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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/xfs/xfs_trans.c
downloadop-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
op-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/xfs/xfs_trans.c')
-rw-r--r--fs/xfs/xfs_trans.c1315
1 files changed, 1315 insertions, 0 deletions
diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
new file mode 100644
index 0000000..3db0e22
--- /dev/null
+++ b/fs/xfs/xfs_trans.c
@@ -0,0 +1,1315 @@
+/*
+ * Copyright (c) 2000-2003 Silicon Graphics, Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like. Any license provided herein, whether implied or
+ * otherwise, applies only to this software file. Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA 94043, or:
+ *
+ * http://www.sgi.com
+ *
+ * For further information regarding this notice, see:
+ *
+ * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
+ */
+
+#include "xfs.h"
+#include "xfs_macros.h"
+#include "xfs_types.h"
+#include "xfs_inum.h"
+#include "xfs_log.h"
+#include "xfs_trans.h"
+#include "xfs_sb.h"
+#include "xfs_ag.h"
+#include "xfs_dir.h"
+#include "xfs_dir2.h"
+#include "xfs_dmapi.h"
+#include "xfs_mount.h"
+#include "xfs_error.h"
+#include "xfs_trans_priv.h"
+#include "xfs_alloc_btree.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_ialloc_btree.h"
+#include "xfs_btree.h"
+#include "xfs_ialloc.h"
+#include "xfs_alloc.h"
+#include "xfs_attr_sf.h"
+#include "xfs_dir_sf.h"
+#include "xfs_dir2_sf.h"
+#include "xfs_dinode.h"
+#include "xfs_inode.h"
+#include "xfs_bmap.h"
+#include "xfs_da_btree.h"
+#include "xfs_quota.h"
+#include "xfs_trans_space.h"
+
+
+STATIC void xfs_trans_apply_sb_deltas(xfs_trans_t *);
+STATIC uint xfs_trans_count_vecs(xfs_trans_t *);
+STATIC void xfs_trans_fill_vecs(xfs_trans_t *, xfs_log_iovec_t *);
+STATIC void xfs_trans_uncommit(xfs_trans_t *, uint);
+STATIC void xfs_trans_committed(xfs_trans_t *, int);
+STATIC void xfs_trans_chunk_committed(xfs_log_item_chunk_t *, xfs_lsn_t, int);
+STATIC void xfs_trans_free(xfs_trans_t *);
+
+kmem_zone_t *xfs_trans_zone;
+
+
+/*
+ * Initialize the precomputed transaction reservation values
+ * in the mount structure.
+ */
+void
+xfs_trans_init(
+ xfs_mount_t *mp)
+{
+ xfs_trans_reservations_t *resp;
+
+ resp = &(mp->m_reservations);
+ resp->tr_write =
+ (uint)(XFS_CALC_WRITE_LOG_RES(mp) + XFS_DQUOT_LOGRES(mp));
+ resp->tr_itruncate =
+ (uint)(XFS_CALC_ITRUNCATE_LOG_RES(mp) + XFS_DQUOT_LOGRES(mp));
+ resp->tr_rename =
+ (uint)(XFS_CALC_RENAME_LOG_RES(mp) + XFS_DQUOT_LOGRES(mp));
+ resp->tr_link = (uint)XFS_CALC_LINK_LOG_RES(mp);
+ resp->tr_remove =
+ (uint)(XFS_CALC_REMOVE_LOG_RES(mp) + XFS_DQUOT_LOGRES(mp));
+ resp->tr_symlink =
+ (uint)(XFS_CALC_SYMLINK_LOG_RES(mp) + XFS_DQUOT_LOGRES(mp));
+ resp->tr_create =
+ (uint)(XFS_CALC_CREATE_LOG_RES(mp) + XFS_DQUOT_LOGRES(mp));
+ resp->tr_mkdir =
+ (uint)(XFS_CALC_MKDIR_LOG_RES(mp) + XFS_DQUOT_LOGRES(mp));
+ resp->tr_ifree =
+ (uint)(XFS_CALC_IFREE_LOG_RES(mp) + XFS_DQUOT_LOGRES(mp));
+ resp->tr_ichange =
+ (uint)(XFS_CALC_ICHANGE_LOG_RES(mp) + XFS_DQUOT_LOGRES(mp));
+ resp->tr_growdata = (uint)XFS_CALC_GROWDATA_LOG_RES(mp);
+ resp->tr_swrite = (uint)XFS_CALC_SWRITE_LOG_RES(mp);
+ resp->tr_writeid = (uint)XFS_CALC_WRITEID_LOG_RES(mp);
+ resp->tr_addafork =
+ (uint)(XFS_CALC_ADDAFORK_LOG_RES(mp) + XFS_DQUOT_LOGRES(mp));
+ resp->tr_attrinval = (uint)XFS_CALC_ATTRINVAL_LOG_RES(mp);
+ resp->tr_attrset =
+ (uint)(XFS_CALC_ATTRSET_LOG_RES(mp) + XFS_DQUOT_LOGRES(mp));
+ resp->tr_attrrm =
+ (uint)(XFS_CALC_ATTRRM_LOG_RES(mp) + XFS_DQUOT_LOGRES(mp));
+ resp->tr_clearagi = (uint)XFS_CALC_CLEAR_AGI_BUCKET_LOG_RES(mp);
+ resp->tr_growrtalloc = (uint)XFS_CALC_GROWRTALLOC_LOG_RES(mp);
+ resp->tr_growrtzero = (uint)XFS_CALC_GROWRTZERO_LOG_RES(mp);
+ resp->tr_growrtfree = (uint)XFS_CALC_GROWRTFREE_LOG_RES(mp);
+}
+
+/*
+ * This routine is called to allocate a transaction structure.
