/*
   * Copyright (C) 2005, 2006

   * Avishay Traeger (avishay@gmail.com)

   * Copyright (C) 2008, 2009
   * Boaz Harrosh <bharrosh@panasas.com>
   *
   * Copyrights for code taken from ext2:
   *     Copyright (C) 1992, 1993, 1994, 1995
   *     Remy Card (card@masi.ibp.fr)
   *     Laboratoire MASI - Institut Blaise Pascal
   *     Universite Pierre et Marie Curie (Paris VI)
   *     from
   *     linux/fs/minix/inode.c
   *     Copyright (C) 1991, 1992  Linus Torvalds
   *
   * This file is part of exofs.
   *
   * exofs 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.  Since it is based on ext2, and the only
   * valid version of GPL for the Linux kernel is version 2, the only valid
   * version of GPL for exofs is version 2.
   *
   * exofs is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with exofs; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
   */

  #ifndef __EXOFS_H__
  #define __EXOFS_H__

  
  #include <linux/fs.h>
  #include <linux/time.h>

  #include <linux/backing-dev.h>

  #include "common.h"

  /* FIXME: Remove once pnfs hits mainline
   * #include <linux/exportfs/pnfs_osd_xdr.h>
   */
  #include "pnfs.h"

  #define EXOFS_ERR(fmt, a...) printk(KERN_ERR "exofs: " fmt, ##a)
  
  #ifdef CONFIG_EXOFS_DEBUG
  #define EXOFS_DBGMSG(fmt, a...) \
  	printk(KERN_NOTICE "exofs @%s:%d: " fmt, __func__, __LINE__, ##a)
  #else
  #define EXOFS_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)

  struct exofs_layout {
  	osd_id		s_pid;			/* partition ID of file system*/

  	/* Our way of looking at the data_map */
  	unsigned stripe_unit;
  	unsigned mirrors_p1;
  
  	unsigned group_width;

  	u64	 group_depth;
  	unsigned group_count;

  
  	enum exofs_inode_layout_gen_functions lay_func;

  	unsigned	s_numdevs;		/* Num of devices in array    */
  	struct osd_dev	*s_ods[0];		/* Variable length            */
  };

  /*
   * our extension to the in-memory superblock
   */
  struct exofs_sb_info {

  	struct exofs_fscb s_fscb;		/* Written often, pre-allocate*/

  	int		s_timeout;		/* timeout for OSD operations */
  	uint64_t	s_nextid;		/* highest object ID used     */
  	uint32_t	s_numfiles;		/* number of files on fs      */
  	spinlock_t	s_next_gen_lock;	/* spinlock for gen # update  */
  	u32		s_next_generation;	/* next gen # to use          */
  	atomic_t	s_curr_pending;		/* number of pending commands */

  	uint8_t		s_cred[OSD_CAP_LEN];	/* credential for the fscb    */

  	struct 		backing_dev_info bdi;	/* register our bdi with VFS  */

  	struct pnfs_osd_data_map data_map;	/* Default raid to use
  						 * FIXME: Needed ?
  						 */
  /*	struct exofs_layout	dir_layout;*/	/* Default dir layout */
  	struct exofs_layout	layout;		/* Default files layout,
  						 * contains the variable osd_dev
  						 * array. Keep last */
  	struct osd_dev	*_min_one_dev[1];	/* Place holder for one dev   */

  };
  
  /*
   * our extension to the in-memory inode
   */
  struct exofs_i_info {

  	struct inode   vfs_inode;          /* normal in-memory inode          */
  	wait_queue_head_t i_wq;            /* wait queue for inode            */

  	unsigned long  i_flags;            /* various atomic flags            */
  	uint32_t       i_data[EXOFS_IDATA];/*short symlink names and device #s*/
  	uint32_t       i_dir_start_lookup; /* which page to start lookup      */

  	uint64_t       i_commit_size;      /* the object's written length     */
  	uint8_t        i_cred[OSD_CAP_LEN];/* all-powerful credential         */

  };

  static inline osd_id exofs_oi_objno(struct exofs_i_info *oi)
  {
  	return oi->vfs_inode.i_ino + EXOFS_OBJ_OFF;
  }
  
  struct exofs_io_state;
  typedef void (*exofs_io_done_fn)(struct exofs_io_state *or, void *private);
  
  struct exofs_io_state {
  	struct kref		kref;
  
  	void			*private;
  	exofs_io_done_fn	done;

  	struct exofs_layout	*layout;

  	struct osd_obj_id	obj;
  	u8			*cred;
  
  	/* Global read/write IO*/
  	loff_t			offset;
  	unsigned long		length;
  	void			*kern_buff;

  
  	struct page		**pages;
  	unsigned		nr_pages;
  	unsigned		pgbase;

  	unsigned		pages_consumed;

  
  	/* Attributes */
  	unsigned		in_attr_len;
  	struct osd_attr 	*in_attr;
  	unsigned		out_attr_len;
  	struct osd_attr 	*out_attr;
  
  	/* Variable array of size numdevs */
  	unsigned numdevs;
  	struct exofs_per_dev_state {
  		struct osd_request *or;
  		struct bio *bio;

  		loff_t offset;
  		unsigned length;
  		unsigned dev;

  	} per_dev[];
  };
  
  static inline unsigned exofs_io_state_size(unsigned numdevs)
  {
  	return sizeof(struct exofs_io_state) +
  		sizeof(struct exofs_per_dev_state) * numdevs;
  }

