From a02053c83c116bea59d18c638a40714d494f53a7 Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Tue, 21 Feb 2012 07:31:34 +0000 Subject: [PATCH] sock: Introduce the SO_PEEK_OFF sock option This one specifies where to start MSG_PEEK-ing queue data from. When set to negative value means that MSG_PEEK works as ususally -- peeks from the head of the queue always. When some bytes are peeked from queue and the peeking offset is non negative it is moved forward so that the next peek will return next portion of data. When non-peeking recvmsg occurs and the peeking offset is non negative is is moved backward so that the next peek will still peek the proper data (i.e. the one that would have been picked if there were no non peeking recv in between). The offset is set using per-proto opteration to let the protocol handle the locking issues and to check whether the peeking offset feature is supported by the protocol the socket belongs to. Signed-off-by: Pavel Emelyanov Signed-off-by: David S. Miller --- arch/alpha/include/asm/socket.h | 1 + arch/arm/include/asm/socket.h | 1 + arch/avr32/include/asm/socket.h | 1 + arch/cris/include/asm/socket.h | 1 + arch/frv/include/asm/socket.h | 1 + arch/h8300/include/asm/socket.h | 1 + arch/ia64/include/asm/socket.h | 1 + arch/m32r/include/asm/socket.h | 1 + arch/m68k/include/asm/socket.h | 1 + arch/mips/include/asm/socket.h | 1 + arch/mn10300/include/asm/socket.h | 1 + arch/parisc/include/asm/socket.h | 1 + arch/powerpc/include/asm/socket.h | 1 + arch/s390/include/asm/socket.h | 1 + arch/sparc/include/asm/socket.h | 1 + arch/xtensa/include/asm/socket.h | 1 + include/asm-generic/socket.h | 1 + include/linux/net.h | 1 + include/net/sock.h | 25 +++++++++++++++++++++++++ net/core/sock.c | 13 +++++++++++++ 20 files changed, 56 insertions(+) diff --git a/arch/alpha/include/asm/socket.h b/arch/alpha/include/asm/socket.h index 082355f159e67..16449d330dae9 100644 --- a/arch/alpha/include/asm/socket.h +++ b/arch/alpha/include/asm/socket.h @@ -71,6 +71,7 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 /* O_NONBLOCK clashes with the bits used for socket types. Therefore we * have to define SOCK_NONBLOCK to a different value here. diff --git a/arch/arm/include/asm/socket.h b/arch/arm/include/asm/socket.h index dec6f9afb3cf9..d958c74e52608 100644 --- a/arch/arm/include/asm/socket.h +++ b/arch/arm/include/asm/socket.h @@ -64,5 +64,6 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #endif /* _ASM_SOCKET_H */ diff --git a/arch/avr32/include/asm/socket.h b/arch/avr32/include/asm/socket.h index 247b88c760bef..30078f98b3ab8 100644 --- a/arch/avr32/include/asm/socket.h +++ b/arch/avr32/include/asm/socket.h @@ -64,5 +64,6 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #endif /* __ASM_AVR32_SOCKET_H */ diff --git a/arch/cris/include/asm/socket.h b/arch/cris/include/asm/socket.h index e269264df7c4f..048aba64600c9 100644 --- a/arch/cris/include/asm/socket.h +++ b/arch/cris/include/asm/socket.h @@ -66,6 +66,7 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #endif /* _ASM_SOCKET_H */ diff --git a/arch/frv/include/asm/socket.h b/arch/frv/include/asm/socket.h index ce80fdadcce57..7a361810f3cce 100644 --- a/arch/frv/include/asm/socket.h +++ b/arch/frv/include/asm/socket.h @@ -64,6 +64,7 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #endif /* _ASM_SOCKET_H */ diff --git a/arch/h8300/include/asm/socket.h b/arch/h8300/include/asm/socket.h index cf1daab6f27ef..e7bbfcee5b991 100644 --- a/arch/h8300/include/asm/socket.h +++ b/arch/h8300/include/asm/socket.h @@ -64,5 +64,6 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #endif /* _ASM_SOCKET_H */ diff --git a/arch/ia64/include/asm/socket.h b/arch/ia64/include/asm/socket.h index 4b03664e3fb50..ced62de9d5a92 100644 --- a/arch/ia64/include/asm/socket.h +++ b/arch/ia64/include/asm/socket.h @@ -73,5 +73,6 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #endif /* _ASM_IA64_SOCKET_H */ diff --git a/arch/m32r/include/asm/socket.h b/arch/m32r/include/asm/socket.h index e8b8c5bb053c1..696cb4c7ca4e4 100644 --- a/arch/m32r/include/asm/socket.h +++ b/arch/m32r/include/asm/socket.h @@ -64,5 +64,6 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #endif /* _ASM_M32R_SOCKET_H */ diff --git a/arch/m68k/include/asm/socket.h b/arch/m68k/include/asm/socket.h index d4708ce466e06..e8b41a6775f9c 100644 --- a/arch/m68k/include/asm/socket.h +++ b/arch/m68k/include/asm/socket.h @@ -64,5 +64,6 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #endif /* _ASM_SOCKET_H */ diff --git a/arch/mips/include/asm/socket.h b/arch/mips/include/asm/socket.h index ad5c0a7a02a7e..52104872e9e36 100644 --- a/arch/mips/include/asm/socket.h +++ b/arch/mips/include/asm/socket.h @@ -84,6 +84,7 @@ To add: #define SO_REUSEPORT 