Commit 444e7516 authored by David Sterba's avatar David Sterba
Browse files

btrfs: sysfs: introduce helper for syncing bits with sysfs files 



The files under /sys/fs/UUID/features get out of sync with the actual
incompat bits set for the filesystem if they change after mount. We're
going to sync them and need a helper to do that.

Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 3b5bb73b

fs/btrfs/sysfs.c

+30 −0
Original line number Diff line number Diff line
@@ -782,6 +782,36 @@ int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info) 
	return error;

}





/*

 * Change per-fs features in /sys/fs/btrfs/UUID/features to match current

 * values in superblock. Call after any changes to incompat/compat_ro flags

 */

void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,

		u64 bit, enum btrfs_feature_set set)

{

	struct btrfs_fs_devices *fs_devs;

	struct kobject *fsid_kobj;

	u64 features;

	int ret;



	if (!fs_info)

		return;



	features = get_features(fs_info, set);

	ASSERT(bit & supported_feature_masks[set]);



	fs_devs = fs_info->fs_devices;

	fsid_kobj = &fs_devs->fsid_kobj;



	/*

	 * FIXME: this is too heavy to update just one value, ideally we'd like

	 * to use sysfs_update_group but some refactoring is needed first.

	 */

	sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);

	ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);

}



static int btrfs_init_debugfs(void)

{

#ifdef CONFIG_DEBUG_FS

fs/btrfs/sysfs.h

+3 −0
Original line number Diff line number Diff line
@@ -90,4 +90,7 @@ int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs, 
				struct kobject *parent);

int btrfs_sysfs_add_device(struct btrfs_fs_devices *fs_devs);

void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs);

void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,

		u64 bit, enum btrfs_feature_set set);



#endif /* _BTRFS_SYSFS_H_ */