/*
   * Copyright (C) from 2011
   * Boaz Harrosh <bharrosh@panasas.com>
   *
   * This file is part of the objects raid engine (ore).
   *
   * It is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as published
   * by the Free Software Foundation.
   *
   * You should have received a copy of the GNU General Public License
   * along with "ore". If not, write to the Free Software Foundation, Inc:
   *	"Free Software Foundation <info@fsf.org>"
   */
  
  #include <scsi/osd_ore.h>
  
  #define ORE_ERR(fmt, a...) printk(KERN_ERR "ore: " fmt, ##a)
  
  #ifdef CONFIG_EXOFS_DEBUG
  #define ORE_DBGMSG(fmt, a...) \
  	printk(KERN_NOTICE "ore @%s:%d: " fmt, __func__, __LINE__, ##a)
  #else
  #define ORE_DBGMSG(fmt, a...) \
  	do { if (0) printk(fmt, ##a); } while (0)
  #endif
  
  /* u64 has problems with printk this will cast it to unsigned long long */
  #define _LLU(x) (unsigned long long)(x)
  
  #define ORE_DBGMSG2(M...) do {} while (0)
  /* #define ORE_DBGMSG2 ORE_DBGMSG */
  
  /* Calculate the component order in a stripe. eg the logical data unit
   * address within the stripe of @dev given the @par_dev of this stripe.
   */
  static inline unsigned _dev_order(unsigned devs_in_group, unsigned mirrors_p1,
  				  unsigned par_dev, unsigned dev)
  {
  	unsigned first_dev = dev - dev % devs_in_group;
  
  	dev -= first_dev;
  	par_dev -= first_dev;
  
  	if (devs_in_group == par_dev) /* The raid 0 case */
  		return dev / mirrors_p1;
  	/* raid4/5/6 case */
  	return ((devs_in_group + dev - par_dev - mirrors_p1) % devs_in_group) /
  	       mirrors_p1;
  }
  
  /* ios_raid.c stuff needed by ios.c */
  int _ore_post_alloc_raid_stuff(struct ore_io_state *ios);
  void _ore_free_raid_stuff(struct ore_io_state *ios);
  
  void _ore_add_sg_seg(struct ore_per_dev_state *per_dev, unsigned cur_len,
  		 bool not_last);
  int _ore_add_parity_unit(struct ore_io_state *ios, struct ore_striping_info *si,
  		     struct ore_per_dev_state *per_dev, unsigned cur_len);

  void _ore_add_stripe_page(struct __stripe_pages_2d *sp2d,
  		       struct ore_striping_info *si, struct page *page);
  static inline void _add_stripe_page(struct __stripe_pages_2d *sp2d,
  				struct ore_striping_info *si, struct page *page)
  {
  	if (!sp2d) /* Inline the fast path */
  		return; /* Hay no raid stuff */
  	_ore_add_stripe_page(sp2d, si, page);
  }

  
  /* ios.c stuff needed by ios_raid.c */

  int  _ore_get_io_state(struct ore_layout *layout,
  			struct ore_components *oc, unsigned numdevs,
  			unsigned sgs_per_dev, unsigned num_par_pages,
  			struct ore_io_state **pios);

  int _ore_add_stripe_unit(struct ore_io_state *ios,  unsigned *cur_pg,
  		unsigned pgbase, struct page **pages,
  		struct ore_per_dev_state *per_dev, int cur_len);

  int _ore_read_mirror(struct ore_io_state *ios, unsigned cur_comp);
  int ore_io_execute(struct ore_io_state *ios);