From 9b3517e9136824346227b7b04f8f7ea1f3a726cc Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Tue, 15 Feb 2011 18:14:25 +0000 Subject: [PATCH] Btrfs: make btrfs_rm_device() fail gracefully If shrinking done as part of the online device removal fails add that device back to the allocation list and increment the rw_devices counter. This fixes two bugs: 1) we could have a perfectly good device out of alloc list for no good reason; 2) in the btrfs consisting of two devices, failure in btrfs_rm_device() could lead to a situation where it was impossible to remove any of the devices because of the "unable to remove the only writeable device" error. Signed-off-by: Ilya Dryomov Signed-off-by: Chris Mason --- fs/btrfs/volumes.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index dadaaa8005c8..f31c33119bb6 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -1337,11 +1337,11 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path) ret = btrfs_shrink_device(device, 0); if (ret) - goto error_brelse; + goto error_undo; ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device); if (ret) - goto error_brelse; + goto error_undo; device->in_fs_metadata = 0; @@ -1415,6 +1415,13 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path) mutex_unlock(&root->fs_info->volume_mutex); mutex_unlock(&uuid_mutex); return ret; +error_undo: + if (device->writeable) { + list_add(&device->dev_alloc_list, + &root->fs_info->fs_devices->alloc_list); + root->fs_info->fs_devices->rw_devices++; + } + goto error_brelse; } /*