linux-stable/fs/xfs/xfs_trans.c
Darrick J. Wong 47a6df7cd3 xfs: shut down filesystem if we xfs_trans_cancel with deferred work items
While debugging some very strange rmap corruption reports in connection
with the online directory repair code.  I root-caused the error to the
following incorrect sequence:

<start repair transaction>
<expand directory, causing a deferred rmap to be queued>
<roll transaction>
<cancel transaction>

Obviously, we should have committed the transaction instead of
cancelling it.  Thinking more broadly, however, xfs_trans_cancel should
have warned us that we were throwing away work item that we already
committed to performing.  This is not correct, and we need to shut down
the filesystem.

Change xfs_trans_cancel to complain in the loudest manner if we're
cancelling any transaction with deferred work items attached.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2021-12-21 09:49:41 -08:00

1212 lines
32 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
* Copyright (C) 2010 Red Hat, 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_mount.h"
#include "xfs_extent_busy.h"
#include "xfs_quota.h"
#include "xfs_trans.h"
#include "xfs_trans_priv.h"
#include "xfs_log.h"
#include "xfs_log_priv.h"
#include "xfs_trace.h"
#include "xfs_error.h"
#include "xfs_defer.h"
#include "xfs_inode.h"
#include "xfs_dquot_item.h"
#include "xfs_dquot.h"
#include "xfs_icache.h"
struct kmem_cache *xfs_trans_cache;
#if defined(CONFIG_TRACEPOINTS)
static void
xfs_trans_trace_reservations(
struct xfs_mount *mp)
{
struct xfs_trans_res resv;
struct xfs_trans_res *res;
struct xfs_trans_res *end_res;
int i;
res = (struct xfs_trans_res *)M_RES(mp);
end_res = (struct xfs_trans_res *)(M_RES(mp) + 1);
for (i = 0; res < end_res; i++, res++)
trace_xfs_trans_resv_calc(mp, i, res);
xfs_log_get_max_trans_res(mp, &resv);
trace_xfs_trans_resv_calc(mp, -1, &resv);
}
#else
# define xfs_trans_trace_reservations(mp)
#endif
/*
* Initialize the precomputed transaction reservation values
* in the mount structure.
*/
void
xfs_trans_init(
struct xfs_mount *mp)
{
xfs_trans_resv_calc(mp, M_RES(mp));
xfs_trans_trace_reservations(mp);
}
/*
* Free the transaction structure. If there is more clean up
* to do when the structure is freed, add it here.
*/
STATIC void
xfs_trans_free(
struct xfs_trans *tp)
{
xfs_extent_busy_sort(&tp->t_busy);
xfs_extent_busy_clear(tp->t_mountp, &tp->t_busy, false);
trace_xfs_trans_free(tp, _RET_IP_);
xfs_trans_clear_context(tp);
if (!(tp->t_flags & XFS_TRANS_NO_WRITECOUNT))
sb_end_intwrite(tp->t_mountp->m_super);
xfs_trans_free_dqinfo(tp);
kmem_cache_free(xfs_trans_cache, tp);
}
/*
* This is called to create a new transaction which will share the
* permanent log reservation of the given transaction. The remaining
* unused block and rt extent reservations are also inherited. This
* implies that the original transaction is no longer allowed to allocate
* blocks. Locks and log items, however, are no inherited. They must
* be added to the new transaction explicitly.
*/
STATIC struct xfs_trans *
xfs_trans_dup(
struct xfs_trans *tp)
{
struct xfs_trans *ntp;
trace_xfs_trans_dup(tp, _RET_IP_);
ntp = kmem_cache_zalloc(xfs_trans_cache, GFP_KERNEL | __GFP_NOFAIL);
/*
* Initialize the new transaction structure.
*/
ntp->t_magic = XFS_TRANS_HEADER_MAGIC;
ntp->t_mountp = tp->t_mountp;
INIT_LIST_HEAD(&ntp->t_items);
INIT_LIST_HEAD(&ntp->t_busy);
INIT_LIST_HEAD(&ntp->t_dfops);
ntp->t_firstblock = NULLFSBLOCK;
ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
ASSERT(tp->t_ticket != NULL);
ntp->t_flags = XFS_TRANS_PERM_LOG_RES |
(tp->t_flags & XFS_TRANS_RESERVE) |
(tp->t_flags & XFS_TRANS_NO_WRITECOUNT) |
(tp->t_flags & XFS_TRANS_RES_FDBLKS);
/* We gave our writer reference to the new transaction */
tp->t_flags |= XFS_TRANS_NO_WRITECOUNT;
ntp->t_ticket = xfs_log_ticket_get(tp->t_ticket);
ASSERT(tp->t_blk_res >= tp->t_blk_res_used);
ntp->t_blk_res = tp->t_blk_res - tp->t_blk_res_used;
tp->t_blk_res = tp->t_blk_res_used;
ntp->t_rtx_res = tp->t_rtx_res - tp->t_rtx_res_used;
tp->t_rtx_res = tp->t_rtx_res_used;
xfs_trans_switch_context(tp, ntp);
/* move deferred ops over to the new tp */
xfs_defer_move(ntp, tp);
xfs_trans_dup_dqinfo(tp, ntp);
return ntp;
}
/*
* This is called to reserve free disk blocks and log space for the
* given transaction. This must be done before allocating any resources
* within the transaction.
