text: /*
   * Copyright (c) 2000,2005 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_IALLOC_H__
  #define	__XFS_IALLOC_H__
  
  struct xfs_buf;
  struct xfs_dinode;
  struct xfs_imap;
  struct xfs_mount;
  struct xfs_trans;
  struct xfs_btree_cur;
  
  /* Move inodes in clusters of this size */
  #define	XFS_INODE_BIG_CLUSTER_SIZE	8192
  
  struct xfs_icluster {
  	bool		deleted;	/* record is deleted */
  	xfs_ino_t	first_ino;	/* first inode number */
  	uint64_t	alloc;		/* inode phys. allocation bitmap for
  					 * sparse chunks */
  };
  
  /* Calculate and return the number of filesystem blocks per inode cluster */
  static inline int
  xfs_icluster_size_fsb(
  	struct xfs_mount	*mp)
  {
  	if (mp->m_sb.sb_blocksize >= mp->m_inode_cluster_size)
  		return 1;
  	return mp->m_inode_cluster_size >> mp->m_sb.sb_blocklog;
  }
  
  /*
   * Make an inode pointer out of the buffer/offset.
   */
  static inline struct xfs_dinode *
  xfs_make_iptr(struct xfs_mount *mp, struct xfs_buf *b, int o)
  {
  	return xfs_buf_offset(b, o << (mp)->m_sb.sb_inodelog);
  }
  
  /*
   * Allocate an inode on disk.
   * Mode is used to tell whether the new inode will need space, and whether
   * it is a directory.
   *
   * To work within the constraint of one allocation per transaction,
   * xfs_dialloc() is designed to be called twice if it has to do an
   * allocation to make more free inodes.  If an inode is
   * available without an allocation, agbp would be set to the current
   * agbp and alloc_done set to false.
   * If an allocation needed to be done, agbp would be set to the
   * inode header of the allocation group and alloc_done set to true.
   * The caller should then commit the current transaction and allocate a new
   * transaction.  xfs_dialloc() should then be called again with
   * the agbp value returned from the previous call.
   *
   * Once we successfully pick an inode its number is returned and the
   * on-disk data structures are updated.  The inode itself is not read
   * in, since doing so would break ordering constraints with xfs_reclaim.
   *
   * *agbp should be set to NULL on the first call, *alloc_done set to FALSE.
   */
  int					/* error */
  xfs_dialloc(
  	struct xfs_trans *tp,		/* transaction pointer */
  	xfs_ino_t	parent,		/* parent inode (directory) */
  	umode_t		mode,		/* mode bits for new inode */
  	struct xfs_buf	**agbp,		/* buf for a.g. inode header */
  	xfs_ino_t	*inop);		/* inode number allocated */
  
  /*
   * Free disk inode.  Carefully avoids touching the incore inode, all
   * manipulations incore are the caller's responsibility.
   * The on-disk inode is not changed by this operation, only the
   * btree (free inode mask) is changed.
   */
  int					/* error */
  xfs_difree(
  	struct xfs_trans *tp,		/* transaction pointer */
  	xfs_ino_t	inode,		/* inode to be freed */
  	struct xfs_defer_ops *dfops,	/* extents to free */
  	struct xfs_icluster *ifree);	/* cluster info if deleted */
  
  /*
   * Return the location of the inode in imap, for mapping it into a buffer.
   */
  int
  xfs_imap(
  	struct xfs_mount *mp,		/* file system mount structure */
  	struct xfs_trans *tp,		/* transaction pointer */
  	xfs_ino_t	ino,		/* inode to locate */
  	struct xfs_imap	*imap,		/* location map structure */
  	uint		flags);		/* flags for inode btree lookup */
  
  /*
   * Compute and fill in value of m_in_maxlevels.
   */
  void
  xfs_ialloc_compute_maxlevels(
  	struct xfs_mount *mp);		/* file system mount structure */
  
  /*
   * Log specified fields for the ag hdr (inode section)
   */
  void
  xfs_ialloc_log_agi(
  	struct xfs_trans *tp,		/* transaction pointer */
  	struct xfs_buf	*bp,		/* allocation group header buffer */
  	int		fields);	/* bitmask of fields to log */
  
  /*
   * Read in the allocation group header (inode allocation section)
   */
  int					/* error */
  xfs_ialloc_read_agi(
  	struct xfs_mount *mp,		/* file system mount structure */
  	struct xfs_trans *tp,		/* transaction pointer */
  	xfs_agnumber_t	agno,		/* allocation group number */
  	struct xfs_buf	**bpp);		/* allocation group hdr buf */
  
  /*
   * Read in the allocation group header to initialise the per-ag data
   * in the mount structure
   */
  int
  xfs_ialloc_pagi_init(
  	struct xfs_mount *mp,		/* file system mount structure */
  	struct xfs_trans *tp,		/* transaction pointer */
          xfs_agnumber_t  agno);		/* allocation group number */
  
  /*
   * Lookup a record by ino in the btree given by cur.
   */
  int xfs_inobt_lookup(struct xfs_btree_cur *cur, xfs_agino_t ino,
  		xfs_lookup_t dir, int *stat);
  
  /*
   * Get the data from the pointed-to record.
   */
  int xfs_inobt_get_rec(struct xfs_btree_cur *cur,
  		xfs_inobt_rec_incore_t *rec, int *stat);
  
  /*
   * Inode chunk initialisation routine
   */
  int xfs_ialloc_inode_init(struct xfs_mount *mp, struct xfs_trans *tp,
  			  struct list_head *buffer_list, int icount,
  			  xfs_agnumber_t agno, xfs_agblock_t agbno,
  			  xfs_agblock_t length, unsigned int gen);
  
  int xfs_read_agi(struct xfs_mount *mp, struct xfs_trans *tp,
  		xfs_agnumber_t agno, struct xfs_buf **bpp);
  
  union xfs_btree_rec;
  void xfs_inobt_btrec_to_irec(struct xfs_mount *mp, union xfs_btree_rec *rec,
  		struct xfs_inobt_rec_incore *irec);
  
  int xfs_ialloc_cluster_alignment(struct xfs_mount *mp);
  void xfs_ialloc_agino_range(struct xfs_mount *mp, xfs_agnumber_t agno,
  		xfs_agino_t *first, xfs_agino_t *last);
  bool xfs_verify_agino(struct xfs_mount *mp, xfs_agnumber_t agno,
  		xfs_agino_t agino);
  bool xfs_verify_ino(struct xfs_mount *mp, xfs_ino_t ino);
  bool xfs_internal_inum(struct xfs_mount *mp, xfs_ino_t ino);
  bool xfs_verify_dir_ino(struct xfs_mount *mp, xfs_ino_t ino);
  
  #endif	/* __XFS_IALLOC_H__ */
  