net: Introduce recvmmsg socket syscall

Meaning receive multiple messages, reducing the number of syscalls and
net stack entry/exit operations.

Next patches will introduce mechanisms where protocols that want to
optimize this operation will provide an unlocked_recvmsg operation.

This takes into account comments made by:

. Paul Moore: sock_recvmsg is called only for the first datagram,
  sock_recvmsg_nosec is used for the rest.

. Caitlin Bestler: recvmmsg now has a struct timespec timeout, that
  works in the same fashion as the ppoll one.

  If the underlying protocol returns a datagram with MSG_OOB set, this
  will make recvmmsg return right away with as many datagrams (+ the OOB
  one) it has received so far.

. Rémi Denis-Courmont & Steven Whitehouse: If we receive N < vlen
  datagrams and then recvmsg returns an error, recvmmsg will return
  the successfully received datagrams, store the error and return it
  in the next call.

This paves the way for a subsequent optimization, sk_prot->unlocked_recvmsg,
where we will be able to acquire the lock only at batch start and end, not at
every underlying recvmsg call.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

25 files changed, 261 insertions, 50 deletions

diff --git a/arch/alpha/kernel/systbls.S b/arch/alpha/kernel/systbls.S
index 95c9aef1c106..cda6b8b3d573 100644
--- a/arch/alpha/kernel/systbls.S
+++ b/arch/alpha/kernel/systbls.S
@@ -497,6 +497,7 @@ sys_call_table:
         .quad sys_signalfd
         .quad sys_ni_syscall
         .quad sys_eventfd
+        .quad sys_recvmmsg
 
         .size sys_call_table, . - sys_call_table
         .type sys_call_table, @object
diff --git a/arch/arm/kernel/calls.S b/arch/arm/kernel/calls.S
index fafce1b5c69f..f58c1156e779 100644
--- a/arch/arm/kernel/calls.S
+++ b/arch/arm/kernel/calls.S
@@ -374,6 +374,7 @@
                 CALL(sys_pwritev)
                 CALL(sys_rt_tgsigqueueinfo)
                 CALL(sys_perf_event_open)
+/* 365 */       CALL(sys_recvmmsg)
 #ifndef syscalls_counted
 .equ syscalls_padding, ((NR_syscalls + 3) & ~3) - NR_syscalls
 #define syscalls_counted
diff --git a/arch/avr32/kernel/syscall_table.S b/arch/avr32/kernel/syscall_table.S
index 7ee0057613b3..e76bad16b0f0 100644
--- a/arch/avr32/kernel/syscall_table.S
+++ b/arch/avr32/kernel/syscall_table.S
@@ -295,4 +295,5 @@ sys_call_table:
         .long   sys_signalfd
         .long   sys_ni_syscall          /* 280, was sys_timerfd */
         .long   sys_eventfd
+        .long   sys_recvmmsg
         .long   sys_ni_syscall          /* r8 is saturated at nr_syscalls */
diff --git a/arch/blackfin/mach-common/entry.S b/arch/blackfin/mach-common/entry.S
index 1e7cac23e25f..48692724b74c 100644
--- a/arch/blackfin/mach-common/entry.S
+++ b/arch/blackfin/mach-common/entry.S
@@ -1621,6 +1621,7 @@ ENTRY(_sys_call_table)
         .long _sys_pwritev
         .long _sys_rt_tgsigqueueinfo
         .long _sys_perf_event_open
+        .long _sys_recvmmsg             /* 370 */
 
         .rept NR_syscalls-(.-_sys_call_table)/4
         .long _sys_ni_syscall
diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S
index d0e7d37017b4..d75b872ca4dc 100644
--- a/arch/ia64/kernel/entry.S
+++ b/arch/ia64/kernel/entry.S
@@ -1806,6 +1806,7 @@ sys_call_table:
         data8 sys_preadv
         data8 sys_pwritev                       // 1320
         data8 sys_rt_tgsigqueueinfo
+        data8 sys_recvmmsg
 
