Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2008 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #include "mem_map.h" |
| 18 | |
Christopher Ferris | 7b5f0cf | 2013-11-01 15:18:45 -0700 | [diff] [blame] | 19 | #include <backtrace/backtrace.h> |
Elliott Hughes | ecd3a6f | 2012-06-06 18:16:37 -0700 | [diff] [blame] | 20 | |
Elliott Hughes | e222ee0 | 2012-12-13 14:41:43 -0800 | [diff] [blame] | 21 | #include "base/stringprintf.h" |
| 22 | #include "ScopedFd.h" |
| 23 | #include "utils.h" |
| 24 | |
Elliott Hughes | 6c9c06d | 2011-11-07 16:43:47 -0800 | [diff] [blame] | 25 | #define USE_ASHMEM 1 |
| 26 | |
| 27 | #ifdef USE_ASHMEM |
| 28 | #include <cutils/ashmem.h> |
| 29 | #endif |
| 30 | |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 31 | namespace art { |
| 32 | |
Elliott Hughes | 96970cd | 2012-03-13 15:46:31 -0700 | [diff] [blame] | 33 | #if !defined(NDEBUG) |
| 34 | |
Christopher Ferris | 7b5f0cf | 2013-11-01 15:18:45 -0700 | [diff] [blame] | 35 | static std::ostream& operator<<(std::ostream& os, backtrace_map_info_t* rhs) { |
| 36 | for (backtrace_map_info_t* m = rhs; m != NULL; m = m->next) { |
Elliott Hughes | 7bda158 | 2012-06-07 11:00:54 -0700 | [diff] [blame] | 37 | os << StringPrintf("0x%08x-0x%08x %c%c %s\n", |
| 38 | static_cast<uint32_t>(m->start), |
| 39 | static_cast<uint32_t>(m->end), |
Elliott Hughes | ecd3a6f | 2012-06-06 18:16:37 -0700 | [diff] [blame] | 40 | m->is_readable ? 'r' : '-', m->is_executable ? 'x' : '-', m->name); |
| 41 | } |
| 42 | return os; |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 43 | } |
| 44 | |
Ian Rogers | 10c5b78 | 2013-01-10 10:40:53 -0800 | [diff] [blame] | 45 | static void CheckMapRequest(byte* addr, size_t byte_count) { |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 46 | if (addr == NULL) { |
| 47 | return; |
| 48 | } |
Elliott Hughes | ecd3a6f | 2012-06-06 18:16:37 -0700 | [diff] [blame] | 49 | |
Elliott Hughes | 96970cd | 2012-03-13 15:46:31 -0700 | [diff] [blame] | 50 | uint32_t base = reinterpret_cast<size_t>(addr); |
Elliott Hughes | ecd3a6f | 2012-06-06 18:16:37 -0700 | [diff] [blame] | 51 | uint32_t limit = base + byte_count; |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 52 | |
Christopher Ferris | 7b5f0cf | 2013-11-01 15:18:45 -0700 | [diff] [blame] | 53 | backtrace_map_info_t* map_info_list = backtrace_create_map_info_list(getpid()); |
| 54 | for (backtrace_map_info_t* m = map_info_list; m != NULL; m = m->next) { |
Brian Carlstrom | 7934ac2 | 2013-07-26 10:54:15 -0700 | [diff] [blame] | 55 | CHECK(!(base >= m->start && base < m->end) // start of new within old |
| 56 | && !(limit > m->start && limit < m->end) // end of new within old |
| 57 | && !(base <= m->start && limit > m->end)) // start/end of new includes all of old |
Elliott Hughes | 7bda158 | 2012-06-07 11:00:54 -0700 | [diff] [blame] | 58 | << StringPrintf("Requested region 0x%08x-0x%08x overlaps with existing map 0x%08x-0x%08x (%s)\n", |
| 59 | base, limit, |
| 60 | static_cast<uint32_t>(m->start), static_cast<uint32_t>(m->end), m->name) |
Elliott Hughes | ecd3a6f | 2012-06-06 18:16:37 -0700 | [diff] [blame] | 61 | << map_info_list; |
