Module Name: src Committed By: riastradh Date: Sun Dec 19 12:20:21 UTC 2021
Added Files: src/sys/external/bsd/common/include/linux: overflow.h Removed Files: src/sys/external/bsd/drm2/include/linux: overflow.h Log Message: linux: Move linux/overflow.h from drm2 to common. Needed so linux/slab.h can side-load it. To generate a diff of this commit: cvs rdiff -u -r0 -r1.1 src/sys/external/bsd/common/include/linux/overflow.h cvs rdiff -u -r1.4 -r0 src/sys/external/bsd/drm2/include/linux/overflow.h Please note that diffs are not public domain; they are subject to the copyright notices on the relevant files.
Added files: Index: src/sys/external/bsd/common/include/linux/overflow.h diff -u /dev/null src/sys/external/bsd/common/include/linux/overflow.h:1.1 --- /dev/null Sun Dec 19 12:20:21 2021 +++ src/sys/external/bsd/common/include/linux/overflow.h Sun Dec 19 12:20:21 2021 @@ -0,0 +1,86 @@ +/* $NetBSD: overflow.h,v 1.1 2021/12/19 12:20:21 riastradh Exp $ */ + +/*- + * Copyright (c) 2018 The NetBSD Foundation, Inc. + * All rights reserved. + * + * This code is derived from software contributed to The NetBSD Foundation + * by Taylor R. Campbell. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED + * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef _LINUX_OVERFLOW_H_ +#define _LINUX_OVERFLOW_H_ + +#include <sys/types.h> + +#include <lib/libkern/libkern.h> /* offsetof */ + +#define check_mul_overflow(a, b, res) __builtin_mul_overflow(a, b, res) +#define check_add_overflow(a, b, res) __builtin_add_overflow(a, b, res) + +/* return x*y saturated at SIZE_MAX */ +static inline size_t +array_size(size_t x, size_t y) +{ + size_t xy; + + if (check_mul_overflow(x, y, &xy)) + return SIZE_MAX; + return xy; +} + +/* return x*y*z saturated at SIZE_MAX */ +static inline size_t +array3_size(size_t x, size_t y, size_t z) +{ + size_t xy, xyz; + + if (check_mul_overflow(x, y, &xy)) + return SIZE_MAX; + if (check_mul_overflow(xy, z, &xyz)) + return SIZE_MAX; + return xyz; +} + +/* return basesize + elemsize*nelem saturated at SIZE_MAX */ +static inline size_t +__struct_size(size_t basesize, size_t elemsize, size_t nelem) +{ + size_t arraysize, totalsize; + + KASSERT(elemsize); + if ((arraysize = array_size(elemsize, nelem)) == SIZE_MAX) + return SIZE_MAX; + if (check_add_overflow(basesize, arraysize, &totalsize)) + return SIZE_MAX; + return totalsize; +} + +#define struct_size(p, member, n) \ +({ \ + CTASSERT(sizeof(*(p)) == offsetof(__typeof__(*(p)), member)); \ + __struct_size(sizeof(*(p)), sizeof((p)->member[0]), (n)); \ +}) + +#endif /* _LINUX_OVERFLOW_H_ */