         .org sys_call_table + 8*NR_syscalls     // guard against failures to increase NR_syscalls
 #endif /* __IA64_ASM_PARAVIRTUALIZED_NATIVE */
diff --git a/arch/microblaze/kernel/syscall_table.S b/arch/microblaze/kernel/syscall_table.S
index ecec19155135..c1ab1dc10898 100644
--- a/arch/microblaze/kernel/syscall_table.S
+++ b/arch/microblaze/kernel/syscall_table.S
@@ -371,3 +371,4 @@ ENTRY(sys_call_table)
         .long sys_ni_syscall
         .long sys_rt_tgsigqueueinfo     /* 365 */
         .long sys_perf_event_open
+        .long sys_recvmmsg
diff --git a/arch/mips/kernel/scall32-o32.S b/arch/mips/kernel/scall32-o32.S
index fd2a9bb620d6..17202bbe843f 100644
--- a/arch/mips/kernel/scall32-o32.S
+++ b/arch/mips/kernel/scall32-o32.S
@@ -583,6 +583,7 @@ einval:	li	v0, -ENOSYS
         sys     sys_rt_tgsigqueueinfo   4
         sys     sys_perf_event_open     5
         sys     sys_accept4             4
+        sys     sys_recvmmsg            5
         .endm
 
         /* We pre-compute the number of _instruction_ bytes needed to
diff --git a/arch/mips/kernel/scall64-64.S b/arch/mips/kernel/scall64-64.S
index 18bf7f32c5e4..a8a6c596eb04 100644
--- a/arch/mips/kernel/scall64-64.S
+++ b/arch/mips/kernel/scall64-64.S
@@ -420,4 +420,5 @@ sys_call_table:
         PTR     sys_rt_tgsigqueueinfo
         PTR     sys_perf_event_open
         PTR     sys_accept4
+        PTR     sys_recvmmsg
         .size   sys_call_table,.-sys_call_table
diff --git a/arch/mips/kernel/scall64-n32.S b/arch/mips/kernel/scall64-n32.S
index 6ebc07976694..5154e64f7cfe 100644
--- a/arch/mips/kernel/scall64-n32.S
+++ b/arch/mips/kernel/scall64-n32.S
@@ -418,4 +418,5 @@ EXPORT(sysn32_call_table)
         PTR     compat_sys_rt_tgsigqueueinfo    /* 5295 */
         PTR     sys_perf_event_open
         PTR     sys_accept4
+        PTR     compat_sys_recvmmsg
         .size   sysn32_call_table,.-sysn32_call_table
diff --git a/arch/mips/kernel/scall64-o32.S b/arch/mips/kernel/scall64-o32.S
index 9bbf9775e0bd..d0eff53d7cb9 100644
--- a/arch/mips/kernel/scall64-o32.S
+++ b/arch/mips/kernel/scall64-o32.S
@@ -538,4 +538,5 @@ sys_call_table:
         PTR     compat_sys_rt_tgsigqueueinfo
         PTR     sys_perf_event_open
         PTR     sys_accept4
+        PTR     compat_sys_recvmmsg
         .size   sys_call_table,.-sys_call_table
diff --git a/arch/sh/kernel/syscalls_64.S b/arch/sh/kernel/syscalls_64.S
index 5bfde6c77498..07d2aaea9ae8 100644
--- a/arch/sh/kernel/syscalls_64.S
+++ b/arch/sh/kernel/syscalls_64.S
@@ -391,3 +391,4 @@ sys_call_table:
         .long sys_pwritev
         .long sys_rt_tgsigqueueinfo
         .long sys_perf_event_open
+        .long sys_recvmmsg              /* 365 */
diff --git a/arch/sparc/kernel/systbls_32.S b/arch/sparc/kernel/systbls_32.S
index 0f1658d37490..ceb1530f8aa6 100644
--- a/arch/sparc/kernel/systbls_32.S
+++ b/arch/sparc/kernel/systbls_32.S
@@ -82,5 +82,5 @@ sys_call_table:
 /*310*/ .long sys_utimensat, sys_signalfd, sys_timerfd_create, sys_eventfd, sys_fallocate
 /*315*/ .long sys_timerfd_settime, sys_timerfd_gettime, sys_signalfd4, sys_eventfd2, sys_epoll_create1
 /*320*/ .long sys_dup3, sys_pipe2, sys_inotify_init1, sys_accept4, sys_preadv
-/*325*/ .long sys_pwritev, sys_rt_tgsigqueueinfo, sys_perf_event_open
+/*325*/ .long sys_pwritev, sys_rt_tgsigqueueinfo, sys_perf_event_open, sys_recvmmsg
 
