ref: 151cd9f6e9120e3c41600875c6cfa42dc1321a0b
dir: /include/ext4_misc.h/
/* * Copyright (c) 2015 Grzegorz Kostka (kostka.grzegorz@gmail.com) * Copyright (c) 2015 Kaho Ng (ngkaho1234@gmail.com) * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * - 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. * - The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. */ /** @addtogroup lwext4 * @{ */ /** * @file ext4_misc.h * @brief Miscellaneous helpers. */ #ifndef EXT4_MISC_H_ #define EXT4_MISC_H_ #ifdef __cplusplus extern "C" { #endif #include <stdint.h> /**************************************************************/ #define EXT4_DIV_ROUND_UP(x, y) (((x) + (y) - 1)/(y)) #define EXT4_ALIGN(x, y) ((y) * EXT4_DIV_ROUND_UP((x), (y))) /****************************Endian conversion*****************/ static inline uint64_t reorder64(uint64_t n) { return ((n & 0xff) << 56) | ((n & 0xff00) << 40) | ((n & 0xff0000) << 24) | ((n & 0xff000000LL) << 8) | ((n & 0xff00000000LL) >> 8) | ((n & 0xff0000000000LL) >> 24) | ((n & 0xff000000000000LL) >> 40) | ((n & 0xff00000000000000LL) >> 56); } static inline uint32_t reorder32(uint32_t n) { return ((n & 0xff) << 24) | ((n & 0xff00) << 8) | ((n & 0xff0000) >> 8) | ((n & 0xff000000) >> 24); } static inline uint16_t reorder16(uint16_t n) { return ((n & 0xff) << 8) | ((n & 0xff00) >> 8); } #ifdef CONFIG_BIG_ENDIAN #define to_le64(_n) reorder64(_n) #define to_le32(_n) reorder32(_n) #define to_le16(_n) reorder16(_n) #define to_be64(_n) _n #define to_be32(_n) _n #define to_be16(_n) _n #else #define to_le64(_n) _n #define to_le32(_n) _n #define to_le16(_n) _n #define to_be64(_n) reorder64(_n) #define to_be32(_n) reorder32(_n) #define to_be16(_n) reorder16(_n) #endif /****************************Access macros to ext4 structures*****************/ #define ext4_get32(s, f) to_le32((s)->f) #define ext4_get16(s, f) to_le16((s)->f) #define ext4_get8(s, f) (s)->f #define ext4_set32(s, f, v) \ do { \ (s)->f = to_le32(v); \ } while (0) #define ext4_set16(s, f, v) \ do { \ (s)->f = to_le16(v); \ } while (0) #define ext4_set8 \ (s, f, v) do { (s)->f = (v); } \ while (0) /****************************Access macros to jbd2 structures*****************/ #define jbd_get32(s, f) to_be32((s)->f) #define jbd_get16(s, f) to_be16((s)->f) #define jbd_get8(s, f) (s)->f #define jbd_set32(s, f, v) \ do { \ (s)->f = to_be32(v); \ } while (0) #define jbd_set16(s, f, v) \ do { \ (s)->f = to_be16(v); \ } while (0) #define jbd_set8 \ (s, f, v) do { (s)->f = (v); } \ while (0) #ifdef __GNUC__ #ifndef __unused #define __unused __attribute__ ((__unused__)) #endif #else #define __unused #endif #ifndef offsetof #define offsetof(type, field) \ ((size_t)(&(((type *)0)->field))) #endif #ifdef __cplusplus } #endif #endif /* EXT4_MISC_H_ */ /** * @} */