btrfs: do an allocation earlier during snapshot creation
We can allocate pending_snapshot earlier and do not have to do cleanup
in case of failure.
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 6e89641..fa25091 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -655,22 +655,20 @@
if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
return -EINVAL;
+ pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
+ if (!pending_snapshot)
+ return -ENOMEM;
+
atomic_inc(&root->will_be_snapshoted);
smp_mb__after_atomic();
btrfs_wait_for_no_snapshoting_writes(root);
ret = btrfs_start_delalloc_inodes(root, 0);
if (ret)
- goto out;
+ goto dec_and_free;
btrfs_wait_ordered_extents(root, -1);
- pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
- if (!pending_snapshot) {
- ret = -ENOMEM;
- goto out;
- }
-
btrfs_init_block_rsv(&pending_snapshot->block_rsv,
BTRFS_BLOCK_RSV_TEMP);
/*
@@ -686,7 +684,7 @@
&pending_snapshot->qgroup_reserved,
false);
if (ret)
- goto free;
+ goto dec_and_free;
pending_snapshot->dentry = dentry;
pending_snapshot->root = root;
@@ -737,11 +735,11 @@
btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
&pending_snapshot->block_rsv,
pending_snapshot->qgroup_reserved);
-free:
- kfree(pending_snapshot);
-out:
+dec_and_free:
if (atomic_dec_and_test(&root->will_be_snapshoted))
wake_up_atomic_t(&root->will_be_snapshoted);
+ kfree(pending_snapshot);
+
return ret;
}