linux/fs/xfs/xfs_mount.c
Darrick J. Wong 7993f1a431 xfs: only run COW extent recovery when there are no live extents
As part of multiple customer escalations due to file data corruption
after copy on write operations, I wrote some fstests that use fsstress
to hammer on COW to shake things loose.  Regrettably, I caught some
filesystem shutdowns due to incorrect rmap operations with the following
loop:

mount <filesystem>				# (0)
fsstress <run only readonly ops> &		# (1)
while true; do
	fsstress <run all ops>
	mount -o remount,ro			# (2)
	fsstress <run only readonly ops>
	mount -o remount,rw			# (3)
done

When (2) happens, notice that (1) is still running.  xfs_remount_ro will
call xfs_blockgc_stop to walk the inode cache to free all the COW
extents, but the blockgc mechanism races with (1)'s reader threads to
take IOLOCKs and loses, which means that it doesn't clean them all out.
Call such a file (A).

When (3) happens, xfs_remount_rw calls xfs_reflink_recover_cow, which
walks the ondisk refcount btree and frees any COW extent that it finds.
This function does not check the inode cache, which means that incore
COW forks of inode (A) is now inconsistent with the ondisk metadata.  If
one of those former COW extents are allocated and mapped into another
file (B) and someone triggers a COW to the stale reservation in (A), A's
dirty data will be written into (B) and once that's done, those blocks
will be transferred to (A)'s data fork without bumping the refcount.

The results are catastrophic -- file (B) and the refcount btree are now
corrupt.  In the first patch, we fixed the race condition in (2) so that
(A) will always flush the COW fork.  In this second patch, we move the
_recover_cow call to the initial mount call in (0) for safety.

As mentioned previously, xfs_reflink_recover_cow walks the refcount
btree looking for COW staging extents, and frees them.  This was
intended to be run at mount time (when we know there are no live inodes)
to clean up any leftover staging events that may have been left behind
during an unclean shutdown.  As a time "optimization" for readonly
mounts, we deferred this to the ro->rw transition, not realizing that
any failure to clean all COW forks during a rw->ro transition would
result in catastrophic corruption.

Therefore, remove this optimization and only run the recovery routine
when we're guaranteed not to have any COW staging extents anywhere,
which means we always run this at mount time.  While we're at it, move
the callsite to xfs_log_mount_finish because any refcount btree
expansion (however unlikely given that we're removing records from the
right side of the index) must be fed by a per-AG reservation, which
doesn't exist in its current location.

Fixes: 174edb0e46 ("xfs: store in-progress CoW allocations in the refcount btree")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2021-12-21 09:49:41 -08:00

1372 lines
36 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_bit.h"
#include "xfs_sb.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_dir2.h"
#include "xfs_ialloc.h"
#include "xfs_alloc.h"
#include "xfs_rtalloc.h"
#include "xfs_bmap.h"
#include "xfs_trans.h"
#include "xfs_trans_priv.h"
#include "xfs_log.h"
#include "xfs_error.h"
#include "xfs_quota.h"
#include "xfs_fsops.h"
#include "xfs_icache.h"
#include "xfs_sysfs.h"
#include "xfs_rmap_btree.h"
#include "xfs_refcount_btree.h"
#include "xfs_reflink.h"
#include "xfs_extent_busy.h"
#include "xfs_health.h"
#include "xfs_trace.h"
#include "xfs_ag.h"
static DEFINE_MUTEX(xfs_uuid_table_mutex);
static int xfs_uuid_table_size;
static uuid_t *xfs_uuid_table;
void
xfs_uuid_table_free(void)
{
if (xfs_uuid_table_size == 0)
return;
kmem_free(xfs_uuid_table);
xfs_uuid_table = NULL;
xfs_uuid_table_size = 0;
}
/*
* See if the UUID is unique among mounted XFS filesystems.
* Mount fails if UUID is nil or a FS with the same UUID is already mounted.
*/
STATIC int
xfs_uuid_mount(
struct xfs_mount *mp)
{
uuid_t *uuid = &mp->m_sb.sb_uuid;
int hole, i;
/* Publish UUID in struct super_block */
uuid_copy(&mp->m_super->s_uuid, uuid);
if (xfs_has_nouuid(mp))
return 0;
if (uuid_is_null(uuid)) {
xfs_warn(mp, "Filesystem has null UUID - can't mount");
return -EINVAL;
}
mutex_lock(&xfs_uuid_table_mutex);
for (i = 0, hole = -1; i < xfs_uuid_table_size; i++) {
if (uuid_is_null(&xfs_uuid_table[i])) {
hole = i;
continue;
}
if (uuid_equal(uuid, &xfs_uuid_table[i]))
goto out_duplicate;
}
if (hole < 0) {
xfs_uuid_table = krealloc(xfs_uuid_table,
(xfs_uuid_table_size + 1) * sizeof(*xfs_uuid_table),
GFP_KERNEL | __GFP_NOFAIL);
hole = xfs_uuid_table_size++;
}
xfs_uuid_table[hole] = *uuid;
mutex_unlock(&xfs_uuid_table_mutex);
return 0;
out_duplicate:
mutex_unlock(&xfs_uuid_table_mutex);
xfs_warn(mp, "Filesystem has duplicate UUID %pU - can't mount", uuid);
return -EINVAL;
}
STATIC void
xfs_uuid_unmount(
struct xfs_mount *mp)
{
uuid_t *uuid = &mp->m_sb.sb_uuid;
int i;
if (xfs_has_nouuid(mp))
return;
mutex_lock(&xfs_uuid_table_mutex);
for (i = 0; i < xfs_uuid_table_size; i++) {
if (uuid_is_null(&xfs_uuid_table[i]))
continue;
if (!uuid_equal(uuid, &xfs_uuid_table[i]))
continue;
memset(&xfs_uuid_table[i], 0, sizeof(uuid_t));
break;
}
ASSERT(i < xfs_uuid_table_size);
mutex_unlock(&xfs_uuid_table_mutex);
}
/*
* Check size of device based on the (data/realtime) block count.