Elliott Hughes | 96970cd | 2012-03-13 15:46:31 -0700 | [diff] [blame] | 62 | } |
Christopher Ferris | 7b5f0cf | 2013-11-01 15:18:45 -0700 | [diff] [blame] | 63 | backtrace_destroy_map_info_list(map_info_list); |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 64 | } |
| 65 | |
Elliott Hughes | 96970cd | 2012-03-13 15:46:31 -0700 | [diff] [blame] | 66 | #else |
Elliott Hughes | 1bac54f | 2012-03-16 12:48:31 -0700 | [diff] [blame] | 67 | static void CheckMapRequest(byte*, size_t) { } |
Elliott Hughes | 96970cd | 2012-03-13 15:46:31 -0700 | [diff] [blame] | 68 | #endif |
| 69 | |
Ian Rogers | 8d31bbd | 2013-10-13 10:44:14 -0700 | [diff] [blame] | 70 | MemMap* MemMap::MapAnonymous(const char* name, byte* addr, size_t byte_count, int prot, |
| 71 | std::string* error_msg) { |
Brian Carlstrom | 9004cb6 | 2013-07-26 15:48:31 -0700 | [diff] [blame] | 72 | if (byte_count == 0) { |
| 73 | return new MemMap(name, NULL, 0, NULL, 0, prot); |
| 74 | } |
Elliott Hughes | ecd3a6f | 2012-06-06 18:16:37 -0700 | [diff] [blame] | 75 | size_t page_aligned_byte_count = RoundUp(byte_count, kPageSize); |
| 76 | CheckMapRequest(addr, page_aligned_byte_count); |
Elliott Hughes | 6c9c06d | 2011-11-07 16:43:47 -0800 | [diff] [blame] | 77 | |
| 78 | #ifdef USE_ASHMEM |
Ian Rogers | a40307e | 2013-02-22 11:32:44 -0800 | [diff] [blame] | 79 | // android_os_Debug.cpp read_mapinfo assumes all ashmem regions associated with the VM are |
| 80 | // prefixed "dalvik-". |
| 81 | std::string debug_friendly_name("dalvik-"); |
| 82 | debug_friendly_name += name; |
| 83 | ScopedFd fd(ashmem_create_region(debug_friendly_name.c_str(), page_aligned_byte_count)); |
Elliott Hughes | 6c9c06d | 2011-11-07 16:43:47 -0800 | [diff] [blame] | 84 | int flags = MAP_PRIVATE; |
| 85 | if (fd.get() == -1) { |
Ian Rogers | 8d31bbd | 2013-10-13 10:44:14 -0700 | [diff] [blame] | 86 | *error_msg = StringPrintf("ashmem_create_region failed for '%s': %s", name, strerror(errno)); |
| 87 | return nullptr; |
Elliott Hughes | 6c9c06d | 2011-11-07 16:43:47 -0800 | [diff] [blame] | 88 | } |
| 89 | #else |
| 90 | ScopedFd fd(-1); |
| 91 | int flags = MAP_PRIVATE | MAP_ANONYMOUS; |
| 92 | #endif |
| 93 | |
Elliott Hughes | ecd3a6f | 2012-06-06 18:16:37 -0700 | [diff] [blame] | 94 | byte* actual = reinterpret_cast<byte*>(mmap(addr, page_aligned_byte_count, prot, flags, fd.get(), 0)); |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 95 | if (actual == MAP_FAILED) { |
jeffhao | 8161c03 | 2012-10-31 15:50:00 -0700 | [diff] [blame] | 96 | std::string maps; |
| 97 | ReadFileToString("/proc/self/maps", &maps); |
Ian Rogers | 8d31bbd | 2013-10-13 10:44:14 -0700 | [diff] [blame] | 98 | *error_msg = StringPrintf("anonymous mmap(%p, %zd, %x, %x, %d, 0) failed\n%s", |
| 99 | addr, page_aligned_byte_count, prot, flags, fd.get(), |
| 100 | maps.c_str()); |
| 101 | return nullptr; |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 102 | } |
Mathieu Chartier | 1c23e1e | 2012-10-12 14:14:11 -0700 | [diff] [blame] | 103 | return new MemMap(name, actual, byte_count, actual, page_aligned_byte_count, prot); |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 104 | } |
