Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 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 | |
| 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 | |
| 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* t = localtime(&tv); // NOLINT(runtime/threadsafe_fn) |
| 50 | if (NULL == t) return ""; |
| 51 | return tzname[0]; // The location of the timezone string on AIX. |
| 52 | } |
| 53 | |
| 54 | |
| 55 | double OS::LocalTimeOffset(TimezoneCache* cache) { |
| 56 | // On AIX, struct tm does not contain a tm_gmtoff field. |
| 57 | time_t utc = time(NULL); |
| 58 | DCHECK(utc != -1); |
| 59 | struct tm* loc = localtime(&utc); // NOLINT(runtime/threadsafe_fn) |
| 60 | DCHECK(loc != NULL); |
| 61 | return static_cast<double>((mktime(loc) - utc) * msPerSecond); |
| 62 | } |
| 63 | |
| 64 | |
| 65 | void* OS::Allocate(const size_t requested, size_t* allocated, bool executable) { |
| 66 | const size_t msize = RoundUp(requested, getpagesize()); |
| 67 | int prot = PROT_READ | PROT_WRITE | (executable ? PROT_EXEC : 0); |
| 68 | void* mbase = mmapHelper(msize, prot, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); |
| 69 | |
| 70 | if (mbase == MAP_FAILED) return NULL; |
| 71 | *allocated = msize; |
| 72 | return mbase; |
| 73 | } |
| 74 | |
| 75 | |
| 76 | static unsigned StringToLong(char* buffer) { |
| 77 | return static_cast<unsigned>(strtol(buffer, NULL, 16)); // NOLINT |
| 78 | } |
| 79 | |
| 80 | |
| 81 | std::vector<OS::SharedLibraryAddress> OS::GetSharedLibraryAddresses() { |
| 82 | std::vector<SharedLibraryAddress> result; |
| 83 | static const int MAP_LENGTH = 1024; |
| 84 | int fd = open("/proc/self/maps", O_RDONLY); |
| 85 | if (fd < 0) return result; |
| 86 | while (true) { |
| 87 | char addr_buffer[11]; |
| 88 | addr_buffer[0] = '0'; |
| 89 | addr_buffer[1] = 'x'; |
| 90 | addr_buffer[10] = 0; |
| 91 | ssize_t rc = read(fd, addr_buffer + 2, 8); |
| 92 | if (rc < 8) break; |
| 93 | unsigned start = StringToLong(addr_buffer); |
| 94 | rc = read(fd, addr_buffer + 2, 1); |
| 95 | if (rc < 1) break; |
| 96 | if (addr_buffer[2] != '-') break; |
| 97 | rc = read(fd, addr_buffer + 2, 8); |
| 98 | if (rc < 8) break; |
| 99 | unsigned end = StringToLong(addr_buffer); |
| 100 | char buffer[MAP_LENGTH]; |
| 101 | int bytes_read = -1; |
| 102 | do { |
| 103 | bytes_read++; |
| 104 | if (bytes_read >= MAP_LENGTH - 1) break; |
| 105 | rc = read(fd, buffer + bytes_read, 1); |
| 106 | if (rc < 1) break; |
| 107 | } while (buffer[bytes_read] != '\n'); |
| 108 | buffer[bytes_read] = 0; |
| 109 | // Ignore mappings that are not executable. |
| 110 | if (buffer[3] != 'x') continue; |
| 111 | char* start_of_path = index(buffer, '/'); |
| 112 | // There may be no filename in this line. Skip to next. |
| 113 | if (start_of_path == NULL) continue; |
| 114 | buffer[bytes_read] = 0; |
| 115 | result.push_back(SharedLibraryAddress(start_of_path, start, end)); |
| 116 | } |
| 117 | close(fd); |
| 118 | return result; |
| 119 | } |
| 120 | |
| 121 | |
| 122 | void OS::SignalCodeMovingGC() {} |
| 123 | |
| 124 | |
| 125 | // Constants used for mmap. |
| 126 | static const int kMmapFd = -1; |
| 127 | static const int kMmapFdOffset = 0; |
| 128 | |
| 129 | VirtualMemory::VirtualMemory() : address_(NULL), size_(0) {} |
| 130 | |
| 131 | |
| 132 | VirtualMemory::VirtualMemory(size_t size) |
| 133 | : address_(ReserveRegion(size)), size_(size) {} |
| 134 | |
| 135 | |
| 136 | VirtualMemory::VirtualMemory(size_t size, size_t alignment) |
| 137 | : address_(NULL), size_(0) { |