* Note: this check is used by the growfs code as well as mount.
*/
int
xfs_sb_validate_fsb_count(
xfs_sb_t *sbp,
uint64_t nblocks)
{
ASSERT(PAGE_SHIFT >= sbp->sb_blocklog);
ASSERT(sbp->sb_blocklog >= BBSHIFT);
/* Limited by ULONG_MAX of page cache index */
if (nblocks >> (PAGE_SHIFT - sbp->sb_blocklog) > ULONG_MAX)
return -EFBIG;
return 0;
}
/*
* xfs_readsb
*
* Does the initial read of the superblock.
*/
int
xfs_readsb(
struct xfs_mount *mp,
int flags)
{
unsigned int sector_size;
struct xfs_buf *bp;
struct xfs_sb *sbp = &mp->m_sb;
int error;
int loud = !(flags & XFS_MFSI_QUIET);
const struct xfs_buf_ops *buf_ops;
ASSERT(mp->m_sb_bp == NULL);
ASSERT(mp->m_ddev_targp != NULL);
/*
* For the initial read, we must guess at the sector
* size based on the block device. It's enough to
* get the sb_sectsize out of the superblock and
* then reread with the proper length.
* We don't verify it yet, because it may not be complete.
*/
sector_size = xfs_getsize_buftarg(mp->m_ddev_targp);
buf_ops = NULL;
/*
* Allocate a (locked) buffer to hold the superblock. This will be kept
* around at all times to optimize access to the superblock. Therefore,
* set XBF_NO_IOACCT to make sure it doesn't hold the buftarg count
* elevated.
*/
reread:
error = xfs_buf_read_uncached(mp->m_ddev_targp, XFS_SB_DADDR,
BTOBB(sector_size), XBF_NO_IOACCT, &bp,
buf_ops);
if (error) {
if (loud)
xfs_warn(mp, "SB validate failed with error %d.", error);
/* bad CRC means corrupted metadata */
if (error == -EFSBADCRC)
error = -EFSCORRUPTED;
return error;
}
/*
* Initialize the mount structure from the superblock.
*/
xfs_sb_from_disk(sbp, bp->b_addr);
/*
* If we haven't validated the superblock, do so now before we try
* to check the sector size and reread the superblock appropriately.
*/
if (sbp->sb_magicnum != XFS_SB_MAGIC) {
if (loud)
xfs_warn(mp, "Invalid superblock magic number");
error = -EINVAL;
goto release_buf;
}
/*
* We must be able to do sector-sized and sector-aligned IO.
*/
if (sector_size > sbp->sb_sectsize) {
if (loud)
xfs_warn(mp, "device supports %u byte sectors (not %u)",
sector_size, sbp->sb_sectsize);
error = -ENOSYS;
goto release_buf;
}
if (buf_ops == NULL) {
/*
* Re-read the superblock so the buffer is correctly sized,
* and properly verified.
*/
xfs_buf_relse(bp);
sector_size = sbp->sb_sectsize;
buf_ops = loud ? &xfs_sb_buf_ops : &xfs_sb_quiet_buf_ops;
goto reread;
}
mp->m_features |= xfs_sb_version_to_features(sbp);
xfs_reinit_percpu_counters(mp);
/* no need to be quiet anymore, so reset the buf ops */
bp->b_ops = &xfs_sb_buf_ops;
mp->m_sb_bp = bp;
xfs_buf_unlock(bp);
return 0;
release_buf:
xfs_buf_relse(bp);
return error;
}
/*
* If the sunit/swidth change would move the precomputed root inode value, we
* must reject the ondisk change because repair will stumble over that.
* However, we allow the mount to proceed because we never rejected this
* combination before. Returns true to update the sb, false otherwise.
*/
static inline int
xfs_check_new_dalign(
struct xfs_mount *mp,
int new_dalign,
bool *update_sb)
{
struct xfs_sb *sbp = &mp->m_sb;
xfs_ino_t calc_ino;
calc_ino = xfs_ialloc_calc_rootino(mp, new_dalign);
trace_xfs_check_new_dalign(mp, new_dalign, calc_ino);
if (sbp->sb_rootino == calc_ino) {
*update_sb = true;
return 0;
}
xfs_warn(mp,
"Cannot change stripe alignment; would require moving root inode.");
/*
* XXX: Next time we add a new incompat feature, this should start
* returning -EINVAL to fail the mount. Until then, spit out a warning
* that we're ignoring the administrator's instructions.
*/
xfs_warn(mp, "Skipping superblock stripe alignment update.");
*update_sb = false;
return 0;
}
/*
* If we were provided with new sunit/swidth values as mount options, make sure
* that they pass basic alignment and superblock feature checks, and convert
* them into the same units (FSB) that everything else expects. This step
* /must/ be done before computing the inode geometry.
*/
STATIC int
xfs_validate_new_dalign(
struct xfs_mount *mp)
{
if (mp->m_dalign == 0)
return 0;
/*
* If stripe unit and stripe width are not multiples
* of the fs blocksize turn off alignment.
*/
if ((BBTOB(mp->m_dalign) & mp->m_blockmask) ||
(BBTOB(mp->m_swidth) & mp->m_blockmask)) {
xfs_warn(mp,
"alignment check failed: sunit/swidth vs. blocksize(%d)",
mp->m_sb.sb_blocksize);
return -EINVAL;
} else {
/*
* Convert the stripe unit and width to FSBs.