*
* This will return ENOSPC if there are not enough blocks available.
* It will sleep waiting for available log space.
* The only valid value for the flags parameter is XFS_RES_LOG_PERM, which
* is used by long running transactions. If any one of the reservations
* fails then they will all be backed out.
*
* This does not do quota reservations. That typically is done by the
* caller afterwards.
*/
static int
xfs_trans_reserve(
struct xfs_trans *tp,
struct xfs_trans_res *resp,
uint blocks,
uint rtextents)
{
struct xfs_mount *mp = tp->t_mountp;
int error = 0;
bool rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
/*
* Attempt to reserve the needed disk blocks by decrementing
* the number needed from the number available. This will
* fail if the count would go below zero.
*/
if (blocks > 0) {
error = xfs_mod_fdblocks(mp, -((int64_t)blocks), rsvd);
if (error != 0)
return -ENOSPC;
tp->t_blk_res += blocks;
}
/*
* Reserve the log space needed for this transaction.
*/
if (resp->tr_logres > 0) {
bool permanent = false;
ASSERT(tp->t_log_res == 0 ||
tp->t_log_res == resp->tr_logres);
ASSERT(tp->t_log_count == 0 ||
tp->t_log_count == resp->tr_logcount);
if (resp->tr_logflags & XFS_TRANS_PERM_LOG_RES) {
tp->t_flags |= XFS_TRANS_PERM_LOG_RES;
permanent = true;
} else {
ASSERT(tp->t_ticket == NULL);
ASSERT(!(tp->t_flags & XFS_TRANS_PERM_LOG_RES));
}
if (tp->t_ticket != NULL) {
ASSERT(resp->tr_logflags & XFS_TRANS_PERM_LOG_RES);
error = xfs_log_regrant(mp, tp->t_ticket);
} else {
error = xfs_log_reserve(mp,
resp->tr_logres,
resp->tr_logcount,
&tp->t_ticket, XFS_TRANSACTION,
permanent);
}
if (error)
goto undo_blocks;
tp->t_log_res = resp->tr_logres;
tp->t_log_count = resp->tr_logcount;
}
/*
* Attempt to reserve the needed realtime extents by decrementing
* the number needed from the number available. This will
* fail if the count would go below zero.
*/
if (rtextents > 0) {
error = xfs_mod_frextents(mp, -((int64_t)rtextents));
if (error) {
error = -ENOSPC;
goto undo_log;
}
tp->t_rtx_res += rtextents;
}
return 0;
/*
* Error cases jump to one of these labels to undo any
* reservations which have already been performed.
*/
undo_log:
if (resp->tr_logres > 0) {
xfs_log_ticket_ungrant(mp->m_log, tp->t_ticket);
tp->t_ticket = NULL;
tp->t_log_res = 0;
tp->t_flags &= ~XFS_TRANS_PERM_LOG_RES;
}
undo_blocks:
if (blocks > 0) {
xfs_mod_fdblocks(mp, (int64_t)blocks, rsvd);
tp->t_blk_res = 0;
}
return error;
}
int
xfs_trans_alloc(
struct xfs_mount *mp,
struct xfs_trans_res *resp,
uint blocks,
uint rtextents,
uint flags,
struct xfs_trans **tpp)
{
struct xfs_trans *tp;
bool want_retry = true;
int error;
/*
* Allocate the handle before we do our freeze accounting and setting up
* GFP_NOFS allocation context so that we avoid lockdep false positives
* by doing GFP_KERNEL allocations inside sb_start_intwrite().
*/
retry:
tp = kmem_cache_zalloc(xfs_trans_cache, GFP_KERNEL | __GFP_NOFAIL);
if (!(flags & XFS_TRANS_NO_WRITECOUNT))
sb_start_intwrite(mp->m_super);
xfs_trans_set_context(tp);
/*
* Zero-reservation ("empty") transactions can't modify anything, so
* they're allowed to run while we're frozen.
*/
WARN_ON(resp->tr_logres > 0 &&
mp->m_super->s_writers.frozen == SB_FREEZE_COMPLETE);
ASSERT(!(flags & XFS_TRANS_RES_FDBLKS) ||
xfs_has_lazysbcount(mp));
tp->t_magic = XFS_TRANS_HEADER_MAGIC;
tp->t_flags = flags;
tp->t_mountp = mp;
INIT_LIST_HEAD(&tp->t_items);
INIT_LIST_HEAD(&tp->t_busy);
INIT_LIST_HEAD(&tp->t_dfops);
tp->t_firstblock = NULLFSBLOCK;
error = xfs_trans_reserve(tp, resp, blocks, rtextents);
if (error == -ENOSPC && want_retry) {
xfs_trans_cancel(tp);
/*
* We weren't able to reserve enough space for the transaction.
