1 files changed, 368 insertions, 293 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index d24a841a8722..09ef25f0c6c7 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -48,20 +48,19 @@
 static struct extent_io_ops btree_extent_io_ops;
 static void end_workqueue_fn(struct btrfs_work *work);
 static void free_fs_root(struct btrfs_root *root);
-static void btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
+static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
                                     int read_only);
-static int btrfs_destroy_ordered_operations(struct btrfs_root *root);
-static int btrfs_destroy_ordered_extents(struct btrfs_root *root);
+static void btrfs_destroy_ordered_operations(struct btrfs_root *root);
+static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
 static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
                                       struct btrfs_root *root);
-static int btrfs_destroy_pending_snapshots(struct btrfs_transaction *t);
-static int btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
+static void btrfs_destroy_pending_snapshots(struct btrfs_transaction *t);
+static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
 static int btrfs_destroy_marked_extents(struct btrfs_root *root,
                                         struct extent_io_tree *dirty_pages,
                                         int mark);
 static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
                                        struct extent_io_tree *pinned_extents);
-static int btrfs_cleanup_transaction(struct btrfs_root *root);
 
 /*
  * end_io_wq structs are used to do processing in task context when an IO is
@@ -99,6 +98,7 @@ struct async_submit_bio {
          */
         u64 bio_offset;
         struct btrfs_work work;
+        int error;
 };
 
 /*
@@ -332,8 +332,8 @@ static int verify_parent_transid(struct extent_io_tree *io_tree,
                 return 0;
 
         lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
-                         0, &cached_state, GFP_NOFS);
-        if (extent_buffer_uptodate(io_tree, eb, cached_state) &&
+                         0, &cached_state);
+        if (extent_buffer_uptodate(eb) &&
             btrfs_header_generation(eb) == parent_transid) {
                 ret = 0;
                 goto out;
@@ -344,7 +344,7 @@ static int verify_parent_transid(struct extent_io_tree *io_tree,
                        (unsigned long long)parent_transid,
                        (unsigned long long)btrfs_header_generation(eb));
         ret = 1;
-        clear_extent_buffer_uptodate(io_tree, eb, &cached_state);
+        clear_extent_buffer_uptodate(eb);
 out:
         unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
                              &cached_state, GFP_NOFS);
@@ -360,9 +360,11 @@ static int btree_read_extent_buffer_pages(struct btrfs_root *root,
                                           u64 start, u64 parent_transid)
 {
         struct extent_io_tree *io_tree;
+        int failed = 0;
         int ret;
         int num_copies = 0;
         int mirror_num = 0;
+        int failed_mirror = 0;
 
         clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
         io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
@@ -370,9 +372,8 @@ static int btree_read_extent_buffer_pages(struct btrfs_root *root,
                 ret = read_extent_buffer_pages(io_tree, eb, start,
                                                WAIT_COMPLETE,
                                                btree_get_extent, mirror_num);
-                if (!ret &&
-                    !verify_parent_transid(io_tree, eb, parent_transid))
-                        return ret;
+                if (!ret && !verify_parent_transid(io_tree, eb, parent_transid))
+                        break;
 
                 /*
                  * This buffer's crc is fine, but its contents are corrupted, so
@@ -380,18 +381,31 @@ static int btree_read_extent_buffer_pages(struct btrfs_root *root,
                  * any less wrong.
                  */
                 if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags))
-                        return ret;
+                        break;
+
+                if (!failed_mirror) {
+                        failed = 1;
+                        printk(KERN_ERR "failed mirror was %d\n", eb->failed_mirror);
+                        failed_mirror = eb->failed_mirror;
+                }
 
                 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
                                               eb->start, eb->len);
                 if (num_copies == 1)
-                        return ret;
+                        break;
 
                 mirror_num++;
+                if (mirror_num == failed_mirror)
+                        mirror_num++;
+
                 if (mirror_num > num_copies)
-                        return ret;
+                        break;
         }
-        return -EIO;
+
+        if (failed && !ret)
+                repair_eb_io_failure(root, eb, failed_mirror);
+
+        return ret;
 }
 
 /*
@@ -404,50 +418,27 @@ static int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
         struct extent_io_tree *tree;
         u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
         u64 found_start;
-        unsigned long len;
         struct extent_buffer *eb;
-        int ret;
 
         tree = &BTRFS_I(page->mapping->host)->io_tree;
 
-        if (page->private == EXTENT_PAGE_PRIVATE) {
-                WARN_ON(1);
-                goto out;
-        }
-        if (!page->private) {
-                WARN_ON(1);
-                goto out;
-        }
-        len = page->private >> 2;
-        WARN_ON(len == 0);
-
-        eb = alloc_extent_buffer(tree, start, len, page);
-        if (eb == NULL) {
-                WARN_ON(1);
-                goto out;
-        }
-        ret = btree_read_extent_buffer_pages(root, eb, start + PAGE_CACHE_SIZE,
-                                             btrfs_header_generation(eb));
-        BUG_ON(ret);
-        WARN_ON(!btrfs_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN));
-
+        eb = (struct extent_buffer *)page->private;
+        if (page != eb->pages[0])
+                return 0;
         found_start = btrfs_header_bytenr(eb);
         if (found_start != start) {
                 WARN_ON(1);
-                goto err;
+                return 0;
         }
-        if (eb->first_page != page) {
+        if (eb->pages[0] != page) {
                 WARN_ON(1);
-                goto err;
+                return 0;
         }
         if (!PageUptodate(page)) {
                 WARN_ON(1);
-                goto err;
+                return 0;
         }
         csum_tree_block(root, eb, 0);
-err:
-        free_extent_buffer(eb);
-out:
         return 0;
 }
 