*/
mp->m_dalign = XFS_BB_TO_FSBT(mp, mp->m_dalign);
if (mp->m_dalign && (mp->m_sb.sb_agblocks % mp->m_dalign)) {
xfs_warn(mp,
"alignment check failed: sunit/swidth vs. agsize(%d)",
mp->m_sb.sb_agblocks);
return -EINVAL;
} else if (mp->m_dalign) {
mp->m_swidth = XFS_BB_TO_FSBT(mp, mp->m_swidth);
} else {
xfs_warn(mp,
"alignment check failed: sunit(%d) less than bsize(%d)",
mp->m_dalign, mp->m_sb.sb_blocksize);
return -EINVAL;
}
}
if (!xfs_has_dalign(mp)) {
xfs_warn(mp,
"cannot change alignment: superblock does not support data alignment");
return -EINVAL;
}
return 0;
}
/* Update alignment values based on mount options and sb values. */
STATIC int
xfs_update_alignment(
struct xfs_mount *mp)
{
struct xfs_sb *sbp = &mp->m_sb;
if (mp->m_dalign) {
bool update_sb;
int error;
if (sbp->sb_unit == mp->m_dalign &&
sbp->sb_width == mp->m_swidth)
return 0;
error = xfs_check_new_dalign(mp, mp->m_dalign, &update_sb);
if (error || !update_sb)
return error;
sbp->sb_unit = mp->m_dalign;
sbp->sb_width = mp->m_swidth;
mp->m_update_sb = true;
} else if (!xfs_has_noalign(mp) && xfs_has_dalign(mp)) {
mp->m_dalign = sbp->sb_unit;
mp->m_swidth = sbp->sb_width;
}
return 0;
}
/*
* precalculate the low space thresholds for dynamic speculative preallocation.
*/
void
xfs_set_low_space_thresholds(
struct xfs_mount *mp)
{
uint64_t dblocks = mp->m_sb.sb_dblocks;
uint64_t rtexts = mp->m_sb.sb_rextents;
int i;
do_div(dblocks, 100);
do_div(rtexts, 100);
for (i = 0; i < XFS_LOWSP_MAX; i++) {
mp->m_low_space[i] = dblocks * (i + 1);
mp->m_low_rtexts[i] = rtexts * (i + 1);
}
}
/*
* Check that the data (and log if separate) is an ok size.
*/
STATIC int
xfs_check_sizes(
struct xfs_mount *mp)
{
struct xfs_buf *bp;
xfs_daddr_t d;
int error;
d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks);
if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_dblocks) {
xfs_warn(mp, "filesystem size mismatch detected");
return -EFBIG;
}
error = xfs_buf_read_uncached(mp->m_ddev_targp,
d - XFS_FSS_TO_BB(mp, 1),
XFS_FSS_TO_BB(mp, 1), 0, &bp, NULL);
if (error) {
xfs_warn(mp, "last sector read failed");
return error;
}
xfs_buf_relse(bp);
if (mp->m_logdev_targp == mp->m_ddev_targp)
return 0;
d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_logblocks);
if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_logblocks) {
xfs_warn(mp, "log size mismatch detected");
return -EFBIG;
}
error = xfs_buf_read_uncached(mp->m_logdev_targp,
d - XFS_FSB_TO_BB(mp, 1),
XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
if (error) {
xfs_warn(mp, "log device read failed");
return error;
}
xfs_buf_relse(bp);
return 0;
}
/*
* Clear the quotaflags in memory and in the superblock.
*/
int
xfs_mount_reset_sbqflags(
struct xfs_mount *mp)
{
mp->m_qflags = 0;
/* It is OK to look at sb_qflags in the mount path without m_sb_lock. */
if (mp->m_sb.sb_qflags == 0)
return 0;
spin_lock(&mp->m_sb_lock);
mp->m_sb.sb_qflags = 0;
spin_unlock(&mp->m_sb_lock);
if (!xfs_fs_writable(mp, SB_FREEZE_WRITE))
return 0;
return xfs_sync_sb(mp, false);
}
uint64_t
xfs_default_resblks(xfs_mount_t *mp)
{
uint64_t resblks;
/*
* We default to 5% or 8192 fsbs of space reserved, whichever is
* smaller. This is intended to cover concurrent allocation
* transactions when we initially hit enospc. These each require a 4
* block reservation. Hence by default we cover roughly 2000 concurrent
* allocation reservations.
*/
resblks = mp->m_sb.sb_dblocks;
do_div(resblks, 20);
resblks = min_t(uint64_t, resblks, 8192);
return resblks;
}
/* Ensure the summary counts are correct. */
STATIC int
xfs_check_summary_counts(
struct xfs_mount *mp)
{
/*
* The AG0 superblock verifier rejects in-progress filesystems,
* so we should never see the flag set this far into mounting.
*/
if (mp->m_sb.sb_inprogress) {
xfs_err(mp, "sb_inprogress set after log recovery??");
WARN_ON(1);
return -EFSCORRUPTED;
}
/*
* Now the log is mounted, we know if it was an unclean shutdown or
* not. If it was, with the first phase of recovery has completed, we
* have consistent AG blocks on disk. We have not recovered EFIs yet,
* but they are recovered transactionally in the second recovery phase
* later.
*
* If the log was clean when we mounted, we can check the summary
* counters. If any of them are obviously incorrect, we can recompute
* them from the AGF headers in the next step.
