From patchwork Mon Aug 19 03:54:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mina Almasry X-Patchwork-Id: 13767771 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-yw1-f201.google.com (mail-yw1-f201.google.com [209.85.128.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F317E13D60A for ; Mon, 19 Aug 2024 03:55:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724039710; cv=none; b=BA4p3GJs9hoaadDealiMJjIs4ghFNI7bYUhEiccHRuOsqeapN8IsH3zO52/pl0GPbjDyLoBnIHzLHzt5J4QN3YUMgMHOvumB6ty62gce/IucX84SOiJ5Vy2Y20kkZNYFheOnbahOvSp0+cw2/p4uXoATZaRu88lwuViqyQ6QjyM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724039710; c=relaxed/simple; bh=g87cnJEAEYQuJwIaCe/asckSp8mb/c9FiWNvn/kDzGk=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=U3MgZL35DasrlO4z5qFar/wpgrq40T5TmFXmeaDTkiTRVaFw6s34Zjt+M+EU3KG3kiGGIoKQebg6MRNs1LKkxRTeaGnEmL5O/gPjSe0K8Sv002g1hXvWhNuiRnbhvFxDOrqzNdreUihEZLi0ycQa8QP5OfzGGAPG8DRkoAfo6xw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=DP2+sonv; arc=none smtp.client-ip=209.85.128.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="DP2+sonv" Received: by mail-yw1-f201.google.com with SMTP id 00721157ae682-6b0f068833bso42352977b3.0 for ; Sun, 18 Aug 2024 20:55:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1724039703; x=1724644503; darn=vger.kernel.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=38N2mnCyB6NKtemrRM3mBvs8UHuNO1oUKPgmyDKBTvA=; b=DP2+sonvj586e+1Rqak2WYMZk43uprRFiWRjx+j0VoNFiBtf9B6QePwCiSA6RXG+7u Bi/0maOmDW8kH79K9C6zVdcC9UkaNdsto6S2X7UEvwsGPClUYh8nvsAxE3CIKXI2Qw8B lE68xKx6im0RaxBPhckfHB6dhcRlHNs41gKNhyU1lALSDpQVMmM6odgpYKWDAJKwR9Cs 4zeDGDvOGlZsj4vsoFyPpaIdQ5w7PlLwpI1sQJ8x3pXrozj5Lzxmr7q4hyYQgH/nQh9N O3uMUNdAXETqlIpA07uxt3r5gacSEgQhp+q5raPvhLt3RW0+X09XCTZAIxOVPwaRGESF hjrQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724039703; x=1724644503; 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=38N2mnCyB6NKtemrRM3mBvs8UHuNO1oUKPgmyDKBTvA=; b=wH9Or4U5JUVr0s+7JdapZWUeHOfzgCKdvb+02NHYq4gf1g3yWGDfcgvg69GARGHqsr H+C7PA3PT5ncFTv+TzGR5HP14r+gkZS5pho0tflBb1xuKb/6DNHEFEN1S85e5dWpfsen ND4iouSAfLtOo73LP+aJ5x+3iQ4PxPbnLbgi3nrqivh0Mk/UsOFKZkU4uCA/OukDO415 PcpGceTTg+8LtoaUe4zMlsP7tufaeSMO01poMF4qYDg+ThXMQ2nofWElWVzNF5QP7NiI QM+KOmq3rawlABQdGgdK9pMtSYL6TctzH7nLZAVXY2HmhQGyhs6PsVmSidMYYBzoQM4M FU/Q== X-Forwarded-Encrypted: i=1; AJvYcCWDSBnBluCpRB9h6sq2lEhNMgXdehKLa0UuGXOXTutcNbEGVbPZzHm1X8n2mA+dnKgbpa8TL5X+0e7lxqS6WNOxA04t X-Gm-Message-State: AOJu0YwCndNzQMKlaeSFWkIitA+dVWp6mzxMHr5GVMWGeDLXIjSSjVUr GZebkcx8avdgVCP7FKqyyERj24xL/mBzErf3UsiSzQ2Vu5JUiMs5FhQ1akle6WRW98YvTzoTT+L +zMulKRsSSqjEZPxmgWcOGw== X-Google-Smtp-Source: AGHT+IF6nvUUTpxgwJzge0iJGlbYECWQOzBk6M2HQZK0kJmLzNzfKYo94tilSvK+SUogeTQu0C3uytiioDSeBBjEZA== X-Received: from almasrymina.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:4bc5]) (user=almasrymina job=sendgmr) by 2002:a25:910e:0:b0:e0b:a34d:f223 with SMTP id 3f1490d57ef6-e116cecab95mr183108276.5.1724039702913; Sun, 18 Aug 2024 20:55:02 -0700 (PDT) Date: Mon, 19 Aug 2024 03:54:42 +0000 In-Reply-To: <20240819035448.2473195-1-almasrymina@google.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240819035448.2473195-1-almasrymina@google.com> X-Mailer: git-send-email 2.46.0.184.g6999bdac58-goog Message-ID: <20240819035448.2473195-8-almasrymina@google.com> Subject: [PATCH net-next v20 07/13] 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, linux-kselftest@vger.kernel.org, bpf@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 , Donald Hunter , 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 , Steffen Klassert , Herbert Xu , David Ahern , Willem de Bruijn , Shuah Khan , Alexei Starovoitov , Daniel Borkmann , John Fastabend , Sumit Semwal , " =?utf-8?q?Christian_K=C3=B6nig?= " , Bagas Sanjaya , Christoph Hellwig , Nikolay Aleksandrov , Taehee Yoo , Pavel Begunkov , David Wei , Jason Gunthorpe , Yunsheng Lin , Shailend Chand , Harshitha Ramamurthy , Shakeel Butt , Jeroen de Borst , Praveen Kaligineedi X-Patchwork-Delegate: kuba@kernel.org 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 Reviewed-by: Eric Dumazet --- v10: - Fixed newly generated kdoc warnings found by patchwork. While we're at it, fix the Return section of the functions I touched. 