unix: add SysctlUvmexp on OpenBSD

OpenBSD uses sysctl with struct uvmexp to get information from the
virtual memory system of the kernel. Add type Uvmexp and the
SysctlUvmexp function to query this information.

This will be used in github.com/tklauser/go-sysconf to get
_SC_AVPHYS_PAGES on OpenBSD.

Change-Id: I96ded2d1be37e5307bab55e79b13234cc93d21e6
Reviewed-on: https://go-review.googlesource.com/c/139278
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

unix/syscall_openbsd.go

@@ -43,6 +43,23 @@ func nametomib(name string) (mib []_C_int, err error) {
 	return nil, EINVAL
 }
 
+func SysctlUvmexp(name string) (*Uvmexp, error) {
+	mib, err := sysctlmib(name)
+	if err != nil {
+		return nil, err
+	}
+
+	n := uintptr(SizeofUvmexp)
+	var u Uvmexp
+	if err := sysctl(mib, (*byte)(unsafe.Pointer(&u)), &n, nil, 0); err != nil {
+		return nil, err
+	}
+	if n != SizeofUvmexp {
+		return nil, EIO
+	}
+	return &u, nil
+}
+
 //sysnb pipe(p *[2]_C_int) (err error)
 func Pipe(p []int) (err error) {
 	if len(p) != 2 {

unix/syscall_openbsd_test.go

@@ -0,0 +1,19 @@
+// Copyright 2018 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.
+
+package unix_test
+
+import (
+	"testing"
+
+	"golang.org/x/sys/unix"
+)
+
+func TestSysctlUvmexp(t *testing.T) {
+	uvm, err := unix.SysctlUvmexp("vm.uvmexp")
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Logf("free = %v", uvm.Free)
+}

unix/types_openbsd.go

@@ -38,6 +38,7 @@ package unix
 #include <sys/un.h>
 #include <sys/utsname.h>
 #include <sys/wait.h>
+#include <uvm/uvmexp.h>
 #include <net/bpf.h>
 #include <net/if.h>
 #include <net/if_dl.h>
@@ -263,3 +264,9 @@ const (
 // Uname
 
 type Utsname C.struct_utsname
+
+// Uvmexp
+
+const SizeofUvmexp = C.sizeof_struct_uvmexp
+
+type Uvmexp C.struct_uvmexp

unix/zerrors_openbsd_amd64.go

@@ -952,6 +952,7 @@ const (
 	MNT_NOATIME                       = 0x8000
 	MNT_NODEV                         = 0x10
 	MNT_NOEXEC                        = 0x4
+	MNT_NOPERM                        = 0x20
 	MNT_NOSUID                        = 0x8
 	MNT_NOWAIT                        = 0x2
 	MNT_QUOTA                         = 0x2000
@@ -959,6 +960,7 @@ const (
 	MNT_RELOAD                        = 0x40000
 	MNT_ROOTFS                        = 0x4000
 	MNT_SOFTDEP                       = 0x4000000
+	MNT_STALLED                       = 0x100000
 	MNT_SYNCHRONOUS                   = 0x2
 	MNT_UPDATE                        = 0x10000
 	MNT_VISFLAGMASK                   = 0x400ffff
@@ -1441,6 +1443,8 @@ const (
 	TIOCUCNTL_CBRK                    = 0x7a
 	TIOCUCNTL_SBRK                    = 0x7b
 	TOSTOP                            = 0x400000
+	UTIME_NOW                         = -0x2
+	UTIME_OMIT                        = -0x1
 	VDISCARD                          = 0xf
 	VDSUSP                            = 0xb
 	VEOF                              = 0x0

