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From: Keith Busch <kbusch@kernel.org>
Date: Wed, 4 May 2022 11:43:25 -0700
Subject: nvme: set dma alignment to dword
Patch-mainline: v5.19-rc1
Git-commit: 52fde2c07da606f3f120af4f734eadcfb52b04be
References: jsc#PED-1183

The nvme specification only requires qword alignment for segment
descriptors, and the driver already guarantees that. The spec has always
allowed user data to be dword aligned, which is what the queue's
attribute is for, so relax the alignment requirement to that value.

While we could allow byte alignment for some controllers when using
SGLs, we still need to support PRP, and that only allows dword.

Fixes: 3b2a1ebceba3 ("nvme: set dma alignment to qword")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Daniel Wagner <dwagner@suse.de>
---
 drivers/nvme/host/core.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1774,7 +1774,7 @@ static void nvme_set_queue_limits(struct
 		blk_queue_max_segments(q, min_t(u32, max_segments, USHRT_MAX));
 	}
 	blk_queue_virt_boundary(q, NVME_CTRL_PAGE_SIZE - 1);
-	blk_queue_dma_alignment(q, 7);
+	blk_queue_dma_alignment(q, 3);
 	blk_queue_write_cache(q, vwc, vwc);
 }