mem_map.h revision 90443477f9a0061581c420775ce3b7eeae7468bc
1db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom/* 2db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom * Copyright (C) 2008 The Android Open Source Project 3db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom * 4db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom * Licensed under the Apache License, Version 2.0 (the "License"); 5db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom * you may not use this file except in compliance with the License. 6db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom * You may obtain a copy of the License at 7db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom * 8db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom * http://www.apache.org/licenses/LICENSE-2.0 9db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom * 10db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom * Unless required by applicable law or agreed to in writing, software 11db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom * distributed under the License is distributed on an "AS IS" BASIS, 12db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom * See the License for the specific language governing permissions and 14db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom * limitations under the License. 15db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom */ 16db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 17fc0e3219edc9a5bf81b166e82fd5db2796eb6a0dBrian Carlstrom#ifndef ART_RUNTIME_MEM_MAP_H_ 18fc0e3219edc9a5bf81b166e82fd5db2796eb6a0dBrian Carlstrom#define ART_RUNTIME_MEM_MAP_H_ 19db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 203eed93dd5be03e5539827bebf0f414251a12e15eHiroshi Yamauchi#include "base/mutex.h" 213eed93dd5be03e5539827bebf0f414251a12e15eHiroshi Yamauchi 221c23e1edb7361bbaec6e57fca86d8d3797960ad2Mathieu Chartier#include <string> 233eed93dd5be03e5539827bebf0f414251a12e15eHiroshi Yamauchi#include <map> 241c23e1edb7361bbaec6e57fca86d8d3797960ad2Mathieu Chartier 2527ec961a1da540ba7f16c07a682585ab167317adBrian Carlstrom#include <stddef.h> 26a168c83a1d247094e9efb1244b0f73a5f1e1ed97Elliott Hughes#include <sys/mman.h> // For the PROT_* and MAP_* constants. 2727ec961a1da540ba7f16c07a682585ab167317adBrian Carlstrom#include <sys/types.h> 28db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 29bad0267eaab9d6a522d05469ff90501deefdb88bMathieu Chartier#include "base/allocator.h" 3027ec961a1da540ba7f16c07a682585ab167317adBrian Carlstrom#include "globals.h" 31db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 32db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstromnamespace art { 33db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 34c3ccc1039e0bbc0744f958cb8719cf96bce5b853Ian Rogers#if defined(__LP64__) && (!defined(__x86_64__) || defined(__APPLE__)) 35c3ccc1039e0bbc0744f958cb8719cf96bce5b853Ian Rogers#define USE_ART_LOW_4G_ALLOCATOR 1 36c3ccc1039e0bbc0744f958cb8719cf96bce5b853Ian Rogers#else 37c3ccc1039e0bbc0744f958cb8719cf96bce5b853Ian Rogers#define USE_ART_LOW_4G_ALLOCATOR 0 38c3ccc1039e0bbc0744f958cb8719cf96bce5b853Ian Rogers#endif 39c3ccc1039e0bbc0744f958cb8719cf96bce5b853Ian Rogers 40c5f17732d8144491c642776b6b48c85dfadf4b52Ian Rogers#ifdef __linux__ 41c5f17732d8144491c642776b6b48c85dfadf4b52Ian Rogersstatic constexpr bool kMadviseZeroes = true; 42c5f17732d8144491c642776b6b48c85dfadf4b52Ian Rogers#else 43c5f17732d8144491c642776b6b48c85dfadf4b52Ian Rogersstatic constexpr bool kMadviseZeroes = false; 44c5f17732d8144491c642776b6b48c85dfadf4b52Ian Rogers#endif 45c5f17732d8144491c642776b6b48c85dfadf4b52Ian Rogers 46db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom// Used to keep track of mmap segments. 47d8f26dbebe72c1cbdfa85bdeeb003283c7435db3Andreas Gampe// 48d8f26dbebe72c1cbdfa85bdeeb003283c7435db3Andreas Gampe// On 64b systems not supporting MAP_32BIT, the implementation of MemMap will do a linear scan 49d8f26dbebe72c1cbdfa85bdeeb003283c7435db3Andreas Gampe// for free pages. For security, the start of this scan should be randomized. This requires a 50d8f26dbebe72c1cbdfa85bdeeb003283c7435db3Andreas Gampe// dynamic initializer. 51d8f26dbebe72c1cbdfa85bdeeb003283c7435db3Andreas Gampe// For this to work, it is paramount that there are no other static initializers that access MemMap. 