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>
This commit is contained in:
David Sterba 2015-11-10 18:53:56 +01:00
parent 4fb72bf2e9
commit a1ee736268

View file

@ -655,22 +655,20 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir,
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 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir,
&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 @@ fail:
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;
}