From mboxrd@z Thu Jan 1 00:00:00 1970 From: ddiss@suse.de (David Disseldorp) Date: Fri, 24 Nov 2017 16:30:53 +0100 Subject: [PATCH] nvme: set discard_alignment to zero Message-ID: <20171124153053.23056-1-ddiss@suse.de> Similar to 7c084289795b ("rbd: set discard_alignment to zero"), NVMe devices are currently incorrectly initialised with the block queue discard_alignment set to the NVMe stream alignment. As per Documentation/ABI/testing/sysfs-block: The discard_alignment parameter indicates how many bytes the beginning of the device is offset from the internal allocation unit's natural alignment. Correcting the discard_alignment parameter to zero has no effect on how discard requests are propagated through the block layer - @alignment in __blkdev_issue_discard() remains zero. However, it does fix other consumers, such as LIO's Block Limits VPD response. Signed-off-by: David Disseldorp --- drivers/nvme/host/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 25da74d310d1..2e224ab5c340 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -1287,7 +1287,7 @@ static void nvme_config_discard(struct nvme_ctrl *ctrl, BUILD_BUG_ON(PAGE_SIZE / sizeof(struct nvme_dsm_range) < NVME_DSM_MAX_RANGES); - queue->limits.discard_alignment = size; + queue->limits.discard_alignment = 0; queue->limits.discard_granularity = size; blk_queue_max_discard_sectors(queue, UINT_MAX); -- 2.13.6