block: seperate bio/request unplug and sync bits

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

block/blk-core.c

@@ -1125,6 +1125,8 @@ void init_request_from_bio(struct request *req, struct bio *bio)
 
 	if (bio_sync(bio))
 		req->cmd_flags |= REQ_RW_SYNC;
+	if (bio_unplug(bio))
+		req->cmd_flags |= REQ_UNPLUG;
 	if (bio_rw_meta(bio))
 		req->cmd_flags |= REQ_RW_META;
 
@@ -1141,6 +1143,7 @@ static int __make_request(struct request_queue *q, struct bio *bio)
 	int el_ret, nr_sectors;
 	const unsigned short prio = bio_prio(bio);
 	const int sync = bio_sync(bio);
+	const int unplug = bio_unplug(bio);
 	int rw_flags;
 
 	nr_sectors = bio_sectors(bio);
@@ -1244,7 +1247,7 @@ static int __make_request(struct request_queue *q, struct bio *bio)
 		blk_plug_device(q);
 	add_request(q, req);
 out:
-	if (sync || blk_queue_nonrot(q))
+	if (unplug || blk_queue_nonrot(q))
 		__generic_unplug_device(q);
 	spin_unlock_irq(q->queue_lock);
 	return 0;

include/linux/bio.h

@@ -163,12 +163,15 @@ struct bio {
 #define BIO_RW		0	/* Must match RW in req flags (blkdev.h) */
 #define BIO_RW_AHEAD	1	/* Must match FAILFAST in req flags */
 #define BIO_RW_BARRIER	2
-#define BIO_RW_SYNC	3
-#define BIO_RW_META	4
-#define BIO_RW_DISCARD	5
-#define BIO_RW_FAILFAST_DEV		6
-#define BIO_RW_FAILFAST_TRANSPORT	7
-#define BIO_RW_FAILFAST_DRIVER		8
+#define BIO_RW_SYNCIO	3
+#define BIO_RW_UNPLUG	4
+#define BIO_RW_META	5
+#define BIO_RW_DISCARD	6
+#define BIO_RW_FAILFAST_DEV		7
+#define BIO_RW_FAILFAST_TRANSPORT	8
+#define BIO_RW_FAILFAST_DRIVER		9
+
+#define BIO_RW_SYNC	(BIO_RW_SYNCIO | BIO_RW_UNPLUG)
 
 /*
  * upper 16 bits of bi_rw define the io priority of this bio
@@ -194,7 +197,8 @@ struct bio {
 #define bio_segments(bio)	((bio)->bi_vcnt - (bio)->bi_idx)
 #define bio_sectors(bio)	((bio)->bi_size >> 9)
 #define bio_barrier(bio)	((bio)->bi_rw & (1 << BIO_RW_BARRIER))
-#define bio_sync(bio)		((bio)->bi_rw & (1 << BIO_RW_SYNC))
+#define bio_sync(bio)		((bio)->bi_rw & (1 << BIO_RW_SYNCIO))
+#define bio_unplug(bio)		((bio)->bi_rw & (1 << BIO_RW_UNPLUG))
 #define bio_failfast_dev(bio)	((bio)->bi_rw &	(1 << BIO_RW_FAILFAST_DEV))
 #define bio_failfast_transport(bio)	\
 	((bio)->bi_rw & (1 << BIO_RW_FAILFAST_TRANSPORT))

include/linux/blkdev.h

@@ -108,6 +108,7 @@ enum rq_flag_bits {
 	__REQ_RW_META,		/* metadata io request */
 	__REQ_COPY_USER,	/* contains copies of user pages */
 	__REQ_INTEGRITY,	/* integrity metadata has been remapped */
+	__REQ_UNPLUG,		/* unplug queue on submission */
 	__REQ_NR_BITS,		/* stops here */
 };
 
@@ -134,6 +135,7 @@ enum rq_flag_bits {
 #define REQ_RW_META	(1 << __REQ_RW_META)
 #define REQ_COPY_USER	(1 << __REQ_COPY_USER)
 #define REQ_INTEGRITY	(1 << __REQ_INTEGRITY)
+#define REQ_UNPLUG	(1 << __REQ_UNPLUG)
 
 #define BLK_MAX_CDB	16