scsi: core: Move the resid_len field from struct scsi_request to struct scsi_cmnd

Prepare for removing the scsi_request structure by moving the resid_len
field to struct scsi_cmnd.

Link: https://lore.kernel.org/r/20220224175552.988286-6-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_bsg.c

@@ -88,9 +88,9 @@ static int scsi_bsg_sg_io_fn(struct request_queue *q, struct sg_io_v4 *hdr,
 	}
 
 	if (rq_data_dir(rq) == READ)
-		hdr->din_resid = sreq->resid_len;
+		hdr->din_resid = scmd->resid_len;
 	else
-		hdr->dout_resid = sreq->resid_len;
+		hdr->dout_resid = scmd->resid_len;
 
 	blk_rq_unmap_user(bio);
 

drivers/scsi/scsi_error.c

@@ -1005,7 +1005,7 @@ void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,
 	ses->data_direction = scmd->sc_data_direction;
 	ses->sdb = scmd->sdb;
 	ses->result = scmd->result;
-	ses->resid_len = scmd->req.resid_len;
+	ses->resid_len = scmd->resid_len;
 	ses->underflow = scmd->underflow;
 	ses->prot_op = scmd->prot_op;
 	ses->eh_eflags = scmd->eh_eflags;
@@ -1016,7 +1016,7 @@ void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,
 	memset(scmd->cmnd, 0, sizeof(scmd->cmnd));
 	memset(&scmd->sdb, 0, sizeof(scmd->sdb));
 	scmd->result = 0;
-	scmd->req.resid_len = 0;
+	scmd->resid_len = 0;
 
 	if (sense_bytes) {
 		scmd->sdb.length = min_t(unsigned, SCSI_SENSE_BUFFERSIZE,
@@ -1069,7 +1069,7 @@ void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses)
 	scmd->sc_data_direction = ses->data_direction;
 	scmd->sdb = ses->sdb;
 	scmd->result = ses->result;
-	scmd->req.resid_len = ses->resid_len;
+	scmd->resid_len = ses->resid_len;
 	scmd->underflow = ses->underflow;
 	scmd->prot_op = ses->prot_op;
 	scmd->eh_eflags = ses->eh_eflags;

drivers/scsi/scsi_ioctl.c

@@ -386,7 +386,7 @@ static int scsi_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
 	hdr->info = 0;
 	if (hdr->masked_status || hdr->host_status || hdr->driver_status)
 		hdr->info |= SG_INFO_CHECK;
-	hdr->resid = req->resid_len;
+	hdr->resid = scmd->resid_len;
 	hdr->sb_len_wr = 0;
 
 	if (scmd->sense_len && hdr->sbp) {

drivers/scsi/scsi_lib.c

@@ -251,11 +251,11 @@ int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 	 * is invalid.  Prevent the garbage from being misinterpreted
 	 * and prevent security leaks by zeroing out the excess data.
 	 */
-	if (unlikely(rq->resid_len > 0 && rq->resid_len <= bufflen))
-		memset(buffer + (bufflen - rq->resid_len), 0, rq->resid_len);
+	if (unlikely(scmd->resid_len > 0 && scmd->resid_len <= bufflen))
+		memset(buffer + bufflen - scmd->resid_len, 0, scmd->resid_len);
 
 	if (resid)
-		*resid = rq->resid_len;
+		*resid = scmd->resid_len;
 	if (sense && scmd->sense_len)
 		memcpy(sense, scmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
 	if (sshdr)

drivers/scsi/sg.c

@@ -1346,7 +1346,7 @@ sg_rq_end_io(struct request *rq, blk_status_t status)
 
 	sense = scmd->sense_buffer;
 	result = req->result;
-	resid = req->resid_len;
+	resid = scmd->resid_len;
 
 	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
 				      "sg_cmd_done: pack_id=%d, res=0x%x\n",

drivers/scsi/st.c

@@ -521,7 +521,7 @@ static void st_scsi_execute_end(struct request *req, blk_status_t status)
 	struct bio *tmp;
 
 	STp->buffer->cmdstat.midlevel_result = SRpnt->result = rq->result;
-	STp->buffer->cmdstat.residual = rq->resid_len;
+	STp->buffer->cmdstat.residual = scmd->resid_len;
 
 	st_do_stats(STp, req);
 

drivers/target/target_core_pscsi.c

@@ -1046,7 +1046,7 @@ static void pscsi_req_done(struct request *req, blk_status_t status)
 	switch (host_byte(result)) {
 	case DID_OK:
 		target_complete_cmd_with_length(cmd, scsi_status,
-			cmd->data_length - scsi_req(req)->resid_len);
+			cmd->data_length - scmd->resid_len);
 		break;
 	default:
 		pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"

include/scsi/scsi_cmnd.h

@@ -111,7 +111,7 @@ struct scsi_cmnd {
 				   (ie, between disconnect / 
 				   reconnects.   Probably == sector
 				   size */
-
+	unsigned resid_len;	/* residual count */
 	unsigned sense_len;
 	unsigned char *sense_buffer;
 				/* obtained by REQUEST SENSE when
@@ -200,12 +200,12 @@ static inline unsigned scsi_bufflen(struct scsi_cmnd *cmd)
 
 static inline void scsi_set_resid(struct scsi_cmnd *cmd, unsigned int resid)
 {
-	cmd->req.resid_len = resid;
+	cmd->resid_len = resid;
 }
 
 static inline unsigned int scsi_get_resid(struct scsi_cmnd *cmd)
 {
-	return cmd->req.resid_len;
+	return cmd->resid_len;
 }
 
 #define scsi_for_each_sg(cmd, sg, nseg, __i)			\

include/scsi/scsi_request.h

@@ -6,7 +6,6 @@
 
 struct scsi_request {
 	int		result;
-	unsigned int	resid_len;	/* residual count */
 	int		retries;
 };