mm: task dirty accounting fix

[safe/jmp/linux-2.6] / fs / btrfs / disk-io.c

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 9c38100..adda739 100644 (file)
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -75,6 +75,40 @@ struct async_submit_bio {
        struct btrfs_work work;
 };
 
+/* These are used to set the lockdep class on the extent buffer locks.
+ * The class is set by the readpage_end_io_hook after the buffer has
+ * passed csum validation but before the pages are unlocked.
+ *
+ * The lockdep class is also set by btrfs_init_new_buffer on freshly
+ * allocated blocks.
+ *
+ * The class is based on the level in the tree block, which allows lockdep
+ * to know that lower nodes nest inside the locks of higher nodes.
+ *
+ * We also add a check to make sure the highest level of the tree is
+ * the same as our lockdep setup here.  If BTRFS_MAX_LEVEL changes, this
+ * code needs update as well.
+ */
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# if BTRFS_MAX_LEVEL != 8
+#  error
+# endif
+static struct lock_class_key btrfs_eb_class[BTRFS_MAX_LEVEL + 1];
+static const char *btrfs_eb_name[BTRFS_MAX_LEVEL + 1] = {
+       /* leaf */
+       "btrfs-extent-00",
+       "btrfs-extent-01",
+       "btrfs-extent-02",
+       "btrfs-extent-03",
+       "btrfs-extent-04",
+       "btrfs-extent-05",
+       "btrfs-extent-06",
+       "btrfs-extent-07",
+       /* highest possible level */
+       "btrfs-extent-08",
+};
+#endif
+
 /*
  * extents on the btree inode are pretty simple, there's one extent
  * that covers the entire device
@@ -347,6 +381,15 @@ static int check_tree_block_fsid(struct btrfs_root *root,
        return ret;
 }
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void btrfs_set_buffer_lockdep_class(struct extent_buffer *eb, int level)
+{
+       lockdep_set_class_and_name(&eb->lock,
+                          &btrfs_eb_class[level],
+                          btrfs_eb_name[level]);
+}
+#endif
+
 static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
                               struct extent_state *state)
 {
@@ -392,6 +435,8 @@ static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
        }
        found_level = btrfs_header_level(eb);
 
+       btrfs_set_buffer_lockdep_class(eb, found_level);
+
        ret = csum_tree_block(root, eb, 1);
        if (ret)
                ret = -EIO;
@@ -799,7 +844,7 @@ struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
        ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
 
        if (ret == 0)
-               buf->flags |= EXTENT_UPTODATE;
+               set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
        else
                WARN_ON(1);
        return buf;
@@ -813,6 +858,10 @@ int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
        if (btrfs_header_generation(buf) ==
            root->fs_info->running_transaction->transid) {
                WARN_ON(!btrfs_tree_locked(buf));
+
+               /* ugh, clear_extent_buffer_dirty can be expensive */
+               btrfs_set_lock_blocking(buf);
+
                clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
                                          buf);
        }
@@ -1503,7 +1552,6 @@ struct btrfs_root *open_ctree(struct super_block *sb,
        INIT_LIST_HEAD(&fs_info->dead_roots);
        INIT_LIST_HEAD(&fs_info->hashers);
        INIT_LIST_HEAD(&fs_info->delalloc_inodes);
-       spin_lock_init(&fs_info->hash_lock);
        spin_lock_init(&fs_info->delalloc_lock);
        spin_lock_init(&fs_info->new_trans_lock);
        spin_lock_init(&fs_info->ref_cache_lock);
@@ -1774,7 +1822,6 @@ struct btrfs_root *open_ctree(struct super_block *sb,
        ret = find_and_setup_root(tree_root, fs_info,
                                  BTRFS_DEV_TREE_OBJECTID, dev_root);
        dev_root->track_dirty = 1;
-
        if (ret)
                goto fail_extent_root;
 
@@ -2312,6 +2359,8 @@ void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
        u64 transid = btrfs_header_generation(buf);
        struct inode *btree_inode = root->fs_info->btree_inode;
 
+       btrfs_set_lock_blocking(buf);
+
        WARN_ON(!btrfs_tree_locked(buf));
        if (transid != root->fs_info->generation) {
                printk(KERN_CRIT "btrfs transid mismatch buffer %llu, "
@@ -2354,14 +2403,13 @@ int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
        int ret;
        ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
        if (ret == 0)
-               buf->flags |= EXTENT_UPTODATE;
+               set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
        return ret;
 }
 
 int btree_lock_page_hook(struct page *page)
 {
        struct inode *inode = page->mapping->host;
-       struct btrfs_root *root = BTRFS_I(inode)->root;
        struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
        struct extent_buffer *eb;
        unsigned long len;
@@ -2376,9 +2424,7 @@ int btree_lock_page_hook(struct page *page)
                goto out;
 
        btrfs_tree_lock(eb);
-       spin_lock(&root->fs_info->hash_lock);
        btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
-       spin_unlock(&root->fs_info->hash_lock);
        btrfs_tree_unlock(eb);
        free_extent_buffer(eb);
 out: