Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -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 | |
Brian Carlstrom | fc0e321 | 2013-07-17 14:40:12 -0700 | [diff] [blame] | 17 | #ifndef ART_RUNTIME_MEM_MAP_H_ |
| 18 | #define ART_RUNTIME_MEM_MAP_H_ |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 19 | |
Hiroshi Yamauchi | 3eed93d | 2014-06-04 11:43:59 -0700 | [diff] [blame] | 20 | #include "base/mutex.h" |
| 21 | |
Mathieu Chartier | 1c23e1e | 2012-10-12 14:14:11 -0700 | [diff] [blame] | 22 | #include <string> |
Hiroshi Yamauchi | 3eed93d | 2014-06-04 11:43:59 -0700 | [diff] [blame] | 23 | #include <map> |
Mathieu Chartier | 1c23e1e | 2012-10-12 14:14:11 -0700 | [diff] [blame] | 24 | |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 25 | #include <stddef.h> |
Elliott Hughes | a168c83 | 2012-06-12 15:34:20 -0700 | [diff] [blame] | 26 | #include <sys/mman.h> // For the PROT_* and MAP_* constants. |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 27 | #include <sys/types.h> |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 28 | |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 29 | #include "globals.h" |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 30 | |
| 31 | namespace art { |
| 32 | |
Ian Rogers | c3ccc10 | 2014-06-25 11:52:14 -0700 | [diff] [blame] | 33 | #if defined(__LP64__) && (!defined(__x86_64__) || defined(__APPLE__)) |
| 34 | #define USE_ART_LOW_4G_ALLOCATOR 1 |
| 35 | #else |
| 36 | #define USE_ART_LOW_4G_ALLOCATOR 0 |
| 37 | #endif |
| 38 | |
Ian Rogers | c5f1773 | 2014-06-05 20:48:42 -0700 | [diff] [blame] | 39 | #ifdef __linux__ |
| 40 | static constexpr bool kMadviseZeroes = true; |
| 41 | #else |
| 42 | static constexpr bool kMadviseZeroes = false; |
| 43 | #endif |
| 44 | |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 45 | // Used to keep track of mmap segments. |
Andreas Gampe | d8f26db | 2014-05-19 17:01:13 -0700 | [diff] [blame] | 46 | // |
| 47 | // On 64b systems not supporting MAP_32BIT, the implementation of MemMap will do a linear scan |
| 48 | // for free pages. For security, the start of this scan should be randomized. This requires a |
| 49 | // dynamic initializer. |
| 50 | // For this to work, it is paramount that there are no other static initializers that access MemMap. |
| 51 | // Otherwise, calls might see uninitialized values. |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 52 | class MemMap { |
| 53 | public: |
Elliott Hughes | ecd3a6f | 2012-06-06 18:16:37 -0700 | [diff] [blame] | 54 | // Request an anonymous region of length 'byte_count' and a requested base address. |
Elliott Hughes | 6c9c06d | 2011-11-07 16:43:47 -0800 | [diff] [blame] | 55 | // Use NULL as the requested base address if you don't care. |
| 56 | // |
| 57 | // The word "anonymous" in this context means "not backed by a file". The supplied |
| 58 | // 'ashmem_name' will be used -- on systems that support it -- to give the mapping |
| 59 | // a name. |
Brian Carlstrom | 4a289ed | 2011-08-16 17:17:49 -0700 | [diff] [blame] | 60 | // |
| 61 | // On success, returns returns a MemMap instance. On failure, returns a NULL; |
Ian Rogers | 8d31bbd | 2013-10-13 10:44:14 -0700 | [diff] [blame] | 62 | static MemMap* MapAnonymous(const char* ashmem_name, byte* addr, size_t byte_count, int prot, |
Ian Rogers | ef7d42f | 2014-01-06 12:55:46 -0800 | [diff] [blame] | 63 | bool low_4gb, std::string* error_msg); |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 64 | |
