block: split out request-only flags into a new namespace

A lot of the REQ_* flags are only used on struct requests, and only of
use to the block layer and a few drivers that dig into struct request
internals.

This patch adds a new req_flags_t rq_flags field to struct request for
them, and thus dramatically shrinks the number of common requests.  It
also removes the unfortunate situation where we have to fit the fields
from the same enum into 32 bits for struct bio and 64 bits for
struct request.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Shaun Tancheff <shaun.tancheff@seagate.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

9 files changed, 78 insertions, 77 deletions

diff --git a/block/blk-core.c b/block/blk-core.c
index e4eda5d2aa56..fd416651a676 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -145,13 +145,13 @@ static void req_bio_endio(struct request *rq, struct bio *bio,
 	if (error)
 		bio->bi_error = error;
 
-	if (unlikely(rq->cmd_flags & REQ_QUIET))
+	if (unlikely(rq->rq_flags & RQF_QUIET))
 		bio_set_flag(bio, BIO_QUIET);
 
 	bio_advance(bio, nbytes);
 
 	/* don't actually finish bio if it's part of flush sequence */
-	if (bio->bi_iter.bi_size == 0 && !(rq->cmd_flags & REQ_FLUSH_SEQ))
+	if (bio->bi_iter.bi_size == 0 && !(rq->rq_flags & RQF_FLUSH_SEQ))
 		bio_endio(bio);
 }
 
@@ -899,7 +899,7 @@ EXPORT_SYMBOL(blk_get_queue);
 
 static inline void blk_free_request(struct request_list *rl, struct request *rq)
 {
-	if (rq->cmd_flags & REQ_ELVPRIV) {
+	if (rq->rq_flags & RQF_ELVPRIV) {
 		elv_put_request(rl->q, rq);
 		if (rq->elv.icq)
 			put_io_context(rq->elv.icq->ioc);
@@ -961,14 +961,14 @@ static void __freed_request(struct request_list *rl, int sync)
  * A request has just been released.  Account for it, update the full and
  * congestion status, wake up any waiters.   Called under q->queue_lock.
  */
-static void freed_request(struct request_list *rl, int op, unsigned int flags)
+static void freed_request(struct request_list *rl, bool sync,
+		req_flags_t rq_flags)
 {
 	struct request_queue *q = rl->q;
-	int sync = rw_is_sync(op, flags);
 
 	q->nr_rqs[sync]--;
 	rl->count[sync]--;
-	if (flags & REQ_ELVPRIV)
+	if (rq_flags & RQF_ELVPRIV)
 		q->nr_rqs_elvpriv--;
 
 	__freed_request(rl, sync);
@@ -1079,6 +1079,7 @@ static struct request *__get_request(struct request_list *rl, int op,
 	struct io_cq *icq = NULL;
 	const bool is_sync = rw_is_sync(op, op_flags) != 0;
 	int may_queue;
+	req_flags_t rq_flags = RQF_ALLOCED;
 
 	if (unlikely(blk_queue_dying(q)))
 		return ERR_PTR(-ENODEV);
@@ -1127,7 +1128,7 @@ static struct request *__get_request(struct request_list *rl, int op,
 
 	/*
 	 * Decide whether the new request will be managed by elevator.  If
-	 * so, mark @op_flags and increment elvpriv.  Non-zero elvpriv will
+	 * so, mark @rq_flags and increment elvpriv.  Non-zero elvpriv will
 	 * prevent the current elevator from being destroyed until the new
 	 * request is freed.  This guarantees icq's won't be destroyed and
 	 * makes creating new ones safe.
@@ -1136,14 +1137,14 @@ static struct request *__get_request(struct request_list *rl, int op,
 	 * it will be created after releasing queue_lock.
 	 */
 	if (blk_rq_should_init_elevator(bio) && !blk_queue_bypass(q)) {
-		op_flags |= REQ_ELVPRIV;
+		rq_flags |= RQF_ELVPRIV;
 		q->nr_rqs_elvpriv++;
 		if (et->icq_cache && ioc)
 			icq = ioc_lookup_icq(ioc, q);
 	}
 
 	if (blk_queue_io_stat(q))
-		op_flags |= REQ_IO_STAT;
+		rq_flags |= RQF_IO_STAT;
 	spin_unlock_irq(q->queue_lock);
 
