btrfs: cleanup, use enum values for btrfs_path reada
authorDavid Sterba <dsterba@suse.com>
Fri, 27 Nov 2015 15:31:35 +0000 (16:31 +0100)
committerDavid Sterba <dsterba@suse.com>
Thu, 7 Jan 2016 14:01:15 +0000 (15:01 +0100)
Replace the integers by enums for better readability. The value 2 does
not have any meaning since a717531942f488209dded30f6bc648167bcefa72
"Btrfs: do less aggressive btree readahead" (2009-01-22).

Signed-off-by: David Sterba <dsterba@suse.com>
fs/btrfs/ctree.c
fs/btrfs/ctree.h
fs/btrfs/extent-tree.c
fs/btrfs/file-item.c
fs/btrfs/inode-map.c
fs/btrfs/inode.c
fs/btrfs/ioctl.c
fs/btrfs/relocation.c
fs/btrfs/scrub.c
fs/btrfs/volumes.c
fs/btrfs/xattr.c

index 5b8e235c4b6d6299183ebba91976f0d53612c16c..be1be0422ff450e630e82c53b61beae301f0a2d5 100644 (file)
@@ -2248,7 +2248,6 @@ static void reada_for_search(struct btrfs_root *root,
        u64 target;
        u64 nread = 0;
        u64 gen;
-       int direction = path->reada;
        struct extent_buffer *eb;
        u32 nr;
        u32 blocksize;
@@ -2276,16 +2275,16 @@ static void reada_for_search(struct btrfs_root *root,
        nr = slot;
 
        while (1) {
-               if (direction < 0) {
+               if (path->reada == READA_BACK) {
                        if (nr == 0)
                                break;
                        nr--;
-               } else if (direction > 0) {
+               } else if (path->reada == READA_FORWARD) {
                        nr++;
                        if (nr >= nritems)
                                break;
                }
-               if (path->reada < 0 && objectid) {
+               if (path->reada == READA_BACK && objectid) {
                        btrfs_node_key(node, &disk_key, nr);
                        if (btrfs_disk_key_objectid(&disk_key) != objectid)
                                break;
@@ -2493,7 +2492,7 @@ read_block_for_search(struct btrfs_trans_handle *trans,
        btrfs_set_path_blocking(p);
 
        free_extent_buffer(tmp);
-       if (p->reada)
+       if (p->reada != READA_NONE)
                reada_for_search(root, p, level, slot, key->objectid);
 
        btrfs_release_path(p);
index 99059fcb563e743ebe7ed1ee6e8c251fc167fe65..a1cf4c8135789f5f07fbcced7405febeef78b197 100644 (file)
@@ -590,6 +590,7 @@ struct btrfs_node {
  * The slots array records the index of the item or block pointer
  * used while walking the tree.
  */
+enum { READA_NONE = 0, READA_BACK, READA_FORWARD };
 struct btrfs_path {
        struct extent_buffer *nodes[BTRFS_MAX_LEVEL];
        int slots[BTRFS_MAX_LEVEL];
index d796b53850d0a9fa379372373dcd401191550531..9e3639b21567d5a04a93861e50711b05557a3223 100644 (file)
@@ -438,7 +438,7 @@ static noinline void caching_thread(struct btrfs_work *work)
         */
        path->skip_locking = 1;
        path->search_commit_root = 1;
-       path->reada = 1;
+       path->reada = READA_FORWARD;
 
        key.objectid = last;
        key.offset = 0;
@@ -2115,7 +2115,7 @@ static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
        if (!path)
                return -ENOMEM;
 
-       path->reada = 1;
+       path->reada = READA_FORWARD;
        path->leave_spinning = 1;
        /* this will setup the path even if it fails to insert the back ref */
        ret = insert_inline_extent_backref(trans, fs_info->extent_root, path,
@@ -2141,7 +2141,7 @@ static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
        btrfs_mark_buffer_dirty(leaf);
        btrfs_release_path(path);
 
