linux-stable/fs/xfs/xfs_mount.c
Darrick J. Wong 525488520a xfs: rmap btree requires more reserved free space
Originally-From: Dave Chinner <dchinner@redhat.com>

The rmap btree is allocated from the AGFL, which means we have to
ensure ENOSPC is reported to userspace before we run out of free
space in each AG. The last allocation in an AG can cause a full
height rmap btree split, and that means we have to reserve at least
this many blocks *in each AG* to be placed on the AGFL at ENOSPC.
Update the various space calculation functions to handle this.

Also, because the macros are now executing conditional code and are
called quite frequently, convert them to functions that initialise
variables in the struct xfs_mount, use the new variables everywhere
and document the calculations better.

[darrick.wong@oracle.com: don't reserve blocks if !rmap]
[dchinner@redhat.com: update m_ag_max_usable after growfs]

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-08-03 11:38:24 +10:00

1330 lines
33 KiB
C

/*
* Copyright (c) 2000-2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#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_defer.h"
#include "xfs_da_format.h"
#include "xfs_da_btree.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_trace.h"
#include "xfs_icache.h"
#include "xfs_sysfs.h"
#include "xfs_rmap_btree.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;
if (mp->m_flags & XFS_MOUNT_NOUUID)
return 0;
if (uuid_is_nil(uuid)) {
xfs_warn(mp, "Filesystem has nil 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_nil(&xfs_uuid_table[i])) {
hole = i;
continue;
}
if (uuid_equal(uuid, &xfs_uuid_table[i]))
goto out_duplicate;
}
if (hole < 0) {
xfs_uuid_table = kmem_realloc(xfs_uuid_table,
(xfs_uuid_table_size + 1) * sizeof(*xfs_uuid_table),
KM_SLEEP);
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_nil(&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(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);
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 = 0;
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;
}
if (!first_initialised)
first_initialised = index;
pag = kmem_zalloc(sizeof(*pag), KM_MAYFAIL);
if (!pag)
goto out_unwind;
pag->pag_agno = index;
pag->pag_mount = mp;
spin_lock_init(&pag->pag_ici_lock);
mutex_init(&pag->pag_ici_reclaim_lock);
INIT_RADIX_TREE(&pag->pag_ici_root, GFP_ATOMIC);
spin_lock_init(&pag->pag_buf_lock);
pag->pag_buf_tree = RB_ROOT;
if (radix_tree_preload(GFP_NOFS))
goto out_unwind;
spin_lock(&mp->m_perag_lock);
if (radix_tree_insert(&mp->m_perag_tree, index, pag)) {
BUG();
spin_unlock(&mp->m_perag_lock);
radix_tree_preload_end();
error = -EEXIST;
goto out_unwind;
}
spin_unlock(&mp->m_perag_lock);
radix_tree_preload_end();
}
index = xfs_set_inode_alloc(mp, agcount);
if (maxagi)
*maxagi = index;
mp->m_ag_prealloc_blocks = xfs_prealloc_blocks(mp);
return 0;
out_unwind:
kmem_free(pag);
for (; index > first_initialised; index--) {
pag = radix_tree_delete(&mp->m_perag_tree, index);
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, XFS_BUF_TO_SBP(bp));
/*
* 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;
}
/*
* Update alignment values based on mount options and sb values
*/
STATIC int
xfs_update_alignment(xfs_mount_t *mp)
{
xfs_sb_t *sbp = &(mp->m_sb);
if (mp->m_dalign) {
/*
* 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)",
sbp->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 && (sbp->sb_agblocks % mp->m_dalign)) {
xfs_warn(mp,
"alignment check failed: sunit/swidth vs. agsize(%d)",
sbp->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, sbp->sb_blocksize);
return -EINVAL;
}
}
/*
* Update superblock with new values
* and log changes
*/
if (xfs_sb_version_hasdalign(sbp)) {
if (sbp->sb_unit != mp->m_dalign) {
sbp->sb_unit = mp->m_dalign;
mp->m_update_sb = true;
}
if (sbp->sb_width != mp->m_swidth) {
sbp->sb_width = mp->m_swidth;
mp->m_update_sb = true;
}
} else {
xfs_warn(mp,
"cannot change alignment: superblock does not support data alignment");
return -EINVAL;
}
} 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;
}
/*
* Set the maximum inode count for this filesystem
*/
STATIC void
xfs_set_maxicount(xfs_mount_t *mp)
{
xfs_sb_t *sbp = &(mp->m_sb);
__uint64_t icount;
if (sbp->sb_imax_pct) {
/*
* Make sure the maximum inode count is a multiple
* of the units we allocate inodes in.