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 | 42 +++++++++++++++++++++++++++++++++++++- include/linux/skbuff_ref.h | 9 ++++---- net/core/dev.c | 3 ++- net/core/gro.c | 3 ++- net/core/skbuff.c | 11 ++++++++++ net/ipv4/esp4.c | 3 ++- net/ipv4/tcp.c | 3 +++ net/ipv6/esp6.c | 3 ++- 8 files changed, 67 insertions(+), 10 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index cf8f6ce06742..dbadf2dd6b35 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -3523,21 +3523,58 @@ static inline void skb_frag_off_copy(skb_frag_t *fragto, fragto->offset = fragfrom->offset; } +/* Return: 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 + * + * Return: 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. + * Return: 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 + * + * Return: the &netmem_ref associated with @frag. + */ +static inline netmem_ref skb_frag_netmem(const skb_frag_t *frag) +{ + return frag->netmem; +} + int skb_pp_cow_data(struct page_pool *pool, struct sk_buff **pskb, unsigned int headroom); int skb_cow_data_for_xdp(struct page_pool *pool, struct sk_buff **pskb, struct bpf_prog *prog); + /** * skb_frag_address - gets the address of the data contained in a paged fragment * @frag: the paged fragment buffer @@ -3547,6 +3584,9 @@ int skb_cow_data_for_xdp(struct page_pool *pool, struct sk_buff **pskb, */ 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/include/linux/skbuff_ref.h b/include/linux/skbuff_ref.h index 16c241a23472..0f3c58007488 100644 --- a/include/linux/skbuff_ref.h +++ b/include/linux/skbuff_ref.h @@ -34,14 +34,13 @@ static inline void skb_frag_ref(struct sk_buff *skb, int f) bool napi_pp_put_page(netmem_ref netmem); -static inline void -skb_page_unref(struct page *page, bool recycle) +static inline void skb_page_unref(netmem_ref netmem, bool recycle) { #ifdef CONFIG_PAGE_POOL - if (recycle && napi_pp_put_page(page_to_netmem(page))) + if (recycle && napi_pp_put_page(netmem)) return; #endif - put_page(page); + put_page(netmem_to_page(netmem)); } /** @@ -54,7 +53,7 @@ skb_page_unref(struct page *page, bool recycle) */ static inline void __skb_frag_unref(skb_frag_t *frag, bool recycle) { - skb_page_unref(skb_frag_page(frag), recycle); + skb_page_unref(skb_frag_netmem(frag), recycle); } /** diff --git a/net/core/dev.c b/net/core/dev.c index 019f86a3d614..f6f40c682b83 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3431,8 +3431,9 @@ 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 b3b43de1a650..26f09c3e830b 100644 --- a/net/core/gro.c +++ b/net/core/gro.c @@ -408,7 +408,8 @@ static inline void skb_gro_reset_offset(struct sk_buff *skb, u32 nhoff) pinfo = skb_shinfo(skb); frag0 = &pinfo->frags[0]; - if (pinfo->nr_frags && !PageHighMem(skb_frag_page(frag0)) && + if (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); NAPI_GRO_CB(skb)->frag0_len = min_t(unsigned int, diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 9e2b28342793..91c7def73700 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1371,6 +1371,14 @@ 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 -= skb_frag_size(frag); + if (!len) + break; + continue; + } + skb_frag_foreach_page(frag, skb_frag_off(frag), skb_frag_size(frag), p, p_off, p_len, copied) { @@ -3163,6 +3171,9 @@ 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/esp4.c b/net/ipv4/esp4.c index 47378ca41904..f3281312eb5e 100644 --- a/net/ipv4/esp4.c +++ b/net/ipv4/esp4.c @@ -115,7 +115,8 @@ static void esp_ssg_unref(struct xfrm_state *x, void *tmp, struct sk_buff *skb) */ if (req->src != req->dst) for (sg = sg_next(req->src); sg; sg = sg_next(sg)) - skb_page_unref(sg_page(sg), skb->pp_recycle); + skb_page_unref(page_to_netmem(sg_page(sg)), + skb->pp_recycle); } #ifdef CONFIG_INET_ESPINTCP diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 8514257f4ecd..20a1b0333017 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2177,6 +2177,9 @@ 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; diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c index 3920e8aa1031..b2400c226a32 100644 --- a/net/ipv6/esp6.c +++ b/net/ipv6/esp6.c @@ -132,7 +132,8 @@ static void esp_ssg_unref(struct xfrm_state *x, void *tmp, struct sk_buff *skb) */ if (req->src != req->dst) for (sg = sg_next(req->src); sg; sg = sg_next(sg)) - skb_page_unref(sg_page(sg), skb->pp_recycle); + skb_page_unref(page_to_netmem(sg_page(sg)), + skb->pp_recycle); } #ifdef CONFIG_INET6_ESPINTCP