From: Konstantin Khlebnikov <[email protected]> Add DM target feature flag DM_TARGET_NOWAIT which advertises that target works with REQ_NOWAIT bios.
Add dm_table_supports_nowait() and update dm_table_set_restrictions() to set/clear QUEUE_FLAG_NOWAIT accordingly. Signed-off-by: Konstantin Khlebnikov <[email protected]> Signed-off-by: Mike Snitzer <[email protected]> --- drivers/md/dm-linear.c | 5 +++-- drivers/md/dm-table.c | 32 ++++++++++++++++++++++++++++++++ drivers/md/dm.c | 4 +++- include/linux/device-mapper.h | 6 ++++++ 4 files changed, 44 insertions(+), 3 deletions(-) diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c index e1db43446327..00774b5d7668 100644 --- a/drivers/md/dm-linear.c +++ b/drivers/md/dm-linear.c @@ -228,10 +228,11 @@ static struct target_type linear_target = { .name = "linear", .version = {1, 4, 0}, #ifdef CONFIG_BLK_DEV_ZONED - .features = DM_TARGET_PASSES_INTEGRITY | DM_TARGET_ZONED_HM, + .features = DM_TARGET_PASSES_INTEGRITY | DM_TARGET_NOWAIT | + DM_TARGET_ZONED_HM, .report_zones = linear_report_zones, #else - .features = DM_TARGET_PASSES_INTEGRITY, + .features = DM_TARGET_PASSES_INTEGRITY | DM_TARGET_NOWAIT, #endif .module = THIS_MODULE, .ctr = linear_ctr, diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index acba92500c12..17fb9b96d18e 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -1719,6 +1719,33 @@ static bool dm_table_supports_write_zeroes(struct dm_table *t) return true; } +static int device_not_nowait_capable(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 && !blk_queue_nowait(q); +} + +static bool dm_table_supports_nowait(struct dm_table *t) +{ + struct dm_target *ti; + unsigned i = 0; + + while (i < dm_table_get_num_targets(t)) { + ti = dm_table_get_target(t, i++); + + if (!dm_target_supports_nowait(ti->type)) + return false; + + if (!ti->type->iterate_devices || + ti->type->iterate_devices(ti, device_not_nowait_capable, NULL)) + return false; + } + + return true; +} + static int device_not_discard_capable(struct dm_target *ti, struct dm_dev *dev, sector_t start, sector_t len, void *data) { @@ -1821,6 +1848,11 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, */ q->limits = *limits; + if (dm_table_supports_nowait(t)) + blk_queue_flag_set(QUEUE_FLAG_NOWAIT, q); + else + blk_queue_flag_clear(QUEUE_FLAG_NOWAIT, q); + if (!dm_table_supports_discards(t)) { blk_queue_flag_clear(QUEUE_FLAG_DISCARD, q); /* Must also clear discard limits... */ diff --git a/drivers/md/dm.c b/drivers/md/dm.c index b110b5eb99a5..3ad4a8da8b15 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1733,7 +1733,9 @@ static blk_qc_t dm_submit_bio(struct bio *bio) if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) { dm_put_live_table(md, srcu_idx); - if (!(bio->bi_opf & REQ_RAHEAD)) + if (bio->bi_opf & REQ_NOWAIT) + bio_wouldblock_error(bio); + else if (!(bio->bi_opf & REQ_RAHEAD)) queue_io(md, bio); else bio_io_error(bio); diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index 57610fc3013e..ba3b0979e09f 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -252,6 +252,12 @@ struct target_type { #define DM_TARGET_ZONED_HM 0x00000040 #define dm_target_supports_zoned_hm(type) ((type)->features & DM_TARGET_ZONED_HM) +/* + * A target handles REQ_NOWAIT + */ +#define DM_TARGET_NOWAIT 0x00000080 +#define dm_target_supports_nowait(type) ((type)->features & DM_TARGET_NOWAIT) + struct dm_target { struct dm_table *table; struct target_type *type; -- 2.15.0 -- dm-devel mailing list [email protected] https://www.redhat.com/mailman/listinfo/dm-devel