*/
icount = sbp->sb_dblocks * sbp->sb_imax_pct;
do_div(icount, 100);
do_div(icount, mp->m_ialloc_blks);
mp->m_maxicount = (icount * mp->m_ialloc_blks) <<
sbp->sb_inopblog;
} else {
mp->m_maxicount = 0;
}
}
/*
* Set the default minimum read and write sizes unless
* already specified in a mount option.
* We use smaller I/O sizes when the file system
* is being used for NFS service (wsync mount option).
*/
STATIC void
xfs_set_rw_sizes(xfs_mount_t *mp)
{
xfs_sb_t *sbp = &(mp->m_sb);
int readio_log, writeio_log;
if (!(mp->m_flags & XFS_MOUNT_DFLT_IOSIZE)) {
if (mp->m_flags & XFS_MOUNT_WSYNC) {
readio_log = XFS_WSYNC_READIO_LOG;
writeio_log = XFS_WSYNC_WRITEIO_LOG;
} else {
readio_log = XFS_READIO_LOG_LARGE;
writeio_log = XFS_WRITEIO_LOG_LARGE;
}
} else {
readio_log = mp->m_readio_log;
writeio_log = mp->m_writeio_log;
}
if (sbp->sb_blocklog > readio_log) {
mp->m_readio_log = sbp->sb_blocklog;
} else {
mp->m_readio_log = readio_log;
}
mp->m_readio_blocks = 1 << (mp->m_readio_log - sbp->sb_blocklog);
if (sbp->sb_blocklog > writeio_log) {
mp->m_writeio_log = sbp->sb_blocklog;
} else {
mp->m_writeio_log = writeio_log;
}
mp->m_writeio_blocks = 1 << (mp->m_writeio_log - sbp->sb_blocklog);
}
/*
* 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);
}
}
/*
* Set whether we're using inode alignment.
*/
STATIC void
xfs_set_inoalignment(xfs_mount_t *mp)
{
if (xfs_sb_version_hasalign(&mp->m_sb) &&
mp->m_sb.sb_inoalignmt >=
XFS_B_TO_FSBT(mp, mp->m_inode_cluster_size))
mp->m_inoalign_mask = mp->m_sb.sb_inoalignmt - 1;
else
mp->m_inoalign_mask = 0;
/*
* If we are using stripe alignment, check whether
* the stripe unit is a multiple of the inode alignment
*/
if (mp->m_dalign && mp->m_inoalign_mask &&
!(mp->m_dalign & mp->m_inoalign_mask))
mp->m_sinoalign = mp->m_dalign;
else
mp->m_sinoalign = 0;
}
/*
* 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;
}
/*
* 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;
__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;
}
/*
* 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.
*/
error = xfs_update_alignment(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_ialloc_compute_maxlevels(mp);
xfs_rmapbt_compute_maxlevels(mp);
xfs_set_maxicount(mp);
/* enable fail_at_unmount as default */
mp->m_fail_unmount = 1;
error = xfs_sysfs_init(&mp->m_kobj, &xfs_mp_ktype, NULL, mp->m_fsname);
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_uuid_mount(mp);
if (error)
goto out_remove_error_sysfs;
/*
* Set the minimum read and write sizes
*/
xfs_set_rw_sizes(mp);
/* set the low space thresholds for dynamic preallocation */
xfs_set_low_space_thresholds(mp);
/*
* Set the inode cluster size.