 	/* allocate and init request */
@@ -1153,10 +1154,11 @@ static struct request *__get_request(struct request_list *rl, int op,
 
 	blk_rq_init(q, rq);
 	blk_rq_set_rl(rq, rl);
-	req_set_op_attrs(rq, op, op_flags | REQ_ALLOCED);
+	req_set_op_attrs(rq, op, op_flags);
+	rq->rq_flags = rq_flags;
 
 	/* init elvpriv */
-	if (op_flags & REQ_ELVPRIV) {
+	if (rq_flags & RQF_ELVPRIV) {
 		if (unlikely(et->icq_cache && !icq)) {
 			if (ioc)
 				icq = ioc_create_icq(ioc, q, gfp_mask);
@@ -1195,7 +1197,7 @@ fail_elvpriv:
 	printk_ratelimited(KERN_WARNING "%s: dev %s: request aux data allocation failed, iosched may be disturbed\n",
 			   __func__, dev_name(q->backing_dev_info.dev));
 
-	rq->cmd_flags &= ~REQ_ELVPRIV;
+	rq->rq_flags &= ~RQF_ELVPRIV;
 	rq->elv.icq = NULL;
 
 	spin_lock_irq(q->queue_lock);
@@ -1212,7 +1214,7 @@ fail_alloc:
 	 * queue, but this is pretty rare.
 	 */
 	spin_lock_irq(q->queue_lock);
-	freed_request(rl, op, op_flags);
+	freed_request(rl, is_sync, rq_flags);
 
 	/*
 	 * in the very unlikely event that allocation failed and no
@@ -1347,7 +1349,7 @@ void blk_requeue_request(struct request_queue *q, struct request *rq)
 	blk_clear_rq_complete(rq);
 	trace_block_rq_requeue(q, rq);
 
-	if (rq->cmd_flags & REQ_QUEUED)
+	if (rq->rq_flags & RQF_QUEUED)
 		blk_queue_end_tag(q, rq);
 
 	BUG_ON(blk_queued_rq(rq));
@@ -1409,7 +1411,7 @@ EXPORT_SYMBOL_GPL(part_round_stats);
 #ifdef CONFIG_PM
 static void blk_pm_put_request(struct request *rq)
 {
-	if (rq->q->dev && !(rq->cmd_flags & REQ_PM) && !--rq->q->nr_pending)
+	if (rq->q->dev && !(rq->rq_flags & RQF_PM) && !--rq->q->nr_pending)
 		pm_runtime_mark_last_busy(rq->q->dev);
 }
 #else
@@ -1421,6 +1423,8 @@ static inline void blk_pm_put_request(struct request *rq) {}
  */
 void __blk_put_request(struct request_queue *q, struct request *req)
 {
+	req_flags_t rq_flags = req->rq_flags;
+
 	if (unlikely(!q))
 		return;
 
@@ -1440,16 +1444,15 @@ void __blk_put_request(struct request_queue *q, struct request *req)
 	 * Request may not have originated from ll_rw_blk. if not,
 	 * it didn't come out of our reserved rq pools
 	 */
-	if (req->cmd_flags & REQ_ALLOCED) {
-		unsigned int flags = req->cmd_flags;
-		int op = req_op(req);
+	if (rq_flags & RQF_ALLOCED) {
 		struct request_list *rl = blk_rq_rl(req);
+		bool sync = rw_is_sync(req_op(req), req->cmd_flags);
 
 		BUG_ON(!list_empty(&req->queuelist));
 		BUG_ON(ELV_ON_HASH(req));
 
 		blk_free_request(rl, req);
-		freed_request(rl, op, flags);
+		freed_request(rl, sync, rq_flags);
 		blk_put_rl(rl);
 	}
 }
@@ -2214,7 +2217,7 @@ unsigned int blk_rq_err_bytes(const struct request *rq)
 	unsigned int bytes = 0;
 	struct bio *bio;
 