*/
if (xfs_is_clean(mp) &&
(mp->m_sb.sb_fdblocks > mp->m_sb.sb_dblocks ||
!xfs_verify_icount(mp, mp->m_sb.sb_icount) ||
mp->m_sb.sb_ifree > mp->m_sb.sb_icount))
xfs_fs_mark_sick(mp, XFS_SICK_FS_COUNTERS);
/*
* We can safely re-initialise incore superblock counters from the
* per-ag data. These may not be correct if the filesystem was not
* cleanly unmounted, so we waited for recovery to finish before doing
* this.
*
* If the filesystem was cleanly unmounted or the previous check did
* not flag anything weird, then we can trust the values in the
* superblock to be correct and we don't need to do anything here.
* Otherwise, recalculate the summary counters.
*/
if ((!xfs_has_lazysbcount(mp) || xfs_is_clean(mp)) &&
!xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS))
return 0;
return xfs_initialize_perag_data(mp, mp->m_sb.sb_agcount);
}
/*
* Flush and reclaim dirty inodes in preparation for unmount. Inodes and
* internal inode structures can be sitting in the CIL and AIL at this point,
* so we need to unpin them, write them back and/or reclaim them before unmount
* can proceed. In other words, callers are required to have inactivated all
* inodes.
*
* An inode cluster that has been freed can have its buffer still pinned in
* memory because the transaction is still sitting in a iclog. The stale inodes
* on that buffer will be pinned to the buffer until the transaction hits the
* disk and the callbacks run. Pushing the AIL will skip the stale inodes and
* may never see the pinned buffer, so nothing will push out the iclog and
* unpin the buffer.
*
* Hence we need to force the log to unpin everything first. However, log
* forces don't wait for the discards they issue to complete, so we have to
* explicitly wait for them to complete here as well.
*
* Then we can tell the world we are unmounting so that error handling knows
* that the filesystem is going away and we should error out anything that we
* have been retrying in the background. This will prevent never-ending
* retries in AIL pushing from hanging the unmount.
*
* Finally, we can push the AIL to clean all the remaining dirty objects, then
* reclaim the remaining inodes that are still in memory at this point in time.
*/
static void
xfs_unmount_flush_inodes(
struct xfs_mount *mp)
{
xfs_log_force(mp, XFS_LOG_SYNC);
xfs_extent_busy_wait_all(mp);
flush_workqueue(xfs_discard_wq);
set_bit(XFS_OPSTATE_UNMOUNTING, &mp->m_opstate);
xfs_ail_push_all_sync(mp->m_ail);
xfs_inodegc_stop(mp);
cancel_delayed_work_sync(&mp->m_reclaim_work);
xfs_reclaim_inodes(mp);
xfs_health_unmount(mp);
}
static void
xfs_mount_setup_inode_geom(
struct xfs_mount *mp)
{
struct xfs_ino_geometry *igeo = M_IGEO(mp);
igeo->attr_fork_offset = xfs_bmap_compute_attr_offset(mp);
ASSERT(igeo->attr_fork_offset < XFS_LITINO(mp));
xfs_ialloc_setup_geometry(mp);
}
/* Compute maximum possible height for per-AG btree types for this fs. */
static inline void
xfs_agbtree_compute_maxlevels(
struct xfs_mount *mp)
{
unsigned int levels;
levels = max(mp->m_alloc_maxlevels, M_IGEO(mp)->inobt_maxlevels);
levels = max(levels, mp->m_rmap_maxlevels);
mp->m_agbtree_maxlevels = max(levels, mp->m_refc_maxlevels);
}
/*
* This function does the following on an initial mount of a file system:
* - reads the superblock from disk and init the mount struct
* - if we're a 32-bit kernel, do a size check on the superblock
* so we don't mount terabyte filesystems
* - init mount struct realtime fields
* - allocate inode hash table for fs
* - init directory manager
* - perform recovery and init the log manager
*/
int
xfs_mountfs(
struct xfs_mount *mp)
{
struct xfs_sb *sbp = &(mp->m_sb);
struct xfs_inode *rip;
struct xfs_ino_geometry *igeo = M_IGEO(mp);
uint64_t resblks;
uint quotamount = 0;
uint quotaflags = 0;
int error = 0;
xfs_sb_mount_common(mp, sbp);
/*
* Check for a mismatched features2 values. Older kernels read & wrote
* into the wrong sb offset for sb_features2 on some platforms due to
* xfs_sb_t not being 64bit size aligned when sb_features2 was added,
* which made older superblock reading/writing routines swap it as a
* 64-bit value.
*
* For backwards compatibility, we make both slots equal.
*
* If we detect a mismatched field, we OR the set bits into the existing
* features2 field in case it has already been modified; we don't want
* to lose any features. We then update the bad location with the ORed
* value so that older kernels will see any features2 flags. The
* superblock writeback code ensures the new sb_features2 is copied to
* sb_bad_features2 before it is logged or written to disk.
*/
if (xfs_sb_has_mismatched_features2(sbp)) {
xfs_warn(mp, "correcting sb_features alignment problem");
sbp->sb_features2 |= sbp->sb_bad_features2;
mp->m_update_sb = true;
}
/* always use v2 inodes by default now */
if (!(mp->m_sb.sb_versionnum & XFS_SB_VERSION_NLINKBIT)) {
mp->m_sb.sb_versionnum |= XFS_SB_VERSION_NLINKBIT;
mp->m_features |= XFS_FEAT_NLINK;
mp->m_update_sb = true;
}
/*
* If we were given new sunit/swidth options, do some basic validation
* checks and convert the incore dalign and swidth values to the
* same units (FSB) that everything else uses. This /must/ happen
* before computing the inode geometry.
