Commit 4cdfd930 authored Jan 24, 2020 by Josef Bacik Committed by David Sterba Mar 23, 2020

btrfs: handle NULL roots in btrfs_put/btrfs_grab_fs_root



We want to use this for dropping all roots, and in some error cases we
may not have a root, so handle this to make the cleanup code easier.
Make btrfs_grab_fs_root the same so we can use it in cases where the
root may not exist (like the quota root).

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

parent a98db0f3

fs/btrfs/disk-io.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -88,6 +88,8 @@ struct btrfs_root btrfs_alloc_dummy_root(struct btrfs_fs_info fs_info);
		*/
		static inline struct btrfs_root btrfs_grab_fs_root(struct btrfs_root root)
		{
		if (!root)
		return NULL;
		if (refcount_inc_not_zero(&root->refs))
		return root;
		return NULL;
		@@ -95,6 +97,8 @@ static inline struct btrfs_root btrfs_grab_fs_root(struct btrfs_root root)

		static inline void btrfs_put_fs_root(struct btrfs_root *root)
		{
		if (!root)
		return;
		if (refcount_dec_and_test(&root->refs))
		kfree(root);
		}