scsi: core: Remove struct scsi_request

Let submitters initialize the scmd->allowed field directly instead of
indirecting through struct scsi_request and remove the now superfluous
structure.

Link: https://lore.kernel.org/r/20220224175552.988286-8-hch@lst.deReviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/scsi_debugfs.c

@@ -33,7 +33,7 @@ static int scsi_flags_show(struct seq_file *m, const unsigned long flags,
 
 void scsi_show_rq(struct seq_file *m, struct request *rq)
 {
-	struct scsi_cmnd *cmd = container_of(scsi_req(rq), typeof(*cmd), req);
+	struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
 	int alloc_ms = jiffies_to_msecs(jiffies - cmd->jiffies_at_alloc);
 	int timeout_ms = jiffies_to_msecs(rq->timeout);
 	char buf[80] = "(?)";

drivers/scsi/scsi_error.c

@@ -2023,12 +2023,10 @@ static void scsi_eh_lock_door(struct scsi_device *sdev)
 {
 	struct scsi_cmnd *scmd;
 	struct request *req;
-	struct scsi_request *rq;
 
 	req = scsi_alloc_request(sdev->request_queue, REQ_OP_DRV_IN, 0);
 	if (IS_ERR(req))
 		return;
-	rq = scsi_req(req);
 	scmd = blk_mq_rq_to_pdu(req);
 
 	scmd->cmnd[0] = ALLOW_MEDIUM_REMOVAL;
@@ -2041,7 +2039,7 @@ static void scsi_eh_lock_door(struct scsi_device *sdev)
 
 	req->rq_flags |= RQF_QUIET;
 	req->timeout = 10 * HZ;
-	rq->retries = 5;
+	scmd->allowed = 5;
 
 	blk_execute_rq_nowait(req, true, eh_lock_door_done);
 }

drivers/scsi/scsi_ioctl.c

@@ -411,7 +411,6 @@ static int sg_io(struct scsi_device *sdev, struct sg_io_hdr *hdr, fmode_t mode)
 	int writing = 0;
 	int at_head = 0;
 	struct request *rq;
-	struct scsi_request *req;
 	struct scsi_cmnd *scmd;
 	struct bio *bio;
 
@@ -440,7 +439,6 @@ static int sg_io(struct scsi_device *sdev, struct sg_io_hdr *hdr, fmode_t mode)
 			     REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
 	if (IS_ERR(rq))
 		return PTR_ERR(rq);
-	req = scsi_req(rq);
 	scmd = blk_mq_rq_to_pdu(rq);
 
 	if (hdr->cmd_len > sizeof(scmd->cmnd)) {
@@ -475,7 +473,7 @@ static int sg_io(struct scsi_device *sdev, struct sg_io_hdr *hdr, fmode_t mode)
 		goto out_put_request;
 
 	bio = rq->bio;
-	req->retries = 0;
+	scmd->allowed = 0;
 
 	start_time = jiffies;
 
@@ -521,7 +519,6 @@ static int sg_scsi_ioctl(struct request_queue *q, fmode_t mode,
 		struct scsi_ioctl_command __user *sic)
 {
 	struct request *rq;
-	struct scsi_request *req;
 	int err;
 	unsigned int in_len, out_len, bytes, opcode, cmdlen;
 	struct scsi_cmnd *scmd;
@@ -555,7 +552,6 @@ static int sg_scsi_ioctl(struct request_queue *q, fmode_t mode,
 		err = PTR_ERR(rq);
 		goto error_free_buffer;
 	}
-	req = scsi_req(rq);
 	scmd = blk_mq_rq_to_pdu(rq);
 
 	cmdlen = COMMAND_SIZE(opcode);
@@ -576,13 +572,13 @@ static int sg_scsi_ioctl(struct request_queue *q, fmode_t mode,
 		goto error;
 
 	/* default.  possible overridden later */
-	req->retries = 5;
+	scmd->allowed = 5;
 
 	switch (opcode) {
 	case SEND_DIAGNOSTIC:
 	case FORMAT_UNIT:
 		rq->timeout = FORMAT_UNIT_TIMEOUT;
-		req->retries = 1;
+		scmd->allowed = 1;
 		break;
 	case START_STOP:
 		rq->timeout = START_STOP_TIMEOUT;
@@ -595,7 +591,7 @@ static int sg_scsi_ioctl(struct request_queue *q, fmode_t mode,
 		break;
 	case READ_DEFECT_DATA:
 		rq->timeout = READ_DEFECT_DATA_TIMEOUT;
-		req->retries = 1;
+		scmd->allowed = 1;
 		break;
 	default:
 		rq->timeout = BLK_DEFAULT_SG_TIMEOUT;

drivers/scsi/scsi_lib.c

@@ -213,7 +213,6 @@ int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 		 int *resid)
 {
 	struct request *req;
-	struct scsi_request *rq;
 	struct scsi_cmnd *scmd;
 	int ret;
 