@@ -537,34 +528,74 @@ static noinline int check_leaf(struct btrfs_root *root,
         return 0;
 }
 
+struct extent_buffer *find_eb_for_page(struct extent_io_tree *tree,
+                                       struct page *page, int max_walk)
+{
+        struct extent_buffer *eb;
+        u64 start = page_offset(page);
+        u64 target = start;
+        u64 min_start;
+
+        if (start < max_walk)
+                min_start = 0;
+        else
+                min_start = start - max_walk;
+
+        while (start >= min_start) {
+                eb = find_extent_buffer(tree, start, 0);
+                if (eb) {
+                        /*
+                         * we found an extent buffer and it contains our page
+                         * horray!
+                         */
+                        if (eb->start <= target &&
+                            eb->start + eb->len > target)
+                                return eb;
+
+                        /* we found an extent buffer that wasn't for us */
+                        free_extent_buffer(eb);
+                        return NULL;
+                }
+                if (start == 0)
+                        break;
+                start -= PAGE_CACHE_SIZE;
+        }
+        return NULL;
+}
+
 static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
                                struct extent_state *state)
 {
         struct extent_io_tree *tree;
         u64 found_start;
         int found_level;
-        unsigned long len;
         struct extent_buffer *eb;
         struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
         int ret = 0;
+        int reads_done;
 
-        tree = &BTRFS_I(page->mapping->host)->io_tree;
-        if (page->private == EXTENT_PAGE_PRIVATE)
-                goto out;
         if (!page->private)
                 goto out;
 
-        len = page->private >> 2;
-        WARN_ON(len == 0);
+        tree = &BTRFS_I(page->mapping->host)->io_tree;
+        eb = (struct extent_buffer *)page->private;
+
+        /* the pending IO might have been the only thing that kept this buffer
+         * in memory.  Make sure we have a ref for all this other checks
+         */
+        extent_buffer_get(eb);
+
+        reads_done = atomic_dec_and_test(&eb->io_pages);
+        if (!reads_done)
+                goto err;
 
-        eb = alloc_extent_buffer(tree, start, len, page);
-        if (eb == NULL) {
+        if (test_bit(EXTENT_BUFFER_IOERR, &eb->bflags)) {
                 ret = -EIO;
-                goto out;
+                goto err;
         }
 
         found_start = btrfs_header_bytenr(eb);
-        if (found_start != start) {
+        if (found_start != eb->start) {
                 printk_ratelimited(KERN_INFO "btrfs bad tree block start "
                                "%llu %llu\n",
                                (unsigned long long)found_start,
@@ -572,13 +603,6 @@ static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
                 ret = -EIO;
                 goto err;
         }
-        if (eb->first_page != page) {
-                printk(KERN_INFO "btrfs bad first page %lu %lu\n",
-                       eb->first_page->index, page->index);
-                WARN_ON(1);
-                ret = -EIO;
-                goto err;
-        }
         if (check_tree_block_fsid(root, eb)) {
                 printk_ratelimited(KERN_INFO "btrfs bad fsid on block %llu\n",
                                (unsigned long long)eb->start);
@@ -606,48 +630,31 @@ static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
                 ret = -EIO;
         }
 
-        end = min_t(u64, eb->len, PAGE_CACHE_SIZE);
-        end = eb->start + end - 1;
+        if (!ret)
+                set_extent_buffer_uptodate(eb);
 err:
         if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
                 clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
                 btree_readahead_hook(root, eb, eb->start, ret);
         }
 
+        if (ret)
+                clear_extent_buffer_uptodate(eb);
         free_extent_buffer(eb);
 out:
         return ret;
 }
 
-static int btree_io_failed_hook(struct bio *failed_bio,
-                         struct page *page, u64 start, u64 end,
-                         int mirror_num, struct extent_state *state)
+static int btree_io_failed_hook(struct page *page, int failed_mirror)
 {
-        struct extent_io_tree *tree;
-        unsigned long len;
         struct extent_buffer *eb;
         struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 
-        tree = &BTRFS_I(page->mapping->host)->io_tree;
-        if (page->private == EXTENT_PAGE_PRIVATE)
-                goto out;
-        if (!page->private)
-                goto out;
-
-        len = page->private >> 2;
-        WARN_ON(len == 0);
-
-        eb = alloc_extent_buffer(tree, start, len, page);
-        if (eb == NULL)
-                goto out;
-
-        if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
-                clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
+        eb = (struct extent_buffer *)page->private;
+        set_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
+        eb->failed_mirror = failed_mirror;
+        if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
                 btree_readahead_hook(root, eb, eb->start, -EIO);
-        }
-        free_extent_buffer(eb);
-
-out:
         return -EIO;    /* we fixed nothing */
 }
 
@@ -719,11 +726,14 @@ unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
 static void run_one_async_start(struct btrfs_work *work)
 {
         struct async_submit_bio *async;
+        int ret;
 
         async = container_of(work, struct  async_submit_bio, work);
-        async->submit_bio_start(async->inode, async->rw, async->bio,
-                               async->mirror_num, async->bio_flags,
-                               async->bio_offset);
+        ret = async->submit_bio_start(async->inode, async->rw, async->bio,
+                                      async->mirror_num, async->bio_flags,
+                                      async->bio_offset);
+        if (ret)
+                async->error = ret;
 }
 
 static void run_one_async_done(struct btrfs_work *work)
@@ -744,6 +754,12 @@ static void run_one_async_done(struct btrfs_work *work)
             waitqueue_active(&fs_info->async_submit_wait))
                 wake_up(&fs_info->async_submit_wait);
 
