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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
  * Copyright (C) 2010 Red Hat, Inc.
  * All Rights Reserved.
  */
 #include "xfs.h"
 #include "xfs_fs.h"
 #include "xfs_shared.h"
 #include "xfs_format.h"
 #include "xfs_log_format.h"
 #include "xfs_trans_resv.h"
 #include "xfs_mount.h"
 #include "xfs_extent_busy.h"
 #include "xfs_quota.h"
 #include "xfs_trans.h"
 #include "xfs_trans_priv.h"
 #include "xfs_log.h"
 #include "xfs_log_priv.h"
 #include "xfs_trace.h"
 #include "xfs_error.h"
 #include "xfs_defer.h"
 #include "xfs_inode.h"
 #include "xfs_dquot_item.h"
 #include "xfs_dquot.h"
 #include "xfs_icache.h"
 
 struct kmem_cache   *xfs_trans_cache;
 
 #if defined(CONFIG_TRACEPOINTS)
 static void
 xfs_trans_trace_reservations(
     struct xfs_mount    *mp)
 {
     struct xfs_trans_res    *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_firstblock = NULLFSBLOCK;
 
     ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
     ASSERT(tp->t_ticket != NULL);
 
     ntp->t_flags = XFS_TRANS_PERM_LOG_RES |
                (tp->t_flags & XFS_TRANS_RESERVE) |
                (tp->t_flags & XFS_TRANS_NO_WRITECOUNT) |
                (tp->t_flags & XFS_TRANS_RES_FDBLKS);
     /* We gave our writer reference to the new transaction */
     tp->t_flags |= XFS_TRANS_NO_WRITECOUNT;
     ntp->t_ticket = xfs_log_ticket_get(tp->t_ticket);
 
     ASSERT(tp->t_blk_res >= tp->t_blk_res_used);
     ntp->t_blk_res = tp->t_blk_res - tp->t_blk_res_used;
     tp->t_blk_res = tp->t_blk_res_used;
 
     ntp->t_rtx_res = tp->t_rtx_res - tp->t_rtx_res_used;
     tp->t_rtx_res = tp->t_rtx_res_used;
 
     xfs_trans_switch_context(tp, ntp);
 
     /* move deferred ops over to the new tp */
     xfs_defer_move(ntp, tp);
 
     xfs_trans_dup_dqinfo(tp, ntp);
     return ntp;
 }
 
 /*
  * This is called to reserve free disk blocks and log space for the
  * given transaction.  This must be done before allocating any resources
  * within the transaction.
  *
  * This will return ENOSPC if there are not enough blocks available.
  * It will sleep waiting for available log space.
  * The only valid value for the flags parameter is XFS_RES_LOG_PERM, which
  * is used by long running transactions.  If any one of the reservations
  * fails then they will all be backed out.
  *
  * This does not do quota reservations. That typically is done by the
  * caller afterwards.
  */
 static int
 xfs_trans_reserve(
     struct xfs_trans    *tp,
     struct xfs_trans_res    *resp,
     uint            blocks,
     uint            rtextents)
 {
     struct xfs_mount    *mp = tp->t_mountp;
     int         error = 0;
     bool            rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
 
     /*
      * Attempt to reserve the needed disk blocks by decrementing
      * the number needed from the number available.  This will
      * fail if the count would go below zero.
      */
     if (blocks > 0) {
         error = xfs_mod_fdblocks(mp, -((int64_t)blocks), rsvd);
         if (error != 0)
             return -ENOSPC;
         tp->t_blk_res += blocks;
     }
 
     /*
      * Reserve the log space needed for this transaction.
      */
     if (resp->tr_logres > 0) {
         bool    permanent = false;
 
         ASSERT(tp->t_log_res == 0 ||
                tp->t_log_res == resp->tr_logres);
         ASSERT(tp->t_log_count == 0 ||
                tp->t_log_count == resp->tr_logcount);
 
         if (resp->tr_logflags & XFS_TRANS_PERM_LOG_RES) {
             tp->t_flags |= XFS_TRANS_PERM_LOG_RES;
             permanent = true;
         } else {
             ASSERT(tp->t_ticket == NULL);
             ASSERT(!(tp->t_flags & XFS_TRANS_PERM_LOG_RES));
         }
 
         if (tp->t_ticket != NULL) {
             ASSERT(resp->tr_logflags & XFS_TRANS_PERM_LOG_RES);
             error = xfs_log_regrant(mp, tp->t_ticket);
         } else {
             error = xfs_log_reserve(mp, resp->tr_logres,
                         resp->tr_logcount,
                         &tp->t_ticket, permanent);
         }
 
         if (error)
             goto undo_blocks;
 
         tp->t_log_res = resp->tr_logres;
         tp->t_log_count = resp->tr_logcount;
     }
 