*/
error = xfs_validate_new_dalign(mp);
if (error)
goto out;
xfs_alloc_compute_maxlevels(mp);
xfs_bmap_compute_maxlevels(mp, XFS_DATA_FORK);
xfs_bmap_compute_maxlevels(mp, XFS_ATTR_FORK);
xfs_mount_setup_inode_geom(mp);
xfs_rmapbt_compute_maxlevels(mp);
xfs_refcountbt_compute_maxlevels(mp);
xfs_agbtree_compute_maxlevels(mp);
/*
* Check if sb_agblocks is aligned at stripe boundary. If sb_agblocks
* is NOT aligned turn off m_dalign since allocator alignment is within
* an ag, therefore ag has to be aligned at stripe boundary. Note that
* we must compute the free space and rmap btree geometry before doing
* this.
*/
error = xfs_update_alignment(mp);
if (error)
goto out;
/* enable fail_at_unmount as default */
mp->m_fail_unmount = true;
error = xfs_sysfs_init(&mp->m_kobj, &xfs_mp_ktype,
NULL, mp->m_super->s_id);
if (error)
goto out;
error = xfs_sysfs_init(&mp->m_stats.xs_kobj, &xfs_stats_ktype,
&mp->m_kobj, "stats");
if (error)
goto out_remove_sysfs;
error = xfs_error_sysfs_init(mp);
if (error)
goto out_del_stats;
error = xfs_errortag_init(mp);
if (error)
goto out_remove_error_sysfs;
error = xfs_uuid_mount(mp);
if (error)
goto out_remove_errortag;
/*
* Update the preferred write size based on the information from the
* on-disk superblock.
*/
mp->m_allocsize_log =
max_t(uint32_t, sbp->sb_blocklog, mp->m_allocsize_log);
mp->m_allocsize_blocks = 1U << (mp->m_allocsize_log - sbp->sb_blocklog);
/* set the low space thresholds for dynamic preallocation */
xfs_set_low_space_thresholds(mp);
/*
* If enabled, sparse inode chunk alignment is expected to match the
* cluster size. Full inode chunk alignment must match the chunk size,
* but that is checked on sb read verification...
*/
if (xfs_has_sparseinodes(mp) &&
mp->m_sb.sb_spino_align !=
XFS_B_TO_FSBT(mp, igeo->inode_cluster_size_raw)) {
xfs_warn(mp,
"Sparse inode block alignment (%u) must match cluster size (%llu).",
mp->m_sb.sb_spino_align,
XFS_B_TO_FSBT(mp, igeo->inode_cluster_size_raw));
error = -EINVAL;
goto out_remove_uuid;
}
/*
* Check that the data (and log if separate) is an ok size.
*/
error = xfs_check_sizes(mp);
if (error)
goto out_remove_uuid;
/*
* Initialize realtime fields in the mount structure
*/
error = xfs_rtmount_init(mp);
if (error) {
xfs_warn(mp, "RT mount failed");
goto out_remove_uuid;
}
/*
* Copies the low order bits of the timestamp and the randomly
* set "sequence" number out of a UUID.
*/
mp->m_fixedfsid[0] =
(get_unaligned_be16(&sbp->sb_uuid.b[8]) << 16) |
get_unaligned_be16(&sbp->sb_uuid.b[4]);
mp->m_fixedfsid[1] = get_unaligned_be32(&sbp->sb_uuid.b[0]);
error = xfs_da_mount(mp);
if (error) {
xfs_warn(mp, "Failed dir/attr init: %d", error);
goto out_remove_uuid;
}
/*
* Initialize the precomputed transaction reservations values.
*/
xfs_trans_init(mp);
/*
* Allocate and initialize the per-ag data.
*/
error = xfs_initialize_perag(mp, sbp->sb_agcount, &mp->m_maxagi);
if (error) {
xfs_warn(mp, "Failed per-ag init: %d", error);
goto out_free_dir;
}
if (XFS_IS_CORRUPT(mp, !sbp->sb_logblocks)) {
xfs_warn(mp, "no log defined");
error = -EFSCORRUPTED;
goto out_free_perag;
}
error = xfs_inodegc_register_shrinker(mp);
if (error)
goto out_fail_wait;
/*
* Log's mount-time initialization. The first part of recovery can place
* some items on the AIL, to be handled when recovery is finished or
* cancelled.
*/
error = xfs_log_mount(mp, mp->m_logdev_targp,
XFS_FSB_TO_DADDR(mp, sbp->sb_logstart),
XFS_FSB_TO_BB(mp, sbp->sb_logblocks));
if (error) {
xfs_warn(mp, "log mount failed");
goto out_inodegc_shrinker;
}
/* Make sure the summary counts are ok. */
error = xfs_check_summary_counts(mp);
if (error)
goto out_log_dealloc;
/* Enable background inode inactivation workers. */
xfs_inodegc_start(mp);
xfs_blockgc_start(mp);
/*
* Now that we've recovered any pending superblock feature bit
* additions, we can finish setting up the attr2 behaviour for the
* mount. The noattr2 option overrides the superblock flag, so only
* check the superblock feature flag if the mount option is not set.
*/
if (xfs_has_noattr2(mp)) {
mp->m_features &= ~XFS_FEAT_ATTR2;
} else if (!xfs_has_attr2(mp) &&
(mp->m_sb.sb_features2 & XFS_SB_VERSION2_ATTR2BIT)) {
mp->m_features |= XFS_FEAT_ATTR2;
}
/*
* Get and sanity-check the root inode.
* Save the pointer to it in the mount structure.