| 65 | // Map part of a file, taking care of non-page aligned offsets. The |
| 66 | // "start" offset is absolute, not relative. |
| 67 | // |
| 68 | // On success, returns returns a MemMap instance. On failure, returns a NULL; |
Ian Rogers | 8d31bbd | 2013-10-13 10:44:14 -0700 | [diff] [blame] | 69 | static MemMap* MapFile(size_t byte_count, int prot, int flags, int fd, off_t start, |
| 70 | const char* filename, std::string* error_msg) { |
| 71 | return MapFileAtAddress(NULL, byte_count, prot, flags, fd, start, false, filename, error_msg); |
Brian Carlstrom | 4a289ed | 2011-08-16 17:17:49 -0700 | [diff] [blame] | 72 | } |
| 73 | |
| 74 | // Map part of a file, taking care of non-page aligned offsets. The |
| 75 | // "start" offset is absolute, not relative. This version allows |
| 76 | // requesting a specific address for the base of the mapping. |
| 77 | // |
| 78 | // On success, returns returns a MemMap instance. On failure, returns a NULL; |
Ian Rogers | 8d31bbd | 2013-10-13 10:44:14 -0700 | [diff] [blame] | 79 | static MemMap* MapFileAtAddress(byte* addr, size_t byte_count, int prot, int flags, int fd, |
| 80 | off_t start, bool reuse, const char* filename, |
| 81 | std::string* error_msg); |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 82 | |
Brian Carlstrom | 27ec961 | 2011-09-19 20:20:38 -0700 | [diff] [blame] | 83 | // Releases the memory mapping |
Hiroshi Yamauchi | 3eed93d | 2014-06-04 11:43:59 -0700 | [diff] [blame] | 84 | ~MemMap() LOCKS_EXCLUDED(Locks::mem_maps_lock_); |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 85 | |
Brian Carlstrom | 0d6adac | 2014-02-05 17:39:16 -0800 | [diff] [blame] | 86 | const std::string& GetName() const { |
| 87 | return name_; |
| 88 | } |
| 89 | |
Logan Chien | d88fa26 | 2012-06-06 15:23:32 +0800 | [diff] [blame] | 90 | bool Protect(int prot); |
| 91 | |
Ian Rogers | c5f1773 | 2014-06-05 20:48:42 -0700 | [diff] [blame] | 92 | void MadviseDontNeedAndZero(); |
| 93 | |
Ian Rogers | 1c849e5 | 2012-06-28 14:00:33 -0700 | [diff] [blame] | 94 | int GetProtect() const { |
| 95 | return prot_; |
| 96 | } |
| 97 | |
Ian Rogers | 30fab40 | 2012-01-23 15:43:46 -0800 | [diff] [blame] | 98 | byte* Begin() const { |
| 99 | return begin_; |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 100 | } |
| 101 | |
Ian Rogers | 30fab40 | 2012-01-23 15:43:46 -0800 | [diff] [blame] | 102 | size_t Size() const { |
| 103 | return size_; |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 104 | } |
| 105 | |
Ian Rogers | 30fab40 | 2012-01-23 15:43:46 -0800 | [diff] [blame] | 106 | byte* End() const { |
Mathieu Chartier | 2fde533 | 2012-09-14 14:51:54 -0700 | [diff] [blame] | 107 | return Begin() + Size(); |
| 108 | } |
| 109 | |
Brian Carlstrom | 0d6adac | 2014-02-05 17:39:16 -0800 | [diff] [blame] | 110 | void* BaseBegin() const { |
| 111 | return base_begin_; |
| 112 | } |
| 113 | |
| 114 | size_t BaseSize() const { |
| 115 | return base_size_; |
| 116 | } |
| 117 | |
| 118 | void* BaseEnd() const { |
| 119 | return reinterpret_cast<byte*>(BaseBegin()) + BaseSize(); |
| 120 | } |
| 121 | |
Mathieu Chartier | 2fde533 | 2012-09-14 14:51:54 -0700 | [diff] [blame] | 122 | bool HasAddress(const void* addr) const { |
| 123 | return Begin() <= addr && addr < End(); |
Brian Carlstrom | b765be0 | 2011-08-17 23:54:10 -0700 | [diff] [blame] | 124 | } |
| 125 | |
Hiroshi Yamauchi | fd7e7f1 | 2013-10-22 14:17:48 -0700 | [diff] [blame] | 126 | // Unmap the pages at end and remap them to create another memory map. |
