Enable iopoll when all underlying target devices supports iopoll. Signed-off-by: Jeffle Xu <jefflexu@xxxxxxxxxxxxxxxxx> --- drivers/md/dm-table.c | 28 ++++++++++++++++++++++++++++ drivers/md/dm.c | 1 + 2 files changed, 29 insertions(+) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 188f41287f18..b0cd5bf58c3c 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -1791,6 +1791,31 @@ static bool dm_table_requires_stable_pages(struct dm_table *t) return false; } +static int device_supports_poll(struct dm_target *ti, struct dm_dev *dev, + sector_t start, sector_t len, void *data) +{ + struct request_queue *q = bdev_get_queue(dev->bdev); + + return q && test_bit(QUEUE_FLAG_POLL, &q->queue_flags); +} + +static bool dm_table_supports_poll(struct dm_table *t) +{ + struct dm_target *ti; + unsigned int i; + + /* Ensure that all targets support iopoll. */ + for (i = 0; i < dm_table_get_num_targets(t); i++) { + ti = dm_table_get_target(t, i); + + if (!ti->type->iterate_devices || + !ti->type->iterate_devices(ti, device_supports_poll, NULL)) + return false; + } + + return true; +} + void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, struct queue_limits *limits) { @@ -1883,6 +1908,9 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, #endif blk_queue_update_readahead(q); + + if (dm_table_supports_poll(t)) + blk_queue_flag_set(QUEUE_FLAG_POLL, q); } unsigned int dm_table_get_num_targets(struct dm_table *t) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 03c2b867acaa..ffd2c5ead256 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -3049,6 +3049,7 @@ static const struct pr_ops dm_pr_ops = { }; static const struct block_device_operations dm_blk_dops = { + .iopoll = blk_bio_poll, .submit_bio = dm_submit_bio, .open = dm_blk_open, .release = dm_blk_close, -- 2.27.0