*/
error = xfs_iget(mp, NULL, sbp->sb_rootino, XFS_IGET_UNTRUSTED,
XFS_ILOCK_EXCL, &rip);
if (error) {
xfs_warn(mp,
"Failed to read root inode 0x%llx, error %d",
sbp->sb_rootino, -error);
goto out_log_dealloc;
}
ASSERT(rip != NULL);
if (XFS_IS_CORRUPT(mp, !S_ISDIR(VFS_I(rip)->i_mode))) {
xfs_warn(mp, "corrupted root inode %llu: not a directory",
(unsigned long long)rip->i_ino);
xfs_iunlock(rip, XFS_ILOCK_EXCL);
error = -EFSCORRUPTED;
goto out_rele_rip;
}
mp->m_rootip = rip; /* save it */
xfs_iunlock(rip, XFS_ILOCK_EXCL);
/*
* Initialize realtime inode pointers in the mount structure
*/
error = xfs_rtmount_inodes(mp);
if (error) {
/*
* Free up the root inode.
*/
xfs_warn(mp, "failed to read RT inodes");
goto out_rele_rip;
}
/*
* If this is a read-only mount defer the superblock updates until
* the next remount into writeable mode. Otherwise we would never
* perform the update e.g. for the root filesystem.
*/
if (mp->m_update_sb && !xfs_is_readonly(mp)) {
error = xfs_sync_sb(mp, false);
if (error) {
xfs_warn(mp, "failed to write sb changes");
goto out_rtunmount;
}
}
/*
* Initialise the XFS quota management subsystem for this mount
*/
if (XFS_IS_QUOTA_ON(mp)) {
error = xfs_qm_newmount(mp, &quotamount, &quotaflags);
if (error)
goto out_rtunmount;
} else {
/*
* If a file system had quotas running earlier, but decided to
* mount without -o uquota/pquota/gquota options, revoke the
* quotachecked license.
*/
if (mp->m_sb.sb_qflags & XFS_ALL_QUOTA_ACCT) {
xfs_notice(mp, "resetting quota flags");
error = xfs_mount_reset_sbqflags(mp);
if (error)
goto out_rtunmount;
}
}
/*
* Finish recovering the file system. This part needed to be delayed
* until after the root and real-time bitmap inodes were consistently
* read in. Temporarily create per-AG space reservations for metadata
* btree shape changes because space freeing transactions (for inode
* inactivation) require the per-AG reservation in lieu of reserving
* blocks.
*/
error = xfs_fs_reserve_ag_blocks(mp);
if (error && error == -ENOSPC)
xfs_warn(mp,
"ENOSPC reserving per-AG metadata pool, log recovery may fail.");
error = xfs_log_mount_finish(mp);
xfs_fs_unreserve_ag_blocks(mp);
if (error) {
xfs_warn(mp, "log mount finish failed");
goto out_rtunmount;
}
/*
* Now the log is fully replayed, we can transition to full read-only
* mode for read-only mounts. This will sync all the metadata and clean
* the log so that the recovery we just performed does not have to be
* replayed again on the next mount.
*
* We use the same quiesce mechanism as the rw->ro remount, as they are
* semantically identical operations.
*/
if (xfs_is_readonly(mp) && !xfs_has_norecovery(mp))
xfs_log_clean(mp);
/*
* Complete the quota initialisation, post-log-replay component.
*/
if (quotamount) {
ASSERT(mp->m_qflags == 0);
mp->m_qflags = quotaflags;
xfs_qm_mount_quotas(mp);
}
/*
* Now we are mounted, reserve a small amount of unused space for
* privileged transactions. This is needed so that transaction
* space required for critical operations can dip into this pool
* when at ENOSPC. This is needed for operations like create with
* attr, unwritten extent conversion at ENOSPC, etc. Data allocations
* are not allowed to use this reserved space.
*
* This may drive us straight to ENOSPC on mount, but that implies
* we were already there on the last unmount. Warn if this occurs.
*/
if (!xfs_is_readonly(mp)) {
resblks = xfs_default_resblks(mp);
error = xfs_reserve_blocks(mp, &resblks, NULL);
if (error)
xfs_warn(mp,
"Unable to allocate reserve blocks. Continuing without reserve pool.");
/* Reserve AG blocks for future btree expansion. */
error = xfs_fs_reserve_ag_blocks(mp);
if (error && error != -ENOSPC)
goto out_agresv;
}
return 0;
out_agresv:
xfs_fs_unreserve_ag_blocks(mp);
xfs_qm_unmount_quotas(mp);
out_rtunmount:
xfs_rtunmount_inodes(mp);
out_rele_rip:
xfs_irele(rip);
/* Clean out dquots that might be in memory after quotacheck. */
xfs_qm_unmount(mp);
/*
* Inactivate all inodes that might still be in memory after a log
* intent recovery failure so that reclaim can free them. Metadata
* inodes and the root directory shouldn't need inactivation, but the
* mount failed for some reason, so pull down all the state and flee.
*/
xfs_inodegc_flush(mp);
/*
* Flush all inode reclamation work and flush the log.
* We have to do this /after/ rtunmount and qm_unmount because those
* two will have scheduled delayed reclaim for the rt/quota inodes.
*
* This is slightly different from the unmountfs call sequence
* because we could be tearing down a partially set up mount. In
* particular, if log_mount_finish fails we bail out without calling
* qm_unmount_quotas and therefore rely on qm_unmount to release the
* quota inodes.
*/
xfs_unmount_flush_inodes(mp);
out_log_dealloc:
xfs_log_mount_cancel(mp);
out_inodegc_shrinker:
unregister_shrinker(&mp->m_inodegc_shrinker);
out_fail_wait:
if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp)
xfs_buftarg_drain(mp->m_logdev_targp);
xfs_buftarg_drain(mp->m_ddev_targp);
out_free_perag:
xfs_free_perag(mp);
out_free_dir:
xfs_da_unmount(mp);
out_remove_uuid:
xfs_uuid_unmount(mp);
out_remove_errortag:
xfs_errortag_del(mp);
out_remove_error_sysfs:
xfs_error_sysfs_del(mp);
out_del_stats:
xfs_sysfs_del(&mp->m_stats.xs_kobj);
out_remove_sysfs:
xfs_sysfs_del(&mp->m_kobj);
out:
return error;
}
/*
* This flushes out the inodes,dquots and the superblock, unmounts the
* log and makes sure that incore structures are freed.
