syscall: add support for GOARCH=mips{,le}

Change-Id: I39a46b2a9412981db1780b688a86fec791f68b6f
Reviewed-on: https://go-review.googlesource.com/31488
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

src/syscall/asm_linux_mipsx.s

+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux
+// +build mips mipsle
+
+#include "textflag.h"
+#include "funcdata.h"
+
+//
+// System calls for mips, Linux
+//
+
+// func Syscall(trap uintptr, a1, a2, a3 uintptr) (r1, r2, err uintptr);
+
+TEXT	·Syscall(SB),NOSPLIT,$0-28
+	JAL	runtime·entersyscall(SB)
+	MOVW	a1+4(FP), R4
+	MOVW	a2+8(FP), R5
+	MOVW	a3+12(FP), R6
+	MOVW	R0, R7
+	MOVW	trap+0(FP), R2	// syscall entry
+	SYSCALL
+	BEQ	R7, ok
+	MOVW	$-1, R1
+	MOVW	R1, r1+16(FP)	// r1
+	MOVW	R0, r2+20(FP)	// r2
+	MOVW	R2, err+24(FP)	// errno
+	JAL	runtime·exitsyscall(SB)
+	RET
+ok:
+	MOVW	R2, r1+16(FP)	// r1
+	MOVW	R3, r2+20(FP)	// r2
+	MOVW	R0, err+24(FP)	// errno
+	JAL	runtime·exitsyscall(SB)
+	RET
+
+
+// func Syscall6(trap trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr);
+// 5th and 6th arg go at sp+16, sp+20.
+// Note that frame size of 20 means that 24 bytes gets reserved on stack.
+TEXT ·Syscall6(SB),NOSPLIT,$20-40
+	NO_LOCAL_POINTERS
+	JAL	runtime·entersyscall(SB)
+	MOVW	a1+4(FP), R4
+	MOVW	a2+8(FP), R5
+	MOVW	a3+12(FP), R6
+	MOVW	a4+16(FP), R7
+	MOVW	a5+20(FP), R8
+	MOVW	a6+24(FP), R9
+	MOVW	R8, 16(R29)
+	MOVW	R9, 20(R29)
+	MOVW	trap+0(FP), R2	// syscall entry
+	SYSCALL
+	BEQ	R7, ok6
+	MOVW	$-1, R1
+	MOVW	R1, r1+28(FP)	// r1
+	MOVW	R0, r2+32(FP)	// r2
+	MOVW	R2, err+36(FP)	// errno
+	JAL	runtime·exitsyscall(SB)
+	RET
+ok6:
+	MOVW	R2, r1+28(FP)	// r1
+	MOVW	R3, r2+32(FP)	// r2
+	MOVW	R0, err+36(FP)	// errno
+	JAL	runtime·exitsyscall(SB)
+	RET
+
+// func Syscall9(trap trap, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2, err uintptr);
+// Actually Syscall8 but the rest of the code expects it to be named Syscall9.
+TEXT ·Syscall9(SB),NOSPLIT,$28-52
+	NO_LOCAL_POINTERS
+	JAL	runtime·entersyscall(SB)
+	MOVW	a1+4(FP), R4
+	MOVW	a2+8(FP), R5
+	MOVW	a3+12(FP), R6
+	MOVW	a4+16(FP), R7
+	MOVW	a5+20(FP), R8
+	MOVW	a6+24(FP), R9
+	MOVW	a7+28(FP), R10
+	MOVW	a8+32(FP), R11
+	MOVW	R8, 16(R29)
+	MOVW	R9, 20(R29)
+	MOVW	R10, 24(R29)
+	MOVW	R11, 28(R29)
+	MOVW	trap+0(FP), R2	// syscall entry
+	SYSCALL
+	BEQ	R7, ok9
+	MOVW	$-1, R1
+	MOVW	R1, r1+28(FP)	// r1
+	MOVW	R0, r2+32(FP)	// r2
+	MOVW	R2, err+36(FP)	// errno
+	JAL	runtime·exitsyscall(SB)
+	RET
+ok9:
+	MOVW	R2, r1+28(FP)	// r1
+	MOVW	R3, r2+32(FP)	// r2
+	MOVW	R0, err+36(FP)	// errno
+	JAL	runtime·exitsyscall(SB)
+	RET
+
+TEXT ·RawSyscall(SB),NOSPLIT,$24-28
+	MOVW	a1+4(FP), R4
+	MOVW	a2+8(FP), R5
+	MOVW	a3+12(FP), R6
+	MOVW	trap+0(FP), R2	// syscall entry
+	SYSCALL
+	BEQ	R7, ok1
+	MOVW	$-1, R1
+	MOVW	R1, r1+16(FP)	// r1
+	MOVW	R0, r2+20(FP)	// r2
+	MOVW	R2, err+24(FP)	// errno
+	RET
+ok1:
+	MOVW	R2, r1+16(FP)	// r1
+	MOVW	R3, r2+20(FP)	// r2
+	MOVW	R0, err+24(FP)	// errno
+	RET
+
+TEXT ·RawSyscall6(SB),NOSPLIT,$20-40
+	MOVW	a1+4(FP), R4
+	MOVW	a2+8(FP), R5
+	MOVW	a3+12(FP), R6
+	MOVW	a4+16(FP), R7
+	MOVW	a5+20(FP), R8
+	MOVW	a6+24(FP), R9
+	MOVW	R8, 16(R29)
+	MOVW	R9, 20(R29)
+	MOVW	trap+0(FP), R2	// syscall entry
+	SYSCALL
+	BEQ	R7, ok2
+	MOVW	$-1, R1
+	MOVW	R1, r1+28(FP)	// r1
+	MOVW	R0, r2+32(FP)	// r2
+	MOVW	R2, err+36(FP)	// errno
+	RET
+ok2:
+	MOVW	R2, r1+28(FP)	// r1
+	MOVW	R3, r2+32(FP)	// r2
+	MOVW	R0, err+36(FP)	// errno
+	RET