-	if (!(rq->cmd_flags & REQ_MIXED_MERGE))
+	if (!(rq->rq_flags & RQF_MIXED_MERGE))
 		return blk_rq_bytes(rq);
 
 	/*
@@ -2257,7 +2260,7 @@ void blk_account_io_done(struct request *req)
 	 * normal IO on queueing nor completion.  Accounting the
 	 * containing request is enough.
 	 */
-	if (blk_do_io_stat(req) && !(req->cmd_flags & REQ_FLUSH_SEQ)) {
+	if (blk_do_io_stat(req) && !(req->rq_flags & RQF_FLUSH_SEQ)) {
 		unsigned long duration = jiffies - req->start_time;
 		const int rw = rq_data_dir(req);
 		struct hd_struct *part;
@@ -2285,7 +2288,7 @@ static struct request *blk_pm_peek_request(struct request_queue *q,
 					   struct request *rq)
 {
 	if (q->dev && (q->rpm_status == RPM_SUSPENDED ||
-	    (q->rpm_status != RPM_ACTIVE && !(rq->cmd_flags & REQ_PM))))
+	    (q->rpm_status != RPM_ACTIVE && !(rq->rq_flags & RQF_PM))))
 		return NULL;
 	else
 		return rq;
@@ -2361,13 +2364,13 @@ struct request *blk_peek_request(struct request_queue *q)
 		if (!rq)
 			break;
 
-		if (!(rq->cmd_flags & REQ_STARTED)) {
+		if (!(rq->rq_flags & RQF_STARTED)) {
 			/*
 			 * This is the first time the device driver
 			 * sees this request (possibly after
 			 * requeueing).  Notify IO scheduler.
 			 */
-			if (rq->cmd_flags & REQ_SORTED)
+			if (rq->rq_flags & RQF_SORTED)
 				elv_activate_rq(q, rq);
 
 			/*
@@ -2375,7 +2378,7 @@ struct request *blk_peek_request(struct request_queue *q)
 			 * it, a request that has been delayed should
 			 * not be passed by new incoming requests
 			 */
-			rq->cmd_flags |= REQ_STARTED;
+			rq->rq_flags |= RQF_STARTED;
 			trace_block_rq_issue(q, rq);
 		}
 
@@ -2384,7 +2387,7 @@ struct request *blk_peek_request(struct request_queue *q)
 			q->boundary_rq = NULL;
 		}
 
-		if (rq->cmd_flags & REQ_DONTPREP)
+		if (rq->rq_flags & RQF_DONTPREP)
 			break;
 
 		if (q->dma_drain_size && blk_rq_bytes(rq)) {
@@ -2407,11 +2410,11 @@ struct request *blk_peek_request(struct request_queue *q)
 			/*
 			 * the request may have been (partially) prepped.
 			 * we need to keep this request in the front to
-			 * avoid resource deadlock.  REQ_STARTED will
+			 * avoid resource deadlock.  RQF_STARTED will
 			 * prevent other fs requests from passing this one.
 			 */
 			if (q->dma_drain_size && blk_rq_bytes(rq) &&
-			    !(rq->cmd_flags & REQ_DONTPREP)) {
+			    !(rq->rq_flags & RQF_DONTPREP)) {
 				/*
 				 * remove the space for the drain we added
 				 * so that we don't add it again
@@ -2424,7 +2427,7 @@ struct request *blk_peek_request(struct request_queue *q)
 		} else if (ret == BLKPREP_KILL || ret == BLKPREP_INVALID) {
 			int err = (ret == BLKPREP_INVALID) ? -EREMOTEIO : -EIO;
 
-			rq->cmd_flags |= REQ_QUIET;
+			rq->rq_flags |= RQF_QUIET;
 			/*
 			 * Mark this request as started so we don't trigger
 			 * any debug logic in the end I/O path.
@@ -2561,7 +2564,7 @@ bool blk_update_request(struct request *req, int error, unsigned int nr_bytes)
 		req->errors = 0;
 
 	if (error && req->cmd_type == REQ_TYPE_FS &&
-	    !(req->cmd_flags & REQ_QUIET)) {
+	    !(req->rq_flags & RQF_QUIET)) {
 		char *error_type;
 
 		switch (error) {
@@ -2634,7 +2637,7 @@ bool blk_update_request(struct request *req, int error, unsigned int nr_bytes)
 		req->__sector += total_bytes >> 9;
 
 	/* mixed attributes always follow the first bio */
-	if (req->cmd_flags & REQ_MIXED_MERGE) {
+	if (req->rq_flags & RQF_MIXED_MERGE) {
 		req->cmd_flags &= ~REQ_FAILFAST_MASK;
 		req->cmd_flags |= req->bio->bi_opf & REQ_FAILFAST_MASK;
 	}
@@ -2687,7 +2690,7 @@ void blk_unprep_request(struct request *req)
 {
 	struct request_queue *q = req->q;
 
-	req->cmd_flags &= ~REQ_DONTPREP;
+	req->rq_flags &= ~RQF_DONTPREP;
 	if (q->unprep_rq_fn)
 		q->unprep_rq_fn(q, req);
 }
@@ -2698,7 +2701,7 @@ EXPORT_SYMBOL_GPL(blk_unprep_request);
  */
 void blk_finish_request(struct request *req, int error)
 {
-	if (req->cmd_flags & REQ_QUEUED)
+	if (req->rq_flags & RQF_QUEUED)
 		blk_queue_end_tag(req->q, req);
 
 	BUG_ON(blk_queued_rq(req));
@@ -2708,7 +2711,7 @@ void blk_finish_request(struct request *req, int error)
 
 	blk_delete_timer(req);
 
-	if (req->cmd_flags & REQ_DONTPREP)
+	if (req->rq_flags & RQF_DONTPREP)
 		blk_unprep_request(req);
 
 	blk_account_io_done(req);
diff --git a/block/blk-exec.c b/block/blk-exec.c
index 7ea04325d02f..3ecb00a6cf45 100644
--- a/block/blk-exec.c
+++ b/block/blk-exec.c
@@ -72,7 +72,7 @@ void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk,
 	spin_lock_irq(q->queue_lock);
 
 	if (unlikely(blk_queue_dying(q))) {
-		rq->cmd_flags |= REQ_QUIET; 
+		rq->rq_flags |= RQF_QUIET;
 		rq->errors = -ENXIO;
 		__blk_end_request_all(rq, rq->errors);
 		spin_unlock_irq(q->queue_lock);
diff --git a/block/blk-flush.c b/block/blk-flush.c
index 6a14b68b9135..3990b9cfbda5 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -56,7 +56,7 @@
  * Once while executing DATA and again after the whole sequence is
  * complete.  The first completion updates the contained bio but doesn't
  * finish it so that the bio submitter is notified only after the whole
- * sequence is complete.  This is implemented by testing REQ_FLUSH_SEQ in
+ * sequence is complete.  This is implemented by testing RQF_FLUSH_SEQ in
  * req_bio_endio().
  *
  * The above peculiarity requires that each FLUSH/FUA request has only one
@@ -127,7 +127,7 @@ static void blk_flush_restore_request(struct request *rq)
 	rq->bio = rq->biotail;
 
 	/* make @rq a normal request */
-	rq->cmd_flags &= ~REQ_FLUSH_SEQ;
+	rq->rq_flags &= ~RQF_FLUSH_SEQ;
 	rq->end_io = rq->flush.saved_end_io;
 }
 
@@ -330,7 +330,8 @@ static bool blk_kick_flush(struct request_queue *q, struct blk_flush_queue *fq)
 	}
 
 	flush_rq->cmd_type = REQ_TYPE_FS;
-	req_set_op_attrs(flush_rq, REQ_OP_FLUSH, WRITE_FLUSH | REQ_FLUSH_SEQ);
+	req_set_op_attrs(flush_rq, REQ_OP_FLUSH, WRITE_FLUSH);
+	flush_rq->rq_flags |= RQF_FLUSH_SEQ;
 	flush_rq->rq_disk = first_rq->rq_disk;
 	flush_rq->end_io = flush_end_io;
 
@@ -433,7 +434,7 @@ void blk_insert_flush(struct request *rq)
 	 */
 	memset(&rq->flush, 0, sizeof(rq->flush));
 	INIT_LIST_HEAD(&rq->flush.list);
-	rq->cmd_flags |= REQ_FLUSH_SEQ;
+	rq->rq_flags |= RQF_FLUSH_SEQ;
 	rq->flush.saved_end_io = rq->end_io; /* Usually NULL */
 	if (q->mq_ops) {
 		rq->end_io = mq_flush_data_end_io;
diff --git a/block/blk-map.c b/block/blk-map.c
index b8657fa8dc9a..2c5ae5fef473 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -135,7 +135,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
 	} while (iov_iter_count(&i));
 
 	if (!bio_flagged(bio, BIO_USER_MAPPED))
-		rq->cmd_flags |= REQ_COPY_USER;
+		rq->rq_flags |= RQF_COPY_USER;
 	return 0;
 
 unmap_rq:
@@ -232,7 +232,7 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
 		bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
 
 	if (do_copy)
-		rq->cmd_flags |= REQ_COPY_USER;
+		rq->rq_flags |= RQF_COPY_USER;
 
 	ret = blk_rq_append_bio(rq, bio);
 	if (unlikely(ret)) {
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 2642e5fc8b69..fda6a12fc776 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -456,7 +456,7 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq,
 	if (rq->bio)
 		nsegs = __blk_bios_map_sg(q, rq->bio, sglist, &sg);
 
-	if (unlikely(rq->cmd_flags & REQ_COPY_USER) &&
+	if (unlikely(rq->rq_flags & RQF_COPY_USER) &&
 	    (blk_rq_bytes(rq) & q->dma_pad_mask)) {
 		unsigned int pad_len =
 			(q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1;
@@ -634,7 +634,7 @@ void blk_rq_set_mixed_merge(struct request *rq)
 	unsigned int ff = rq->cmd_flags & REQ_FAILFAST_MASK;
 	struct bio *bio;
 
-	if (rq->cmd_flags & REQ_MIXED_MERGE)
+	if (rq->rq_flags & RQF_MIXED_MERGE)
 		return;
 
 	/*
@@ -647,7 +647,7 @@ void blk_rq_set_mixed_merge(struct request *rq)
 			     (bio->bi_opf & REQ_FAILFAST_MASK) != ff);
 		bio->bi_opf |= ff;
 	}
-	rq->cmd_flags |= REQ_MIXED_MERGE;
+	rq->rq_flags |= RQF_MIXED_MERGE;
 }
 
 static void blk_account_io_merge(struct request *req)
@@ -709,7 +709,7 @@ static int attempt_merge(struct request_queue *q, struct request *req,
 	 * makes sure that all involved bios have mixable attributes
 	 * set properly.
 	 */
-	if ((req->cmd_flags | next->cmd_flags) & REQ_MIXED_MERGE ||
+	if (((req->rq_flags | next->rq_flags) & RQF_MIXED_MERGE) ||
 	    (req->cmd_flags & REQ_FAILFAST_MASK) !=
 	    (next->cmd_flags & REQ_FAILFAST_MASK)) {
 		blk_rq_set_mixed_merge(req);
diff --git a/block/blk-mq.c b/block/blk-mq.c
index d74a74a9f9ef..b49c6658eb05 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -142,14 +142,13 @@ static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx,
 			       struct request *rq, int op,
 			       unsigned int op_flags)
 {
-	if (blk_queue_io_stat(q))
-		op_flags |= REQ_IO_STAT;
-
 	INIT_LIST_HEAD(&rq->queuelist);
 	/* csd/requeue_work/fifo_time is initialized before use */
 	rq->q = q;
 	rq->mq_ctx = ctx;
 	req_set_op_attrs(rq, op, op_flags);
+	if (blk_queue_io_stat(q))
+		rq->rq_flags |= RQF_IO_STAT;
 	/* do not touch atomic flags, it needs atomic ops against the timer */
 	rq->cpu = -1;
 	INIT_HLIST_NODE(&rq->hash);
@@ -198,7 +197,7 @@ __blk_mq_alloc_request(struct blk_mq_alloc_data *data, int op, int op_flags)
 		rq = data->hctx->tags->rqs[tag];
 