     /*
      * Attempt to reserve the needed realtime extents by decrementing
      * the number needed from the number available.  This will
      * fail if the count would go below zero.
      */
     if (rtextents > 0) {
         error = xfs_mod_frextents(mp, -((int64_t)rtextents));
         if (error) {
             error = -ENOSPC;
             goto undo_log;
         }
         tp->t_rtx_res += rtextents;
     }
 
     return 0;
 
     /*
      * Error cases jump to one of these labels to undo any
      * reservations which have already been performed.
      */
 undo_log:
     if (resp->tr_logres > 0) {
         xfs_log_ticket_ungrant(mp->m_log, tp->t_ticket);
         tp->t_ticket = NULL;
         tp->t_log_res = 0;
         tp->t_flags &= ~XFS_TRANS_PERM_LOG_RES;
     }
 
 undo_blocks:
     if (blocks > 0) {
         xfs_mod_fdblocks(mp, (int64_t)blocks, rsvd);
         tp->t_blk_res = 0;
     }
     return error;
 }
 
 int
 xfs_trans_alloc(
     struct xfs_mount    *mp,
     struct xfs_trans_res    *resp,
     uint            blocks,
     uint            rtextents,
     uint            flags,
     struct xfs_trans    **tpp)
 {
     struct xfs_trans    *tp;
     bool            want_retry = true;
     int         error;
 
     /*
      * Allocate the handle before we do our freeze accounting and setting up
      * GFP_NOFS allocation context so that we avoid lockdep false positives
      * by doing GFP_KERNEL allocations inside sb_start_intwrite().
      */
 retry:
     tp = kmem_cache_zalloc(xfs_trans_cache, GFP_KERNEL | __GFP_NOFAIL);
     if (!(flags & XFS_TRANS_NO_WRITECOUNT))
         sb_start_intwrite(mp->m_super);
     xfs_trans_set_context(tp);
 
     /*
      * Zero-reservation ("empty") transactions can't modify anything, so
      * they're allowed to run while we're frozen.
      */
     WARN_ON(resp->tr_logres > 0 &&
         mp->m_super->s_writers.frozen == SB_FREEZE_COMPLETE);
     ASSERT(!(flags & XFS_TRANS_RES_FDBLKS) ||
            xfs_has_lazysbcount(mp));
 
     tp->t_magic = XFS_TRANS_HEADER_MAGIC;
     tp->t_flags = flags;
     tp->t_mountp = mp;
     INIT_LIST_HEAD(&tp->t_items);
     INIT_LIST_HEAD(&tp->t_busy);
     INIT_LIST_HEAD(&tp->t_dfops);
     tp->t_firstblock = NULLFSBLOCK;
 
     error = xfs_trans_reserve(tp, resp, blocks, rtextents);
     if (error == -ENOSPC && want_retry) {
         xfs_trans_cancel(tp);
 
         /*
          * We weren't able to reserve enough space for the transaction.
          * Flush the other speculative space allocations to free space.
          * Do not perform a synchronous scan because callers can hold
          * other locks.
          */
         xfs_blockgc_flush_all(mp);
         want_retry = false;
         goto retry;
     }
     if (error) {
         xfs_trans_cancel(tp);
         return error;
     }
 
     trace_xfs_trans_alloc(tp, _RET_IP_);
 
     *tpp = tp;
     return 0;
 }
 
 /*
  * Create an empty transaction with no reservation.  This is a defensive
  * mechanism for routines that query metadata without actually modifying them --
  * if the metadata being queried is somehow cross-linked (think a btree block
  * pointer that points higher in the tree), we risk deadlock.  However, blocks
  * grabbed as part of a transaction can be re-grabbed.  The verifiers will
  * notice the corrupt block and the operation will fail back to userspace
  * without deadlocking.
  *
  * Note the zero-length reservation; this transaction MUST be cancelled without
  * any dirty data.
  *
  * Callers should obtain freeze protection to avoid a conflict with fs freezing
  * where we can be grabbing buffers at the same time that freeze is trying to
  * drain the buffer LRU list.
  */
 int
 xfs_trans_alloc_empty(
     struct xfs_mount        *mp,
     struct xfs_trans        **tpp)
 {
     struct xfs_trans_res        resv = {0};
 
