mem_map.h revision 2fde53367dbe721e5273c34b590e67112322cc9e
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 17db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom#ifndef ART_SRC_MEM_MAP_H_ 18db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom#define ART_SRC_MEM_MAP_H_ 19db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 2027ec961a1da540ba7f16c07a682585ab167317adBrian Carlstrom#include <stddef.h> 21a168c83a1d247094e9efb1244b0f73a5f1e1ed97Elliott Hughes#include <sys/mman.h> // For the PROT_* and MAP_* constants. 2227ec961a1da540ba7f16c07a682585ab167317adBrian Carlstrom#include <sys/types.h> 23db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 2427ec961a1da540ba7f16c07a682585ab167317adBrian Carlstrom#include "globals.h" 25db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 26db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstromnamespace art { 27db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 28db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom// Used to keep track of mmap segments. 29db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstromclass MemMap { 30db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom public: 31ecd3a6fc6e29d7dc4cb825c5282a8054ac52b8cfElliott Hughes // Request an anonymous region of length 'byte_count' and a requested base address. 326c9c06dbb0b16714079afaedbebd3d548aa832b2Elliott Hughes // Use NULL as the requested base address if you don't care. 336c9c06dbb0b16714079afaedbebd3d548aa832b2Elliott Hughes // 346c9c06dbb0b16714079afaedbebd3d548aa832b2Elliott Hughes // The word "anonymous" in this context means "not backed by a file". The supplied 356c9c06dbb0b16714079afaedbebd3d548aa832b2Elliott Hughes // 'ashmem_name' will be used -- on systems that support it -- to give the mapping 366c9c06dbb0b16714079afaedbebd3d548aa832b2Elliott Hughes // a name. 374a289ed61242964b921434de7d375f46480472a1Brian Carlstrom // 384a289ed61242964b921434de7d375f46480472a1Brian Carlstrom // On success, returns returns a MemMap instance. On failure, returns a NULL; 39ecd3a6fc6e29d7dc4cb825c5282a8054ac52b8cfElliott Hughes static MemMap* MapAnonymous(const char* ashmem_name, byte* addr, size_t byte_count, int prot); 40db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 41db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom // Map part of a file, taking care of non-page aligned offsets. The 42db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom // "start" offset is absolute, not relative. 43db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom // 44db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom // On success, returns returns a MemMap instance. On failure, returns a NULL; 45ecd3a6fc6e29d7dc4cb825c5282a8054ac52b8cfElliott Hughes static MemMap* MapFile(size_t byte_count, int prot, int flags, int fd, off_t start) { 46ecd3a6fc6e29d7dc4cb825c5282a8054ac52b8cfElliott Hughes return MapFileAtAddress(NULL, byte_count, prot, flags, fd, start); 474a289ed61242964b921434de7d375f46480472a1Brian Carlstrom } 484a289ed61242964b921434de7d375f46480472a1Brian Carlstrom 494a289ed61242964b921434de7d375f46480472a1Brian Carlstrom // Map part of a file, taking care of non-page aligned offsets. The 504a289ed61242964b921434de7d375f46480472a1Brian Carlstrom // "start" offset is absolute, not relative. This version allows 514a289ed61242964b921434de7d375f46480472a1Brian Carlstrom // requesting a specific address for the base of the mapping. 524a289ed61242964b921434de7d375f46480472a1Brian Carlstrom // 534a289ed61242964b921434de7d375f46480472a1Brian Carlstrom // On success, returns returns a MemMap instance. On failure, returns a NULL; 5489521898b56f2ebc3fb68acfb6bc6dde9b6f5c38Brian Carlstrom static MemMap* MapFileAtAddress( 55ecd3a6fc6e29d7dc4cb825c5282a8054ac52b8cfElliott Hughes byte* addr, size_t byte_count, int prot, int flags, int fd, off_t start); 56db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 5727ec961a1da540ba7f16c07a682585ab167317adBrian Carlstrom // Releases the memory mapping 5827ec961a1da540ba7f16c07a682585ab167317adBrian Carlstrom ~MemMap(); 59db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 60d88fa26892ad5ddebb7ab3407cdc574c54ed8258Logan Chien bool Protect(int prot); 61d88fa26892ad5ddebb7ab3407cdc574c54ed8258Logan Chien 621c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers int GetProtect() const { 631c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers return prot_; 641c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers } 651c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers 6630fab40ee5a07af6b8c3b6b0e9438071695a57f4Ian Rogers byte* Begin() const { 6730fab40ee5a07af6b8c3b6b0e9438071695a57f4Ian Rogers return begin_; 68db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom } 69db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 7030fab40ee5a07af6b8c3b6b0e9438071695a57f4Ian Rogers size_t Size() const { 7130fab40ee5a07af6b8c3b6b0e9438071695a57f4Ian Rogers return size_; 72db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom } 73db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 7430fab40ee5a07af6b8c3b6b0e9438071695a57f4Ian Rogers byte* End() const { 752fde53367dbe721e5273c34b590e67112322cc9eMathieu Chartier return Begin() + Size(); 762fde53367dbe721e5273c34b590e67112322cc9eMathieu Chartier } 772fde53367dbe721e5273c34b590e67112322cc9eMathieu Chartier 782fde53367dbe721e5273c34b590e67112322cc9eMathieu Chartier bool HasAddress(const void* addr) const { 792fde53367dbe721e5273c34b590e67112322cc9eMathieu Chartier return Begin() <= addr && addr < End(); 80b765be0d656c3073402693aeaf64e95a0e49f218Brian Carlstrom } 81b765be0d656c3073402693aeaf64e95a0e49f218Brian Carlstrom 82cc236d74772dda5a4161d9bc5f497fd3d956eb87Mathieu Chartier // Trim by unmapping pages at the end of the map. 83cc236d74772dda5a4161d9bc5f497fd3d956eb87Mathieu Chartier void UnMapAtEnd(byte* new_end); 84cc236d74772dda5a4161d9bc5f497fd3d956eb87Mathieu Chartier 85db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom private: 861c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers MemMap(byte* begin, size_t size, void* base_begin, size_t base_size, int prot); 87db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 881c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers byte* const begin_; // Start of data. 89cc236d74772dda5a4161d9bc5f497fd3d956eb87Mathieu Chartier size_t size_; // Length of data. 90db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 911c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers void* const base_begin_; // Page-aligned base address. 921c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers const size_t base_size_; // Length of mapping. 931c849e5badc85b6753dee0c0487729b2c0529f51Ian Rogers int prot_; // Protection of the map. 94db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom}; 95db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 96db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom} // namespace art 97db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom 98db4d54081f09abcbe97ffdf615874f2809a9e777Brian Carlstrom#endif // ART_SRC_MEM_MAP_H_ 99