From: Ming Lei <ming.lei@xxxxxxxxxx>
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>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
---
block/blk-core.c | 12 +++++++++---
block/genhd.c | 2 ++
include/linux/blkdev.h | 2 ++
3 files changed, 13 insertions(+), 3 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index 94bf37f8e61d..e739c6264331 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -985,10 +985,16 @@ int bio_poll(struct bio *bio, struct io_comp_batch *iob, 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)) {
ret = blk_mq_poll(q, cookie, iob, flags);
+ } else {
+ struct gendisk *disk = q->disk;
+
+ if (disk && disk->fops->poll_bio)
+ ret = disk->fops->poll_bio(bio, iob, flags);
+ else
+ ret = !WARN_ON_ONCE(1);
+ }
blk_queue_exit(q);
return ret;
}
diff --git a/block/genhd.c b/block/genhd.c
index e351fac41bf2..eb43fa63ba47 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -410,6 +410,8 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk,
struct device *ddev = disk_to_dev(disk);
int ret;
+ 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 f757f9c2871f..51f1b1ddbed2 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1455,6 +1455,8 @@ enum blk_unique_id {
struct block_device_operations {
void (*submit_bio)(struct bio *bio);
+ int (*poll_bio)(struct bio *bio, struct io_comp_batch *iob,
+ 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);
--
2.15.0
--
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