From patchwork Mon Nov 6 02:44:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mina Almasry X-Patchwork-Id: 13446237 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 54A91C4167B for ; Mon, 6 Nov 2023 02:45:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230231AbjKFCpT (ORCPT ); Sun, 5 Nov 2023 21:45:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41380 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230346AbjKFCo4 (ORCPT ); Sun, 5 Nov 2023 21:44:56 -0500 Received: from mail-yw1-x114a.google.com (mail-yw1-x114a.google.com [IPv6:2607:f8b0:4864:20::114a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 37A2ED7A for ; Sun, 5 Nov 2023 18:44:37 -0800 (PST) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-5b0e9c78309so53948447b3.1 for ; Sun, 05 Nov 2023 18:44:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1699238676; x=1699843476; 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=bbXy+8EI8/reBuw9EZooMZJzNkS3vxkh8+4Xq7ifx6w=; b=QGXMY136SJv8X/CLUqR1CFMrKd0RapdsEmr1qELFYNhEOgXjCagvWEVmBcmV7ofhrR KHCu3F+bneF1FArMXc0ACK4cwILfBYi0KP0SWDvQhOuQc3mcsxdASuD3Sq20PRDTQ2dR ByZLXG6Cubc25v9QZC0LVUV7xQKT81kml329mEvib+zbkNSpKA23zdIafExJiVFwV9uB GqG+hLcxdipbKBRfcQr82h2ep2/HsiV/oB0C/4l6KH9XSf1nxiA4ep4kGEd6P4cM9xYx yEAdXko1q+gfSSZpKJr0PWSgIhEewWbB+zsy5iBoMUANzILRzEGyVtaOweVlUcpy96lC qWlw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1699238676; x=1699843476; 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=bbXy+8EI8/reBuw9EZooMZJzNkS3vxkh8+4Xq7ifx6w=; b=bM4FEIhvsM0fP/g4e1z7be91+J94NeDk9pexA/Ju/T31+Mutmrsihf4TRhhQHo9a7M mgN9Ox37L2ba+wlBs4EHAV6MzDYy74HZHCPxdJqj7yqtfe2VMt20mLM1PGzyTKhe569b TuH26CyafQO4tREqGrH4igxr0OuGi2CXxeoHS5dYnGjYY2lf3M+bcSFWW26EAkF1BLAI YmxiPUBBHSN+63shtdUsqwdRrjnG6wXe9nLt4SYDeXkKmgdmr1839MDLZTf8ZLoqTmnm K68ocsL/8pk0NDUUp9hc31XzHwqol6AT56Bvfsy1uQo8+heY15husHUO4IN/EgVs2Vrr 8UgQ== X-Gm-Message-State: AOJu0Yxmy+xKXz4AxlIfmAf5ZrWh6Kaz1dPgNF8R9gYpNZLTk1DIJ1DQ 2TIjxP+D/6Z5gwDzSJSQaU/fpIEhQaI61h2t5g== X-Google-Smtp-Source: AGHT+IGWdWv+ANGYqQyzA2UyXJhi775o4ifiKnH6NXK6tcVAsYvHc+4YYt6Jkb55wfo8xTcaVhvPEUirYwS2JNQH1Q== X-Received: from almasrymina.svl.corp.google.com ([2620:15c:2c4:200:35de:fff:97b7:db3e]) (user=almasrymina job=sendgmr) by 2002:a81:92ce:0:b0:59e:ee51:52a1 with SMTP id j197-20020a8192ce000000b0059eee5152a1mr195351ywg.10.1699238675828; Sun, 05 Nov 2023 18:44:35 -0800 (PST) Date: Sun, 5 Nov 2023 18:44:07 -0800 In-Reply-To: <20231106024413.2801438-1-almasrymina@google.com> Mime-Version: 1.0 References: <20231106024413.2801438-1-almasrymina@google.com> X-Mailer: git-send-email 2.42.0.869.gea05f2083d-goog Message-ID: <20231106024413.2801438-9-almasrymina@google.com> Subject: [RFC PATCH v3 08/12] net: support non paged skb frags From: Mina Almasry To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org Cc: Mina Almasry , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Jesper Dangaard Brouer , Ilias Apalodimas , Arnd Bergmann , David Ahern , Willem de Bruijn , Shuah Khan , Sumit Semwal , " =?utf-8?q?Christian_K=C3=B6nig?= " , Shakeel Butt , Jeroen de Borst , Praveen Kaligineedi Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Make skb_frag_page() fail in the case where the frag is not backed by a page, and fix its relevent callers to handle this case. Correctly handle skb_frag refcounting in the page_pool_iovs case. Signed-off-by: Mina Almasry --- include/linux/skbuff.h | 42 +++++++++++++++++++++++++++++++++++------- net/core/gro.c | 2 +- net/core/skbuff.c | 3 +++ net/ipv4/tcp.c | 10 +++++++++- 4 files changed, 48 insertions(+), 9 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 97bfef071255..1fae276c1353 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -37,6 +37,8 @@ #endif #include #include +#include +#include /** * DOC: skb checksums @@ -3402,15 +3404,38 @@ static inline void skb_frag_off_copy(skb_frag_t *fragto, fragto->bv_offset = fragfrom->bv_offset; } +/* Returns true if the skb_frag contains a page_pool_iov. */ +static inline bool skb_frag_is_page_pool_iov(const skb_frag_t *frag) +{ + return page_is_page_pool_iov(frag->bv_page); +} + /** * 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) { - return frag->bv_page; + if (!page_is_page_pool_iov(frag->bv_page)) + return frag->bv_page; + + return NULL; +} + +/** + * skb_frag_page_pool_iov - retrieve the page_pool_iov referred to by fragment + * @frag: the fragment + * + * Returns the &struct page_pool_iov associated with @frag. Returns NULL if this + * frag has no associated page_pool_iov. + */ +static inline struct page_pool_iov * +skb_frag_page_pool_iov(const skb_frag_t *frag) +{ + return page_to_page_pool_iov(frag->bv_page); } /** @@ -3421,7 +3446,7 @@ static inline struct page *skb_frag_page(const skb_frag_t *frag) */ static inline void __skb_frag_ref(skb_frag_t *frag) { - get_page(skb_frag_page(frag)); + page_pool_page_get_many(frag->bv_page, 1); } /** @@ -3441,13 +3466,13 @@ bool napi_pp_put_page(struct page *page, 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, napi_safe)) + if (recycle && napi_pp_put_page(frag->bv_page, napi_safe)) return; + page_pool_page_put_many(frag->bv_page, 1); +#else + put_page(skb_frag_page(frag)); #endif - put_page(page); } /** @@ -3487,6 +3512,9 @@ 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/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 c52ddd6891d9..13eca4fd25e1 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2994,6 +2994,9 @@ 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 a86d8200a1e8..23b29dc49271 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2155,6 +2155,9 @@ 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; @@ -4411,7 +4414,12 @@ int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *hp, for (i = 0; i < shi->nr_frags; ++i) { const skb_frag_t *f = &shi->frags[i]; unsigned int offset = skb_frag_off(f); - struct page *page = skb_frag_page(f) + (offset >> PAGE_SHIFT); + struct page *page = skb_frag_page(f); + + if (WARN_ON_ONCE(!page)) + return 1; + + page += offset >> PAGE_SHIFT; sg_set_page(&sg, page, skb_frag_size(f), offset_in_page(offset));