linux/fs/xfs/xfs_mount.c
Brian Foster fd43cf600c xfs: set aside allocation btree blocks from block reservation
The blocks used for allocation btrees (bnobt and countbt) are
technically considered free space. This is because as free space is
used, allocbt blocks are removed and naturally become available for
traditional allocation. However, this means that a significant
portion of free space may consist of in-use btree blocks if free
space is severely fragmented.

On large filesystems with large perag reservations, this can lead to
a rare but nasty condition where a significant amount of physical
free space is available, but the majority of actual usable blocks
consist of in-use allocbt blocks. We have a record of a (~12TB, 32
AG) filesystem with multiple AGs in a state with ~2.5GB or so free
blocks tracked across ~300 total allocbt blocks, but effectively at
100% full because the the free space is entirely consumed by
refcountbt perag reservation.

Such a large perag reservation is by design on large filesystems.
The problem is that because the free space is so fragmented, this AG
contributes the 300 or so allocbt blocks to the global counters as
free space. If this pattern repeats across enough AGs, the
filesystem lands in a state where global block reservation can
outrun physical block availability. For example, a streaming
buffered write on the affected filesystem continues to allow delayed
allocation beyond the point where writeback starts to fail due to
physical block allocation failures. The expected behavior is for the
delalloc block reservation to fail gracefully with -ENOSPC before
physical block allocation failure is a possibility.

To address this problem, set aside in-use allocbt blocks at
reservation time and thus ensure they cannot be reserved until truly
available for physical allocation. This allows alloc btree metadata
to continue to reside in free space, but dynamically adjusts
reservation availability based on internal state. Note that the
logic requires that the allocbt counter is fully populated at
reservation time before it is fully effective. We currently rely on
the mount time AGF scan in the perag reservation initialization code
for this dependency on filesystems where it's most important (i.e.
with active perag reservations).

