[PATCH] Btrfs: allocate ulists in btrfs_check_shared() using GFP_KERNEL

[fdmanana@kernel.org]

From: Filipe Manana <fdmanana@suse.com>

As of commit bb739cf08e8f32 ("btrfs: btrfs_check_shared should manage its
own transaction") btrfs_check_shared() manages its own transaction, it
no longer receives a transaction handle as parameter. Since it is used
only in the fiemap path, the ulists it needs to use are allocated before
it grabs a transaction handle and we are not holding any locks that could
cause a deadlock in case reclaim happens during a memory allocation, we
can use the GFP_KERNEL flag to allocate the ulists instead of GFP_NOFS.
So do that switch.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/backref.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 876e6bb93797..377978bb8845 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -1481,8 +1481,8 @@ int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr)
 		.share_count = 0,
 	};
 
-	tmp = ulist_alloc(GFP_NOFS);
-	roots = ulist_alloc(GFP_NOFS);
+	tmp = ulist_alloc(GFP_KERNEL);
+	roots = ulist_alloc(GFP_KERNEL);
 	if (!tmp || !roots) {
 		ulist_free(tmp);
 		ulist_free(roots);
-- 
2.11.0