diff --git a/arch/sparc/kernel/systbls_64.S b/arch/sparc/kernel/systbls_64.S
index 009825f6e73c..f37bef747e60 100644
--- a/arch/sparc/kernel/systbls_64.S
+++ b/arch/sparc/kernel/systbls_64.S
@@ -83,7 +83,7 @@ sys_call_table32:
 /*310*/ .word compat_sys_utimensat, compat_sys_signalfd, sys_timerfd_create, sys_eventfd, compat_sys_fallocate
         .word compat_sys_timerfd_settime, compat_sys_timerfd_gettime, compat_sys_signalfd4, sys_eventfd2, sys_epoll_create1
 /*320*/ .word sys_dup3, sys_pipe2, sys_inotify_init1, sys_accept4, compat_sys_preadv
-        .word compat_sys_pwritev, compat_sys_rt_tgsigqueueinfo, sys_perf_event_open
+        .word compat_sys_pwritev, compat_sys_rt_tgsigqueueinfo, sys_perf_event_open, compat_sys_recvmmsg
 
 #endif /* CONFIG_COMPAT */
 
@@ -158,4 +158,4 @@ sys_call_table:
 /*310*/ .word sys_utimensat, sys_signalfd, sys_timerfd_create, sys_eventfd, sys_fallocate
         .word sys_timerfd_settime, sys_timerfd_gettime, sys_signalfd4, sys_eventfd2, sys_epoll_create1
 /*320*/ .word sys_dup3, sys_pipe2, sys_inotify_init1, sys_accept4, sys_preadv
-        .word sys_pwritev, sys_rt_tgsigqueueinfo, sys_perf_event_open
+        .word sys_pwritev, sys_rt_tgsigqueueinfo, sys_perf_event_open, sys_recvmmsg
diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S
index 74619c4f9fda..11a6c79d5f46 100644
--- a/arch/x86/ia32/ia32entry.S
+++ b/arch/x86/ia32/ia32entry.S
@@ -832,4 +832,5 @@ ia32_sys_call_table:
         .quad compat_sys_pwritev
         .quad compat_sys_rt_tgsigqueueinfo      /* 335 */
         .quad sys_perf_event_open
+        .quad compat_sys_recvmmsg
 ia32_syscall_end:
diff --git a/arch/x86/include/asm/unistd_32.h b/arch/x86/include/asm/unistd_32.h
index 6fb3c209a7e3..3baf379fa840 100644
--- a/arch/x86/include/asm/unistd_32.h
+++ b/arch/x86/include/asm/unistd_32.h
@@ -342,10 +342,11 @@
 #define __NR_pwritev            334
 #define __NR_rt_tgsigqueueinfo  335
 #define __NR_perf_event_open    336
+#define __NR_recvmmsg           337
 
 #ifdef __KERNEL__
 
-#define NR_syscalls 337
+#define NR_syscalls 338
 
 #define __ARCH_WANT_IPC_PARSE_VERSION
 #define __ARCH_WANT_OLD_READDIR
diff --git a/arch/x86/include/asm/unistd_64.h b/arch/x86/include/asm/unistd_64.h
index 8d3ad0adbc68..4843f7ba754a 100644
--- a/arch/x86/include/asm/unistd_64.h
+++ b/arch/x86/include/asm/unistd_64.h
@@ -661,6 +661,8 @@ __SYSCALL(__NR_pwritev, sys_pwritev)
 __SYSCALL(__NR_rt_tgsigqueueinfo, sys_rt_tgsigqueueinfo)
 #define __NR_perf_event_open                    298
 __SYSCALL(__NR_perf_event_open, sys_perf_event_open)
+#define __NR_recvmmsg                           299
+__SYSCALL(__NR_recvmmsg, sys_recvmmsg)
 
