diff --git a/arch/alpha/include/asm/socket.h b/arch/alpha/include/asm/socket.h
index 2f8b4d3..26773e3 100644
--- a/arch/alpha/include/asm/socket.h
+++ b/arch/alpha/include/asm/socket.h
@@ -33,6 +33,7 @@
 #define	SO_SNDTIMEO	0x1013
 #define SO_ACCEPTCONN	0x1014
 #define SO_PROTOCOL	0x1028
+#define SO_DOMAIN	0x1029
 
 /* linux-specific, might as well be the same as on i386 */
 #define SO_NO_CHECK	11
diff --git a/arch/arm/include/asm/socket.h b/arch/arm/include/asm/socket.h
index 7f47454..92ac61d 100644
--- a/arch/arm/include/asm/socket.h
+++ b/arch/arm/include/asm/socket.h
@@ -58,5 +58,6 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif /* _ASM_SOCKET_H */
diff --git a/arch/avr32/include/asm/socket.h b/arch/avr32/include/asm/socket.h
index 6af2866..fe863f9 100644
--- a/arch/avr32/include/asm/socket.h
+++ b/arch/avr32/include/asm/socket.h
@@ -58,5 +58,6 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif /* __ASM_AVR32_SOCKET_H */
diff --git a/arch/cris/include/asm/socket.h b/arch/cris/include/asm/socket.h
index f3859fb..45ec49b 100644
--- a/arch/cris/include/asm/socket.h
+++ b/arch/cris/include/asm/socket.h
@@ -60,6 +60,7 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif /* _ASM_SOCKET_H */
 
diff --git a/arch/frv/include/asm/socket.h b/arch/frv/include/asm/socket.h
index 8dab348..2dea726 100644
--- a/arch/frv/include/asm/socket.h
+++ b/arch/frv/include/asm/socket.h
@@ -58,6 +58,7 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif /* _ASM_SOCKET_H */
 
diff --git a/arch/h8300/include/asm/socket.h b/arch/h8300/include/asm/socket.h
index ba770d0..1547f01 100644
--- a/arch/h8300/include/asm/socket.h
+++ b/arch/h8300/include/asm/socket.h
@@ -58,5 +58,6 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif /* _ASM_SOCKET_H */
diff --git a/arch/ia64/include/asm/socket.h b/arch/ia64/include/asm/socket.h
index 091cd9d..0b0d5ff 100644
--- a/arch/ia64/include/asm/socket.h
+++ b/arch/ia64/include/asm/socket.h
@@ -67,5 +67,6 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif /* _ASM_IA64_SOCKET_H */
diff --git a/arch/m32r/include/asm/socket.h b/arch/m32r/include/asm/socket.h
index d36f592..3390a86 100644
--- a/arch/m32r/include/asm/socket.h
+++ b/arch/m32r/include/asm/socket.h
@@ -58,5 +58,6 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif /* _ASM_M32R_SOCKET_H */
diff --git a/arch/m68k/include/asm/socket.h b/arch/m68k/include/asm/socket.h
index 060cb7e..eee01cc 100644
--- a/arch/m68k/include/asm/socket.h
+++ b/arch/m68k/include/asm/socket.h
@@ -58,5 +58,6 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif /* _ASM_SOCKET_H */
diff --git a/arch/microblaze/include/asm/socket.h b/arch/microblaze/include/asm/socket.h
index 96bf8bf..7361ae7 100644
--- a/arch/microblaze/include/asm/socket.h
+++ b/arch/microblaze/include/asm/socket.h
@@ -67,5 +67,6 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif /* _ASM_MICROBLAZE_SOCKET_H */
diff --git a/arch/mips/include/asm/socket.h b/arch/mips/include/asm/socket.h
index 289ce5f..ae05acc 100644
--- a/arch/mips/include/asm/socket.h
+++ b/arch/mips/include/asm/socket.h
@@ -43,6 +43,7 @@ To add: #define SO_REUSEPORT 0x0200	/* Allow local address and port reuse.  */
 #define SO_RCVTIMEO 	0x1006	/* receive timeout */
 #define SO_ACCEPTCONN	0x1009
 #define SO_PROTOCOL	0x1028	/* protocol type */
+#define SO_DOMAIN	0x1029	/* domain/socket family */
 