| 138 | DCHECK((alignment % OS::AllocateAlignment()) == 0); |
| 139 | size_t request_size = |
| 140 | RoundUp(size + alignment, static_cast<intptr_t>(OS::AllocateAlignment())); |
| 141 | void* reservation = |
| 142 | mmapHelper(request_size, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, kMmapFd, |
| 143 | kMmapFdOffset); |
| 144 | if (reservation == MAP_FAILED) return; |
| 145 | |
| 146 | uint8_t* base = static_cast<uint8_t*>(reservation); |
| 147 | uint8_t* aligned_base = RoundUp(base, alignment); |
| 148 | DCHECK_LE(base, aligned_base); |
| 149 | |
| 150 | // Unmap extra memory reserved before and after the desired block. |
| 151 | if (aligned_base != base) { |
| 152 | size_t prefix_size = static_cast<size_t>(aligned_base - base); |
| 153 | OS::Free(base, prefix_size); |
| 154 | request_size -= prefix_size; |
| 155 | } |
| 156 | |
| 157 | size_t aligned_size = RoundUp(size, OS::AllocateAlignment()); |
| 158 | DCHECK_LE(aligned_size, request_size); |
| 159 | |
| 160 | if (aligned_size != request_size) { |
| 161 | size_t suffix_size = request_size - aligned_size; |
| 162 | OS::Free(aligned_base + aligned_size, suffix_size); |
| 163 | request_size -= suffix_size; |
| 164 | } |
| 165 | |
| 166 | DCHECK(aligned_size == request_size); |
| 167 | |
| 168 | address_ = static_cast<void*>(aligned_base); |
| 169 | size_ = aligned_size; |
| 170 | } |
| 171 | |
| 172 | |
| 173 | VirtualMemory::~VirtualMemory() { |
| 174 | if (IsReserved()) { |
| 175 | bool result = ReleaseRegion(address(), size()); |
| 176 | DCHECK(result); |
| 177 | USE(result); |
| 178 | } |
| 179 | } |
| 180 | |
| 181 | |
| 182 | bool VirtualMemory::IsReserved() { return address_ != NULL; } |
| 183 | |
| 184 | |
| 185 | void VirtualMemory::Reset() { |
| 186 | address_ = NULL; |
| 187 | size_ = 0; |
| 188 | } |
| 189 | |
| 190 | |
| 191 | bool VirtualMemory::Commit(void* address, size_t size, bool is_executable) { |
| 192 | return CommitRegion(address, size, is_executable); |
| 193 | } |
| 194 | |
| 195 | |
| 196 | bool VirtualMemory::Uncommit(void* address, size_t size) { |
| 197 | return UncommitRegion(address, size); |
| 198 | } |
| 199 | |
| 200 | |
| 201 | bool VirtualMemory::Guard(void* address) { |
| 202 | OS::Guard(address, OS::CommitPageSize()); |
| 203 | return true; |
| 204 | } |
| 205 | |
| 206 | |
| 207 | void* VirtualMemory::ReserveRegion(size_t size) { |
| 208 | void* result = mmapHelper(size, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, |
| 209 | kMmapFd, kMmapFdOffset); |
| 210 | |
| 211 | if (result == MAP_FAILED) return NULL; |
| 212 | |
| 213 | return result; |
| 214 | } |
| 215 | |
| 216 | |
| 217 | bool VirtualMemory::CommitRegion(void* base, size_t size, bool is_executable) { |
| 218 | #if defined(__native_client__) |
| 219 | // The Native Client port of V8 uses an interpreter, |
| 220 | // so code pages don't need PROT_EXEC. |
| 221 | int prot = PROT_READ | PROT_WRITE; |
| 222 | #else |
| 223 | int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0); |
| 224 | #endif |
| 225 | if (mprotect(base, size, prot) == -1) return false; |
| 226 | |
| 227 | return true; |
| 228 | } |
| 229 | |
| 230 | |
| 231 | bool VirtualMemory::UncommitRegion(void* base, size_t size) { |
| 232 | return mprotect(base, size, PROT_NONE) != -1; |
| 233 | } |
| 234 | |
| 235 | |
| 236 | bool VirtualMemory::ReleaseRegion(void* base, size_t size) { |
| 237 | return munmap(base, size) == 0; |
| 238 | } |
| 239 | |
| 240 | |
| 241 | bool VirtualMemory::HasLazyCommits() { return true; } |
| 242 | } // namespace base |
| 243 | } // namespace v8 |