From patchwork Thu Aug 29 06:01:23 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mina Almasry X-Patchwork-Id: 13782492 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 D246014F9DD for ; Thu, 29 Aug 2024 06:01:56 +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=1724911321; cv=none; b=dqVSGc7KaBKnFVmy5GfnOUj0fYdQ73GgcyUDPZ983PMYFfHRymWtxlLOgyTS4E8Wr3YUbbjd18OT4JVmoknEEjLN09QZzulTeeX17EkNlvuZ7GArUzP5M40t6t8IoNypt+zAhsk0G/sbT89VDgycVlq1uAniDcT/XhJiXB7onOw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724911321; c=relaxed/simple; bh=y493pBuMuXtKSS1nHc/d3DLVMXqmDAj6y5DRsbVmyGQ=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=kSNQW4NdCUTBfuX75dDtXiU2ZQq+Qyi7z+JPna7CSHOeGKenF2tz8qV9zYB+PUS6+1yJNdiY6zYGk6ST/VZryvkqb+y4XDY4Om6yTzMajV2n+tbaMD15hcsV5V+A1nQ8SnBy/Nveb6xxcNdv667lrlpZ3TTAxIxhffmDHhULM8c= 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=fb/9Wcm7; 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="fb/9Wcm7" Received: by mail-yw1-f201.google.com with SMTP id 00721157ae682-6b71aa9349dso6703777b3.1 for ; Wed, 28 Aug 2024 23:01:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1724911314; x=1725516114; 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=39H1hvAt4oUXephuqAsRMNiSS8rVQOUnNeObWUoRUdg=; b=fb/9Wcm7+pRKRnIkGeJ/8za+X475QA4/nSwblAc6VOXDP8pQvo+b2ApWi/JsJqWHp9 c7/tr7B5Vj/1cpA7a47wnS++qj+MJ0LyF50sS0tv5X2j9ndu5u1DvUXj3Pp1zsnl9tV/ Dwb2XxHg+3Kbr0wyruSGl7YwOtpSFTjXJWtq2MDsImlhzmgjBOeSW8XCnvpvNBuamf2W j9/BDrIFqJcBhKl3WiF09+nuACWBq1Bn9HhFIwgUR7NkrdRephWTGeT1kjPyt1GPWE08 8pyUaDtZ1ciQsGSUhsJLZVOZ6aHmyZRCbuE2PW3CwkEkwnodd2XVYeqWVKhEuPQ5Ez3b t6Gw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724911314; x=1725516114; 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=39H1hvAt4oUXephuqAsRMNiSS8rVQOUnNeObWUoRUdg=; b=Q6RVQdr0ALVsXA0bIJiSsYMtoq4qax6g0XUpy+LHJIuU2A7KUUtl9RHiupt6tXOTd8 jtj16tEOeLY3uMJbB1FBF8/Cy6+51XPiQErfTSaDIwuYByihw8wN2HcNjRx1c8HlW8Zk BZR2cE4v5w98xcimH17bQky5gc+zTEFCnJZ1rEVT8r5ZoeyfZj3PEq1dU+yZrKwefH96 nGcxASNEl8iWZzqodhQC5CzFRhnGA8e2zmqeKAFJkEvjyeTA6igeCTNtBMcF9VH22ZEN gePnXknRhPWbRowHLtkOKiLF++okCcF/r2V9keNbimJibEHc9BzNTSE6sxBBv1f8rRjo 6ttw== X-Forwarded-Encrypted: i=1; AJvYcCUosXmEEPT7AhCtbaAE56rY7/LhntjFbWO4o6x+sfXKiKTV3MV0UnfcAVGRu8XJhT6n17s=@vger.kernel.org X-Gm-Message-State: AOJu0Yx/pwganLJ/kjGrYk8RntM2jwihTxU9twLH0xk9przSIIj0JIYv 48uRyZu2ncBU1Babswr3oO4U6aPTpIHI5bWni0HeNpy9gJj5l2uFE1eFejKw4WHkteAJfn/NZER vxESkt2uYeExPD/ExxT71Yg== X-Google-Smtp-Source: AGHT+IFlKxfYJtUYdI/TRRsslXH4R/J8NhGJjCzi/u/iQQ0T5OjcHHDfMxK7jHNcKc54AyL4IIKcY8/TGe6lhKctAg== X-Received: from almasrymina.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:4bc5]) (user=almasrymina job=sendgmr) by 2002:a25:9ac6:0:b0:e11:7105:956a with SMTP id 3f1490d57ef6-e1a5ab4519fmr2841276.3.1724911314303; Wed, 28 Aug 2024 23:01:54 -0700 (PDT) Date: Thu, 29 Aug 2024 06:01:23 +0000 In-Reply-To: <20240829060126.2792671-1-almasrymina@google.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240829060126.2792671-1-almasrymina@google.com> X-Mailer: git-send-email 2.46.0.469.g59c65b2a67-goog Message-ID: <20240829060126.2792671-11-almasrymina@google.com> Subject: [PATCH net-next v23 10/13] net: add SO_DEVMEM_DONTNEED setsockopt to release RX 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 , 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 , " =?utf-8?b?QmrDtnJu?