// 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"
#include "xfs_rtbitmap.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 *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);
}
#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_highest_agno = NULLAGNUMBER;
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_dec_fdblocks(mp, 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, 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_dec_frextents(mp, 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_add_fdblocks(mp, blocks);
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_highest_agno = NULLAGNUMBER;
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.
*/
error = xfs_blockgc_flush_all(mp);
if (error)
return error;
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);
}
/*
* Updating frextents requires careful handling because it does not
* behave like the lazysb counters because we cannot rely on log
* recovery in older kenels to recompute the value from the rtbitmap.
* This means that the ondisk frextents must be consistent with the
* rtbitmap.
*
* Therefore, log the frextents change to the ondisk superblock and
* update the incore superblock so that future calls to xfs_log_sb
* write the correct value ondisk.
*
* Don't touch m_frextents because it includes incore reservations,
* and those are handled by the unreserve function.
*/
if (tp->t_frextents_delta || tp->t_res_frextents_delta) {
struct xfs_mount *mp = tp->t_mountp;
int64_t rtxdelta;
rtxdelta = tp->t_frextents_delta + tp->t_res_frextents_delta;
spin_lock(&mp->m_sb_lock);
be64_add_cpu(&sbp->sb_frextents, rtxdelta);
mp->m_sb.sb_frextents += rtxdelta;
spin_unlock(&mp->m_sb_lock);
}
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;
int64_t blkdelta = tp->t_blk_res;
int64_t rtxdelta = tp->t_rtx_res;
int64_t idelta = 0;
int64_t ifreedelta = 0;
/*
* Calculate the deltas.
*
* t_fdblocks_delta and t_frextents_delta can be positive or negative:
*
* - positive values indicate blocks freed in the transaction.
* - negative values indicate blocks allocated in the transaction
*
* Negative values can only happen if the transaction has a block
* reservation that covers the allocated block. The end result is
* that the calculated delta values must always be positive and we
* can only put back previous allocated or reserved blocks here.
*/
ASSERT(tp->t_blk_res || tp->t_fdblocks_delta >= 0);
if (xfs_has_lazysbcount(mp) || (tp->t_flags & XFS_TRANS_SB_DIRTY)) {
blkdelta += tp->t_fdblocks_delta;
ASSERT(blkdelta >= 0);
}
ASSERT(tp->t_rtx_res || tp->t_frextents_delta >= 0);
if (tp->t_flags & XFS_TRANS_SB_DIRTY) {
rtxdelta += tp->t_frextents_delta;
ASSERT(rtxdelta >= 0);
}
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)
xfs_add_fdblocks(mp, blkdelta);
if (idelta)
percpu_counter_add_batch(&mp->m_icount, idelta,
XFS_ICOUNT_BATCH);
if (ifreedelta)
percpu_counter_add(&mp->m_ifree, ifreedelta);
if (rtxdelta)
xfs_add_frextents(mp, rtxdelta);
if (!(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;
/*
* Do not touch sb_frextents here because we are dealing with incore
* reservation. sb_frextents is not part of the lazy sb counters so it
* must be consistent with the ondisk rtbitmap and must never include
* incore reservations.
*/
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;
if (tp->t_rextsize_delta) {
mp->m_rtxblklog = log2_if_power2(mp->m_sb.sb_rextsize);
mp->m_rtxblkmask = mask64_if_power2(mp->m_sb.sb_rextsize);
}
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);
}
/* 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_log == tp->t_mountp->m_log);
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);
}
}
/*
* Sort transaction items prior to running precommit operations. This will
* attempt to order the items such that they will always be locked in the same
* order. Items that have no sort function are moved to the end of the list
* and so are locked last.
*
* This may need refinement as different types of objects add sort functions.
*
* Function is more complex than it needs to be because we are comparing 64 bit
* values and the function only returns 32 bit values.
*/
static int
xfs_trans_precommit_sort(
void *unused_arg,
const struct list_head *a,
const struct list_head *b)
{
struct xfs_log_item *lia = container_of(a,
struct xfs_log_item, li_trans);
struct xfs_log_item *lib = container_of(b,
struct xfs_log_item, li_trans);
int64_t diff;
/*
* If both items are non-sortable, leave them alone. If only one is
* sortable, move the non-sortable item towards the end of the list.