 #ifndef __NO_STUBS
 #define __ARCH_WANT_OLD_READDIR
diff --git a/arch/x86/kernel/syscall_table_32.S b/arch/x86/kernel/syscall_table_32.S
index 0157cd26d7cc..70c2125d55b9 100644
--- a/arch/x86/kernel/syscall_table_32.S
+++ b/arch/x86/kernel/syscall_table_32.S
@@ -336,3 +336,4 @@ ENTRY(sys_call_table)
         .long sys_pwritev
         .long sys_rt_tgsigqueueinfo     /* 335 */
         .long sys_perf_event_open
+        .long sys_recvmmsg
diff --git a/arch/xtensa/include/asm/unistd.h b/arch/xtensa/include/asm/unistd.h
index c092c8fbb2cf..4e55dc763021 100644
--- a/arch/xtensa/include/asm/unistd.h
+++ b/arch/xtensa/include/asm/unistd.h
@@ -681,8 +681,10 @@ __SYSCALL(304, sys_signalfd, 3)
 __SYSCALL(305, sys_ni_syscall, 0)
 #define __NR_eventfd                            306
 __SYSCALL(306, sys_eventfd, 1)
+#define __NR_recvmmsg                           307
+__SYSCALL(307, sys_recvmmsg, 5)
 
-#define __NR_syscall_count                      307
+#define __NR_syscall_count                      308
 
 /*
  * sysxtensa syscall handler
diff --git a/include/linux/net.h b/include/linux/net.h
index 529a0931711d..b42bb60fe92f 100644
--- a/include/linux/net.h
+++ b/include/linux/net.h
@@ -41,6 +41,7 @@
 #define SYS_SENDMSG     16              /* sys_sendmsg(2)               */
 #define SYS_RECVMSG     17              /* sys_recvmsg(2)               */
 #define SYS_ACCEPT4     18              /* sys_accept4(2)               */
+#define SYS_RECVMMSG    19              /* sys_recvmmsg(2)              */
 
 typedef enum {
         SS_FREE = 0,                    /* not allocated                */
diff --git a/include/linux/socket.h b/include/linux/socket.h
index 3273a0c5043b..59966f12990c 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -65,6 +65,12 @@ struct msghdr {
         unsigned        msg_flags;
 };
 
+/* For recvmmsg/sendmmsg */
+struct mmsghdr {
+        struct msghdr   msg_hdr;
+        unsigned        msg_len;
+};
+
 /*
  *      POSIX 1003.1g - ancillary data object information
  *      Ancillary data consits of a sequence of pairs of
@@ -312,6 +318,10 @@ extern int move_addr_to_user(struct sockaddr *kaddr, int klen, void __user *uadd
 extern int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr *kaddr);
 extern int put_cmsg(struct msghdr*, int level, int type, int len, void *data);
 
+struct timespec;
+
+extern int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
+                          unsigned int flags, struct timespec *timeout);
 #endif
 #endif /* not kernel and not glibc */
 #endif /* _LINUX_SOCKET_H */
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index a990ace1a838..714f063a3e6d 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -25,6 +25,7 @@ struct linux_dirent64;
 struct list_head;
 struct msgbuf;
 struct msghdr;
+struct mmsghdr;
 struct msqid_ds;
 struct new_utsname;
 struct nfsctl_arg;
@@ -677,6 +678,9 @@ asmlinkage long sys_recv(int, void __user *, size_t, unsigned);
 asmlinkage long sys_recvfrom(int, void __user *, size_t, unsigned,
                                 struct sockaddr __user *, int __user *);
 asmlinkage long sys_recvmsg(int fd, struct msghdr __user *msg, unsigned flags);
+asmlinkage long sys_recvmmsg(int fd, struct mmsghdr __user *msg,
+                             unsigned int vlen, unsigned flags,
+                             struct timespec __user *timeout);
 asmlinkage long sys_socket(int, int, int);
 asmlinkage long sys_socketpair(int, int, int, int __user *);
 asmlinkage long sys_socketcall(int call, unsigned long __user *args);
diff --git a/include/net/compat.h b/include/net/compat.h
index 7c3002832d05..9679f05e9896 100644
--- a/include/net/compat.h
+++ b/include/net/compat.h
@@ -18,6 +18,11 @@ struct compat_msghdr {
         compat_uint_t   msg_flags;
 };
 
