[PATCH v23 07/20] nvme-tcp: RX DDGST offload

Sagi Grimberg sagi at grimberg.me
Thu Mar 7 01:18:05 PST 2024



On 28/02/2024 14:57, Aurelien Aptel wrote:
> From: Yoray Zack <yorayz at nvidia.com>
>
> Enable rx side of DDGST offload when supported.
>
> At the end of the capsule, check if all the skb bits are on, and if not
> recalculate the DDGST in SW and check it.
>
> Signed-off-by: Yoray Zack <yorayz at nvidia.com>
> Signed-off-by: Boris Pismenny <borisp at nvidia.com>
> Signed-off-by: Ben Ben-Ishay <benishay at nvidia.com>
> Signed-off-by: Or Gerlitz <ogerlitz at nvidia.com>
> Signed-off-by: Shai Malin <smalin at nvidia.com>
> Signed-off-by: Aurelien Aptel <aaptel at nvidia.com>
> Reviewed-by: Chaitanya Kulkarni <kch at nvidia.com>
> Reviewed-by: Max Gurtovoy <mgurtovoy at nvidia.com>
> ---
>   drivers/nvme/host/tcp.c | 96 ++++++++++++++++++++++++++++++++++++++---
>   1 file changed, 91 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
> index b7cfe14661d6..2eebd9d2aee5 100644
> --- a/drivers/nvme/host/tcp.c
> +++ b/drivers/nvme/host/tcp.c
> @@ -143,6 +143,7 @@ enum nvme_tcp_queue_flags {
>   	NVME_TCP_Q_LIVE		= 1,
>   	NVME_TCP_Q_POLLING	= 2,
>   	NVME_TCP_Q_OFF_DDP	= 3,
> +	NVME_TCP_Q_OFF_DDGST_RX = 4,
>   };
>   
>   enum nvme_tcp_recv_state {
> @@ -180,6 +181,7 @@ struct nvme_tcp_queue {
>   	 *   is pending (ULP_DDP_RESYNC_PENDING).
>   	 */
>   	atomic64_t		resync_tcp_seq;
> +	bool			ddp_ddgst_valid;
>   #endif
>   
>   	/* send state */
> @@ -393,6 +395,46 @@ nvme_tcp_get_ddp_netdev_with_limits(struct nvme_tcp_ctrl *ctrl)
>   	return NULL;
>   }
>   
> +static inline bool nvme_tcp_ddp_ddgst_ok(struct nvme_tcp_queue *queue)
> +{
> +	return queue->ddp_ddgst_valid;
> +}
> +
> +static inline void nvme_tcp_ddp_ddgst_update(struct nvme_tcp_queue *queue,
> +					     struct sk_buff *skb)
> +{
> +	if (queue->ddp_ddgst_valid)
> +		queue->ddp_ddgst_valid = skb_is_ulp_crc(skb);
> +}
> +
> +static void nvme_tcp_ddp_ddgst_recalc(struct ahash_request *hash,
> +				      struct request *rq,
> +				      __le32 *ddgst)
> +{
> +	struct nvme_tcp_request *req;
> +
> +	req = blk_mq_rq_to_pdu(rq);
> +	if (!req->offloaded) {
> +		/* if we have DDGST_RX offload but DDP was skipped
> +		 * because it's under the min IO threshold then the
> +		 * request won't have an SGL, so we need to make it
> +		 * here
> +		 */
> +		if (nvme_tcp_ddp_alloc_sgl(req, rq))
> +			return;
> +	}
> +
> +	ahash_request_set_crypt(hash, req->ddp.sg_table.sgl, (u8 *)ddgst,
> +				req->data_len);
> +	crypto_ahash_digest(hash);
> +	if (!req->offloaded) {
> +		/* without DDP, ddp_teardown() won't be called, so
> +		 * free the table here
> +		 */
> +		sg_free_table_chained(&req->ddp.sg_table, SG_CHUNK_SIZE);
> +	}
> +}
> +
>   static bool nvme_tcp_resync_request(struct sock *sk, u32 seq, u32 flags);
>   static void nvme_tcp_ddp_teardown_done(void *ddp_ctx);
>   static const struct ulp_ddp_ulp_ops nvme_tcp_ddp_ulp_ops = {
> @@ -478,6 +520,10 @@ static int nvme_tcp_offload_socket(struct nvme_tcp_queue *queue)
>   		return ret;
>   
>   	set_bit(NVME_TCP_Q_OFF_DDP, &queue->flags);
> +	if (queue->data_digest &&
> +	    ulp_ddp_is_cap_active(queue->ctrl->ddp_netdev,
> +				  ULP_DDP_CAP_NVME_TCP_DDGST_RX))
> +		set_bit(NVME_TCP_Q_OFF_DDGST_RX, &queue->flags);
>   
>   	return 0;
>   }
> @@ -485,6 +531,7 @@ static int nvme_tcp_offload_socket(struct nvme_tcp_queue *queue)
>   static void nvme_tcp_unoffload_socket(struct nvme_tcp_queue *queue)
>   {
>   	clear_bit(NVME_TCP_Q_OFF_DDP, &queue->flags);
> +	clear_bit(NVME_TCP_Q_OFF_DDGST_RX, &queue->flags);
