From nobody Sat Nov 30 10:41:56 2024 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 8C1A518EFF8 for ; Tue, 10 Sep 2024 17:15:23 +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=1725988529; cv=none; b=OMBVv6WL3Tmfkd9I7p5IhOg2eipdLNZMu76UmECFqDqrjlf2tSOso6TWEkcjj7QTX7Dp+ophMks4468i9I7ME4qVcztxlezuabNGzFqkNOc8JTy7EBL1Xn71s7vsVupfm/5LRMBJ0ruiNnG84iqQp59uSeJUrOobzHtSawv1+t0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725988529; c=relaxed/simple; bh=uVANEC5Io/NBdef1ZHkEsM6uDVS7RL3aSO8YXYl8PEQ=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=UreIAKVFnanjXUTQogTyubxXRPV3/0x0LdmYGag+hqy9yOSEE7JLGXzqpsxgxysHDN5udU8Jhjj1PPWBGW9Xw4VQY/F0VVGyIi9Copy2tk6NAfqHNdZAKyup4/gWTCU/iqop7hntE7VamY6anWsFgdJFbj/5gZfrfsdw1/5AHF0= 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=Pg6sIi3e; 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="Pg6sIi3e" Received: by mail-yw1-f202.google.com with SMTP id 00721157ae682-6d683cfa528so22918557b3.0 for ; Tue, 10 Sep 2024 10:15:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1725988520; x=1726593320; 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=sdOXB2LFY1U7Whl+dw/pp7B7g7zmM9tRRPBgefo/nXc=; b=Pg6sIi3eeDXhNDgGaYd3o0asAVtPW5rwjxYiR3jyYDBIJXC3t6S9Kgun1lL8yy0aCl httDxmak4TF2xa1ks83wtVnnjCl3Qo5M4DMBYw2sy2XGrtwZDtqfSP93lJxebDv93kH4 iFufgCt9y4lBMCl4/z9hrymm2/geBexTYHCNPTgq/yjkC9MKlXWJBykaD7OWOm468QjW BSoWzCOFuX5nUFz7LMyy9PmLvb8w0hUv2Z5w1zvnjFA2nZgMXVJKqvA6dpULwlysEQo/ RKGOhm4lnKN6DxWDnX6iJqDGTKDfDrVGKhPUXvA0jV8uurvlwF4JYSHDJUcn72qEpclo Q4AA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1725988520; x=1726593320; 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=sdOXB2LFY1U7Whl+dw/pp7B7g7zmM9tRRPBgefo/nXc=; b=RqgdgO/7cLA0fKmZLxrIOLTnBfZGfRXXqJR37EQVRmfU/RG8qP8edYH1k7Er/xa4Xi YlYsKBJHcGU+NiA9xvh5YnoGz+vudB/867eOzBidgqFs78sW/mbGVjvmArmASgv7Y7Nu 8Yg5EVk70T1fcJSttuFBN5toMtiFQtSpp5lXsLfjYAaQbOyZlTdIt/DugSNTHt3ll4xV GUyQ05pykQeV8O3+EFJhQKd5cJEA+op/0PpNL6hhUVbTU4rlLTRKPVdghXkIDFqR4Omc kBGiNR+Vnlokaf5gzr9mMDvvE97HdXSI+YVOf6I6kuY05WdDW5IKzlGZU8FxuQynGB4w xdGw== X-Forwarded-Encrypted: i=1; AJvYcCXqahLmYcuHa61NGMc2u4rYSI+sdp2IrE6I/upEPyPKth6Qva0jMv5YOE53HXRyl2AHiutzf26DKMGNnpw=@vger.kernel.org X-Gm-Message-State: AOJu0Yy47JpByF+0NgC/wSHCtUSFbJ9OatatC2349yn6u9L+kC4hJ9H2 CHMrfBFvYdYngTmAz46aStlHMo05qXoYVeHjd4oOIhNDNGHiy959nsxhBlszQ97YzQyFfcCZQ8o 8XeJR2zbKtd4FEBbuWvz8DA== X-Google-Smtp-Source: AGHT+IGOCfxtxOEWkMf6F1XW1Cpo/N+WlxqPoBDoDrv4Oan+6cn72iQeLi0hRvSk31B40joXaJvdcGVXnQI0nNrQPA== X-Received: from almasrymina.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:4bc5]) (user=almasrymina job=sendgmr) by 2002:a05:690c:f8b:b0:69a:536:afde with SMTP id 00721157ae682-6dba6e1440bmr59027b3.5.1725988519740; Tue, 10 Sep 2024 10:15:19 -0700 (PDT) Date: Tue, 10 Sep 2024 17:14:54 +0000 In-Reply-To: <20240910171458.219195-1-almasrymina@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240910171458.219195-1-almasrymina@google.com> X-Mailer: git-send-email 2.46.0.598.g6f2099f65c-goog Message-ID: <20240910171458.219195-11-almasrymina@google.com> Subject: [PATCH net-next v26 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?q?Bj=C3=B6rn=20T=C3=B6pel?