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

Pull btrfs update from Chris Mason:
 "From a feature point of view, most of the code here comes from Miao
  Xie and others at Fujitsu to implement scrubbing and replacing devices
  on raid56.  This has been in development for a while, and it's a big
  improvement.

  Filipe and Josef have a great assortment of fixes, many of which solve
  problems corruptions either after a crash or in error conditions.  I
  still have a round two from Filipe for next week that solves
  corruptions with discard and block group removal"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (62 commits)
  Btrfs: make get_caching_control unconditionally return the ctl
  Btrfs: fix unprotected deletion from pending_chunks list
  Btrfs: fix fs mapping extent map leak
  Btrfs: fix memory leak after block remove + trimming
  Btrfs: make btrfs_abort_transaction consider existence of new block groups
  Btrfs: fix race between writing free space cache and trimming
  Btrfs: fix race between fs trimming and block group remove/allocation
  Btrfs, replace: enable dev-replace for raid56
  Btrfs: fix freeing used extents after removing empty block group
  Btrfs: fix crash caused by block group removal
  Btrfs: fix invalid block group rbtree access after bg is removed
  Btrfs, raid56: fix use-after-free problem in the final device replace procedure on raid56
  Btrfs, replace: write raid56 parity into the replace target device
  Btrfs, replace: write dirty pages into the replace target device
  Btrfs, raid56: support parity scrub on raid56
  Btrfs, raid56: use a variant to record the operation type
  Btrfs, scrub: repair the common data on RAID5/6 if it is corrupted
  Btrfs, raid56: don't change bbio and raid_map
  Btrfs: remove unnecessary code of stripe_index assignment in __btrfs_map_block
  Btrfs: remove noused bbio_ret in __btrfs_map_block in condition
  ...

1 files changed, 4 insertions, 32 deletions

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 080fe66c0349..d49fe8a0f6b5 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -617,7 +617,7 @@ fail:
 	return ret;
 }
 
-static void btrfs_wait_nocow_write(struct btrfs_root *root)
+static void btrfs_wait_for_no_snapshoting_writes(struct btrfs_root *root)
 {
 	s64 writers;
 	DEFINE_WAIT(wait);
@@ -649,7 +649,7 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir,
 
 	atomic_inc(&root->will_be_snapshoted);
 	smp_mb__after_atomic();
-	btrfs_wait_nocow_write(root);
+	btrfs_wait_for_no_snapshoting_writes(root);
 
 	ret = btrfs_start_delalloc_inodes(root, 0);
 	if (ret)
@@ -717,35 +717,6 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir,
 	if (ret)
 		goto fail;
 
-	/*
-	 * If orphan cleanup did remove any orphans, it means the tree was
-	 * modified and therefore the commit root is not the same as the
-	 * current root anymore. This is a problem, because send uses the
-	 * commit root and therefore can see inode items that don't exist
-	 * in the current root anymore, and for example make calls to
-	 * btrfs_iget, which will do tree lookups based on the current root
-	 * and not on the commit root. Those lookups will fail, returning a
-	 * -ESTALE error, and making send fail with that error. So make sure
-	 * a send does not see any orphans we have just removed, and that it
-	 * will see the same inodes regardless of whether a transaction
-	 * commit happened before it started (meaning that the commit root
-	 * will be the same as the current root) or not.
-	 */
-	if (readonly && pending_snapshot->snap->node !=
-	    pending_snapshot->snap->commit_root) {
-		trans = btrfs_join_transaction(pending_snapshot->snap);
-		if (IS_ERR(trans) && PTR_ERR(trans) != -ENOENT) {
-			ret = PTR_ERR(trans);
-			goto fail;
-		}
-		if (!IS_ERR(trans)) {
-			ret = btrfs_commit_transaction(trans,
-						       pending_snapshot->snap);
-			if (ret)
-				goto fail;
-		}
-	}
-
 	inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
 	if (IS_ERR(inode)) {
 		ret = PTR_ERR(inode);
@@ -761,7 +732,8 @@ fail:
 free:
 	kfree(pending_snapshot);
 out:
-	atomic_dec(&root->will_be_snapshoted);
+	if (atomic_dec_and_test(&root->will_be_snapshoted))
+		wake_up_atomic_t(&root->will_be_snapshoted);
 	return ret;
 }