= =?utf-8?b?IFTDtnBlbA==?= " , Magnus Karlsson , Maciej Fijalkowski , Jonathan Lemon , Shuah Khan , Alexei Starovoitov , Daniel Borkmann , John Fastabend , 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 , Bagas Sanjaya , Christoph Hellwig , Nikolay Aleksandrov , Taehee Yoo , Willem de Bruijn , Kaiyuan Zhang X-Patchwork-Delegate: kuba@kernel.org Add an interface for the user to notify the kernel that it is done reading the devmem dmabuf frags returned as cmsg. The kernel will drop the reference on the frags to make them available for reuse. Signed-off-by: Willem de Bruijn Signed-off-by: Kaiyuan Zhang Signed-off-by: Mina Almasry Reviewed-by: Pavel Begunkov Reviewed-by: Eric Dumazet --- v16: - Use sk_is_tcp(). - Fix unnamed 128 DONTNEED limit (David). - Fix kernel allocating for 128 tokens even if the user didn't ask for that much (Eric). - Fix number assignement (Arnd). v10: - Fix leak of tokens (Nikolay). v7: - Updated SO_DEVMEM_* uapi to use the next available entry (Arnd). v6: - Squash in locking optimizations from edumazet@google.com. With his changes we lock the xarray once per sock_devmem_dontneed operation rather than once per frag. Changes in v1: - devmemtoken -> dmabuf_token (David). - Use napi_pp_put_page() for refcounting (Yunsheng). - Fix build error with missing socket options on other asms. --- arch/alpha/include/uapi/asm/socket.h | 1 + arch/mips/include/uapi/asm/socket.h | 1 + arch/parisc/include/uapi/asm/socket.h | 1 + arch/sparc/include/uapi/asm/socket.h | 1 + include/uapi/asm-generic/socket.h | 1 + include/uapi/linux/uio.h | 4 ++ net/core/sock.c | 68 +++++++++++++++++++++++++++ 7 files changed, 77 insertions(+) diff --git a/arch/alpha/include/uapi/asm/socket.h b/arch/alpha/include/uapi/asm/socket.h index ef4656a41058..251b73c5481e 100644 --- a/arch/alpha/include/uapi/asm/socket.h +++ b/arch/alpha/include/uapi/asm/socket.h @@ -144,6 +144,7 @@ #define SCM_DEVMEM_LINEAR SO_DEVMEM_LINEAR #define SO_DEVMEM_DMABUF 79 #define SCM_DEVMEM_DMABUF SO_DEVMEM_DMABUF +#define SO_DEVMEM_DONTNEED 80 #if !defined(__KERNEL__) diff --git a/arch/mips/include/uapi/asm/socket.h b/arch/mips/include/uapi/asm/socket.h index 414807d55e33..8ab7582291ab 100644 --- a/arch/mips/include/uapi/asm/socket.h +++ b/arch/mips/include/uapi/asm/socket.h @@ -155,6 +155,7 @@ #define SCM_DEVMEM_LINEAR SO_DEVMEM_LINEAR #define SO_DEVMEM_DMABUF 79 #define SCM_DEVMEM_DMABUF SO_DEVMEM_DMABUF +#define SO_DEVMEM_DONTNEED 80 #if !defined(__KERNEL__) diff --git a/arch/parisc/include/uapi/asm/socket.h b/arch/parisc/include/uapi/asm/socket.h index 2b817efd4544..38fc0b188e08 100644 --- a/arch/parisc/include/uapi/asm/socket.h +++ b/arch/parisc/include/uapi/asm/socket.h @@ -136,6 +136,7 @@ #define SCM_DEVMEM_LINEAR SO_DEVMEM_LINEAR #define SO_DEVMEM_DMABUF 79 #define SCM_DEVMEM_DMABUF SO_DEVMEM_DMABUF +#define SO_DEVMEM_DONTNEED 80 #if !defined(__KERNEL__) diff --git a/arch/sparc/include/uapi/asm/socket.h b/arch/sparc/include/uapi/asm/socket.h index 00248fc68977..57084ed2f3c4 100644 --- a/arch/sparc/include/uapi/asm/socket.h +++ b/arch/sparc/include/uapi/asm/socket.h @@ -137,6 +137,7 @@ #define SCM_DEVMEM_LINEAR SO_DEVMEM_LINEAR #define SO_DEVMEM_DMABUF 0x0058 #define SCM_DEVMEM_DMABUF SO_DEVMEM_DMABUF +#define SO_DEVMEM_DONTNEED 0x0059 #if !defined(__KERNEL__) diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h index e993edc9c0ee..3b4e3e815602 100644 --- a/include/uapi/asm-generic/socket.h +++ b/include/uapi/asm-generic/socket.h @@ -139,6 +139,7 @@ #define SCM_DEVMEM_LINEAR SO_DEVMEM_LINEAR #define SO_DEVMEM_DMABUF 79 #define SCM_DEVMEM_DMABUF SO_DEVMEM_DMABUF +#define SO_DEVMEM_DONTNEED 80 #if !defined(__KERNEL__) diff --git a/include/uapi/linux/uio.h b/include/uapi/linux/uio.h index 3a22ddae376a..d17f8fcd93ec 100644 --- a/include/uapi/linux/uio.h +++ b/include/uapi/linux/uio.h @@ -33,6 +33,10 @@ struct dmabuf_cmsg { */ }; +struct dmabuf_token { + __u32 token_start; + __u32 token_count; +}; /* * UIO_MAXIOV shall be at least 16 1003.1g (5.4.1.1) */ diff --git a/net/core/sock.c b/net/core/sock.c index 468b1239606c..bbb57b5af0b1 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -124,6 +124,7 @@ #include #include #include +#include #include #include #include @@ -1049,6 +1050,69 @@ static int sock_reserve_memory(struct sock *sk, int bytes) return 0; } +#ifdef CONFIG_PAGE_POOL + +/* This is the number of tokens that the user can SO_DEVMEM_DONTNEED in + * 1 syscall. The limit exists to limit the amount of memory the kernel + * allocates to copy these tokens. + */ +#define MAX_DONTNEED_TOKENS 128 + +static noinline_for_stack int +sock_devmem_dontneed(struct sock *sk, sockptr_t optval, unsigned int optlen) +{ + unsigned int num_tokens, i, j, k, netmem_num = 0; + struct dmabuf_token *tokens; + netmem_ref netmems[16]; + int ret = 0; + + if (!sk_is_tcp(sk)) + return -EBADF; + + if (optlen % sizeof(struct dmabuf_token) || + optlen > sizeof(*tokens) * MAX_DONTNEED_TOKENS) + return -EINVAL; + + tokens = kvmalloc_array(optlen, sizeof(*tokens), GFP_KERNEL); + if (!tokens) + return -ENOMEM; + + num_tokens = optlen / sizeof(struct dmabuf_token); + if (copy_from_sockptr(tokens, optval, optlen)) { + kvfree(tokens); + return -EFAULT; + } + + xa_lock_bh(&sk->sk_user_frags); + for (i = 0; i < num_tokens; i++) { + for (j = 0; j < tokens[i].token_count; j++) { + netmem_ref netmem = (__force netmem_ref)__xa_erase( + &sk->sk_user_frags, tokens[i].token_start + j); + + if (netmem && + !WARN_ON_ONCE(!netmem_is_net_iov(netmem))) { + netmems[netmem_num++] = netmem; + if (netmem_num == ARRAY_SIZE(netmems)) { + xa_unlock_bh(&sk->sk_user_frags); + for (k = 0; k < netmem_num; k++) + WARN_ON_ONCE(!napi_pp_put_page(netmems[k])); + netmem_num = 0; + xa_lock_bh(&sk->sk_user_frags); + } + ret++; + } + } + } + + xa_unlock_bh(&sk->sk_user_frags); + for (k = 0; k < netmem_num; k++) + WARN_ON_ONCE(!napi_pp_put_page(netmems[k])); + + kvfree(tokens); + return ret; +} +#endif + void sockopt_lock_sock(struct sock *sk) { /* When current->bpf_ctx is set, the setsockopt is called from @@ -1211,6 +1275,10 @@ int sk_setsockopt(struct sock *sk, int level, int optname, ret = -EOPNOTSUPP; return ret; } +#ifdef CONFIG_PAGE_POOL + case SO_DEVMEM_DONTNEED: + return sock_devmem_dontneed(sk, optval, optlen); +#endif } sockopt_lock_sock(sk);