[linux-yocto] [PATCH v5.2] nvme-pci: Set the prp2 correctly when using more than 4k page

[Kevin Hao]

commit a4f40484e7f1dff56bb9f286cc59ffa36e0259eb from
git://git.infradead.org/nvme.git

In the current code, the nvme is using a fixed 4k PRP entry size,
but if the kernel use a page size which is more than 4k, we should
consider the situation that the bv_offset may be larger than the
dev->ctrl.page_size. Otherwise we may miss setting the prp2 and then
cause the command can't be executed correctly.

Fixes: dff824b2aadb ("nvme-pci: optimize mapping of small single segment requests")
Cc: stable at vger.kernel.org
Reviewed-by: Christoph Hellwig <hch at lst.de>
Signed-off-by: Kevin Hao <haokexin at gmail.com>
Signed-off-by: Keith Busch <kbusch at kernel.org>
---
Hi Bruce,

This patch has already been merged into nvme-5.4 and I also CCed stable at vger.kernel.org,
so in theory it could propagate to linux-yocto via the stable update.
But this issue cause a critical malfunction for the nvme interface and
block our validation for it. So I would like to pick this patch ASAP.
We should merge this into v5.2/standard/base branch.

 drivers/nvme/host/pci.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 4b181969c432..869f462e6b6e 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -773,7 +773,8 @@ static blk_status_t nvme_setup_prp_simple(struct nvme_dev *dev,
 		struct bio_vec *bv)
 {
 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
-	unsigned int first_prp_len = dev->ctrl.page_size - bv->bv_offset;
+	unsigned int offset = bv->bv_offset & (dev->ctrl.page_size - 1);
+	unsigned int first_prp_len = dev->ctrl.page_size - offset;
 
 	iod->first_dma = dma_map_bvec(dev->dev, bv, rq_dma_dir(req), 0);
 	if (dma_mapping_error(dev->dev, iod->first_dma))
-- 
2.14.4