src/syscall/endian_big.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 //
-// +build ppc64 s390x mips64
+// +build ppc64 s390x mips mips64
 
 package syscall
 

src/syscall/endian_little.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 //
-// +build 386 amd64 amd64p32 arm arm64 ppc64le mips64le
+// +build 386 amd64 amd64p32 arm arm64 ppc64le mips64le mipsle
 
 package syscall
 

src/syscall/flock_linux_32bit.go

-// +build linux,386 linux,arm
+// +build linux,386 linux,arm linux,mips linux,mipsle
 
 // Copyright 2014 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style

src/syscall/mksysnum_linux.pl

@@ -16,21 +16,28 @@ package syscall
 const(
 EOF
 
+my $offset = 0;
+
 sub fmt {
 	my ($name, $num) = @_;
 	if($num > 999){
-		# ignore depricated syscalls that are no longer implemented
+		# ignore deprecated syscalls that are no longer implemented
 		# https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/include/uapi/asm-generic/unistd.h?id=refs/heads/master#n716
 		return;
 	}
 	$name =~ y/a-z/A-Z/;
+	$num = $num + $offset;
 	print "	SYS_$name = $num;\n";
 }
 
 my $prev;
 open(GCC, "gcc -E -dD $ARGV[0] |") || die "can't run gcc";
 while(<GCC>){
-	if(/^#define __NR_syscalls\s+/) {
+	if(/^#define __NR_Linux\s+([0-9]+)/){
+		# mips/mips64: extract offset
+		$offset = $1;
+	}
+	elsif(/^#define __NR_syscalls\s+/) {
 		# ignore redefinitions of __NR_syscalls
 	}
 	elsif(/^#define __NR_(\w+)\s+([0-9]+)/){
@@ -44,6 +51,9 @@ while(<GCC>){
 	elsif(/^#define __NR_(\w+)\s+\(\w+\+\s*([0-9]+)\)/){
 		fmt($1, $prev+$2)
 	}
+	elsif(/^#define __NR_(\w+)\s+\(__NR_Linux \+ ([0-9]+)/){
+		fmt($1, $2);
+	}
 }
 
 print <<EOF;

