1// Copyright 2010 The Go Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style 3// license that can be found in the LICENSE file. 4 5// +build dragonfly freebsd netbsd openbsd solaris 6 7package runtime 8 9import ( 10 "unsafe" 11) 12 13// Don't split the stack as this function may be invoked without a valid G, 14// which prevents us from allocating more stack. 15//go:nosplit 16func sysAlloc(n uintptr, sysStat *uint64) unsafe.Pointer { 17 v, err := mmap(nil, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_PRIVATE, -1, 0) 18 if err != 0 { 19 return nil 20 } 21 mSysStatInc(sysStat, n) 22 return v 23} 24 25func sysUnused(v unsafe.Pointer, n uintptr) { 26 madvise(v, n, _MADV_FREE) 27} 28 29func sysUsed(v unsafe.Pointer, n uintptr) { 30} 31 32func sysHugePage(v unsafe.Pointer, n uintptr) { 33} 34 35// Don't split the stack as this function may be invoked without a valid G, 36// which prevents us from allocating more stack. 37//go:nosplit 38func sysFree(v unsafe.Pointer, n uintptr, sysStat *uint64) { 39 mSysStatDec(sysStat, n) 40 munmap(v, n) 41} 42 43func sysFault(v unsafe.Pointer, n uintptr) { 44 mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE|_MAP_FIXED, -1, 0) 45} 46 47// Indicates not to reserve swap space for the mapping. 48const _sunosMAP_NORESERVE = 0x40 49 50func sysReserve(v unsafe.Pointer, n uintptr) unsafe.Pointer { 51 flags := int32(_MAP_ANON | _MAP_PRIVATE) 52 if GOOS == "solaris" || GOOS == "illumos" { 53 // Be explicit that we don't want to reserve swap space 54 // for PROT_NONE anonymous mappings. This avoids an issue 55 // wherein large mappings can cause fork to fail. 56 flags |= _sunosMAP_NORESERVE 57 } 58 p, err := mmap(v, n, _PROT_NONE, flags, -1, 0) 59 if err != 0 { 60 return nil 61 } 62 return p 63} 64 65const _sunosEAGAIN = 11 66const _ENOMEM = 12 67 68func sysMap(v unsafe.Pointer, n uintptr, sysStat *uint64) { 69 mSysStatInc(sysStat, n) 70 71 p, err := mmap(v, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_FIXED|_MAP_PRIVATE, -1, 0) 72 if err == _ENOMEM || ((GOOS == "solaris" || GOOS == "illumos") && err == _sunosEAGAIN) { 73 throw("runtime: out of memory") 74 } 75 if p != v || err != 0 { 76 throw("runtime: cannot map pages in arena address space") 77 } 78} 79