unix/ztypes_openbsd_386.go

@@ -465,3 +465,94 @@ type Utsname struct {
 	Version  [256]byte
 	Machine  [256]byte
 }
+
+const SizeofUvmexp = 0x158
+
+type Uvmexp struct {
+	Pagesize           int32
+	Pagemask           int32
+	Pageshift          int32
+	Npages             int32
+	Free               int32
+	Active             int32
+	Inactive           int32
+	Paging             int32
+	Wired              int32
+	Zeropages          int32
+	Reserve_pagedaemon int32
+	Reserve_kernel     int32
+	Anonpages          int32
+	Vnodepages         int32
+	Vtextpages         int32
+	Freemin            int32
+	Freetarg           int32
+	Inactarg           int32
+	Wiredmax           int32
+	Anonmin            int32
+	Vtextmin           int32
+	Vnodemin           int32
+	Anonminpct         int32
+	Vtextminpct        int32
+	Vnodeminpct        int32
+	Nswapdev           int32
+	Swpages            int32
+	Swpginuse          int32
+	Swpgonly           int32
+	Nswget             int32
+	Nanon              int32
+	Nanonneeded        int32
+	Nfreeanon          int32
+	Faults             int32
+	Traps              int32
+	Intrs              int32
+	Swtch              int32
+	Softs              int32
+	Syscalls           int32
+	Pageins            int32
+	Obsolete_swapins   int32
+	Obsolete_swapouts  int32
+	Pgswapin           int32
+	Pgswapout          int32
+	Forks              int32
+	Forks_ppwait       int32
+	Forks_sharevm      int32
+	Pga_zerohit        int32
+	Pga_zeromiss       int32
+	Zeroaborts         int32
+	Fltnoram           int32
+	Fltnoanon          int32
+	Fltnoamap          int32
+	Fltpgwait          int32
+	Fltpgrele          int32
+	Fltrelck           int32
+	Fltrelckok         int32
+	Fltanget           int32
+	Fltanretry         int32
+	Fltamcopy          int32
+	Fltnamap           int32
+	Fltnomap           int32
+	Fltlget            int32
+	Fltget             int32
+	Flt_anon           int32
+	Flt_acow           int32
+	Flt_obj            int32
+	Flt_prcopy         int32
+	Flt_przero         int32
+	Pdwoke             int32
+	Pdrevs             int32
+	Pdswout            int32
+	Pdfreed            int32
+	Pdscans            int32
+	Pdanscan           int32
+	Pdobscan           int32
+	Pdreact            int32
+	Pdbusy             int32
+	Pdpageouts         int32
+	Pdpending          int32
+	Pddeact            int32
+	Pdreanon           int32
+	Pdrevnode          int32
+	Pdrevtext          int32
+	Fpswtch            int32
+	Kmapent            int32
+}

unix/ztypes_openbsd_amd64.go

@@ -465,3 +465,94 @@ type Utsname struct {
 	Version  [256]byte
 	Machine  [256]byte
 }
+
+const SizeofUvmexp = 0x158
+
+type Uvmexp struct {
+	Pagesize           int32
+	Pagemask           int32
+	Pageshift          int32
+	Npages             int32
+	Free               int32
+	Active             int32
+	Inactive           int32
+	Paging             int32
+	Wired              int32
+	Zeropages          int32
+	Reserve_pagedaemon int32
+	Reserve_kernel     int32
+	Anonpages          int32
+	Vnodepages         int32
+	Vtextpages         int32
+	Freemin            int32
+	Freetarg           int32
+	Inactarg           int32
+	Wiredmax           int32
+	Anonmin            int32
+	Vtextmin           int32
+	Vnodemin           int32
+	Anonminpct         int32
+	Vtextminpct        int32
+	Vnodeminpct        int32
+	Nswapdev           int32
+	Swpages            int32
+	Swpginuse          int32
+	Swpgonly           int32
+	Nswget             int32
+	Nanon              int32
+	Nanonneeded        int32
+	Nfreeanon          int32
+	Faults             int32
+	Traps              int32
+	Intrs              int32
+	Swtch              int32
+	Softs              int32
+	Syscalls           int32
+	Pageins            int32
+	Obsolete_swapins   int32
+	Obsolete_swapouts  int32
+	Pgswapin           int32
+	Pgswapout          int32
+	Forks              int32
+	Forks_ppwait       int32
+	Forks_sharevm      int32
+	Pga_zerohit        int32
+	Pga_zeromiss       int32
+	Zeroaborts         int32
+	Fltnoram           int32
+	Fltnoanon          int32
+	Fltnoamap          int32
+	Fltpgwait          int32
+	Fltpgrele          int32
+	Fltrelck           int32
+	Fltrelckok         int32
+	Fltanget           int32
+	Fltanretry         int32
+	Fltamcopy          int32
+	Fltnamap           int32
+	Fltnomap           int32
+	Fltlget            int32
+	Fltget             int32
+	Flt_anon           int32
+	Flt_acow           int32
+	Flt_obj            int32
+	Flt_prcopy         int32
+	Flt_przero         int32
+	Pdwoke             int32
+	Pdrevs             int32
+	Pdswout            int32
+	Pdfreed            int32
+	Pdscans            int32
+	Pdanscan           int32
+	Pdobscan           int32
+	Pdreact            int32
+	Pdbusy             int32
+	Pdpageouts         int32
+	Pdpending          int32
+	Pddeact            int32
+	Pdreanon           int32
+	Pdrevnode          int32
+	Pdrevtext          int32
+	Fpswtch            int32
+	Kmapent            int32
+}

