syscall: add Mmap, Munmap on Linux, FreeBSD, OS X

* tweak mksyscall*.pl to be more gofmt-compatible.
* add mkall.sh -syscalls option.
* add sys/mman.h constants on OS X

R=r, eds, niemeyer
CC=golang-dev
https://golang.org/cl/4369044

.hgignore

@@ -21,6 +21,8 @@ _cgo_*
 _obj
 _test
 _testmain.go
+build.out
+test.out
 y.tab.[ch]
 doc/htmlgen
 doc/codelab/wiki/*.bin

src/pkg/syscall/asm_darwin_386.s

@@ -61,6 +61,36 @@ ok6:
 	CALL	runtime·exitsyscall(SB)
 	RET
 
+TEXT	·Syscall9(SB),7,$0
+	CALL	runtime·entersyscall(SB)
+	MOVL	4(SP), AX	// syscall entry
+	// slide args down on top of system call number
+	LEAL		8(SP), SI
+	LEAL		4(SP), DI
+	CLD
+	MOVSL
+	MOVSL
+	MOVSL
+	MOVSL
+	MOVSL
+	MOVSL
+	MOVSL
+	MOVSL
+	MOVSL
+	INT	$0x80
+	JAE	ok9
+	MOVL	$-1, 44(SP)	// r1
+	MOVL	$-1, 48(SP)	// r2
+	MOVL	AX, 52(SP)		// errno
+	CALL	runtime·exitsyscall(SB)
+	RET
+ok9:
+	MOVL	AX, 44(SP)	// r1
+	MOVL	DX, 48(SP)	// r2
+	MOVL	$0, 52(SP)	// errno
+	CALL	runtime·exitsyscall(SB)
+	RET
+
 TEXT ·RawSyscall(SB),7,$0
 	MOVL	4(SP), AX	// syscall entry
 	// slide args down on top of system call number

src/pkg/syscall/mkall.sh

@@ -81,6 +81,13 @@ mkerrors="./mkerrors.sh"
 run="sh"
 
 case "$1" in
+-syscalls)
+	for i in zsyscall*go
+	do
+		sed 1q $i | sed 's;^// ;;' | sh | gofmt >_$i && mv _$i $i
+	done
+	exit 0
+	;;
 -n)
 	run="cat"
 	shift

src/pkg/syscall/mkerrors.sh

@@ -45,6 +45,7 @@ includes_Darwin='
 #include <sys/socket.h>
 #include <sys/sockio.h>
 #include <sys/sysctl.h>
+#include <sys/mman.h>
 #include <sys/wait.h>
 #include <net/if.h>
 #include <net/route.h>

src/pkg/syscall/mksyscall.pl

@@ -143,6 +143,11 @@ while(<>) {
 		while(@args < 6) {
 			push @args, "0";
 		}
+	} elsif(@args <= 9) {
+		$asm .= "9";
+		while(@args < 9) {
+			push @args, "0";
+		}
 	} else {
 		print STDERR "$ARGV:$.: too many arguments to system call\n";
 	}
@@ -204,7 +209,7 @@ while(<>) {
 	if ($plan9 && $ret[2] eq "e1") {
 		$text .= "\terr = nil\n";
 		$text .= "\tif int(r0) == -1 {\n";
-		$text .= "\t\t err = NewError(e1)\n";
+		$text .= "\t\terr = NewError(e1)\n";
 		$text .= "\t}\n";
 	}
 

src/pkg/syscall/mksyscall_windows.pl

@@ -119,7 +119,14 @@ while(<>) {
 	$vars .= sprintf "\t%s = getSysProcAddr(%s, \"%s\")\n", $sysvarname, $modvname, $sysname;
 
 	# Go function header.
-	$text .= sprintf "func %s(%s) (%s) {\n", $func, join(', ', @in), join(', ', @out);
+	my $out = join(', ', @out);
+	if($out ne "") {
+		$out = " ($out)";
+	}
+	if($text ne "") {
+		$text .= "\n"
+	}
+	$text .= sprintf "func %s(%s)%s {\n", $func, join(', ', @in), $out;
 
