Commit 7c855e16 authored by Leo Martins's avatar Leo Martins Committed by David Sterba
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btrfs: remove conditional path allocation in btrfs_read_locked_inode() 



Remove conditional path allocation from btrfs_read_locked_inode(). Add
an ASSERT(path) to indicate it should never be called with a NULL path.

Call btrfs_read_locked_inode() directly from btrfs_iget(). This causes
code duplication between btrfs_iget() and btrfs_iget_path(), but I
think this is justifiable as it removes the need for conditionally
allocating the path inside of btrfs_read_locked_inode(). This makes the
code easier to reason about and makes it clear who has the
responsibility of allocating and freeing the path.

Signed-off-by: default avatarLeo Martins <loemra.dev@gmail.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 69673992

fs/btrfs/inode.c

+29 −17
Original line number Diff line number Diff line
@@ -3795,11 +3795,9 @@ static int btrfs_add_inode_to_root(struct btrfs_inode *inode, bool prealloc) 
 *

 * On failure clean up the inode.

 */

static int btrfs_read_locked_inode(struct inode *inode,

				   struct btrfs_path *in_path)

static int btrfs_read_locked_inode(struct inode *inode, struct btrfs_path *path)

{

	struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);

	struct btrfs_path *path = in_path;

	struct extent_buffer *leaf;

	struct btrfs_inode_item *inode_item;

	struct btrfs_root *root = BTRFS_I(inode)->root;
@@ -3819,18 +3817,12 @@ static int btrfs_read_locked_inode(struct inode *inode, 
	if (!ret)

		filled = true;



	if (!path) {

		path = btrfs_alloc_path();

		if (!path)

			goto out;

	}

	ASSERT(path);



	btrfs_get_inode_key(BTRFS_I(inode), &location);



	ret = btrfs_lookup_inode(NULL, root, path, &location, 0);

	if (ret) {

		if (path != in_path)

			btrfs_free_path(path);

		/*

		 * ret > 0 can come from btrfs_search_slot called by

		 * btrfs_lookup_inode(), this means the inode was not found.
@@ -3972,8 +3964,6 @@ static int btrfs_read_locked_inode(struct inode *inode, 
				  btrfs_ino(BTRFS_I(inode)),

				  btrfs_root_id(root), ret);

	}

	if (path != in_path)

		btrfs_free_path(path);



	if (!maybe_acls)

		cache_no_acl(inode);
@@ -5579,10 +5569,8 @@ static struct inode *btrfs_iget_locked(u64 ino, struct btrfs_root *root) 
}



/*

 * Get an inode object given its inode number and corresponding root.

 * Path can be preallocated to prevent recursing back to iget through

 * allocator. NULL is also valid but may require an additional allocation

 * later.

 * Get an inode object given its inode number and corresponding root.  Path is

 * preallocated to prevent recursing back to iget through allocator.

 */

struct inode *btrfs_iget_path(u64 ino, struct btrfs_root *root,

			      struct btrfs_path *path)
@@ -5605,9 +5593,33 @@ struct inode *btrfs_iget_path(u64 ino, struct btrfs_root *root, 
	return inode;

}



/*

 * Get an inode object given its inode number and corresponding root.

 */

struct inode *btrfs_iget(u64 ino, struct btrfs_root *root)

{

	return btrfs_iget_path(ino, root, NULL);

	struct inode *inode;

	struct btrfs_path *path;

	int ret;



	inode = btrfs_iget_locked(ino, root);

	if (!inode)

		return ERR_PTR(-ENOMEM);



	if (!(inode->i_state & I_NEW))

		return inode;



	path = btrfs_alloc_path();

	if (!path)

		return ERR_PTR(-ENOMEM);



	ret = btrfs_read_locked_inode(inode, path);

	btrfs_free_path(path);

	if (ret)

		return ERR_PTR(ret);



	unlock_new_inode(inode);

	return inode;

}



static struct inode *new_simple_dir(struct inode *dir,