m_fdblocks);
1219	uint64_t		res_used;
1220
1221	/*
1222	 * If the reserve pool is depleted, put blocks back into it first.
1223	 * Most of the time the pool is full.
1224	 */
1225	if (!has_resv_pool || mp->m_resblks == mp->m_resblks_avail) {
1226		percpu_counter_add(counter, delta);
1227		return;
1228	}
1229
1230	spin_lock(&mp->m_sb_lock);
1231	res_used = mp->m_resblks - mp->m_resblks_avail;
1232	if (res_used > delta) {
1233		mp->m_resblks_avail += delta;
1234	} else {
1235		delta -= res_used;
1236		mp->m_resblks_avail = mp->m_resblks;
1237		percpu_counter_add(counter, delta);
1238	}
1239	spin_unlock(&mp->m_sb_lock);
1240}
1241
1242int
1243xfs_dec_freecounter(
1244	struct xfs_mount	*mp,
1245	struct percpu_counter	*counter,
1246	uint64_t		delta,
1247	bool			rsvd)
1248{
1249	int64_t			lcounter;
1250	uint64_t		set_aside = 0;
1251	s32			batch;
1252	bool			has_resv_pool;
1253
1254	ASSERT(counter == &mp->m_fdblocks || counter == &mp->m_frextents);
1255	has_resv_pool = (counter == &mp->m_fdblocks);
1256	if (rsvd)
1257		ASSERT(has_resv_pool);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1258
1259	/*
1260	 * Taking blocks away, need to be more accurate the closer we
1261	 * are to zero.
1262	 *
1263	 * If the counter has a value of less than 2 * max batch size,
1264	 * then make everything serialise as we are real close to
1265	 * ENOSPC.
1266	 */
1267	if (__percpu_counter_compare(counter, 2 * XFS_FDBLOCKS_BATCH,
1268				     XFS_FDBLOCKS_BATCH) < 0)
1269		batch = 1;
1270	else
1271		batch = XFS_FDBLOCKS_BATCH;
1272
1273	/*
1274	 * Set aside allocbt blocks because these blocks are tracked as free
1275	 * space but not available for allocation. Technically this means that a
1276	 * single reservation cannot consume all remaining free space, but the
1277	 * ratio of allocbt blocks to usable free blocks should be rather small.
1278	 * The tradeoff without this is that filesystems that maintain high
1279	 * perag block reservations can over reserve physical block availability
1280	 * and fail physical allocation, which leads to much more serious
1281	 * problems (i.e. transaction abort, pagecache discards, etc.) than
1282	 * slightly premature -ENOSPC.
1283	 */
1284	if (has_resv_pool)
1285		set_aside = xfs_fdblocks_unavailable(mp);
1286	percpu_counter_add_batch(counter, -((int64_t)delta), batch);
1287	if (__percpu_counter_compare(counter, set_aside,
1288				     XFS_FDBLOCKS_BATCH) >= 0) {
1289		/* we had space! */
1290		return 0;
1291	}
1292
1293	/*
1294	 * lock up the sb for dipping into reserves before releasing the space
1295	 * that took us to ENOSPC.
1296	 */
1297	spin_lock(&mp->m_sb_lock);
1298	percpu_counter_add(counter, delta);
1299	if (!has_resv_pool || !rsvd)
1300		goto fdblocks_enospc;
1301
1302	lcounter = (long long)mp->m_resblks_avail - delta;
1303	if (lcounter >= 0) {
1304		mp->m_resblks_avail = lcounter;
1305		spin_unlock(&mp->m_sb_lock);
1306		return 0;
1307	}
1308	xfs_warn_once(mp,
1309"Reserve blocks depleted! Consider increasing reserve pool size.");
1310
1311fdblocks_enospc:
1312	spin_unlock(&mp->m_sb_lock);
1313	return -ENOSPC;
1314}
1315
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1316/*
1317 * Used to free the superblock along various error paths.
1318 */
1319void
1320xfs_freesb(
1321	struct xfs_mount	*mp)
1322{
1323	struct xfs_buf		*bp = mp->m_sb_bp;
1324
1325	xfs_buf_lock(bp);
1326	mp->m_sb_bp = NULL;
1327	xfs_buf_relse(bp);
1328}
1329
1330/*
1331 * If the underlying (data/log/rt) device is readonly, there are some
1332 * operations that cannot proceed.
1333 */
1334int
1335xfs_dev_is_read_only(
1336	struct xfs_mount	*mp,
1337	char			*message)
1338{
1339	if (xfs_readonly_buftarg(mp->m_ddev_targp) ||
1340	    xfs_readonly_buftarg(mp->m_logdev_targp) ||
1341	    (mp->m_rtdev_targp && xfs_readonly_buftarg(mp->m_rtdev_targp))) {
1342		xfs_notice(mp, "%s required on read-only device.", message);
1343		xfs_notice(mp, "write access unavailable, cannot proceed.");
1344		return -EROFS;
1345	}
1346	return 0;
1347}
1348
1349/* Force the summary counters to be recalculated at next mount. */
1350void
1351xfs_force_summary_recalc(
1352	struct xfs_mount	*mp)
1353{
1354	if (!xfs_has_lazysbcount(mp))
1355		return;
1356
1357	xfs_fs_mark_sick(mp, XFS_SICK_FS_COUNTERS);
1358}
1359
1360/*
1361 * Enable a log incompat feature flag in the primary superblock.  The caller
1362 * cannot have any other transactions in progress.