-       path->reada = 1;
+       path->reada = READA_FORWARD;
        path->leave_spinning = 1;
        /* now insert the actual backref */
        ret = insert_extent_backref(trans, root->fs_info->extent_root,
@@ -2254,7 +2254,7 @@ static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
        }
 
 again:
-       path->reada = 1;
+       path->reada = READA_FORWARD;
        path->leave_spinning = 1;
        ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
                                path, 0, 1);
@@ -6438,7 +6438,7 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
        if (!path)
                return -ENOMEM;
 
-       path->reada = 1;
+       path->reada = READA_FORWARD;
        path->leave_spinning = 1;
 
        is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
@@ -9688,7 +9688,7 @@ int btrfs_read_block_groups(struct btrfs_root *root)
        path = btrfs_alloc_path();
        if (!path)
                return -ENOMEM;
-       path->reada = 1;
+       path->reada = READA_FORWARD;
 
        cache_gen = btrfs_super_cache_generation(root->fs_info->super_copy);
        if (btrfs_test_opt(root, SPACE_CACHE) &&
index 58ece6558430094969d7dcea7e477f6949c2eac6..a67e1c828d0f735c3974e9ff0dca098cd759e9d3 100644 (file)
@@ -202,7 +202,7 @@ static int __btrfs_lookup_bio_sums(struct btrfs_root *root,
        }
 
        if (bio->bi_iter.bi_size > PAGE_CACHE_SIZE * 8)
-               path->reada = 2;
+               path->reada = READA_FORWARD;
 
        WARN_ON(bio->bi_vcnt <= 0);
 
@@ -328,7 +328,7 @@ int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
 
        if (search_commit) {
                path->skip_locking = 1;
-               path->reada = 2;
+               path->reada = READA_FORWARD;
                path->search_commit_root = 1;
        }
 
index 53014e963617e7e979a96b3329da4041ba721574..1951ad69382fbe7d488d0ceb4be18e6b839d3a7d 100644 (file)
@@ -48,7 +48,7 @@ static int caching_kthread(void *data)
        /* Since the commit root is read-only, we can safely skip locking. */
        path->skip_locking = 1;
        path->search_commit_root = 1;
-       path->reada = 2;
+       path->reada = READA_FORWARD;
 
        key.objectid = BTRFS_FIRST_FREE_OBJECTID;
        key.offset = 0;
index 3e1398b123aa7926f31cb9ebf755c1fca97d4b09..dc2c1bedbafa0290a2318cf0d5b2cf36191947f7 100644 (file)
@@ -3342,7 +3342,7 @@ int btrfs_orphan_cleanup(struct btrfs_root *root)
                ret = -ENOMEM;
                goto out;
        }
-       path->reada = -1;
+       path->reada = READA_BACK;
 
        key.objectid = BTRFS_ORPHAN_OBJECTID;
        key.type = BTRFS_ORPHAN_ITEM_KEY;
@@ -4308,7 +4308,7 @@ int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
        path = btrfs_alloc_path();
        if (!path)
                return -ENOMEM;
-       path->reada = -1;
+       path->reada = READA_BACK;
 
        /*
         * We want to drop from the next block forward in case this new size is
@@ -5744,7 +5744,7 @@ static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
        if (!path)
                return -ENOMEM;
 
-       path->reada = 1;
+       path->reada = READA_FORWARD;
 
        if (key_type == BTRFS_DIR_INDEX_KEY) {
                INIT_LIST_HEAD(&ins_list);
@@ -6775,7 +6775,7 @@ again:
                 * Chances are we'll be called again, so go ahead and do
                 * readahead
                 */
-               path->reada = 1;
+               path->reada = READA_FORWARD;
        }
 
        ret = btrfs_lookup_file_extent(trans, root, path,
index fd429d7f40abcf600907f7589726e8ca271af1d8..6e896415a73461aeda6db64491df61799116a605 100644 (file)
@@ -3478,7 +3478,7 @@ static int btrfs_clone(struct inode *src, struct inode *inode,
                return ret;
        }
 