 		if (blk_mq_tag_busy(data->hctx)) {
-			rq->cmd_flags = REQ_MQ_INFLIGHT;
+			rq->rq_flags = RQF_MQ_INFLIGHT;
 			atomic_inc(&data->hctx->nr_active);
 		}
 
@@ -298,9 +297,9 @@ static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx,
 	const int tag = rq->tag;
 	struct request_queue *q = rq->q;
 
-	if (rq->cmd_flags & REQ_MQ_INFLIGHT)
+	if (rq->rq_flags & RQF_MQ_INFLIGHT)
 		atomic_dec(&hctx->nr_active);
-	rq->cmd_flags = 0;
+	rq->rq_flags = 0;
 
 	clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags);
 	blk_mq_put_tag(hctx, ctx, tag);
@@ -489,10 +488,10 @@ static void blk_mq_requeue_work(struct work_struct *work)
 	spin_unlock_irqrestore(&q->requeue_lock, flags);
 
 	list_for_each_entry_safe(rq, next, &rq_list, queuelist) {
-		if (!(rq->cmd_flags & REQ_SOFTBARRIER))
+		if (!(rq->rq_flags & RQF_SOFTBARRIER))
 			continue;
 
-		rq->cmd_flags &= ~REQ_SOFTBARRIER;
+		rq->rq_flags &= ~RQF_SOFTBARRIER;
 		list_del_init(&rq->queuelist);
 		blk_mq_insert_request(rq, true, false, false);
 	}
@@ -519,11 +518,11 @@ void blk_mq_add_to_requeue_list(struct request *rq, bool at_head)
 	 * We abuse this flag that is otherwise used by the I/O scheduler to
 	 * request head insertation from the workqueue.
 	 */
-	BUG_ON(rq->cmd_flags & REQ_SOFTBARRIER);
+	BUG_ON(rq->rq_flags & RQF_SOFTBARRIER);
 
 	spin_lock_irqsave(&q->requeue_lock, flags);
 	if (at_head) {
-		rq->cmd_flags |= REQ_SOFTBARRIER;
+		rq->rq_flags |= RQF_SOFTBARRIER;
 		list_add(&rq->queuelist, &q->requeue_list);
 	} else {
 		list_add_tail(&rq->queuelist, &q->requeue_list);
diff --git a/block/blk-tag.c b/block/blk-tag.c
index f0344e6939d5..bae1decb6ec3 100644
--- a/block/blk-tag.c
+++ b/block/blk-tag.c
@@ -270,7 +270,7 @@ void blk_queue_end_tag(struct request_queue *q, struct request *rq)
 	BUG_ON(tag >= bqt->real_max_depth);
 
 	list_del_init(&rq->queuelist);
-	rq->cmd_flags &= ~REQ_QUEUED;
+	rq->rq_flags &= ~RQF_QUEUED;
 	rq->tag = -1;
 
 	if (unlikely(bqt->tag_index[tag] == NULL))
@@ -316,7 +316,7 @@ int blk_queue_start_tag(struct request_queue *q, struct request *rq)
 	unsigned max_depth;
 	int tag;
 