>   	ulp_ddp_sk_del(queue->ctrl->ddp_netdev, queue->sock->sk);
>   }
>   
> @@ -593,6 +640,20 @@ static void nvme_tcp_resync_response(struct nvme_tcp_queue *queue,
>   				     struct sk_buff *skb, unsigned int offset)
>   {}
>   
> +static inline bool nvme_tcp_ddp_ddgst_ok(struct nvme_tcp_queue *queue)
> +{
> +	return false;
> +}
> +
> +static inline void nvme_tcp_ddp_ddgst_update(struct nvme_tcp_queue *queue,
> +					     struct sk_buff *skb)
> +{}
> +
> +static void nvme_tcp_ddp_ddgst_recalc(struct ahash_request *hash,
> +				      struct request *rq,
> +				      __le32 *ddgst)
> +{}
> +
>   #endif
>   
>   static void nvme_tcp_init_iter(struct nvme_tcp_request *req,
> @@ -853,6 +914,9 @@ static void nvme_tcp_init_recv_ctx(struct nvme_tcp_queue *queue)
>   	queue->pdu_offset = 0;
>   	queue->data_remaining = -1;
>   	queue->ddgst_remaining = 0;
> +#ifdef CONFIG_ULP_DDP
> +	queue->ddp_ddgst_valid = true;
> +#endif
>   }
>   
>   static void nvme_tcp_error_recovery(struct nvme_ctrl *ctrl)
> @@ -1118,6 +1182,9 @@ static int nvme_tcp_recv_data(struct nvme_tcp_queue *queue, struct sk_buff *skb,
>   		nvme_cid_to_rq(nvme_tcp_tagset(queue), pdu->command_id);
>   	struct nvme_tcp_request *req = blk_mq_rq_to_pdu(rq);
>   
> +	if (test_bit(NVME_TCP_Q_OFF_DDGST_RX, &queue->flags))
> +		nvme_tcp_ddp_ddgst_update(queue, skb);
> +
>   	while (true) {
>   		int recv_len, ret;
>   
> @@ -1146,7 +1213,8 @@ static int nvme_tcp_recv_data(struct nvme_tcp_queue *queue, struct sk_buff *skb,
>   		recv_len = min_t(size_t, recv_len,
>   				iov_iter_count(&req->iter));
>   
> -		if (queue->data_digest)
> +		if (queue->data_digest &&
> +		    !test_bit(NVME_TCP_Q_OFF_DDGST_RX, &queue->flags))
>   			ret = skb_copy_and_hash_datagram_iter(skb, *offset,
>   				&req->iter, recv_len, queue->rcv_hash);
>   		else
> @@ -1188,8 +1256,11 @@ static int nvme_tcp_recv_ddgst(struct nvme_tcp_queue *queue,
>   	char *ddgst = (char *)&queue->recv_ddgst;
>   	size_t recv_len = min_t(size_t, *len, queue->ddgst_remaining);
>   	off_t off = NVME_TCP_DIGEST_LENGTH - queue->ddgst_remaining;
> +	struct request *rq;
>   	int ret;
>   
> +	if (test_bit(NVME_TCP_Q_OFF_DDGST_RX, &queue->flags))
> +		nvme_tcp_ddp_ddgst_update(queue, skb);
>   	ret = skb_copy_bits(skb, *offset, &ddgst[off], recv_len);
>   	if (unlikely(ret))
>   		return ret;
> @@ -1200,9 +1271,25 @@ static int nvme_tcp_recv_ddgst(struct nvme_tcp_queue *queue,
>   	if (queue->ddgst_remaining)
>   		return 0;
>   
> +	rq = nvme_cid_to_rq(nvme_tcp_tagset(queue),
> +			    pdu->command_id);
> +
> +	if (test_bit(NVME_TCP_Q_OFF_DDGST_RX, &queue->flags)) {
> +		/*
> +		 * If HW successfully offloaded the digest
> +		 * verification, we can skip it
> +		 */
> +		if (nvme_tcp_ddp_ddgst_ok(queue))
> +			goto out;
> +		/*
> +		 * Otherwise we have to recalculate and verify the
> +		 * digest with the software-fallback
> +		 */
> +		nvme_tcp_ddp_ddgst_recalc(queue->rcv_hash, rq,
> +					  &queue->exp_ddgst);
> +	}
> +
>   	if (queue->recv_ddgst != queue->exp_ddgst) {
> -		struct request *rq = nvme_cid_to_rq(nvme_tcp_tagset(queue),
> -					pdu->command_id);
>   		struct nvme_tcp_request *req = blk_mq_rq_to_pdu(rq);
>   
>   		req->status = cpu_to_le16(NVME_SC_DATA_XFER_ERROR);
> @@ -1213,9 +1300,8 @@ static int nvme_tcp_recv_ddgst(struct nvme_tcp_queue *queue,
>   			le32_to_cpu(queue->exp_ddgst));
>   	}
>   
> +out:

Nit: you can rename the label to ddgst_valid: or ddgst_ok:

Other than that,
Reviewed-by: Sagi Grimberg <sagi at grimberg.me>



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