+        /* If an error occured we just want to clean up the bio and move on */
+        if (async->error) {
+                bio_endio(async->bio, async->error);
+                return;
+        }
+
         async->submit_bio_done(async->inode, async->rw, async->bio,
                                async->mirror_num, async->bio_flags,
                                async->bio_offset);
@@ -785,6 +801,8 @@ int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
         async->bio_flags = bio_flags;
         async->bio_offset = bio_offset;
 
+        async->error = 0;
+
         atomic_inc(&fs_info->nr_async_submits);
 
         if (rw & REQ_SYNC)
@@ -806,15 +824,18 @@ static int btree_csum_one_bio(struct bio *bio)
         struct bio_vec *bvec = bio->bi_io_vec;
         int bio_index = 0;
         struct btrfs_root *root;
+        int ret = 0;
 
         WARN_ON(bio->bi_vcnt <= 0);
         while (bio_index < bio->bi_vcnt) {
                 root = BTRFS_I(bvec->bv_page->mapping->host)->root;
-                csum_dirty_buffer(root, bvec->bv_page);
+                ret = csum_dirty_buffer(root, bvec->bv_page);
+                if (ret)
+                        break;
                 bio_index++;
                 bvec++;
         }
-        return 0;
+        return ret;
 }
 
 static int __btree_submit_bio_start(struct inode *inode, int rw,
@@ -826,8 +847,7 @@ static int __btree_submit_bio_start(struct inode *inode, int rw,
          * when we're called for a write, we're already in the async
          * submission context.  Just jump into btrfs_map_bio
          */
-        btree_csum_one_bio(bio);
-        return 0;
+        return btree_csum_one_bio(bio);
 }
 
 static int __btree_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
@@ -847,15 +867,16 @@ static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
 {
         int ret;
 
-        ret = btrfs_bio_wq_end_io(BTRFS_I(inode)->root->fs_info,
-                                          bio, 1);
-        BUG_ON(ret);
-
         if (!(rw & REQ_WRITE)) {
+
                 /*
                  * called for a read, do the setup so that checksum validation
                  * can happen in the async kernel threads
                  */
+                ret = btrfs_bio_wq_end_io(BTRFS_I(inode)->root->fs_info,
+                                          bio, 1);
+                if (ret)
+                        return ret;
                 return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
                                      mirror_num, 0);
         }
@@ -893,34 +914,6 @@ static int btree_migratepage(struct address_space *mapping,
 }
 #endif
 
-static int btree_writepage(struct page *page, struct writeback_control *wbc)
-{
-        struct extent_io_tree *tree;
-        struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
-        struct extent_buffer *eb;
-        int was_dirty;
-
-        tree = &BTRFS_I(page->mapping->host)->io_tree;
-        if (!(current->flags & PF_MEMALLOC)) {
-                return extent_write_full_page(tree, page,
-                                              btree_get_extent, wbc);
-        }
-
-        redirty_page_for_writepage(wbc, page);
-        eb = btrfs_find_tree_block(root, page_offset(page), PAGE_CACHE_SIZE);
-        WARN_ON(!eb);
-
-        was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags);
-        if (!was_dirty) {
-                spin_lock(&root->fs_info->delalloc_lock);
-                root->fs_info->dirty_metadata_bytes += PAGE_CACHE_SIZE;
-                spin_unlock(&root->fs_info->delalloc_lock);
-        }
-        free_extent_buffer(eb);
-
-        unlock_page(page);
-        return 0;
-}
 
 static int btree_writepages(struct address_space *mapping,
                             struct writeback_control *wbc)
@@ -940,7 +933,7 @@ static int btree_writepages(struct address_space *mapping,
                 if (num_dirty < thresh)
                         return 0;
         }
-        return extent_writepages(tree, mapping, btree_get_extent, wbc);
+        return btree_write_cache_pages(mapping, wbc);
 }
 
 static int btree_readpage(struct file *file, struct page *page)
@@ -952,16 +945,8 @@ static int btree_readpage(struct file *file, struct page *page)
 
 static int btree_releasepage(struct page *page, gfp_t gfp_flags)
 {
-        struct extent_io_tree *tree;
-        struct extent_map_tree *map;
-        int ret;
-
         if (PageWriteback(page) || PageDirty(page))
                 return 0;
-
-        tree = &BTRFS_I(page->mapping->host)->io_tree;
-        map = &BTRFS_I(page->mapping->host)->extent_tree;
-
         /*
          * We need to mask out eg. __GFP_HIGHMEM and __GFP_DMA32 as we're doing
          * slab allocation from alloc_extent_state down the callchain where
@@ -969,18 +954,7 @@ static int btree_releasepage(struct page *page, gfp_t gfp_flags)
          */
         gfp_flags &= ~GFP_SLAB_BUG_MASK;
 
-        ret = try_release_extent_state(map, tree, page, gfp_flags);
-        if (!ret)
-                return 0;
-
-        ret = try_release_extent_buffer(tree, page);
-        if (ret == 1) {
-                ClearPagePrivate(page);
-                set_page_private(page, 0);
-                page_cache_release(page);
-        }
-
-        return ret;
+        return try_release_extent_buffer(page, gfp_flags);
 }
 
 static void btree_invalidatepage(struct page *page, unsigned long offset)
@@ -998,15 +972,28 @@ static void btree_invalidatepage(struct page *page, unsigned long offset)
         }
 }
 
