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
   */
  #include "xfs.h"
  #include "xfs_fs.h"
  #include "xfs_shared.h"
  #include "xfs_format.h"
  #include "xfs_log_format.h"
  #include "xfs_trans_resv.h"
  #include "xfs_bit.h"
  #include "xfs_sb.h"
  #include "xfs_ag.h"
  #include "xfs_mount.h"
  #include "xfs_da_format.h"
  #include "xfs_da_btree.h"
  #include "xfs_attr_sf.h"
  #include "xfs_inode.h"
  #include "xfs_alloc.h"
  #include "xfs_trans.h"
  #include "xfs_inode_item.h"
  #include "xfs_bmap.h"
  #include "xfs_bmap_util.h"
  #include "xfs_bmap_btree.h"
  #include "xfs_attr.h"
  #include "xfs_attr_leaf.h"
  #include "xfs_attr_remote.h"
  #include "xfs_error.h"
  #include "xfs_quota.h"
  #include "xfs_trans_space.h"
  #include "xfs_trace.h"
  #include "xfs_dinode.h"
  
  /*
   * xfs_attr.c
   *
   * Provide the external interfaces to manage attribute lists.
   */
  
  /*========================================================================
   * Function prototypes for the kernel.
   *========================================================================*/
  
  /*
   * Internal routines when attribute list fits inside the inode.
   */
  STATIC int xfs_attr_shortform_addname(xfs_da_args_t *args);
  
  /*
   * Internal routines when attribute list is one block.
   */
  STATIC int xfs_attr_leaf_get(xfs_da_args_t *args);
  STATIC int xfs_attr_leaf_addname(xfs_da_args_t *args);
  STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
  
  /*
   * Internal routines when attribute list is more than one block.
   */
  STATIC int xfs_attr_node_get(xfs_da_args_t *args);
  STATIC int xfs_attr_node_addname(xfs_da_args_t *args);
  STATIC int xfs_attr_node_removename(xfs_da_args_t *args);
  STATIC int xfs_attr_fillstate(xfs_da_state_t *state);
  STATIC int xfs_attr_refillstate(xfs_da_state_t *state);
  
  
  STATIC int
  xfs_attr_args_init(
  	struct xfs_da_args	*args,
  	struct xfs_inode	*dp,
  	const unsigned char	*name,
  	int			flags)
  {
  
  	if (!name)
  		return -EINVAL;
  
  	memset(args, 0, sizeof(*args));
  	args->geo = dp->i_mount->m_attr_geo;
  	args->whichfork = XFS_ATTR_FORK;
  	args->dp = dp;
  	args->flags = flags;
  	args->name = name;
  	args->namelen = strlen((const char *)name);
  	if (args->namelen >= MAXNAMELEN)
  		return -EFAULT;		/* match IRIX behaviour */
  
  	args->hashval = xfs_da_hashname(args->name, args->namelen);
  	return 0;
  }
  
  int
  xfs_inode_hasattr(
  	struct xfs_inode	*ip)
  {
  	if (!XFS_IFORK_Q(ip) ||
  	    (ip->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS &&
  	     ip->i_d.di_anextents == 0))
  		return 0;
  	return 1;
  }
  
  /*========================================================================
   * Overall external interface routines.
   *========================================================================*/
  
  int
  xfs_attr_get(
  	struct xfs_inode	*ip,
  	const unsigned char	*name,
  	unsigned char		*value,
  	int			*valuelenp,
  	int			flags)
  {
  	struct xfs_da_args	args;
  	uint			lock_mode;
  	int			error;
  
  	XFS_STATS_INC(xs_attr_get);
  
  	if (XFS_FORCED_SHUTDOWN(ip->i_mount))
  		return -EIO;
  
  	if (!xfs_inode_hasattr(ip))
  		return -ENOATTR;
  
  	error = xfs_attr_args_init(&args, ip, name, flags);
  	if (error)
  		return error;
  
  	args.value = value;
  	args.valuelen = *valuelenp;
  
  	lock_mode = xfs_ilock_attr_map_shared(ip);
  	if (!xfs_inode_hasattr(ip))
  		error = -ENOATTR;
  	else if (ip->i_d.di_aformat == XFS_DINODE_FMT_LOCAL)
  		error = xfs_attr_shortform_getvalue(&args);
  	else if (xfs_bmap_one_block(ip, XFS_ATTR_FORK))
  		error = xfs_attr_leaf_get(&args);
  	else
  		error = xfs_attr_node_get(&args);
  	xfs_iunlock(ip, lock_mode);
  
