1 // Copyright 2014 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 // Platform specific code for AIX goes here. For the POSIX comaptible parts
6 // the implementation is in platform-posix.cc.
7
8 #include <pthread.h>
9 #include <semaphore.h>
10 #include <signal.h>
11 #include <stdio.h>
12 #include <stdlib.h>
13 #include <sys/resource.h>
14 #include <sys/time.h>
15 #include <sys/ucontext.h>
16
17 #include <errno.h>
18 #include <fcntl.h> // open
19 #include <limits.h>
20 #include <stdarg.h>
21 #include <strings.h> // index
22 #include <sys/mman.h> // mmap & munmap
23 #include <sys/stat.h> // open
24 #include <sys/types.h> // mmap & munmap
25 #include <unistd.h> // getpagesize
26
27 #include <cmath>
28
29 #undef MAP_TYPE
30
31 #include "src/base/macros.h"
32 #include "src/base/platform/platform.h"
33
34
35 namespace v8 {
36 namespace base {
37
38
mmapHelper(size_t len,int prot,int flags,int fildes,off_t off)39 static inline void* mmapHelper(size_t len, int prot, int flags, int fildes,
40 off_t off) {
41 void* addr = OS::GetRandomMmapAddr();
42 return mmap(addr, len, prot, flags, fildes, off);
43 }
44
45
LocalTimezone(double time,TimezoneCache * cache)46 const char* OS::LocalTimezone(double time, TimezoneCache* cache) {
47 if (std::isnan(time)) return "";
48 time_t tv = static_cast<time_t>(floor(time / msPerSecond));
49 struct tm tm;
50 struct tm* t = localtime_r(&tv, &tm);
51 if (NULL == t) return "";
52 return tzname[0]; // The location of the timezone string on AIX.
53 }
54
55
LocalTimeOffset(TimezoneCache * cache)56 double OS::LocalTimeOffset(TimezoneCache* cache) {
57 // On AIX, struct tm does not contain a tm_gmtoff field.
58 time_t utc = time(NULL);
59 DCHECK(utc != -1);
60 struct tm tm;
61 struct tm* loc = localtime_r(&utc, &tm);
62 DCHECK(loc != NULL);
63 return static_cast<double>((mktime(loc) - utc) * msPerSecond);
64 }
65
66
Allocate(const size_t requested,size_t * allocated,bool executable)67 void* OS::Allocate(const size_t requested, size_t* allocated, bool executable) {
68 const size_t msize = RoundUp(requested, getpagesize());
69 int prot = PROT_READ | PROT_WRITE | (executable ? PROT_EXEC : 0);
70 void* mbase = mmapHelper(msize, prot, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
71
72 if (mbase == MAP_FAILED) return NULL;
73 *allocated = msize;
74 return mbase;
75 }
76
77
StringToLong(char * buffer)78 static unsigned StringToLong(char* buffer) {
79 return static_cast<unsigned>(strtol(buffer, NULL, 16)); // NOLINT
80 }
81
82
GetSharedLibraryAddresses()83 std::vector<OS::SharedLibraryAddress> OS::GetSharedLibraryAddresses() {
84 std::vector<SharedLibraryAddress> result;
85 static const int MAP_LENGTH = 1024;
86 int fd = open("/proc/self/maps", O_RDONLY);
87 if (fd < 0) return result;
88 while (true) {
89 char addr_buffer[11];
90 addr_buffer[0] = '0';
91 addr_buffer[1] = 'x';
92 addr_buffer[10] = 0;
93 ssize_t rc = read(fd, addr_buffer + 2, 8);
94 if (rc < 8) break;
95 unsigned start = StringToLong(addr_buffer);
96 rc = read(fd, addr_buffer + 2, 1);
97 if (rc < 1) break;
98 if (addr_buffer[2] != '-') break;
99 rc = read(fd, addr_buffer + 2, 8);
100 if (rc < 8) break;
101 unsigned end = StringToLong(addr_buffer);
102 char buffer[MAP_LENGTH];
103 int bytes_read = -1;
104 do {
105 bytes_read++;
106 if (bytes_read >= MAP_LENGTH - 1) break;
107 rc = read(fd, buffer + bytes_read, 1);
108 if (rc < 1) break;
109 } while (buffer[bytes_read] != '\n');
110 buffer[bytes_read] = 0;
111 // Ignore mappings that are not executable.
112 if (buffer[3] != 'x') continue;
113 char* start_of_path = index(buffer, '/');
114 // There may be no filename in this line. Skip to next.
