Btrfs: handle errors in btrfs_orphan_cleanup

If we cannot truncate an inode for some reason we will never delete the orphan
item associated with that inode, which means that we will loop forever in
btrfs_orphan_cleanup.  Instead of doing this just return error so we fail to
mount.  It sucks, but hey it's better than hanging.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>

6 files changed, 50 insertions, 23 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 34142d5647df..841330f3d68d 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2529,7 +2529,7 @@ int btrfs_update_inode(struct btrfs_trans_handle *trans,
                               struct inode *inode);
 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode);
 int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode);
-void btrfs_orphan_cleanup(struct btrfs_root *root);
+int btrfs_orphan_cleanup(struct btrfs_root *root);
 void btrfs_orphan_pre_snapshot(struct btrfs_trans_handle *trans,
                                 struct btrfs_pending_snapshot *pending,
                                 u64 *bytes_to_reserve);
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index e1aa8d607bc7..495b1ac45f8c 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2058,9 +2058,14 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 
         if (!(sb->s_flags & MS_RDONLY)) {
                 down_read(&fs_info->cleanup_work_sem);
-                btrfs_orphan_cleanup(fs_info->fs_root);
-                btrfs_orphan_cleanup(fs_info->tree_root);
+                err = btrfs_orphan_cleanup(fs_info->fs_root);
+                if (!err)
+                        err = btrfs_orphan_cleanup(fs_info->tree_root);
                 up_read(&fs_info->cleanup_work_sem);
+                if (err) {
+                        close_ctree(tree_root);
+                        return ERR_PTR(err);
+                }
         }
 
         return tree_root;
@@ -2435,8 +2440,12 @@ int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
 
                 root_objectid = gang[ret - 1]->root_key.objectid + 1;
                 for (i = 0; i < ret; i++) {
+                        int err;
+
                         root_objectid = gang[i]->root_key.objectid;
-                        btrfs_orphan_cleanup(gang[i]);
+                        err = btrfs_orphan_cleanup(gang[i]);
+                        if (err)
+                                return err;
                 }
                 root_objectid++;
         }
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 27376c97d85f..a8f4e8d2ba60 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -7619,7 +7619,8 @@ int btrfs_cleanup_reloc_trees(struct btrfs_root *root)
 
         reloc_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
         BUG_ON(!reloc_root);
-        btrfs_orphan_cleanup(reloc_root);
+        ret = btrfs_orphan_cleanup(reloc_root);
+        BUG_ON(ret);
         return 0;
 }
 
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index d83025063ee7..0600265cb9b0 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2284,7 +2284,7 @@ int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode)
  * this cleans up any orphans that may be left on the list from the last use
  * of this root.
  */
-void btrfs_orphan_cleanup(struct btrfs_root *root)
+int btrfs_orphan_cleanup(struct btrfs_root *root)
 {
         struct btrfs_path *path;
         struct extent_buffer *leaf;
@@ -2294,10 +2294,13 @@ void btrfs_orphan_cleanup(struct btrfs_root *root)
         int ret = 0, nr_unlink = 0, nr_truncate = 0;
 
         if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
-                return;
+                return 0;
 
         path = btrfs_alloc_path();
-        BUG_ON(!path);
+        if (!path) {
+                ret = -ENOMEM;
+                goto out;
+        }
         path->reada = -1;
 
         key.objectid = BTRFS_ORPHAN_OBJECTID;
@@ -2306,11 +2309,8 @@ void btrfs_orphan_cleanup(struct btrfs_root *root)
 
         while (1) {
                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
-                if (ret < 0) {
-                        printk(KERN_ERR "Error searching slot for orphan: %d"
-                               "\n", ret);
-                        break;
-                }
+                if (ret < 0)
+                        goto out;
 
                 /*
                  * if ret == 0 means we found what we were searching for, which
@@ -2318,6 +2318,7 @@ void btrfs_orphan_cleanup(struct btrfs_root *root)
                  * find the key and see if we have stuff that matches
                  */
                 if (ret > 0) {
+                        ret = 0;
                         if (path->slots[0] == 0)
                                 break;
                         path->slots[0]--;
@@ -2345,7 +2346,10 @@ void btrfs_orphan_cleanup(struct btrfs_root *root)
                 found_key.type = BTRFS_INODE_ITEM_KEY;
                 found_key.offset = 0;
                 inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL);
-                BUG_ON(IS_ERR(inode));
+                if (IS_ERR(inode)) {
+                        ret = PTR_ERR(inode);
+                        goto out;
+                }
 
                 /*
                  * add this inode to the orphan list so btrfs_orphan_del does
@@ -2363,7 +2367,10 @@ void btrfs_orphan_cleanup(struct btrfs_root *root)
                  */
                 if (is_bad_inode(inode)) {
                         trans = btrfs_start_transaction(root, 0);
-                        BUG_ON(IS_ERR(trans));
+                        if (IS_ERR(trans)) {
+                                ret = PTR_ERR(trans);
+                                goto out;
+                        }
                         btrfs_orphan_del(trans, inode);
                         btrfs_end_transaction(trans, root);
                         iput(inode);
@@ -2378,16 +2385,16 @@ void btrfs_orphan_cleanup(struct btrfs_root *root)
                                 continue;
                         }
                         nr_truncate++;
-                        btrfs_truncate(inode);
+                        ret = btrfs_truncate(inode);
                 } else {
                         nr_unlink++;
                 }
 
                 /* this will do delete_inode and everything for us */
                 iput(inode);
+                if (ret)
+                        goto out;
         }
-        btrfs_free_path(path);
-
         root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
 
         if (root->orphan_block_rsv)
@@ -2396,14 +2403,20 @@ void btrfs_orphan_cleanup(struct btrfs_root *root)
 
         if (root->orphan_block_rsv || root->orphan_item_inserted) {
                 trans = btrfs_join_transaction(root, 1);
-                BUG_ON(IS_ERR(trans));
-                btrfs_end_transaction(trans, root);
+                if (!IS_ERR(trans))
+                        btrfs_end_transaction(trans, root);
         }
 
         if (nr_unlink)
                 printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink);
         if (nr_truncate)
                 printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate);
+
+out:
+        if (ret)
+                printk(KERN_CRIT "btrfs: could not do orphan cleanup %d\n", ret);
+        btrfs_free_path(path);
+        return ret;
 }
 
 /*
@@ -4156,8 +4169,10 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
         if (!IS_ERR(inode) && root != sub_root) {
                 down_read(&root->fs_info->cleanup_work_sem);
                 if (!(inode->i_sb->s_flags & MS_RDONLY))
-                        btrfs_orphan_cleanup(sub_root);
+                        ret = btrfs_orphan_cleanup(sub_root);
                 up_read(&root->fs_info->cleanup_work_sem);
+                if (ret)
+                        inode = ERR_PTR(ret);
         }
 
         return inode;
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 5fdb2abc4fa7..ad9b8c0e930b 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -409,7 +409,9 @@ static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
         if (ret)
                 goto fail;
 
-        btrfs_orphan_cleanup(pending_snapshot->snap);
+        ret = btrfs_orphan_cleanup(pending_snapshot->snap);
+        if (ret)
+                goto fail;
 
         parent = dget_parent(dentry);
         inode = btrfs_lookup_dentry(parent->d_inode, dentry);
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 31ade5802ae8..c863c8447015 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -4209,7 +4209,7 @@ out:
                 if (IS_ERR(fs_root))
                         err = PTR_ERR(fs_root);
                 else
-                        btrfs_orphan_cleanup(fs_root);
+                        err = btrfs_orphan_cleanup(fs_root);
         }
         return err;
 }