acrn-kernel/fs/xfs/xfs_trans.c

1027 lines
28 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_log_priv.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_trace.h"
#include "xfs_error.h"
#include "xfs_defer.h"
kmem_zone_t *xfs_trans_zone;
#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_);
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_zone, 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_zone, 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;
ntp->t_pflags = tp->t_pflags;
/* 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;
/* Mark this thread as being in a transaction */
current_set_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
/*
* 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) {
current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
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;
}
current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
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;
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().
*/
tp = kmem_cache_zalloc(xfs_trans_zone, GFP_KERNEL | __GFP_NOFAIL);
if (!(flags & XFS_TRANS_NO_WRITECOUNT))
sb_start_intwrite(mp->m_super);
/*
* 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_sb_version_haslazysbcount(&mp->m_sb));
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) {
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_sb_version_haslazysbcount(&mp->m_sb))
flags &= ~XFS_TRANS_SB_DIRTY;
break;
case XFS_TRANS_SB_IFREE:
tp->t_ifree_delta += delta;
if (xfs_sb_version_haslazysbcount(&mp->m_sb))
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_sb_version_haslazysbcount(&mp->m_sb))
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_sb_version_haslazysbcount(&mp->m_sb))
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:
ASSERT(delta > 0);
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)
{
xfs_dsb_t *sbp;
xfs_buf_t *bp;
int whole = 0;
bp = xfs_trans_getsb(tp, tp->t_mountp);
sbp = bp->b_addr;
/*
* Check that superblock mods match the mods made to AGF counters.
*/
ASSERT((tp->t_fdblocks_delta + tp->t_res_fdblocks_delta) ==
(tp->t_ag_freeblks_delta + tp->t_ag_flist_delta +
tp->t_ag_btree_delta));
/*
* Only update the superblock counters if we are logging them
*/
if (!xfs_sb_version_haslazysbcount(&(tp->t_mountp->m_sb))) {
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(xfs_dsb_t) - 1);
else
/*
* Since all the modifiable fields are contiguous, we
* can get away with this.
*/
xfs_trans_log_buf(tp, bp, offsetof(xfs_dsb_t, sb_icount),
offsetof(xfs_dsb_t, 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_sb_version_haslazysbcount(&mp->m_sb) ||
(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_sb_version_haslazysbcount(&mp->m_sb) ||
(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 (idelta < 0)
ASSERT(__percpu_counter_compare(&mp->m_icount, 0,
XFS_ICOUNT_BATCH) >= 0);
}
if (ifreedelta) {
percpu_counter_add(&mp->m_ifree, ifreedelta);
if (ifreedelta < 0)
ASSERT(percpu_counter_compare(&mp->m_ifree, 0) >= 0);
}
if (rtxdelta == 0 && !(tp->t_flags & XFS_TRANS_SB_DIRTY))
return;
/* apply remaining deltas */
spin_lock(&mp->m_sb_lock);
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_FORCED_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_lsn_t commit_lsn = -1;
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_FORCED_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);
xfs_log_commit_cil(mp, tp, &commit_lsn, regrant);
current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
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_lsn(mp, commit_lsn, 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_FORCED_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;
}
current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
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_);
if (tp->t_flags & XFS_TRANS_PERM_LOG_RES)
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_FORCED_SHUTDOWN(mp)) {
XFS_ERROR_REPORT("xfs_trans_cancel", XFS_ERRLEVEL_LOW, mp);
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
}
#ifdef DEBUG
if (!dirty && !XFS_FORCED_SHUTDOWN(mp)) {
struct xfs_log_item *lip;
list_for_each_entry(lip, &tp->t_items, li_trans)
ASSERT(!(lip->li_type == XFS_LI_EFD));
}
#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;
}
/* mark this thread as no longer being in a transaction */
current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
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);
}