Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

Pull btrfs updates from Chris Mason:
 "This pull is mostly cleanups and fixes:

   - The raid5/6 cleanups from Zhao Lei fixup some long standing warts
     in the code and add improvements on top of the scrubbing support
     from 3.19.

   - Josef has round one of our ENOSPC fixes coming from large btrfs
     clusters here at FB.

   - Dave Sterba continues a long series of cleanups (thanks Dave), and
     Filipe continues hammering on corner cases in fsync and others

  This all was held up a little trying to track down a use-after-free in
  btrfs raid5/6.  It's not clear yet if this is just made easier to
  trigger with this pull or if its a new bug from the raid5/6 cleanups.
  Dave Sterba is the only one to trigger it so far, but he has a
  consistent way to reproduce, so we'll get it nailed shortly"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (68 commits)
  Btrfs: don't remove extents and xattrs when logging new names
  Btrfs: fix fsync data loss after adding hard link to inode
  Btrfs: fix BUG_ON in btrfs_orphan_add() when delete unused block group
  Btrfs: account for large extents with enospc
  Btrfs: don't set and clear delalloc for O_DIRECT writes
  Btrfs: only adjust outstanding_extents when we do a short write
  btrfs: Fix out-of-space bug
  Btrfs: scrub, fix sleep in atomic context
  Btrfs: fix scheduler warning when syncing log
  Btrfs: Remove unnecessary placeholder in btrfs_err_code
  btrfs: cleanup init for list in free-space-cache
  btrfs: delete chunk allocation attemp when setting block group ro
  btrfs: clear bio reference after submit_one_bio()
  Btrfs: fix scrub race leading to use-after-free
  Btrfs: add missing cleanup on sysfs init failure
  Btrfs: fix race between transaction commit and empty block group removal
  btrfs: add more checks to btrfs_read_sys_array
  btrfs: cleanup, rename a few variables in btrfs_read_sys_array
  btrfs: add checks for sys_chunk_array sizes
  btrfs: more superblock checks, lower bounds on devices and sectorsize/nodesize
  ...

1 files changed, 8 insertions, 17 deletions

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index ca6a3a3b6b6c..5ec03d999c37 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -440,18 +440,9 @@ leave:
  */
 static void btrfs_rm_dev_replace_blocked(struct btrfs_fs_info *fs_info)
 {
-        s64 writers;
-        DEFINE_WAIT(wait);
-
         set_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state);
-        do {
-                prepare_to_wait(&fs_info->replace_wait, &wait,
-                                TASK_UNINTERRUPTIBLE);
-                writers = percpu_counter_sum(&fs_info->bio_counter);
-                if (writers)
-                        schedule();
-                finish_wait(&fs_info->replace_wait, &wait);
-        } while (writers);
+        wait_event(fs_info->replace_wait, !percpu_counter_sum(
+                   &fs_info->bio_counter));
 }
 
 /*
@@ -932,15 +923,15 @@ void btrfs_bio_counter_sub(struct btrfs_fs_info *fs_info, s64 amount)
 
 void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info)
 {
-        DEFINE_WAIT(wait);
-again:
-        percpu_counter_inc(&fs_info->bio_counter);
-        if (test_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state)) {
+        while (1) {
+                percpu_counter_inc(&fs_info->bio_counter);
+                if (likely(!test_bit(BTRFS_FS_STATE_DEV_REPLACING,
+                                     &fs_info->fs_state)))
+                        break;
+
                 btrfs_bio_counter_dec(fs_info);
                 wait_event(fs_info->replace_wait,
                            !test_bit(BTRFS_FS_STATE_DEV_REPLACING,
                                      &fs_info->fs_state));
-                goto again;
         }
-
 }