+ * The type parameter indicates the type of the transaction. These
+ * are enumerated in xfs_trans.h.
+ *
+ * Dynamically allocate the transaction structure from the transaction
+ * zone, initialize it, and return it to the caller.
+ */
+xfs_trans_t *
+xfs_trans_alloc(
+ xfs_mount_t *mp,
+ uint type)
+{
+ fs_check_frozen(XFS_MTOVFS(mp), SB_FREEZE_TRANS);
+ atomic_inc(&mp->m_active_trans);
+
+ return (_xfs_trans_alloc(mp, type));
+
+}
+
+xfs_trans_t *
+_xfs_trans_alloc(
+ xfs_mount_t *mp,
+ uint type)
+{
+ xfs_trans_t *tp;
+
+ ASSERT(xfs_trans_zone != NULL);
+ tp = kmem_zone_zalloc(xfs_trans_zone, KM_SLEEP);
+
+ /*
+ * Initialize the transaction structure.
+ */
+ tp->t_magic = XFS_TRANS_MAGIC;
+ tp->t_type = type;
+ tp->t_mountp = mp;
+ tp->t_items_free = XFS_LIC_NUM_SLOTS;
+ tp->t_busy_free = XFS_LBC_NUM_SLOTS;
+ XFS_LIC_INIT(&(tp->t_items));
+ XFS_LBC_INIT(&(tp->t_busy));
+
+ return (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.
+ */
+xfs_trans_t *
+xfs_trans_dup(
+ xfs_trans_t *tp)
+{
+ xfs_trans_t *ntp;
+
+ ntp = kmem_zone_zalloc(xfs_trans_zone, KM_SLEEP);
+
+ /*
+ * Initialize the new transaction structure.
+ */
+ ntp->t_magic = XFS_TRANS_MAGIC;
+ ntp->t_type = tp->t_type;
+ ntp->t_mountp = tp->t_mountp;
+ ntp->t_items_free = XFS_LIC_NUM_SLOTS;
+ ntp->t_busy_free = XFS_LBC_NUM_SLOTS;
+ XFS_LIC_INIT(&(ntp->t_items));
+ XFS_LBC_INIT(&(ntp->t_busy));
+
+ ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
+
+#if defined(XLOG_NOLOG) || defined(DEBUG)
+ ASSERT(!xlog_debug || tp->t_ticket != NULL);
+#else
+ ASSERT(tp->t_ticket != NULL);
+#endif
+ ntp->t_flags = XFS_TRANS_PERM_LOG_RES | (tp->t_flags & XFS_TRANS_RESERVE);
+ ntp->t_ticket = tp->t_ticket;
+ 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;
+ PFLAGS_DUP(&tp->t_pflags, &ntp->t_pflags);
+
+ XFS_TRANS_DUP_DQINFO(tp->t_mountp, tp, ntp);
+
+ atomic_inc(&tp->t_mountp->m_active_trans);
+ 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.
+ */
+int
+xfs_trans_reserve(
+ xfs_trans_t *tp,
+ uint blocks,
+ uint logspace,
+ uint rtextents,
+ uint flags,
+ uint logcount)
+{
+ int log_flags;
+ int error;
+ int rsvd;
+
+ error = 0;
+ rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
+
+ /* Mark this thread as being in a transaction */
+ PFLAGS_SET_FSTRANS(&tp->t_pflags);
+
+ /*
+ * 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_incore_sb(tp->t_mountp, XFS_SBS_FDBLOCKS,
+ -blocks, rsvd);
+ if (error != 0) {
+ PFLAGS_RESTORE_FSTRANS(&tp->t_pflags);
+ return (XFS_ERROR(ENOSPC));
+ }
+ tp->t_blk_res += blocks;
+ }
+
+ /*
+ * Reserve the log space needed for this transaction.
+ */
+ if (logspace > 0) {
+ ASSERT((tp->t_log_res == 0) || (tp->t_log_res == logspace));
+ ASSERT((tp->t_log_count == 0) ||
+ (tp->t_log_count == logcount));
+ if (flags & XFS_TRANS_PERM_LOG_RES) {
+ log_flags = XFS_LOG_PERM_RESERV;
+ tp->t_flags |= XFS_TRANS_PERM_LOG_RES;
+ } else {
+ ASSERT(tp->t_ticket == NULL);
+ ASSERT(!(tp->t_flags & XFS_TRANS_PERM_LOG_RES));
+ log_flags = 0;
+ }
+
+ error = xfs_log_reserve(tp->t_mountp, logspace, logcount,
+ &tp->t_ticket,
+ XFS_TRANSACTION, log_flags);
+ if (error) {
+ goto undo_blocks;
+ }
+ tp->t_log_res = logspace;
+ tp->t_log_count = 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_incore_sb(tp->t_mountp, XFS_SBS_FREXTENTS,
+ -rtextents, rsvd);
+ if (error) {
+ error = XFS_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 (logspace > 0) {
+ if (flags & XFS_TRANS_PERM_LOG_RES) {
+ log_flags = XFS_LOG_REL_PERM_RESERV;
+ } else {
+ log_flags = 0;
+ }
+ xfs_log_done(tp->t_mountp, tp->t_ticket, NULL, log_flags);
+ tp->t_ticket = NULL;
+ tp->t_log_res = 0;
+ tp->t_flags &= ~XFS_TRANS_PERM_LOG_RES;
+ }
+
+undo_blocks:
+ if (blocks > 0) {
+ (void) xfs_mod_incore_sb(tp->t_mountp, XFS_SBS_FDBLOCKS,
+ blocks, rsvd);
+ tp->t_blk_res = 0;
+ }
+
+ PFLAGS_RESTORE_FSTRANS(&tp->t_pflags);
+
+ return (error);
+}
+
+
+/*
+ * This is called to set the a callback to be called when the given
+ * transaction is committed to disk. The transaction pointer and the
+ * argument pointer will be passed to the callback routine.
