Btrfs: dynamic allocation of path struct

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 28 insertions, 19 deletions

diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c
index f37dab87de1..ddc1c13a535 100644
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -6,7 +6,7 @@
 int btrfs_find_last_root(struct btrfs_root *root, u64 objectid,
 			struct btrfs_root_item *item, struct btrfs_key *key)
 {
-	struct btrfs_path path;
+	struct btrfs_path *path;
 	struct btrfs_key search_key;
 	struct btrfs_leaf *l;
 	int ret;
@@ -16,14 +16,16 @@ int btrfs_find_last_root(struct btrfs_root *root, u64 objectid,
 	search_key.flags = (u32)-1;
 	search_key.offset = (u32)-1;
 
-	btrfs_init_path(&path);
-	ret = btrfs_search_slot(NULL, root, &search_key, &path, 0, 0);
+	path = btrfs_alloc_path();
+	BUG_ON(!path);
+	btrfs_init_path(path);
+	ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
 	if (ret < 0)
 		goto out;
 	BUG_ON(ret == 0);
-	l = btrfs_buffer_leaf(path.nodes[0]);
-	BUG_ON(path.slots[0] == 0);
-	slot = path.slots[0] - 1;
+	l = btrfs_buffer_leaf(path->nodes[0]);
+	BUG_ON(path->slots[0] == 0);
+	slot = path->slots[0] - 1;
 	if (btrfs_disk_key_objectid(&l->items[slot].key) != objectid) {
 		ret = 1;
 		goto out;
@@ -31,9 +33,10 @@ int btrfs_find_last_root(struct btrfs_root *root, u64 objectid,
 	memcpy(item, btrfs_item_ptr(l, slot, struct btrfs_root_item),
 		sizeof(*item));
 	btrfs_disk_key_to_cpu(key, &l->items[slot].key);
-	btrfs_release_path(root, &path);
 	ret = 0;
 out:
+	btrfs_release_path(root, path);
+	btrfs_free_path(path);
 	return ret;
 }
 
@@ -41,24 +44,27 @@ int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root
 		      *root, struct btrfs_key *key, struct btrfs_root_item
 		      *item)
 {
-	struct btrfs_path path;
+	struct btrfs_path *path;
 	struct btrfs_leaf *l;
 	int ret;
 	int slot;
 	struct btrfs_root_item *update_item;
 
-	btrfs_init_path(&path);
-	ret = btrfs_search_slot(trans, root, key, &path, 0, 1);
+	path = btrfs_alloc_path();
+	BUG_ON(!path);
+	btrfs_init_path(path);
+	ret = btrfs_search_slot(trans, root, key, path, 0, 1);
 	if (ret < 0)
 		goto out;
 	BUG_ON(ret != 0);
-	l = btrfs_buffer_leaf(path.nodes[0]);
-	slot = path.slots[0];
+	l = btrfs_buffer_leaf(path->nodes[0]);
+	slot = path->slots[0];
 	update_item = btrfs_item_ptr(l, slot, struct btrfs_root_item);
 	btrfs_memcpy(root, l, update_item, item, sizeof(*item));
-	btrfs_mark_buffer_dirty(path.nodes[0]);
+	btrfs_mark_buffer_dirty(path->nodes[0]);
 out:
-	btrfs_release_path(root, &path);
+	btrfs_release_path(root, path);
+	btrfs_free_path(path);
 	return ret;
 }
 
@@ -75,16 +81,19 @@ int btrfs_insert_root(struct btrfs_trans_handle *trans, struct btrfs_root
 int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		   struct btrfs_key *key)
 {
-	struct btrfs_path path;
+	struct btrfs_path *path;
 	int ret;
 
-	btrfs_init_path(&path);
-	ret = btrfs_search_slot(trans, root, key, &path, -1, 1);
+	path = btrfs_alloc_path();
+	BUG_ON(!path);
+	btrfs_init_path(path);
+	ret = btrfs_search_slot(trans, root, key, path, -1, 1);
 	if (ret < 0)
 		goto out;
 	BUG_ON(ret != 0);
-	ret = btrfs_del_item(trans, root, &path);
+	ret = btrfs_del_item(trans, root, path);
 out:
-	btrfs_release_path(root, &path);
+	btrfs_release_path(root, path);
+	btrfs_free_path(path);
 	return ret;
 }