1 | /* |
2 | * Copyright (C) 2008 Apple Inc. All rights reserved. |
3 | * |
4 | * Redistribution and use in source and binary forms, with or without |
5 | * modification, are permitted provided that the following conditions |
6 | * are met: |
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. |
12 | * |
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. |
24 | */ |
25 | |
26 | #include "config.h" |
27 | |
28 | #include "ExecutableAllocator.h" |
29 | |
30 | #if ENABLE(ASSEMBLER) |
31 | |
32 | namespace JSC { |
33 | |
34 | size_t ExecutableAllocator::pageSize = 0; |
35 | |
36 | #if ENABLE(ASSEMBLER_WX_EXCLUSIVE) |
37 | void ExecutableAllocator::reprotectRegion(void* start, size_t size, ProtectionSeting setting) |
38 | { |
39 | if (!pageSize) |
40 | intializePageSize(); |
41 | |
42 | // Calculate the start of the page containing this region, |
43 | // and account for this extra memory within size. |
44 | intptr_t startPtr = reinterpret_cast<intptr_t>(start); |
45 | intptr_t pageStartPtr = startPtr & ~(pageSize - 1); |
46 | void* pageStart = reinterpret_cast<void*>(pageStartPtr); |
47 | size += (startPtr - pageStartPtr); |
48 | |
49 | // Round size up |
50 | size += (pageSize - 1); |
51 | size &= ~(pageSize - 1); |
52 | |
53 | mprotect(pageStart, size, (setting == Writable) ? PROTECTION_FLAGS_RW : PROTECTION_FLAGS_RX); |
54 | } |
55 | #endif |
56 | |
57 | } |
58 | |
59 | #endif // HAVE(ASSEMBLER) |
60 | |