 	# Prepare arguments to Syscall.
 	my @args = ();
@@ -232,6 +239,7 @@ while(<>) {
 				$failexpr = "$name $failcond";
 			}
 		}
+		$failexpr =~ s/(=)([0-9A-Za-z\-+])/\1 \2/;  # gofmt compatible
 		if($name eq "errno") {
 			# Set errno to "last error" only if returned value indicate failure
 			$body .= "\tif $failexpr {\n";
@@ -259,7 +267,7 @@ while(<>) {
 	}
 
 	$text .= "\treturn\n";
-	$text .= "}\n\n";
+	$text .= "}\n";
 }
 
 if($errors) {

src/pkg/syscall/syscall.go

@@ -13,6 +13,11 @@
 // errno is an operating system error number describing the failure.
 package syscall
 
+import (
+	"sync"
+	"unsafe"
+)
+
 // StringByteSlice returns a NUL-terminated slice of bytes
 // containing the text of s.
 func StringByteSlice(s string) []byte {
@@ -28,3 +33,63 @@ func StringBytePtr(s string) *byte { return &StringByteSlice(s)[0] }
 // Single-word zero for use when we need a valid pointer to 0 bytes.
 // See mksyscall.sh.
 var _zero uintptr
+
+// Mmap manager, for use by operating system-specific implementations.
+
+type mmapper struct {
+	sync.Mutex
+	active map[*byte][]byte // active mappings; key is last byte in mapping
+	mmap   func(addr, length uintptr, prot, flags, fd int, offset int64) (uintptr, int)
+	munmap func(addr uintptr, length uintptr) int
+}
+
+func (m *mmapper) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, errno int) {
+	if length <= 0 {
+		return nil, EINVAL
+	}
+
+	// Map the requested memory.
+	addr, errno := m.mmap(0, uintptr(length), prot, flags, fd, offset)
+	if errno != 0 {
+		return nil, errno
+	}
+
+	// Slice memory layout
+	var sl = struct {
+		addr uintptr
+		len  int
+		cap  int
+	}{addr, length, length}
+
+	// Use unsafe to turn sl into a []byte.
+	b := *(*[]byte)(unsafe.Pointer(&sl))
+
+	// Register mapping in m and return it.
+	p := &b[cap(b)-1]
+	m.Lock()
+	defer m.Unlock()
+	m.active[p] = b
+	return b, 0
+}
+
+func (m *mmapper) Munmap(data []byte) (errno int) {
+	if len(data) == 0 || len(data) != cap(data) {
+		return EINVAL
+	}
+
+	// Find the base of the mapping.
+	p := &data[cap(data)-1]
+	m.Lock()
+	defer m.Unlock()
+	b := m.active[p]
+	if b == nil || &b[0] != &data[0] {
+		return EINVAL
+	}
+
+	// Unmap the memory and update m.
+	if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); errno != 0 {
+		return errno
+	}
+	m.active[p] = nil, false
+	return 0
+}

src/pkg/syscall/syscall_bsd.go

@@ -598,5 +598,21 @@ func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (errno int) {
 //	Madvise(addr *byte, len int, behav int) (errno int)
 //	Mprotect(addr *byte, len int, prot int) (errno int)
 //	Msync(addr *byte, len int, flags int) (errno int)
-//	Munmap(addr *byte, len int) (errno int)
 //	Ptrace(req int, pid int, addr uintptr, data int) (ret uintptr, errno int)
+
+//sys	mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, errno int)
+//sys	munmap(addr uintptr, length uintptr) (errno int)
+
+var mapper = &mmapper{
+	active: make(map[*byte][]byte),
+	mmap:   mmap,
+	munmap: munmap,
+}
+
+func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, errno int) {
+	return mapper.Mmap(fd, offset, length, prot, flags)
+}
+
+func Munmap(b []byte) (errno int) {
+	return mapper.Munmap(b)
+}

src/pkg/syscall/syscall_darwin_386.go

@@ -39,3 +39,5 @@ func SetKevent(k *Kevent_t, fd, mode, flags int) {
 	k.Filter = int16(mode)
 	k.Flags = uint16(flags)
 }
+
+func Syscall9(num, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2, err uintptr) // sic

src/pkg/syscall/syscall_linux.go

@@ -797,6 +797,23 @@ func ParseDirent(buf []byte, max int, names []string) (consumed int, count int,
 //sys	read(fd int, p *byte, np int) (n int, errno int)
 //sys	write(fd int, p *byte, np int) (n int, errno int)
 