+ *
+ * Only one callback can be associated with any single transaction.
+ */
+void
+xfs_trans_callback(
+ xfs_trans_t *tp,
+ xfs_trans_callback_t callback,
+ void *arg)
+{
+ ASSERT(tp->t_callback == NULL);
+ tp->t_callback = callback;
+ tp->t_callarg = arg;
+}
+
+
+/*
+ * 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.
+ */
+void
+xfs_trans_mod_sb(
+ xfs_trans_t *tp,
+ uint field,
+ long delta)
+{
+
+ switch (field) {
+ case XFS_TRANS_SB_ICOUNT:
+ tp->t_icount_delta += delta;
+ break;
+ case XFS_TRANS_SB_IFREE:
+ tp->t_ifree_delta += delta;
+ 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 (delta < 0) {
+ tp->t_blk_res_used += (uint)-delta;
+ ASSERT(tp->t_blk_res_used <= tp->t_blk_res);
+ }
+ tp->t_fdblocks_delta += delta;
+ 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.
+ */
+ ASSERT(delta < 0);
+ tp->t_res_fdblocks_delta += delta;
+ 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 superblocks'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 |= (XFS_TRANS_SB_DIRTY | XFS_TRANS_DIRTY);
+}
+
+/*
+ * 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_sb_t *sbp;
+ xfs_buf_t *bp;
+ int whole = 0;
+
+ bp = xfs_trans_getsb(tp, tp->t_mountp, 0);
+ sbp = XFS_BUF_TO_SBP(bp);
+
+ /*
+ * 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));
+
+ if (tp->t_icount_delta != 0) {
+ INT_MOD(sbp->sb_icount, ARCH_CONVERT, tp->t_icount_delta);
+ }
+ if (tp->t_ifree_delta != 0) {
+ INT_MOD(sbp->sb_ifree, ARCH_CONVERT, tp->t_ifree_delta);
+ }
+
+ if (tp->t_fdblocks_delta != 0) {
+ INT_MOD(sbp->sb_fdblocks, ARCH_CONVERT, tp->t_fdblocks_delta);
+ }
+ if (tp->t_res_fdblocks_delta != 0) {
+ INT_MOD(sbp->sb_fdblocks, ARCH_CONVERT, tp->t_res_fdblocks_delta);
+ }
+
+ if (tp->t_frextents_delta != 0) {
+ INT_MOD(sbp->sb_frextents, ARCH_CONVERT, tp->t_frextents_delta);
+ }
+ if (tp->t_res_frextents_delta != 0) {
+ INT_MOD(sbp->sb_frextents, ARCH_CONVERT, tp->t_res_frextents_delta);
+ }
+ if (tp->t_dblocks_delta != 0) {
+ INT_MOD(sbp->sb_dblocks, ARCH_CONVERT, tp->t_dblocks_delta);
+ whole = 1;
+ }
+ if (tp->t_agcount_delta != 0) {
+ INT_MOD(sbp->sb_agcount, ARCH_CONVERT, tp->t_agcount_delta);
+ whole = 1;
+ }
+ if (tp->t_imaxpct_delta != 0) {
+ INT_MOD(sbp->sb_imax_pct, ARCH_CONVERT, tp->t_imaxpct_delta);
+ whole = 1;
+ }
+ if (tp->t_rextsize_delta != 0) {
+ INT_MOD(sbp->sb_rextsize, ARCH_CONVERT, tp->t_rextsize_delta);
+ whole = 1;
+ }
+ if (tp->t_rbmblocks_delta != 0) {
+ INT_MOD(sbp->sb_rbmblocks, ARCH_CONVERT, tp->t_rbmblocks_delta);
+ whole = 1;
+ }
+ if (tp->t_rblocks_delta != 0) {
+ INT_MOD(sbp->sb_rblocks, ARCH_CONVERT, tp->t_rblocks_delta);
+ whole = 1;
+ }
+ if (tp->t_rextents_delta != 0) {
+ INT_MOD(sbp->sb_rextents, ARCH_CONVERT, tp->t_rextents_delta);
+ whole = 1;
+ }
+ if (tp->t_rextslog_delta != 0) {
+ INT_MOD(sbp->sb_rextslog, ARCH_CONVERT, tp->t_rextslog_delta);
+ whole = 1;
+ }
+
+ if (whole)
+ /*
+ * Log the whole thing, the fields are discontiguous.
