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: 13581524 Received: from mail-yw1-f202.google.com (mail-yw1-f202.google.com [209.85.128.202]) (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 A56EC43ABD for ; Tue, 5 Mar 2024 02:02:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709604145; cv=none; b=q+T4v/p7XvJY1xPvf5zYS4aH3z1KKN8w2mzlCmbMII7u8uj8u9VrDUb0d0QuZTIlFp5aGMC6BMH15IbuJxjhso/91ouC0De7N/zQztBgTza4fDeB/9KBUn6QZAeSvtzWfVy7bdK6c5vlDdocQSLViXB1NeH7uqVOfgVLidEOoZk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709604145; c=relaxed/simple; bh=ZkKDRjbXOJaCgdsUUhVdqCPuQ0SfWJoIIrbbmmGQ/FE=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=Beh5uLq691JiSIw9FtkTxwOpv2D+JTRxWe+aRlRpXZ9EJgiXbsccg9JMFafR//GOHhjmhncGgtdFrtHm3yQLkuKMZ2aIRHihDrAUX600YJmDulikCsl250NyxKo59lFgsf891FXkboflD4aquR1OrAbR92uUrW9SS6zT4zzIFFM= 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=WLoWZiZp; arc=none smtp.client-ip=209.85.128.202 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="WLoWZiZp" Received: by mail-yw1-f202.google.com with SMTP id 00721157ae682-5f38d676cecso80456777b3.0 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=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=kFOLH8z6Kc1/DHNjJCRtctXlk4wkt0G4E5LxaUbD2lM=; b=WLoWZiZpUGPt4dSD7lzG4aIwzfZFDrSu2b9dCRJI0s0vPx1F/4kssBhpB/fm7J5vM4 YGrzYu5FikmZpB/QM6HH8/roiaA3J/zaE9kbJwyib2Esv/gG7G2EtE0pvOSIMvYeuDZn cE1g0GZkmVTpkpY4ktpZPtuiBap6M6ChGB/G6zxyhq70o1sNFr7v8o/Xl7J2tkFosklJ rKP2Nx/+5+Wnc9JCAiPP09YRZa8EqY1HSxlr8Zjs9ut3WndncFAvAlNd38BuRBcZLcS7 KQ0OXjzG1WV6nuXHeVo62EjW9ffcoue8rRspAYYPDJJyqltH3qGHhZwD7pRWVqn4GHfm bP7g== 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=JcN30F7M29F15tiwZUowaWg6R02XtC+I5I7i9cCpPDYlUj2X21AfW0SjudAbJaU9bU JTWNCQMufeTbK/hnovXCFI4svbLpSopn812kRDJYOJoYvvNofZI+8050LvYKP4pypplr BHv8QnkBXCmuPnDlCxrW8FtfjfZTNfXfE9gmkxPg5iCVe1/0Hl+W4SwLOU+X9sRdrR9s RbPvfNvEl/A7u9ZUf00Zqe+wK22YnotrjaUPu0ksEfKwdBCJCQTYdcjypv/SSW/N+UK9 M/NgHHj2b7DjJpSe2/Nxb1oUPNv5tePK6yO55eTHoEXn97ZO7hRfihLq7OD75UhVknkF 2BXw== X-Forwarded-Encrypted: i=1; AJvYcCWZTj1nQi7Ci2VPcGBXdfljfQPfoyvhR+6VdlSVonzpDTAZixPJZvyQlU2p/M9DPmUm/jBUBXlyaebTeHg/APW7vZo/tR0ww9Z160Y= X-Gm-Message-State: AOJu0YyQRwJ10ZXKj47KTsSmOU9V71sZ+QXEHMsXRqYsZJvNBLAElxBB 4ybQ3cEU/gQSqUuUUZxV1Kq3JMJjKujpB5RSaWYfltm/FUrAup2nn4rytN/o+4Kfod7cYvE84O1 l8srO6VwxAkM2fOvxel3qSw== 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> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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 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;