Re: [PATCH 16/18] nvmet-tcp: rework sendpage for kTLS

Sagi Grimberg
2023-03-22T12:16:30Z

> kTLS ->sendpage() doesn't support the MSG_EOR flag, and it's
> questionable whether it makes sense for kTLS as one has to copy
> data anyway.
> So use sock_no_sendpage() for kTLS.

Same comments as the host side.
1. separate MSG_EOR from kernel_sendpage
2. keep kernel_sendpage unless unsupported properly.

>
> Signed-off-by: Hannes Reinecke <hare@suse.de>
> ---
> drivers/nvme/target/tcp.c | 56 ++++++++++++++++++++++++++++-----------
> 1 file changed, 41 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
> index 6e88e98a2c59..9b69cac84508 100644
> --- a/drivers/nvme/target/tcp.c
> +++ b/drivers/nvme/target/tcp.c
> @@ -570,9 +570,14 @@ static int nvmet_try_send_data_pdu(struct nvmet_tcp_cmd *cmd)
> int left = sizeof(*cmd->data_pdu) - cmd->offset + hdgst;
> int ret;
>
> - ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->data_pdu),
> - offset_in_page(cmd->data_pdu) + cmd->offset,
> - left, MSG_DONTWAIT | MSG_MORE | MSG_SENDPAGE_NOTLAST);
> + if (cmd->queue->tls_psk)
> + ret = sock_no_sendpage(cmd->queue->sock, virt_to_page(cmd->data_pdu),
> + offset_in_page(cmd->data_pdu) + cmd->offset,
> + left, MSG_DONTWAIT | MSG_MORE);
> + else
> + ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->data_pdu),
> + offset_in_page(cmd->data_pdu) + cmd->offset,
> + left, MSG_DONTWAIT | MSG_MORE | MSG_SENDPAGE_NOTLAST);
> if (ret <= 0)
> return ret;
>
> @@ -600,10 +605,17 @@ static int nvmet_try_send_data(struct nvmet_tcp_cmd *cmd, bool last_in_batch)
> if ((!last_in_batch && cmd->queue->send_list_len) ||
> cmd->wbytes_done + left < cmd->req.transfer_len ||
> queue->data_digest || !queue->nvme_sq.sqhd_disabled)
> - flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST;
> -
> - ret = kernel_sendpage(cmd->queue->sock, page, cmd->offset,
> - left, flags);
> + flags |= MSG_MORE;
> +
> + if (queue->tls_psk)
> + ret = sock_no_sendpage(cmd->queue->sock, page, cmd->offset,
> + left, flags);
> + else {
> + if (flags & MSG_MORE)
> + flags |= MSG_SENDPAGE_NOTLAST;
> + ret = kernel_sendpage(cmd->queue->sock, page, cmd->offset,
> + left, flags);
> + }
> if (ret <= 0)
> return ret;
>
> @@ -645,12 +657,19 @@ static int nvmet_try_send_response(struct nvmet_tcp_cmd *cmd,
> int ret;
>
> if (!last_in_batch && cmd->queue->send_list_len)
> - flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST;
> - else
> + flags |= MSG_MORE;
> + else if (!cmd->queue->tls_psk)
> flags |= MSG_EOR;
>
> - ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->rsp_pdu),
> - offset_in_page(cmd->rsp_pdu) + cmd->offset, left, flags);
> + if (cmd->queue->tls_psk)
> + ret = sock_no_sendpage(cmd->queue->sock, virt_to_page(cmd->rsp_pdu),
> + offset_in_page(cmd->rsp_pdu) + cmd->offset, left, flags);
> + else {
> + if (flags & MSG_MORE)
> + flags |= MSG_SENDPAGE_NOTLAST;
> + ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->rsp_pdu),
> + offset_in_page(cmd->rsp_pdu) + cmd->offset, left, flags);
> + }
> if (ret <= 0)
> return ret;
> cmd->offset += ret;
> @@ -673,12 +692,19 @@ static int nvmet_try_send_r2t(struct nvmet_tcp_cmd *cmd, bool last_in_batch)
> int ret;
>
> if (!last_in_batch && cmd->queue->send_list_len)
> - flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST;
> - else
> + flags |= MSG_MORE;
> + else if (!cmd->queue->tls_psk)
> flags |= MSG_EOR;
>
> - ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->r2t_pdu),
> - offset_in_page(cmd->r2t_pdu) + cmd->offset, left, flags);
> + if (cmd->queue->tls_psk)
> + ret = sock_no_sendpage(cmd->queue->sock, virt_to_page(cmd->r2t_pdu),
> + offset_in_page(cmd->r2t_pdu) + cmd->offset, left, flags);
> + else {
> + if (flags & MSG_MORE)
> + flags |= MSG_SENDPAGE_NOTLAST;
> + ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->r2t_pdu),
> + offset_in_page(cmd->r2t_pdu) + cmd->offset, left, flags);
> + }
> if (ret <= 0)
> return ret;
> cmd->offset += ret;