ext4: don't hold spinlock while calling ext4_issue_discard()

We can't hold the block group spinlock because we ext4_issue_discard()
calls wait and hence can get rescheduled.

Google-Bug-Id: 3017678

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 53472e27b327..ccdfec6acb75 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -4696,12 +4696,12 @@ do_more:
                  * with group lock held. generate_buddy look at
                  * them with group lock_held
                  */
+                if (test_opt(sb, DISCARD))
+                        ext4_issue_discard(sb, block_group, bit, count);
                 ext4_lock_group(sb, block_group);
                 mb_clear_bits(bitmap_bh->b_data, bit, count);
                 mb_free_blocks(inode, &e4b, bit, count);
                 ext4_mb_return_to_preallocation(inode, &e4b, block, count);
-                if (test_opt(sb, DISCARD))
-                        ext4_issue_discard(sb, block_group, bit, count);
         }
 
         ret = ext4_free_blks_count(sb, gdp) + count;