/*

   * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
   * 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.
   *

   * This program is distributed in the hope that it would 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 this program; if not, write the Free Software Foundation,
   * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

   */
  #ifndef __XFS_TRANS_PRIV_H__
  #define	__XFS_TRANS_PRIV_H__
  
  struct xfs_log_item;
  struct xfs_log_item_desc;
  struct xfs_mount;
  struct xfs_trans;

  struct xfs_ail;
  struct xfs_log_vec;

  void	xfs_trans_add_item(struct xfs_trans *, struct xfs_log_item *);
  void	xfs_trans_del_item(struct xfs_log_item *);

  void	xfs_trans_free_items(struct xfs_trans *tp, xfs_lsn_t commit_lsn,
  				int flags);

  void	xfs_trans_unreserve_and_mod_sb(struct xfs_trans *tp);

  void	xfs_trans_committed_bulk(struct xfs_ail *ailp, struct xfs_log_vec *lv,
  				xfs_lsn_t commit_lsn, int aborted);

  /*

   * AIL traversal cursor.
   *
   * Rather than using a generation number for detecting changes in the ail, use
   * a cursor that is protected by the ail lock. The aild cursor exists in the
   * struct xfs_ail, but other traversals can declare it on the stack and link it
   * to the ail list.
   *
   * When an object is deleted from or moved int the AIL, the cursor list is
   * searched to see if the object is a designated cursor item. If it is, it is
   * deleted from the cursor so that the next time the cursor is used traversal
   * will return to the start.
   *
   * This means a traversal colliding with a removal will cause a restart of the
   * list scan, rather than any insertion or deletion anywhere in the list. The
   * low bit of the item pointer is set if the cursor has been invalidated so
   * that we can tell the difference between invalidation and reaching the end
   * of the list to trigger traversal restarts.

   */

  struct xfs_ail_cursor {

  	struct list_head	list;

  	struct xfs_log_item	*item;
  };

  /*

   * Private AIL structures.
   *
   * Eventually we need to drive the locking in here as well.

   */

  struct xfs_ail {
  	struct xfs_mount	*xa_mount;

  	struct task_struct	*xa_task;

  	struct list_head	xa_ail;

  	xfs_lsn_t		xa_target;

  	struct list_head	xa_cursors;

  	spinlock_t		xa_lock;

  	xfs_lsn_t		xa_last_pushed_lsn;

  	int			xa_log_flush;

  };

  /*
   * From xfs_trans_ail.c
   */

  void	xfs_trans_ail_update_bulk(struct xfs_ail *ailp,

  				struct xfs_ail_cursor *cur,

  				struct xfs_log_item **log_items, int nr_items,
  				xfs_lsn_t lsn) __releases(ailp->xa_lock);
  static inline void
  xfs_trans_ail_update(
  	struct xfs_ail		*ailp,
  	struct xfs_log_item	*lip,
  	xfs_lsn_t		lsn) __releases(ailp->xa_lock)
  {

  	xfs_trans_ail_update_bulk(ailp, NULL, &lip, 1, lsn);

  }

  void	xfs_trans_ail_delete_bulk(struct xfs_ail *ailp,
  				struct xfs_log_item **log_items, int nr_items)
  				__releases(ailp->xa_lock);
  static inline void
  xfs_trans_ail_delete(
  	struct xfs_ail	*ailp,
  	xfs_log_item_t	*lip) __releases(ailp->xa_lock)
  {
  	xfs_trans_ail_delete_bulk(ailp, &lip, 1);
  }

  void			xfs_ail_push(struct xfs_ail *, xfs_lsn_t);
  void			xfs_ail_push_all(struct xfs_ail *);
  xfs_lsn_t		xfs_ail_min_lsn(struct xfs_ail *ailp);

  void			xfs_trans_unlocked_item(struct xfs_ail *,
  					xfs_log_item_t *);

  struct xfs_log_item *	xfs_trans_ail_cursor_first(struct xfs_ail *ailp,

  					struct xfs_ail_cursor *cur,
  					xfs_lsn_t lsn);

  struct xfs_log_item *	xfs_trans_ail_cursor_last(struct xfs_ail *ailp,
  					struct xfs_ail_cursor *cur,
  					xfs_lsn_t lsn);
  struct xfs_log_item *	xfs_trans_ail_cursor_next(struct xfs_ail *ailp,

  					struct xfs_ail_cursor *cur);

  void			xfs_trans_ail_cursor_done(struct xfs_ail *ailp,

  					struct xfs_ail_cursor *cur);

  #if BITS_PER_LONG != 64
  static inline void
  xfs_trans_ail_copy_lsn(
  	struct xfs_ail	*ailp,
  	xfs_lsn_t	*dst,
  	xfs_lsn_t	*src)
  {
  	ASSERT(sizeof(xfs_lsn_t) == 8);	/* don't lock if it shrinks */

  	spin_lock(&ailp->xa_lock);

  	*dst = *src;

  	spin_unlock(&ailp->xa_lock);

  }
  #else
  static inline void
  xfs_trans_ail_copy_lsn(
  	struct xfs_ail	*ailp,
  	xfs_lsn_t	*dst,
  	xfs_lsn_t	*src)
  {
  	ASSERT(sizeof(xfs_lsn_t) == 8);
  	*dst = *src;
  }
  #endif

  #endif	/* __XFS_TRANS_PRIV_H__ */