20 files changed, 56 insertions, 0 deletions

diff --git a/arch/alpha/include/asm/socket.h b/arch/alpha/include/asm/socket.h
index 082355f159e6..16449d330dae 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 dec6f9afb3cf..d958c74e5260 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 247b88c760be..30078f98b3ab 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 e269264df7c4..048aba64600c 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 ce80fdadcce5..7a361810f3cc 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 cf1daab6f27e..e7bbfcee5b99 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 4b03664e3fb5..ced62de9d5a9 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 e8b8c5bb053c..696cb4c7ca4e 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 d4708ce466e0..e8b41a6775f9 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 ad5c0a7a02a7..52104872e9e3 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 876356d78522..013fcc51698f 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 d28c51b61067..f717c9bec16f 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 2fc2af8fbf59..fe1c0b478fd7 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 67b5c1b14b51..581702fa1b0c 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 8af1b64168b3..68e2e2746f6f 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 bb06968be227..74818b161362 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 49c1704173e7..d9aaac0c36d4 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 b29923006b11..be60c7f5e145 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 91c1c8baf020..9c0553b9e451 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 02f8dfe320b7..19942d4bb6e6 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;