* Flush the other speculative space allocations to free space.
* Do not perform a synchronous scan because callers can hold
* other locks.
*/
xfs_blockgc_flush_all(mp);
want_retry = false;
goto retry;
}
if (error) {
xfs_trans_cancel(tp);
return error;
}
trace_xfs_trans_alloc(tp, _RET_IP_);
*tpp = tp;
return 0;
}
/*
* Create an empty transaction with no reservation. This is a defensive
* mechanism for routines that query metadata without actually modifying them --
* if the metadata being queried is somehow cross-linked (think a btree block
* pointer that points higher in the tree), we risk deadlock. However, blocks
* grabbed as part of a transaction can be re-grabbed. The verifiers will
* notice the corrupt block and the operation will fail back to userspace
* without deadlocking.
*
* Note the zero-length reservation; this transaction MUST be cancelled without
* any dirty data.
*
* Callers should obtain freeze protection to avoid a conflict with fs freezing
* where we can be grabbing buffers at the same time that freeze is trying to
* drain the buffer LRU list.
*/
int
xfs_trans_alloc_empty(
struct xfs_mount *mp,
struct xfs_trans **tpp)
{
struct xfs_trans_res resv = {0};
return xfs_trans_alloc(mp, &resv, 0, 0, XFS_TRANS_NO_WRITECOUNT, tpp);
}
/*
* Record the indicated change to the given field for application
* to the file system's superblock when the transaction commits.
* For now, just store the change in the transaction structure.
*
* Mark the transaction structure to indicate that the superblock
* needs to be updated before committing.
*
* Because we may not be keeping track of allocated/free inodes and
* used filesystem blocks in the superblock, we do not mark the
* superblock dirty in this transaction if we modify these fields.
* We still need to update the transaction deltas so that they get
* applied to the incore superblock, but we don't want them to
* cause the superblock to get locked and logged if these are the
* only fields in the superblock that the transaction modifies.
*/
void
xfs_trans_mod_sb(
xfs_trans_t *tp,
uint field,
int64_t delta)
{
uint32_t flags = (XFS_TRANS_DIRTY|XFS_TRANS_SB_DIRTY);
xfs_mount_t *mp = tp->t_mountp;
switch (field) {
case XFS_TRANS_SB_ICOUNT:
tp->t_icount_delta += delta;
if (xfs_has_lazysbcount(mp))
flags &= ~XFS_TRANS_SB_DIRTY;
break;
case XFS_TRANS_SB_IFREE:
tp->t_ifree_delta += delta;
if (xfs_has_lazysbcount(mp))
flags &= ~XFS_TRANS_SB_DIRTY;
break;
case XFS_TRANS_SB_FDBLOCKS:
/*
* Track the number of blocks allocated in the transaction.
* Make sure it does not exceed the number reserved. If so,
* shutdown as this can lead to accounting inconsistency.
*/
if (delta < 0) {
tp->t_blk_res_used += (uint)-delta;
if (tp->t_blk_res_used > tp->t_blk_res)
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
} else if (delta > 0 && (tp->t_flags & XFS_TRANS_RES_FDBLKS)) {
int64_t blkres_delta;
/*
* Return freed blocks directly to the reservation
* instead of the global pool, being careful not to
* overflow the trans counter. This is used to preserve
* reservation across chains of transaction rolls that
* repeatedly free and allocate blocks.
*/
blkres_delta = min_t(int64_t, delta,
UINT_MAX - tp->t_blk_res);
tp->t_blk_res += blkres_delta;
delta -= blkres_delta;
}
tp->t_fdblocks_delta += delta;
if (xfs_has_lazysbcount(mp))
flags &= ~XFS_TRANS_SB_DIRTY;
break;
case XFS_TRANS_SB_RES_FDBLOCKS:
/*
* The allocation has already been applied to the
* in-core superblock's counter. This should only
* be applied to the on-disk superblock.
*/
tp->t_res_fdblocks_delta += delta;
if (xfs_has_lazysbcount(mp))
flags &= ~XFS_TRANS_SB_DIRTY;
break;
case XFS_TRANS_SB_FREXTENTS:
/*
* Track the number of blocks allocated in the
* transaction. Make sure it does not exceed the
* number reserved.
*/
if (delta < 0) {
tp->t_rtx_res_used += (uint)-delta;
ASSERT(tp->t_rtx_res_used <= tp->t_rtx_res);
}
tp->t_frextents_delta += delta;
break;
case XFS_TRANS_SB_RES_FREXTENTS:
/*
* The allocation has already been applied to the
* in-core superblock's counter. This should only
* be applied to the on-disk superblock.