unix/ztypes_openbsd_arm.go

@@ -458,3 +458,94 @@ type Utsname struct {
 	Version  [256]byte
 	Machine  [256]byte
 }
+
+const SizeofUvmexp = 0x158
+
+type Uvmexp struct {
+	Pagesize           int32
+	Pagemask           int32
+	Pageshift          int32
+	Npages             int32
+	Free               int32
+	Active             int32
+	Inactive           int32
+	Paging             int32
+	Wired              int32
+	Zeropages          int32
+	Reserve_pagedaemon int32
+	Reserve_kernel     int32
+	Anonpages          int32
+	Vnodepages         int32
+	Vtextpages         int32
+	Freemin            int32
+	Freetarg           int32
+	Inactarg           int32
+	Wiredmax           int32
+	Anonmin            int32
+	Vtextmin           int32
+	Vnodemin           int32
+	Anonminpct         int32
+	Vtextminpct        int32
+	Vnodeminpct        int32
+	Nswapdev           int32
+	Swpages            int32
+	Swpginuse          int32
+	Swpgonly           int32
+	Nswget             int32
+	Nanon              int32
+	Nanonneeded        int32
+	Nfreeanon          int32
+	Faults             int32
+	Traps              int32
+	Intrs              int32
+	Swtch              int32
+	Softs              int32
+	Syscalls           int32
+	Pageins            int32
+	Obsolete_swapins   int32
+	Obsolete_swapouts  int32
+	Pgswapin           int32
+	Pgswapout          int32
+	Forks              int32
+	Forks_ppwait       int32
+	Forks_sharevm      int32
+	Pga_zerohit        int32
+	Pga_zeromiss       int32
+	Zeroaborts         int32
+	Fltnoram           int32
+	Fltnoanon          int32
+	Fltnoamap          int32
+	Fltpgwait          int32
+	Fltpgrele          int32
+	Fltrelck           int32
+	Fltrelckok         int32
+	Fltanget           int32
+	Fltanretry         int32
+	Fltamcopy          int32
+	Fltnamap           int32
+	Fltnomap           int32
+	Fltlget            int32
+	Fltget             int32
+	Flt_anon           int32
+	Flt_acow           int32
+	Flt_obj            int32
+	Flt_prcopy         int32
+	Flt_przero         int32
+	Pdwoke             int32
+	Pdrevs             int32
+	Pdswout            int32
+	Pdfreed            int32
+	Pdscans            int32
+	Pdanscan           int32
+	Pdobscan           int32
+	Pdreact            int32
+	Pdbusy             int32
+	Pdpageouts         int32
+	Pdpending          int32
+	Pddeact            int32
+	Pdreanon           int32
+	Pdrevnode          int32
+	Pdrevtext          int32
+	Fpswtch            int32
+	Kmapent            int32
+}