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-29 07:45:44 -07:00

1355 lines
35 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"
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 (mp->m_flags & XFS_MOUNT_NOUUID)
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 (mp->m_flags & XFS_MOUNT_NOUUID)
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);
}
STATIC void
__xfs_free_perag(
struct rcu_head *head)
{
struct xfs_perag *pag = container_of(head, struct xfs_perag, rcu_head);
ASSERT(!delayed_work_pending(&pag->pag_blockgc_work));
ASSERT(atomic_read(&pag->pag_ref) == 0);
kmem_free(pag);
}
/*
* Free up the per-ag resources associated with the mount structure.
*/
STATIC void
xfs_free_perag(
xfs_mount_t *mp)
{
xfs_agnumber_t agno;
struct xfs_perag *pag;
for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
spin_lock(&mp->m_perag_lock);
pag = radix_tree_delete(&mp->m_perag_tree, agno);
spin_unlock(&mp->m_perag_lock);
ASSERT(pag);
ASSERT(atomic_read(&pag->pag_ref) == 0);
cancel_delayed_work_sync(&pag->pag_blockgc_work);
xfs_iunlink_destroy(pag);
xfs_buf_hash_destroy(pag);
call_rcu(&pag->rcu_head, __xfs_free_perag);
}
}
/*
* 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;
}
int
xfs_initialize_perag(
xfs_mount_t *mp,
xfs_agnumber_t agcount,
xfs_agnumber_t *maxagi)
{
xfs_agnumber_t index;
xfs_agnumber_t first_initialised = NULLAGNUMBER;
xfs_perag_t *pag;
int error = -ENOMEM;
/*
* Walk the current per-ag tree so we don't try to initialise AGs
* that already exist (growfs case). Allocate and insert all the
* AGs we don't find ready for initialisation.
*/
for (index = 0; index < agcount; index++) {
pag = xfs_perag_get(mp, index);
if (pag) {
xfs_perag_put(pag);
continue;
}
pag = kmem_zalloc(sizeof(*pag), KM_MAYFAIL);
if (!pag) {
error = -ENOMEM;
goto out_unwind_new_pags;
}
pag->pag_agno = index;
pag->pag_mount = mp;
spin_lock_init(&pag->pag_ici_lock);
INIT_DELAYED_WORK(&pag->pag_blockgc_work, xfs_blockgc_worker);
INIT_RADIX_TREE(&pag->pag_ici_root, GFP_ATOMIC);
error = xfs_buf_hash_init(pag);
if (error)
goto out_free_pag;
init_waitqueue_head(&pag->pagb_wait);
spin_lock_init(&pag->pagb_lock);
pag->pagb_count = 0;
pag->pagb_tree = RB_ROOT;
error = radix_tree_preload(GFP_NOFS);
if (error)
goto out_hash_destroy;
spin_lock(&mp->m_perag_lock);
if (radix_tree_insert(&mp->m_perag_tree, index, pag)) {
WARN_ON_ONCE(1);
spin_unlock(&mp->m_perag_lock);
radix_tree_preload_end();
error = -EEXIST;
goto out_hash_destroy;
}
spin_unlock(&mp->m_perag_lock);
radix_tree_preload_end();
/* first new pag is fully initialized */
if (first_initialised == NULLAGNUMBER)
first_initialised = index;
error = xfs_iunlink_init(pag);
if (error)
goto out_hash_destroy;
spin_lock_init(&pag->pag_state_lock);
}
index = xfs_set_inode_alloc(mp, agcount);
if (maxagi)
*maxagi = index;
mp->m_ag_prealloc_blocks = xfs_prealloc_blocks(mp);
return 0;
out_hash_destroy:
xfs_buf_hash_destroy(pag);
out_free_pag:
kmem_free(pag);
out_unwind_new_pags:
/* unwind any prior newly initialized pags */
for (index = first_initialised; index < agcount; index++) {
pag = radix_tree_delete(&mp->m_perag_tree, index);
if (!pag)
break;
xfs_buf_hash_destroy(pag);
xfs_iunlink_destroy(pag);
kmem_free(pag);
}
return error;
}
/*
* 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;
}
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_sb_version_hasdalign(&mp->m_sb)) {
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 ((mp->m_flags & XFS_MOUNT_NOALIGN) != XFS_MOUNT_NOALIGN &&
xfs_sb_version_hasdalign(&mp->m_sb)) {
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)
{
int i;
for (i = 0; i < XFS_LOWSP_MAX; i++) {
uint64_t space = mp->m_sb.sb_dblocks;
do_div(space, 100);
mp->m_low_space[i] = space * (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_LAST_UNMOUNT_WAS_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_sb_version_haslazysbcount(&mp->m_sb) ||
XFS_LAST_UNMOUNT_WAS_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.
*
* 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);
mp->m_flags |= XFS_MOUNT_UNMOUNTING;
xfs_ail_push_all_sync(mp->m_ail);
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);
}
/*
* 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;
/*
* Re-check for ATTR2 in case it was found in bad_features2
* slot.
*/
if (xfs_sb_version_hasattr2(&mp->m_sb) &&
!(mp->m_flags & XFS_MOUNT_NOATTR2))
mp->m_flags |= XFS_MOUNT_ATTR2;
}
if (xfs_sb_version_hasattr2(&mp->m_sb) &&
(mp->m_flags & XFS_MOUNT_NOATTR2)) {
xfs_sb_version_removeattr2(&mp->m_sb);
mp->m_update_sb = true;
/* update sb_versionnum for the clearing of the morebits */
if (!sbp->sb_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_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);
/*
* 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_sb_version_hassparseinodes(&mp->m_sb) &&
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;
}
/*
* 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_fail_wait;
}
/* Make sure the summary counts are ok. */
error = xfs_check_summary_counts(mp);
if (error)
goto out_log_dealloc;
/*
* 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 && !(mp->m_flags & XFS_MOUNT_RDONLY)) {
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_RUNNING(mp)) {
error = xfs_qm_newmount(mp, &quotamount, &quotaflags);
if (error)
goto out_rtunmount;
} else {
ASSERT(!XFS_IS_QUOTA_ON(mp));
/*
* 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.
*/
error = xfs_log_mount_finish(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 ((mp->m_flags & (XFS_MOUNT_RDONLY|XFS_MOUNT_NORECOVERY)) ==
XFS_MOUNT_RDONLY) {
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 (!(mp->m_flags & XFS_MOUNT_RDONLY)) {
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.");
/* Recover any CoW blocks that never got remapped. */
error = xfs_reflink_recover_cow(mp);
if (error) {
xfs_err(mp,
"Error %d recovering leftover CoW allocations.", error);
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
goto out_quota;
}
/* 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);
out_quota:
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);
/*
* 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_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;
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
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_FORCED_SHUTDOWN(mp) || (mp->m_flags & XFS_MOUNT_RDONLY))
return false;
return true;
}
/*
* Deltas for the block count can vary from 1 to very large, but lock contention
* only occurs on frequent small block count updates such as in the delayed
* allocation path for buffered writes (page a time updates). Hence we set
* a large batch count (1024) to minimise global counter updates except when
* we get near to ENOSPC and we have to be very accurate with our updates.
*/
#define XFS_FDBLOCKS_BATCH 1024
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_sb_version_haslazysbcount(&mp->m_sb))
return;
xfs_fs_mark_sick(mp, XFS_SICK_FS_COUNTERS);
}
/*
* 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);
}