| 105 | |
Ian Rogers | 8d31bbd | 2013-10-13 10:44:14 -0700 | [diff] [blame] | 106 | MemMap* MemMap::MapFileAtAddress(byte* addr, size_t byte_count, int prot, int flags, int fd, |
| 107 | off_t start, bool reuse, const char* filename, |
| 108 | std::string* error_msg) { |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 109 | CHECK_NE(0, prot); |
| 110 | CHECK_NE(0, flags & (MAP_SHARED | MAP_PRIVATE)); |
Brian Carlstrom | 9004cb6 | 2013-07-26 15:48:31 -0700 | [diff] [blame] | 111 | if (byte_count == 0) { |
| 112 | return new MemMap("file", NULL, 0, NULL, 0, prot); |
| 113 | } |
Ian Rogers | f8adc60 | 2013-04-18 17:06:19 -0700 | [diff] [blame] | 114 | // Adjust 'offset' to be page-aligned as required by mmap. |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 115 | int page_offset = start % kPageSize; |
| 116 | off_t page_aligned_offset = start - page_offset; |
Ian Rogers | f8adc60 | 2013-04-18 17:06:19 -0700 | [diff] [blame] | 117 | // Adjust 'byte_count' to be page-aligned as we will map this anyway. |
Elliott Hughes | ecd3a6f | 2012-06-06 18:16:37 -0700 | [diff] [blame] | 118 | size_t page_aligned_byte_count = RoundUp(byte_count + page_offset, kPageSize); |
Ian Rogers | f8adc60 | 2013-04-18 17:06:19 -0700 | [diff] [blame] | 119 | // The 'addr' is modified (if specified, ie non-null) to be page aligned to the file but not |
| 120 | // necessarily to virtual memory. mmap will page align 'addr' for us. |
| 121 | byte* page_aligned_addr = (addr == NULL) ? NULL : (addr - page_offset); |
Brian Carlstrom | 700c8d3 | 2012-11-05 10:42:02 -0800 | [diff] [blame] | 122 | if (!reuse) { |
| 123 | // reuse means it is okay that it overlaps an existing page mapping. |
| 124 | // Only use this if you actually made the page reservation yourself. |
| 125 | CheckMapRequest(page_aligned_addr, page_aligned_byte_count); |
Ian Rogers | f8adc60 | 2013-04-18 17:06:19 -0700 | [diff] [blame] | 126 | } else { |
| 127 | CHECK(addr != NULL); |
Brian Carlstrom | 700c8d3 | 2012-11-05 10:42:02 -0800 | [diff] [blame] | 128 | } |
| 129 | byte* actual = reinterpret_cast<byte*>(mmap(page_aligned_addr, |
Elliott Hughes | ecd3a6f | 2012-06-06 18:16:37 -0700 | [diff] [blame] | 130 | page_aligned_byte_count, |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 131 | prot, |
| 132 | flags, |
| 133 | fd, |
| 134 | page_aligned_offset)); |
| 135 | if (actual == MAP_FAILED) { |
Mathieu Chartier | 3b6f0fa | 2013-11-13 13:26:07 -0800 | [diff] [blame] | 136 | std::string strerr(strerror(errno)); |
jeffhao | 8161c03 | 2012-10-31 15:50:00 -0700 | [diff] [blame] | 137 | std::string maps; |
| 138 | ReadFileToString("/proc/self/maps", &maps); |
Mathieu Chartier | 3b6f0fa | 2013-11-13 13:26:07 -0800 | [diff] [blame] | 139 | *error_msg = StringPrintf("mmap(%p, %zd, %x, %x, %d, %lld) of file '%s' failed: %s\n%s", |
Ian Rogers | 8d31bbd | 2013-10-13 10:44:14 -0700 | [diff] [blame] | 140 | page_aligned_addr, page_aligned_byte_count, prot, flags, fd, |
Mathieu Chartier | 3b6f0fa | 2013-11-13 13:26:07 -0800 | [diff] [blame] | 141 | static_cast<int64_t>(page_aligned_offset), filename, strerr.c_str(), |