1363 */
1364int
1365xfs_add_incompat_log_feature(
1366	struct xfs_mount	*mp,
1367	uint32_t		feature)
1368{
1369	struct xfs_dsb		*dsb;
1370	int			error;
1371
1372	ASSERT(hweight32(feature) == 1);
1373	ASSERT(!(feature & XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN));
1374
1375	/*
1376	 * Force the log to disk and kick the background AIL thread to reduce
1377	 * the chances that the bwrite will stall waiting for the AIL to unpin
1378	 * the primary superblock buffer.  This isn't a data integrity
1379	 * operation, so we don't need a synchronous push.
1380	 */
1381	error = xfs_log_force(mp, XFS_LOG_SYNC);
1382	if (error)
1383		return error;
1384	xfs_ail_push_all(mp->m_ail);
1385
1386	/*
1387	 * Lock the primary superblock buffer to serialize all callers that
1388	 * are trying to set feature bits.
1389	 */
1390	xfs_buf_lock(mp->m_sb_bp);
1391	xfs_buf_hold(mp->m_sb_bp);
1392
1393	if (xfs_is_shutdown(mp)) {
1394		error = -EIO;
1395		goto rele;
1396	}
1397
1398	if (xfs_sb_has_incompat_log_feature(&mp->m_sb, feature))
1399		goto rele;
1400
1401	/*
1402	 * Write the primary superblock to disk immediately, because we need
1403	 * the log_incompat bit to be set in the primary super now to protect
1404	 * the log items that we're going to commit later.
1405	 */
1406	dsb = mp->m_sb_bp->b_addr;
1407	xfs_sb_to_disk(dsb, &mp->m_sb);
1408	dsb->sb_features_log_incompat |= cpu_to_be32(feature);
1409	error = xfs_bwrite(mp->m_sb_bp);
1410	if (error)
1411		goto shutdown;
1412
1413	/*
1414	 * Add the feature bits to the incore superblock before we unlock the
1415	 * buffer.
1416	 */
1417	xfs_sb_add_incompat_log_features(&mp->m_sb, feature);
1418	xfs_buf_relse(mp->m_sb_bp);
1419
1420	/* Log the superblock to disk. */
1421	return xfs_sync_sb(mp, false);
1422shutdown:
1423	xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1424rele:
1425	xfs_buf_relse(mp->m_sb_bp);
1426	return error;
1427}
1428
1429/*
1430 * Clear all the log incompat flags from the superblock.
1431 *
1432 * The caller cannot be in a transaction, must ensure that the log does not
1433 * contain any log items protected by any log incompat bit, and must ensure
1434 * that there are no other threads that depend on the state of the log incompat
1435 * feature flags in the primary super.
1436 *
1437 * Returns true if the superblock is dirty.
1438 */
1439bool
1440xfs_clear_incompat_log_features(
1441	struct xfs_mount	*mp)
1442{
1443	bool			ret = false;
1444
1445	if (!xfs_has_crc(mp) ||
1446	    !xfs_sb_has_incompat_log_feature(&mp->m_sb,
1447				XFS_SB_FEAT_INCOMPAT_LOG_ALL) ||
1448	    xfs_is_shutdown(mp) ||
1449	    !xfs_is_done_with_log_incompat(mp))
1450		return false;
1451
1452	/*
1453	 * Update the incore superblock.  We synchronize on the primary super
1454	 * buffer lock to be consistent with the add function, though at least
1455	 * in theory this shouldn't be necessary.
1456	 */
1457	xfs_buf_lock(mp->m_sb_bp);
1458	xfs_buf_hold(mp->m_sb_bp);
1459
1460	if (xfs_sb_has_incompat_log_feature(&mp->m_sb,
1461				XFS_SB_FEAT_INCOMPAT_LOG_ALL)) {
1462		xfs_sb_remove_incompat_log_features(&mp->m_sb);
1463		ret = true;
1464	}
1465
1466	xfs_buf_relse(mp->m_sb_bp);
1467	return ret;
1468}
1469
1470/*
1471 * Update the in-core delayed block counter.
1472 *
1473 * We prefer to update the counter without having to take a spinlock for every
1474 * counter update (i.e. batching).  Each change to delayed allocation
1475 * reservations can change can easily exceed the default percpu counter
1476 * batching, so we use a larger batch factor here.
1477 *
1478 * Note that we don't currently have any callers requiring fast summation
1479 * (e.g. percpu_counter_read) so we can use a big batch value here.
1480 */
1481#define XFS_DELALLOC_BATCH	(4096)
1482void
1483xfs_mod_delalloc(
1484	struct xfs_inode	*ip,
1485	int64_t			data_delta,
1486	int64_t			ind_delta)
1487{
1488	struct xfs_mount	*mp = ip->i_mount;
1489
1490	if (XFS_IS_REALTIME_INODE(ip)) {
1491		percpu_counter_add_batch(&mp->m_delalloc_rtextents,
1492				xfs_blen_to_rtbxlen(mp, data_delta),
1493				XFS_DELALLOC_BATCH);
1494		if (!ind_delta)
1495			return;
1496		data_delta = 0;
1497	}
1498	percpu_counter_add_batch(&mp->m_delalloc_blks, data_delta + ind_delta,
1499			XFS_DELALLOC_BATCH);
1500}