*/
void
xfs_unmountfs(
struct xfs_mount *mp)
{
uint64_t resblks;
int error;
/*
* Perform all on-disk metadata updates required to inactivate inodes
* that the VFS evicted earlier in the unmount process. Freeing inodes
* and discarding CoW fork preallocations can cause shape changes to
* the free inode and refcount btrees, respectively, so we must finish
* this before we discard the metadata space reservations. Metadata
* inodes and the root directory do not require inactivation.
*/
xfs_inodegc_flush(mp);
xfs_blockgc_stop(mp);
xfs_fs_unreserve_ag_blocks(mp);
xfs_qm_unmount_quotas(mp);
xfs_rtunmount_inodes(mp);
xfs_irele(mp->m_rootip);
xfs_unmount_flush_inodes(mp);
xfs_qm_unmount(mp);
/*
* Unreserve any blocks we have so that when we unmount we don't account
* the reserved free space as used. This is really only necessary for
* lazy superblock counting because it trusts the incore superblock
* counters to be absolutely correct on clean unmount.
*
* We don't bother correcting this elsewhere for lazy superblock
* counting because on mount of an unclean filesystem we reconstruct the
* correct counter value and this is irrelevant.
*
* For non-lazy counter filesystems, this doesn't matter at all because
* we only every apply deltas to the superblock and hence the incore
* value does not matter....
*/
resblks = 0;
error = xfs_reserve_blocks(mp, &resblks, NULL);
if (error)
xfs_warn(mp, "Unable to free reserved block pool. "
"Freespace may not be correct on next mount.");
xfs_log_unmount(mp);
xfs_da_unmount(mp);
xfs_uuid_unmount(mp);
#if defined(DEBUG)
xfs_errortag_clearall(mp);
#endif
unregister_shrinker(&mp->m_inodegc_shrinker);
xfs_free_perag(mp);
xfs_errortag_del(mp);
xfs_error_sysfs_del(mp);
xfs_sysfs_del(&mp->m_stats.xs_kobj);
xfs_sysfs_del(&mp->m_kobj);
}
/*
* Determine whether modifications can proceed. The caller specifies the minimum
* freeze level for which modifications should not be allowed. This allows
* certain operations to proceed while the freeze sequence is in progress, if
* necessary.
*/
bool
xfs_fs_writable(
struct xfs_mount *mp,
int level)
{
ASSERT(level > SB_UNFROZEN);
if ((mp->m_super->s_writers.frozen >= level) ||
xfs_is_shutdown(mp) || xfs_is_readonly(mp))
return false;
return true;
}
int
xfs_mod_fdblocks(
struct xfs_mount *mp,
int64_t delta,
bool rsvd)
{
int64_t lcounter;
long long res_used;
s32 batch;
uint64_t set_aside;
if (delta > 0) {
/*
* If the reserve pool is depleted, put blocks back into it
* first. Most of the time the pool is full.
*/
if (likely(mp->m_resblks == mp->m_resblks_avail)) {
percpu_counter_add(&mp->m_fdblocks, delta);
return 0;
}
spin_lock(&mp->m_sb_lock);
res_used = (long long)(mp->m_resblks - mp->m_resblks_avail);
if (res_used > delta) {
mp->m_resblks_avail += delta;
} else {
delta -= res_used;
mp->m_resblks_avail = mp->m_resblks;
percpu_counter_add(&mp->m_fdblocks, delta);
}
spin_unlock(&mp->m_sb_lock);
return 0;
}
/*
* Taking blocks away, need to be more accurate the closer we
* are to zero.
*
* If the counter has a value of less than 2 * max batch size,
* then make everything serialise as we are real close to
* ENOSPC.
*/
if (__percpu_counter_compare(&mp->m_fdblocks, 2 * XFS_FDBLOCKS_BATCH,
XFS_FDBLOCKS_BATCH) < 0)
batch = 1;
else
batch = XFS_FDBLOCKS_BATCH;
/*
* Set aside allocbt blocks because these blocks are tracked as free
* space but not available for allocation. Technically this means that a
* single reservation cannot consume all remaining free space, but the
* ratio of allocbt blocks to usable free blocks should be rather small.
* The tradeoff without this is that filesystems that maintain high
* perag block reservations can over reserve physical block availability
* and fail physical allocation, which leads to much more serious
* problems (i.e. transaction abort, pagecache discards, etc.) than
* slightly premature -ENOSPC.
*/
set_aside = mp->m_alloc_set_aside + atomic64_read(&mp->m_allocbt_blks);
percpu_counter_add_batch(&mp->m_fdblocks, delta, batch);
if (__percpu_counter_compare(&mp->m_fdblocks, set_aside,
XFS_FDBLOCKS_BATCH) >= 0) {
/* we had space! */
return 0;
}
/*
* lock up the sb for dipping into reserves before releasing the space
* that took us to ENOSPC.
