From 998e9cbcd615e5e6a7baa69e673ee845f812744e Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 15 Apr 2022 06:52:38 +0200 Subject: [PATCH] drbd: cleanup decide_on_discard_support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sanitize the calling conventions and use a goto label to cleanup the code flow. Signed-off-by: Christoph Hellwig Acked-by: Christoph Böhmwalder Link: https://lore.kernel.org/r/20220415045258.199825-8-hch@lst.de Signed-off-by: Jens Axboe --- drivers/block/drbd/drbd_nl.c | 66 +++++++++++++++++++----------------- 1 file changed, 34 insertions(+), 32 deletions(-) diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index b7216c186ba4..4d00986d6f58 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -1204,38 +1204,42 @@ static unsigned int drbd_max_discard_sectors(struct drbd_connection *connection) } static void decide_on_discard_support(struct drbd_device *device, - struct request_queue *q, - struct request_queue *b, - bool discard_zeroes_if_aligned) + struct drbd_backing_dev *bdev) { - /* q = drbd device queue (device->rq_queue) - * b = backing device queue (device->ldev->backing_bdev->bd_disk->queue), - * or NULL if diskless - */ - struct drbd_connection *connection = first_peer_device(device)->connection; - bool can_do = b ? blk_queue_discard(b) : true; + struct drbd_connection *connection = + first_peer_device(device)->connection; + struct request_queue *q = device->rq_queue; - if (can_do && connection->cstate >= C_CONNECTED && !(connection->agreed_features & DRBD_FF_TRIM)) { - can_do = false; - drbd_info(connection, "peer DRBD too old, does not support TRIM: disabling discards\n"); - } - if (can_do) { - /* We don't care for the granularity, really. - * Stacking limits below should fix it for the local - * device. Whether or not it is a suitable granularity - * on the remote device is not our problem, really. If - * you care, you need to use devices with similar - * topology on all peers. */ - blk_queue_discard_granularity(q, 512); - q->limits.max_discard_sectors = drbd_max_discard_sectors(connection); - blk_queue_flag_set(QUEUE_FLAG_DISCARD, q); - q->limits.max_write_zeroes_sectors = drbd_max_discard_sectors(connection); - } else { - blk_queue_flag_clear(QUEUE_FLAG_DISCARD, q); - blk_queue_discard_granularity(q, 0); - q->limits.max_discard_sectors = 0; - q->limits.max_write_zeroes_sectors = 0; + if (bdev && !blk_queue_discard(bdev->backing_bdev->bd_disk->queue)) + goto not_supported; + + if (connection->cstate >= C_CONNECTED && + !(connection->agreed_features & DRBD_FF_TRIM)) { + drbd_info(connection, + "peer DRBD too old, does not support TRIM: disabling discards\n"); + goto not_supported; } + + /* + * We don't care for the granularity, really. + * + * Stacking limits below should fix it for the local device. Whether or + * not it is a suitable granularity on the remote device is not our + * problem, really. If you care, you need to use devices with similar + * topology on all peers. + */ + blk_queue_discard_granularity(q, 512); + q->limits.max_discard_sectors = drbd_max_discard_sectors(connection); + blk_queue_flag_set(QUEUE_FLAG_DISCARD, q); + q->limits.max_write_zeroes_sectors = + drbd_max_discard_sectors(connection); + return; + +not_supported: + blk_queue_flag_clear(QUEUE_FLAG_DISCARD, q); + blk_queue_discard_granularity(q, 0); + q->limits.max_discard_sectors = 0; + q->limits.max_write_zeroes_sectors = 0; } static void fixup_discard_if_not_supported(struct request_queue *q) @@ -1273,7 +1277,6 @@ static void drbd_setup_queue_param(struct drbd_device *device, struct drbd_backi unsigned int max_segments = 0; struct request_queue *b = NULL; struct disk_conf *dc; - bool discard_zeroes_if_aligned = true; if (bdev) { b = bdev->backing_bdev->bd_disk->queue; @@ -1282,7 +1285,6 @@ static void drbd_setup_queue_param(struct drbd_device *device, struct drbd_backi rcu_read_lock(); dc = rcu_dereference(device->ldev->disk_conf); max_segments = dc->max_bio_bvecs; - discard_zeroes_if_aligned = dc->discard_zeroes_if_aligned; rcu_read_unlock(); blk_set_stacking_limits(&q->limits); @@ -1292,7 +1294,7 @@ static void drbd_setup_queue_param(struct drbd_device *device, struct drbd_backi /* This is the workaround for "bio would need to, but cannot, be split" */ 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_discard_support(device, bdev); if (b) { blk_stack_limits(&q->limits, &b->limits, 0);