From mboxrd@z Thu Jan 1 00:00:00 1970 From: Willem de Bruijn Subject: [PATCH net-next v3 04/13] sock: add SOCK_ZEROCOPY sockopt Date: Wed, 21 Jun 2017 17:18:07 -0400 Message-ID: <20170621211816.53837-5-willemdebruijn.kernel@gmail.com> References: <20170621211816.53837-1-willemdebruijn.kernel@gmail.com> Return-path: In-Reply-To: <20170621211816.53837-1-willemdebruijn.kernel@gmail.com> Sender: netdev-owner@vger.kernel.org To: netdev@vger.kernel.org Cc: davem@davemloft.net, linux-api@vger.kernel.org, Willem de Bruijn List-Id: linux-api@vger.kernel.org From: Willem de Bruijn The send call ignores unknown flags. Legacy applications may already unwittingly pass MSG_ZEROCOPY. Continue to ignore this flag unless a socket opts in to zerocopy. Introduce socket option SO_ZEROCOPY to enable MSG_ZEROCOPY processing. Processes can also query this socket option to detect kernel support for the feature. Older kernels will return ENOPROTOOPT. Signed-off-by: Willem de Bruijn --- arch/alpha/include/uapi/asm/socket.h | 2 ++ arch/frv/include/uapi/asm/socket.h | 2 ++ arch/ia64/include/uapi/asm/socket.h | 2 ++ arch/m32r/include/uapi/asm/socket.h | 2 ++ arch/mips/include/uapi/asm/socket.h | 2 ++ arch/mn10300/include/uapi/asm/socket.h | 2 ++ arch/parisc/include/uapi/asm/socket.h | 2 ++ arch/s390/include/uapi/asm/socket.h | 2 ++ arch/sparc/include/uapi/asm/socket.h | 2 ++ arch/xtensa/include/uapi/asm/socket.h | 2 ++ include/uapi/asm-generic/socket.h | 2 ++ net/core/skbuff.c | 3 +++ net/core/sock.c | 14 ++++++++++++++ 13 files changed, 39 insertions(+) diff --git a/arch/alpha/include/uapi/asm/socket.h b/arch/alpha/include/uapi/asm/socket.h index 7b285dd4fe05..c6133a045352 100644 --- a/arch/alpha/include/uapi/asm/socket.h +++ b/arch/alpha/include/uapi/asm/socket.h @@ -109,4 +109,6 @@ #define SO_PEERGROUPS 59 +#define SO_ZEROCOPY 60 + #endif /* _UAPI_ASM_SOCKET_H */ diff --git a/arch/frv/include/uapi/asm/socket.h b/arch/frv/include/uapi/asm/socket.h index f1e3b20dce9f..9abf02d6855a 100644 --- a/arch/frv/include/uapi/asm/socket.h +++ b/arch/frv/include/uapi/asm/socket.h @@ -102,5 +102,7 @@ #define SO_PEERGROUPS 59 +#define SO_ZEROCOPY 60 + #endif /* _ASM_SOCKET_H */ diff --git a/arch/ia64/include/uapi/asm/socket.h b/arch/ia64/include/uapi/asm/socket.h index 5dd5c5d0d642..002eb85a6941 100644 --- a/arch/ia64/include/uapi/asm/socket.h +++ b/arch/ia64/include/uapi/asm/socket.h @@ -111,4 +111,6 @@ #define SO_PEERGROUPS 59 +#define SO_ZEROCOPY 60 + #endif /* _ASM_IA64_SOCKET_H */ diff --git a/arch/m32r/include/uapi/asm/socket.h b/arch/m32r/include/uapi/asm/socket.h index f8f7b47e247f..e268e51a38d1 100644 --- a/arch/m32r/include/uapi/asm/socket.h +++ b/arch/m32r/include/uapi/asm/socket.h @@ -102,4 +102,6 @@ #define SO_PEERGROUPS 59 +#define SO_ZEROCOPY 60 + #endif /* _ASM_M32R_SOCKET_H */ diff --git a/arch/mips/include/uapi/asm/socket.h b/arch/mips/include/uapi/asm/socket.h index 882823bec153..6c755bc07975 100644 --- a/arch/mips/include/uapi/asm/socket.h +++ b/arch/mips/include/uapi/asm/socket.h @@ -120,4 +120,6 @@ #define SO_PEERGROUPS 59 +#define SO_ZEROCOPY 60 + #endif /* _UAPI_ASM_SOCKET_H */ diff --git a/arch/mn10300/include/uapi/asm/socket.h