+// mmap varies by architecutre; see syscall_linux_*.go.
+//sys	munmap(addr uintptr, length uintptr) (errno int)
+
+var mapper = &mmapper{
+	active: make(map[*byte][]byte),
+	mmap:   mmap,
+	munmap: munmap,
+}
+
+func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, errno int) {
+	return mapper.Mmap(fd, offset, length, prot, flags)
+}
+
+func Munmap(b []byte) (errno int) {
+	return mapper.Munmap(b)
+}
+
 /*
  * Unimplemented
  */

src/pkg/syscall/syscall_linux_386.go

@@ -56,6 +56,16 @@ func NsecToTimeval(nsec int64) (tv Timeval) {
 //sysnb	setgroups(n int, list *_Gid_t) (errno int) = SYS_SETGROUPS32
 //sys	Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, errno int) = SYS__NEWSELECT
 
+//sys	mmap2(addr uintptr, length uintptr, prot int, flags int, fd int, pageOffset uintptr) (xaddr uintptr, errno int)
+
+func mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, errno int) {
+	page := uintptr(offset / 4096)
+	if offset != int64(page)*4096 {
+		return 0, EINVAL
+	}
+	return mmap2(addr, length, prot, flags, fd, page)
+}
+
 // Underlying system call writes to newoffset via pointer.
 // Implemented in assembly to avoid allocation.
 func Seek(fd int, offset int64, whence int) (newoffset int64, errno int)

src/pkg/syscall/syscall_linux_amd64.go

@@ -50,6 +50,7 @@ package syscall
 //sys	sendto(s int, buf []byte, flags int, to uintptr, addrlen _Socklen) (errno int)
 //sys	recvmsg(s int, msg *Msghdr, flags int) (n int, errno int)
 //sys	sendmsg(s int, msg *Msghdr, flags int) (errno int)
+//sys	mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, errno int)
 
 func Getpagesize() int { return 4096 }
 

src/pkg/syscall/syscall_linux_arm.go

@@ -98,6 +98,16 @@ func Seek(fd int, offset int64, whence int) (newoffset int64, errno int)
 //sysnb	Gettimeofday(tv *Timeval) (errno int)
 //sysnb	Time(t *Time_t) (tt Time_t, errno int)
 
+//sys	mmap2(addr uintptr, length uintptr, prot int, flags int, fd int, pageOffset uintptr) (xaddr uintptr, errno int)
+
+func mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, errno int) {
+	page := uintptr(offset / 4096)
+	if offset != int64(page)*4096 {
+		return 0, EINVAL
+	}
+	return mmap2(addr, length, prot, flags, fd, page)
+}
+
 // TODO(kaib): add support for tracing
 func (r *PtraceRegs) PC() uint64 { return 0 }
 