+static int btree_set_page_dirty(struct page *page)
+{
+        struct extent_buffer *eb;
+
+        BUG_ON(!PagePrivate(page));
+        eb = (struct extent_buffer *)page->private;
+        BUG_ON(!eb);
+        BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
+        BUG_ON(!atomic_read(&eb->refs));
+        btrfs_assert_tree_locked(eb);
+        return __set_page_dirty_nobuffers(page);
+}
+
 static const struct address_space_operations btree_aops = {
         .readpage       = btree_readpage,
-        .writepage      = btree_writepage,
         .writepages     = btree_writepages,
         .releasepage    = btree_releasepage,
         .invalidatepage = btree_invalidatepage,
 #ifdef CONFIG_MIGRATION
         .migratepage    = btree_migratepage,
 #endif
+        .set_page_dirty = btree_set_page_dirty,
 };
 
 int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
@@ -1049,7 +1036,7 @@ int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, u32 blocksize,
         if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
                 free_extent_buffer(buf);
                 return -EIO;
-        } else if (extent_buffer_uptodate(io_tree, buf, NULL)) {
+        } else if (extent_buffer_uptodate(buf)) {
                 *eb = buf;
         } else {
                 free_extent_buffer(buf);
@@ -1074,20 +1061,20 @@ struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
         struct extent_buffer *eb;
 
         eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
-                                 bytenr, blocksize, NULL);
+                                 bytenr, blocksize);
         return eb;
 }
 
 
 int btrfs_write_tree_block(struct extent_buffer *buf)
 {
-        return filemap_fdatawrite_range(buf->first_page->mapping, buf->start,
+        return filemap_fdatawrite_range(buf->pages[0]->mapping, buf->start,
                                         buf->start + buf->len - 1);
 }
 
 int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
 {
-        return filemap_fdatawait_range(buf->first_page->mapping,
+        return filemap_fdatawait_range(buf->pages[0]->mapping,
                                        buf->start, buf->start + buf->len - 1);
 }
 
@@ -1102,17 +1089,13 @@ struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
                 return NULL;
 
         ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
-
-        if (ret == 0)
-                set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
         return buf;
 
 }
 
-int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
-                     struct extent_buffer *buf)
+void clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
+                      struct extent_buffer *buf)
 {
-        struct inode *btree_inode = root->fs_info->btree_inode;
         if (btrfs_header_generation(buf) ==
             root->fs_info->running_transaction->transid) {
                 btrfs_assert_tree_locked(buf);
@@ -1121,23 +1104,27 @@ int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
                         spin_lock(&root->fs_info->delalloc_lock);
                         if (root->fs_info->dirty_metadata_bytes >= buf->len)
                                 root->fs_info->dirty_metadata_bytes -= buf->len;
-                        else
-                                WARN_ON(1);
+                        else {
+                                spin_unlock(&root->fs_info->delalloc_lock);
+                                btrfs_panic(root->fs_info, -EOVERFLOW,
+                                          "Can't clear %lu bytes from "
+                                          " dirty_mdatadata_bytes (%lu)",
+                                          buf->len,
+                                          root->fs_info->dirty_metadata_bytes);
+                        }
                         spin_unlock(&root->fs_info->delalloc_lock);
                 }
 
                 /* ugh, clear_extent_buffer_dirty needs to lock the page */
                 btrfs_set_lock_blocking(buf);
-                clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
-                                          buf);
+                clear_extent_buffer_dirty(buf);
         }
-        return 0;
 }
 
-static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
-                        u32 stripesize, struct btrfs_root *root,
-                        struct btrfs_fs_info *fs_info,
-                        u64 objectid)
+static void __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
+                         u32 stripesize, struct btrfs_root *root,
+                         struct btrfs_fs_info *fs_info,
+                         u64 objectid)
 {
         root->node = NULL;
         root->commit_root = NULL;
@@ -1189,13 +1176,12 @@ static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
         root->defrag_running = 0;
         root->root_key.objectid = objectid;
         root->anon_dev = 0;
-        return 0;
 }
 
-static int find_and_setup_root(struct btrfs_root *tree_root,
-                               struct btrfs_fs_info *fs_info,
-                               u64 objectid,
-                               struct btrfs_root *root)
+static int __must_check find_and_setup_root(struct btrfs_root *tree_root,
+                                            struct btrfs_fs_info *fs_info,
+                                            u64 objectid,
+                                            struct btrfs_root *root)
 {
         int ret;
         u32 blocksize;
@@ -1208,7 +1194,8 @@ static int find_and_setup_root(struct btrfs_root *tree_root,
                                    &root->root_item, &root->root_key);
         if (ret > 0)
                 return -ENOENT;
-        BUG_ON(ret);
+        else if (ret < 0)
+                return ret;
 
         generation = btrfs_root_generation(&root->root_item);
         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
@@ -1377,7 +1364,7 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
                                      blocksize, generation);
         root->commit_root = btrfs_root_node(root);
-        BUG_ON(!root->node);
+        BUG_ON(!root->node); /* -ENOMEM */
 out:
         if (location->objectid != BTRFS_TREE_LOG_OBJECTID) {
                 root->ref_cows = 1;
@@ -1513,41 +1500,6 @@ static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
         return 0;
 }
 
