From patchwork Tue Mar 5 02:01:45 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mina Almasry X-Patchwork-Id: 13581493 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 898AAC54E49 for ; Tue, 5 Mar 2024 02:02:25 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 138A311282D; Tue, 5 Mar 2024 02:02:23 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.b="m7opawKi"; dkim-atps=neutral Received: from mail-yb1-f202.google.com (mail-yb1-f202.google.com [209.85.219.202]) by gabe.freedesktop.org (Postfix) with ESMTPS id 41A70112829 for ; Tue, 5 Mar 2024 02:02:20 +0000 (UTC) Received: by mail-yb1-f202.google.com with SMTP id 3f1490d57ef6-dd0ae66422fso225730276.0 for ; Mon, 04 Mar 2024 18:02:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1709604139; x=1710208939; darn=lists.freedesktop.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=kFOLH8z6Kc1/DHNjJCRtctXlk4wkt0G4E5LxaUbD2lM=; b=m7opawKiQ1ZkrgIeovAy5jEwHh5i5wjnL5FiPB9ILIwwuipWWCNNXXyWVV5DcWA/+j jSZcXTwtws36tVSvR4fAYPwEqsTor7d/XXRlf7WOe1CosAQvTEPcFmcpVkeAvoRZ2KR5 Nn1wOYmTwdd84izQ4UpMxxfziw9ORZNDI7aU+CMP0rYVs2Rt8RPuaiFQ9NEB6lpK+EEN B6hCO4vqhG1CV22fqyV7inepoUWoNdDxgpNFHKNutOTvB4oLjhFIcgEdjkLeHAZnDQa2 lqglI/vpum/mH8x2ATtQSWqfPrBTb4tzJXIoNsQKezILUzEXfx8i5e49ISE5YzT7zYcl SLXQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1709604139; x=1710208939; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=kFOLH8z6Kc1/DHNjJCRtctXlk4wkt0G4E5LxaUbD2lM=; b=Vrmqpj07PE5Xbjv8G6O5kQXEaWAl/UC8manFHWdJz6Ct1NRfRHOX2bcDy8IM0BspQu PyRnFxJB6a4gQeMKsprAO09RjKZoExw52o+sABH8bxcezdWqyyguWaO/VcVtp9WteF6x eN6gL4TdjFpGyf6bAAt6bkh/KFkT9JWlWAIi75KYCSXrYwXph2Ecaq6rHmXCUXtX4wxq Cah/Fev6em637We/ne8SNzN3XRtRh6rgwu2Hd/w5fAOqerHMH+O1KujnhDgnbGD+2Xxz PTRLLq0VHVEmYdpC9A73Sa7t2G2ut3zny7fMxqIf0yi0DhbJzLoLxRwL32h/Id/oyl0f 4ADg== X-Forwarded-Encrypted: i=1; AJvYcCUmkP12+ZSRw1AXCTcs3VHPpo26tuQHWBWZjmje+GGYfUZWUxb0M2dpPkiRHvfAU+3cupq3OGoNeECLvSr1aFPhqX7Vwy4yiIXTv17Na60+ X-Gm-Message-State: AOJu0YwlBP48Ge38GX3pE/sgEIerwRpGQhJzl2ImNAsw092cB8To0l+g WnRlekPIO+sOt5z5iHSLlfM1POJfueQfjvrklDZf8nKLUPW+kLjbtCxEgVOmfK/oEnTDMdNX76N IBTF9DM4UQELP9uvFbGZu8A== X-Google-Smtp-Source: AGHT+IERAxLDH9CLsybVTiG1Kl+Ij4FHQxio+Skkp7XFr1VDsZ/QGA1eBFcDme38Y+MfcJE7+b6HhIBoi+3CQvIBng== X-Received: from almasrymina.svl.corp.google.com ([2620:15c:2c4:200:b614:914c:63cd:3830]) (user=almasrymina job=sendgmr) by 2002:a05:6902:1504:b0:dbd:b4e8:1565 with SMTP id q4-20020a056902150400b00dbdb4e81565mr342247ybu.4.1709604139120; Mon, 04 Mar 2024 18:02:19 -0800 (PST) Date: Mon, 4 Mar 2024 18:01:45 -0800 In-Reply-To: <20240305020153.2787423-1-almasrymina@google.com> Mime-Version: 1.0 References: <20240305020153.2787423-1-almasrymina@google.com> X-Mailer: git-send-email 2.44.0.rc1.240.g4c46232300-goog Message-ID: <20240305020153.2787423-11-almasrymina@google.com> Subject: [RFC PATCH net-next v6 10/15] net: support non paged skb frags From: Mina Almasry To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-alpha@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, sparclinux@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-arch@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org Cc: Mina Almasry , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Jonathan Corbet , Richard Henderson , Ivan Kokshaysky , Matt Turner , Thomas Bogendoerfer , "James E.J. Bottomley" , Helge Deller , Andreas Larsson , Jesper Dangaard Brouer , Ilias Apalodimas , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Arnd Bergmann , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , David Ahern , Willem de Bruijn , Shuah Khan , Sumit Semwal , " =?utf-8?q?Christian_K=C3=B6nig?= " , Pavel Begunkov , David Wei , Jason Gunthorpe , Yunsheng Lin , Shailend Chand , Harshitha Ramamurthy , Shakeel Butt , Jeroen de Borst , Praveen Kaligineedi X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Make skb_frag_page() fail in the case where the frag is not backed by a page, and fix its relevant callers to handle this case. Signed-off-by: Mina Almasry --- v6: - Rebased on top of the merged netmem changes. Changes in v1: - Fix illegal_highdma() (Yunsheng). - Rework napi_pp_put_page() slightly to reduce code churn (Willem). --- include/linux/skbuff.h | 47 +++++++++++++++++++++++++++++++++++++----- net/core/dev.c | 3 ++- net/core/gro.c | 2 +- net/core/skbuff.c | 11 ++++++++++ net/ipv4/tcp.c | 3 +++ 5 files changed, 59 insertions(+), 7 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index