*/
ASSERT(delta < 0);
tp->t_res_frextents_delta += delta;
break;
case XFS_TRANS_SB_DBLOCKS:
tp->t_dblocks_delta += delta;
break;
case XFS_TRANS_SB_AGCOUNT:
ASSERT(delta > 0);
tp->t_agcount_delta += delta;
break;
case XFS_TRANS_SB_IMAXPCT:
tp->t_imaxpct_delta += delta;
break;
case XFS_TRANS_SB_REXTSIZE:
tp->t_rextsize_delta += delta;
break;
case XFS_TRANS_SB_RBMBLOCKS:
tp->t_rbmblocks_delta += delta;
break;
case XFS_TRANS_SB_RBLOCKS:
tp->t_rblocks_delta += delta;
break;
case XFS_TRANS_SB_REXTENTS:
tp->t_rextents_delta += delta;
break;
case XFS_TRANS_SB_REXTSLOG:
tp->t_rextslog_delta += delta;
break;
default:
ASSERT(0);
return;
}
tp->t_flags |= flags;
}
/*
* xfs_trans_apply_sb_deltas() is called from the commit code
* to bring the superblock buffer into the current transaction
* and modify it as requested by earlier calls to xfs_trans_mod_sb().
*
* For now we just look at each field allowed to change and change
* it if necessary.
*/
STATIC void
xfs_trans_apply_sb_deltas(
xfs_trans_t *tp)
{
struct xfs_dsb *sbp;
struct xfs_buf *bp;
int whole = 0;
bp = xfs_trans_getsb(tp);
sbp = bp->b_addr;
/*
* Only update the superblock counters if we are logging them
*/
if (!xfs_has_lazysbcount((tp->t_mountp))) {
if (tp->t_icount_delta)
be64_add_cpu(&sbp->sb_icount, tp->t_icount_delta);
if (tp->t_ifree_delta)
be64_add_cpu(&sbp->sb_ifree, tp->t_ifree_delta);
if (tp->t_fdblocks_delta)
be64_add_cpu(&sbp->sb_fdblocks, tp->t_fdblocks_delta);
if (tp->t_res_fdblocks_delta)
be64_add_cpu(&sbp->sb_fdblocks, tp->t_res_fdblocks_delta);
}
if (tp->t_frextents_delta)
be64_add_cpu(&sbp->sb_frextents, tp->t_frextents_delta);
if (tp->t_res_frextents_delta)
be64_add_cpu(&sbp->sb_frextents, tp->t_res_frextents_delta);
if (tp->t_dblocks_delta) {
be64_add_cpu(&sbp->sb_dblocks, tp->t_dblocks_delta);
whole = 1;
}
if (tp->t_agcount_delta) {
be32_add_cpu(&sbp->sb_agcount, tp->t_agcount_delta);
whole = 1;
}
if (tp->t_imaxpct_delta) {
sbp->sb_imax_pct += tp->t_imaxpct_delta;
whole = 1;
}
if (tp->t_rextsize_delta) {
be32_add_cpu(&sbp->sb_rextsize, tp->t_rextsize_delta);
whole = 1;
}
if (tp->t_rbmblocks_delta) {
be32_add_cpu(&sbp->sb_rbmblocks, tp->t_rbmblocks_delta);
whole = 1;
}
if (tp->t_rblocks_delta) {
be64_add_cpu(&sbp->sb_rblocks, tp->t_rblocks_delta);
whole = 1;
}
if (tp->t_rextents_delta) {
be64_add_cpu(&sbp->sb_rextents, tp->t_rextents_delta);
whole = 1;
}
if (tp->t_rextslog_delta) {
sbp->sb_rextslog += tp->t_rextslog_delta;
whole = 1;
}
xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF);
if (whole)
/*
* Log the whole thing, the fields are noncontiguous.
*/
xfs_trans_log_buf(tp, bp, 0, sizeof(struct xfs_dsb) - 1);
else
/*
* Since all the modifiable fields are contiguous, we
* can get away with this.
*/
xfs_trans_log_buf(tp, bp, offsetof(struct xfs_dsb, sb_icount),
offsetof(struct xfs_dsb, sb_frextents) +
sizeof(sbp->sb_frextents) - 1);
}
/*
* xfs_trans_unreserve_and_mod_sb() is called to release unused reservations and
* apply superblock counter changes to the in-core superblock. The
* t_res_fdblocks_delta and t_res_frextents_delta fields are explicitly NOT
* applied to the in-core superblock. The idea is that that has already been
* done.
*
* If we are not logging superblock counters, then the inode allocated/free and
* used block counts are not updated in the on disk superblock. In this case,
* XFS_TRANS_SB_DIRTY will not be set when the transaction is updated but we
* still need to update the incore superblock with the changes.