115 if (start_of_path == NULL) continue;
116 buffer[bytes_read] = 0;
117 result.push_back(SharedLibraryAddress(start_of_path, start, end));
118 }
119 close(fd);
120 return result;
121 }
122
123
SignalCodeMovingGC()124 void OS::SignalCodeMovingGC() {}
125
126
127 // Constants used for mmap.
128 static const int kMmapFd = -1;
129 static const int kMmapFdOffset = 0;
130
VirtualMemory()131 VirtualMemory::VirtualMemory() : address_(NULL), size_(0) {}
132
133
VirtualMemory(size_t size)134 VirtualMemory::VirtualMemory(size_t size)
135 : address_(ReserveRegion(size)), size_(size) {}
136
137
VirtualMemory(size_t size,size_t alignment)138 VirtualMemory::VirtualMemory(size_t size, size_t alignment)
139 : address_(NULL), size_(0) {
140 DCHECK((alignment % OS::AllocateAlignment()) == 0);
141 size_t request_size =
142 RoundUp(size + alignment, static_cast<intptr_t>(OS::AllocateAlignment()));
143 void* reservation =
144 mmapHelper(request_size, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, kMmapFd,
145 kMmapFdOffset);
146 if (reservation == MAP_FAILED) return;
147
148 uint8_t* base = static_cast<uint8_t*>(reservation);
149 uint8_t* aligned_base = RoundUp(base, alignment);
150 DCHECK_LE(base, aligned_base);
151
152 // Unmap extra memory reserved before and after the desired block.
153 if (aligned_base != base) {
154 size_t prefix_size = static_cast<size_t>(aligned_base - base);
155 OS::Free(base, prefix_size);
156 request_size -= prefix_size;
157 }
158
159 size_t aligned_size = RoundUp(size, OS::AllocateAlignment());
160 DCHECK_LE(aligned_size, request_size);
161
162 if (aligned_size != request_size) {
163 size_t suffix_size = request_size - aligned_size;
164 OS::Free(aligned_base + aligned_size, suffix_size);
165 request_size -= suffix_size;
166 }
167
168 DCHECK(aligned_size == request_size);
169
170 address_ = static_cast<void*>(aligned_base);
171 size_ = aligned_size;
172 }
173
174
~VirtualMemory()175 VirtualMemory::~VirtualMemory() {
176 if (IsReserved()) {
177 bool result = ReleaseRegion(address(), size());
178 DCHECK(result);
179 USE(result);
180 }
181 }
182
183
IsReserved()184 bool VirtualMemory::IsReserved() { return address_ != NULL; }
185
186
Reset()187 void VirtualMemory::Reset() {
188 address_ = NULL;
189 size_ = 0;
190 }
191
192
Commit(void * address,size_t size,bool is_executable)193 bool VirtualMemory::Commit(void* address, size_t size, bool is_executable) {
194 return CommitRegion(address, size, is_executable);
195 }
196
197
Uncommit(void * address,size_t size)198 bool VirtualMemory::Uncommit(void* address, size_t size) {
199 return UncommitRegion(address, size);
200 }
201
202
Guard(void * address)203 bool VirtualMemory::Guard(void* address) {
204 OS::Guard(address, OS::CommitPageSize());
205 return true;
206 }
207
208
ReserveRegion(size_t size)209 void* VirtualMemory::ReserveRegion(size_t size) {
210 void* result = mmapHelper(size, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS,
211 kMmapFd, kMmapFdOffset);
212
213 if (result == MAP_FAILED) return NULL;
214
215 return result;
216 }
217
218
CommitRegion(void * base,size_t size,bool is_executable)219 bool VirtualMemory::CommitRegion(void* base, size_t size, bool is_executable) {
220 int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0);
221
222 if (mprotect(base, size, prot) == -1) return false;
223
224 return true;
225 }
226
227
UncommitRegion(void * base,size_t size)228 bool VirtualMemory::UncommitRegion(void* base, size_t size) {
229 return mprotect(base, size, PROT_NONE) != -1;
230 }
231
ReleasePartialRegion(void * base,size_t size,void * free_start,size_t free_size)232 bool VirtualMemory::ReleasePartialRegion(void* base, size_t size,
233 void* free_start, size_t free_size) {
234 return munmap(free_start, free_size) == 0;
235 }
236
237
ReleaseRegion(void * base,size_t size)238 bool VirtualMemory::ReleaseRegion(void* base, size_t size) {
239 return munmap(base, size) == 0;
240 }
241
242
HasLazyCommits()243 bool VirtualMemory::HasLazyCommits() { return true; }
244 } // namespace base
245 } // namespace v8
246