src/syscall/syscall_linux_mipsx.go

+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux
+// +build mips mipsle
+
+package syscall
+
+import "unsafe"
+
+const (
+	_SYS_dup       = SYS_DUP2
+	_SYS_getdents  = SYS_GETDENTS64
+	_SYS_setgroups = SYS_SETGROUPS
+)
+
+func Syscall9(trap, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2 uintptr, err Errno)
+
+//sys	Dup2(oldfd int, newfd int) (err error)
+//sys	Fchown(fd int, uid int, gid int) (err error)
+//sys	Ftruncate(fd int, length int64) (err error) = SYS_FTRUNCATE64
+//sysnb	Getegid() (egid int)
+//sysnb	Geteuid() (euid int)
+//sysnb	Getgid() (gid int)
+//sysnb	Getuid() (uid int)
+//sys	Lchown(path string, uid int, gid int) (err error)
+//sys	Listen(s int, n int) (err error)
+//sys	Pread(fd int, p []byte, offset int64) (n int, err error) = SYS_PREAD64
+//sys	Pwrite(fd int, p []byte, offset int64) (n int, err error) = SYS_PWRITE64
+//sys	Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err error) = SYS__NEWSELECT
+//sys	sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) = SYS_SENDFILE64
+//sys	Setfsgid(gid int) (err error)
+//sys	Setfsuid(uid int) (err error)
+//sysnb	Setregid(rgid int, egid int) (err error)
+//sysnb	Setresgid(rgid int, egid int, sgid int) (err error)
+//sysnb	Setresuid(ruid int, euid int, suid int) (err error)
+
+//sysnb	Setreuid(ruid int, euid int) (err error)
+//sys	Shutdown(fd int, how int) (err error)
+//sys	Splice(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n int64, err error)
+
+//sys	SyncFileRange(fd int, off int64, n int64, flags int) (err error)
+//sys	Truncate(path string, length int64) (err error) = SYS_TRUNCATE64
+//sys	accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error)
+//sys	accept4(s int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (fd int, err error)
+//sys	bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
+//sys	connect(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
+//sysnb	getgroups(n int, list *_Gid_t) (nn int, err error)
+//sysnb	setgroups(n int, list *_Gid_t) (err error)
+//sys	getsockopt(s int, level int, name int, val unsafe.Pointer, vallen *_Socklen) (err error)
+//sys	setsockopt(s int, level int, name int, val unsafe.Pointer, vallen uintptr) (err error)
+//sysnb	socket(domain int, typ int, proto int) (fd int, err error)
+//sysnb	socketpair(domain int, typ int, proto int, fd *[2]int32) (err error)
+//sysnb	getpeername(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
+//sysnb	getsockname(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
+//sys	recvfrom(fd int, p []byte, flags int, from *RawSockaddrAny, fromlen *_Socklen) (n int, err error)
+//sys	sendto(s int, buf []byte, flags int, to unsafe.Pointer, addrlen _Socklen) (err error)
+//sys	recvmsg(s int, msg *Msghdr, flags int) (n int, err error)
+//sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error)
+
+//sysnb	InotifyInit() (fd int, err error)
+//sys	Ioperm(from int, num int, on int) (err error)
+//sys	Iopl(level int) (err error)
+
+//sysnb	Gettimeofday(tv *Timeval) (err error)
+//sysnb	Time(t *Time_t) (tt Time_t, err error)
+
+//sys	Lstat(path string, stat *Stat_t) (err error) = SYS_LSTAT64
+//sys	Fstat(fd int, stat *Stat_t) (err error) = SYS_FSTAT64
+//sys	Stat(path string, stat *Stat_t) (err error) = SYS_STAT64
+
+func Fstatfs(fd int, buf *Statfs_t) (err error) {
+	_, _, e := Syscall(SYS_FSTATFS64, uintptr(fd), unsafe.Sizeof(*buf), uintptr(unsafe.Pointer(buf)))
+	use(unsafe.Pointer(buf))
+	if e != 0 {
+		err = errnoErr(e)
+	}
+	return
+}
+
