Prepare for supporting IO polling for bio based driver.
Add ->poll_bio callback so that bio driver can provide their own logic
for polling bio.
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
block/blk-core.c | 18 +++++++++++++-----
block/genhd.c | 3 +++
include/linux/blkdev.h | 2 ++
3 files changed, 18 insertions(+), 5 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index 1e24c71c6738..a1552ec8d608 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1113,11 +1113,13 @@ EXPORT_SYMBOL(submit_bio);
*/
int bio_poll(struct bio *bio, unsigned int flags)
{
- struct request_queue *q = bio->bi_bdev->bd_disk->queue;
+ struct gendisk *disk = bio->bi_bdev->bd_disk;
+ struct request_queue *q = disk->queue;
blk_qc_t cookie = READ_ONCE(bio->bi_cookie);
int ret;
- if (cookie == BLK_QC_T_NONE || !blk_queue_poll(q))
+ if ((queue_is_mq(q) && cookie == BLK_QC_T_NONE) ||
+ !blk_queue_poll(q))
return 0;
if (current->plug)
@@ -1125,10 +1127,16 @@ int bio_poll(struct bio *bio, unsigned int flags)
if (blk_queue_enter(q, BLK_MQ_REQ_NOWAIT))
return 0;
- if (WARN_ON_ONCE(!queue_is_mq(q)))
- ret = 0; /* not yet implemented, should not happen */
- else
+ if (!queue_is_mq(q)) {
+ if (disk->fops->poll_bio) {
+ ret = disk->fops->poll_bio(bio, flags);
+ } else {
+ WARN_ON_ONCE(1);
+ ret = 0;
+ }
+ } else {
ret = blk_mq_poll(q, cookie, flags);
+ }
blk_queue_exit(q);
return ret;
}
diff --git a/block/genhd.c b/block/genhd.c
index 5f5628216295..042dfa5b3f79 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -471,6 +471,9 @@ static void __device_add_disk(struct device *parent, struct gendisk *disk,
{
int ret;
+ /* ->poll_bio is only for bio based driver */
+ WARN_ON_ONCE(queue_is_mq(disk->queue) && disk->fops->poll_bio);
+
/*
* The disk queue should now be all set with enough information about
* the device for the elevator code to pick an adequate default
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index fc0ba0b80776..6da6fb120148 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1858,6 +1858,8 @@ static inline void blk_ksm_unregister(struct request_queue *q) { }
struct block_device_operations {
void (*submit_bio)(struct bio *bio);
+ /* ->poll_bio is for bio driver only */
+ int (*poll_bio)(struct bio *bio, unsigned int flags);
int (*open) (struct block_device *, fmode_t);
void (*release) (struct gendisk *, fmode_t);
int (*rw_page)(struct block_device *, sector_t, struct page *, unsigned int);
--
2.31.1
--
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