Btrfs: remove btrfs_init_path

btrfs_init_path was initially used when the path objects were on the
stack.  Now all the work is done by btrfs_alloc_path and btrfs_init_path
isn't required.

This patch removes it, and just uses kmem_cache_zalloc to zero out the object.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

fs/btrfs/ctree.c

@@ -38,19 +38,12 @@ static int balance_node_right(struct btrfs_trans_handle *trans,
 static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		   struct btrfs_path *path, int level, int slot);
 
-inline void btrfs_init_path(struct btrfs_path *p)
-{
-	memset(p, 0, sizeof(*p));
-}
-
 struct btrfs_path *btrfs_alloc_path(void)
 {
 	struct btrfs_path *path;
-	path = kmem_cache_alloc(btrfs_path_cachep, GFP_NOFS);
-	if (path) {
-		btrfs_init_path(path);
+	path = kmem_cache_zalloc(btrfs_path_cachep, GFP_NOFS);
+	if (path)
 		path->reada = 1;
-	}
 	return path;
 }
 

fs/btrfs/ctree.h

@@ -1834,7 +1834,6 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
 void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p);
 struct btrfs_path *btrfs_alloc_path(void);
 void btrfs_free_path(struct btrfs_path *p);
-void btrfs_init_path(struct btrfs_path *p);
 void btrfs_set_path_blocking(struct btrfs_path *p);
 void btrfs_clear_path_blocking(struct btrfs_path *p);
 void btrfs_unlock_up_safe(struct btrfs_path *p, int level);

fs/btrfs/inode-map.c

@@ -84,7 +84,6 @@ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
 	search_key.type = 0;
 	search_key.offset = 0;
 
-	btrfs_init_path(path);
 	start_found = 0;
 	ret = btrfs_search_slot(trans, root, &search_key, path, 0, 0);
 	if (ret < 0)

fs/btrfs/inode.c

@@ -2531,8 +2531,6 @@ noinline int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
 	key.offset = (u64)-1;
 	key.type = (u8)-1;
 
-	btrfs_init_path(path);
-
 search_again:
 	ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
 	if (ret < 0)