block: introduce blk_rq_is_passthrough

This can be used to check for fs vs non-fs requests and basically
removes all knowledge of BLOCK_PC specific from the block layer,
as well as preparing for removing the cmd_type field in struct request.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

3 files changed, 14 insertions, 8 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index e4c5f284fe2d..7121be081517 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -242,6 +242,11 @@ struct request {
 	struct request *next_rq;
 };
 
+static inline bool blk_rq_is_passthrough(struct request *rq)
+{
+	return rq->cmd_type != REQ_TYPE_FS;
+}
+
 static inline unsigned short req_get_ioprio(struct request *req)
 {
 	return req->ioprio;
@@ -698,9 +703,10 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
 	((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
 			     REQ_FAILFAST_DRIVER))
 
-#define blk_account_rq(rq) \
-	(((rq)->rq_flags & RQF_STARTED) && \
-	 ((rq)->cmd_type == REQ_TYPE_FS))
+static inline bool blk_account_rq(struct request *rq)
+{
+	return (rq->rq_flags & RQF_STARTED) && !blk_rq_is_passthrough(rq);
+}
 
 #define blk_rq_cpu_valid(rq)	((rq)->cpu != -1)
 #define blk_bidi_rq(rq)		((rq)->next_rq != NULL)
@@ -775,7 +781,7 @@ static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
 
 static inline bool rq_mergeable(struct request *rq)
 {
-	if (rq->cmd_type != REQ_TYPE_FS)
+	if (blk_rq_is_passthrough(rq))
 		return false;
 
 	if (req_op(rq) == REQ_OP_FLUSH)
@@ -1049,7 +1055,7 @@ static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
 {
 	struct request_queue *q = rq->q;
 
-	if (unlikely(rq->cmd_type != REQ_TYPE_FS))
+	if (blk_rq_is_passthrough(rq))
 		return q->limits.max_hw_sectors;
 
 	if (!q->limits.chunk_sectors ||
diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h
index a143a67a6f33..341f9418bd68 100644
--- a/include/linux/blktrace_api.h
+++ b/include/linux/blktrace_api.h
@@ -114,12 +114,12 @@ extern void blk_fill_rwbs(char *rwbs, unsigned int op, int bytes);
 
 static inline sector_t blk_rq_trace_sector(struct request *rq)
 {
-	return (rq->cmd_type != REQ_TYPE_FS) ? 0 : blk_rq_pos(rq);
+	return blk_rq_is_passthrough(rq) ? 0 : blk_rq_pos(rq);
 }
 
 static inline unsigned int blk_rq_trace_nr_sectors(struct request *rq)
 {
-	return (rq->cmd_type != REQ_TYPE_FS) ? 0 : blk_rq_sectors(rq);
+	return blk_rq_is_passthrough(rq) ? 0 : blk_rq_sectors(rq);
 }
 
 #endif
diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h
index f708f1acfc50..b379f93a2c48 100644
--- a/include/scsi/scsi_cmnd.h
+++ b/include/scsi/scsi_cmnd.h
@@ -151,7 +151,7 @@ static inline void *scsi_cmd_priv(struct scsi_cmnd *cmd)
 	return cmd + 1;
 }
 
-/* make sure not to use it with REQ_TYPE_BLOCK_PC commands */
+/* make sure not to use it with passthrough commands */
 static inline struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd)
 {
 	return *(struct scsi_driver **)cmd->request->rq_disk->private_data;