b/arch/mn10300/include/uapi/asm/socket.h index c710db354ff2..ac82a3f26dbf 100644 --- a/arch/mn10300/include/uapi/asm/socket.h +++ b/arch/mn10300/include/uapi/asm/socket.h @@ -102,4 +102,6 @@ #define SO_PEERGROUPS 59 +#define SO_ZEROCOPY 60 + #endif /* _ASM_SOCKET_H */ diff --git a/arch/parisc/include/uapi/asm/socket.h b/arch/parisc/include/uapi/asm/socket.h index a0d4dc9f4eb2..3b2bf7ae703b 100644 --- a/arch/parisc/include/uapi/asm/socket.h +++ b/arch/parisc/include/uapi/asm/socket.h @@ -101,4 +101,6 @@ #define SO_PEERGROUPS 0x4034 +#define SO_ZEROCOPY 0x4035 + #endif /* _UAPI_ASM_SOCKET_H */ diff --git a/arch/s390/include/uapi/asm/socket.h b/arch/s390/include/uapi/asm/socket.h index 52a63f4175cb..a56916c83565 100644 --- a/arch/s390/include/uapi/asm/socket.h +++ b/arch/s390/include/uapi/asm/socket.h @@ -108,4 +108,6 @@ #define SO_PEERGROUPS 59 +#define SO_ZEROCOPY 60 + #endif /* _ASM_SOCKET_H */ diff --git a/arch/sparc/include/uapi/asm/socket.h b/arch/sparc/include/uapi/asm/socket.h index 186fd8199f54..b2f5c50d0947 100644 --- a/arch/sparc/include/uapi/asm/socket.h +++ b/arch/sparc/include/uapi/asm/socket.h @@ -98,6 +98,8 @@ #define SO_PEERGROUPS 0x003d +#define SO_ZEROCOPY 0x003e + /* Security levels - as per NRL IPv6 - don't actually do anything */ #define SO_SECURITY_AUTHENTICATION 0x5001 #define SO_SECURITY_ENCRYPTION_TRANSPORT 0x5002 diff --git a/arch/xtensa/include/uapi/asm/socket.h b/arch/xtensa/include/uapi/asm/socket.h index 3eed2761c149..220059999e74 100644 --- a/arch/xtensa/include/uapi/asm/socket.h +++ b/arch/xtensa/include/uapi/asm/socket.h @@ -113,4 +113,6 @@ #define SO_PEERGROUPS 59 +#define SO_ZEROCOPY 60 + #endif /* _XTENSA_SOCKET_H */ diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h index 9861be8da65e..e47c9e436221 100644 --- a/include/uapi/asm-generic/socket.h +++ b/include/uapi/asm-generic/socket.h @@ -104,4 +104,6 @@ #define SO_PEERGROUPS 59 +#define SO_ZEROCOPY 60 + #endif /* __ASM_GENERIC_SOCKET_H */ diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 31e31185c557..34fa1f2b7ff2 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -948,6 +948,9 @@ struct ubuf_info *sock_zerocopy_alloc(struct sock *sk, size_t size) WARN_ON_ONCE(!in_task()); + if (!sock_flag(sk, SOCK_ZEROCOPY)) + return NULL; + skb = sock_omalloc(sk, 0, GFP_KERNEL); if (!skb) return NULL; diff --git a/net/core/sock.c b/net/core/sock.c index 2822d30f2ad2..14f317d9a2bb 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1055,6 +1055,16 @@ int sock_setsockopt(struct socket *sock, int level, int optname, if (val == 1) dst_negative_advice(sk); break; + + case SO_ZEROCOPY: + if (sk->sk_state != TCP_CLOSE) + ret = -EBUSY; + else if (val < 0 || val > 1) + ret = -EINVAL; + else + sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool); + break; + default: ret = -ENOPROTOOPT; break; @@ -1383,6 +1393,10 @@ int sock_getsockopt(struct socket *sock, int level, int optname, v.val64 = sock_gen_cookie(sk); break; + case SO_ZEROCOPY: + v.val = sock_flag(sk, SOCK_ZEROCOPY); + break; + default: /* We implement the SO_SNDLOWAT etc to not be settable * (1003.1g 7). -- 2.13.1.611.g7e3b11ae1-goog