src/pkg/syscall/zerrors_darwin_386.go

@@ -196,7 +196,6 @@ const (
 	F_GETLK                     = 0x7
 	F_GETOWN                    = 0x5
 	F_GETPATH                   = 0x32
-	F_GETPROTECTIONCLASS        = 0x3e
 	F_GLOBAL_NOCACHE            = 0x37
 	F_LOG2PHYS                  = 0x31
 	F_MARKDEPENDENCY            = 0x3c
@@ -213,7 +212,6 @@ const (
 	F_SETLK                     = 0x8
 	F_SETLKW                    = 0x9
 	F_SETOWN                    = 0x6
-	F_SETPROTECTIONCLASS        = 0x3f
 	F_SETSIZE                   = 0x2b
 	F_THAW_FS                   = 0x36
 	F_UNLCK                     = 0x2
@@ -461,6 +459,20 @@ const (
 	IP_TOS                      = 0x3
 	IP_TRAFFIC_MGT_BACKGROUND   = 0x41
 	IP_TTL                      = 0x4
+	MAP_ANON                    = 0x1000
+	MAP_COPY                    = 0x2
+	MAP_FILE                    = 0
+	MAP_FIXED                   = 0x10
+	MAP_HASSEMAPHORE            = 0x200
+	MAP_NOCACHE                 = 0x400
+	MAP_NOEXTEND                = 0x100
+	MAP_NORESERVE               = 0x40
+	MAP_PRIVATE                 = 0x2
+	MAP_RENAME                  = 0x20
+	MAP_RESERVED0080            = 0x80
+	MAP_SHARED                  = 0x1
+	MCL_CURRENT                 = 0x1
+	MCL_FUTURE                  = 0x2
 	MSG_CTRUNC                  = 0x20
 	MSG_DONTROUTE               = 0x4
 	MSG_DONTWAIT                = 0x80
@@ -477,6 +489,11 @@ const (
 	MSG_TRUNC                   = 0x10
 	MSG_WAITALL                 = 0x40
 	MSG_WAITSTREAM              = 0x200
+	MS_ASYNC                    = 0x1
+	MS_DEACTIVATE               = 0x8
+	MS_INVALIDATE               = 0x2
+	MS_KILLPAGES                = 0x4
+	MS_SYNC                     = 0x10
 	NAME_MAX                    = 0xff
 	NET_RT_DUMP                 = 0x1
 	NET_RT_DUMP2                = 0x7
@@ -509,6 +526,10 @@ const (
 	O_SYNC                      = 0x80
 	O_TRUNC                     = 0x400
 	O_WRONLY                    = 0x1
+	PROT_EXEC                   = 0x4
+	PROT_NONE                   = 0
+	PROT_READ                   = 0x1
+	PROT_WRITE                  = 0x2
 	RTAX_AUTHOR                 = 0x6
 	RTAX_BRD                    = 0x7
 	RTAX_DST                    = 0
@@ -535,7 +556,6 @@ const (
 	RTF_DYNAMIC                 = 0x10
 	RTF_GATEWAY                 = 0x2
 	RTF_HOST                    = 0x4
-	RTF_IFREF                   = 0x4000000
 	RTF_IFSCOPE                 = 0x1000000
 	RTF_LLINFO                  = 0x400
 	RTF_LOCAL                   = 0x200000
@@ -629,7 +649,6 @@ const (
 	SIOCDIFADDR                 = 0x80206919
 	SIOCDIFPHYADDR              = 0x80206941
 	SIOCDLIFADDR                = 0x8118691f
-	SIOCGDRVSPEC                = 0xc01c697b
 	SIOCGETSGCNT                = 0xc014721c
 	SIOCGETVIFCNT               = 0xc014721b
 	SIOCGETVLAN                 = 0xc020697f
@@ -661,10 +680,8 @@ const (
 	SIOCGLOWAT                  = 0x40047303
 	SIOCGPGRP                   = 0x40047309
 	SIOCIFCREATE                = 0xc0206978
-	SIOCIFCREATE2               = 0xc020697a
 	SIOCIFDESTROY               = 0x80206979
 	SIOCRSLVMULTI               = 0xc008693b
-	SIOCSDRVSPEC                = 0x801c697b
 	SIOCSETVLAN                 = 0x8020697e
 	SIOCSHIWAT                  = 0x80047300
 	SIOCSIFADDR                 = 0x8020690c