     return xfs_trans_alloc(mp, &resv, 0, 0, XFS_TRANS_NO_WRITECOUNT, tpp);
 }
 
 /*
  * Record the indicated change to the given field for application
  * to the file system's superblock when the transaction commits.
  * For now, just store the change in the transaction structure.
  *
  * Mark the transaction structure to indicate that the superblock
  * needs to be updated before committing.
  *
  * Because we may not be keeping track of allocated/free inodes and
  * used filesystem blocks in the superblock, we do not mark the
  * superblock dirty in this transaction if we modify these fields.
  * We still need to update the transaction deltas so that they get
  * applied to the incore superblock, but we don't want them to
  * cause the superblock to get locked and logged if these are the
  * only fields in the superblock that the transaction modifies.
  */
 void
 xfs_trans_mod_sb(
     xfs_trans_t *tp,
     uint        field,
     int64_t     delta)
 {
     uint32_t    flags = (XFS_TRANS_DIRTY|XFS_TRANS_SB_DIRTY);
     xfs_mount_t *mp = tp->t_mountp;
 
     switch (field) {
     case XFS_TRANS_SB_ICOUNT:
         tp->t_icount_delta += delta;
         if (xfs_has_lazysbcount(mp))
             flags &= ~XFS_TRANS_SB_DIRTY;
         break;
     case XFS_TRANS_SB_IFREE:
         tp->t_ifree_delta += delta;
         if (xfs_has_lazysbcount(mp))
             flags &= ~XFS_TRANS_SB_DIRTY;
         break;
     case XFS_TRANS_SB_FDBLOCKS:
         /*
          * Track the number of blocks allocated in the transaction.
          * Make sure it does not exceed the number reserved. If so,
          * shutdown as this can lead to accounting inconsistency.
          */
         if (delta < 0) {
             tp->t_blk_res_used += (uint)-delta;
             if (tp->t_blk_res_used > tp->t_blk_res)
                 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
         } else if (delta > 0 && (tp->t_flags & XFS_TRANS_RES_FDBLKS)) {
             int64_t blkres_delta;
 
             /*
              * Return freed blocks directly to the reservation
              * instead of the global pool, being careful not to
              * overflow the trans counter. This is used to preserve
              * reservation across chains of transaction rolls that
              * repeatedly free and allocate blocks.
              */
             blkres_delta = min_t(int64_t, delta,
                          UINT_MAX - tp->t_blk_res);
             tp->t_blk_res += blkres_delta;
             delta -= blkres_delta;
         }
         tp->t_fdblocks_delta += delta;
         if (xfs_has_lazysbcount(mp))
             flags &= ~XFS_TRANS_SB_DIRTY;
         break;
     case XFS_TRANS_SB_RES_FDBLOCKS:
         /*
          * The allocation has already been applied to the
          * in-core superblock's counter.  This should only
          * be applied to the on-disk superblock.
          */
         tp->t_res_fdblocks_delta += delta;
         if (xfs_has_lazysbcount(mp))
             flags &= ~XFS_TRANS_SB_DIRTY;
         break;
     case XFS_TRANS_SB_FREXTENTS:
         /*
          * Track the number of blocks allocated in the
          * transaction.  Make sure it does not exceed the
          * number reserved.
          */
         if (delta < 0) {
             tp->t_rtx_res_used += (uint)-delta;
             ASSERT(tp->t_rtx_res_used <= tp->t_rtx_res);
         }
         tp->t_frextents_delta += delta;
         break;
     case XFS_TRANS_SB_RES_FREXTENTS:
         /*
          * The allocation has already been applied to the
          * in-core superblock's counter.  This should only
          * be applied to the on-disk superblock.
          */
         ASSERT(delta < 0);
         tp->t_res_frextents_delta += delta;
         break;
     case XFS_TRANS_SB_DBLOCKS:
         tp->t_dblocks_delta += delta;
         break;
     case XFS_TRANS_SB_AGCOUNT:
         ASSERT(delta > 0);
         tp->t_agcount_delta += delta;
         break;
     case XFS_TRANS_SB_IMAXPCT:
         tp->t_imaxpct_delta += delta;
         break;
     case XFS_TRANS_SB_REXTSIZE:
         tp->t_rextsize_delta += delta;
         break;
     case XFS_TRANS_SB_RBMBLOCKS:
         tp->t_rbmblocks_delta += delta;
         break;
     case XFS_TRANS_SB_RBLOCKS:
         tp->t_rblocks_delta += delta;
         break;
     case XFS_TRANS_SB_REXTENTS:
         tp->t_rextents_delta += delta;
         break;
     case XFS_TRANS_SB_REXTSLOG:
         tp->t_rextslog_delta += delta;
         break;
     default:
         ASSERT(0);
         return;
     }
 