| 142 | maps.c_str()); |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 143 | return NULL; |
| 144 | } |
Mathieu Chartier | 1c23e1e | 2012-10-12 14:14:11 -0700 | [diff] [blame] | 145 | return new MemMap("file", actual + page_offset, byte_count, actual, page_aligned_byte_count, |
| 146 | prot); |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 147 | } |
| 148 | |
| 149 | MemMap::~MemMap() { |
Ian Rogers | 30fab40 | 2012-01-23 15:43:46 -0800 | [diff] [blame] | 150 | if (base_begin_ == NULL && base_size_ == 0) { |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 151 | return; |
| 152 | } |
Ian Rogers | 30fab40 | 2012-01-23 15:43:46 -0800 | [diff] [blame] | 153 | int result = munmap(base_begin_, base_size_); |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 154 | if (result == -1) { |
| 155 | PLOG(FATAL) << "munmap failed"; |
| 156 | } |
| 157 | } |
| 158 | |
Mathieu Chartier | 1c23e1e | 2012-10-12 14:14:11 -0700 | [diff] [blame] | 159 | MemMap::MemMap(const std::string& name, byte* begin, size_t size, void* base_begin, |
| 160 | size_t base_size, int prot) |
| 161 | : name_(name), begin_(begin), size_(size), base_begin_(base_begin), base_size_(base_size), |
| 162 | prot_(prot) { |
Brian Carlstrom | 9004cb6 | 2013-07-26 15:48:31 -0700 | [diff] [blame] | 163 | if (size_ == 0) { |
| 164 | CHECK(begin_ == NULL); |
| 165 | CHECK(base_begin_ == NULL); |
| 166 | CHECK_EQ(base_size_, 0U); |
| 167 | } else { |
| 168 | CHECK(begin_ != NULL); |
| 169 | CHECK(base_begin_ != NULL); |
| 170 | CHECK_NE(base_size_, 0U); |
| 171 | } |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 172 | }; |
| 173 | |
Hiroshi Yamauchi | fd7e7f1 | 2013-10-22 14:17:48 -0700 | [diff] [blame] | 174 | MemMap* MemMap::RemapAtEnd(byte* new_end, const char* tail_name, int tail_prot, |
| 175 | std::string* error_msg) { |
Mathieu Chartier | cc236d7 | 2012-07-20 10:29:05 -0700 | [diff] [blame] | 176 | DCHECK_GE(new_end, Begin()); |
| 177 | DCHECK_LE(new_end, End()); |
Hiroshi Yamauchi | fd7e7f1 | 2013-10-22 14:17:48 -0700 | [diff] [blame] | 178 | DCHECK_LE(begin_ + size_, reinterpret_cast<byte*>(base_begin_) + base_size_); |
| 179 | DCHECK(IsAligned<kPageSize>(begin_)); |
| 180 | DCHECK(IsAligned<kPageSize>(base_begin_)); |
| 181 | DCHECK(IsAligned<kPageSize>(reinterpret_cast<byte*>(base_begin_) + base_size_)); |
| 182 | DCHECK(IsAligned<kPageSize>(new_end)); |
| 183 | byte* old_end = begin_ + size_; |
| 184 | byte* old_base_end = reinterpret_cast<byte*>(base_begin_) + base_size_; |
| 185 | byte* new_base_end = new_end; |
| 186 | DCHECK_LE(new_base_end, old_base_end); |
| 187 | if (new_base_end == old_base_end) { |
| 188 | return new MemMap(tail_name, NULL, 0, NULL, 0, tail_prot); |
| 189 | } |
| 190 | size_ = new_end - reinterpret_cast<byte*>(begin_); |
| 191 | base_size_ = new_base_end - reinterpret_cast<byte*>(base_begin_); |
| 192 | DCHECK_LE(begin_ + size_, reinterpret_cast<byte*>(base_begin_) + base_size_); |
| 193 | size_t tail_size = old_end - new_end; |
| 194 | byte* tail_base_begin = new_base_end; |
| 195 | size_t tail_base_size = old_base_end - new_base_end; |
| 196 | DCHECK_EQ(tail_base_begin + tail_base_size, old_base_end); |
