Commit 0c1daee0 authored by Xiao Guangrong's avatar Xiao Guangrong Committed by Chris Mason
Browse files

Btrfs: fix the race between remove dev and alloc chunk 



On remove device path, it updates device->dev_alloc_list but does not hold
chunk lock

Signed-off-by: default avatarXiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent c9513edb

fs/btrfs/volumes.c

+6 −0
Original line number Diff line number Diff line
@@ -1291,7 +1291,9 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path) 
	}



	if (device->writeable) {

		lock_chunks(root);

		list_del_init(&device->dev_alloc_list);

		unlock_chunks(root);

		root->fs_info->fs_devices->rw_devices--;

	}
@@ -1345,7 +1347,9 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path) 
		}

		fs_devices->seed = device->fs_devices->seed;

		device->fs_devices->seed = NULL;

		lock_chunks(root);

		__btrfs_close_devices(device->fs_devices);

		unlock_chunks(root);

		free_fs_devices(device->fs_devices);

	}
@@ -1377,8 +1381,10 @@ out: 
	return ret;

error_undo:

	if (device->writeable) {

		lock_chunks(root);

		list_add(&device->dev_alloc_list,

			 &root->fs_info->fs_devices->alloc_list);

		unlock_chunks(root);

		root->fs_info->fs_devices->rw_devices++;

	}

	goto error_brelse;