*
* 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
void
xfs_trans_unreserve_and_mod_sb(
struct xfs_trans *tp)
{
struct xfs_mount *mp = tp->t_mountp;
bool rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
int64_t blkdelta = 0;
int64_t rtxdelta = 0;
int64_t idelta = 0;
int64_t ifreedelta = 0;
int error;
/* calculate deltas */
if (tp->t_blk_res > 0)
blkdelta = tp->t_blk_res;
if ((tp->t_fdblocks_delta != 0) &&
(xfs_has_lazysbcount(mp) ||
(tp->t_flags & XFS_TRANS_SB_DIRTY)))
blkdelta += tp->t_fdblocks_delta;
if (tp->t_rtx_res > 0)
rtxdelta = tp->t_rtx_res;
if ((tp->t_frextents_delta != 0) &&
(tp->t_flags & XFS_TRANS_SB_DIRTY))
rtxdelta += tp->t_frextents_delta;
if (xfs_has_lazysbcount(mp) ||
(tp->t_flags & XFS_TRANS_SB_DIRTY)) {
idelta = tp->t_icount_delta;
ifreedelta = tp->t_ifree_delta;
}
/* apply the per-cpu counters */
if (blkdelta) {
error = xfs_mod_fdblocks(mp, blkdelta, rsvd);
ASSERT(!error);
}
if (idelta)
percpu_counter_add_batch(&mp->m_icount, idelta,
XFS_ICOUNT_BATCH);
if (ifreedelta)
percpu_counter_add(&mp->m_ifree, ifreedelta);
if (rtxdelta == 0 && !(tp->t_flags & XFS_TRANS_SB_DIRTY))
return;
/* apply remaining deltas */
spin_lock(&mp->m_sb_lock);
mp->m_sb.sb_fdblocks += tp->t_fdblocks_delta + tp->t_res_fdblocks_delta;
mp->m_sb.sb_icount += idelta;
mp->m_sb.sb_ifree += ifreedelta;
mp->m_sb.sb_frextents += rtxdelta;
mp->m_sb.sb_dblocks += tp->t_dblocks_delta;
mp->m_sb.sb_agcount += tp->t_agcount_delta;
mp->m_sb.sb_imax_pct += tp->t_imaxpct_delta;
mp->m_sb.sb_rextsize += tp->t_rextsize_delta;
mp->m_sb.sb_rbmblocks += tp->t_rbmblocks_delta;
mp->m_sb.sb_rblocks += tp->t_rblocks_delta;
mp->m_sb.sb_rextents += tp->t_rextents_delta;
mp->m_sb.sb_rextslog += tp->t_rextslog_delta;
spin_unlock(&mp->m_sb_lock);
/*
* Debug checks outside of the spinlock so they don't lock up the
* machine if they fail.
*/
ASSERT(mp->m_sb.sb_imax_pct >= 0);
ASSERT(mp->m_sb.sb_rextslog >= 0);
return;
}
/* Add the given log item to the transaction's list of log items. */
void
xfs_trans_add_item(
struct xfs_trans *tp,
struct xfs_log_item *lip)
{
ASSERT(lip->li_mountp == tp->t_mountp);
ASSERT(lip->li_ailp == tp->t_mountp->m_ail);
ASSERT(list_empty(&lip->li_trans));
ASSERT(!test_bit(XFS_LI_DIRTY, &lip->li_flags));
list_add_tail(&lip->li_trans, &tp->t_items);
trace_xfs_trans_add_item(tp, _RET_IP_);
}
/*
* Unlink the log item from the transaction. the log item is no longer
* considered dirty in this transaction, as the linked transaction has
* finished, either by abort or commit completion.
*/
void
xfs_trans_del_item(
struct xfs_log_item *lip)
{
clear_bit(XFS_LI_DIRTY, &lip->li_flags);
list_del_init(&lip->li_trans);
}
/* Detach and unlock all of the items in a transaction */
static void
xfs_trans_free_items(
struct xfs_trans *tp,
bool abort)
{
struct xfs_log_item *lip, *next;
trace_xfs_trans_free_items(tp, _RET_IP_);
list_for_each_entry_safe(lip, next, &tp->t_items, li_trans) {
xfs_trans_del_item(lip);
if (abort)
set_bit(XFS_LI_ABORTED, &lip->li_flags);
if (lip->li_ops->iop_release)
lip->li_ops->iop_release(lip);
}
}
static inline void
xfs_log_item_batch_insert(
struct xfs_ail *ailp,
struct xfs_ail_cursor *cur,
struct xfs_log_item **log_items,
int nr_items,
xfs_lsn_t commit_lsn)
{
int i;
spin_lock(&ailp->ail_lock);
/* xfs_trans_ail_update_bulk drops ailp->ail_lock */
xfs_trans_ail_update_bulk(ailp, cur, log_items, nr_items, commit_lsn);
for (i = 0; i < nr_items; i++) {
struct xfs_log_item *lip = log_items[i];
if (lip->li_ops->iop_unpin)
lip->li_ops->iop_unpin(lip, 0);
}
}
/*
* Bulk operation version of xfs_trans_committed that takes a log vector of
* items to insert into the AIL. This uses bulk AIL insertion techniques to
* minimise lock traffic.
*
* If we are called with the aborted flag set, it is because a log write during
* a CIL checkpoint commit has failed. In this case, all the items in the
* checkpoint have already gone through iop_committed and iop_committing, which
* means that checkpoint commit abort handling is treated exactly the same
* as an iclog write error even though we haven't started any IO yet. Hence in
* this case all we need to do is iop_committed processing, followed by an
* iop_unpin(aborted) call.
