ext4: check free block counters in ext4_mb_find_by_goal

Free block counters should be checked before doing allocation.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 3 insertions, 0 deletions

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 2c7c082b8169..bb821a924049 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1660,10 +1660,13 @@ int ext4_mb_find_by_goal(struct ext4_allocation_context *ac,
         int max;
         int err;
         struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb);
+        struct ext4_group_info *grp = ext4_get_group_info(ac->ac_sb, group);
         struct ext4_free_extent ex;
 
         if (!(ac->ac_flags & EXT4_MB_HINT_TRY_GOAL))
                 return 0;
+        if (grp->bb_free == 0)
+                return 0;
 
         err = ext4_mb_load_buddy(ac->ac_sb, group, e4b);
         if (err)