-       path->reada = 2;
+       path->reada = READA_FORWARD;
        /* clone data */
        key.objectid = btrfs_ino(src);
        key.type = BTRFS_EXTENT_DATA_KEY;
index b4ca5454ef1a7ebc4fcb8eec476701bc8496a050..ef6d8fc85853851da0da03923b75421982d65d8f 100644 (file)
@@ -708,8 +708,8 @@ struct backref_node *build_backref_tree(struct reloc_control *rc,
                err = -ENOMEM;
                goto out;
        }
-       path1->reada = 1;
-       path2->reada = 2;
+       path1->reada = READA_FORWARD;
+       path2->reada = READA_FORWARD;
 
        node = alloc_backref_node(cache);
        if (!node) {
@@ -2130,7 +2130,7 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
        path = btrfs_alloc_path();
        if (!path)
                return -ENOMEM;
-       path->reada = 1;
+       path->reada = READA_FORWARD;
 
        reloc_root = root->reloc_root;
        root_item = &reloc_root->root_item;
@@ -3527,7 +3527,7 @@ static int find_data_references(struct reloc_control *rc,
        path = btrfs_alloc_path();
        if (!path)
                return -ENOMEM;
-       path->reada = 1;
+       path->reada = READA_FORWARD;
 
        root = read_fs_root(rc->extent_root->fs_info, ref_root);
        if (IS_ERR(root)) {
@@ -3917,7 +3917,7 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
        path = btrfs_alloc_path();
        if (!path)
                return -ENOMEM;
-       path->reada = 1;
+       path->reada = READA_FORWARD;
 
        ret = prepare_to_relocate(rc);
        if (ret) {
@@ -4343,7 +4343,7 @@ int btrfs_recover_relocation(struct btrfs_root *root)
        path = btrfs_alloc_path();
        if (!path)
                return -ENOMEM;
-       path->reada = -1;
+       path->reada = READA_BACK;
 
        key.objectid = BTRFS_TREE_RELOC_OBJECTID;
        key.type = BTRFS_ROOT_ITEM_KEY;
index 1d1f639b7c792d311853b42e3bdd5ad82bc2da53..143f2b7a8edf21d0b728b5ce2e1e66fbaf13e708 100644 (file)
@@ -3507,7 +3507,7 @@ int scrub_enumerate_chunks(struct scrub_ctx *sctx,
        if (!path)
                return -ENOMEM;
 
-       path->reada = 2;
+       path->reada = READA_FORWARD;
        path->search_commit_root = 1;
        path->skip_locking = 1;
 
index 0577d7f4c442d307ad750ef7f52b6d1917dd5a37..e95d24967fa087f43295a203df3ca3ea5c53caa7 100644 (file)
@@ -1102,7 +1102,7 @@ int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
        path = btrfs_alloc_path();
        if (!path)
                return -ENOMEM;
-       path->reada = 2;
+       path->reada = READA_FORWARD;
 
        key.objectid = device->devid;
        key.offset = start;
@@ -1271,7 +1271,7 @@ again:
                goto out;
        }
 
-       path->reada = 2;
+       path->reada = READA_FORWARD;
        path->search_commit_root = 1;
        path->skip_locking = 1;
 
@@ -4260,7 +4260,7 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
        if (!path)
                return -ENOMEM;
 
-       path->reada = 2;
+       path->reada = READA_FORWARD;
 
        lock_chunks(root);
 
index 1fcd7b6e7564defa675b3abe12589473a58e937d..28b4e7e71e614ea3dbce6be15c59c5491a4659b5 100644 (file)
@@ -283,7 +283,7 @@ ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
        path = btrfs_alloc_path();
        if (!path)
                return -ENOMEM;
-       path->reada = 2;
+       path->reada = READA_FORWARD;
 
        /* search for our xattrs */
        ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);