+ */
+ xfs_trans_log_buf(tp, bp, 0, sizeof(xfs_sb_t) - 1);
+ else
+ /*
+ * Since all the modifiable fields are contiguous, we
+ * can get away with this.
+ */
+ xfs_trans_log_buf(tp, bp, offsetof(xfs_sb_t, sb_icount),
+ offsetof(xfs_sb_t, sb_frextents) +
+ sizeof(sbp->sb_frextents) - 1);
+
+ XFS_MTOVFS(tp->t_mountp)->vfs_super->s_dirt = 1;
+}
+
+/*
+ * xfs_trans_unreserve_and_mod_sb() is called to release unused
+ * reservations and apply superblock counter changes to the in-core
+ * superblock.
+ *
+ * This is done efficiently with a single call to xfs_mod_incore_sb_batch().
+ */
+void
+xfs_trans_unreserve_and_mod_sb(
+ xfs_trans_t *tp)
+{
+ xfs_mod_sb_t msb[14]; /* If you add cases, add entries */
+ xfs_mod_sb_t *msbp;
+ /* REFERENCED */
+ int error;
+ int rsvd;
+
+ msbp = msb;
+ rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
+
+ /*
+ * Release any reserved blocks. Any that were allocated
+ * will be taken back again by fdblocks_delta below.
+ */
+ if (tp->t_blk_res > 0) {
+ msbp->msb_field = XFS_SBS_FDBLOCKS;
+ msbp->msb_delta = tp->t_blk_res;
+ msbp++;
+ }
+
+ /*
+ * Release any reserved real time extents . Any that were
+ * allocated will be taken back again by frextents_delta below.
+ */
+ if (tp->t_rtx_res > 0) {
+ msbp->msb_field = XFS_SBS_FREXTENTS;
+ msbp->msb_delta = tp->t_rtx_res;
+ msbp++;
+ }
+
+ /*
+ * Apply any superblock modifications to the in-core version.
+ * The t_res_fdblocks_delta and t_res_frextents_delta fields are
+ * explicity NOT applied to the in-core superblock.
+ * The idea is that that has already been done.
+ */
+ if (tp->t_flags & XFS_TRANS_SB_DIRTY) {
+ if (tp->t_icount_delta != 0) {
+ msbp->msb_field = XFS_SBS_ICOUNT;
+ msbp->msb_delta = (int)tp->t_icount_delta;
+ msbp++;
+ }
+ if (tp->t_ifree_delta != 0) {
+ msbp->msb_field = XFS_SBS_IFREE;
+ msbp->msb_delta = (int)tp->t_ifree_delta;
+ msbp++;
+ }
+ if (tp->t_fdblocks_delta != 0) {
+ msbp->msb_field = XFS_SBS_FDBLOCKS;
+ msbp->msb_delta = (int)tp->t_fdblocks_delta;
+ msbp++;
+ }
+ if (tp->t_frextents_delta != 0) {
+ msbp->msb_field = XFS_SBS_FREXTENTS;
+ msbp->msb_delta = (int)tp->t_frextents_delta;
+ msbp++;
+ }
+ if (tp->t_dblocks_delta != 0) {
+ msbp->msb_field = XFS_SBS_DBLOCKS;
+ msbp->msb_delta = (int)tp->t_dblocks_delta;
+ msbp++;
+ }
+ if (tp->t_agcount_delta != 0) {
+ msbp->msb_field = XFS_SBS_AGCOUNT;
+ msbp->msb_delta = (int)tp->t_agcount_delta;
+ msbp++;
+ }
+ if (tp->t_imaxpct_delta != 0) {
+ msbp->msb_field = XFS_SBS_IMAX_PCT;
+ msbp->msb_delta = (int)tp->t_imaxpct_delta;
+ msbp++;
+ }
+ if (tp->t_rextsize_delta != 0) {
+ msbp->msb_field = XFS_SBS_REXTSIZE;
+ msbp->msb_delta = (int)tp->t_rextsize_delta;
+ msbp++;
+ }
+ if (tp->t_rbmblocks_delta != 0) {
+ msbp->msb_field = XFS_SBS_RBMBLOCKS;
+ msbp->msb_delta = (int)tp->t_rbmblocks_delta;
+ msbp++;
+ }
+ if (tp->t_rblocks_delta != 0) {
+ msbp->msb_field = XFS_SBS_RBLOCKS;
+ msbp->msb_delta = (int)tp->t_rblocks_delta;
+ msbp++;
+ }
+ if (tp->t_rextents_delta != 0) {
+ msbp->msb_field = XFS_SBS_REXTENTS;
+ msbp->msb_delta = (int)tp->t_rextents_delta;
+ msbp++;
+ }
+ if (tp->t_rextslog_delta != 0) {
+ msbp->msb_field = XFS_SBS_REXTSLOG;
+ msbp->msb_delta = (int)tp->t_rextslog_delta;
+ msbp++;
+ }
+ }
+
+ /*
+ * If we need to change anything, do it.
+ */
+ if (msbp > msb) {
+ error = xfs_mod_incore_sb_batch(tp->t_mountp, msb,
+ (uint)(msbp - msb), rsvd);
+ ASSERT(error == 0);
+ }
+}
+
+
+/*
+ * xfs_trans_commit
+ *
+ * Commit the given transaction to the log a/synchronously.
