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Diffstat (limited to 'drivers/md/raid6.h')
| -rw-r--r-- | drivers/md/raid6.h | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/drivers/md/raid6.h b/drivers/md/raid6.h new file mode 100644 index 00000000000..f80ee6350ed --- /dev/null +++ b/drivers/md/raid6.h @@ -0,0 +1,135 @@ +/* -*- linux-c -*- ------------------------------------------------------- * + * + * Copyright 2003 H. Peter Anvin - All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, Inc., 53 Temple Place Ste 330, + * Bostom MA 02111-1307, USA; either version 2 of the License, or + * (at your option) any later version; incorporated herein by reference. + * + * ----------------------------------------------------------------------- */ + +#ifndef LINUX_RAID_RAID6_H +#define LINUX_RAID_RAID6_H + +#ifdef __KERNEL__ + +/* Set to 1 to use kernel-wide empty_zero_page */ +#define RAID6_USE_EMPTY_ZERO_PAGE 0 + +#include <linux/module.h> +#include <linux/stddef.h> +#include <linux/compiler.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/mempool.h> +#include <linux/list.h> +#include <linux/vmalloc.h> +#include <linux/raid/md.h> +#include <linux/raid/raid5.h> + +typedef raid5_conf_t raid6_conf_t; /* Same configuration */ + +/* Additional compute_parity mode -- updates the parity w/o LOCKING */ +#define UPDATE_PARITY 4 + +/* We need a pre-zeroed page... if we don't want to use the kernel-provided + one define it here */ +#if RAID6_USE_EMPTY_ZERO_PAGE +# define raid6_empty_zero_page empty_zero_page +#else +extern const char raid6_empty_zero_page[PAGE_SIZE]; +#endif + +#else /* ! __KERNEL__ */ +/* Used for testing in user space */ + +#include <errno.h> +#include <inttypes.h> +#include <limits.h> +#include <stddef.h> +#include <sys/mman.h> +#include <sys/types.h> + +/* Not standard, but glibc defines it */ +#define BITS_PER_LONG __WORDSIZE + +typedef uint8_t u8; +typedef uint16_t u16; +typedef uint32_t u32; +typedef uint64_t u64; + +#ifndef PAGE_SIZE +# define PAGE_SIZE 4096 +#endif +extern const char raid6_empty_zero_page[PAGE_SIZE]; + +#define __init +#define __exit +#define __attribute_const__ __attribute__((const)) + +#define preempt_enable() +#define preempt_disable() + +#endif /* __KERNEL__ */ + +/* Routine choices */ +struct raid6_calls { + void (*gen_syndrome)(int, size_t, void **); + int (*valid)(void); /* Returns 1 if this routine set is usable */ + const char *name; /* Name of this routine set */ + int prefer; /* Has special performance attribute */ +}; + +/* Selected algorithm */ +extern struct raid6_calls raid6_call; + +/* Algorithm list */ +extern const struct raid6_calls * const raid6_algos[]; +int raid6_select_algo(void); + +/* Return values from chk_syndrome */ +#define RAID6_OK 0 +#define RAID6_P_BAD 1 +#define RAID6_Q_BAD 2 +#define RAID6_PQ_BAD 3 + +/* Galois field tables */ +extern const u8 raid6_gfmul[256][256] __attribute__((aligned(256))); +extern const u8 raid6_gfexp[256] __attribute__((aligned(256))); +extern const u8 raid6_gfinv[256] __attribute__((aligned(256))); +extern const u8 raid6_gfexi[256] __attribute__((aligned(256))); + +/* Recovery routines */ +void raid6_2data_recov(int disks, size_t bytes, int faila, int failb, void **ptrs); +void raid6_datap_recov(int disks, size_t bytes, int faila, void **ptrs); +void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, void **ptrs); + +/* Some definitions to allow code to be compiled for testing in userspace */ +#ifndef __KERNEL__ + +# define jiffies raid6_jiffies() +# define printk printf +# define GFP_KERNEL 0 +# define __get_free_pages(x,y) ((unsigned long)mmap(NULL, PAGE_SIZE << (y), PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, 0, 0)) +# define free_pages(x,y) munmap((void *)(x), (y)*PAGE_SIZE) + +static inline void cpu_relax(void) +{ + /* Nothing */ +} + +#undef HZ +#define HZ 1000 +static inline uint32_t raid6_jiffies(void) +{ + struct timeval tv; + gettimeofday(&tv, NULL); + return tv.tv_sec*1000 + tv.tv_usec/1000; +} + +#endif /* ! __KERNEL__ */ + +#endif /* LINUX_RAID_RAID6_H */ |