| 197 | DCHECK(IsAligned<kPageSize>(tail_base_size)); |
| 198 | |
| 199 | #ifdef USE_ASHMEM |
| 200 | // android_os_Debug.cpp read_mapinfo assumes all ashmem regions associated with the VM are |
| 201 | // prefixed "dalvik-". |
| 202 | std::string debug_friendly_name("dalvik-"); |
| 203 | debug_friendly_name += tail_name; |
| 204 | ScopedFd fd(ashmem_create_region(debug_friendly_name.c_str(), tail_base_size)); |
| 205 | int flags = MAP_PRIVATE; |
| 206 | if (fd.get() == -1) { |
| 207 | *error_msg = StringPrintf("ashmem_create_region failed for '%s': %s", |
| 208 | tail_name, strerror(errno)); |
| 209 | return nullptr; |
| 210 | } |
| 211 | #else |
| 212 | ScopedFd fd(-1); |
| 213 | int flags = MAP_PRIVATE | MAP_ANONYMOUS; |
| 214 | #endif |
| 215 | |
| 216 | // Unmap/map the tail region. |
| 217 | int result = munmap(tail_base_begin, tail_base_size); |
| 218 | if (result == -1) { |
| 219 | std::string maps; |
| 220 | ReadFileToString("/proc/self/maps", &maps); |
| 221 | *error_msg = StringPrintf("munmap(%p, %zd) failed for '%s'\n%s", |
| 222 | tail_base_begin, tail_base_size, name_.c_str(), |
| 223 | maps.c_str()); |
| 224 | return nullptr; |
| 225 | } |
| 226 | // Don't cause memory allocation between the munmap and the mmap |
| 227 | // calls. Otherwise, libc (or something else) might take this memory |
| 228 | // region. Note this isn't perfect as there's no way to prevent |
| 229 | // other threads to try to take this memory region here. |
| 230 | byte* actual = reinterpret_cast<byte*>(mmap(tail_base_begin, tail_base_size, tail_prot, |
| 231 | flags, fd.get(), 0)); |
| 232 | if (actual == MAP_FAILED) { |
| 233 | std::string maps; |
| 234 | ReadFileToString("/proc/self/maps", &maps); |
| 235 | *error_msg = StringPrintf("anonymous mmap(%p, %zd, %x, %x, %d, 0) failed\n%s", |
| 236 | tail_base_begin, tail_base_size, tail_prot, flags, fd.get(), |
| 237 | maps.c_str()); |
| 238 | return nullptr; |
| 239 | } |
| 240 | return new MemMap(tail_name, actual, tail_size, actual, tail_base_size, tail_prot); |
Mathieu Chartier | cc236d7 | 2012-07-20 10:29:05 -0700 | [diff] [blame] | 241 | } |
Logan Chien | d88fa26 | 2012-06-06 15:23:32 +0800 | [diff] [blame] | 242 | |
| 243 | bool MemMap::Protect(int prot) { |
| 244 | if (base_begin_ == NULL && base_size_ == 0) { |
Ian Rogers | 1c849e5 | 2012-06-28 14:00:33 -0700 | [diff] [blame] | 245 | prot_ = prot; |
Logan Chien | d88fa26 | 2012-06-06 15:23:32 +0800 | [diff] [blame] | 246 | return true; |
| 247 | } |
| 248 | |
| 249 | if (mprotect(base_begin_, base_size_, prot) == 0) { |
Ian Rogers | 1c849e5 | 2012-06-28 14:00:33 -0700 | [diff] [blame] | 250 | prot_ = prot; |
Logan Chien | d88fa26 | 2012-06-06 15:23:32 +0800 | [diff] [blame] | 251 | return true; |
| 252 | } |
| 253 | |
Shih-wei Liao | a060ed9 | 2012-06-07 09:25:28 -0700 | [diff] [blame] | 254 | PLOG(ERROR) << "mprotect(" << reinterpret_cast<void*>(base_begin_) << ", " << base_size_ << ", " |
| 255 | << prot << ") failed"; |
Logan Chien | d88fa26 | 2012-06-06 15:23:32 +0800 | [diff] [blame] | 256 | return false; |
| 257 | } |
| 258 | |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 259 | } // namespace art |