0x0200 /* Allow local address and port reuse. */ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #ifdef __KERNEL__ diff --git a/arch/mn10300/include/asm/socket.h b/arch/mn10300/include/asm/socket.h index 876356d785224..013fcc51698f8 100644 --- a/arch/mn10300/include/asm/socket.h +++ b/arch/mn10300/include/asm/socket.h @@ -64,5 +64,6 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #endif /* _ASM_SOCKET_H */ diff --git a/arch/parisc/include/asm/socket.h b/arch/parisc/include/asm/socket.h index d28c51b61067e..f717c9bec16fe 100644 --- a/arch/parisc/include/asm/socket.h +++ b/arch/parisc/include/asm/socket.h @@ -63,6 +63,7 @@ #define SO_WIFI_STATUS 0x4022 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 0x4023 /* O_NONBLOCK clashes with the bits used for socket types. Therefore we * have to define SOCK_NONBLOCK to a different value here. diff --git a/arch/powerpc/include/asm/socket.h b/arch/powerpc/include/asm/socket.h index 2fc2af8fbf59b..fe1c0b478fd7b 100644 --- a/arch/powerpc/include/asm/socket.h +++ b/arch/powerpc/include/asm/socket.h @@ -71,5 +71,6 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #endif /* _ASM_POWERPC_SOCKET_H */ diff --git a/arch/s390/include/asm/socket.h b/arch/s390/include/asm/socket.h index 67b5c1b14b511..581702fa1b0c5 100644 --- a/arch/s390/include/asm/socket.h +++ b/arch/s390/include/asm/socket.h @@ -72,5 +72,6 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #endif /* _ASM_SOCKET_H */ diff --git a/arch/sparc/include/asm/socket.h b/arch/sparc/include/asm/socket.h index 8af1b64168b3a..68e2e2746f6f8 100644 --- a/arch/sparc/include/asm/socket.h +++ b/arch/sparc/include/asm/socket.h @@ -60,6 +60,7 @@ #define SO_WIFI_STATUS 0x0025 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 0x0026 /* Security levels - as per NRL IPv6 - don't actually do anything */ #define SO_SECURITY_AUTHENTICATION 0x5001 diff --git a/arch/xtensa/include/asm/socket.h b/arch/xtensa/include/asm/socket.h index bb06968be227b..74818b161362b 100644 --- a/arch/xtensa/include/asm/socket.h +++ b/arch/xtensa/include/asm/socket.h @@ -75,5 +75,6 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #endif /* _XTENSA_SOCKET_H */ diff --git a/include/asm-generic/socket.h b/include/asm-generic/socket.h index 49c1704173e75..d9aaac0c36d46 100644 --- a/include/asm-generic/socket.h +++ b/include/asm-generic/socket.h @@ -67,4 +67,5 @@ #define SO_WIFI_STATUS 41 #define SCM_WIFI_STATUS SO_WIFI_STATUS +#define SO_PEEK_OFF 42 #endif /* __ASM_GENERIC_SOCKET_H */ diff --git a/include/linux/net.h b/include/linux/net.h index b29923006b11e..be60c7f5e145d 100644 --- a/include/linux/net.h +++ b/include/linux/net.h @@ -206,6 +206,7 @@ struct proto_ops { int offset, size_t size, int flags); ssize_t (*splice_read)(struct socket *sock, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags); + void (*set_peek_off)(struct sock *sk, int val); }; #define DECLARE_SOCKADDR(type, dst, src) \ diff --git a/include/net/sock.h b/include/net/sock.h index 91c1c8baf020d..9c0553b9e451a 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -357,6 +357,7 @@ struct sock { struct page *sk_sndmsg_page; struct sk_buff *sk_send_head; __u32 sk_sndmsg_off; + __s32 sk_peek_off; int sk_write_pending; #ifdef CONFIG_SECURITY void *sk_security; @@ -373,6 +374,30 @@ struct sock { void (*sk_destruct)(struct sock *sk); }; +static inline int sk_peek_offset(struct sock *sk, int flags) +{ + if ((flags & MSG_PEEK) && (sk->sk_peek_off >= 0)) + return sk->sk_peek_off; + else + return 0; +} + +static inline void sk_peek_offset_bwd(struct sock *sk, int val) +{ + if (sk->sk_peek_off >= 0) { + if (sk->sk_peek_off >= val) + sk->sk_peek_off -= val; + else + sk->sk_peek_off = 0; + } +} + +static inline void sk_peek_offset_fwd(struct sock *sk, int val) +{ + if (sk->sk_peek_off >= 0) + sk->sk_peek_off += val; +} + /* * Hashed lists helper routines */ diff --git a/net/core/sock.c b/net/core/sock.c index 02f8dfe320b77..19942d4bb6e6e 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -793,6 +793,12 @@ set_rcvbuf: sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); break; + case SO_PEEK_OFF: + if (sock->ops->set_peek_off) + sock->ops->set_peek_off(sk, val); + else + ret = -EOPNOTSUPP; + break; default: ret = -ENOPROTOOPT; break; @@ -1018,6 +1024,12 @@ int sock_getsockopt(struct socket *sock, int level, int optname, v.val = !!sock_flag(sk, SOCK_WIFI_STATUS); break; + case SO_PEEK_OFF: + if (!sock->ops->set_peek_off) + return -EOPNOTSUPP; + + v.val = sk->sk_peek_off; + break; default: return -ENOPROTOOPT; } @@ -2092,6 +2104,7 @@ void sock_init_data(struct socket *sock, struct sock *sk) sk->sk_sndmsg_page = NULL; sk->sk_sndmsg_off = 0; + sk->sk_peek_off = -1; sk->sk_peer_pid = NULL; sk->sk_peer_cred = NULL; -- 2.39.5