[PATCH] ext4 balloc: fix off-by-one against grp_goal

grp_goal 0 is a genuine goal (unlike -1), so ext4_try_to_allocate_with_rsv
should treat it as such.

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index af3acf3c37b6f3875d70bfffa7d0d73b8525b84c..2bcca5261eebc13114fde575184248b4c2ccd456 100644 (file)
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -1288,7 +1288,7 @@ ext4_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle,
        }
        /*
         * grp_goal is a group relative block number (if there is a goal)
-        * 0 < grp_goal < EXT4_BLOCKS_PER_GROUP(sb)
+        * 0 <= grp_goal < EXT4_BLOCKS_PER_GROUP(sb)
         * first block is a filesystem wide block number
         * first block is the block number of the first block in this group
         */
@@ -1324,7 +1324,7 @@ ext4_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle,
                        if (!goal_in_my_reservation(&my_rsv->rsv_window,
                                                        grp_goal, group, sb))
                                grp_goal = -1;
-               } else if (grp_goal > 0) {
+               } else if (grp_goal >= 0) {
                        int curr = my_rsv->rsv_end -
                                        (grp_goal + group_first_block) + 1;