* This may still be overridden by the file system
* block size if it is larger than the chosen cluster size.
*
* For v5 filesystems, scale the cluster size with the inode size to
* keep a constant ratio of inode per cluster buffer, but only if mkfs
* has set the inode alignment value appropriately for larger cluster
* sizes.
*/
mp->m_inode_cluster_size = XFS_INODE_BIG_CLUSTER_SIZE;
if (xfs_sb_version_hascrc(&mp->m_sb)) {
int new_size = mp->m_inode_cluster_size;
new_size *= mp->m_sb.sb_inodesize / XFS_DINODE_MIN_SIZE;
if (mp->m_sb.sb_inoalignmt >= XFS_B_TO_FSBT(mp, new_size))
mp->m_inode_cluster_size = new_size;
}
/*
* 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, mp->m_inode_cluster_size)) {
xfs_warn(mp,
"Sparse inode block alignment (%u) must match cluster size (%llu).",
mp->m_sb.sb_spino_align,
XFS_B_TO_FSBT(mp, mp->m_inode_cluster_size));
error = -EINVAL;
goto out_remove_uuid;
}
/*
* Set inode alignment fields
*/
xfs_set_inoalignment(mp);
/*
* 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.
*/
uuid_getnodeuniq(&sbp->sb_uuid, mp->m_fixedfsid);
mp->m_dmevmask = 0; /* not persistent; set after each mount */
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.
*/
spin_lock_init(&mp->m_perag_lock);
INIT_RADIX_TREE(&mp->m_perag_tree, GFP_ATOMIC);
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 (!sbp->sb_logblocks) {
xfs_warn(mp, "no log defined");
XFS_ERROR_REPORT("xfs_mountfs", XFS_ERRLEVEL_LOW, mp);
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;
}
/*
* 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.
*
* Hence 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 need to wait for recovery to finish before
* doing this.
*
* If the filesystem was cleanly unmounted, then we can trust the
* values in the superblock to be correct and we don't need to do
* anything here.
*
* If we are currently making the filesystem, the initialisation will
* fail as the perag data is in an undefined state.
*/
if (xfs_sb_version_haslazysbcount(&mp->m_sb) &&
!XFS_LAST_UNMOUNT_WAS_CLEAN(mp) &&
!mp->m_sb.sb_inprogress) {
error = xfs_initialize_perag_data(mp, sbp->sb_agcount);
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, 0, XFS_ILOCK_EXCL, &rip);
if (error) {
xfs_warn(mp, "failed to read root inode");
goto out_log_dealloc;
}
ASSERT(rip != NULL);
if (unlikely(!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);
XFS_ERROR_REPORT("xfs_mountfs_int(2)", XFS_ERRLEVEL_LOW,
mp);
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;
}
/*
* 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.");
}
return 0;
out_rtunmount:
xfs_rtunmount_inodes(mp);
out_rele_rip:
IRELE(rip);
cancel_delayed_work_sync(&mp->m_reclaim_work);
xfs_reclaim_inodes(mp, SYNC_WAIT);
out_log_dealloc:
mp->m_flags |= XFS_MOUNT_UNMOUNTING;
xfs_log_mount_cancel(mp);
out_fail_wait:
if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp)
xfs_wait_buftarg(mp->m_logdev_targp);
xfs_wait_buftarg(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_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;
cancel_delayed_work_sync(&mp->m_eofblocks_work);
xfs_qm_unmount_quotas(mp);
xfs_rtunmount_inodes(mp);
IRELE(mp->m_rootip);
/*
* We can potentially deadlock here if we have an inode cluster
* that has been freed has its buffer still pinned in memory because
* the transaction is still sitting in a iclog. The stale inodes
* on that buffer will have their flush locks held until the
* transaction hits the disk and the callbacks run. the inode
* flush takes the flush lock unconditionally and with nothing to
* push out the iclog we will never get that unlocked. hence we
* need to force the log first.