@@ -224,8 +223,6 @@ int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
-	rq = scsi_req(req);
-
 	if (bufflen) {
 		ret = blk_rq_map_kern(sdev->request_queue, req,
 				      buffer, bufflen, GFP_NOIO);
@@ -235,7 +232,7 @@ int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 	scmd = blk_mq_rq_to_pdu(req);
 	scmd->cmd_len = COMMAND_SIZE(cmd[0]);
 	memcpy(scmd->cmnd, cmd, scmd->cmd_len);
-	rq->retries = retries;
+	scmd->allowed = retries;
 	req->timeout = timeout;
 	req->cmd_flags |= flags;
 	req->rq_flags |= rq_flags | RQF_QUIET;
@@ -1189,7 +1186,6 @@ static blk_status_t scsi_setup_scsi_cmnd(struct scsi_device *sdev,
 	}
 
 	cmd->transfersize = blk_rq_bytes(req);
-	cmd->allowed = scsi_req(req)->retries;
 	return BLK_STS_OK;
 }
 

drivers/scsi/sg.c

@@ -1725,7 +1725,6 @@ sg_start_req(Sg_request *srp, unsigned char *cmd)
 {
 	int res;
 	struct request *rq;
-	struct scsi_request *req;
 	Sg_fd *sfp = srp->parentfp;
 	sg_io_hdr_t *hp = &srp->header;
 	int dxfer_len = (int) hp->dxfer_len;
@@ -1758,7 +1757,6 @@ sg_start_req(Sg_request *srp, unsigned char *cmd)
 	if (IS_ERR(rq))
 		return PTR_ERR(rq);
 	scmd = blk_mq_rq_to_pdu(rq);
-	req = scsi_req(rq);
 
 	if (hp->cmd_len > sizeof(scmd->cmnd)) {
 		blk_mq_free_request(rq);
@@ -1770,7 +1768,7 @@ sg_start_req(Sg_request *srp, unsigned char *cmd)
 
 	srp->rq = rq;
 	rq->end_io_data = srp;
-	req->retries = SG_DEFAULT_RETRIES;
+	scmd->allowed = SG_DEFAULT_RETRIES;
 
 	if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
 		return 0;

drivers/scsi/sr.c

@@ -965,7 +965,6 @@ static int sr_read_cdda_bpc(struct cdrom_device_info *cdi, void __user *ubuf,
 {
 	struct gendisk *disk = cdi->disk;
 	u32 len = nr * CD_FRAMESIZE_RAW;
-	struct scsi_request *req;
 	struct scsi_cmnd *scmd;
 	struct request *rq;
 	struct bio *bio;
@@ -974,7 +973,6 @@ static int sr_read_cdda_bpc(struct cdrom_device_info *cdi, void __user *ubuf,
 	rq = scsi_alloc_request(disk->queue, REQ_OP_DRV_IN, 0);
 	if (IS_ERR(rq))
 		return PTR_ERR(rq);
-	req = scsi_req(rq);
 	scmd = blk_mq_rq_to_pdu(rq);
 
 	ret = blk_rq_map_user(disk->queue, rq, NULL, ubuf, len, GFP_KERNEL);

drivers/scsi/st.c

@@ -539,7 +539,6 @@ static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,
 			   int timeout, int retries)
 {
 	struct request *req;
-	struct scsi_request *rq;
 	struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
 	int err = 0;
 	struct scsi_tape *STp = SRpnt->stp;
@@ -551,7 +550,6 @@ static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 	scmd = blk_mq_rq_to_pdu(req);
-	rq = scsi_req(req);
 	req->rq_flags |= RQF_QUIET;
 
 	mdata->null_mapped = 1;
@@ -580,7 +578,7 @@ static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,
 	scmd->cmd_len = COMMAND_SIZE(cmd[0]);
 	memcpy(scmd->cmnd, cmd, scmd->cmd_len);
 	req->timeout = timeout;
-	rq->retries = retries;
+	scmd->allowed = retries;
 	req->end_io_data = SRpnt;
 
 	blk_execute_rq_nowait(req, true, st_scsi_execute_end);

drivers/target/target_core_pscsi.c

@@ -993,7 +993,7 @@ pscsi_execute_cmd(struct se_cmd *cmd)
 		req->timeout = PS_TIMEOUT_DISK;
 	else
 		req->timeout = PS_TIMEOUT_OTHER;
-	scsi_req(req)->retries = PS_RETRY;
+	scmd->allowed = PS_RETRY;
 
 	cmd->priv = scmd->cmnd;
 

include/scsi/scsi_cmnd.h

@@ -68,7 +68,6 @@ enum scsi_cmnd_submitter {
 } __packed;
 
 struct scsi_cmnd {
-	struct scsi_request req;
 	struct scsi_device *device;
 	struct list_head eh_entry; /* entry for the host eh_abort_list/eh_cmd_q */
 	struct delayed_work abort_work;

include/scsi/scsi_request.h

@@ -4,13 +4,4 @@
 
 #include <linux/blk-mq.h>
 
-struct scsi_request {
-	int		retries;
-};
-
-static inline struct scsi_request *scsi_req(struct request *rq)
-{
-	return blk_mq_rq_to_pdu(rq);
-}
-
 #endif /* _SCSI_SCSI_REQUEST_H */