-static int bio_ready_for_csum(struct bio *bio)
-{
-        u64 length = 0;
-        u64 buf_len = 0;
-        u64 start = 0;
-        struct page *page;
-        struct extent_io_tree *io_tree = NULL;
-        struct bio_vec *bvec;
-        int i;
-        int ret;
-
-        bio_for_each_segment(bvec, bio, i) {
-                page = bvec->bv_page;
-                if (page->private == EXTENT_PAGE_PRIVATE) {
-                        length += bvec->bv_len;
-                        continue;
-                }
-                if (!page->private) {
-                        length += bvec->bv_len;
-                        continue;
-                }
-                length = bvec->bv_len;
-                buf_len = page->private >> 2;
-                start = page_offset(page) + bvec->bv_offset;
-                io_tree = &BTRFS_I(page->mapping->host)->io_tree;
-        }
-        /* are we fully contained in this bio? */
-        if (buf_len <= length)
-                return 1;
-
-        ret = extent_range_uptodate(io_tree, start + length,
-                                    start + buf_len - 1);
-        return ret;
-}
-
 /*
  * called by the kthread helper functions to finally call the bio end_io
  * functions.  This is where read checksum verification actually happens
@@ -1563,17 +1515,6 @@ static void end_workqueue_fn(struct btrfs_work *work)
         bio = end_io_wq->bio;
         fs_info = end_io_wq->info;
 
-        /* metadata bio reads are special because the whole tree block must
-         * be checksummed at once.  This makes sure the entire block is in
-         * ram and up to date before trying to verify things.  For
-         * blocksize <= pagesize, it is basically a noop
-         */
-        if (!(bio->bi_rw & REQ_WRITE) && end_io_wq->metadata &&
-            !bio_ready_for_csum(bio)) {
-                btrfs_queue_worker(&fs_info->endio_meta_workers,
-                                   &end_io_wq->work);
-                return;
-        }
         error = end_io_wq->error;
         bio->bi_private = end_io_wq->private;
         bio->bi_end_io = end_io_wq->end_io;
@@ -1614,9 +1555,10 @@ static int transaction_kthread(void *arg)
         u64 transid;
         unsigned long now;
         unsigned long delay;
-        int ret;
+        bool cannot_commit;
 
         do {
+                cannot_commit = false;
                 delay = HZ * 30;
                 vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
                 mutex_lock(&root->fs_info->transaction_kthread_mutex);
@@ -1638,11 +1580,14 @@ static int transaction_kthread(void *arg)
                 transid = cur->transid;
                 spin_unlock(&root->fs_info->trans_lock);
 
+                /* If the file system is aborted, this will always fail. */
                 trans = btrfs_join_transaction(root);
-                BUG_ON(IS_ERR(trans));
+                if (IS_ERR(trans)) {
+                        cannot_commit = true;
+                        goto sleep;
+                }
                 if (transid == trans->transid) {
-                        ret = btrfs_commit_transaction(trans, root);
-                        BUG_ON(ret);
+                        btrfs_commit_transaction(trans, root);
                 } else {
                         btrfs_end_transaction(trans, root);
                 }
@@ -1653,7 +1598,8 @@ sleep:
                 if (!try_to_freeze()) {
                         set_current_state(TASK_INTERRUPTIBLE);
                         if (!kthread_should_stop() &&
-                            !btrfs_transaction_blocked(root->fs_info))
+                            (!btrfs_transaction_blocked(root->fs_info) ||
+                             cannot_commit))
                                 schedule_timeout(delay);
                         __set_current_state(TASK_RUNNING);
                 }
@@ -2042,6 +1988,7 @@ int open_ctree(struct super_block *sb,
         RB_CLEAR_NODE(&BTRFS_I(fs_info->btree_inode)->rb_node);
         extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
                              fs_info->btree_inode->i_mapping);
+        BTRFS_I(fs_info->btree_inode)->io_tree.track_uptodate = 0;
         extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree);
 
         BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
@@ -2084,6 +2031,7 @@ int open_ctree(struct super_block *sb,
         __setup_root(4096, 4096, 4096, 4096, tree_root,
                      fs_info, BTRFS_ROOT_TREE_OBJECTID);
 
+        invalidate_bdev(fs_devices->latest_bdev);
         bh = btrfs_read_dev_super(fs_devices->latest_bdev);
         if (!bh) {
                 err = -EINVAL;
@@ -2104,7 +2052,12 @@ int open_ctree(struct super_block *sb,
         /* check FS state, whether FS is broken. */
         fs_info->fs_state |= btrfs_super_flags(disk_super);
 
-        btrfs_check_super_valid(fs_info, sb->s_flags & MS_RDONLY);
+        ret = btrfs_check_super_valid(fs_info, sb->s_flags & MS_RDONLY);
+        if (ret) {
+                printk(KERN_ERR "btrfs: superblock contains fatal errors\n");
+                err = ret;
+                goto fail_alloc;
+        }
 
         /*
          * run through our array of backup supers and setup
@@ -2135,10 +2088,55 @@ int open_ctree(struct super_block *sb,
                 goto fail_alloc;
         }
 
+        if (btrfs_super_leafsize(disk_super) !=
+            btrfs_super_nodesize(disk_super)) {
+                printk(KERN_ERR "BTRFS: couldn't mount because metadata "
+                       "blocksizes don't match.  node %d leaf %d\n",
+                       btrfs_super_nodesize(disk_super),
+                       btrfs_super_leafsize(disk_super));
+                err = -EINVAL;
+                goto fail_alloc;
+        }
+        if (btrfs_super_leafsize(disk_super) > BTRFS_MAX_METADATA_BLOCKSIZE) {
+                printk(KERN_ERR "BTRFS: couldn't mount because metadata "
+                       "blocksize (%d) was too large\n",
+                       btrfs_super_leafsize(disk_super));
+                err = -EINVAL;
+                goto fail_alloc;
+        }
+
         features = btrfs_super_incompat_flags(disk_super);
         features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
         if (tree_root->fs_info->compress_type & BTRFS_COMPRESS_LZO)
                 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
+
+        /*
+         * flag our filesystem as having big metadata blocks if
+         * they are bigger than the page size
+         */
+        if (btrfs_super_leafsize(disk_super) > PAGE_CACHE_SIZE) {
+                if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
+                        printk(KERN_INFO "btrfs flagging fs with big metadata feature\n");
+                features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
+        }
+
+        nodesize = btrfs_super_nodesize(disk_super);
+        leafsize = btrfs_super_leafsize(disk_super);
+        sectorsize = btrfs_super_sectorsize(disk_super);
+        stripesize = btrfs_super_stripesize(disk_super);
+
+        /*
+         * mixed block groups end up with duplicate but slightly offset
+         * extent buffers for the same range.  It leads to corruptions
+         */
+        if ((features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
+            (sectorsize != leafsize)) {
+                printk(KERN_WARNING "btrfs: unequal leaf/node/sector sizes "
+                                "are not allowed for mixed block groups on %s\n",
+                                sb->s_id);
+                goto fail_alloc;
+        }
+
         btrfs_set_super_incompat_flags(disk_super, features);
 