*
* The AIL cursor is used to optimise the insert process. If commit_lsn is not
* at the end of the AIL, the insert cursor avoids the need to walk
* the AIL to find the insertion point on every xfs_log_item_batch_insert()
* call. This saves a lot of needless list walking and is a net win, even
* though it slightly increases that amount of AIL lock traffic to set it up
* and tear it down.
*/
void
xfs_trans_committed_bulk(
struct xfs_ail *ailp,
struct xfs_log_vec *log_vector,
xfs_lsn_t commit_lsn,
bool aborted)
{
#define LOG_ITEM_BATCH_SIZE 32
struct xfs_log_item *log_items[LOG_ITEM_BATCH_SIZE];
struct xfs_log_vec *lv;
struct xfs_ail_cursor cur;
int i = 0;
spin_lock(&ailp->ail_lock);
xfs_trans_ail_cursor_last(ailp, &cur, commit_lsn);
spin_unlock(&ailp->ail_lock);
/* unpin all the log items */
for (lv = log_vector; lv; lv = lv->lv_next ) {
struct xfs_log_item *lip = lv->lv_item;
xfs_lsn_t item_lsn;
if (aborted)
set_bit(XFS_LI_ABORTED, &lip->li_flags);
if (lip->li_ops->flags & XFS_ITEM_RELEASE_WHEN_COMMITTED) {
lip->li_ops->iop_release(lip);
continue;
}
if (lip->li_ops->iop_committed)
item_lsn = lip->li_ops->iop_committed(lip, commit_lsn);
else
item_lsn = commit_lsn;
/* item_lsn of -1 means the item needs no further processing */
if (XFS_LSN_CMP(item_lsn, (xfs_lsn_t)-1) == 0)
continue;
/*
* if we are aborting the operation, no point in inserting the
* object into the AIL as we are in a shutdown situation.
*/
if (aborted) {
ASSERT(xfs_is_shutdown(ailp->ail_mount));
if (lip->li_ops->iop_unpin)
lip->li_ops->iop_unpin(lip, 1);
continue;
}
if (item_lsn != commit_lsn) {
/*
* Not a bulk update option due to unusual item_lsn.
* Push into AIL immediately, rechecking the lsn once
* we have the ail lock. Then unpin the item. This does
* not affect the AIL cursor the bulk insert path is
* using.
*/
spin_lock(&ailp->ail_lock);
if (XFS_LSN_CMP(item_lsn, lip->li_lsn) > 0)
xfs_trans_ail_update(ailp, lip, item_lsn);
else
spin_unlock(&ailp->ail_lock);
if (lip->li_ops->iop_unpin)
lip->li_ops->iop_unpin(lip, 0);
continue;
}
/* Item is a candidate for bulk AIL insert. */
log_items[i++] = lv->lv_item;
if (i >= LOG_ITEM_BATCH_SIZE) {
xfs_log_item_batch_insert(ailp, &cur, log_items,
LOG_ITEM_BATCH_SIZE, commit_lsn);
i = 0;
}
}
/* make sure we insert the remainder! */
if (i)
xfs_log_item_batch_insert(ailp, &cur, log_items, i, commit_lsn);
spin_lock(&ailp->ail_lock);
xfs_trans_ail_cursor_done(&cur);
spin_unlock(&ailp->ail_lock);
}
/*
* Commit the given transaction to the log.
*
* XFS disk error handling mechanism is not based on a typical
* transaction abort mechanism. Logically after the filesystem
* gets marked 'SHUTDOWN', we can't let any new transactions
* be durable - ie. committed to disk - because some metadata might
* be inconsistent. In such cases, this returns an error, and the
* caller may assume that all locked objects joined to the transaction
* have already been unlocked as if the commit had succeeded.
* Do not reference the transaction structure after this call.
*/
static int
__xfs_trans_commit(
struct xfs_trans *tp,
bool regrant)
{
struct xfs_mount *mp = tp->t_mountp;
xfs_csn_t commit_seq = 0;
int error = 0;
int sync = tp->t_flags & XFS_TRANS_SYNC;
trace_xfs_trans_commit(tp, _RET_IP_);
/*
* Finish deferred items on final commit. Only permanent transactions
* should ever have deferred ops.
*/
WARN_ON_ONCE(!list_empty(&tp->t_dfops) &&
!(tp->t_flags & XFS_TRANS_PERM_LOG_RES));
if (!regrant && (tp->t_flags & XFS_TRANS_PERM_LOG_RES)) {
error = xfs_defer_finish_noroll(&tp);
if (error)
goto out_unreserve;
}
/*
* If there is nothing to be logged by the transaction,
* then unlock all of the items associated with the
* transaction and free the transaction structure.
* Also make sure to return any reserved blocks to
* the free pool.
*/
if (!(tp->t_flags & XFS_TRANS_DIRTY))
goto out_unreserve;
if (xfs_is_shutdown(mp)) {
error = -EIO;
goto out_unreserve;
}
ASSERT(tp->t_ticket != NULL);
/*
* If we need to update the superblock, then do it now.
