2 * Copyright (C) 2008 Apple Inc. All rights reserved.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 #include "ExecutableAllocator.h"
34 #include <wtf/VMTags.h>
38 #if !(PLATFORM(MAC) && PLATFORM(X86_64))
40 void ExecutableAllocator::intializePageSize()
42 ExecutableAllocator::pageSize
= getpagesize();
45 ExecutablePool::Allocation
ExecutablePool::systemAlloc(size_t n
)
47 ExecutablePool::Allocation alloc
= { reinterpret_cast<char*>(mmap(NULL
, n
, INITIAL_PROTECTION_FLAGS
, MAP_PRIVATE
| MAP_ANON
, VM_TAG_FOR_EXECUTABLEALLOCATOR_MEMORY
, 0)), n
};
51 void ExecutablePool::systemRelease(const ExecutablePool::Allocation
& alloc
)
53 int result
= munmap(alloc
.pages
, alloc
.size
);
54 ASSERT_UNUSED(result
, !result
);
57 #endif // !(PLATFORM(MAC) && PLATFORM(X86_64))
59 #if ENABLE(ASSEMBLER_WX_EXCLUSIVE)
60 void ExecutableAllocator::reprotectRegion(void* start
, size_t size
, ProtectionSeting setting
)
65 // Calculate the start of the page containing this region,
66 // and account for this extra memory within size.
67 intptr_t startPtr
= reinterpret_cast<intptr_t>(start
);
68 intptr_t pageStartPtr
= startPtr
& ~(pageSize
- 1);
69 void* pageStart
= reinterpret_cast<void*>(pageStartPtr
);
70 size
+= (startPtr
- pageStartPtr
);
73 size
+= (pageSize
- 1);
74 size
&= ~(pageSize
- 1);
76 mprotect(pageStart
, size
, (setting
== Writable
) ? PROTECTION_FLAGS_RW
: PROTECTION_FLAGS_RX
);
82 #endif // HAVE(ASSEMBLER)