+struct compat_mmsghdr {
+        struct compat_msghdr msg_hdr;
+        compat_uint_t        msg_len;
+};
+
 struct compat_cmsghdr {
         compat_size_t   cmsg_len;
         compat_int_t    cmsg_level;
@@ -35,6 +40,9 @@ extern int get_compat_msghdr(struct msghdr *, struct compat_msghdr __user *);
 extern int verify_compat_iovec(struct msghdr *, struct iovec *, struct sockaddr *, int);
 extern asmlinkage long compat_sys_sendmsg(int,struct compat_msghdr __user *,unsigned);
 extern asmlinkage long compat_sys_recvmsg(int,struct compat_msghdr __user *,unsigned);
+extern asmlinkage long compat_sys_recvmmsg(int, struct compat_mmsghdr __user *,
+                                           unsigned, unsigned,
+                                           struct timespec __user *);
 extern asmlinkage long compat_sys_getsockopt(int, int, int, char __user *, int __user *);
 extern int put_cmsg_compat(struct msghdr*, int, int, int, void *);
 
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index e06d0b8d1951..f050ba85d420 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -48,8 +48,10 @@ cond_syscall(sys_shutdown);
 cond_syscall(sys_sendmsg);
 cond_syscall(compat_sys_sendmsg);
 cond_syscall(sys_recvmsg);
+cond_syscall(sys_recvmmsg);
 cond_syscall(compat_sys_recvmsg);
 cond_syscall(compat_sys_recvfrom);
+cond_syscall(compat_sys_recvmmsg);
 cond_syscall(sys_socketcall);
 cond_syscall(sys_futex);
 cond_syscall(compat_sys_futex);
diff --git a/net/compat.c b/net/compat.c
index a407c3addbae..e13f5256fd20 100644
--- a/net/compat.c
+++ b/net/compat.c
@@ -727,10 +727,10 @@ EXPORT_SYMBOL(compat_mc_getsockopt);
 
 /* Argument list sizes for compat_sys_socketcall */
 #define AL(x) ((x) * sizeof(u32))
-static unsigned char nas[19]={AL(0),AL(3),AL(3),AL(3),AL(2),AL(3),
+static unsigned char nas[20]={AL(0),AL(3),AL(3),AL(3),AL(2),AL(3),
                                 AL(3),AL(3),AL(4),AL(4),AL(4),AL(6),
                                 AL(6),AL(2),AL(5),AL(5),AL(3),AL(3),
-                                AL(4)};
+                                AL(4),AL(5)};
 #undef AL
 
 asmlinkage long compat_sys_sendmsg(int fd, struct compat_msghdr __user *msg, unsigned flags)
@@ -755,13 +755,36 @@ asmlinkage long compat_sys_recvfrom(int fd, void __user *buf, size_t len,
         return sys_recvfrom(fd, buf, len, flags | MSG_CMSG_COMPAT, addr, addrlen);
 }
 
+asmlinkage long compat_sys_recvmmsg(int fd, struct compat_mmsghdr __user *mmsg,
+                                    unsigned vlen, unsigned int flags,
+                                    struct timespec __user *timeout)
+{
+        int datagrams;
+        struct timespec ktspec;
+        struct compat_timespec __user *utspec =
+                        (struct compat_timespec __user *)timeout;
+
+        if (get_user(ktspec.tv_sec, &utspec->tv_sec) ||
+            get_user(ktspec.tv_nsec, &utspec->tv_nsec))
+                return -EFAULT;
+
+        datagrams = __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
+                                   flags | MSG_CMSG_COMPAT, &ktspec);
+        if (datagrams > 0 &&
+            (put_user(ktspec.tv_sec, &utspec->tv_sec) ||
+             put_user(ktspec.tv_nsec, &utspec->tv_nsec)))
+                datagrams = -EFAULT;
+
+        return datagrams;
+}
+
 asmlinkage long compat_sys_socketcall(int call, u32 __user *args)
 {
         int ret;
         u32 a[6];
         u32 a0, a1;
 
-        if (call < SYS_SOCKET || call > SYS_ACCEPT4)
+        if (call < SYS_SOCKET || call > SYS_RECVMMSG)
                 return -EINVAL;
         if (copy_from_user(a, args, nas[call]))
                 return -EFAULT;
@@ -823,6 +846,10 @@ asmlinkage long compat_sys_socketcall(int call, u32 __user *args)
         case SYS_RECVMSG:
                 ret = compat_sys_recvmsg(a0, compat_ptr(a1), a[2]);
                 break;
+        case SYS_RECVMMSG:
+                ret = compat_sys_recvmmsg(a0, compat_ptr(a1), a[2], a[3],
+                                          compat_ptr(a[4]));
+                break;
         case SYS_ACCEPT4:
                 ret = sys_accept4(a0, compat_ptr(a1), compat_ptr(a[2]), a[3]);
                 break;
diff --git a/net/socket.c b/net/socket.c
index 807935693846..9dff31c9b799 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -683,10 +683,9 @@ void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
 }
 EXPORT_SYMBOL_GPL(sock_recv_ts_and_drops);
 