+ *
+ * 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.
+ */
+ /*ARGSUSED*/
+int
+xfs_trans_commit(
+ xfs_trans_t *tp,
+ uint flags,
+ xfs_lsn_t *commit_lsn_p)
+{
+ xfs_log_iovec_t *log_vector;
+ int nvec;
+ xfs_mount_t *mp;
+ xfs_lsn_t commit_lsn;
+ /* REFERENCED */
+ int error;
+ int log_flags;
+ int sync;
+#define XFS_TRANS_LOGVEC_COUNT 16
+ xfs_log_iovec_t log_vector_fast[XFS_TRANS_LOGVEC_COUNT];
+#if defined(XLOG_NOLOG) || defined(DEBUG)
+ static xfs_lsn_t trans_lsn = 1;
+#endif
+ void *commit_iclog;
+ int shutdown;
+
+ commit_lsn = -1;
+
+ /*
+ * Determine whether this commit is releasing a permanent
+ * log reservation or not.
+ */
+ if (flags & XFS_TRANS_RELEASE_LOG_RES) {
+ ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
+ log_flags = XFS_LOG_REL_PERM_RESERV;
+ } else {
+ log_flags = 0;
+ }
+ mp = tp->t_mountp;
+
+ /*
+ * 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.
+ */
+shut_us_down:
+ shutdown = XFS_FORCED_SHUTDOWN(mp) ? EIO : 0;
+ if (!(tp->t_flags & XFS_TRANS_DIRTY) || shutdown) {
+ 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(mp, tp);
+ if (tp->t_ticket) {
+ commit_lsn = xfs_log_done(mp, tp->t_ticket,
+ NULL, log_flags);
+ if (commit_lsn == -1 && !shutdown)
+ shutdown = XFS_ERROR(EIO);
+ }
+ PFLAGS_RESTORE_FSTRANS(&tp->t_pflags);
+ xfs_trans_free_items(tp, shutdown? XFS_TRANS_ABORT : 0);
+ xfs_trans_free_busy(tp);
+ xfs_trans_free(tp);
+ XFS_STATS_INC(xs_trans_empty);
+ if (commit_lsn_p)
+ *commit_lsn_p = commit_lsn;
+ return (shutdown);
+ }
+#if defined(XLOG_NOLOG) || defined(DEBUG)
+ ASSERT(!xlog_debug || tp->t_ticket != NULL);
+#else
+ ASSERT(tp->t_ticket != NULL);
+#endif
+
+ /*
+ * 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(mp, tp);
+
+ /*
+ * Ask each log item how many log_vector entries it will
+ * need so we can figure out how many to allocate.
+ * Try to avoid the kmem_alloc() call in the common case
+ * by using a vector from the stack when it fits.
+ */
+ nvec = xfs_trans_count_vecs(tp);
+
+ if (nvec == 0) {
+ xfs_force_shutdown(mp, XFS_LOG_IO_ERROR);
+ goto shut_us_down;
+ }
+
+
+ if (nvec <= XFS_TRANS_LOGVEC_COUNT) {
+ log_vector = log_vector_fast;
+ } else {
+ log_vector = (xfs_log_iovec_t *)kmem_alloc(nvec *
+ sizeof(xfs_log_iovec_t),
+ KM_SLEEP);
+ }
+
+ /*
+ * Fill in the log_vector and pin the logged items, and
+ * then write the transaction to the log.
+ */
+ xfs_trans_fill_vecs(tp, log_vector);
+
+ /*
+ * Ignore errors here. xfs_log_done would do the right thing.
+ * We need to put the ticket, etc. away.
+ */
+ error = xfs_log_write(mp, log_vector, nvec, tp->t_ticket,
+ &(tp->t_lsn));
+
+#if defined(XLOG_NOLOG) || defined(DEBUG)
+ if (xlog_debug) {
+ commit_lsn = xfs_log_done(mp, tp->t_ticket,
+ &commit_iclog, log_flags);
+ } else {
+ commit_lsn = 0;
+ tp->t_lsn = trans_lsn++;
+ }
+#else
+ /*
+ * This is the regular case. At this point (after the call finishes),
+ * the transaction is committed incore and could go out to disk at
+ * any time. However, all the items associated with the transaction
+ * are still locked and pinned in memory.
+ */
+ commit_lsn = xfs_log_done(mp, tp->t_ticket, &commit_iclog, log_flags);
+#endif
+
+ tp->t_commit_lsn = commit_lsn;
+ if (nvec > XFS_TRANS_LOGVEC_COUNT) {
+ kmem_free(log_vector, nvec * sizeof(xfs_log_iovec_t));
+ }
+
+ if (commit_lsn_p)
+ *commit_lsn_p = commit_lsn;
+
+ /*
+ * If we got a log write error. Unpin the logitems that we
+ * had pinned, clean up, free trans structure, and return error.
+ */
+ if (error || commit_lsn == -1) {
+ PFLAGS_RESTORE_FSTRANS(&tp->t_pflags);
+ xfs_trans_uncommit(tp, flags|XFS_TRANS_ABORT);
+ return XFS_ERROR(EIO);
+ }
+
+ /*
+ * Once the transaction has committed, unused
+ * reservations need to be released and changes to
+ * the superblock need to be reflected in the in-core
+ * version. Do that now.
