/*

   * Copyright (c) 2000-2001,2005 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

   */

  #include "xfs.h"

  #include "xfs_fs.h"

  #include "xfs_types.h"

  #include "xfs_bit.h"

  #include "xfs_log.h"

  #include "xfs_inum.h"

  #include "xfs_trans.h"
  #include "xfs_sb.h"
  #include "xfs_ag.h"

  #include "xfs_mount.h"

  #include "xfs_bmap_btree.h"

  #include "xfs_alloc_btree.h"

  #include "xfs_ialloc_btree.h"

  #include "xfs_dinode.h"
  #include "xfs_inode.h"

  #include "xfs_btree.h"
  #include "xfs_ialloc.h"
  #include "xfs_alloc.h"
  #include "xfs_error.h"

  STATIC int
  xfs_inobt_get_minrecs(
  	struct xfs_btree_cur	*cur,
  	int			level)
  {
  	return cur->bc_mp->m_inobt_mnr[level != 0];
  }

  STATIC struct xfs_btree_cur *
  xfs_inobt_dup_cursor(
  	struct xfs_btree_cur	*cur)
  {
  	return xfs_inobt_init_cursor(cur->bc_mp, cur->bc_tp,
  			cur->bc_private.a.agbp, cur->bc_private.a.agno);
  }

  STATIC void
  xfs_inobt_set_root(
  	struct xfs_btree_cur	*cur,
  	union xfs_btree_ptr	*nptr,
  	int			inc)	/* level change */
  {
  	struct xfs_buf		*agbp = cur->bc_private.a.agbp;
  	struct xfs_agi		*agi = XFS_BUF_TO_AGI(agbp);
  
  	agi->agi_root = nptr->s;
  	be32_add_cpu(&agi->agi_level, inc);
  	xfs_ialloc_log_agi(cur->bc_tp, agbp, XFS_AGI_ROOT | XFS_AGI_LEVEL);
  }

  STATIC int

  xfs_inobt_alloc_block(
  	struct xfs_btree_cur	*cur,
  	union xfs_btree_ptr	*start,
  	union xfs_btree_ptr	*new,
  	int			length,
  	int			*stat)
  {
  	xfs_alloc_arg_t		args;		/* block allocation args */
  	int			error;		/* error return value */
  	xfs_agblock_t		sbno = be32_to_cpu(start->s);
  
  	XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
  
  	memset(&args, 0, sizeof(args));
  	args.tp = cur->bc_tp;
  	args.mp = cur->bc_mp;
  	args.fsbno = XFS_AGB_TO_FSB(args.mp, cur->bc_private.a.agno, sbno);
  	args.minlen = 1;
  	args.maxlen = 1;
  	args.prod = 1;
  	args.type = XFS_ALLOCTYPE_NEAR_BNO;
  
  	error = xfs_alloc_vextent(&args);
  	if (error) {
  		XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
  		return error;
  	}
  	if (args.fsbno == NULLFSBLOCK) {
  		XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
  		*stat = 0;
  		return 0;
  	}
  	ASSERT(args.len == 1);
  	XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
  
  	new->s = cpu_to_be32(XFS_FSB_TO_AGBNO(args.mp, args.fsbno));
  	*stat = 1;
  	return 0;
  }

  STATIC int
  xfs_inobt_free_block(
  	struct xfs_btree_cur	*cur,
  	struct xfs_buf		*bp)
  {
  	xfs_fsblock_t		fsbno;
  	int			error;
  
  	fsbno = XFS_DADDR_TO_FSB(cur->bc_mp, XFS_BUF_ADDR(bp));
  	error = xfs_free_extent(cur->bc_tp, fsbno, 1);
  	if (error)
  		return error;
  
  	xfs_trans_binval(cur->bc_tp, bp);
  	return error;
  }

  
  STATIC int

  xfs_inobt_get_maxrecs(
  	struct xfs_btree_cur	*cur,
  	int			level)
  {
  	return cur->bc_mp->m_inobt_mxr[level != 0];
  }

  STATIC void
  xfs_inobt_init_key_from_rec(
  	union xfs_btree_key	*key,
  	union xfs_btree_rec	*rec)
  {
  	key->inobt.ir_startino = rec->inobt.ir_startino;
  }

  STATIC void
  xfs_inobt_init_rec_from_key(
  	union xfs_btree_key	*key,
  	union xfs_btree_rec	*rec)
  {
  	rec->inobt.ir_startino = key->inobt.ir_startino;
  }
  