  /*
   * our inode flags
   */
  #define OBJ_2BCREATED	0	/* object will be created soon*/
  #define OBJ_CREATED	1	/* object has been created on the osd*/
  
  static inline int obj_2bcreated(struct exofs_i_info *oi)
  {
  	return test_bit(OBJ_2BCREATED, &oi->i_flags);
  }
  
  static inline void set_obj_2bcreated(struct exofs_i_info *oi)
  {
  	set_bit(OBJ_2BCREATED, &oi->i_flags);
  }
  
  static inline int obj_created(struct exofs_i_info *oi)
  {
  	return test_bit(OBJ_CREATED, &oi->i_flags);
  }
  
  static inline void set_obj_created(struct exofs_i_info *oi)
  {
  	set_bit(OBJ_CREATED, &oi->i_flags);
  }
  
  int __exofs_wait_obj_created(struct exofs_i_info *oi);
  static inline int wait_obj_created(struct exofs_i_info *oi)
  {
  	if (likely(obj_created(oi)))
  		return 0;
  
  	return __exofs_wait_obj_created(oi);
  }
  
  /*
   * get to our inode from the vfs inode
   */
  static inline struct exofs_i_info *exofs_i(struct inode *inode)
  {
  	return container_of(inode, struct exofs_i_info, vfs_inode);
  }

  /*

   * Given a layout, object_number and stripe_index return the associated global
   * dev_index
   */
  unsigned exofs_layout_od_id(struct exofs_layout *layout,
  			    osd_id obj_no, unsigned layout_index);
  /*

   * Maximum count of links to a file
   */
  #define EXOFS_LINK_MAX           32000

  /*************************
   * function declarations *
   *************************/

  
  /* ios.c */
  void exofs_make_credential(u8 cred_a[OSD_CAP_LEN],
  			   const struct osd_obj_id *obj);
  int exofs_read_kern(struct osd_dev *od, u8 *cred, struct osd_obj_id *obj,
  		    u64 offset, void *p, unsigned length);

  int  exofs_get_io_state(struct exofs_layout *layout,
  			struct exofs_io_state **ios);

  void exofs_put_io_state(struct exofs_io_state *ios);
  
  int exofs_check_io(struct exofs_io_state *ios, u64 *resid);
  
  int exofs_sbi_create(struct exofs_io_state *ios);
  int exofs_sbi_remove(struct exofs_io_state *ios);
  int exofs_sbi_write(struct exofs_io_state *ios);
  int exofs_sbi_read(struct exofs_io_state *ios);
  
  int extract_attr_from_ios(struct exofs_io_state *ios, struct osd_attr *attr);
  
  int exofs_oi_truncate(struct exofs_i_info *oi, u64 new_len);
  static inline int exofs_oi_write(struct exofs_i_info *oi,
  				 struct exofs_io_state *ios)
  {
  	ios->obj.id = exofs_oi_objno(oi);
  	ios->cred = oi->i_cred;
  	return exofs_sbi_write(ios);
  }
  
  static inline int exofs_oi_read(struct exofs_i_info *oi,
  				struct exofs_io_state *ios)
  {
  	ios->obj.id = exofs_oi_objno(oi);
  	ios->cred = oi->i_cred;
  	return exofs_sbi_read(ios);
  }

  /* inode.c               */
  void exofs_truncate(struct inode *inode);
  int exofs_setattr(struct dentry *, struct iattr *);

  int exofs_write_begin(struct file *file, struct address_space *mapping,
  		loff_t pos, unsigned len, unsigned flags,
  		struct page **pagep, void **fsdata);

  extern struct inode *exofs_iget(struct super_block *, unsigned long);
  struct inode *exofs_new_inode(struct inode *, int);

  extern int exofs_write_inode(struct inode *, struct writeback_control *wbc);

  extern void exofs_delete_inode(struct inode *);

  
  /* dir.c:                */
  int exofs_add_link(struct dentry *, struct inode *);
  ino_t exofs_inode_by_name(struct inode *, struct dentry *);
  int exofs_delete_entry(struct exofs_dir_entry *, struct page *);
  int exofs_make_empty(struct inode *, struct inode *);
  struct exofs_dir_entry *exofs_find_entry(struct inode *, struct dentry *,
  					 struct page **);
  int exofs_empty_dir(struct inode *);
  struct exofs_dir_entry *exofs_dotdot(struct inode *, struct page **);

  ino_t exofs_parent_ino(struct dentry *child);

  int exofs_set_link(struct inode *, struct exofs_dir_entry *, struct page *,
  		    struct inode *);

  /* super.c               */
  int exofs_sync_fs(struct super_block *sb, int wait);

  /*********************
   * operation vectors *
   *********************/

  /* dir.c:            */
  extern const struct file_operations exofs_dir_operations;

  /* file.c            */
  extern const struct inode_operations exofs_file_inode_operations;
  extern const struct file_operations exofs_file_operations;

  /* inode.c           */
  extern const struct address_space_operations exofs_aops;

  extern const struct osd_attr g_attr_logical_length;

  /* namei.c           */
  extern const struct inode_operations exofs_dir_inode_operations;
  extern const struct inode_operations exofs_special_inode_operations;

  /* symlink.c         */
  extern const struct inode_operations exofs_symlink_inode_operations;
  extern const struct inode_operations exofs_fast_symlink_inode_operations;

  #endif