+ */
+ xfs_trans_unreserve_and_mod_sb(tp);
+
+ sync = tp->t_flags & XFS_TRANS_SYNC;
+
+ /*
+ * Tell the LM to call the transaction completion routine
+ * when the log write with LSN commit_lsn completes (e.g.
+ * when the transaction commit really hits the on-disk log).
+ * After this call we cannot reference tp, because the call
+ * can happen at any time and the call will free the transaction
+ * structure pointed to by tp. The only case where we call
+ * the completion routine (xfs_trans_committed) directly is
+ * if the log is turned off on a debug kernel or we're
+ * running in simulation mode (the log is explicitly turned
+ * off).
+ */
+ tp->t_logcb.cb_func = (void(*)(void*, int))xfs_trans_committed;
+ tp->t_logcb.cb_arg = tp;
+
+ /*
+ * We need to pass the iclog buffer which was used for the
+ * transaction commit record into this function, and attach
+ * the callback to it. The callback must be attached before
+ * the items are unlocked to avoid racing with other threads
+ * waiting for an item to unlock.
+ */
+ shutdown = xfs_log_notify(mp, commit_iclog, &(tp->t_logcb));
+
+ /*
+ * Mark this thread as no longer being in a transaction
+ */
+ PFLAGS_RESTORE_FSTRANS(&tp->t_pflags);
+
+ /*
+ * Once all the items of the transaction have been copied
+ * to the in core log and the callback is attached, the
+ * items can be unlocked.
+ *
+ * This will free descriptors pointing to items which were
+ * not logged since there is nothing more to do with them.
+ * For items which were logged, we will keep pointers to them
+ * so they can be unpinned after the transaction commits to disk.
+ * This will also stamp each modified meta-data item with
+ * the commit lsn of this transaction for dependency tracking
+ * purposes.
+ */
+ xfs_trans_unlock_items(tp, commit_lsn);
+
+ /*
+ * If we detected a log error earlier, finish committing
+ * the transaction now (unpin log items, etc).
+ *
+ * Order is critical here, to avoid using the transaction
+ * pointer after its been freed (by xfs_trans_committed
+ * either here now, or as a callback). We cannot do this
+ * step inside xfs_log_notify as was done earlier because
+ * of this issue.
+ */
+ if (shutdown)
+ xfs_trans_committed(tp, XFS_LI_ABORTED);
+
+ /*
+ * Now that the xfs_trans_committed callback has been attached,
+ * and the items are released we can finally allow the iclog to
+ * go to disk.
+ */
+ error = xfs_log_release_iclog(mp, commit_iclog);
+
+ /*
+ * If the transaction needs to be synchronous, then force the
+ * log out now and wait for it.
+ */
+ if (sync) {
+ if (!error)
+ error = xfs_log_force(mp, commit_lsn,
+ XFS_LOG_FORCE | XFS_LOG_SYNC);
+ XFS_STATS_INC(xs_trans_sync);
+ } else {
+ XFS_STATS_INC(xs_trans_async);
+ }
+
+ return (error);
+}
+
+
+/*
+ * Total up the number of log iovecs needed to commit this
+ * transaction. The transaction itself needs one for the
+ * transaction header. Ask each dirty item in turn how many
+ * it needs to get the total.
+ */
+STATIC uint
+xfs_trans_count_vecs(
+ xfs_trans_t *tp)
+{
+ int nvecs;
+ xfs_log_item_desc_t *lidp;
+
+ nvecs = 1;
+ lidp = xfs_trans_first_item(tp);
+ ASSERT(lidp != NULL);
+
+ /* In the non-debug case we need to start bailing out if we
+ * didn't find a log_item here, return zero and let trans_commit
+ * deal with it.
+ */
+ if (lidp == NULL)
+ return 0;
+
+ while (lidp != NULL) {
+ /*
+ * Skip items which aren't dirty in this transaction.
+ */
+ if (!(lidp->lid_flags & XFS_LID_DIRTY)) {
+ lidp = xfs_trans_next_item(tp, lidp);
+ continue;
+ }
+ lidp->lid_size = IOP_SIZE(lidp->lid_item);
+ nvecs += lidp->lid_size;
+ lidp = xfs_trans_next_item(tp, lidp);
+ }
+
+ return nvecs;
+}
+
+/*
+ * Called from the trans_commit code when we notice that
+ * the filesystem is in the middle of a forced shutdown.
+ */
+STATIC void
+xfs_trans_uncommit(
+ xfs_trans_t *tp,
+ uint flags)
+{
+ xfs_log_item_desc_t *lidp;
+
+ for (lidp = xfs_trans_first_item(tp);
+ lidp != NULL;
+ lidp = xfs_trans_next_item(tp, lidp)) {
+ /*
+ * Unpin all but those that aren't dirty.
+ */
+ if (lidp->lid_flags & XFS_LID_DIRTY)
+ IOP_UNPIN_REMOVE(lidp->lid_item, tp);
+ }
+
+ xfs_trans_unreserve_and_mod_sb(tp);
+ XFS_TRANS_UNRESERVE_AND_MOD_DQUOTS(tp->t_mountp, tp);
+
+ xfs_trans_free_items(tp, flags);
+ xfs_trans_free_busy(tp);
+ xfs_trans_free(tp);
+}
+
+/*
+ * Fill in the vector with pointers to data to be logged
+ * by this transaction. The transaction header takes
+ * the first vector, and then each dirty item takes the
+ * number of vectors it indicated it needed in xfs_trans_count_vecs().