*/
spin_lock(&mp->m_sb_lock);
percpu_counter_add(&mp->m_fdblocks, -delta);
if (!rsvd)
goto fdblocks_enospc;
lcounter = (long long)mp->m_resblks_avail + delta;
if (lcounter >= 0) {
mp->m_resblks_avail = lcounter;
spin_unlock(&mp->m_sb_lock);
return 0;
}
xfs_warn_once(mp,
"Reserve blocks depleted! Consider increasing reserve pool size.");
fdblocks_enospc:
spin_unlock(&mp->m_sb_lock);
return -ENOSPC;
}
int
xfs_mod_frextents(
struct xfs_mount *mp,
int64_t delta)
{
int64_t lcounter;
int ret = 0;
spin_lock(&mp->m_sb_lock);
lcounter = mp->m_sb.sb_frextents + delta;
if (lcounter < 0)
ret = -ENOSPC;
else
mp->m_sb.sb_frextents = lcounter;
spin_unlock(&mp->m_sb_lock);
return ret;
}
/*
* Used to free the superblock along various error paths.
*/
void
xfs_freesb(
struct xfs_mount *mp)
{
struct xfs_buf *bp = mp->m_sb_bp;
xfs_buf_lock(bp);
mp->m_sb_bp = NULL;
xfs_buf_relse(bp);
}
/*
* If the underlying (data/log/rt) device is readonly, there are some
* operations that cannot proceed.
*/
int
xfs_dev_is_read_only(
struct xfs_mount *mp,
char *message)
{
if (xfs_readonly_buftarg(mp->m_ddev_targp) ||
xfs_readonly_buftarg(mp->m_logdev_targp) ||
(mp->m_rtdev_targp && xfs_readonly_buftarg(mp->m_rtdev_targp))) {
xfs_notice(mp, "%s required on read-only device.", message);
xfs_notice(mp, "write access unavailable, cannot proceed.");
return -EROFS;
}
return 0;
}
/* Force the summary counters to be recalculated at next mount. */
void
xfs_force_summary_recalc(
struct xfs_mount *mp)
{
if (!xfs_has_lazysbcount(mp))
return;
xfs_fs_mark_sick(mp, XFS_SICK_FS_COUNTERS);
}
/*
* Enable a log incompat feature flag in the primary superblock. The caller
* cannot have any other transactions in progress.
*/
int
xfs_add_incompat_log_feature(
struct xfs_mount *mp,
uint32_t feature)
{
struct xfs_dsb *dsb;
int error;
ASSERT(hweight32(feature) == 1);
ASSERT(!(feature & XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN));
/*
* Force the log to disk and kick the background AIL thread to reduce
* the chances that the bwrite will stall waiting for the AIL to unpin
* the primary superblock buffer. This isn't a data integrity
* operation, so we don't need a synchronous push.
*/
error = xfs_log_force(mp, XFS_LOG_SYNC);
if (error)
return error;
xfs_ail_push_all(mp->m_ail);
/*
* Lock the primary superblock buffer to serialize all callers that
* are trying to set feature bits.
*/
xfs_buf_lock(mp->m_sb_bp);
xfs_buf_hold(mp->m_sb_bp);
if (xfs_is_shutdown(mp)) {
error = -EIO;
goto rele;
}
if (xfs_sb_has_incompat_log_feature(&mp->m_sb, feature))
goto rele;
/*
* Write the primary superblock to disk immediately, because we need
* the log_incompat bit to be set in the primary super now to protect
* the log items that we're going to commit later.
*/
dsb = mp->m_sb_bp->b_addr;
xfs_sb_to_disk(dsb, &mp->m_sb);
dsb->sb_features_log_incompat |= cpu_to_be32(feature);
error = xfs_bwrite(mp->m_sb_bp);
if (error)
goto shutdown;
/*
* Add the feature bits to the incore superblock before we unlock the
* buffer.
*/
xfs_sb_add_incompat_log_features(&mp->m_sb, feature);
xfs_buf_relse(mp->m_sb_bp);
/* Log the superblock to disk. */
return xfs_sync_sb(mp, false);
shutdown:
xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
rele:
xfs_buf_relse(mp->m_sb_bp);
return error;
}
/*
* Clear all the log incompat flags from the superblock.
*
* The caller cannot be in a transaction, must ensure that the log does not
* contain any log items protected by any log incompat bit, and must ensure
* that there are no other threads that depend on the state of the log incompat
* feature flags in the primary super.
*
* Returns true if the superblock is dirty.
*/
bool
xfs_clear_incompat_log_features(
struct xfs_mount *mp)
{
bool ret = false;
if (!xfs_has_crc(mp) ||
!xfs_sb_has_incompat_log_feature(&mp->m_sb,
XFS_SB_FEAT_INCOMPAT_LOG_ALL) ||
xfs_is_shutdown(mp))
return false;
/*
* Update the incore superblock. We synchronize on the primary super
* buffer lock to be consistent with the add function, though at least
* in theory this shouldn't be necessary.
*/
xfs_buf_lock(mp->m_sb_bp);
xfs_buf_hold(mp->m_sb_bp);
if (xfs_sb_has_incompat_log_feature(&mp->m_sb,
XFS_SB_FEAT_INCOMPAT_LOG_ALL)) {
xfs_info(mp, "Clearing log incompat feature flags.");
xfs_sb_remove_incompat_log_features(&mp->m_sb);
ret = true;
}
xfs_buf_relse(mp->m_sb_bp);
return ret;
}
/*
* Update the in-core delayed block counter.
*
* We prefer to update the counter without having to take a spinlock for every
* counter update (i.e. batching). Each change to delayed allocation
* reservations can change can easily exceed the default percpu counter
* batching, so we use a larger batch factor here.
*
* Note that we don't currently have any callers requiring fast summation
* (e.g. percpu_counter_read) so we can use a big batch value here.
*/
#define XFS_DELALLOC_BATCH (4096)
void
xfs_mod_delalloc(
struct xfs_mount *mp,
int64_t delta)
{
percpu_counter_add_batch(&mp->m_delalloc_blks, delta,
XFS_DELALLOC_BATCH);
}