Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 70bc7088 authored by Anand Jain's avatar Anand Jain Committed by David Sterba
Browse files

btrfs: refactor btrfs_free_stale_devices() to get return value 



Preparatory patch to add ioctl that allows to forget a device (ie.
reverse of scan).

Refactors btrfs_free_stale_devices() to obtain return status. As this
function can fail if it can't find the given path (returns -ENOENT) or
trying to delete a mounted device (returns -EBUSY).

Signed-off-by: default avatarAnand Jain <anand.jain@oracle.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent e4319cd9

fs/btrfs/volumes.c

+31 −15
Original line number Diff line number Diff line
@@ -734,6 +734,17 @@ static void pending_bios_fn(struct btrfs_work *work) 
	run_scheduled_bios(device);

}



static bool device_path_matched(const char *path, struct btrfs_device *device)

{

	int found;



	rcu_read_lock();

	found = strcmp(rcu_str_deref(device->name), path);

	rcu_read_unlock();



	return found == 0;

}



/*

 *  Search and remove all stale (devices which are not mounted) devices.

 *  When both inputs are NULL, it will search and release all stale devices.
@@ -741,52 +752,57 @@ static void pending_bios_fn(struct btrfs_work *work) 
 *		matching this path only.

 *  skip_dev:	Optional. Will skip this device when searching for the stale

 *		devices.

 *  Return:	0 for success or if @path is NULL.

 * 		-EBUSY if @path is a mounted device.

 * 		-ENOENT if @path does not match any device in the list.

 */

static void btrfs_free_stale_devices(const char *path,

static int btrfs_free_stale_devices(const char *path,

				     struct btrfs_device *skip_device)

{

	struct btrfs_fs_devices *fs_devices, *tmp_fs_devices;

	struct btrfs_device *device, *tmp_device;

	int ret = 0;



	if (path)

		ret = -ENOENT;



	list_for_each_entry_safe(fs_devices, tmp_fs_devices, &fs_uuids, fs_list) {

		mutex_lock(&fs_devices->device_list_mutex);

		if (fs_devices->opened) {

			mutex_unlock(&fs_devices->device_list_mutex);

			continue;

		}



		mutex_lock(&fs_devices->device_list_mutex);

		list_for_each_entry_safe(device, tmp_device,

					 &fs_devices->devices, dev_list) {

			int not_found = 0;



			if (skip_device && skip_device == device)

				continue;

			if (path && !device->name)

				continue;



			rcu_read_lock();

			if (path)

				not_found = strcmp(rcu_str_deref(device->name),

						   path);

			rcu_read_unlock();

			if (not_found)

			if (path && !device_path_matched(path, device))

				continue;

			if (fs_devices->opened) {

				/* for an already deleted device return 0 */

				if (path && ret != 0)

					ret = -EBUSY;

				break;

			}



			/* delete the stale device */

			fs_devices->num_devices--;

			list_del(&device->dev_list);

			btrfs_free_device(device);



			ret = 0;

			if (fs_devices->num_devices == 0)

				break;

		}

		mutex_unlock(&fs_devices->device_list_mutex);



		if (fs_devices->num_devices == 0) {

			btrfs_sysfs_remove_fsid(fs_devices);

			list_del(&fs_devices->fs_list);

			free_fs_devices(fs_devices);

		}

	}



	return ret;

}



static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,