+func Statfs(path string, buf *Statfs_t) (err error) {
+	p, err := BytePtrFromString(path)
+	if err != nil {
+		return err
+	}
+	_, _, e := Syscall(SYS_STATFS64, uintptr(unsafe.Pointer(p)), unsafe.Sizeof(*buf), uintptr(unsafe.Pointer(buf)))
+	use(unsafe.Pointer(p))
+	if e != 0 {
+		err = errnoErr(e)
+	}
+	return
+}
+
+func Seek(fd int, offset int64, whence int) (off int64, err error) {
+	_, _, e := Syscall6(SYS__LLSEEK, uintptr(fd), uintptr(offset>>32), uintptr(offset), uintptr(unsafe.Pointer(&off)), uintptr(whence), 0)
+	if e != 0 {
+		err = errnoErr(e)
+	}
+	return
+}
+
+func setTimespec(sec, nsec int64) Timespec {
+	return Timespec{Sec: int32(sec), Nsec: int32(nsec)}
+}
+
+func setTimeval(sec, usec int64) Timeval {
+	return Timeval{Sec: int32(sec), Usec: int32(usec)}
+}
+
+//sysnb pipe2(p *[2]_C_int, flags int) (err error)
+
+func Pipe2(p []int, flags int) (err error) {
+	if len(p) != 2 {
+		return EINVAL
+	}
+	var pp [2]_C_int
+	err = pipe2(&pp, flags)
+	p[0] = int(pp[0])
+	p[1] = int(pp[1])
+	return
+}
+
+func Pipe(p []int) (err error) {
+	if len(p) != 2 {
+		return EINVAL
+	}
+	var pp [2]_C_int
+	err = pipe2(&pp, 0)
+	p[0] = int(pp[0])
+	p[1] = int(pp[1])
+	return
+}
+
+//sys	mmap2(addr uintptr, length uintptr, prot int, flags int, fd int, pageOffset uintptr) (xaddr uintptr, err error)
+
+func mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, err error) {
+	page := uintptr(offset / 4096)
+	if offset != int64(page)*4096 {
+		return 0, EINVAL
+	}
+	return mmap2(addr, length, prot, flags, fd, page)
+}
+
+const rlimInf32 = ^uint32(0)
+const rlimInf64 = ^uint64(0)
+
+type rlimit32 struct {
+	Cur uint32
+	Max uint32
+}
+
+//sysnb getrlimit(resource int, rlim *rlimit32) (err error) = SYS_GETRLIMIT
+
+func Getrlimit(resource int, rlim *Rlimit) (err error) {
+	err = prlimit(0, resource, nil, rlim)
+	if err != ENOSYS {
+		return err
+	}
+
+	rl := rlimit32{}
+	err = getrlimit(resource, &rl)
+	if err != nil {
+		return
+	}
+
+	if rl.Cur == rlimInf32 {
+		rlim.Cur = rlimInf64
+	} else {
+		rlim.Cur = uint64(rl.Cur)
+	}
+
+	if rl.Max == rlimInf32 {
+		rlim.Max = rlimInf64
+	} else {
+		rlim.Max = uint64(rl.Max)
+	}
+	return
+}
+
+//sysnb setrlimit(resource int, rlim *rlimit32) (err error) = SYS_SETRLIMIT
+
+func Setrlimit(resource int, rlim *Rlimit) (err error) {
+	err = prlimit(0, resource, rlim, nil)
+	if err != ENOSYS {
+		return err
+	}
+
+	rl := rlimit32{}
+	if rlim.Cur == rlimInf64 {
+		rl.Cur = rlimInf32
+	} else if rlim.Cur < uint64(rlimInf32) {
+		rl.Cur = uint32(rlim.Cur)
+	} else {
+		return EINVAL
+	}
+	if rlim.Max == rlimInf64 {
+		rl.Max = rlimInf32
+	} else if rlim.Max < uint64(rlimInf32) {
+		rl.Max = uint32(rlim.Max)
+	} else {
+		return EINVAL
+	}
+
+	return setrlimit(resource, &rl)
+}
+
+func (r *PtraceRegs) PC() uint64 { return uint64(r.Regs[64]) }
+
+func (r *PtraceRegs) SetPC(pc uint64) { r.Regs[64] = uint32(pc) }
+
+func (iov *Iovec) SetLen(length int) {
+	iov.Len = uint32(length)
+}
+
+func (msghdr *Msghdr) SetControllen(length int) {
+	msghdr.Controllen = uint32(length)
+}
+
+func (cmsg *Cmsghdr) SetLen(length int) {
+	cmsg.Len = uint32(length)
+}

src/syscall/types_linux.go

@@ -112,7 +112,7 @@ typedef struct {} ptracePer;
 // The real epoll_event is a union, and godefs doesn't handle it well.
 struct my_epoll_event {
 	uint32_t events;
-#ifdef __ARM_EABI__
+#if defined(__ARM_EABI__) || (defined(__mips__) && _MIPS_SIM == _ABIO32)
 	// padding is not specified in linux/eventpoll.h but added to conform to the
 	// alignment requirements of EABI
 	int32_t padFd;