src/pkg/syscall/zerrors_darwin_amd64.go

@@ -196,7 +196,6 @@ const (
 	F_GETLK                     = 0x7
 	F_GETOWN                    = 0x5
 	F_GETPATH                   = 0x32
-	F_GETPROTECTIONCLASS        = 0x3e
 	F_GLOBAL_NOCACHE            = 0x37
 	F_LOG2PHYS                  = 0x31
 	F_MARKDEPENDENCY            = 0x3c
@@ -213,7 +212,6 @@ const (
 	F_SETLK                     = 0x8
 	F_SETLKW                    = 0x9
 	F_SETOWN                    = 0x6
-	F_SETPROTECTIONCLASS        = 0x3f
 	F_SETSIZE                   = 0x2b
 	F_THAW_FS                   = 0x36
 	F_UNLCK                     = 0x2
@@ -461,6 +459,20 @@ const (
 	IP_TOS                      = 0x3
 	IP_TRAFFIC_MGT_BACKGROUND   = 0x41
 	IP_TTL                      = 0x4
+	MAP_ANON                    = 0x1000
+	MAP_COPY                    = 0x2
+	MAP_FILE                    = 0
+	MAP_FIXED                   = 0x10
+	MAP_HASSEMAPHORE            = 0x200
+	MAP_NOCACHE                 = 0x400
+	MAP_NOEXTEND                = 0x100
+	MAP_NORESERVE               = 0x40
+	MAP_PRIVATE                 = 0x2
+	MAP_RENAME                  = 0x20
+	MAP_RESERVED0080            = 0x80
+	MAP_SHARED                  = 0x1
+	MCL_CURRENT                 = 0x1
+	MCL_FUTURE                  = 0x2
 	MSG_CTRUNC                  = 0x20
 	MSG_DONTROUTE               = 0x4
 	MSG_DONTWAIT                = 0x80
@@ -477,6 +489,11 @@ const (
 	MSG_TRUNC                   = 0x10
 	MSG_WAITALL                 = 0x40
 	MSG_WAITSTREAM              = 0x200
+	MS_ASYNC                    = 0x1
+	MS_DEACTIVATE               = 0x8
+	MS_INVALIDATE               = 0x2
+	MS_KILLPAGES                = 0x4
+	MS_SYNC                     = 0x10
 	NAME_MAX                    = 0xff
 	NET_RT_DUMP                 = 0x1
 	NET_RT_DUMP2                = 0x7
@@ -509,6 +526,10 @@ const (
 	O_SYNC                      = 0x80
 	O_TRUNC                     = 0x400
 	O_WRONLY                    = 0x1
+	PROT_EXEC                   = 0x4
+	PROT_NONE                   = 0
+	PROT_READ                   = 0x1
+	PROT_WRITE                  = 0x2
 	RTAX_AUTHOR                 = 0x6
 	RTAX_BRD                    = 0x7
 	RTAX_DST                    = 0
@@ -535,7 +556,6 @@ const (
 	RTF_DYNAMIC                 = 0x10
 	RTF_GATEWAY                 = 0x2
 	RTF_HOST                    = 0x4
-	RTF_IFREF                   = 0x4000000
 	RTF_IFSCOPE                 = 0x1000000
 	RTF_LLINFO                  = 0x400
 	RTF_LOCAL                   = 0x200000
@@ -629,7 +649,6 @@ const (
 	SIOCDIFADDR                 = 0x80206919
 	SIOCDIFPHYADDR              = 0x80206941
 	SIOCDLIFADDR                = 0x8118691f
-	SIOCGDRVSPEC                = 0xc028697b
 	SIOCGETSGCNT                = 0xc014721c
 	SIOCGETVIFCNT               = 0xc014721b
 	SIOCGETVLAN                 = 0xc020697f
@@ -661,10 +680,8 @@ const (
 	SIOCGLOWAT                  = 0x40047303
 	SIOCGPGRP                   = 0x40047309
 	SIOCIFCREATE                = 0xc0206978
-	SIOCIFCREATE2               = 0xc020697a
 	SIOCIFDESTROY               = 0x80206979
 	SIOCRSLVMULTI               = 0xc010693b
-	SIOCSDRVSPEC                = 0x8028697b
 	SIOCSETVLAN                 = 0x8020697e
 	SIOCSHIWAT                  = 0x80047300
 	SIOCSIFADDR                 = 0x8020690c

src/pkg/syscall/zsyscall_darwin_386.go

@@ -202,6 +202,23 @@ func fcntl(fd int, cmd int, arg int) (val int, errno int) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, errno int) {
+	r0, _, e1 := Syscall9(SYS_MMAP, uintptr(addr), uintptr(length), uintptr(prot), uintptr(flag), uintptr(fd), uintptr(pos), uintptr(pos>>32), 0, 0)
+	ret = uintptr(r0)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func munmap(addr uintptr, length uintptr) (errno int) {
+	_, _, e1 := Syscall(SYS_MUNMAP, uintptr(addr), uintptr(length), 0)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func kill(pid int, signum int, posix int) (errno int) {
 	_, _, e1 := Syscall(SYS_KILL, uintptr(pid), uintptr(signum), uintptr(posix))
 	errno = int(e1)