+ *
+ * As each item fills in the entries it needs, also pin the item
+ * so that it cannot be flushed out until the log write completes.
+ */
+STATIC void
+xfs_trans_fill_vecs(
+ xfs_trans_t *tp,
+ xfs_log_iovec_t *log_vector)
+{
+ xfs_log_item_desc_t *lidp;
+ xfs_log_iovec_t *vecp;
+ uint nitems;
+
+ /*
+ * Skip over the entry for the transaction header, we'll
+ * fill that in at the end.
+ */
+ vecp = log_vector + 1; /* pointer arithmetic */
+
+ nitems = 0;
+ lidp = xfs_trans_first_item(tp);
+ ASSERT(lidp != NULL);
+ while (lidp != NULL) {
+ /*
+ * Skip items which aren't dirty in this transaction.
+ */
+ if (!(lidp->lid_flags & XFS_LID_DIRTY)) {
+ lidp = xfs_trans_next_item(tp, lidp);
+ continue;
+ }
+ /*
+ * The item may be marked dirty but not log anything.
+ * This can be used to get called when a transaction
+ * is committed.
+ */
+ if (lidp->lid_size) {
+ nitems++;
+ }
+ IOP_FORMAT(lidp->lid_item, vecp);
+ vecp += lidp->lid_size; /* pointer arithmetic */
+ IOP_PIN(lidp->lid_item);
+ lidp = xfs_trans_next_item(tp, lidp);
+ }
+
+ /*
+ * Now that we've counted the number of items in this
+ * transaction, fill in the transaction header.
+ */
+ tp->t_header.th_magic = XFS_TRANS_HEADER_MAGIC;
+ tp->t_header.th_type = tp->t_type;
+ tp->t_header.th_num_items = nitems;
+ log_vector->i_addr = (xfs_caddr_t)&tp->t_header;
+ log_vector->i_len = sizeof(xfs_trans_header_t);
+}
+
+
+/*
+ * 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(
+ xfs_trans_t *tp,
+ int flags)
+{
+ int log_flags;
+#ifdef DEBUG
+ xfs_log_item_chunk_t *licp;
+ xfs_log_item_desc_t *lidp;
+ xfs_log_item_t *lip;
+ int i;
+#endif
+
+ /*
+ * See if the caller is being too lazy to figure out if
+ * the transaction really needs an abort.
+ */
+ if ((flags & XFS_TRANS_ABORT) && !(tp->t_flags & XFS_TRANS_DIRTY))
+ flags &= ~XFS_TRANS_ABORT;
+ /*
+ * 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 ((tp->t_flags & XFS_TRANS_DIRTY) &&
+ !XFS_FORCED_SHUTDOWN(tp->t_mountp))
+ xfs_force_shutdown(tp->t_mountp, XFS_CORRUPT_INCORE);
+#ifdef DEBUG
+ if (!(flags & XFS_TRANS_ABORT)) {
+ licp = &(tp->t_items);
+ while (licp != NULL) {
+ lidp = licp->lic_descs;
+ for (i = 0; i < licp->lic_unused; i++, lidp++) {
+ if (XFS_LIC_ISFREE(licp, i)) {
+ continue;
+ }
+
+ lip = lidp->lid_item;
+ if (!XFS_FORCED_SHUTDOWN(tp->t_mountp))
+ ASSERT(!(lip->li_type == XFS_LI_EFD));
+ }
+ licp = licp->lic_next;
+ }
+ }
+#endif
+ xfs_trans_unreserve_and_mod_sb(tp);
+ XFS_TRANS_UNRESERVE_AND_MOD_DQUOTS(tp->t_mountp, tp);
+
+ if (tp->t_ticket) {
+ if (flags & XFS_TRANS_RELEASE_LOG_RES) {
+ ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
+ log_flags = XFS_LOG_REL_PERM_RESERV;
+ } else {
+ log_flags = 0;
+ }
+ xfs_log_done(tp->t_mountp, tp->t_ticket, NULL, log_flags);
+ }
+
+ /* mark this thread as no longer being in a transaction */
+ PFLAGS_RESTORE_FSTRANS(&tp->t_pflags);
+
+ xfs_trans_free_items(tp, flags);
+ xfs_trans_free_busy(tp);
+ xfs_trans_free(tp);
+}
+
+
+/*
+ * 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(
+ xfs_trans_t *tp)
+{
+ atomic_dec(&tp->t_mountp->m_active_trans);
+ XFS_TRANS_FREE_DQINFO(tp->t_mountp, tp);
+ kmem_zone_free(xfs_trans_zone, tp);
+}
+
+
+/*
+ * THIS SHOULD BE REWRITTEN TO USE xfs_trans_next_item().
+ *
+ * This is typically called by the LM when a transaction has been fully
+ * committed to disk. It needs to unpin the items which have
+ * been logged by the transaction and update their positions
+ * in the AIL if necessary.
+ * This also gets called when the transactions didn't get written out
+ * because of an I/O error. Abortflag & XFS_LI_ABORTED is set then.
+ *
+ * Call xfs_trans_chunk_committed() to process the items in
+ * each chunk.