52d8f26dbebe72c1cbdfa85bdeeb003283c7435db3Andreas Gampe// Otherwise, calls might see uninitialized values. 53db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstromclass MemMap { 54db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom public: 55ecd3a6fc6e29d7dc4cb825c5282a8054ac52b8cfElliott Hughes // Request an anonymous region of length 'byte_count' and a requested base address. 562cebb24bfc3247d3e9be138a3350106737455918Mathieu Chartier // Use null as the requested base address if you don't care. 575c42c29b89286e5efa4a4613132b09051ce5945bVladimir Marko // "reuse" allows re-mapping an address range from an existing mapping. 586c9c06dbb0b16714079afaedbebd3d548aa832b2Elliott Hughes // 596c9c06dbb0b16714079afaedbebd3d548aa832b2Elliott Hughes // The word "anonymous" in this context means "not backed by a file". The supplied 606c9c06dbb0b16714079afaedbebd3d548aa832b2Elliott Hughes // 'ashmem_name' will be used -- on systems that support it -- to give the mapping 616c9c06dbb0b16714079afaedbebd3d548aa832b2Elliott Hughes // a name. 624a289ed61242964b921434de7d375f46480472a1Brian Carlstrom // 632cebb24bfc3247d3e9be138a3350106737455918Mathieu Chartier // On success, returns returns a MemMap instance. On failure, returns null. 6413735955f39b3b304c37d2b2840663c131262c18Ian Rogers static MemMap* MapAnonymous(const char* ashmem_name, uint8_t* addr, size_t byte_count, int prot, 655c42c29b89286e5efa4a4613132b09051ce5945bVladimir Marko bool low_4gb, bool reuse, std::string* error_msg); 66db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 671baabf0726eb285284e0c908ccba9f209b399faeDavid Srbecky // Create placeholder for a region allocated by direct call to mmap. 681baabf0726eb285284e0c908ccba9f209b399faeDavid Srbecky // This is useful when we do not have control over the code calling mmap, 691baabf0726eb285284e0c908ccba9f209b399faeDavid Srbecky // but when we still want to keep track of it in the list. 701baabf0726eb285284e0c908ccba9f209b399faeDavid Srbecky // The region is not considered to be owned and will not be unmmaped. 711baabf0726eb285284e0c908ccba9f209b399faeDavid Srbecky static MemMap* MapDummy(const char* name, uint8_t* addr, size_t byte_count); 721baabf0726eb285284e0c908ccba9f209b399faeDavid Srbecky 73db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom // Map part of a file, taking care of non-page aligned offsets. The 74db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom // "start" offset is absolute, not relative. 75db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom // 762cebb24bfc3247d3e9be138a3350106737455918Mathieu Chartier // On success, returns returns a MemMap instance. On failure, returns null. 778d31bbd3d6536de12bc20e3d29cfe03fe848f9daIan Rogers static MemMap* MapFile(size_t byte_count, int prot, int flags, int fd, off_t start, 788d31bbd3d6536de12bc20e3d29cfe03fe848f9daIan Rogers const char* filename, std::string* error_msg) { 792cebb24bfc3247d3e9be138a3350106737455918Mathieu Chartier return MapFileAtAddress( 802cebb24bfc3247d3e9be138a3350106737455918Mathieu Chartier nullptr, byte_count, prot, flags, fd, start, false, filename, error_msg); 814a289ed61242964b921434de7d375f46480472a1Brian Carlstrom } 824a289ed61242964b921434de7d375f46480472a1Brian Carlstrom 834a289ed61242964b921434de7d375f46480472a1Brian Carlstrom // Map part of a file, taking care of non-page aligned offsets. The 844a289ed61242964b921434de7d375f46480472a1Brian Carlstrom // "start" offset is absolute, not relative. This version allows 85a62a588a9202f69e53fbeb3045ea8ea5ec2587f8Jim_Guo // requesting a specific address for the base of the 86a62a588a9202f69e53fbeb3045ea8ea5ec2587f8Jim_Guo // mapping. "reuse" allows us to create a view into an existing 87a62a588a9202f69e53fbeb3045ea8ea5ec2587f8Jim_Guo // mapping where we do not take ownership of the memory. 884a289ed61242964b921434de7d375f46480472a1Brian Carlstrom // 892cebb24bfc3247d3e9be138a3350106737455918Mathieu Chartier // On success, returns returns a MemMap instance. On failure, returns null. 9013735955f39b3b304c37d2b2840663c131262c18Ian Rogers static MemMap* MapFileAtAddress(uint8_t* addr, size_t byte_count, int prot, int flags, int fd, 918d31bbd3d6536de12bc20e3d29cfe03fe848f9daIan Rogers off_t start, bool reuse, const char* filename, 928d31bbd3d6536de12bc20e3d29cfe03fe848f9daIan Rogers std::string* error_msg); 93db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 942cebb24bfc3247d3e9be138a3350106737455918Mathieu Chartier // Releases the memory mapping. 