From: John Garry <[email protected]> Add mpath_bdev_get_unique_id() as a multipath block device .get_unique_id handler.
Signed-off-by: John Garry <[email protected]> --- lib/multipath.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/lib/multipath.c b/lib/multipath.c index 2017c4d0a210c..66b3338cf8389 100644 --- a/lib/multipath.c +++ b/lib/multipath.c @@ -454,6 +454,27 @@ static void mpath_bdev_release(struct gendisk *disk) mpath_put_head(mpath_head); } +static int mpath_bdev_get_unique_id(struct gendisk *disk, u8 id[16], + enum blk_unique_id type) +{ + struct mpath_head *mpath_head = mpath_gendisk_to_head(disk); + int srcu_idx, ret = -EWOULDBLOCK; + struct mpath_device *mpath_device; + + srcu_idx = srcu_read_lock(&mpath_head->srcu); + mpath_device = mpath_find_path(mpath_head); + if (mpath_device) { + if (mpath_device->disk->fops->get_unique_id) + ret = mpath_device->disk->fops->get_unique_id( + mpath_device->disk, id, type); + else + ret = 0; /* referencing __dm_get_unique_id() */ + } + srcu_read_unlock(&mpath_head->srcu, srcu_idx); + + return ret; +} + static int mpath_bdev_ioctl(struct block_device *bdev, blk_mode_t mode, unsigned int cmd, unsigned long arg) { @@ -521,6 +542,7 @@ const struct block_device_operations mpath_ops = { * avoid their custom compat_ioctl implementation. */ .compat_ioctl = blkdev_compat_ptr_ioctl, + .get_unique_id = mpath_bdev_get_unique_id, .getgeo = mpath_bdev_getgeo, }; EXPORT_SYMBOL_GPL(mpath_ops); -- 2.43.7