| 127 | MemMap* RemapAtEnd(byte* new_end, const char* tail_name, int tail_prot, |
| 128 | std::string* error_msg); |
Mathieu Chartier | cc236d7 | 2012-07-20 10:29:05 -0700 | [diff] [blame] | 129 | |
Hiroshi Yamauchi | 3eed93d | 2014-06-04 11:43:59 -0700 | [diff] [blame] | 130 | static bool CheckNoGaps(MemMap* begin_map, MemMap* end_map) |
| 131 | LOCKS_EXCLUDED(Locks::mem_maps_lock_); |
| 132 | static void DumpMaps(std::ostream& os) |
| 133 | LOCKS_EXCLUDED(Locks::mem_maps_lock_); |
| 134 | |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 135 | private: |
Mathieu Chartier | 1c23e1e | 2012-10-12 14:14:11 -0700 | [diff] [blame] | 136 | MemMap(const std::string& name, byte* begin, size_t size, void* base_begin, size_t base_size, |
Hiroshi Yamauchi | 3eed93d | 2014-06-04 11:43:59 -0700 | [diff] [blame] | 137 | int prot) LOCKS_EXCLUDED(Locks::mem_maps_lock_); |
| 138 | |
| 139 | static void DumpMaps(std::ostream& os, const std::multimap<void*, MemMap*>& mem_maps) |
| 140 | LOCKS_EXCLUDED(Locks::mem_maps_lock_); |
| 141 | static void DumpMapsLocked(std::ostream& os, const std::multimap<void*, MemMap*>& mem_maps) |
| 142 | EXCLUSIVE_LOCKS_REQUIRED(Locks::mem_maps_lock_); |
| 143 | static bool HasMemMap(MemMap* map) |
| 144 | EXCLUSIVE_LOCKS_REQUIRED(Locks::mem_maps_lock_); |
| 145 | static MemMap* GetLargestMemMapAt(void* address) |
| 146 | EXCLUSIVE_LOCKS_REQUIRED(Locks::mem_maps_lock_); |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 147 | |
Mathieu Chartier | 1c23e1e | 2012-10-12 14:14:11 -0700 | [diff] [blame] | 148 | std::string name_; |
Ian Rogers | 1c849e5 | 2012-06-28 14:00:33 -0700 | [diff] [blame] | 149 | byte* const begin_; // Start of data. |
Mathieu Chartier | cc236d7 | 2012-07-20 10:29:05 -0700 | [diff] [blame] | 150 | size_t size_; // Length of data. |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 151 | |
Ian Rogers | 1c849e5 | 2012-06-28 14:00:33 -0700 | [diff] [blame] | 152 | void* const base_begin_; // Page-aligned base address. |
Hiroshi Yamauchi | fd7e7f1 | 2013-10-22 14:17:48 -0700 | [diff] [blame] | 153 | size_t base_size_; // Length of mapping. May be changed by RemapAtEnd (ie Zygote). |
Ian Rogers | 1c849e5 | 2012-06-28 14:00:33 -0700 | [diff] [blame] | 154 | int prot_; // Protection of the map. |
Hiroshi Yamauchi | fd7e7f1 | 2013-10-22 14:17:48 -0700 | [diff] [blame] | 155 | |
Ian Rogers | c3ccc10 | 2014-06-25 11:52:14 -0700 | [diff] [blame] | 156 | #if USE_ART_LOW_4G_ALLOCATOR |
| 157 | static uintptr_t next_mem_pos_; // Next memory location to check for low_4g extent. |
Stuart Monteith | 8dba5aa | 2014-03-12 12:44:01 +0000 | [diff] [blame] | 158 | #endif |
| 159 | |
Hiroshi Yamauchi | 3eed93d | 2014-06-04 11:43:59 -0700 | [diff] [blame] | 160 | // All the non-empty MemMaps. Use a multimap as we do a reserve-and-divide (eg ElfMap::Load()). |
| 161 | static std::multimap<void*, MemMap*> maps_ GUARDED_BY(Locks::mem_maps_lock_); |
| 162 | |
Hiroshi Yamauchi | fd7e7f1 | 2013-10-22 14:17:48 -0700 | [diff] [blame] | 163 | friend class MemMapTest; // To allow access to base_begin_ and base_size_. |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 164 | }; |
Brian Carlstrom | 0d6adac | 2014-02-05 17:39:16 -0800 | [diff] [blame] | 165 | std::ostream& operator<<(std::ostream& os, const MemMap& mem_map); |
Brian Carlstrom | db4d540 | 2011-08-09 12:18:28 -0700 | [diff] [blame] | 166 | |
| 167 | } // namespace art |
| 168 | |
Brian Carlstrom | fc0e321 | 2013-07-17 14:40:12 -0700 | [diff] [blame] | 169 | #endif // ART_RUNTIME_MEM_MAP_H_ |