LXR linux/include/linux/raid/pq.h

   1/* -*- linux-c -*- ------------------------------------------------------- *
   2 *
   3 *   Copyright 2003 H. Peter Anvin - All Rights Reserved
   4 *
   5 *   This program is free software; you can redistribute it and/or modify
   6 *   it under the terms of the GNU General Public License as published by
   7 *   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
   8 *   Boston MA 02111-1307, USA; either version 2 of the License, or
   9 *   (at your option) any later version; incorporated herein by reference.
  10 *
  11 * ----------------------------------------------------------------------- */
  12
  13#ifndef LINUX_RAID_RAID6_H
  14#define LINUX_RAID_RAID6_H
  15
  16#ifdef __KERNEL__
  17
  18/* Set to 1 to use kernel-wide empty_zero_page */
  19#define RAID6_USE_EMPTY_ZERO_PAGE 0
  20#include <linux/blkdev.h>
  21
  22/* We need a pre-zeroed page... if we don't want to use the kernel-provided
  23   one define it here */
  24#if RAID6_USE_EMPTY_ZERO_PAGE
  25# define raid6_empty_zero_page empty_zero_page
  26#else
  27extern const char raid6_empty_zero_page[PAGE_SIZE];
  28#endif
  29
  30#else /* ! __KERNEL__ */
  31/* Used for testing in user space */
  32
  33#include <errno.h>
  34#include <inttypes.h>
  35#include <limits.h>
  36#include <stddef.h>
  37#include <sys/mman.h>
  38#include <sys/types.h>
  39
  40/* Not standard, but glibc defines it */
  41#define BITS_PER_LONG __WORDSIZE
  42
  43typedef uint8_t  u8;
  44typedef uint16_t u16;
  45typedef uint32_t u32;
  46typedef uint64_t u64;
  47
  48#ifndef PAGE_SIZE
  49# define PAGE_SIZE 4096
  50#endif
  51extern const char raid6_empty_zero_page[PAGE_SIZE];
  52
  53#define __init
  54#define __exit
  55#define __attribute_const__ __attribute__((const))
  56#define noinline __attribute__((noinline))
  57
  58#define preempt_enable()
  59#define preempt_disable()
  60#define cpu_has_feature(x) 1
  61#define enable_kernel_altivec()
  62#define disable_kernel_altivec()
  63
  64#define EXPORT_SYMBOL(sym)
  65#define MODULE_LICENSE(licence)
  66#define subsys_initcall(x)
  67#define module_exit(x)
  68#endif /* __KERNEL__ */
  69
  70/* Routine choices */
  71struct raid6_calls {
  72        void (*gen_syndrome)(int, size_t, void **);
  73        int  (*valid)(void);    /* Returns 1 if this routine set is usable */
  74        const char *name;       /* Name of this routine set */
  75        int prefer;             /* Has special performance attribute */
  76};
  77
  78/* Selected algorithm */
  79extern struct raid6_calls raid6_call;
  80
  81/* Various routine sets */
  82extern const struct raid6_calls raid6_intx1;
  83extern const struct raid6_calls raid6_intx2;
  84extern const struct raid6_calls raid6_intx4;
  85extern const struct raid6_calls raid6_intx8;
  86extern const struct raid6_calls raid6_intx16;
  87extern const struct raid6_calls raid6_intx32;
  88extern const struct raid6_calls raid6_mmxx1;
  89extern const struct raid6_calls raid6_mmxx2;
  90extern const struct raid6_calls raid6_sse1x1;
  91extern const struct raid6_calls raid6_sse1x2;
  92extern const struct raid6_calls raid6_sse2x1;
  93extern const struct raid6_calls raid6_sse2x2;
  94extern const struct raid6_calls raid6_sse2x4;
  95extern const struct raid6_calls raid6_altivec1;
  96extern const struct raid6_calls raid6_altivec2;
  97extern const struct raid6_calls raid6_altivec4;
  98extern const struct raid6_calls raid6_altivec8;
  99
 100/* Algorithm list */
 101extern const struct raid6_calls * const raid6_algos[];
 102int raid6_select_algo(void);
 103
 104/* Return values from chk_syndrome */
 105#define RAID6_OK        0
 106#define RAID6_P_BAD     1
 107#define RAID6_Q_BAD     2
 108#define RAID6_PQ_BAD    3
 109
 110/* Galois field tables */
 111extern const u8 raid6_gfmul[256][256] __attribute__((aligned(256)));
 112extern const u8 raid6_gfexp[256]      __attribute__((aligned(256)));
 113extern const u8 raid6_gfinv[256]      __attribute__((aligned(256)));
 114extern const u8 raid6_gfexi[256]      __attribute__((aligned(256)));
 115
 116/* Recovery routines */
 117void raid6_2data_recov(int disks, size_t bytes, int faila, int failb,
 118                       void **ptrs);
 119void raid6_datap_recov(int disks, size_t bytes, int faila, void **ptrs);
 120void raid6_dual_recov(int disks, size_t bytes, int faila, int failb,
 121                      void **ptrs);
 122
 123/* Some definitions to allow code to be compiled for testing in userspace */
 124#ifndef __KERNEL__
 125
 126# define jiffies        raid6_jiffies()
 127# define printk         printf
 128# define GFP_KERNEL     0
 129# define __get_free_pages(x, y) ((unsigned long)mmap(NULL, PAGE_SIZE << (y), \
 130                                                     PROT_READ|PROT_WRITE,   \
 131                                                     MAP_PRIVATE|MAP_ANONYMOUS,\
 132                                                     0, 0))
 133# define free_pages(x, y)       munmap((void *)(x), (y)*PAGE_SIZE)
 134
 135static inline void cpu_relax(void)
 136{
 137        /* Nothing */
 138}
 139
 140#undef  HZ
 141#define HZ 1000
 142static inline uint32_t raid6_jiffies(void)
 143{
 144        struct timeval tv;
 145        gettimeofday(&tv, NULL);
 146        return tv.tv_sec*1000 + tv.tv_usec/1000;
 147}
 148
 149#endif /* ! __KERNEL__ */
 150
 151#endif /* LINUX_RAID_RAID6_H */
 152