From 9de7e14a1a9c6bc4f9be6ccd9b951341a80dbd52 Mon Sep 17 00:00:00 2001 From: Lars Ellenberg Date: Tue, 29 Aug 2017 10:20:38 +0200 Subject: drbd: new disk-option disable-write-same Some backend devices claim to support write-same, but would fail actual write-same requests. Allow to set (or toggle) whether or not DRBD tries to support write-same. Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe --- drivers/block/drbd/drbd_nl.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) (limited to 'drivers/block/drbd') diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index ad0fcb43e45c..c383b6cf272a 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -1236,12 +1236,18 @@ static void fixup_discard_if_not_supported(struct request_queue *q) static void decide_on_write_same_support(struct drbd_device *device, struct request_queue *q, - struct request_queue *b, struct o_qlim *o) + struct request_queue *b, struct o_qlim *o, + bool disable_write_same) { struct drbd_peer_device *peer_device = first_peer_device(device); struct drbd_connection *connection = peer_device->connection; bool can_do = b ? b->limits.max_write_same_sectors : true; + if (can_do && disable_write_same) { + can_do = false; + drbd_info(peer_device, "WRITE_SAME disabled by config\n"); + } + if (can_do && connection->cstate >= C_CONNECTED && !(connection->agreed_features & DRBD_FF_WSAME)) { can_do = false; drbd_info(peer_device, "peer does not support WRITE_SAME\n"); @@ -1302,6 +1308,7 @@ static void drbd_setup_queue_param(struct drbd_device *device, struct drbd_backi struct request_queue *b = NULL; struct disk_conf *dc; bool discard_zeroes_if_aligned = true; + bool disable_write_same = false; if (bdev) { b = bdev->backing_bdev->bd_disk->queue; @@ -1311,6 +1318,7 @@ static void drbd_setup_queue_param(struct drbd_device *device, struct drbd_backi dc = rcu_dereference(device->ldev->disk_conf); max_segments = dc->max_bio_bvecs; discard_zeroes_if_aligned = dc->discard_zeroes_if_aligned; + disable_write_same = dc->disable_write_same; rcu_read_unlock(); blk_set_stacking_limits(&q->limits); @@ -1321,7 +1329,7 @@ static void drbd_setup_queue_param(struct drbd_device *device, struct drbd_backi blk_queue_max_segments(q, max_segments ? max_segments : BLK_MAX_SEGMENTS); blk_queue_segment_boundary(q, PAGE_SIZE-1); decide_on_discard_support(device, q, b, discard_zeroes_if_aligned); - decide_on_write_same_support(device, q, b, o); + decide_on_write_same_support(device, q, b, o, disable_write_same); if (b) { blk_queue_stack_limits(q, b); @@ -1612,7 +1620,8 @@ int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info) if (write_ordering_changed(old_disk_conf, new_disk_conf)) drbd_bump_write_ordering(device->resource, NULL, WO_BDEV_FLUSH); - if (old_disk_conf->discard_zeroes_if_aligned != new_disk_conf->discard_zeroes_if_aligned) + if (old_disk_conf->discard_zeroes_if_aligned != new_disk_conf->discard_zeroes_if_aligned + || old_disk_conf->disable_write_same != new_disk_conf->disable_write_same) drbd_reconsider_queue_parameters(device, device->ldev, NULL); drbd_md_sync(device); -- cgit v1.2.3