ca29d1fd4561..d68d430dc596 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -3466,17 +3466,53 @@ static inline void skb_frag_off_copy(skb_frag_t *fragto, fragto->offset = fragfrom->offset; } +/* Returns true if the skb_frag contains a net_iov. */ +static inline bool skb_frag_is_net_iov(const skb_frag_t *frag) +{ + return netmem_is_net_iov(frag->netmem); +} + +/** + * skb_frag_net_iov - retrieve the net_iov referred to by fragment + * @frag: the fragment + * + * Returns the &struct net_iov associated with @frag. Returns NULL if this + * frag has no associated net_iov. + */ +static inline struct net_iov *skb_frag_net_iov(const skb_frag_t *frag) +{ + if (!skb_frag_is_net_iov(frag)) + return NULL; + + return netmem_to_net_iov(frag->netmem); +} + /** * skb_frag_page - retrieve the page referred to by a paged fragment * @frag: the paged fragment * - * Returns the &struct page associated with @frag. + * Returns the &struct page associated with @frag. Returns NULL if this frag + * has no associated page. */ static inline struct page *skb_frag_page(const skb_frag_t *frag) { + if (skb_frag_is_net_iov(frag)) + return NULL; + return netmem_to_page(frag->netmem); } +/** + * skb_frag_netmem - retrieve the netmem referred to by a fragment + * @frag: the fragment + * + * Returns the &netmem_ref associated with @frag. + */ +static inline netmem_ref skb_frag_netmem(const skb_frag_t *frag) +{ + return frag->netmem; +} + /** * __skb_frag_ref - take an addition reference on a paged fragment. * @frag: the paged fragment @@ -3509,13 +3545,11 @@ bool napi_pp_put_page(netmem_ref netmem, bool napi_safe); static inline void napi_frag_unref(skb_frag_t *frag, bool recycle, bool napi_safe) { - struct page *page = skb_frag_page(frag); - #ifdef CONFIG_PAGE_POOL - if (recycle && napi_pp_put_page(page_to_netmem(page), napi_safe)) + if (recycle && napi_pp_put_page(skb_frag_netmem(frag), napi_safe)) return; #endif - put_page(page); + put_page(skb_frag_page(frag)); } /** @@ -3555,6 +3589,9 @@ static inline void skb_frag_unref(struct sk_buff *skb, int f) */ static inline void *skb_frag_address(const skb_frag_t *frag) { + if (!skb_frag_page(frag)) + return NULL; + return page_address(skb_frag_page(frag)) + skb_frag_off(frag); } diff --git a/net/core/dev.c b/net/core/dev.c index bbea1b252529..765f4a995693 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3385,8 +3385,9 @@ static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) if (!(dev->features & NETIF_F_HIGHDMA)) { for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + struct page *page = skb_frag_page(frag); - if (PageHighMem(skb_frag_page(frag))) + if (page && PageHighMem(page)) return 1; } } diff --git a/net/core/gro.c b/net/core/gro.c index 0759277dc14e..42d7f6755f32 100644 --- a/net/core/gro.c +++ b/net/core/gro.c @@ -376,7 +376,7 @@ static inline void skb_gro_reset_offset(struct sk_buff *skb, u32 nhoff) NAPI_GRO_CB(skb)->frag0 = NULL; NAPI_GRO_CB(skb)->frag0_len = 0; - if (!skb_headlen(skb) && pinfo->nr_frags && + if (!skb_headlen(skb) && pinfo->nr_frags && skb_frag_page(frag0) && !PageHighMem(skb_frag_page(frag0)) && (!NET_IP_ALIGN || !((skb_frag_off(frag0) + nhoff) & 3))) { NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0); diff --git a/net/core/skbuff.c b/net/core/skbuff.c index cf23392e97f5..907fff2894d3 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1378,6 +1378,14 @@ void skb_dump(const char *level, const struct sk_buff *skb, bool full_pkt) struct page *p; u8 *vaddr; + if (skb_frag_is_net_iov(frag)) { + printk("%sskb frag %d: not readable\n", level, i); + len -= frag->bv_len; + if (!len) + break; + continue; + } + skb_frag_foreach_page(frag, skb_frag_off(frag), skb_frag_size(frag), p, p_off, p_len, copied) { @@ -3145,6 +3153,9 @@ static bool __skb_splice_bits(struct sk_buff *skb, struct pipe_inode_info *pipe, for (seg = 0; seg < skb_shinfo(skb)->nr_frags; seg++) { const skb_frag_t *f = &skb_shinfo(skb)->frags[seg]; + if (WARN_ON_ONCE(!skb_frag_page(f))) + return false; + if (__splice_segment(skb_frag_page(f), skb_frag_off(f), skb_frag_size(f), offset, len, spd, false, sk, pipe)) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index c82dc42f57c6..51a5d263e8b4 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2166,6 +2166,9 @@ static int tcp_zerocopy_receive(struct sock *sk, break; } page = skb_frag_page(frags); + if (WARN_ON_ONCE(!page)) + break; + prefetchw(page); pages[pages_to_map++] = page; length += PAGE_SIZE;