  STATIC void
  xfs_inobt_init_rec_from_cur(
  	struct xfs_btree_cur	*cur,
  	union xfs_btree_rec	*rec)
  {
  	rec->inobt.ir_startino = cpu_to_be32(cur->bc_rec.i.ir_startino);
  	rec->inobt.ir_freecount = cpu_to_be32(cur->bc_rec.i.ir_freecount);
  	rec->inobt.ir_free = cpu_to_be64(cur->bc_rec.i.ir_free);
  }

  /*

   * initial value of ptr for lookup

   */
  STATIC void
  xfs_inobt_init_ptr_from_cur(
  	struct xfs_btree_cur	*cur,
  	union xfs_btree_ptr	*ptr)
  {
  	struct xfs_agi		*agi = XFS_BUF_TO_AGI(cur->bc_private.a.agbp);
  
  	ASSERT(cur->bc_private.a.agno == be32_to_cpu(agi->agi_seqno));
  
  	ptr->s = agi->agi_root;
  }
  
  STATIC __int64_t
  xfs_inobt_key_diff(
  	struct xfs_btree_cur	*cur,
  	union xfs_btree_key	*key)
  {
  	return (__int64_t)be32_to_cpu(key->inobt.ir_startino) -
  			  cur->bc_rec.i.ir_startino;
  }

  #ifdef DEBUG
  STATIC int
  xfs_inobt_keys_inorder(
  	struct xfs_btree_cur	*cur,
  	union xfs_btree_key	*k1,
  	union xfs_btree_key	*k2)
  {
  	return be32_to_cpu(k1->inobt.ir_startino) <
  		be32_to_cpu(k2->inobt.ir_startino);
  }
  
  STATIC int
  xfs_inobt_recs_inorder(
  	struct xfs_btree_cur	*cur,
  	union xfs_btree_rec	*r1,
  	union xfs_btree_rec	*r2)
  {
  	return be32_to_cpu(r1->inobt.ir_startino) + XFS_INODES_PER_CHUNK <=
  		be32_to_cpu(r2->inobt.ir_startino);
  }
  #endif	/* DEBUG */

  static const struct xfs_btree_ops xfs_inobt_ops = {

  	.rec_len		= sizeof(xfs_inobt_rec_t),
  	.key_len		= sizeof(xfs_inobt_key_t),

  	.dup_cursor		= xfs_inobt_dup_cursor,

  	.set_root		= xfs_inobt_set_root,

  	.alloc_block		= xfs_inobt_alloc_block,

  	.free_block		= xfs_inobt_free_block,

  	.get_minrecs		= xfs_inobt_get_minrecs,

  	.get_maxrecs		= xfs_inobt_get_maxrecs,

  	.init_key_from_rec	= xfs_inobt_init_key_from_rec,

  	.init_rec_from_key	= xfs_inobt_init_rec_from_key,
  	.init_rec_from_cur	= xfs_inobt_init_rec_from_cur,

  	.init_ptr_from_cur	= xfs_inobt_init_ptr_from_cur,
  	.key_diff		= xfs_inobt_key_diff,

  #ifdef DEBUG
  	.keys_inorder		= xfs_inobt_keys_inorder,
  	.recs_inorder		= xfs_inobt_recs_inorder,
  #endif

  };
  
  /*
   * Allocate a new inode btree cursor.
   */
  struct xfs_btree_cur *				/* new inode btree cursor */
  xfs_inobt_init_cursor(
  	struct xfs_mount	*mp,		/* file system mount point */
  	struct xfs_trans	*tp,		/* transaction pointer */
  	struct xfs_buf		*agbp,		/* buffer for agi structure */
  	xfs_agnumber_t		agno)		/* allocation group number */
  {
  	struct xfs_agi		*agi = XFS_BUF_TO_AGI(agbp);
  	struct xfs_btree_cur	*cur;
  
  	cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
  
  	cur->bc_tp = tp;
  	cur->bc_mp = mp;
  	cur->bc_nlevels = be32_to_cpu(agi->agi_level);
  	cur->bc_btnum = XFS_BTNUM_INO;
  	cur->bc_blocklog = mp->m_sb.sb_blocklog;
  
  	cur->bc_ops = &xfs_inobt_ops;
  
  	cur->bc_private.a.agbp = agbp;
  	cur->bc_private.a.agno = agno;
  
  	return cur;
  }

  
  /*
   * Calculate number of records in an inobt btree block.
   */
  int
  xfs_inobt_maxrecs(
  	struct xfs_mount	*mp,
  	int			blocklen,
  	int			leaf)
  {

  	blocklen -= XFS_INOBT_BLOCK_LEN(mp);

  
  	if (leaf)
  		return blocklen / sizeof(xfs_inobt_rec_t);
  	return blocklen / (sizeof(xfs_inobt_key_t) + sizeof(xfs_inobt_ptr_t));
  }