diff options
author | Dylan Baker <[email protected]> | 2018-11-09 10:40:15 -0800 |
---|---|---|
committer | Rob Clark <[email protected]> | 2018-11-27 15:44:02 -0500 |
commit | 88c4680b5a50ea8840c38aa0a80acde63ef1677b (patch) | |
tree | 091b7d017b915fcdafd315288a2114a8169c3a3f /src/util/os_memory_aligned.h | |
parent | bade179153b10300129c93afb1e629d9814c122e (diff) |
util: promote u_memory to src/util
as well as os_memory*
Reviewed-by: Rob Clark <[email protected]>
Diffstat (limited to 'src/util/os_memory_aligned.h')
-rw-r--r-- | src/util/os_memory_aligned.h | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/src/util/os_memory_aligned.h b/src/util/os_memory_aligned.h new file mode 100644 index 00000000000..df398a32bfd --- /dev/null +++ b/src/util/os_memory_aligned.h @@ -0,0 +1,98 @@ +/************************************************************************** + * + * Copyright 2008-2010 VMware, Inc. + * All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sub license, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. + * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR + * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, + * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE + * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + **************************************************************************/ + + +/* + * Memory alignment wrappers. + */ + + +#ifndef _OS_MEMORY_H_ +#error "Must not be included directly. Include os_memory.h instead" +#endif + + +#include "pipe/p_compiler.h" + + + +/** + * Add two size_t values with integer overflow check. + * TODO: leverage __builtin_add_overflow where available + */ +static inline bool +add_overflow_size_t(size_t a, size_t b, size_t *res) +{ + *res = a + b; + return *res < a || *res < b; +} + + +/** + * Return memory on given byte alignment + */ +static inline void * +os_malloc_aligned(size_t size, size_t alignment) +{ + char *ptr, *buf; + size_t alloc_size; + + /* + * Calculate + * + * alloc_size = size + alignment + sizeof(void *) + * + * while checking for overflow. + */ + if (add_overflow_size_t(size, alignment, &alloc_size) || + add_overflow_size_t(alloc_size, sizeof(void *), &alloc_size)) { + return NULL; + } + + ptr = (char *) os_malloc(alloc_size); + if (!ptr) + return NULL; + + buf = (char *)(((uintptr_t)ptr + sizeof(void *) + alignment - 1) & ~((uintptr_t)(alignment - 1))); + *(char **)(buf - sizeof(void *)) = ptr; + + return buf; +} + + +/** + * Free memory returned by os_malloc_aligned(). + */ +static inline void +os_free_aligned(void *ptr) +{ + if (ptr) { + void **cubbyHole = (void **) ((char *) ptr - sizeof(void *)); + void *realAddr = *cubbyHole; + os_free(realAddr); + } +} |