scsi: core: Add struct for args to execution functions

Move the SCSI execution functions to use a struct for passing in optional
args. This commit adds the new struct, temporarily converts scsi_execute()
and scsi_execute_req() ands a new helper, scsi_execute_cmd(), which takes
the scsi_exec_args struct.

There should be no change in behavior. We no longer allow users to pass in
any request->rq_flags value, but they were only passing in RQF_PM which we
do support by allowing users to pass in the BLK_MQ_REQ flags used by
blk_mq_alloc_request().

Subsequent commits will convert scsi_execute() and scsi_execute_req() users
to the new helpers then remove scsi_execute() and scsi_execute_req().

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 37 insertions, 14 deletions

diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 3642b8e3928b..f6b33c6c1064 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -455,28 +455,51 @@ extern const char *scsi_device_state_name(enum scsi_device_state);
 extern int scsi_is_sdev_device(const struct device *);
 extern int scsi_is_target_device(const struct device *);
 extern void scsi_sanitize_inquiry_string(unsigned char *s, int len);
-extern int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
-			int data_direction, void *buffer, unsigned bufflen,
-			unsigned char *sense, struct scsi_sense_hdr *sshdr,
-			int timeout, int retries, blk_opf_t flags,
-			req_flags_t rq_flags, int *resid);
+
+/* Optional arguments to scsi_execute_cmd */
+struct scsi_exec_args {
+	unsigned char *sense;		/* sense buffer */
+	unsigned int sense_len;		/* sense buffer len */
+	struct scsi_sense_hdr *sshdr;	/* decoded sense header */
+	blk_mq_req_flags_t req_flags;	/* BLK_MQ_REQ flags */
+	int *resid;			/* residual length */
+};
+
+int scsi_execute_cmd(struct scsi_device *sdev, const unsigned char *cmd,
+		     blk_opf_t opf, void *buffer, unsigned int bufflen,
+		     int timeout, int retries,
+		     const struct scsi_exec_args *args);
+
 /* Make sure any sense buffer is the correct size. */
-#define scsi_execute(sdev, cmd, data_direction, buffer, bufflen, sense,	\
-		     sshdr, timeout, retries, flags, rq_flags, resid)	\
+#define scsi_execute(_sdev, _cmd, _data_dir, _buffer, _bufflen, _sense,	\
+		     _sshdr, _timeout, _retries, _flags, _rq_flags,	\
+		     _resid)						\
 ({									\
-	BUILD_BUG_ON((sense) != NULL &&					\
-		     sizeof(sense) != SCSI_SENSE_BUFFERSIZE);		\
-	__scsi_execute(sdev, cmd, data_direction, buffer, bufflen,	\
-		       sense, sshdr, timeout, retries, flags, rq_flags,	\
-		       resid);						\
+	scsi_execute_cmd(_sdev, _cmd, (_data_dir == DMA_TO_DEVICE ?	\
+			 REQ_OP_DRV_OUT : REQ_OP_DRV_IN) | _flags,	\
+			 _buffer, _bufflen, _timeout, _retries,	\
+			 &(struct scsi_exec_args) {			\
+				.sense = _sense,			\
+				.sshdr = _sshdr,			\
+				.req_flags = _rq_flags & RQF_PM  ?	\
+						BLK_MQ_REQ_PM : 0,	\
+				.resid = _resid,			\
+			 });						\
 })
+
 static inline int scsi_execute_req(struct scsi_device *sdev,
 	const unsigned char *cmd, int data_direction, void *buffer,
 	unsigned bufflen, struct scsi_sense_hdr *sshdr, int timeout,
 	int retries, int *resid)
 {
-	return scsi_execute(sdev, cmd, data_direction, buffer,
-		bufflen, NULL, sshdr, timeout, retries,  0, 0, resid);
+	return scsi_execute_cmd(sdev, cmd,
+				data_direction == DMA_TO_DEVICE ?
+				REQ_OP_DRV_OUT : REQ_OP_DRV_IN, buffer,
+				bufflen, timeout, retries,
+				&(struct scsi_exec_args) {
+					.sshdr = sshdr,
+					.resid = resid,
+				});
 }
 extern void sdev_disable_disk_events(struct scsi_device *sdev);
 extern void sdev_enable_disk_events(struct scsi_device *sdev);