-	if (unlikely((rq->cmd_flags & REQ_QUEUED))) {
+	if (unlikely((rq->rq_flags & RQF_QUEUED))) {
 		printk(KERN_ERR
 		       "%s: request %p for device [%s] already tagged %d",
 		       __func__, rq,
@@ -371,7 +371,7 @@ int blk_queue_start_tag(struct request_queue *q, struct request *rq)
 	 */
 
 	bqt->next_tag = (tag + 1) % bqt->max_depth;
-	rq->cmd_flags |= REQ_QUEUED;
+	rq->rq_flags |= RQF_QUEUED;
 	rq->tag = tag;
 	bqt->tag_index[tag] = rq;
 	blk_start_request(rq);
diff --git a/block/blk.h b/block/blk.h
index 74444c49078f..aa132dea598c 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -130,7 +130,7 @@ static inline void blk_clear_rq_complete(struct request *rq)
 /*
  * Internal elevator interface
  */
-#define ELV_ON_HASH(rq) ((rq)->cmd_flags & REQ_HASHED)
+#define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
 
 void blk_insert_flush(struct request *rq);
 
@@ -247,7 +247,7 @@ extern int blk_update_nr_requests(struct request_queue *, unsigned int);
 static inline int blk_do_io_stat(struct request *rq)
 {
 	return rq->rq_disk &&
-	       (rq->cmd_flags & REQ_IO_STAT) &&
+	       (rq->rq_flags & RQF_IO_STAT) &&
 		(rq->cmd_type == REQ_TYPE_FS);
 }
 
diff --git a/block/elevator.c b/block/elevator.c
index f7d973a56fd7..ac80f89a0842 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -245,7 +245,7 @@ EXPORT_SYMBOL(elevator_exit);
 static inline void __elv_rqhash_del(struct request *rq)
 {
 	hash_del(&rq->hash);
-	rq->cmd_flags &= ~REQ_HASHED;
+	rq->rq_flags &= ~RQF_HASHED;
 }
 
 static void elv_rqhash_del(struct request_queue *q, struct request *rq)
@@ -260,7 +260,7 @@ static void elv_rqhash_add(struct request_queue *q, struct request *rq)
 
 	BUG_ON(ELV_ON_HASH(rq));
 	hash_add(e->hash, &rq->hash, rq_hash_key(rq));
-	rq->cmd_flags |= REQ_HASHED;
+	rq->rq_flags |= RQF_HASHED;
 }
 
 static void elv_rqhash_reposition(struct request_queue *q, struct request *rq)
@@ -352,7 +352,6 @@ void elv_dispatch_sort(struct request_queue *q, struct request *rq)
 {
 	sector_t boundary;
 	struct list_head *entry;
-	int stop_flags;
 
 	if (q->last_merge == rq)
 		q->last_merge = NULL;
@@ -362,7 +361,6 @@ void elv_dispatch_sort(struct request_queue *q, struct request *rq)
 	q->nr_sorted--;
 
 	boundary = q->end_sector;
-	stop_flags = REQ_SOFTBARRIER | REQ_STARTED;
 	list_for_each_prev(entry, &q->queue_head) {
 		struct request *pos = list_entry_rq(entry);
 
@@ -370,7 +368,7 @@ void elv_dispatch_sort(struct request_queue *q, struct request *rq)
 			break;
 		if (rq_data_dir(rq) != rq_data_dir(pos))
 			break;
-		if (pos->cmd_flags & stop_flags)
+		if (pos->rq_flags & (RQF_STARTED | RQF_SOFTBARRIER))
 			break;
 		if (blk_rq_pos(rq) >= boundary) {
 			if (blk_rq_pos(pos) < boundary)
@@ -510,7 +508,7 @@ void elv_merge_requests(struct request_queue *q, struct request *rq,
 			     struct request *next)
 {
 	struct elevator_queue *e = q->elevator;
-	const int next_sorted = next->cmd_flags & REQ_SORTED;
+	const int next_sorted = next->rq_flags & RQF_SORTED;
 
 	if (next_sorted && e->type->ops.elevator_merge_req_fn)
 		e->type->ops.elevator_merge_req_fn(q, rq, next);
@@ -537,13 +535,13 @@ void elv_bio_merged(struct request_queue *q, struct request *rq,
 #ifdef CONFIG_PM
 static void blk_pm_requeue_request(struct request *rq)
 {
-	if (rq->q->dev && !(rq->cmd_flags & REQ_PM))
+	if (rq->q->dev && !(rq->rq_flags & RQF_PM))
 		rq->q->nr_pending--;
 }
 