-static inline int __sock_recvmsg(struct kiocb *iocb, struct socket *sock,
-                                 struct msghdr *msg, size_t size, int flags)
+static inline int __sock_recvmsg_nosec(struct kiocb *iocb, struct socket *sock,
+                                       struct msghdr *msg, size_t size, int flags)
 {
-        int err;
         struct sock_iocb *si = kiocb_to_siocb(iocb);
 
         si->sock = sock;
@@ -695,13 +694,17 @@ static inline int __sock_recvmsg(struct kiocb *iocb, struct socket *sock,
         si->size = size;
         si->flags = flags;
 
-        err = security_socket_recvmsg(sock, msg, size, flags);
-        if (err)
-                return err;
-
         return sock->ops->recvmsg(iocb, sock, msg, size, flags);
 }
 
+static inline int __sock_recvmsg(struct kiocb *iocb, struct socket *sock,
+                                 struct msghdr *msg, size_t size, int flags)
+{
+        int err = security_socket_recvmsg(sock, msg, size, flags);
+
+        return err ?: __sock_recvmsg_nosec(iocb, sock, msg, size, flags);
+}
+
 int sock_recvmsg(struct socket *sock, struct msghdr *msg,
                  size_t size, int flags)
 {
@@ -717,6 +720,21 @@ int sock_recvmsg(struct socket *sock, struct msghdr *msg,
         return ret;
 }
 
+static int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg,
+                              size_t size, int flags)
+{
+        struct kiocb iocb;
+        struct sock_iocb siocb;
+        int ret;
+
+        init_sync_kiocb(&iocb, NULL);
+        iocb.private = &siocb;
+        ret = __sock_recvmsg_nosec(&iocb, sock, msg, size, flags);
+        if (-EIOCBQUEUED == ret)
+                ret = wait_on_sync_kiocb(&iocb);
+        return ret;
+}
+
 int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
                    struct kvec *vec, size_t num, size_t size, int flags)
 {
@@ -1983,22 +2001,15 @@ out:
         return err;
 }
 
-/*
- *      BSD recvmsg interface
- */
-
-SYSCALL_DEFINE3(recvmsg, int, fd, struct msghdr __user *, msg,
-                unsigned int, flags)
+static int __sys_recvmsg(struct socket *sock, struct msghdr __user *msg,
+                         struct msghdr *msg_sys, unsigned flags, int nosec)
 {
         struct compat_msghdr __user *msg_compat =
             (struct compat_msghdr __user *)msg;
-        struct socket *sock;
         struct iovec iovstack[UIO_FASTIOV];
         struct iovec *iov = iovstack;
-        struct msghdr msg_sys;
         unsigned long cmsg_ptr;
         int err, iov_size, total_len, len;
-        int fput_needed;
 
         /* kernel mode address */
         struct sockaddr_storage addr;
@@ -2008,27 +2019,23 @@ SYSCALL_DEFINE3(recvmsg, int, fd, struct msghdr __user *, msg,
         int __user *uaddr_len;
 
         if (MSG_CMSG_COMPAT & flags) {
-                if (get_compat_msghdr(&msg_sys, msg_compat))
+                if (get_compat_msghdr(msg_sys, msg_compat))
                         return -EFAULT;
         }
-        else if (copy_from_user(&msg_sys, msg, sizeof(struct msghdr)))
+        else if (copy_from_user(msg_sys, msg, sizeof(struct msghdr)))
                 return -EFAULT;
 
-        sock = sockfd_lookup_light(fd, &err, &fput_needed);
-        if (!sock)
-                goto out;
-
         err = -EMSGSIZE;
-        if (msg_sys.msg_iovlen > UIO_MAXIOV)
-                goto out_put;
+        if (msg_sys->msg_iovlen > UIO_MAXIOV)
+                goto out;
 
