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a3860c1c5d
ULONG_MAX is often used to check for integer overflow when calculating allocation size. While ULONG_MAX happens to work on most systems, there is no guarantee that `size_t' must be the same size as `long'. This patch introduces SIZE_MAX, the maximum value of `size_t', to improve portability and readability for allocation size validation. Signed-off-by: Xi Wang <xi.wang@gmail.com> Acked-by: Alex Elder <elder@dreamhost.com> Cc: David Airlie <airlied@linux.ie> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
65 lines
2 KiB
C
65 lines
2 KiB
C
/*
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* Copyright © 2008 Intel Corporation
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the "Software"),
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* to deal in the Software without restriction, including without limitation
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* the rights to use, copy, modify, merge, publish, distribute, sublicense,
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* and/or sell copies of the Software, and to permit persons to whom the
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* Software is furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice (including the next
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* paragraph) shall be included in all copies or substantial portions of the
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* Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
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* IN THE SOFTWARE.
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*
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* Authors:
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* Jesse Barnes <jbarnes@virtuousgeek.org>
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*
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*/
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#ifndef _DRM_MEM_UTIL_H_
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#define _DRM_MEM_UTIL_H_
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#include <linux/vmalloc.h>
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static __inline__ void *drm_calloc_large(size_t nmemb, size_t size)
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{
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if (size != 0 && nmemb > SIZE_MAX / size)
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return NULL;
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if (size * nmemb <= PAGE_SIZE)
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return kcalloc(nmemb, size, GFP_KERNEL);
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return __vmalloc(size * nmemb,
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GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO, PAGE_KERNEL);
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}
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/* Modeled after cairo's malloc_ab, it's like calloc but without the zeroing. */
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static __inline__ void *drm_malloc_ab(size_t nmemb, size_t size)
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{
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if (size != 0 && nmemb > SIZE_MAX / size)
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return NULL;
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if (size * nmemb <= PAGE_SIZE)
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return kmalloc(nmemb * size, GFP_KERNEL);
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return __vmalloc(size * nmemb,
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GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL);
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}
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static __inline void drm_free_large(void *ptr)
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{
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if (!is_vmalloc_addr(ptr))
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return kfree(ptr);
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vfree(ptr);
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}
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#endif
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