*/
if (tp->t_flags & XFS_TRANS_SB_DIRTY)
xfs_trans_apply_sb_deltas(tp);
xfs_trans_apply_dquot_deltas(tp);
xlog_cil_commit(mp->m_log, tp, &commit_seq, regrant);
xfs_trans_free(tp);
/*
* If the transaction needs to be synchronous, then force the
* log out now and wait for it.
*/
if (sync) {
error = xfs_log_force_seq(mp, commit_seq, XFS_LOG_SYNC, NULL);
XFS_STATS_INC(mp, xs_trans_sync);
} else {
XFS_STATS_INC(mp, xs_trans_async);
}
return error;
out_unreserve:
xfs_trans_unreserve_and_mod_sb(tp);
/*
* It is indeed possible for the transaction to be not dirty but
* the dqinfo portion to be. All that means is that we have some
* (non-persistent) quota reservations that need to be unreserved.
*/
xfs_trans_unreserve_and_mod_dquots(tp);
if (tp->t_ticket) {
if (regrant && !xlog_is_shutdown(mp->m_log))
xfs_log_ticket_regrant(mp->m_log, tp->t_ticket);
else
xfs_log_ticket_ungrant(mp->m_log, tp->t_ticket);
tp->t_ticket = NULL;
}
xfs_trans_free_items(tp, !!error);
xfs_trans_free(tp);
XFS_STATS_INC(mp, xs_trans_empty);
return error;
}
int
xfs_trans_commit(
struct xfs_trans *tp)
{
return __xfs_trans_commit(tp, false);
}
/*
* Unlock all of the transaction's items and free the transaction.
* The transaction must not have modified any of its items, because
* there is no way to restore them to their previous state.
*
* If the transaction has made a log reservation, make sure to release
* it as well.
*/
void
xfs_trans_cancel(
struct xfs_trans *tp)
{
struct xfs_mount *mp = tp->t_mountp;
bool dirty = (tp->t_flags & XFS_TRANS_DIRTY);
trace_xfs_trans_cancel(tp, _RET_IP_);
/*
* It's never valid to cancel a transaction with deferred ops attached,
* because the transaction is effectively dirty. Complain about this
* loudly before freeing the in-memory defer items.
*/
if (!list_empty(&tp->t_dfops)) {
ASSERT(xfs_is_shutdown(mp) || list_empty(&tp->t_dfops));
ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
dirty = true;
xfs_defer_cancel(tp);
}
/*
* See if the caller is relying on us to shut down the
* filesystem. This happens in paths where we detect
* corruption and decide to give up.
*/
if (dirty && !xfs_is_shutdown(mp)) {
XFS_ERROR_REPORT("xfs_trans_cancel", XFS_ERRLEVEL_LOW, mp);
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
}
#ifdef DEBUG
if (!dirty && !xfs_is_shutdown(mp)) {
struct xfs_log_item *lip;
list_for_each_entry(lip, &tp->t_items, li_trans)
ASSERT(!xlog_item_is_intent_done(lip));
}
#endif
xfs_trans_unreserve_and_mod_sb(tp);
xfs_trans_unreserve_and_mod_dquots(tp);
if (tp->t_ticket) {
xfs_log_ticket_ungrant(mp->m_log, tp->t_ticket);
tp->t_ticket = NULL;
}
xfs_trans_free_items(tp, dirty);
xfs_trans_free(tp);
}
/*
* Roll from one trans in the sequence of PERMANENT transactions to
* the next: permanent transactions are only flushed out when
* committed with xfs_trans_commit(), but we still want as soon
* as possible to let chunks of it go to the log. So we commit the
* chunk we've been working on and get a new transaction to continue.
*/
int
xfs_trans_roll(
struct xfs_trans **tpp)
{
struct xfs_trans *trans = *tpp;
struct xfs_trans_res tres;
int error;
trace_xfs_trans_roll(trans, _RET_IP_);
/*
* Copy the critical parameters from one trans to the next.
*/
tres.tr_logres = trans->t_log_res;
tres.tr_logcount = trans->t_log_count;
*tpp = xfs_trans_dup(trans);
/*
* Commit the current transaction.
* If this commit failed, then it'd just unlock those items that
* are not marked ihold. That also means that a filesystem shutdown
* is in progress. The caller takes the responsibility to cancel
* the duplicate transaction that gets returned.
*/
error = __xfs_trans_commit(trans, true);
if (error)
return error;
/*
* Reserve space in the log for the next transaction.
* This also pushes items in the "AIL", the list of logged items,
* out to disk if they are taking up space at the tail of the log
* that we want to use. This requires that either nothing be locked
* across this call, or that anything that is locked be logged in
* the prior and the next transactions.
*/
tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
return xfs_trans_reserve(*tpp, &tres, 0, 0);
}
/*
* Allocate an transaction, lock and join the inode to it, and reserve quota.
