diff options
| -rw-r--r-- | block/blk-zoned.c | 39 |
1 files changed, 31 insertions, 8 deletions
diff --git a/block/blk-zoned.c b/block/blk-zoned.c index 2f61ba56dad2..1e5f362f0409 100644 --- a/block/blk-zoned.c +++ b/block/blk-zoned.c @@ -520,10 +520,28 @@ static inline void disk_put_zone_wplug(struct blk_zone_wplug *zwplug) static inline bool disk_should_remove_zone_wplug(struct gendisk *disk, struct blk_zone_wplug *zwplug) { - /* If the zone is still busy, the plug cannot be removed. */ + /* If the zone write plug was already removed, we are done. */ + if (zwplug->flags & BLK_ZONE_WPLUG_UNHASHED) + return false; + + /* If the zone write plug is still busy, it cannot be removed. */ if (zwplug->flags & BLK_ZONE_WPLUG_BUSY) return false; + /* + * Completions of BIOs with blk_zone_write_plug_bio_endio() may + * happen after handling a request completion with + * blk_zone_write_plug_complete_request() (e.g. with split BIOs + * that are chained). In such case, disk_zone_wplug_unplug_bio() + * should not attempt to remove the zone write plug until all BIO + * completions are seen. Check by looking at the zone write plug + * reference count, which is 2 when the plug is unused (one reference + * taken when the plug was allocated and another reference taken by the + * caller context). + */ + if (atomic_read(&zwplug->ref) > 2) + return false; + /* We can remove zone write plugs for zones that are empty or full. */ return !zwplug->wp_offset || zwplug->wp_offset >= disk->zone_capacity; } @@ -893,8 +911,9 @@ void blk_zone_write_plug_attempt_merge(struct request *req) struct bio *bio; /* - * Completion of this request needs to be handled with - * blk_zone_write_plug_complete_request(). + * Indicate that completion of this request needs to be handled with + * blk_zone_write_plug_complete_request(), which will drop the reference + * on the zone write plug we took above on entry to this function. */ req->rq_flags |= RQF_ZONE_WRITE_PLUGGING; @@ -1223,6 +1242,9 @@ void blk_zone_write_plug_bio_endio(struct bio *bio) spin_unlock_irqrestore(&zwplug->lock, flags); } + /* Drop the reference we took when the BIO was issued. */ + disk_put_zone_wplug(zwplug); + /* * For BIO-based devices, blk_zone_write_plug_complete_request() * is not called. So we need to schedule execution of the next @@ -1231,8 +1253,7 @@ void blk_zone_write_plug_bio_endio(struct bio *bio) if (bio->bi_bdev->bd_has_submit_bio) disk_zone_wplug_unplug_bio(disk, zwplug); - /* Drop the reference we took when the BIO was issued. */ - atomic_dec(&zwplug->ref); + /* Drop the reference we took when entering this function. */ disk_put_zone_wplug(zwplug); } @@ -1246,13 +1267,15 @@ void blk_zone_write_plug_complete_request(struct request *req) req->rq_flags &= ~RQF_ZONE_WRITE_PLUGGING; - disk_zone_wplug_unplug_bio(disk, zwplug); - /* * Drop the reference we took when the request was initialized in * blk_zone_write_plug_attempt_merge(). */ - atomic_dec(&zwplug->ref); + disk_put_zone_wplug(zwplug); + + disk_zone_wplug_unplug_bio(disk, zwplug); + + /* Drop the reference we took when entering this function. */ disk_put_zone_wplug(zwplug); } |