*/
if (!lia->li_ops->iop_sort && !lib->li_ops->iop_sort)
return 0;
if (!lia->li_ops->iop_sort)
return 1;
if (!lib->li_ops->iop_sort)
return -1;
diff = lia->li_ops->iop_sort(lia) - lib->li_ops->iop_sort(lib);
if (diff < 0)
return -1;
if (diff > 0)
return 1;
return 0;
}
/*
* Run transaction precommit functions.
*
* If there is an error in any of the callouts, then stop immediately and
* trigger a shutdown to abort the transaction. There is no recovery possible
* from errors at this point as the transaction is dirty....
*/
static int
xfs_trans_run_precommits(
struct xfs_trans *tp)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_log_item *lip, *n;
int error = 0;
/*
* Sort the item list to avoid ABBA deadlocks with other transactions
* running precommit operations that lock multiple shared items such as
* inode cluster buffers.
*/
list_sort(NULL, &tp->t_items, xfs_trans_precommit_sort);
/*
* Precommit operations can remove the log item from the transaction
* if the log item exists purely to delay modifications until they
* can be ordered against other operations. Hence we have to use
* list_for_each_entry_safe() here.
*/
list_for_each_entry_safe(lip, n, &tp->t_items, li_trans) {
if (!test_bit(XFS_LI_DIRTY, &lip->li_flags))
continue;
if (lip->li_ops->iop_precommit) {
error = lip->li_ops->iop_precommit(tp, lip);
if (error)
break;
}
}
if (error)
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
return error;
}
/*
* 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;
struct xlog *log = mp->m_log;
xfs_csn_t commit_seq = 0;
int error = 0;
int sync = tp->t_flags & XFS_TRANS_SYNC;
trace_xfs_trans_commit(tp, _RET_IP_);
error = xfs_trans_run_precommits(tp);
if (error) {
if (tp->t_flags & XFS_TRANS_PERM_LOG_RES)
xfs_defer_cancel(tp);
goto out_unreserve;
}
/*
* 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;
/* Run precommits from final tx in defer chain. */
error = xfs_trans_run_precommits(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;
/*
* We must check against log shutdown here because we cannot abort log
* items and leave them dirty, inconsistent and unpinned in memory while
* the log is active. This leaves them open to being written back to
* disk, and that will lead to on-disk corruption.
*/
if (xlog_is_shutdown(log)) {
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(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(log))
xfs_log_ticket_regrant(log, tp->t_ticket);
else
xfs_log_ticket_ungrant(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. If the
* transaction is dirty, we must shut down the filesystem 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.
*
* This is a high level function (equivalent to xfs_trans_commit()) and so can
* be called after the transaction has effectively been aborted due to the mount
* being shut down. However, if the mount has not been shut down and the
* transaction is dirty we will shut the mount down and, in doing so, that
* guarantees that the log is shut down, too. Hence we don't need to be as
* careful with shutdown state and dirty items here as we need to be in
* xfs_trans_commit().
*/
void
xfs_trans_cancel(
struct xfs_trans *tp)
{
struct xfs_mount *mp = tp->t_mountp;
struct xlog *log = mp->m_log;
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 and shutting down the
* filesystem.
*/
if (!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. We
* only want an error report if there isn't already a shutdown in
* progress, so we only need to check against the mount shutdown state
* here.
*/
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
/* Log items need to be consistent until the log is shut down. */
if (!dirty && !xlog_is_shutdown(log)) {
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(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,
xfs_extlen_to_rtxlen(mp, rblocks),
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;
}
/*
* Try to reserve more blocks for a transaction.
*
* This is for callers that need to attach resources to a transaction, scan
* those resources to determine the space reservation requirements, and then
* modify the attached resources. In other words, online repair. This can
* fail due to ENOSPC, so the caller must be able to cancel the transaction
* without shutting down the fs.