=" , Magnus Karlsson , Maciej Fijalkowski , Jonathan Lemon , Shuah Khan , Alexei Starovoitov , Daniel Borkmann , John Fastabend , Sumit Semwal , "=?UTF-8?q?Christian=20K=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 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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 | 5 ++ net/core/sock.c | 68 +++++++++++++++++++++++++++ 7 files changed, 78 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 =20 #if !defined(__KERNEL__) =20 diff --git a/arch/mips/include/uapi/asm/socket.h b/arch/mips/include/uapi/a= sm/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 =20 #if !defined(__KERNEL__) =20 diff --git a/arch/parisc/include/uapi/asm/socket.h b/arch/parisc/include/ua= pi/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 =20 #if !defined(__KERNEL__) =20 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 =20 #if !defined(__KERNEL__) =20 diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/s= ocket.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 =20 #if !defined(__KERNEL__) =20 diff --git a/include/uapi/linux/uio.h b/include/uapi/linux/uio.h index 3a22ddae376a..649739e0c404 100644 --- a/include/uapi/linux/uio.h +++ b/include/uapi/linux/uio.h @@ -33,6 +33,11 @@ struct dmabuf_cmsg { */ }; =20 +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; } =20 +#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 optle= n) +{ + unsigned int num_tokens, i, j, k, netmem_num =3D 0; + struct dmabuf_token *tokens; + netmem_ref netmems[16]; + int ret =3D 0; + + if (!sk_is_tcp(sk)) + return -EBADF; + + if (optlen % sizeof(struct dmabuf_token) || + optlen > sizeof(*tokens) * MAX_DONTNEED_TOKENS) + return -EINVAL; + + tokens =3D kvmalloc_array(optlen, sizeof(*tokens), GFP_KERNEL); + if (!tokens) + return -ENOMEM; + + num_tokens =3D 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 =3D 0; i < num_tokens; i++) { + for (j =3D 0; j < tokens[i].token_count; j++) { + netmem_ref netmem =3D (__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++] =3D netmem; + if (netmem_num =3D=3D ARRAY_SIZE(netmems)) { + xa_unlock_bh(&sk->sk_user_frags); + for (k =3D 0; k < netmem_num; k++) + WARN_ON_ONCE(!napi_pp_put_page(netmems[k])); + netmem_num =3D 0; + xa_lock_bh(&sk->sk_user_frags); + } + ret++; + } + } + } + + xa_unlock_bh(&sk->sk_user_frags); + for (k =3D 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 op= tname, ret =3D -EOPNOTSUPP; return ret; } +#ifdef CONFIG_PAGE_POOL + case SO_DEVMEM_DONTNEED: + return sock_devmem_dontneed(sk, optval, optlen); +#endif } =20 sockopt_lock_sock(sk); --=20 2.46.0.598.g6f2099f65c-goog