 /* linux-specific, might as well be the same as on i386 */
 #define SO_NO_CHECK	11
diff --git a/arch/mn10300/include/asm/socket.h b/arch/mn10300/include/asm/socket.h
index 19d7cf7..4df75af 100644
--- a/arch/mn10300/include/asm/socket.h
+++ b/arch/mn10300/include/asm/socket.h
@@ -58,5 +58,6 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif /* _ASM_SOCKET_H */
diff --git a/arch/parisc/include/asm/socket.h b/arch/parisc/include/asm/socket.h
index a658b09..960b1e5 100644
--- a/arch/parisc/include/asm/socket.h
+++ b/arch/parisc/include/asm/socket.h
@@ -25,6 +25,7 @@
 #define SO_ERROR	0x1007
 #define SO_TYPE		0x1008
 #define SO_PROTOCOL	0x1028
+#define SO_DOMAIN	0x1029
 #define SO_PEERNAME	0x2000
 
 #define SO_NO_CHECK	0x400b
diff --git a/arch/powerpc/include/asm/socket.h b/arch/powerpc/include/asm/socket.h
index 609049d..3ab8b3e 100644
--- a/arch/powerpc/include/asm/socket.h
+++ b/arch/powerpc/include/asm/socket.h
@@ -65,5 +65,6 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif	/* _ASM_POWERPC_SOCKET_H */
diff --git a/arch/s390/include/asm/socket.h b/arch/s390/include/asm/socket.h
index 65baa9a..e42df89 100644
--- a/arch/s390/include/asm/socket.h
+++ b/arch/s390/include/asm/socket.h
@@ -66,5 +66,6 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif /* _ASM_SOCKET_H */
diff --git a/arch/sparc/include/asm/socket.h b/arch/sparc/include/asm/socket.h
index 9cbbfaf..3a5ae3d 100644
--- a/arch/sparc/include/asm/socket.h
+++ b/arch/sparc/include/asm/socket.h
@@ -30,6 +30,7 @@
 #define SO_ERROR	0x1007
 #define SO_TYPE		0x1008
 #define SO_PROTOCOL	0x1028
+#define SO_DOMAIN	0x1029
 
 
 /* Linux specific, keep the same. */
diff --git a/arch/x86/include/asm/socket.h b/arch/x86/include/asm/socket.h
index 1077d25..b2a8c74 100644
--- a/arch/x86/include/asm/socket.h
+++ b/arch/x86/include/asm/socket.h
@@ -58,5 +58,6 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif /* _ASM_X86_SOCKET_H */
diff --git a/arch/xtensa/include/asm/socket.h b/arch/xtensa/include/asm/socket.h
index e47f172..beb3a6b 100644
--- a/arch/xtensa/include/asm/socket.h
+++ b/arch/xtensa/include/asm/socket.h
@@ -69,5 +69,6 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif	/* _XTENSA_SOCKET_H */
diff --git a/include/asm-generic/socket.h b/include/asm-generic/socket.h
index 7e24d18..538991c 100644
--- a/include/asm-generic/socket.h
+++ b/include/asm-generic/socket.h
@@ -61,5 +61,6 @@
 #define SCM_TIMESTAMPING	SO_TIMESTAMPING
 
 #define SO_PROTOCOL		38
+#define SO_DOMAIN		39
 
 #endif /* __ASM_GENERIC_SOCKET_H */
diff --git a/net/core/sock.c b/net/core/sock.c
index fb71d9e..025317f 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -483,6 +483,7 @@ int sock_setsockopt(struct socket *sock, int level, int optname,
 		break;
 	case SO_TYPE:
 	case SO_PROTOCOL:
+	case SO_DOMAIN:
 	case SO_ERROR:
 		ret = -ENOPROTOOPT;
 		break;
@@ -769,6 +770,10 @@ int sock_getsockopt(struct socket *sock, int level, int optname,
 		v.val = sk->sk_protocol;
 		break;
 
+	case SO_DOMAIN:
+		v.val = sk->sk_family;
+		break;
+
 	case SO_ERROR:
 		v.val = -sock_error(sk);
 		if (v.val == 0)
