xfs: refactor delalloc accounting in xfs_bmap_add_extent_delay_real

Account for all changes to the delalloc reservation in da_new, and use a
single call xfs_mod_fdblocks to reserve/free blocks, including always
checking for an error.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 390f12d3c5d286af95108f0703577cef38aa5bb4..6ca185dbd764589d17e4a4ccecab750fd9408069 100644 (file)
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -1574,7 +1574,6 @@ xfs_bmap_add_extent_delay_real(
        int                     whichfork)
 {
        struct xfs_bmbt_irec    *new = &bma->got;
-       int                     diff;   /* temp value */
        int                     error;  /* error return value */
        int                     i;      /* temp state */
        xfs_ifork_t             *ifp;   /* inode fork pointer */
@@ -2072,17 +2071,6 @@ xfs_bmap_add_extent_delay_real(
 
                da_new = startblockval(PREV.br_startblock) +
                         startblockval(RIGHT.br_startblock);
-               diff = da_new - startblockval(old.br_startblock);
-               if (bma->cur)
-                       diff += bma->cur->bc_private.b.allocated;
-               if (diff > 0) {
-                       error = xfs_mod_fdblocks(bma->ip->i_mount,
-                                                -((int64_t)diff), false);
-                       ASSERT(!error);
-                       if (error)
-                               goto done;
-               }
-
                bma->idx++;
                break;
 
@@ -2117,19 +2105,17 @@ xfs_bmap_add_extent_delay_real(
                        goto done;
        }
 
-       /* adjust for changes in reserved delayed indirect blocks */
-       if (da_old || da_new) {
-               temp = da_new;
-               if (bma->cur)
-                       temp += bma->cur->bc_private.b.allocated;
-               if (temp < da_old)
-                       xfs_mod_fdblocks(bma->ip->i_mount,
-                                       (int64_t)(da_old - temp), false);
+       if (bma->cur) {
+               da_new += bma->cur->bc_private.b.allocated;
+               bma->cur->bc_private.b.allocated = 0;
        }
 
-       /* clear out the allocated field, done with it now in any case. */
-       if (bma->cur)
-               bma->cur->bc_private.b.allocated = 0;
+       /* adjust for changes in reserved delayed indirect blocks */
+       if (da_new != da_old) {
+               ASSERT(state == 0 || da_new < da_old);
+               error = xfs_mod_fdblocks(mp, (int64_t)(da_old - da_new),
+                               false);
+       }
 
        xfs_bmap_check_leaf_extents(bma->cur, bma->ip, whichfork);
 done: