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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* -*- 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 * Bostom 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
NeilBrownbff61972009-03-31 14:33:13 +110020#include <linux/blkdev.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021
22/* Additional compute_parity mode -- updates the parity w/o LOCKING */
23#define UPDATE_PARITY 4
24
25/* We need a pre-zeroed page... if we don't want to use the kernel-provided
26 one define it here */
27#if RAID6_USE_EMPTY_ZERO_PAGE
28# define raid6_empty_zero_page empty_zero_page
29#else
30extern const char raid6_empty_zero_page[PAGE_SIZE];
31#endif
32
33#else /* ! __KERNEL__ */
34/* Used for testing in user space */
35
36#include <errno.h>
37#include <inttypes.h>
38#include <limits.h>
39#include <stddef.h>
40#include <sys/mman.h>
41#include <sys/types.h>
42
43/* Not standard, but glibc defines it */
44#define BITS_PER_LONG __WORDSIZE
45
46typedef uint8_t u8;
47typedef uint16_t u16;
48typedef uint32_t u32;
49typedef uint64_t u64;
50
51#ifndef PAGE_SIZE
52# define PAGE_SIZE 4096
53#endif
54extern const char raid6_empty_zero_page[PAGE_SIZE];
55
56#define __init
57#define __exit
58#define __attribute_const__ __attribute__((const))
H. Peter Anvind7e70ba2005-09-16 19:27:29 -070059#define noinline __attribute__((noinline))
Linus Torvalds1da177e2005-04-16 15:20:36 -070060
61#define preempt_enable()
62#define preempt_disable()
H. Peter Anvind7e70ba2005-09-16 19:27:29 -070063#define cpu_has_feature(x) 1
64#define enable_kernel_altivec()
65#define disable_kernel_altivec()
Linus Torvalds1da177e2005-04-16 15:20:36 -070066
67#endif /* __KERNEL__ */
68
69/* Routine choices */
70struct raid6_calls {
71 void (*gen_syndrome)(int, size_t, void **);
72 int (*valid)(void); /* Returns 1 if this routine set is usable */
73 const char *name; /* Name of this routine set */
74 int prefer; /* Has special performance attribute */
75};
76
77/* Selected algorithm */
78extern struct raid6_calls raid6_call;
79
80/* Algorithm list */
81extern const struct raid6_calls * const raid6_algos[];
82int raid6_select_algo(void);
83
84/* Return values from chk_syndrome */
85#define RAID6_OK 0
86#define RAID6_P_BAD 1
87#define RAID6_Q_BAD 2
88#define RAID6_PQ_BAD 3
89
90/* Galois field tables */
91extern const u8 raid6_gfmul[256][256] __attribute__((aligned(256)));
92extern const u8 raid6_gfexp[256] __attribute__((aligned(256)));
93extern const u8 raid6_gfinv[256] __attribute__((aligned(256)));
94extern const u8 raid6_gfexi[256] __attribute__((aligned(256)));
95
96/* Recovery routines */
97void raid6_2data_recov(int disks, size_t bytes, int faila, int failb, void **ptrs);
98void raid6_datap_recov(int disks, size_t bytes, int faila, void **ptrs);
99void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, void **ptrs);
100
101/* Some definitions to allow code to be compiled for testing in userspace */
102#ifndef __KERNEL__
103
104# define jiffies raid6_jiffies()
105# define printk printf
106# define GFP_KERNEL 0
107# define __get_free_pages(x,y) ((unsigned long)mmap(NULL, PAGE_SIZE << (y), PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, 0, 0))
108# define free_pages(x,y) munmap((void *)(x), (y)*PAGE_SIZE)
109
110static inline void cpu_relax(void)
111{
112 /* Nothing */
113}
114
115#undef HZ
116#define HZ 1000
117static inline uint32_t raid6_jiffies(void)
118{
119 struct timeval tv;
120 gettimeofday(&tv, NULL);
121 return tv.tv_sec*1000 + tv.tv_usec/1000;
122}
123
124#endif /* ! __KERNEL__ */
125
126#endif /* LINUX_RAID_RAID6_H */