1 files changed, 6 insertions, 2 deletions

diff --git a/fs/xfs/xfs_trans_extfree.c b/fs/xfs/xfs_trans_extfree.c
index f783d5e9fa70..f7590f5badea 100644
--- a/fs/xfs/xfs_trans_extfree.c
+++ b/fs/xfs/xfs_trans_extfree.c
@@ -69,12 +69,16 @@ xfs_trans_log_efi_extent(xfs_trans_t		*tp,
         tp->t_flags |= XFS_TRANS_DIRTY;
         efip->efi_item.li_desc->lid_flags |= XFS_LID_DIRTY;
 
-        next_extent = efip->efi_next_extent;
+        /*
+         * atomic_inc_return gives us the value after the increment;
+         * we want to use it as an array index so we need to subtract 1 from
+         * it.
+         */
+        next_extent = atomic_inc_return(&efip->efi_next_extent) - 1;
         ASSERT(next_extent < efip->efi_format.efi_nextents);
         extp = &(efip->efi_format.efi_extents[next_extent]);
         extp->ext_start = start_block;
         extp->ext_len = ext_len;
-        efip->efi_next_extent++;
 }