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// Copyright 2010 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 dragonfly freebsd netbsd openbsd solaris
package runtime
import (
"unsafe"
)
// Don't split the stack as this function may be invoked without a valid G,
// which prevents us from allocating more stack.
//go:nosplit
func sysAlloc(n uintptr, sysStat *sysMemStat) unsafe.Pointer {
v, err := mmap(nil, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
if err != 0 {
return nil
}
sysStat.add(int64(n))
return v
}
func sysUnused(v unsafe.Pointer, n uintptr) {
madvise(v, n, _MADV_FREE)
}
func sysUsed(v unsafe.Pointer, n uintptr) {
}
func sysHugePage(v unsafe.Pointer, n uintptr) {
}
// Don't split the stack as this function may be invoked without a valid G,
// which prevents us from allocating more stack.
//go:nosplit
func sysFree(v unsafe.Pointer, n uintptr, sysStat *sysMemStat) {
sysStat.add(-int64(n))
munmap(v, n)
}
func sysFault(v unsafe.Pointer, n uintptr) {
mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE|_MAP_FIXED, -1, 0)
}
// Indicates not to reserve swap space for the mapping.
const _sunosMAP_NORESERVE = 0x40
func sysReserve(v unsafe.Pointer, n uintptr) unsafe.Pointer {
flags := int32(_MAP_ANON | _MAP_PRIVATE)
if GOOS == "solaris" || GOOS == "illumos" {
// Be explicit that we don't want to reserve swap space
// for PROT_NONE anonymous mappings. This avoids an issue
// wherein large mappings can cause fork to fail.
flags |= _sunosMAP_NORESERVE
}
p, err := mmap(v, n, _PROT_NONE, flags, -1, 0)
if err != 0 {
return nil
}
return p
}
const _sunosEAGAIN = 11
const _ENOMEM = 12
func sysMap(v unsafe.Pointer, n uintptr, sysStat *sysMemStat) {
sysStat.add(int64(n))
p, err := mmap(v, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_FIXED|_MAP_PRIVATE, -1, 0)
if err == _ENOMEM || ((GOOS == "solaris" || GOOS == "illumos") && err == _sunosEAGAIN) {
throw("runtime: out of memory")
}
if p != v || err != 0 {
throw("runtime: cannot map pages in arena address space")
}
}