1 /* 2 * Copyright (C) 2010 Apple Inc. All rights reserved. 3 * Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' 15 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 16 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 17 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS 18 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 19 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 20 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 21 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 22 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 23 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 24 * THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include "config.h" 28 #include "OSAllocator.h" 29 30 #include "PageAllocatorSymbian.h" 31 32 namespace WTF { 33 34 // Array to store code chunks used by JIT engine(s) 35 static RPointerArray<SymbianChunk> codeChunksContainer; 36 37 // The singleton data allocator (non code) 38 static PageAllocatorSymbian dataAllocator; 39 40 _LIT(KErrorStringInternalConsistency, "OSAllocator:ConsistencyError"); 41 _LIT(KErrorStringChunkCreation, "OSAllocator:ChunkInitError"); 42 _LIT(KErrorStringPageSize, "OSAllocator:WrongPageSize"); 43 44 // Makes a new code chunk for a JIT engine with everything in committed state 45 static void* allocateCodeChunk(size_t bytes) 46 { 47 RChunk c; 48 TInt error = c.CreateLocalCode(bytes, bytes); 49 __ASSERT_ALWAYS(error == KErrNone, User::Panic(KErrorStringChunkCreation, error)); 50 51 codeChunksContainer.Append(new SymbianChunk(c.Handle())); 52 return static_cast<void*>(c.Base()); 53 } 54 55 // Frees the _entire_ code chunk in which this address resides. 56 static bool deallocateCodeChunk(void* address) 57 { 58 bool found = false; 59 for (int i = 0; i < codeChunksContainer.Count(); i++) { 60 SymbianChunk* p = codeChunksContainer[i]; 61 if (p && p->contains(address)) { 62 codeChunksContainer.Remove(i); 63 delete p; 64 found = true; 65 } 66 } 67 return found; 68 } 69 70 // Return the (singleton) object that manages all non-code VM operations 71 static PageAllocatorSymbian* dataAllocatorInstance() 72 { 73 return &dataAllocator; 74 } 75 76 // Reserve memory and return the base address of the region 77 void* OSAllocator::reserveUncommitted(size_t reservationSize, Usage usage, bool , bool executable) 78 { 79 void* base = 0; 80 if (executable) 81 base = allocateCodeChunk(reservationSize); 82 else 83 base = dataAllocatorInstance()->reserve(reservationSize); 84 return base; 85 } 86 87 // Inverse operation of reserveUncommitted() 88 void OSAllocator::releaseDecommitted(void* parkedBase, size_t bytes) 89 { 90 if (dataAllocatorInstance()->contains(parkedBase)) 91 dataAllocatorInstance()->release(parkedBase, bytes); 92 93 // NOOP for code chunks (JIT) because we released them in decommit() 94 } 95 96 // Commit what was previously reserved via reserveUncommitted() 97 void OSAllocator::commit(void* address, size_t bytes, bool, bool executable) 98 { 99 // For code chunks, we commit (early) in reserveUncommitted(), so NOOP 100 // For data regions, do real work 101 if (!executable) 102 dataAllocatorInstance()->commit(address, bytes); 103 } 104 105 void OSAllocator::decommit(void* address, size_t bytes) 106 { 107 if (dataAllocatorInstance()->contains(address)) 108 dataAllocatorInstance()->decommit(address, bytes); 109 else 110 deallocateCodeChunk(address); // for code chunk, decommit AND release 111 } 112 113 void* OSAllocator::reserveAndCommit(size_t bytes, Usage usage, bool writable, bool executable) 114 { 115 void* base = reserveUncommitted(bytes, usage, writable, executable); 116 commit(base, bytes, writable, executable); 117 return base; 118 } 119 120 121 // The PageAllocatorSymbian class helps map OSAllocator calls for reserve/commit/decommit 122 // to a single large Symbian chunk. Only works with multiples of page size, and as a corollary 123 // all addresses accepted or returned by it are also page-sized aligned. 124 // Design notes: 125 // - We initialize a chunk up-front with a large reservation size 126 // - The entire reservation reserve is logically divided into pageSized blocks (4K on Symbian) 127 // - The map maintains 1 bit for each of the 4K-sized region in our address space 128 // - OSAllocator::reserveUncommitted() requests lead to 1 or more bits being set in map 129 // to indicate internally reserved state. The VM address corresponding to the first bit is returned. 130 // - OSAllocator::commit() actually calls RChunk.commit() and commits *all or part* of the region 131 // reserved via reserveUncommitted() previously. 132 // - OSAllocator::decommit() calls RChunk.decommit() 133 // - OSAllocator::releaseDecommitted() unparks all the bits in the map, but trusts that a previously 134 // call to decommit() would have returned the memory to the OS 135 PageAllocatorSymbian::PageAllocatorSymbian() 136 { 137 __ASSERT_ALWAYS(m_pageSize == WTF::pageSize(), User::Panic(KErrorStringPageSize, m_pageSize)); 138 139 RChunk chunk; 140 TInt error = chunk.CreateDisconnectedLocal(0, 0, TInt(largeReservationSize)); 141 __ASSERT_ALWAYS(error == KErrNone, User::Panic(KErrorStringChunkCreation, error)); 142 143 m_chunk = new SymbianChunk(chunk.Handle()); // takes ownership of chunk 144 } 145 146 PageAllocatorSymbian::~PageAllocatorSymbian() 147 { 148 delete m_chunk; 149 } 150 151 // Reserves a region internally in the bitmap 152 void* PageAllocatorSymbian::reserve(size_t bytes) 153 { 154 // Find first available region 155 const size_t nPages = bytes / m_pageSize; 156 const int64_t startIdx = m_map.findRunOfZeros(nPages); 157 158 // Pseudo OOM 159 if (startIdx < 0) 160 return 0; 161 162 for (size_t i = startIdx; i < startIdx + nPages ; i++) 163 m_map.set(i); 164 165 return static_cast<void*>( m_chunk->m_base + (TUint)(m_pageSize * startIdx) ); 166 } 167 168 // Reverses the effects of a reserve() call 169 void PageAllocatorSymbian::release(void* address, size_t bytes) 170 { 171 const size_t startIdx = (static_cast<char*>(address) - m_chunk->m_base) / m_pageSize; 172 const size_t nPages = bytes / m_pageSize; 173 for (size_t i = startIdx; i < startIdx + nPages ; i++) 174 m_map.clear(i); 175 } 176 177 // Actually commit memory from the OS, after a previous call to reserve() 178 bool PageAllocatorSymbian::commit(void* address, size_t bytes) 179 { 180 // sanity check that bits were previously set 181 const size_t idx = (static_cast<char*>(address) - m_chunk->m_base) / m_pageSize; 182 const size_t nPages = bytes / m_pageSize; 183 __ASSERT_ALWAYS(m_map.get(idx), User::Panic(KErrorStringInternalConsistency, idx)); 184 __ASSERT_ALWAYS(m_map.get(idx+nPages-1), User::Panic(KErrorStringInternalConsistency, idx+nPages-1)); 185 186 TInt error = m_chunk->Commit(static_cast<char*>(address) - m_chunk->m_base, bytes); 187 return (error == KErrNone); 188 } 189 190 // Inverse operation of commit(), a release() should follow later 191 bool PageAllocatorSymbian::decommit(void* address, size_t bytes) 192 { 193 TInt error = m_chunk->Decommit(static_cast<char*>(address) - m_chunk->m_base, bytes); 194 return (error == KErrNone); 195 } 196 197 bool PageAllocatorSymbian::contains(const void* address) const 198 { 199 return m_chunk->contains(address); 200 } 201 202 } // namespace WTF 203