 static void blk_pm_add_request(struct request_queue *q, struct request *rq)
 {
-	if (q->dev && !(rq->cmd_flags & REQ_PM) && q->nr_pending++ == 0 &&
+	if (q->dev && !(rq->rq_flags & RQF_PM) && q->nr_pending++ == 0 &&
 	    (q->rpm_status == RPM_SUSPENDED || q->rpm_status == RPM_SUSPENDING))
 		pm_request_resume(q->dev);
 }
@@ -563,11 +561,11 @@ void elv_requeue_request(struct request_queue *q, struct request *rq)
 	 */
 	if (blk_account_rq(rq)) {
 		q->in_flight[rq_is_sync(rq)]--;
-		if (rq->cmd_flags & REQ_SORTED)
+		if (rq->rq_flags & RQF_SORTED)
 			elv_deactivate_rq(q, rq);
 	}
 
-	rq->cmd_flags &= ~REQ_STARTED;
+	rq->rq_flags &= ~RQF_STARTED;
 
 	blk_pm_requeue_request(rq);
 
@@ -597,13 +595,13 @@ void __elv_add_request(struct request_queue *q, struct request *rq, int where)
 
 	rq->q = q;
 
-	if (rq->cmd_flags & REQ_SOFTBARRIER) {
+	if (rq->rq_flags & RQF_SOFTBARRIER) {
 		/* barriers are scheduling boundary, update end_sector */
 		if (rq->cmd_type == REQ_TYPE_FS) {
 			q->end_sector = rq_end_sector(rq);
 			q->boundary_rq = rq;
 		}
-	} else if (!(rq->cmd_flags & REQ_ELVPRIV) &&
+	} else if (!(rq->rq_flags & RQF_ELVPRIV) &&
 		    (where == ELEVATOR_INSERT_SORT ||
 		     where == ELEVATOR_INSERT_SORT_MERGE))
 		where = ELEVATOR_INSERT_BACK;
@@ -611,12 +609,12 @@ void __elv_add_request(struct request_queue *q, struct request *rq, int where)
 	switch (where) {
 	case ELEVATOR_INSERT_REQUEUE:
 	case ELEVATOR_INSERT_FRONT:
-		rq->cmd_flags |= REQ_SOFTBARRIER;
+		rq->rq_flags |= RQF_SOFTBARRIER;
 		list_add(&rq->queuelist, &q->queue_head);
 		break;
 
 	case ELEVATOR_INSERT_BACK:
-		rq->cmd_flags |= REQ_SOFTBARRIER;
+		rq->rq_flags |= RQF_SOFTBARRIER;
 		elv_drain_elevator(q);
 		list_add_tail(&rq->queuelist, &q->queue_head);
 		/*
@@ -642,7 +640,7 @@ void __elv_add_request(struct request_queue *q, struct request *rq, int where)
 			break;
 	case ELEVATOR_INSERT_SORT:
 		BUG_ON(rq->cmd_type != REQ_TYPE_FS);
-		rq->cmd_flags |= REQ_SORTED;
+		rq->rq_flags |= RQF_SORTED;
 		q->nr_sorted++;
 		if (rq_mergeable(rq)) {
 			elv_rqhash_add(q, rq);
@@ -659,7 +657,7 @@ void __elv_add_request(struct request_queue *q, struct request *rq, int where)
 		break;
 
 	case ELEVATOR_INSERT_FLUSH:
-		rq->cmd_flags |= REQ_SOFTBARRIER;
+		rq->rq_flags |= RQF_SOFTBARRIER;
 		blk_insert_flush(rq);
 		break;
 	default:
@@ -735,7 +733,7 @@ void elv_completed_request(struct request_queue *q, struct request *rq)
 	 */
 	if (blk_account_rq(rq)) {
 		q->in_flight[rq_is_sync(rq)]--;
-		if ((rq->cmd_flags & REQ_SORTED) &&
+		if ((rq->rq_flags & RQF_SORTED) &&
 		    e->type->ops.elevator_completed_req_fn)
 			e->type->ops.elevator_completed_req_fn(q, rq);
 	}