1 files changed, 14 insertions, 82 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index b531c36455d8..830d261d0e6b 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -359,10 +359,14 @@ static int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
 
         tree = &BTRFS_I(page->mapping->host)->io_tree;
 
-        if (page->private == EXTENT_PAGE_PRIVATE)
+        if (page->private == EXTENT_PAGE_PRIVATE) {
+                WARN_ON(1);
                 goto out;
-        if (!page->private)
+        }
+        if (!page->private) {
+                WARN_ON(1);
                 goto out;
+        }
         len = page->private >> 2;
         WARN_ON(len == 0);
 
@@ -843,7 +847,6 @@ static const struct address_space_operations btree_aops = {
         .writepages     = btree_writepages,
         .releasepage    = btree_releasepage,
         .invalidatepage = btree_invalidatepage,
-        .sync_page      = block_sync_page,
 #ifdef CONFIG_MIGRATION
         .migratepage    = btree_migratepage,
 #endif
@@ -1327,82 +1330,6 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits)
 }
 
 /*
- * this unplugs every device on the box, and it is only used when page
- * is null
- */
-static void __unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
-{
-        struct btrfs_device *device;
-        struct btrfs_fs_info *info;
-
-        info = (struct btrfs_fs_info *)bdi->unplug_io_data;
-        list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
-                if (!device->bdev)
-                        continue;
-
-                bdi = blk_get_backing_dev_info(device->bdev);
-                if (bdi->unplug_io_fn)
-                        bdi->unplug_io_fn(bdi, page);
-        }
-}
-
-static void btrfs_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
-{
-        struct inode *inode;
-        struct extent_map_tree *em_tree;
-        struct extent_map *em;
-        struct address_space *mapping;
-        u64 offset;
-
-        /* the generic O_DIRECT read code does this */
-        if (1 || !page) {
-                __unplug_io_fn(bdi, page);
-                return;
-        }
-
-        /*
-         * page->mapping may change at any time.  Get a consistent copy
-         * and use that for everything below
-         */
-        smp_mb();
-        mapping = page->mapping;
-        if (!mapping)
-                return;
-
-        inode = mapping->host;
-
-        /*
-         * don't do the expensive searching for a small number of
-         * devices
-         */
-        if (BTRFS_I(inode)->root->fs_info->fs_devices->open_devices <= 2) {
-                __unplug_io_fn(bdi, page);
-                return;
-        }
-
-        offset = page_offset(page);
-
-        em_tree = &BTRFS_I(inode)->extent_tree;
-        read_lock(&em_tree->lock);
-        em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
-        read_unlock(&em_tree->lock);
-        if (!em) {
-                __unplug_io_fn(bdi, page);
-                return;
-        }
-
-        if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
-                free_extent_map(em);
-                __unplug_io_fn(bdi, page);
-                return;
-        }
-        offset = offset - em->start;
-        btrfs_unplug_page(&BTRFS_I(inode)->root->fs_info->mapping_tree,
-                          em->block_start + offset, page);
-        free_extent_map(em);
-}
-
-/*
  * If this fails, caller must call bdi_destroy() to get rid of the
  * bdi again.
  */
@@ -1416,8 +1343,6 @@ static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
                 return err;
 
         bdi->ra_pages   = default_backing_dev_info.ra_pages;
-        bdi->unplug_io_fn       = btrfs_unplug_io_fn;
-        bdi->unplug_io_data     = info;
         bdi->congested_fn       = btrfs_congested_fn;
         bdi->congested_data     = info;
         return 0;
@@ -1550,6 +1475,7 @@ static int transaction_kthread(void *arg)
                 spin_unlock(&root->fs_info->new_trans_lock);
 
                 trans = btrfs_join_transaction(root, 1);
+                BUG_ON(IS_ERR(trans));
                 if (transid == trans->transid) {
                         ret = btrfs_commit_transaction(trans, root);
                         BUG_ON(ret);
@@ -2453,10 +2379,14 @@ int btrfs_commit_super(struct btrfs_root *root)
         up_write(&root->fs_info->cleanup_work_sem);
 
         trans = btrfs_join_transaction(root, 1);
+        if (IS_ERR(trans))
+                return PTR_ERR(trans);
         ret = btrfs_commit_transaction(trans, root);
         BUG_ON(ret);
         /* run commit again to drop the original snapshot */
         trans = btrfs_join_transaction(root, 1);
+        if (IS_ERR(trans))
+                return PTR_ERR(trans);
         btrfs_commit_transaction(trans, root);
         ret = btrfs_write_and_wait_transaction(NULL, root);
         BUG_ON(ret);
@@ -2484,7 +2414,7 @@ int close_ctree(struct btrfs_root *root)
          * ERROR state on disk.
          *
          * 2. when btrfs flips readonly just in btrfs_commit_super,
-         * and in such case, btrfs cannnot write sb via btrfs_commit_super,
+         * and in such case, btrfs cannot write sb via btrfs_commit_super,
          * and since fs_state has been set BTRFS_SUPER_FLAG_ERROR flag,
          * btrfs will cleanup all FS resources first and write sb then.
          */
@@ -2554,6 +2484,8 @@ int close_ctree(struct btrfs_root *root)
         kfree(fs_info->chunk_root);
         kfree(fs_info->dev_root);
         kfree(fs_info->csum_root);
+        kfree(fs_info);
+
         return 0;
 }