9590443477f9a0061581c420775ce3b7eeae7468bcMathieu Chartier ~MemMap() REQUIRES(!Locks::mem_maps_lock_); 96db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 970d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom const std::string& GetName() const { 980d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom return name_; 990d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom } 1000d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom 101d88fa26892ad5ddebb7ab3407cdc574c54ed8258Logan Chien bool Protect(int prot); 102d88fa26892ad5ddebb7ab3407cdc574c54ed8258Logan Chien 103c5f17732d8144491c642776b6b48c85dfadf4b52Ian Rogers void MadviseDontNeedAndZero(); 104c5f17732d8144491c642776b6b48c85dfadf4b52Ian Rogers 1051c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers int GetProtect() const { 1061c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers return prot_; 1071c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers } 1081c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers 10913735955f39b3b304c37d2b2840663c131262c18Ian Rogers uint8_t* Begin() const { 11030fab40ee5a07af6b8c3b6b0e9438071695a57f4Ian Rogers return begin_; 111db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom } 112db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 11330fab40ee5a07af6b8c3b6b0e9438071695a57f4Ian Rogers size_t Size() const { 11430fab40ee5a07af6b8c3b6b0e9438071695a57f4Ian Rogers return size_; 115db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom } 116db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 117379d09fe3c3feb7c2a2fb5a3623689b5ace7e79bMathieu Chartier // Resize the mem-map by unmapping pages at the end. Currently only supports shrinking. 118379d09fe3c3feb7c2a2fb5a3623689b5ace7e79bMathieu Chartier void SetSize(size_t new_size); 119379d09fe3c3feb7c2a2fb5a3623689b5ace7e79bMathieu Chartier 12013735955f39b3b304c37d2b2840663c131262c18Ian Rogers uint8_t* End() const { 1212fde53367dbe721e5273c34b590e67112322cc9eMathieu Chartier return Begin() + Size(); 1222fde53367dbe721e5273c34b590e67112322cc9eMathieu Chartier } 1232fde53367dbe721e5273c34b590e67112322cc9eMathieu Chartier 1240d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom void* BaseBegin() const { 1250d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom return base_begin_; 1260d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom } 1270d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom 1280d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom size_t BaseSize() const { 1290d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom return base_size_; 1300d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom } 1310d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom 1320d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom void* BaseEnd() const { 13313735955f39b3b304c37d2b2840663c131262c18Ian Rogers return reinterpret_cast<uint8_t*>(BaseBegin()) + BaseSize(); 1340d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom } 1350d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstrom 1362fde53367dbe721e5273c34b590e67112322cc9eMathieu Chartier bool HasAddress(const void* addr) const { 1372fde53367dbe721e5273c34b590e67112322cc9eMathieu Chartier return Begin() <= addr && addr < End(); 138b765be0d656c3073402693aeaf64e95a0e49f218Brian Carlstrom } 139b765be0d656c3073402693aeaf64e95a0e49f218Brian Carlstrom 140fd7e7f1253927c8d7f17e7cbc259daaf51868bd3Hiroshi Yamauchi // Unmap the pages at end and remap them to create another memory map. 14113735955f39b3b304c37d2b2840663c131262c18Ian Rogers MemMap* RemapAtEnd(uint8_t* new_end, const char* tail_name, int tail_prot, 142fd7e7f1253927c8d7f17e7cbc259daaf51868bd3Hiroshi Yamauchi std::string* error_msg); 143cc236d74772dda5a4161d9bc5f497fd3d956eb87Mathieu Chartier 1443eed93dd5be03e5539827bebf0f414251a12e15eHiroshi Yamauchi static bool CheckNoGaps(MemMap* begin_map, MemMap* end_map) 14590443477f9a0061581c420775ce3b7eeae7468bcMathieu Chartier REQUIRES(!Locks::mem_maps_lock_); 14617a924abde2b0f1f37f6008b451a0a75190c71ffVladimir Marko static void DumpMaps(std::ostream& os, bool terse = false) 14790443477f9a0061581c420775ce3b7eeae7468bcMathieu Chartier REQUIRES(!Locks::mem_maps_lock_); 