  	*valuelenp = args.valuelen;
  	return error == -EEXIST ? 0 : error;
  }
  
  /*
   * Calculate how many blocks we need for the new attribute,
   */
  STATIC int
  xfs_attr_calc_size(
  	struct xfs_da_args	*args,
  	int			*local)
  {
  	struct xfs_mount	*mp = args->dp->i_mount;
  	int			size;
  	int			nblks;
  
  	/*
  	 * Determine space new attribute will use, and if it would be
  	 * "local" or "remote" (note: local != inline).
  	 */
  	size = xfs_attr_leaf_newentsize(args, local);
  	nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK);
  	if (*local) {
  		if (size > (args->geo->blksize / 2)) {
  			/* Double split possible */
  			nblks *= 2;
  		}
  	} else {
  		/*
  		 * Out of line attribute, cannot double split, but
  		 * make room for the attribute value itself.
  		 */
  		uint	dblocks = xfs_attr3_rmt_blocks(mp, args->valuelen);
  		nblks += dblocks;
  		nblks += XFS_NEXTENTADD_SPACE_RES(mp, dblocks, XFS_ATTR_FORK);
  	}
  
  	return nblks;
  }
  
  int
  xfs_attr_set(
  	struct xfs_inode	*dp,
  	const unsigned char	*name,
  	unsigned char		*value,
  	int			valuelen,
  	int			flags)
  {
  	struct xfs_mount	*mp = dp->i_mount;
  	struct xfs_da_args	args;
  	struct xfs_bmap_free	flist;
  	struct xfs_trans_res	tres;
  	xfs_fsblock_t		firstblock;
  	int			rsvd = (flags & ATTR_ROOT) != 0;
  	int			error, err2, committed, local;
  
  	XFS_STATS_INC(xs_attr_set);
  
  	if (XFS_FORCED_SHUTDOWN(dp->i_mount))
  		return -EIO;
  
  	error = xfs_attr_args_init(&args, dp, name, flags);
  	if (error)
  		return error;
  
  	args.value = value;
  	args.valuelen = valuelen;
  	args.firstblock = &firstblock;
  	args.flist = &flist;
  	args.op_flags = XFS_DA_OP_ADDNAME | XFS_DA_OP_OKNOENT;
  	args.total = xfs_attr_calc_size(&args, &local);
  
  	error = xfs_qm_dqattach(dp, 0);
  	if (error)
  		return error;
  
  	/*
  	 * If the inode doesn't have an attribute fork, add one.
  	 * (inode must not be locked when we call this routine)
  	 */
  	if (XFS_IFORK_Q(dp) == 0) {
  		int sf_size = sizeof(xfs_attr_sf_hdr_t) +
  			XFS_ATTR_SF_ENTSIZE_BYNAME(args.namelen, valuelen);
  
  		error = xfs_bmap_add_attrfork(dp, sf_size, rsvd);
  		if (error)
  			return error;
  	}
  
  	/*
  	 * Start our first transaction of the day.
  	 *
  	 * All future transactions during this code must be "chained" off
  	 * this one via the trans_dup() call.  All transactions will contain
  	 * the inode, and the inode will always be marked with trans_ihold().
  	 * Since the inode will be locked in all transactions, we must log
  	 * the inode in every transaction to let it float upward through
  	 * the log.
  	 */
  	args.trans = xfs_trans_alloc(mp, XFS_TRANS_ATTR_SET);
  
  	/*
  	 * Root fork attributes can use reserved data blocks for this
  	 * operation if necessary
  	 */
  
  	if (rsvd)
  		args.trans->t_flags |= XFS_TRANS_RESERVE;
  
  	tres.tr_logres = M_RES(mp)->tr_attrsetm.tr_logres +
  			 M_RES(mp)->tr_attrsetrt.tr_logres * args.total;
  	tres.tr_logcount = XFS_ATTRSET_LOG_COUNT;
  	tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
  	error = xfs_trans_reserve(args.trans, &tres, args.total, 0);
  	if (error) {
  		xfs_trans_cancel(args.trans, 0);
  		return error;
  	}
  	xfs_ilock(dp, XFS_ILOCK_EXCL);
  
  	error = xfs_trans_reserve_quota_nblks(args.trans, dp, args.total, 0,
  				rsvd ? XFS_QMOPT_RES_REGBLKS | XFS_QMOPT_FORCE_RES :
  				       XFS_QMOPT_RES_REGBLKS);
  	if (error) {
  		xfs_iunlock(dp, XFS_ILOCK_EXCL);
  		xfs_trans_cancel(args.trans, XFS_TRANS_RELEASE_LOG_RES);
  		return error;
  	}
  
  	xfs_trans_ijoin(args.trans, dp, 0);
  