         features = btrfs_super_compat_ro_flags(disk_super) &
@@ -2242,10 +2240,6 @@ int open_ctree(struct super_block *sb,
         fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
                                     4 * 1024 * 1024 / PAGE_CACHE_SIZE);
 
-        nodesize = btrfs_super_nodesize(disk_super);
-        leafsize = btrfs_super_leafsize(disk_super);
-        sectorsize = btrfs_super_sectorsize(disk_super);
-        stripesize = btrfs_super_stripesize(disk_super);
         tree_root->nodesize = nodesize;
         tree_root->leafsize = leafsize;
         tree_root->sectorsize = sectorsize;
@@ -2260,6 +2254,12 @@ int open_ctree(struct super_block *sb,
                 goto fail_sb_buffer;
         }
 
+        if (sectorsize < PAGE_SIZE) {
+                printk(KERN_WARNING "btrfs: Incompatible sector size "
+                       "found on %s\n", sb->s_id);
+                goto fail_sb_buffer;
+        }
+
         mutex_lock(&fs_info->chunk_mutex);
         ret = btrfs_read_sys_array(tree_root);
         mutex_unlock(&fs_info->chunk_mutex);
@@ -2279,7 +2279,7 @@ int open_ctree(struct super_block *sb,
         chunk_root->node = read_tree_block(chunk_root,
                                            btrfs_super_chunk_root(disk_super),
                                            blocksize, generation);
-        BUG_ON(!chunk_root->node);
+        BUG_ON(!chunk_root->node); /* -ENOMEM */
         if (!test_bit(EXTENT_BUFFER_UPTODATE, &chunk_root->node->bflags)) {
                 printk(KERN_WARNING "btrfs: failed to read chunk root on %s\n",
                        sb->s_id);
@@ -2301,6 +2301,12 @@ int open_ctree(struct super_block *sb,
 
         btrfs_close_extra_devices(fs_devices);
 
+        if (!fs_devices->latest_bdev) {
+                printk(KERN_CRIT "btrfs: failed to read devices on %s\n",
+                       sb->s_id);
+                goto fail_tree_roots;
+        }
+
 retry_root_backup:
         blocksize = btrfs_level_size(tree_root,
                                      btrfs_super_root_level(disk_super));
@@ -2413,21 +2419,31 @@ retry_root_backup:
                 log_tree_root->node = read_tree_block(tree_root, bytenr,
                                                       blocksize,
                                                       generation + 1);
+                /* returns with log_tree_root freed on success */
                 ret = btrfs_recover_log_trees(log_tree_root);
-                BUG_ON(ret);
+                if (ret) {
+                        btrfs_error(tree_root->fs_info, ret,
+                                    "Failed to recover log tree");
+                        free_extent_buffer(log_tree_root->node);
+                        kfree(log_tree_root);
+                        goto fail_trans_kthread;
+                }
 
                 if (sb->s_flags & MS_RDONLY) {
-                        ret =  btrfs_commit_super(tree_root);
-                        BUG_ON(ret);
+                        ret = btrfs_commit_super(tree_root);
+                        if (ret)
+                                goto fail_trans_kthread;
                 }
         }
 
         ret = btrfs_find_orphan_roots(tree_root);
-        BUG_ON(ret);
+        if (ret)
+                goto fail_trans_kthread;
 
         if (!(sb->s_flags & MS_RDONLY)) {
                 ret = btrfs_cleanup_fs_roots(fs_info);
-                BUG_ON(ret);
+                if (ret) {
+                        }
 
                 ret = btrfs_recover_relocation(tree_root);
                 if (ret < 0) {
@@ -2847,6 +2863,8 @@ int write_all_supers(struct btrfs_root *root, int max_mirrors)
         if (total_errors > max_errors) {
                 printk(KERN_ERR "btrfs: %d errors while writing supers\n",
                        total_errors);
+
+                /* This shouldn't happen. FUA is masked off if unsupported */
                 BUG();
         }
 
@@ -2863,9 +2881,9 @@ int write_all_supers(struct btrfs_root *root, int max_mirrors)
         }
         mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
         if (total_errors > max_errors) {
-                printk(KERN_ERR "btrfs: %d errors while writing supers\n",
-                       total_errors);
-                BUG();
+                btrfs_error(root->fs_info, -EIO,
+                            "%d errors while writing supers", total_errors);
+                return -EIO;
         }
         return 0;
 }
@@ -2879,7 +2897,20 @@ int write_ctree_super(struct btrfs_trans_handle *trans,
         return ret;
 }
 