*
* The caller must ensure that the on-disk dquots attached to this inode have
* already been allocated and initialized. The caller is responsible for
* releasing ILOCK_EXCL if a new transaction is returned.
*/
int
xfs_trans_alloc_inode(
struct xfs_inode *ip,
struct xfs_trans_res *resv,
unsigned int dblocks,
unsigned int rblocks,
bool force,
struct xfs_trans **tpp)
{
struct xfs_trans *tp;
struct xfs_mount *mp = ip->i_mount;
bool retried = false;
int error;
retry:
error = xfs_trans_alloc(mp, resv, dblocks,
rblocks / mp->m_sb.sb_rextsize,
force ? XFS_TRANS_RESERVE : 0, &tp);
if (error)
return error;
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, 0);
error = xfs_qm_dqattach_locked(ip, false);
if (error) {
/* Caller should have allocated the dquots! */
ASSERT(error != -ENOENT);
goto out_cancel;
}
error = xfs_trans_reserve_quota_nblks(tp, ip, dblocks, rblocks, force);
if ((error == -EDQUOT || error == -ENOSPC) && !retried) {
xfs_trans_cancel(tp);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
xfs_blockgc_free_quota(ip, 0);
retried = true;
goto retry;
}
if (error)
goto out_cancel;
*tpp = tp;
return 0;
out_cancel:
xfs_trans_cancel(tp);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
return error;
}
/*
* Allocate an transaction in preparation for inode creation by reserving quota
* against the given dquots. Callers are not required to hold any inode locks.
*/
int
xfs_trans_alloc_icreate(
struct xfs_mount *mp,
struct xfs_trans_res *resv,
struct xfs_dquot *udqp,
struct xfs_dquot *gdqp,
struct xfs_dquot *pdqp,
unsigned int dblocks,
struct xfs_trans **tpp)
{
struct xfs_trans *tp;
bool retried = false;
int error;
retry:
error = xfs_trans_alloc(mp, resv, dblocks, 0, 0, &tp);
if (error)
return error;
error = xfs_trans_reserve_quota_icreate(tp, udqp, gdqp, pdqp, dblocks);
if ((error == -EDQUOT || error == -ENOSPC) && !retried) {
xfs_trans_cancel(tp);
xfs_blockgc_free_dquots(mp, udqp, gdqp, pdqp, 0);
retried = true;
goto retry;
}
if (error) {
xfs_trans_cancel(tp);
return error;
}
*tpp = tp;
return 0;
}
/*
* Allocate an transaction, lock and join the inode to it, and reserve quota
* in preparation for inode attribute changes that include uid, gid, or prid
* changes.
*
* The caller must ensure that the on-disk dquots attached to this inode have
* already been allocated and initialized. The ILOCK will be dropped when the
* transaction is committed or cancelled.
*/
int
xfs_trans_alloc_ichange(
struct xfs_inode *ip,
struct xfs_dquot *new_udqp,
struct xfs_dquot *new_gdqp,
struct xfs_dquot *new_pdqp,
bool force,
struct xfs_trans **tpp)
{
struct xfs_trans *tp;
struct xfs_mount *mp = ip->i_mount;
struct xfs_dquot *udqp;
struct xfs_dquot *gdqp;
struct xfs_dquot *pdqp;
bool retried = false;
int error;
retry:
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ichange, 0, 0, 0, &tp);
if (error)
return error;
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
error = xfs_qm_dqattach_locked(ip, false);
if (error) {
/* Caller should have allocated the dquots! */
ASSERT(error != -ENOENT);
goto out_cancel;
}
/*
* For each quota type, skip quota reservations if the inode's dquots
* now match the ones that came from the caller, or the caller didn't
* pass one in. The inode's dquots can change if we drop the ILOCK to
* perform a blockgc scan, so we must preserve the caller's arguments.
*/
udqp = (new_udqp != ip->i_udquot) ? new_udqp : NULL;
gdqp = (new_gdqp != ip->i_gdquot) ? new_gdqp : NULL;
pdqp = (new_pdqp != ip->i_pdquot) ? new_pdqp : NULL;
if (udqp || gdqp || pdqp) {
unsigned int qflags = XFS_QMOPT_RES_REGBLKS;
if (force)
qflags |= XFS_QMOPT_FORCE_RES;
/*
* Reserve enough quota to handle blocks on disk and reserved
* for a delayed allocation. We'll actually transfer the
* delalloc reservation between dquots at chown time, even
* though that part is only semi-transactional.
*/
error = xfs_trans_reserve_quota_bydquots(tp, mp, udqp, gdqp,
pdqp, ip->i_nblocks + ip->i_delayed_blks,
1, qflags);
if ((error == -EDQUOT || error == -ENOSPC) && !retried) {
xfs_trans_cancel(tp);
xfs_blockgc_free_dquots(mp, udqp, gdqp, pdqp, 0);
retried = true;
goto retry;
}
if (error)
goto out_cancel;
}
*tpp = tp;
return 0;
out_cancel:
xfs_trans_cancel(tp);
return error;
}