*/
int
xfs_trans_reserve_more(
struct xfs_trans *tp,
unsigned int blocks,
unsigned int rtextents)
{
struct xfs_trans_res resv = { };
return xfs_trans_reserve(tp, &resv, blocks, rtextents);
}
/*
* Try to reserve more blocks and file quota for a transaction. Same
* conditions of usage as xfs_trans_reserve_more.
*/
int
xfs_trans_reserve_more_inode(
struct xfs_trans *tp,
struct xfs_inode *ip,
unsigned int dblocks,
unsigned int rblocks,
bool force_quota)
{
struct xfs_trans_res resv = { };
struct xfs_mount *mp = ip->i_mount;
unsigned int rtx = xfs_extlen_to_rtxlen(mp, rblocks);
int error;
xfs_assert_ilocked(ip, XFS_ILOCK_EXCL);
error = xfs_trans_reserve(tp, &resv, dblocks, rtx);
if (error)
return error;
if (!XFS_IS_QUOTA_ON(mp) || xfs_is_quota_inode(&mp->m_sb, ip->i_ino))
return 0;
if (tp->t_flags & XFS_TRANS_RESERVE)
force_quota = true;
error = xfs_trans_reserve_quota_nblks(tp, ip, dblocks, rblocks,
force_quota);
if (!error)
return 0;
/* Quota failed, give back the new reservation. */
xfs_add_fdblocks(mp, dblocks);
tp->t_blk_res -= dblocks;
xfs_add_frextents(mp, rtx);
tp->t_rtx_res -= rtx;
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;
}
/*
* Allocate an transaction, lock and join the directory and child inodes to it,
* and reserve quota for a directory update. If there isn't sufficient space,
* @dblocks will be set to zero for a reservationless directory update and
* @nospace_error will be set to a negative errno describing the space
* constraint we hit.
*
* The caller must ensure that the on-disk dquots attached to this inode have
* already been allocated and initialized. The ILOCKs will be dropped when the
* transaction is committed or cancelled.
*
* Caller is responsible for unlocking the inodes manually upon return
*/
int
xfs_trans_alloc_dir(
struct xfs_inode *dp,
struct xfs_trans_res *resv,
struct xfs_inode *ip,
unsigned int *dblocks,
struct xfs_trans **tpp,
int *nospace_error)
{
struct xfs_trans *tp;
struct xfs_mount *mp = ip->i_mount;
unsigned int resblks;
bool retried = false;
int error;
retry:
*nospace_error = 0;
resblks = *dblocks;
error = xfs_trans_alloc(mp, resv, resblks, 0, 0, &tp);
if (error == -ENOSPC) {
*nospace_error = error;
resblks = 0;
error = xfs_trans_alloc(mp, resv, resblks, 0, 0, &tp);
}
if (error)
return error;
xfs_lock_two_inodes(dp, XFS_ILOCK_EXCL, ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, dp, 0);
xfs_trans_ijoin(tp, ip, 0);
error = xfs_qm_dqattach_locked(dp, false);
if (error) {
/* Caller should have allocated the dquots! */
ASSERT(error != -ENOENT);
goto out_cancel;
}
error = xfs_qm_dqattach_locked(ip, false);
if (error) {
/* Caller should have allocated the dquots! */
ASSERT(error != -ENOENT);
goto out_cancel;
}
if (resblks == 0)
goto done;
error = xfs_trans_reserve_quota_nblks(tp, dp, resblks, 0, false);
if (error == -EDQUOT || error == -ENOSPC) {
if (!retried) {
xfs_trans_cancel(tp);
xfs_iunlock(dp, XFS_ILOCK_EXCL);
if (dp != ip)
xfs_iunlock(ip, XFS_ILOCK_EXCL);
xfs_blockgc_free_quota(dp, 0);
retried = true;
goto retry;
}
*nospace_error = error;
resblks = 0;
error = 0;
}
if (error)
goto out_cancel;
done:
*tpp = tp;
*dblocks = resblks;
return 0;
out_cancel:
xfs_trans_cancel(tp);
return error;
}
Codebase Browser
linux