[PATCH 5.18 465/879] nvme: set dma alignment to dword

Greg Kroah-Hartman
2022-06-08T00:47:30Z

From: Keith Busch <kbusch@kernel.org>

[ Upstream commit 52fde2c07da606f3f120af4f734eadcfb52b04be ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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 ac32d1cd8477..2d6a01853109 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1771,7 +1771,7 @@ static void nvme_set_queue_limits(struct nvme_ctrl *ctrl,
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);
}

--
2.35.1