1483eed93dd5be03e5539827bebf0f414251a12e15eHiroshi Yamauchi 149bad0267eaab9d6a522d05469ff90501deefdb88bMathieu Chartier typedef AllocationTrackingMultiMap<void*, MemMap*, kAllocatorTagMaps> Maps; 150bad0267eaab9d6a522d05469ff90501deefdb88bMathieu Chartier 15190443477f9a0061581c420775ce3b7eeae7468bcMathieu Chartier static void Init() REQUIRES(!Locks::mem_maps_lock_); 15290443477f9a0061581c420775ce3b7eeae7468bcMathieu Chartier static void Shutdown() REQUIRES(!Locks::mem_maps_lock_); 1536e88ef6b604a7a945a466784580c42e6554c1289Mathieu Chartier 154db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom private: 15513735955f39b3b304c37d2b2840663c131262c18Ian Rogers MemMap(const std::string& name, uint8_t* begin, size_t size, void* base_begin, size_t base_size, 15690443477f9a0061581c420775ce3b7eeae7468bcMathieu Chartier int prot, bool reuse, size_t redzone_size = 0) REQUIRES(!Locks::mem_maps_lock_); 1573eed93dd5be03e5539827bebf0f414251a12e15eHiroshi Yamauchi 15817a924abde2b0f1f37f6008b451a0a75190c71ffVladimir Marko static void DumpMapsLocked(std::ostream& os, bool terse) 15990443477f9a0061581c420775ce3b7eeae7468bcMathieu Chartier REQUIRES(Locks::mem_maps_lock_); 1603eed93dd5be03e5539827bebf0f414251a12e15eHiroshi Yamauchi static bool HasMemMap(MemMap* map) 16190443477f9a0061581c420775ce3b7eeae7468bcMathieu Chartier REQUIRES(Locks::mem_maps_lock_); 1623eed93dd5be03e5539827bebf0f414251a12e15eHiroshi Yamauchi static MemMap* GetLargestMemMapAt(void* address) 16390443477f9a0061581c420775ce3b7eeae7468bcMathieu Chartier REQUIRES(Locks::mem_maps_lock_); 164db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 165a62a588a9202f69e53fbeb3045ea8ea5ec2587f8Jim_Guo const std::string name_; 16613735955f39b3b304c37d2b2840663c131262c18Ian Rogers uint8_t* const begin_; // Start of data. 167cc236d74772dda5a4161d9bc5f497fd3d956eb87Mathieu Chartier size_t size_; // Length of data. 168db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 1691c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers void* const base_begin_; // Page-aligned base address. 170fd7e7f1253927c8d7f17e7cbc259daaf51868bd3Hiroshi Yamauchi size_t base_size_; // Length of mapping. May be changed by RemapAtEnd (ie Zygote). 1711c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers int prot_; // Protection of the map. 172fd7e7f1253927c8d7f17e7cbc259daaf51868bd3Hiroshi Yamauchi 173a62a588a9202f69e53fbeb3045ea8ea5ec2587f8Jim_Guo // When reuse_ is true, this is just a view of an existing mapping 174a62a588a9202f69e53fbeb3045ea8ea5ec2587f8Jim_Guo // and we do not take ownership and are not responsible for 175a62a588a9202f69e53fbeb3045ea8ea5ec2587f8Jim_Guo // unmapping. 176a62a588a9202f69e53fbeb3045ea8ea5ec2587f8Jim_Guo const bool reuse_; 177a62a588a9202f69e53fbeb3045ea8ea5ec2587f8Jim_Guo 1781e13374baf7dfaf442ffbf9809c37c131d681eafEvgenii Stepanov const size_t redzone_size_; 1791e13374baf7dfaf442ffbf9809c37c131d681eafEvgenii Stepanov 180c3ccc1039e0bbc0744f958cb8719cf96bce5b853Ian Rogers#if USE_ART_LOW_4G_ALLOCATOR 181c3ccc1039e0bbc0744f958cb8719cf96bce5b853Ian Rogers static uintptr_t next_mem_pos_; // Next memory location to check for low_4g extent. 1828dba5aaaffc0bc2b2580bf02f0d9095c00d26a17Stuart Monteith#endif 1838dba5aaaffc0bc2b2580bf02f0d9095c00d26a17Stuart Monteith 1843eed93dd5be03e5539827bebf0f414251a12e15eHiroshi Yamauchi // All the non-empty MemMaps. Use a multimap as we do a reserve-and-divide (eg ElfMap::Load()). 1856e88ef6b604a7a945a466784580c42e6554c1289Mathieu Chartier static Maps* maps_ GUARDED_BY(Locks::mem_maps_lock_); 1863eed93dd5be03e5539827bebf0f414251a12e15eHiroshi Yamauchi 187fd7e7f1253927c8d7f17e7cbc259daaf51868bd3Hiroshi Yamauchi friend class MemMapTest; // To allow access to base_begin_ and base_size_. 188db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom}; 1890d6adac2550113da33d42e88f0d87a57b25c5a60Brian Carlstromstd::ostream& operator<<(std::ostream& os, const MemMap& mem_map); 190277ccbd200ea43590dfc06a93ae184a765327ad0Andreas Gampestd::ostream& operator<<(std::ostream& os, const MemMap::Maps& mem_maps); 191db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 192db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom} // namespace art 193db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 194fc0e3219edc9a5bf81b166e82fd5db2796eb6a0dBrian Carlstrom#endif // ART_RUNTIME_MEM_MAP_H_ 195