[3.16.y-ckt stable] Patch "btrfs: cleanup orphans while looking up default subvolume" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    btrfs: cleanup orphans while looking up default subvolume

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt14.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

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>From 3202310e882f4cd7ba36785f1f1a0dbb035c3b34 Mon Sep 17 00:00:00 2001
From: Jeff Mahoney <jeffm at suse.com>
Date: Fri, 20 Mar 2015 14:02:09 -0400
Subject: btrfs: cleanup orphans while looking up default subvolume

commit 727b9784b6085c99c2f836bf4fcc2848dc9cf904 upstream.

Orphans in the fs tree are cleaned up via open_ctree and subvolume
orphans are cleaned via btrfs_lookup_dentry -- except when a default
subvolume is in use.  The name for the default subvolume uses a manual
lookup that doesn't trigger orphan cleanup and needs to trigger it
manually as well. This doesn't apply to the remount case since the
subvolumes are cleaned up by walking the root radix tree.

Signed-off-by: Jeff Mahoney <jeffm at suse.com>
Reviewed-by: David Sterba <dsterba at suse.cz>
Signed-off-by: Chris Mason <clm at fb.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 fs/btrfs/super.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 8e16bca69c56..600035120ca3 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -902,6 +902,15 @@ find_root:
 	if (IS_ERR(new_root))
 		return ERR_CAST(new_root);

+	if (!(sb->s_flags & MS_RDONLY)) {
+		int ret;
+		down_read(&fs_info->cleanup_work_sem);
+		ret = btrfs_orphan_cleanup(new_root);
+		up_read(&fs_info->cleanup_work_sem);
+		if (ret)
+			return ERR_PTR(ret);
+	}
+
 	dir_id = btrfs_root_dirid(&new_root->root_item);
 setup_root:
 	location.objectid = dir_id;