src/pkg/syscall/zsyscall_darwin_amd64.go

@@ -202,6 +202,23 @@ func fcntl(fd int, cmd int, arg int) (val int, errno int) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, errno int) {
+	r0, _, e1 := Syscall6(SYS_MMAP, uintptr(addr), uintptr(length), uintptr(prot), uintptr(flag), uintptr(fd), uintptr(pos))
+	ret = uintptr(r0)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func munmap(addr uintptr, length uintptr) (errno int) {
+	_, _, e1 := Syscall(SYS_MUNMAP, uintptr(addr), uintptr(length), 0)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func kill(pid int, signum int, posix int) (errno int) {
 	_, _, e1 := Syscall(SYS_KILL, uintptr(pid), uintptr(signum), uintptr(posix))
 	errno = int(e1)

src/pkg/syscall/zsyscall_freebsd_386.go

@@ -202,6 +202,23 @@ func fcntl(fd int, cmd int, arg int) (val int, errno int) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, errno int) {
+	r0, _, e1 := Syscall9(SYS_MMAP, uintptr(addr), uintptr(length), uintptr(prot), uintptr(flag), uintptr(fd), uintptr(pos), uintptr(pos>>32), 0, 0)
+	ret = uintptr(r0)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func munmap(addr uintptr, length uintptr) (errno int) {
+	_, _, e1 := Syscall(SYS_MUNMAP, uintptr(addr), uintptr(length), 0)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func Access(path string, mode uint32) (errno int) {
 	_, _, e1 := Syscall(SYS_ACCESS, uintptr(unsafe.Pointer(StringBytePtr(path))), uintptr(mode), 0)
 	errno = int(e1)

src/pkg/syscall/zsyscall_freebsd_amd64.go

@@ -202,6 +202,23 @@ func fcntl(fd int, cmd int, arg int) (val int, errno int) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, errno int) {
+	r0, _, e1 := Syscall6(SYS_MMAP, uintptr(addr), uintptr(length), uintptr(prot), uintptr(flag), uintptr(fd), uintptr(pos))
+	ret = uintptr(r0)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func munmap(addr uintptr, length uintptr) (errno int) {
+	_, _, e1 := Syscall(SYS_MUNMAP, uintptr(addr), uintptr(length), 0)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func Access(path string, mode uint32) (errno int) {
 	_, _, e1 := Syscall(SYS_ACCESS, uintptr(unsafe.Pointer(StringBytePtr(path))), uintptr(mode), 0)
 	errno = int(e1)

src/pkg/syscall/zsyscall_linux_386.go

@@ -765,6 +765,14 @@ func write(fd int, p *byte, np int) (n int, errno int) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func munmap(addr uintptr, length uintptr) (errno int) {
+	_, _, e1 := Syscall(SYS_MUNMAP, uintptr(addr), uintptr(length), 0)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func Chown(path string, uid int, gid int) (errno int) {
 	_, _, e1 := Syscall(SYS_CHOWN32, uintptr(unsafe.Pointer(StringBytePtr(path))), uintptr(uid), uintptr(gid))
 	errno = int(e1)
@@ -1006,6 +1014,15 @@ func Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func mmap2(addr uintptr, length uintptr, prot int, flags int, fd int, pageOffset uintptr) (xaddr uintptr, errno int) {
+	r0, _, e1 := Syscall6(SYS_MMAP2, uintptr(addr), uintptr(length), uintptr(prot), uintptr(flags), uintptr(fd), uintptr(pageOffset))
+	xaddr = uintptr(r0)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func Gettimeofday(tv *Timeval) (errno int) {
 	_, _, e1 := RawSyscall(SYS_GETTIMEOFDAY, uintptr(unsafe.Pointer(tv)), 0, 0)
 	errno = int(e1)