         /* Check whether to allocate the iovec area */
         err = -ENOMEM;
-        iov_size = msg_sys.msg_iovlen * sizeof(struct iovec);
-        if (msg_sys.msg_iovlen > UIO_FASTIOV) {
+        iov_size = msg_sys->msg_iovlen * sizeof(struct iovec);
+        if (msg_sys->msg_iovlen > UIO_FASTIOV) {
                 iov = sock_kmalloc(sock->sk, iov_size, GFP_KERNEL);
                 if (!iov)
-                        goto out_put;
+                        goto out;
         }
 
         /*
@@ -2036,46 +2043,47 @@ SYSCALL_DEFINE3(recvmsg, int, fd, struct msghdr __user *, msg,
          *      kernel msghdr to use the kernel address space)
          */
 
-        uaddr = (__force void __user *)msg_sys.msg_name;
+        uaddr = (__force void __user *)msg_sys->msg_name;
         uaddr_len = COMPAT_NAMELEN(msg);
         if (MSG_CMSG_COMPAT & flags) {
-                err = verify_compat_iovec(&msg_sys, iov,
+                err = verify_compat_iovec(msg_sys, iov,
                                           (struct sockaddr *)&addr,
                                           VERIFY_WRITE);
         } else
-                err = verify_iovec(&msg_sys, iov,
+                err = verify_iovec(msg_sys, iov,
                                    (struct sockaddr *)&addr,
                                    VERIFY_WRITE);
         if (err < 0)
                 goto out_freeiov;
         total_len = err;
 
-        cmsg_ptr = (unsigned long)msg_sys.msg_control;
-        msg_sys.msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
+        cmsg_ptr = (unsigned long)msg_sys->msg_control;
+        msg_sys->msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
 
         if (sock->file->f_flags & O_NONBLOCK)
                 flags |= MSG_DONTWAIT;
-        err = sock_recvmsg(sock, &msg_sys, total_len, flags);
+        err = (nosec ? sock_recvmsg_nosec : sock_recvmsg)(sock, msg_sys,
+                                                          total_len, flags);
         if (err < 0)
                 goto out_freeiov;
         len = err;
 
         if (uaddr != NULL) {
                 err = move_addr_to_user((struct sockaddr *)&addr,
-                                        msg_sys.msg_namelen, uaddr,
+                                        msg_sys->msg_namelen, uaddr,
                                         uaddr_len);
                 if (err < 0)
                         goto out_freeiov;
         }
-        err = __put_user((msg_sys.msg_flags & ~MSG_CMSG_COMPAT),
+        err = __put_user((msg_sys->msg_flags & ~MSG_CMSG_COMPAT),
                          COMPAT_FLAGS(msg));
         if (err)
                 goto out_freeiov;
         if (MSG_CMSG_COMPAT & flags)
-                err = __put_user((unsigned long)msg_sys.msg_control - cmsg_ptr,
+                err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
                                  &msg_compat->msg_controllen);
         else
-                err = __put_user((unsigned long)msg_sys.msg_control - cmsg_ptr,
+                err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
                                  &msg->msg_controllen);
         if (err)
                 goto out_freeiov;
@@ -2084,21 +2092,150 @@ SYSCALL_DEFINE3(recvmsg, int, fd, struct msghdr __user *, msg,
 out_freeiov:
         if (iov != iovstack)
                 sock_kfree_s(sock->sk, iov, iov_size);
-out_put:
+out:
+        return err;
+}
+
+/*
+ *      BSD recvmsg interface
+ */
+
+SYSCALL_DEFINE3(recvmsg, int, fd, struct msghdr __user *, msg,
+                unsigned int, flags)
+{
+        int fput_needed, err;
+        struct msghdr msg_sys;
+        struct socket *sock = sockfd_lookup_light(fd, &err, &fput_needed);
+
+        if (!sock)
+                goto out;
+
+        err = __sys_recvmsg(sock, msg, &msg_sys, flags, 0);
+
         fput_light(sock->file, fput_needed);
 out:
         return err;
 }
 
