From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 05BD4C4CECE for ; Tue, 15 Oct 2019 00:34:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C5C0E217F9 for ; Tue, 15 Oct 2019 00:34:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="imtzrVDY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727063AbfJOAeS (ORCPT ); Mon, 14 Oct 2019 20:34:18 -0400 Received: from mail-pf1-f193.google.com ([209.85.210.193]:42968 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726525AbfJOAeS (ORCPT ); Mon, 14 Oct 2019 20:34:18 -0400 Received: by mail-pf1-f193.google.com with SMTP id q12so11294248pff.9; Mon, 14 Oct 2019 17:34:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=p63sdX+Vdm+k9Q/K8b8bZcwryvDdi7+PCTGQ3bkMavU=; b=imtzrVDYOhDb9/YBqDjfqrkETYkU9AyX8BQUP5CpRE6I71aSaE+YG1IImuLT79wZbZ EZU6AVpnMlH+1H5maCD34DFb5lYcXTgkv35FmgWjd7TbCKdtvCJ35yti4mrSIZwGxqth mHUy3chTY2JVnT2lB9EHj3aZl0UTN9S4x1ABpEperXS007ppUQ6uVQXfn7Oe2LQKhxUA 7DkDHcTT+VnmXTJGIV8NC+J5hCaDL3pvgg1lsmCt0x/cm3KgKBXhTseuzP7LT6LgSXGS kB9xcdCCD70S+D0tVCFKnUJPy1IYtiLysJERFx0oq4ZvsKnF9gUUo0b8qqAGotP8tSDG XMhQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=p63sdX+Vdm+k9Q/K8b8bZcwryvDdi7+PCTGQ3bkMavU=; b=A5CYvI2X/dK3rQbchZmqOP8tyoWfVM88uxTj23ZqrRt5UXsFm6c9nZCuP8BWcmJz7L YbYCO0cRjcVuBhkNXxyELNH/zpkywd6D+AMCswvRKYKZaKn0TV9kGyK0W0AnxIIPArEN QMt2uHHfRYHXkAnEL0Kd/fAj3EJ50pN92XBeDq01oVcUTV5BwxK5OSA2m24WbXlktfb0 RT24jPbSisuFK+lopAH5HxKTGIzao6PsfRkdJWeT4qNkBaIoeQnZFCDQajuvBO14cWfw ByTtV5B6A+KpXC6dwrC0lrQg+BBuR8BZk3lAYxVmXAEFrj96fXPXoKxOPxCSp6w5nXzR e9fg== X-Gm-Message-State: APjAAAWxL1yh12LoyEBRjQtLip/RoLQpevxIntVq26oPY2fQAkzFlPcp ihJXE4ISa1Sx5dGnxM1LN/gub87V X-Google-Smtp-Source: APXvYqz+E34/dO6gMNpeSAMB6A0OsVDc28bUq28UDzqCg991LYJ0c2nmez5bgrso2AkovfLe9ZKTiQ== X-Received: by 2002:a65:51cd:: with SMTP id i13mr36383031pgq.142.1571099655427; Mon, 14 Oct 2019 17:34:15 -0700 (PDT) Received: from [172.20.20.156] ([222.151.198.97]) by smtp.gmail.com with ESMTPSA id j24sm19366486pff.71.2019.10.14.17.34.13 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 14 Oct 2019 17:34:14 -0700 (PDT) Subject: Re: [PATCH net-next 1/3] tuntap: reorganize tun_msg_ctl usage To: Jason Wang , "Michael S . Tsirkin" , "David S . Miller" Cc: David Ahern , kvm@vger.kernel.org, netdev@vger.kernel.org References: <20191012015357.1775-1-prashantbhole.linux@gmail.com> <20191012015357.1775-2-prashantbhole.linux@gmail.com> <739281a8-59fe-d898-0147-656d01fdfabc@redhat.com> From: Prashant Bhole Message-ID: <18ab09ed-55b9-babb-6d78-04a920918562@gmail.com> Date: Tue, 15 Oct 2019 09:33:42 +0900 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <739281a8-59fe-d898-0147-656d01fdfabc@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hi Jason, Thanks for reviewing. On 10/12/19 4:44 PM, Jason Wang wrote: > > On 2019/10/12 上午9:53, prashantbhole.linux@gmail.com wrote: >> From: Prashant Bhole >> >> In order to extend the usage of tun_msg_ctl structure, this patch >> changes the member name from type to cmd. Also following definitions >> are changed: >> TUN_MSG_PTR : TUN_CMD_BATCH >> TUN_MSG_UBUF: TUN_CMD_PACKET > > > Not a native English speaker, but the conversion here looks not as > straightforward as it did. > > For TUN_MSG_PTR, it means recvmsg() can do receiving from a pointer to > either XDP or skb instead of ptr_ring. TUN_CMD_BATCH sounds not related. > > For TUN_MSG_UBUF, it means the packet is a zercopy (buffer pointers to > userspace). TUN_CMD_PACKET may bring confusion in this case. Understood. Next time I will come up with better command names, performance numbers and other changes suggested by you. Thanks. > > Thanks > > >> >> Signed-off-by: Prashant Bhole >> --- >>   drivers/net/tap.c      | 9 ++++++--- >>   drivers/net/tun.c      | 8 ++++++-- >>   drivers/vhost/net.c    | 4 ++-- >>   include/linux/if_tun.h | 6 +++--- >>   4 files changed, 17 insertions(+), 10 deletions(-) >> >> diff --git a/drivers/net/tap.c b/drivers/net/tap.c >> index 3ae70c7e6860..01bd260ce60c 100644 >> --- a/drivers/net/tap.c >> +++ b/drivers/net/tap.c >> @@ -1213,9 +1213,10 @@ static int tap_sendmsg(struct socket *sock, >> struct msghdr *m, >>       struct tap_queue *q = container_of(sock, struct tap_queue, sock); >>       struct tun_msg_ctl *ctl = m->msg_control; >>       struct xdp_buff *xdp; >> +    void *ptr = NULL; >>       int i; >> -    if (ctl && (ctl->type == TUN_MSG_PTR)) { >> +    if (ctl && ctl->cmd == TUN_CMD_BATCH) { >>           for (i = 0; i < ctl->num; i++) { >>               xdp = &((struct xdp_buff *)ctl->ptr)[i]; >>               tap_get_user_xdp(q, xdp); >> @@ -1223,8 +1224,10 @@ static int tap_sendmsg(struct socket *sock, >> struct msghdr *m, >>           return 0; >>       } >> -    return tap_get_user(q, ctl ? ctl->ptr : NULL, &m->msg_iter, >> -                m->msg_flags & MSG_DONTWAIT); >> +    if (ctl && ctl->cmd == TUN_CMD_PACKET) >> +        ptr = ctl->ptr; >> + >> +    return tap_get_user(q, ptr, &m->msg_iter, m->msg_flags & >> MSG_DONTWAIT); >>   } >>   static int tap_recvmsg(struct socket *sock, struct msghdr *m, >> diff --git a/drivers/net/tun.c b/drivers/net/tun.c >> index 0413d182d782..29711671959b 100644 >> --- a/drivers/net/tun.c >> +++ b/drivers/net/tun.c >> @@ -2529,11 +2529,12 @@ static int tun_sendmsg(struct socket *sock, >> struct msghdr *m, size_t total_len) >>       struct tun_struct *tun = tun_get(tfile); >>       struct tun_msg_ctl *ctl = m->msg_control; >>       struct xdp_buff *xdp; >> +    void *ptr = NULL; >>       if (!tun) >>           return -EBADFD; >> -    if (ctl && (ctl->type == TUN_MSG_PTR)) { >> +    if (ctl && ctl->cmd == TUN_CMD_BATCH) { >>           struct tun_page tpage; >>           int n = ctl->num; >>           int flush = 0; >> @@ -2560,7 +2561,10 @@ static int tun_sendmsg(struct socket *sock, >> struct msghdr *m, size_t total_len) >>           goto out; >>       } >> -    ret = tun_get_user(tun, tfile, ctl ? ctl->ptr : NULL, &m->msg_iter, >> +    if (ctl && ctl->cmd == TUN_CMD_PACKET) >> +        ptr = ctl->ptr; >> + >> +    ret = tun_get_user(tun, tfile, ptr, &m->msg_iter, >>                  m->msg_flags & MSG_DONTWAIT, >>                  m->msg_flags & MSG_MORE); >>   out: >> diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c >> index 1a2dd53caade..5946d2775bd0 100644 >> --- a/drivers/vhost/net.c >> +++ b/drivers/vhost/net.c >> @@ -462,7 +462,7 @@ static void vhost_tx_batch(struct vhost_net *net, >>                  struct msghdr *msghdr) >>   { >>       struct tun_msg_ctl ctl = { >> -        .type = TUN_MSG_PTR, >> +        .cmd = TUN_CMD_BATCH, >>           .num = nvq->batched_xdp, >>           .ptr = nvq->xdp, >>       }; >> @@ -902,7 +902,7 @@ static void handle_tx_zerocopy(struct vhost_net >> *net, struct socket *sock) >>               ubuf->desc = nvq->upend_idx; >>               refcount_set(&ubuf->refcnt, 1); >>               msg.msg_control = &ctl; >> -            ctl.type = TUN_MSG_UBUF; >> +            ctl.cmd = TUN_CMD_PACKET; >>               ctl.ptr = ubuf; >>               msg.msg_controllen = sizeof(ctl); >>               ubufs = nvq->ubufs; >> diff --git a/include/linux/if_tun.h b/include/linux/if_tun.h >> index 5bda8cf457b6..bdfa671612db 100644 >> --- a/include/linux/if_tun.h >> +++ b/include/linux/if_tun.h >> @@ -11,10 +11,10 @@ >>   #define TUN_XDP_FLAG 0x1UL >> -#define TUN_MSG_UBUF 1 >> -#define TUN_MSG_PTR  2 >> +#define TUN_CMD_PACKET 1 >> +#define TUN_CMD_BATCH  2 >>   struct tun_msg_ctl { >> -    unsigned short type; >> +    unsigned short cmd; >>       unsigned short num; >>       void *ptr; >>   };