diff mbox series

[13/15] block: add a QUEUE_FLAG_POLL_CAPABLE flag

Message ID 20210427161619.1294399-14-hch@lst.de (mailing list archive)
State New, archived
Headers show
Series [01/15] direct-io: remove blk_poll support | expand

Commit Message

Christoph Hellwig April 27, 2021, 4:16 p.m. UTC 
Add a new flag to prepare for bio based stacking drivers that support
polling.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 block/blk-mq.c         | 4 +++-
 block/blk-sysfs.c      | 3 +--
 include/linux/blkdev.h | 1 +
 3 files changed, 5 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/block/blk-mq.c b/block/blk-mq.c
index c26df1f68e5b..45e69eea2788 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -3236,8 +3236,10 @@  struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
 
 	q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT;
 	if (set->nr_maps > HCTX_TYPE_POLL &&
-	    set->map[HCTX_TYPE_POLL].nr_queues)
+	    set->map[HCTX_TYPE_POLL].nr_queues) {
+		blk_queue_flag_set(QUEUE_FLAG_POLL_CAPABLE, q);
 		blk_queue_flag_set(QUEUE_FLAG_POLL, q);
+	}
 
 	q->sg_reserved_size = INT_MAX;
 
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index e03bedf180ab..258468a3ab9c 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -431,8 +431,7 @@  static ssize_t queue_poll_store(struct request_queue *q, const char *page,
 	unsigned long poll_on;
 	ssize_t ret;
 
-	if (!q->tag_set || q->tag_set->nr_maps <= HCTX_TYPE_POLL ||
-	    !q->tag_set->map[HCTX_TYPE_POLL].nr_queues)
+	if (!test_bit(QUEUE_FLAG_POLL_CAPABLE, &q->queue_flags))
 		return -EINVAL;
 
 	ret = queue_var_store(&poll_on, page, count);
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index bb5ed5cf57b4..366cf2a6d2e8 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -600,6 +600,7 @@  struct request_queue {
 /* Keep blk_queue_flag_name[] in sync with the definitions below */
 #define QUEUE_FLAG_STOPPED	0	/* queue is stopped */
 #define QUEUE_FLAG_DYING	1	/* queue being torn down */
+#define QUEUE_FLAG_POLL_CAPABLE	2	/* IO polling supported */
 #define QUEUE_FLAG_NOMERGES     3	/* disable merge attempts */
 #define QUEUE_FLAG_SAME_COMP	4	/* complete on same CPU-group */
 #define QUEUE_FLAG_FAIL_IO	5	/* fake timeout */