cciss: initialize struct scsi_req

The changes in "block: Make most scsi_req_init() calls implicit" mean
that every driver that supports the generic scsi ioctls needs to
call scsi_req_init on newly allocated requests, but that commit didn't
add the call to the ccіss driver.  Fix that to avoid crashes when
udev issues SG_IO commands.

Fixes: ca18d6f7 ("block: Make most scsi_req_init() calls implicit")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/cciss.c

@@ -1944,6 +1944,13 @@ static void cciss_get_serial_no(ctlr_info_t *h, int logvol,
 	return;
 }
 
+static void cciss_initialize_rq(struct request *rq)
+{
+	struct scsi_request *sreq = blk_mq_rq_to_pdu(rq);
+
+	scsi_req_init(sreq);
+}
+
 /*
  * cciss_add_disk sets up the block device queue for a logical drive
  */
@@ -1956,6 +1963,7 @@ static int cciss_add_disk(ctlr_info_t *h, struct gendisk *disk,
 
 	disk->queue->cmd_size = sizeof(struct scsi_request);
 	disk->queue->request_fn = do_cciss_request;
+	disk->queue->initialize_rq_fn = cciss_initialize_rq;
 	disk->queue->queue_lock = &h->lock;
 	queue_flag_set_unlocked(QUEUE_FLAG_SCSI_PASSTHROUGH, disk->queue);
 	if (blk_init_allocated_queue(disk->queue) < 0)