Btrfs: cleanup backref search commit root flag stuff

Looking into this backref problem I noticed we're using a macro to what turns
out to essentially be a NULL check to see if we need to search the commit root.
I'm killing this, let's just do what everybody else does and checks if trans ==
NULL.  I've also made it so we pass in the path to __resolve_indirect_refs which
will have the search_commit_root flag set properly already and that way we can
avoid allocating another path when we have a perfectly good one to use.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 290e347b6db3f925f414fd9be4e6ea394da6f887..431ea9211bc1f528a88bab67b6fb55a95f98b431 100644 (file)
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -255,13 +255,11 @@ static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
  * to a logical address
  */
 static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
-                                       int search_commit_root,
-                                       u64 time_seq,
-                                       struct __prelim_ref *ref,
-                                       struct ulist *parents,
-                                       const u64 *extent_item_pos)
+                                 struct btrfs_path *path, u64 time_seq,
+                                 struct __prelim_ref *ref,
+                                 struct ulist *parents,
+                                 const u64 *extent_item_pos)
 {
-       struct btrfs_path *path;
        struct btrfs_root *root;
        struct btrfs_key root_key;
        struct extent_buffer *eb;
@@ -269,11 +267,6 @@ static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
        int root_level;
        int level = ref->level;
 
-       path = btrfs_alloc_path();
-       if (!path)
-               return -ENOMEM;
-       path->search_commit_root = !!search_commit_root;
-
        root_key.objectid = ref->root_id;
        root_key.type = BTRFS_ROOT_ITEM_KEY;
        root_key.offset = (u64)-1;
@@ -314,7 +307,8 @@ static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
                                time_seq, ref->wanted_disk_byte,
                                extent_item_pos);
 out:
-       btrfs_free_path(path);
+       path->lowest_level = 0;
+       btrfs_release_path(path);
        return ret;
 }
 
@@ -322,7 +316,7 @@ out:
  * resolve all indirect backrefs from the list
  */
 static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
-                                  int search_commit_root, u64 time_seq,
+                                  struct btrfs_path *path, u64 time_seq,
                                   struct list_head *head,
                                   const u64 *extent_item_pos)
 {
@@ -349,9 +343,8 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
                        continue;
                if (ref->count == 0)
                        continue;
-               err = __resolve_indirect_ref(fs_info, search_commit_root,
-                                            time_seq, ref, parents,
-                                            extent_item_pos);
+               err = __resolve_indirect_ref(fs_info, path, time_seq, ref,
+                                            parents, extent_item_pos);
                if (err == -ENOMEM)
                        goto out;
                if (err)
@@ -795,7 +788,6 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans,
        struct btrfs_delayed_ref_head *head;
        int info_level = 0;
        int ret;
-       int search_commit_root = (trans == BTRFS_BACKREF_SEARCH_COMMIT_ROOT);
        struct list_head prefs_delayed;
        struct list_head prefs;
        struct __prelim_ref *ref;
@@ -810,7 +802,8 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans,
        path = btrfs_alloc_path();
        if (!path)
                return -ENOMEM;
-       path->search_commit_root = !!search_commit_root;
+       if (!trans)
+               path->search_commit_root = 1;
 
        /*
         * grab both a lock on the path and a lock on the delayed ref head.
@@ -825,7 +818,7 @@ again:
                goto out;
        BUG_ON(ret == 0);
 
-       if (trans != BTRFS_BACKREF_SEARCH_COMMIT_ROOT) {
+       if (trans) {
                /*
                 * look if there are updates for this ref queued and lock the
                 * head
@@ -890,8 +883,8 @@ again:
 
        __merge_refs(&prefs, 1);
 
-       ret = __resolve_indirect_refs(fs_info, search_commit_root, time_seq,
-                                     &prefs, extent_item_pos);
+       ret = __resolve_indirect_refs(fs_info, path, time_seq, &prefs,
+                                     extent_item_pos);
        if (ret)
                goto out;
 
@@ -1459,7 +1452,7 @@ int iterate_extent_inodes(struct btrfs_fs_info *fs_info,
                                iterate_extent_inodes_t *iterate, void *ctx)
 {
        int ret;
-       struct btrfs_trans_handle *trans;
+       struct btrfs_trans_handle *trans = NULL;
        struct ulist *refs = NULL;
        struct ulist *roots = NULL;
        struct ulist_node *ref_node = NULL;
@@ -1471,9 +1464,7 @@ int iterate_extent_inodes(struct btrfs_fs_info *fs_info,
        pr_debug("resolving all inodes for extent %llu\n",
                        extent_item_objectid);
 
-       if (search_commit_root) {
-               trans = BTRFS_BACKREF_SEARCH_COMMIT_ROOT;
-       } else {
+       if (!search_commit_root) {
                trans = btrfs_join_transaction(fs_info->extent_root);
                if (IS_ERR(trans))
                        return PTR_ERR(trans);

diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h
index 0f446d7ca2c0d62b85e560e93574cb44efffc655..8f2e767029322d2d3d0ac2baf996c3964e999cdf 100644 (file)
--- a/fs/btrfs/backref.h
+++ b/fs/btrfs/backref.h
@@ -23,8 +23,6 @@
 #include "ulist.h"
 #include "extent_io.h"
 
-#define BTRFS_BACKREF_SEARCH_COMMIT_ROOT ((struct btrfs_trans_handle *)0)
-
 struct inode_fs_paths {
        struct btrfs_path               *btrfs_path;
        struct btrfs_root               *fs_root;