btrfs: preallocate path for snapshot creation at ioctl time

We can also preallocate btrfs_path that's used during pending snapshot
creation and avoid another late ENOMEM failure.

Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 4 insertions, 5 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 2074106122d9..be463b7f1f30 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -1319,11 +1319,8 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
         u64 root_flags;
         uuid_le new_uuid;
 
-        path = btrfs_alloc_path();
-        if (!path) {
-                pending->error = -ENOMEM;
-                return 0;
-        }
+        ASSERT(pending->path);
+        path = pending->path;
 
         ASSERT(pending->root_item);
         new_root_item = pending->root_item;
@@ -1561,6 +1558,8 @@ no_free_objectid:
         kfree(new_root_item);
         pending->root_item = NULL;
         btrfs_free_path(path);
+        pending->path = NULL;
+
         return ret;
 }