     tp->t_flags |= flags;
 }
 
 /*
  * xfs_trans_apply_sb_deltas() is called from the commit code
  * to bring the superblock buffer into the current transaction
  * and modify it as requested by earlier calls to xfs_trans_mod_sb().
  *
  * For now we just look at each field allowed to change and change
  * it if necessary.
  */
 STATIC void
 xfs_trans_apply_sb_deltas(
     xfs_trans_t *tp)
 {
     struct xfs_dsb  *sbp;
     struct xfs_buf  *bp;
     int     whole = 0;
 
     bp = xfs_trans_getsb(tp);
     sbp = bp->b_addr;
 
     /*
      * Only update the superblock counters if we are logging them
      */
     if (!xfs_has_lazysbcount((tp->t_mountp))) {
         if (tp->t_icount_delta)
             be64_add_cpu(&sbp->sb_icount, tp->t_icount_delta);
         if (tp->t_ifree_delta)
             be64_add_cpu(&sbp->sb_ifree, tp->t_ifree_delta);
         if (tp->t_fdblocks_delta)
             be64_add_cpu(&sbp->sb_fdblocks, tp->t_fdblocks_delta);
         if (tp->t_res_fdblocks_delta)
             be64_add_cpu(&sbp->sb_fdblocks, tp->t_res_fdblocks_delta);
     }
 
     /*
      * 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;
     bool            rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
     int64_t         blkdelta = 0;
     int64_t         rtxdelta = 0;
     int64_t         idelta = 0;
     int64_t         ifreedelta = 0;
     int         error;
 
     /* calculate deltas */
     if (tp->t_blk_res > 0)
         blkdelta = tp->t_blk_res;
     if ((tp->t_fdblocks_delta != 0) &&
         (xfs_has_lazysbcount(mp) ||
          (tp->t_flags & XFS_TRANS_SB_DIRTY)))
             blkdelta += tp->t_fdblocks_delta;
 
     if (tp->t_rtx_res > 0)
         rtxdelta = tp->t_rtx_res;
     if ((tp->t_frextents_delta != 0) &&
         (tp->t_flags & XFS_TRANS_SB_DIRTY))
         rtxdelta += tp->t_frextents_delta;
 
     if (xfs_has_lazysbcount(mp) ||
          (tp->t_flags & XFS_TRANS_SB_DIRTY)) {
         idelta = tp->t_icount_delta;
         ifreedelta = tp->t_ifree_delta;
     }
 
     /* apply the per-cpu counters */
     if (blkdelta) {
         error = xfs_mod_fdblocks(mp, blkdelta, rsvd);
         ASSERT(!error);
     }
 
     if (idelta)
         percpu_counter_add_batch(&mp->m_icount, idelta,
                      XFS_ICOUNT_BATCH);
 
     if (ifreedelta)
         percpu_counter_add(&mp->m_ifree, ifreedelta);
 
     if (rtxdelta) {
         error = xfs_mod_frextents(mp, rtxdelta);
         ASSERT(!error);
     }
 
     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;
     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_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);
     }
 }
 
 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 list_head    *lv_chain,
     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 */
     list_for_each_entry(lv, lv_chain, lv_list) {
         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(xlog_is_shutdown(ailp->ail_log));
             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);
 }
 
 /*
  * 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;
     }
 
     /*
      * 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.
      */
     if (!list_empty(&tp->t_dfops)) {
         ASSERT(xfs_is_shutdown(mp) || list_empty(&tp->t_dfops));
         ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
         dirty = true;
         xfs_defer_cancel(tp);
     }
 
     /*
      * See if the caller is relying on us to shut down the filesystem. 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,
             rblocks / mp->m_sb.sb_rextsize,
             force ? XFS_TRANS_RESERVE : 0, &tp);
     if (error)
         return error;
 
     xfs_ilock(ip, XFS_ILOCK_EXCL);
     xfs_trans_ijoin(tp, ip, 0);
 
     error = xfs_qm_dqattach_locked(ip, false);
     if (error) {
         /* Caller should have allocated the dquots! */
         ASSERT(error != -ENOENT);
         goto out_cancel;
     }
 
     error = xfs_trans_reserve_quota_nblks(tp, ip, dblocks, rblocks, force);
     if ((error == -EDQUOT || error == -ENOSPC) && !retried) {
         xfs_trans_cancel(tp);
         xfs_iunlock(ip, XFS_ILOCK_EXCL);
         xfs_blockgc_free_quota(ip, 0);
         retried = true;
         goto retry;
     }
     if (error)
         goto out_cancel;
 
