/* -*- 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,

   *   Boston 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/blkdev.h>

  /* 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 noinline __attribute__((noinline))

  
  #define preempt_enable()
  #define preempt_disable()

  #define cpu_has_feature(x) 1
  #define enable_kernel_altivec()
  #define disable_kernel_altivec()

  #define EXPORT_SYMBOL(sym)

  #define EXPORT_SYMBOL_GPL(sym)

  #define MODULE_LICENSE(licence)

  #define MODULE_DESCRIPTION(desc)

  #define subsys_initcall(x)
  #define module_exit(x)

  #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;

  /* Various routine sets */
  extern const struct raid6_calls raid6_intx1;
  extern const struct raid6_calls raid6_intx2;
  extern const struct raid6_calls raid6_intx4;
  extern const struct raid6_calls raid6_intx8;
  extern const struct raid6_calls raid6_intx16;
  extern const struct raid6_calls raid6_intx32;
  extern const struct raid6_calls raid6_mmxx1;
  extern const struct raid6_calls raid6_mmxx2;
  extern const struct raid6_calls raid6_sse1x1;
  extern const struct raid6_calls raid6_sse1x2;
  extern const struct raid6_calls raid6_sse2x1;
  extern const struct raid6_calls raid6_sse2x2;
  extern const struct raid6_calls raid6_sse2x4;
  extern const struct raid6_calls raid6_altivec1;
  extern const struct raid6_calls raid6_altivec2;
  extern const struct raid6_calls raid6_altivec4;
  extern const struct raid6_calls raid6_altivec8;

  /* 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 */