-int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
+/* Kill all outstanding I/O */
+void btrfs_abort_devices(struct btrfs_root *root)
+{
+        struct list_head *head;
+        struct btrfs_device *dev;
+        mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
+        head = &root->fs_info->fs_devices->devices;
+        list_for_each_entry_rcu(dev, head, dev_list) {
+                blk_abort_queue(dev->bdev->bd_disk->queue);
+        }
+        mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
+}
+
+void btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
 {
         spin_lock(&fs_info->fs_roots_radix_lock);
         radix_tree_delete(&fs_info->fs_roots_radix,
@@ -2892,7 +2923,6 @@ int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
         __btrfs_remove_free_space_cache(root->free_ino_pinned);
         __btrfs_remove_free_space_cache(root->free_ino_ctl);
         free_fs_root(root);
-        return 0;
 }
 
 static void free_fs_root(struct btrfs_root *root)
@@ -2909,7 +2939,7 @@ static void free_fs_root(struct btrfs_root *root)
         kfree(root);
 }
 
-static int del_fs_roots(struct btrfs_fs_info *fs_info)
+static void del_fs_roots(struct btrfs_fs_info *fs_info)
 {
         int ret;
         struct btrfs_root *gang[8];
@@ -2938,7 +2968,6 @@ static int del_fs_roots(struct btrfs_fs_info *fs_info)
                 for (i = 0; i < ret; i++)
                         btrfs_free_fs_root(fs_info, gang[i]);
         }
-        return 0;
 }
 
 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
@@ -2987,14 +3016,21 @@ int btrfs_commit_super(struct btrfs_root *root)
         if (IS_ERR(trans))
                 return PTR_ERR(trans);
         ret = btrfs_commit_transaction(trans, root);
-        BUG_ON(ret);
+        if (ret)
+                return ret;
         /* run commit again to drop the original snapshot */
         trans = btrfs_join_transaction(root);
         if (IS_ERR(trans))
                 return PTR_ERR(trans);
-        btrfs_commit_transaction(trans, root);
+        ret = btrfs_commit_transaction(trans, root);
+        if (ret)
+                return ret;
         ret = btrfs_write_and_wait_transaction(NULL, root);
-        BUG_ON(ret);
+        if (ret) {
+                btrfs_error(root->fs_info, ret,
+                            "Failed to sync btree inode to disk.");
+                return ret;
+        }
 
         ret = write_ctree_super(NULL, root, 0);
         return ret;
@@ -3110,10 +3146,9 @@ int close_ctree(struct btrfs_root *root)
 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
 {
         int ret;
-        struct inode *btree_inode = buf->first_page->mapping->host;
+        struct inode *btree_inode = buf->pages[0]->mapping->host;
 
-        ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf,
-                                     NULL);
+        ret = extent_buffer_uptodate(buf);
         if (!ret)
                 return ret;
 
@@ -3124,16 +3159,13 @@ int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
 
 int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
 {
-        struct inode *btree_inode = buf->first_page->mapping->host;
-        return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree,
-                                          buf);
+        return set_extent_buffer_uptodate(buf);
 }
 
 void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
 {
-        struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
+        struct btrfs_root *root = BTRFS_I(buf->pages[0]->mapping->host)->root;
         u64 transid = btrfs_header_generation(buf);
-        struct inode *btree_inode = root->fs_info->btree_inode;
         int was_dirty;
 
         btrfs_assert_tree_locked(buf);
@@ -3145,8 +3177,7 @@ void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
                         (unsigned long long)root->fs_info->generation);
                 WARN_ON(1);
         }
-        was_dirty = set_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
-                                            buf);
+        was_dirty = set_extent_buffer_dirty(buf);
         if (!was_dirty) {
                 spin_lock(&root->fs_info->delalloc_lock);
                 root->fs_info->dirty_metadata_bytes += buf->len;
@@ -3200,12 +3231,8 @@ void __btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
 
 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
 {
-        struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
-        int ret;
-        ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
-        if (ret == 0)
-                set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
-        return ret;
+        struct btrfs_root *root = BTRFS_I(buf->pages[0]->mapping->host)->root;
+        return btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
 }
 
 static int btree_lock_page_hook(struct page *page, void *data,
@@ -3213,17 +3240,21 @@ static int btree_lock_page_hook(struct page *page, void *data,
 {
         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;
-        u64 bytenr = page_offset(page);
 
-        if (page->private == EXTENT_PAGE_PRIVATE)
+        /*
+         * We culled this eb but the page is still hanging out on the mapping,
+         * carry on.
+         */
+        if (!PagePrivate(page))
                 goto out;
 
-        len = page->private >> 2;
-        eb = find_extent_buffer(io_tree, bytenr, len);
-        if (!eb)
+        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)) {
@@ -3242,7 +3273,6 @@ static int btree_lock_page_hook(struct page *page, void *data,
         }
 
         btrfs_tree_unlock(eb);
-        free_extent_buffer(eb);
 out:
         if (!trylock_page(page)) {
                 flush_fn(data);
@@ -3251,15 +3281,23 @@ out:
         return 0;
 }
 
-static void btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
+static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
                               int read_only)
 {
+        if (btrfs_super_csum_type(fs_info->super_copy) >= ARRAY_SIZE(btrfs_csum_sizes)) {
+                printk(KERN_ERR "btrfs: unsupported checksum algorithm\n");
+                return -EINVAL;
+        }
+
         if (read_only)
-                return;
+                return 0;
 
-        if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
+        if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
                 printk(KERN_WARNING "warning: mount fs with errors, "
                        "running btrfsck is recommended\n");
+        }
+
+        return 0;
 }
 
 int btrfs_error_commit_super(struct btrfs_root *root)
@@ -3281,7 +3319,7 @@ int btrfs_error_commit_super(struct btrfs_root *root)
         return ret;
 }
 
