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nvmet-rdma: Fix missing dma sync to nvme data structures

PATCH New Parav Pandit 3 participants 5 messages Jan 14, 2017 – Jan 16, 2017

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InfiniBand NVMe NVMe target
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Parav Pandit

author
#0 lore raw

PATCH 1/1 nvmet-rdma: Fix missing dma sync to nvme data structures

This patch performs dma sync operations on nvme_command, inline page(s) and nvme_completion.

nvme_command and write cmd inline data is synced
(a) on receiving of the recv queue completion for cpu access.
(b) before posting recv wqe back to rdma adapter for device access.

nvme_completion is synced
(a) on receiving send completion for nvme_completion for cpu access.
(b) before posting send wqe to rdma adapter for device access.

Signed-off-by Parav Pandit <parav at mellanox.com>
Reviewed-by Max Gurtovoy <maxg at mellanox.com>
---
 drivers/nvme/target/rdma.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)
drivers/nvme/target/rdma.c +26 -0
index 6c1c368..da3d553 100644
@@ -438,6 +438,14 @@ static int nvmet_rdma_post_recv(struct nvmet_rdma_device *ndev,
 {
 	struct ib_recv_wr *bad_wr;
 
+	ib_dma_sync_single_for_device(ndev->device,
+			cmd->sge[0].addr, sizeof(*cmd->nvme_cmd),
+			DMA_FROM_DEVICE);
+
+	if (cmd->sge[1].addr)
+		ib_dma_sync_single_for_device(ndev->device,
+				cmd->sge[1].addr, NVMET_RDMA_INLINE_DATA_SIZE,
+				DMA_FROM_DEVICE);
 	if (ndev->srq)
 		return ib_post_srq_recv(ndev->srq, &cmd->wr, &bad_wr);
 	return ib_post_recv(cmd->queue->cm_id->qp, &cmd->wr, &bad_wr);

@@ -507,6 +515,10 @@ static void nvmet_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc)
 	struct nvmet_rdma_rsp *rsp =
 		container_of(wc->wr_cqe, struct nvmet_rdma_rsp, send_cqe);
 
+	ib_dma_sync_single_for_cpu(rsp->queue->dev->device,
+			rsp->send_sge.addr, sizeof(*rsp->req.rsp),
+			DMA_TO_DEVICE);
+
 	nvmet_rdma_release_rsp(rsp);
 
 	if (unlikely(wc->status != IB_WC_SUCCESS &&

@@ -538,6 +550,11 @@ static void nvmet_rdma_queue_response(struct nvmet_req *req)
 		first_wr = &rsp->send_wr;
 
 	nvmet_rdma_post_recv(rsp->queue->dev, rsp->cmd);
+
+	ib_dma_sync_single_for_device(rsp->queue->dev->device,
+			rsp->send_sge.addr, sizeof(*rsp->req.rsp),
+			DMA_TO_DEVICE);
+
 	if (ib_post_send(cm_id->qp, first_wr, &bad_wr)) {
 		pr_err("sending cmd response failed\n");
 		nvmet_rdma_release_rsp(rsp);

@@ -698,6 +715,15 @@ static void nvmet_rdma_handle_command(struct nvmet_rdma_queue *queue,
 	cmd->n_rdma = 0;
 	cmd->req.port = queue->port;
 
+	ib_dma_sync_single_for_cpu(queue->dev->device, cmd->cmd->sge[0].addr,
+			sizeof(*cmd->cmd->nvme_cmd), DMA_FROM_DEVICE);
+
+	if (cmd->cmd->sge[1].addr)
+		ib_dma_sync_single_for_cpu(queue->dev->device,
+				cmd->cmd->sge[1].addr,
+				NVMET_RDMA_INLINE_DATA_SIZE,
+				DMA_FROM_DEVICE);
+
 	if (!nvmet_req_init(&cmd->req, &queue->nvme_cq,
 			&queue->nvme_sq, &nvmet_rdma_ops))
 		return;
Signature · 1 line
1.8.3.1
maintainer
#1 lore raw

PATCH 1/1 nvmet-rdma: Fix missing dma sync to nvme data structures

Looks good,

Reviewed-by Sagi Grimberg <sagi at grimberg.me>

When this is applied, will add stable 4.8+ tag.

maintainer
#2 lore raw

PATCH 1/1 nvmet-rdma: Fix missing dma sync to nvme data structures

In reply to Parav Pandit

drivers/nvme/target/rdma.c static int nvmet_rdma_post_recv(struct nvmet_rdma_device *ndev, · line 445

Quoted 10 lines

+++ b/drivers/nvme/target/rdma.c

drivers/nvme/target/rdma.c +5 -0
@@ -438,6 +438,14 @@ static int nvmet_rdma_post_recv(struct nvmet_rdma_device *ndev,
 {
 	struct ib_recv_wr *bad_wr;
 
+	ib_dma_sync_single_for_device(ndev->device,
+			cmd->sge[0].addr, sizeof(*cmd->nvme_cmd),
+			DMA_FROM_DEVICE);
+
+	if (cmd->sge[1].addr)

0 can be a valid address returned from dma_map_single on some architectures.

author
#3 lore raw

PATCH 1/1 nvmet-rdma: Fix missing dma sync to nvme data structures

Quoted 16 lines

-----Original Message-----
From: Christoph Hellwig [mailto:hch at lst.de]
Sent: Monday, January 16, 2017 9:31 AM
To: Parav Pandit <parav at mellanox.com>
Cc: hch at lst.de; sagi at grimberg.me; linux-nvme at lists.infradead.org; linux- rdma at vger.kernel.org; dledford at redhat.com
Subject: Re: [PATCH] nvmet-rdma: Fix missing dma sync to nvme data structures

Quoted 5 lines

+++ b/drivers/nvme/target/rdma.c

drivers/nvme/target/rdma.c +0 -0
@@ -438,6 +438,14 @@ static int nvmet_rdma_post_recv(struct
 nvmet_rdma_device *ndev,  {
 	struct ib_recv_wr *bad_wr;
Quoted 8 lines

drivers/nvme/target/rdma.c static int nvmet_rdma_post_recv(struct nvmet_rdma_device *ndev, · line 445

Quoted 5 lines
drivers/nvme/target/rdma.c +5 -0
+	ib_dma_sync_single_for_device(ndev->device,
+			cmd->sge[0].addr, sizeof(*cmd->nvme_cmd),
+			DMA_FROM_DEVICE);
+
+	if (cmd->sge[1].addr)

0 can be a valid address returned from dma_map_single on some architectures.

I see. I will change it to check for the non-zero length instead of non-zero address.

maintainer
#4 lore raw

PATCH 1/1 nvmet-rdma: Fix missing dma sync to nvme data structures

Quoted 1 line · Parav Pandit

I see. I will change it to check for the non-zero length instead of non-zero address.

Yes, that should work as well.