1 files changed, 51 insertions, 5 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index edee7a44f861..574b1245964e 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -205,6 +205,33 @@ static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
         return 0;
 }
 
+static int verify_parent_transid(struct extent_io_tree *io_tree,
+                                 struct extent_buffer *eb, u64 parent_transid)
+{
+        int ret;
+
+        if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
+                return 0;
+
+        lock_extent(io_tree, eb->start, eb->start + eb->len - 1, GFP_NOFS);
+        if (extent_buffer_uptodate(io_tree, eb) &&
+            btrfs_header_generation(eb) == parent_transid) {
+                ret = 0;
+                goto out;
+        }
+        printk("parent transid verify failed on %llu wanted %llu found %llu\n",
+               (unsigned long long)eb->start,
+               (unsigned long long)parent_transid,
+               (unsigned long long)btrfs_header_generation(eb));
+        ret = 1;
+out:
+        clear_extent_buffer_uptodate(io_tree, eb);
+        unlock_extent(io_tree, eb->start, eb->start + eb->len - 1,
+                      GFP_NOFS);
+        return ret;
+
+}
+
 static int btree_read_extent_buffer_pages(struct btrfs_root *root,
                                           struct extent_buffer *eb,
                                           u64 start, u64 parent_transid)
@@ -218,7 +245,8 @@ static int btree_read_extent_buffer_pages(struct btrfs_root *root,
         while (1) {
                 ret = read_extent_buffer_pages(io_tree, eb, start, 1,
                                                btree_get_extent, mirror_num);
-                if (!ret)
+                if (!ret &&
+                    !verify_parent_transid(io_tree, eb, parent_transid))
                         return ret;
 
                 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
@@ -330,6 +358,13 @@ int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
                 ret = -EIO;
                 goto err;
         }
+        if (memcmp_extent_buffer(eb, root->fs_info->fsid,
+                                 (unsigned long)btrfs_header_fsid(eb),
+                                 BTRFS_FSID_SIZE)) {
+                printk("bad fsid on block %Lu\n", eb->start);
+                ret = -EIO;
+                goto err;
+        }
         found_level = btrfs_header_level(eb);
 
         ret = csum_tree_block(root, eb, 1);
@@ -1363,7 +1398,9 @@ static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
                                         "I/O error on %s\n",
                                        bdevname(bh->b_bdev, b));
                 }
-                set_buffer_write_io_error(bh);
+                /* note, we dont' set_buffer_write_io_error because we have
+                 * our own ways of dealing with the IO errors
+                 */
                 clear_buffer_uptodate(bh);
         }
         unlock_buffer(bh);
@@ -1459,7 +1496,8 @@ int write_all_supers(struct btrfs_root *root)
                                 ret = submit_bh(WRITE, bh);
                                 BUG_ON(ret);
                                 wait_on_buffer(bh);
-                                BUG_ON(!buffer_uptodate(bh));
+                                if (!buffer_uptodate(bh))
+                                        total_errors++;
                         } else {
                                 total_errors++;
                         }
@@ -1607,10 +1645,18 @@ int close_ctree(struct btrfs_root *root)
         return 0;
 }
 
-int btrfs_buffer_uptodate(struct extent_buffer *buf)
+int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
 {
+        int ret;
         struct inode *btree_inode = buf->first_page->mapping->host;
-        return extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf);
+
+        ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf);
+        if (!ret)
+                return ret;
+
+        ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
+                                    parent_transid);
+        return !ret;
 }
 
 int btrfs_set_buffer_uptodate(struct extent_buffer *buf)