Btrfs: remove unused write cache pages hook

The btree inode has it's own write cache pages so we can remove this write
cache pages hook as it's not used.  Thanks,

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

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 5d3f813e13a00bdf1a2507b8496c206c74117730..2c18a4eb4d5a1f68bb7a07bddbc99c8a95084e02 100644 (file)
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3347,52 +3347,6 @@ int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
        return btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
 }
 
-int btree_lock_page_hook(struct page *page, void *data,
-                               void (*flush_fn)(void *))
-{
-       struct inode *inode = page->mapping->host;
-       struct btrfs_root *root = BTRFS_I(inode)->root;
-       struct extent_buffer *eb;
-
-       /*
-        * We culled this eb but the page is still hanging out on the mapping,
-        * carry on.
-        */
-       if (!PagePrivate(page))
-               goto out;
-
-       eb = (struct extent_buffer *)page->private;
-       if (!eb) {
-               WARN_ON(1);
-               goto out;
-       }
-       if (page != eb->pages[0])
-               goto out;
-
-       if (!btrfs_try_tree_write_lock(eb)) {
-               flush_fn(data);
-               btrfs_tree_lock(eb);
-       }
-       btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
-
-       if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
-               spin_lock(&root->fs_info->delalloc_lock);
-               if (root->fs_info->dirty_metadata_bytes >= eb->len)
-                       root->fs_info->dirty_metadata_bytes -= eb->len;
-               else
-                       WARN_ON(1);
-               spin_unlock(&root->fs_info->delalloc_lock);
-       }
-
-       btrfs_tree_unlock(eb);
-out:
-       if (!trylock_page(page)) {
-               flush_fn(data);
-               lock_page(page);
-       }
-       return 0;
-}
-
 static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
                              int read_only)
 {
@@ -3787,7 +3741,6 @@ int btrfs_cleanup_transaction(struct btrfs_root *root)
 }
 
 static struct extent_io_ops btree_extent_io_ops = {
-       .write_cache_pages_lock_hook = btree_lock_page_hook,
        .readpage_end_io_hook = btree_readpage_end_io_hook,
        .readpage_io_failed_hook = btree_io_failed_hook,
        .submit_bio_hook = btree_submit_bio_hook,