block: bdev_stack_limits wrapper

DM does not want to know about partition offsets.  Add a partition-aware
wrapper that DM can use when stacking block devices.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index a41bcc8e140f..5c8018977efa 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -938,6 +938,8 @@ extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
 extern void blk_set_default_limits(struct queue_limits *lim);
 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
                             sector_t offset);
+extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
+                            sector_t offset);
 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
                               sector_t offset);
 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);