scsi: block: remove req->special

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Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

block/blk-mq.c

@@ -331,7 +331,6 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 	rq->nr_integrity_segments = 0;
 #endif
-	rq->special = NULL;
 	/* tag was already set */
 	rq->extra_len = 0;
 	WRITE_ONCE(rq->deadline, 0);

drivers/scsi/sd.c

@@ -1171,8 +1171,6 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd)
 	if (ret != BLK_STS_OK)
 		return ret;
 
-	WARN_ON_ONCE(cmd != rq->special);
-
 	if (!scsi_device_online(sdp) || sdp->changed) {
 		scmd_printk(KERN_ERR, cmd, "device offline or changed\n");
 		return BLK_STS_IOERR;

include/linux/blkdev.h

@@ -216,8 +216,6 @@ struct request {
 	unsigned short write_hint;
 	unsigned short ioprio;
 
-	void *special;		/* opaque pointer available for LLD use */
-
 	unsigned int extra_len;	/* length of alignment and padding */
 
 	enum mq_rq_state state;