1 /**************************************************************************
2 *
3 * Copyright 2008-2010 VMware, Inc.
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27
28
29 /*
30 * Memory alignment wrappers.
31 */
32
33
34 #ifndef _OS_MEMORY_H_
35 #error "Must not be included directly. Include os_memory.h instead"
36 #endif
37
38
39 #include "pipe/p_compiler.h"
40
41
42 /**
43 * Return memory on given byte alignment
44 */
45 static INLINE void *
os_malloc_aligned(size_t size,size_t alignment)46 os_malloc_aligned(size_t size, size_t alignment)
47 {
48 char *ptr, *buf;
49
50 ptr = (char *) os_malloc(size + alignment + sizeof(void *));
51 if (!ptr)
52 return NULL;
53
54 buf = (char *)(((uintptr_t)ptr + sizeof(void *) + alignment - 1) & ~((uintptr_t)(alignment - 1)));
55 *(char **)(buf - sizeof(void *)) = ptr;
56
57 return buf;
58 }
59
60
61 /**
62 * Free memory returned by align_malloc().
63 */
64 static INLINE void
os_free_aligned(void * ptr)65 os_free_aligned(void *ptr)
66 {
67 if (ptr) {
68 void **cubbyHole = (void **) ((char *) ptr - sizeof(void *));
69 void *realAddr = *cubbyHole;
70 os_free(realAddr);
71 }
72 }
73