-#ifdef __ARCH_WANT_SYS_SOCKETCALL
+/*
+ *     Linux recvmmsg interface
+ */
+
+int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
+                   unsigned int flags, struct timespec *timeout)
+{
+        int fput_needed, err, datagrams;
+        struct socket *sock;
+        struct mmsghdr __user *entry;
+        struct msghdr msg_sys;
+        struct timespec end_time;
+
+        if (timeout &&
+            poll_select_set_timeout(&end_time, timeout->tv_sec,
+                                    timeout->tv_nsec))
+                return -EINVAL;
+
+        datagrams = 0;
+
+        sock = sockfd_lookup_light(fd, &err, &fput_needed);
+        if (!sock)
+                return err;
+
+        err = sock_error(sock->sk);
+        if (err)
+                goto out_put;
+
+        entry = mmsg;
+
+        while (datagrams < vlen) {
+                /*
+                 * No need to ask LSM for more than the first datagram.
+                 */
+                err = __sys_recvmsg(sock, (struct msghdr __user *)entry,
+                                    &msg_sys, flags, datagrams);
+                if (err < 0)
+                        break;
+                err = put_user(err, &entry->msg_len);
+                if (err)
+                        break;
+                ++entry;
+                ++datagrams;
+
+                if (timeout) {
+                        ktime_get_ts(timeout);
+                        *timeout = timespec_sub(end_time, *timeout);
+                        if (timeout->tv_sec < 0) {
+                                timeout->tv_sec = timeout->tv_nsec = 0;
+                                break;
+                        }
+
+                        /* Timeout, return less than vlen datagrams */
+                        if (timeout->tv_nsec == 0 && timeout->tv_sec == 0)
+                                break;
+                }
+
+                /* Out of band data, return right away */
+                if (msg_sys.msg_flags & MSG_OOB)
+                        break;
+        }
+
+out_put:
+        fput_light(sock->file, fput_needed);
 
+        if (err == 0)
+                return datagrams;
+
+        if (datagrams != 0) {
+                /*
+                 * We may return less entries than requested (vlen) if the
+                 * sock is non block and there aren't enough datagrams...
+                 */
+                if (err != -EAGAIN) {
+                        /*
+                         * ... or  if recvmsg returns an error after we
+                         * received some datagrams, where we record the
+                         * error to return on the next call or if the
+                         * app asks about it using getsockopt(SO_ERROR).
+                         */
+                        sock->sk->sk_err = -err;
+                }
+
+                return datagrams;
+        }
+
+        return err;
+}
+
+SYSCALL_DEFINE5(recvmmsg, int, fd, struct mmsghdr __user *, mmsg,
+                unsigned int, vlen, unsigned int, flags,
+                struct timespec __user *, timeout)
+{
+        int datagrams;
+        struct timespec timeout_sys;
+
+        if (!timeout)
+                return __sys_recvmmsg(fd, mmsg, vlen, flags, NULL);
+
+        if (copy_from_user(&timeout_sys, timeout, sizeof(timeout_sys)))
+                return -EFAULT;
+
+        datagrams = __sys_recvmmsg(fd, mmsg, vlen, flags, &timeout_sys);
+
+        if (datagrams > 0 &&
+            copy_to_user(timeout, &timeout_sys, sizeof(timeout_sys)))
+                datagrams = -EFAULT;
+
+        return datagrams;
+}
+
+#ifdef __ARCH_WANT_SYS_SOCKETCALL
 /* Argument list sizes for sys_socketcall */
 #define AL(x) ((x) * sizeof(unsigned long))
-static const unsigned char nargs[19]={
+static const unsigned char nargs[20] = {
         AL(0),AL(3),AL(3),AL(3),AL(2),AL(3),
         AL(3),AL(3),AL(4),AL(4),AL(4),AL(6),
         AL(6),AL(2),AL(5),AL(5),AL(3),AL(3),
-        AL(4)
+        AL(4),AL(5)
 };
 
 #undef AL
@@ -2118,7 +2255,7 @@ SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
         int err;
         unsigned int len;
 
-        if (call < 1 || call > SYS_ACCEPT4)
+        if (call < 1 || call > SYS_RECVMMSG)
                 return -EINVAL;
 
         len = nargs[call];
@@ -2196,6 +2333,10 @@ SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
         case SYS_RECVMSG:
                 err = sys_recvmsg(a0, (struct msghdr __user *)a1, a[2]);
                 break;
+        case SYS_RECVMMSG:
+                err = sys_recvmmsg(a0, (struct mmsghdr __user *)a1, a[2], a[3],
+                                   (struct timespec __user *)a[4]);
+                break;
         case SYS_ACCEPT4:
                 err = sys_accept4(a0, (struct sockaddr __user *)a1,
                                   (int __user *)a[2], a[3]);