+ */
+STATIC void
+xfs_trans_committed(
+ xfs_trans_t *tp,
+ int abortflag)
+{
+ xfs_log_item_chunk_t *licp;
+ xfs_log_item_chunk_t *next_licp;
+ xfs_log_busy_chunk_t *lbcp;
+ xfs_log_busy_slot_t *lbsp;
+ int i;
+
+ /*
+ * Call the transaction's completion callback if there
+ * is one.
+ */
+ if (tp->t_callback != NULL) {
+ tp->t_callback(tp, tp->t_callarg);
+ }
+
+ /*
+ * Special case the chunk embedded in the transaction.
+ */
+ licp = &(tp->t_items);
+ if (!(XFS_LIC_ARE_ALL_FREE(licp))) {
+ xfs_trans_chunk_committed(licp, tp->t_lsn, abortflag);
+ }
+
+ /*
+ * Process the items in each chunk in turn.
+ */
+ licp = licp->lic_next;
+ while (licp != NULL) {
+ ASSERT(!XFS_LIC_ARE_ALL_FREE(licp));
+ xfs_trans_chunk_committed(licp, tp->t_lsn, abortflag);
+ next_licp = licp->lic_next;
+ kmem_free(licp, sizeof(xfs_log_item_chunk_t));
+ licp = next_licp;
+ }
+
+ /*
+ * Clear all the per-AG busy list items listed in this transaction
+ */
+ lbcp = &tp->t_busy;
+ while (lbcp != NULL) {
+ for (i = 0, lbsp = lbcp->lbc_busy; i < lbcp->lbc_unused; i++, lbsp++) {
+ if (!XFS_LBC_ISFREE(lbcp, i)) {
+ xfs_alloc_clear_busy(tp, lbsp->lbc_ag,
+ lbsp->lbc_idx);
+ }
+ }
+ lbcp = lbcp->lbc_next;
+ }
+ xfs_trans_free_busy(tp);
+
+ /*
+ * That's it for the transaction structure. Free it.
+ */
+ xfs_trans_free(tp);
+}
+
+/*
+ * This is called to perform the commit processing for each
+ * item described by the given chunk.
+ *
+ * The commit processing consists of unlocking items which were
+ * held locked with the SYNC_UNLOCK attribute, calling the committed
+ * routine of each logged item, updating the item's position in the AIL
+ * if necessary, and unpinning each item. If the committed routine
+ * returns -1, then do nothing further with the item because it
+ * may have been freed.
+ *
+ * Since items are unlocked when they are copied to the incore
+ * log, it is possible for two transactions to be completing
+ * and manipulating the same item simultaneously. The AIL lock
+ * will protect the lsn field of each item. The value of this
+ * field can never go backwards.
+ *
+ * We unpin the items after repositioning them in the AIL, because
+ * otherwise they could be immediately flushed and we'd have to race
+ * with the flusher trying to pull the item from the AIL as we add it.
+ */
+STATIC void
+xfs_trans_chunk_committed(
+ xfs_log_item_chunk_t *licp,
+ xfs_lsn_t lsn,
+ int aborted)
+{
+ xfs_log_item_desc_t *lidp;
+ xfs_log_item_t *lip;
+ xfs_lsn_t item_lsn;
+ struct xfs_mount *mp;
+ int i;
+ SPLDECL(s);
+
+ lidp = licp->lic_descs;
+ for (i = 0; i < licp->lic_unused; i++, lidp++) {
+ if (XFS_LIC_ISFREE(licp, i)) {
+ continue;
+ }
+
+ lip = lidp->lid_item;
+ if (aborted)
+ lip->li_flags |= XFS_LI_ABORTED;
+
+ /*
+ * Send in the ABORTED flag to the COMMITTED routine
+ * so that it knows whether the transaction was aborted
+ * or not.
+ */
+ item_lsn = IOP_COMMITTED(lip, lsn);
+
+ /*
+ * If the committed routine returns -1, make
+ * no more references to the item.
+ */
+ if (XFS_LSN_CMP(item_lsn, (xfs_lsn_t)-1) == 0) {
+ continue;
+ }
+
+ /*
+ * If the returned lsn is greater than what it
+ * contained before, update the location of the
+ * item in the AIL. If it is not, then do nothing.
+ * Items can never move backwards in the AIL.
+ *
+ * While the new lsn should usually be greater, it
+ * is possible that a later transaction completing
+ * simultaneously with an earlier one using the
+ * same item could complete first with a higher lsn.
+ * This would cause the earlier transaction to fail
+ * the test below.
+ */
+ mp = lip->li_mountp;
+ AIL_LOCK(mp,s);
+ if (XFS_LSN_CMP(item_lsn, lip->li_lsn) > 0) {
+ /*
+ * This will set the item's lsn to item_lsn
+ * and update the position of the item in
+ * the AIL.
+ *
+ * xfs_trans_update_ail() drops the AIL lock.
+ */
+ xfs_trans_update_ail(mp, lip, item_lsn, s);
+ } else {
+ AIL_UNLOCK(mp, s);
+ }
+
+ /*
+ * Now that we've repositioned the item in the AIL,
+ * unpin it so it can be flushed. Pass information
+ * about buffer stale state down from the log item
+ * flags, if anyone else stales the buffer we do not
+ * want to pay any attention to it.
+ */
+ IOP_UNPIN(lip, lidp->lid_flags & XFS_LID_BUF_STALE);
+ }
+}
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