     *tpp = tp;
     return 0;
 
 out_cancel:
     xfs_trans_cancel(tp);
     xfs_iunlock(ip, XFS_ILOCK_EXCL);
     return error;
 }
 
 /*
  * Allocate an transaction in preparation for inode creation by reserving quota
  * against the given dquots.  Callers are not required to hold any inode locks.
  */
 int
 xfs_trans_alloc_icreate(
     struct xfs_mount    *mp,
     struct xfs_trans_res    *resv,
     struct xfs_dquot    *udqp,
     struct xfs_dquot    *gdqp,
     struct xfs_dquot    *pdqp,
     unsigned int        dblocks,
     struct xfs_trans    **tpp)
 {
     struct xfs_trans    *tp;
     bool            retried = false;
     int         error;
 
 retry:
     error = xfs_trans_alloc(mp, resv, dblocks, 0, 0, &tp);
     if (error)
         return error;
 
     error = xfs_trans_reserve_quota_icreate(tp, udqp, gdqp, pdqp, dblocks);
     if ((error == -EDQUOT || error == -ENOSPC) && !retried) {
         xfs_trans_cancel(tp);
         xfs_blockgc_free_dquots(mp, udqp, gdqp, pdqp, 0);
         retried = true;
         goto retry;
     }
     if (error) {
         xfs_trans_cancel(tp);
         return error;
     }
 
     *tpp = tp;
     return 0;
 }
 
 /*
  * Allocate an transaction, lock and join the inode to it, and reserve quota
  * in preparation for inode attribute changes that include uid, gid, or prid
  * changes.
  *
  * The caller must ensure that the on-disk dquots attached to this inode have
  * already been allocated and initialized.  The ILOCK will be dropped when the
  * transaction is committed or cancelled.
  */
 int
 xfs_trans_alloc_ichange(
     struct xfs_inode    *ip,
     struct xfs_dquot    *new_udqp,
     struct xfs_dquot    *new_gdqp,
     struct xfs_dquot    *new_pdqp,
     bool            force,
     struct xfs_trans    **tpp)
 {
     struct xfs_trans    *tp;
     struct xfs_mount    *mp = ip->i_mount;
     struct xfs_dquot    *udqp;
     struct xfs_dquot    *gdqp;
     struct xfs_dquot    *pdqp;
     bool            retried = false;
     int         error;
 
 retry:
     error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ichange, 0, 0, 0, &tp);
     if (error)
         return error;
 
     xfs_ilock(ip, XFS_ILOCK_EXCL);
     xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 
     error = xfs_qm_dqattach_locked(ip, false);
     if (error) {
         /* Caller should have allocated the dquots! */
         ASSERT(error != -ENOENT);
         goto out_cancel;
     }
 
     /*
      * For each quota type, skip quota reservations if the inode's dquots
      * now match the ones that came from the caller, or the caller didn't
      * pass one in.  The inode's dquots can change if we drop the ILOCK to
      * perform a blockgc scan, so we must preserve the caller's arguments.
      */
     udqp = (new_udqp != ip->i_udquot) ? new_udqp : NULL;
     gdqp = (new_gdqp != ip->i_gdquot) ? new_gdqp : NULL;
     pdqp = (new_pdqp != ip->i_pdquot) ? new_pdqp : NULL;
     if (udqp || gdqp || pdqp) {
         unsigned int    qflags = XFS_QMOPT_RES_REGBLKS;
 
         if (force)
             qflags |= XFS_QMOPT_FORCE_RES;
 
         /*
          * Reserve enough quota to handle blocks on disk and reserved
          * for a delayed allocation.  We'll actually transfer the
          * delalloc reservation between dquots at chown time, even
          * though that part is only semi-transactional.
          */
         error = xfs_trans_reserve_quota_bydquots(tp, mp, udqp, gdqp,
                 pdqp, ip->i_nblocks + ip->i_delayed_blks,
                 1, qflags);
         if ((error == -EDQUOT || error == -ENOSPC) && !retried) {
             xfs_trans_cancel(tp);
             xfs_blockgc_free_dquots(mp, udqp, gdqp, pdqp, 0);
             retried = true;
             goto retry;
         }
         if (error)
             goto out_cancel;
     }
 
     *tpp = tp;
     return 0;
 
 out_cancel:
     xfs_trans_cancel(tp);
     return error;
 }
 
 /*
  * 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.
  */
 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, XFS_ILOCK_EXCL);
     xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 
     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_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;
 }

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