*/
xfs_log_force(mp, XFS_LOG_SYNC);
/*
* We now need to tell the world we are unmounting. This will allow
* us to detect that the filesystem is going away and we should error
* out anything that we have been retrying in the background. This will
* prevent neverending retries in AIL pushing from hanging the unmount.
*/
mp->m_flags |= XFS_MOUNT_UNMOUNTING;
/*
* Flush all pending changes from the AIL.
*/
xfs_ail_push_all_sync(mp->m_ail);
/*
* And reclaim all inodes. At this point there should be no dirty
* inodes and none should be pinned or locked, but use synchronous
* reclaim just to be sure. We can stop background inode reclaim
* here as well if it is still running.
*/
cancel_delayed_work_sync(&mp->m_reclaim_work);
xfs_reclaim_inodes(mp, SYNC_WAIT);
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.");
error = xfs_log_sbcount(mp);
if (error)
xfs_warn(mp, "Unable to update superblock counters. "
"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, 0);
#endif
xfs_free_perag(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;
}
/*
* xfs_log_sbcount
*
* Sync the superblock counters to disk.
*
* Note this code can be called during the process of freezing, so we use the
* transaction allocator that does not block when the transaction subsystem is
* in its frozen state.
*/
int
xfs_log_sbcount(xfs_mount_t *mp)
{
/* allow this to proceed during the freeze sequence... */
if (!xfs_fs_writable(mp, SB_FREEZE_COMPLETE))
return 0;
/*
* we don't need to do this if we are updating the superblock
* counters on every modification.
*/
if (!xfs_sb_version_haslazysbcount(&mp->m_sb))
return 0;
return xfs_sync_sb(mp, true);
}
/*
* Deltas for the inode count are +/-64, hence we use a large batch size
* of 128 so we don't need to take the counter lock on every update.
*/
#define XFS_ICOUNT_BATCH 128
int
xfs_mod_icount(
struct xfs_mount *mp,
int64_t delta)
{
__percpu_counter_add(&mp->m_icount, delta, XFS_ICOUNT_BATCH);
if (__percpu_counter_compare(&mp->m_icount, 0, XFS_ICOUNT_BATCH) < 0) {
ASSERT(0);
percpu_counter_add(&mp->m_icount, -delta);
return -EINVAL;
}
return 0;
}
int
xfs_mod_ifree(
struct xfs_mount *mp,
int64_t delta)
{
percpu_counter_add(&mp->m_ifree, delta);
if (percpu_counter_compare(&mp->m_ifree, 0) < 0) {
ASSERT(0);
percpu_counter_add(&mp->m_ifree, -delta);
return -EINVAL;
}
return 0;
}
/*
* 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;
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;
__percpu_counter_add(&mp->m_fdblocks, delta, batch);
if (__percpu_counter_compare(&mp->m_fdblocks, mp->m_alloc_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;
}
printk_once(KERN_WARNING
"Filesystem \"%s\": reserve blocks depleted! "
"Consider increasing reserve pool size.",
mp->m_fsname);
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;
}
/*
* xfs_getsb() is called to obtain the buffer for the superblock.
* The buffer is returned locked and read in from disk.
* The buffer should be released with a call to xfs_brelse().
*
* If the flags parameter is BUF_TRYLOCK, then we'll only return
* the superblock buffer if it can be locked without sleeping.
* If it can't then we'll return NULL.
*/
struct xfs_buf *
xfs_getsb(
struct xfs_mount *mp,
int flags)
{
struct xfs_buf *bp = mp->m_sb_bp;
if (!xfs_buf_trylock(bp)) {
if (flags & XBF_TRYLOCK)
return NULL;
xfs_buf_lock(bp);
}
xfs_buf_hold(bp);
ASSERT(bp->b_flags & XBF_DONE);
return bp;
}
/*
* 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;
}