-static int btrfs_destroy_ordered_operations(struct btrfs_root *root)
+static void btrfs_destroy_ordered_operations(struct btrfs_root *root)
 {
         struct btrfs_inode *btrfs_inode;
         struct list_head splice;
@@ -3303,11 +3341,9 @@ static int btrfs_destroy_ordered_operations(struct btrfs_root *root)
 
         spin_unlock(&root->fs_info->ordered_extent_lock);
         mutex_unlock(&root->fs_info->ordered_operations_mutex);
-
-        return 0;
 }
 
-static int btrfs_destroy_ordered_extents(struct btrfs_root *root)
+static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
 {
         struct list_head splice;
         struct btrfs_ordered_extent *ordered;
@@ -3339,12 +3375,10 @@ static int btrfs_destroy_ordered_extents(struct btrfs_root *root)
         }
 
         spin_unlock(&root->fs_info->ordered_extent_lock);
-
-        return 0;
 }
 
-static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
-                                      struct btrfs_root *root)
+int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
+                               struct btrfs_root *root)
 {
         struct rb_node *node;
         struct btrfs_delayed_ref_root *delayed_refs;
@@ -3353,6 +3387,7 @@ static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
 
         delayed_refs = &trans->delayed_refs;
 
+again:
         spin_lock(&delayed_refs->lock);
         if (delayed_refs->num_entries == 0) {
                 spin_unlock(&delayed_refs->lock);
@@ -3374,6 +3409,7 @@ static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
                         struct btrfs_delayed_ref_head *head;
 
                         head = btrfs_delayed_node_to_head(ref);
+                        spin_unlock(&delayed_refs->lock);
                         mutex_lock(&head->mutex);
                         kfree(head->extent_op);
                         delayed_refs->num_heads--;
@@ -3381,8 +3417,9 @@ static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
                                 delayed_refs->num_heads_ready--;
                         list_del_init(&head->cluster);
                         mutex_unlock(&head->mutex);
+                        btrfs_put_delayed_ref(ref);
+                        goto again;
                 }
-
                 spin_unlock(&delayed_refs->lock);
                 btrfs_put_delayed_ref(ref);
 
@@ -3395,7 +3432,7 @@ static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
         return ret;
 }
 
-static int btrfs_destroy_pending_snapshots(struct btrfs_transaction *t)
+static void btrfs_destroy_pending_snapshots(struct btrfs_transaction *t)
 {
         struct btrfs_pending_snapshot *snapshot;
         struct list_head splice;
@@ -3413,11 +3450,9 @@ static int btrfs_destroy_pending_snapshots(struct btrfs_transaction *t)
 
                 kfree(snapshot);
         }
-
-        return 0;
 }
 
-static int btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
+static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
 {
         struct btrfs_inode *btrfs_inode;
         struct list_head splice;
@@ -3437,8 +3472,6 @@ static int btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
         }
 
         spin_unlock(&root->fs_info->delalloc_lock);
-
-        return 0;
 }
 
 static int btrfs_destroy_marked_extents(struct btrfs_root *root,
@@ -3529,13 +3562,43 @@ static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
         return 0;
 }
 
-static int btrfs_cleanup_transaction(struct btrfs_root *root)
+void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
+                                   struct btrfs_root *root)
+{
+        btrfs_destroy_delayed_refs(cur_trans, root);
+        btrfs_block_rsv_release(root, &root->fs_info->trans_block_rsv,
+                                cur_trans->dirty_pages.dirty_bytes);
+
+        /* FIXME: cleanup wait for commit */
+        cur_trans->in_commit = 1;
+        cur_trans->blocked = 1;
+        if (waitqueue_active(&root->fs_info->transaction_blocked_wait))
+                wake_up(&root->fs_info->transaction_blocked_wait);
+
+        cur_trans->blocked = 0;
+        if (waitqueue_active(&root->fs_info->transaction_wait))
+                wake_up(&root->fs_info->transaction_wait);
+
+        cur_trans->commit_done = 1;
+        if (waitqueue_active(&cur_trans->commit_wait))
+                wake_up(&cur_trans->commit_wait);
+
+        btrfs_destroy_pending_snapshots(cur_trans);
+
+        btrfs_destroy_marked_extents(root, &cur_trans->dirty_pages,
+                                     EXTENT_DIRTY);
+
+        /*
+        memset(cur_trans, 0, sizeof(*cur_trans));
+        kmem_cache_free(btrfs_transaction_cachep, cur_trans);
+        */
+}
+
+int btrfs_cleanup_transaction(struct btrfs_root *root)
 {
         struct btrfs_transaction *t;
         LIST_HEAD(list);
 
-        WARN_ON(1);
-
         mutex_lock(&root->fs_info->transaction_kthread_mutex);
 
         spin_lock(&root->fs_info->trans_lock);
@@ -3600,6 +3663,17 @@ static int btrfs_cleanup_transaction(struct btrfs_root *root)
         return 0;
 }
 
+static int btree_writepage_io_failed_hook(struct bio *bio, struct page *page,
+                                          u64 start, u64 end,
+                                          struct extent_state *state)
+{
+        struct super_block *sb = page->mapping->host->i_sb;
+        struct btrfs_fs_info *fs_info = btrfs_sb(sb);
+        btrfs_error(fs_info, -EIO,
+                    "Error occured while writing out btree at %llu", start);
+        return -EIO;
+}
+
 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,
@@ -3607,4 +3681,5 @@ static struct extent_io_ops btree_extent_io_ops = {
         .submit_bio_hook = btree_submit_bio_hook,
         /* note we're sharing with inode.c for the merge bio hook */
         .merge_bio_hook = btrfs_merge_bio_hook,
+        .writepage_io_failed_hook = btree_writepage_io_failed_hook,
 };