  	/*
  	 * If the attribute list is non-existent or a shortform list,
  	 * upgrade it to a single-leaf-block attribute list.
  	 */
  	if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL ||
  	    (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS &&
  	     dp->i_d.di_anextents == 0)) {
  
  		/*
  		 * Build initial attribute list (if required).
  		 */
  		if (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS)
  			xfs_attr_shortform_create(&args);
  
  		/*
  		 * Try to add the attr to the attribute list in
  		 * the inode.
  		 */
  		error = xfs_attr_shortform_addname(&args);
  		if (error != -ENOSPC) {
  			/*
  			 * Commit the shortform mods, and we're done.
  			 * NOTE: this is also the error path (EEXIST, etc).
  			 */
  			ASSERT(args.trans != NULL);
  
  			/*
  			 * If this is a synchronous mount, make sure that
  			 * the transaction goes to disk before returning
  			 * to the user.
  			 */
  			if (mp->m_flags & XFS_MOUNT_WSYNC)
  				xfs_trans_set_sync(args.trans);
  
  			if (!error && (flags & ATTR_KERNOTIME) == 0) {
  				xfs_trans_ichgtime(args.trans, dp,
  							XFS_ICHGTIME_CHG);
  			}
  			err2 = xfs_trans_commit(args.trans,
  						 XFS_TRANS_RELEASE_LOG_RES);
  			xfs_iunlock(dp, XFS_ILOCK_EXCL);
  
  			return error ? error : err2;
  		}
  
  		/*
  		 * It won't fit in the shortform, transform to a leaf block.
  		 * GROT: another possible req'mt for a double-split btree op.
  		 */
  		xfs_bmap_init(args.flist, args.firstblock);
  		error = xfs_attr_shortform_to_leaf(&args);
  		if (!error) {
  			error = xfs_bmap_finish(&args.trans, args.flist,
  						&committed);
  		}
  		if (error) {
  			ASSERT(committed);
  			args.trans = NULL;
  			xfs_bmap_cancel(&flist);
  			goto out;
  		}
  
  		/*
  		 * bmap_finish() may have committed the last trans and started
  		 * a new one.  We need the inode to be in all transactions.
  		 */
  		if (committed)
  			xfs_trans_ijoin(args.trans, dp, 0);
  
  		/*
  		 * Commit the leaf transformation.  We'll need another (linked)
  		 * transaction to add the new attribute to the leaf.
  		 */
  
  		error = xfs_trans_roll(&args.trans, dp);
  		if (error)
  			goto out;
  
  	}
  
  	if (xfs_bmap_one_block(dp, XFS_ATTR_FORK))
  		error = xfs_attr_leaf_addname(&args);
  	else
  		error = xfs_attr_node_addname(&args);
  	if (error)
  		goto out;
  
  	/*
  	 * If this is a synchronous mount, make sure that the
  	 * transaction goes to disk before returning to the user.
  	 */
  	if (mp->m_flags & XFS_MOUNT_WSYNC)
  		xfs_trans_set_sync(args.trans);
  
  	if ((flags & ATTR_KERNOTIME) == 0)
  		xfs_trans_ichgtime(args.trans, dp, XFS_ICHGTIME_CHG);
  
  	/*
  	 * Commit the last in the sequence of transactions.
  	 */
  	xfs_trans_log_inode(args.trans, dp, XFS_ILOG_CORE);
  	error = xfs_trans_commit(args.trans, XFS_TRANS_RELEASE_LOG_RES);
  	xfs_iunlock(dp, XFS_ILOCK_EXCL);
  
  	return error;
  
  out:
  	if (args.trans) {
  		xfs_trans_cancel(args.trans,
  			XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
  	}
  	xfs_iunlock(dp, XFS_ILOCK_EXCL);
  	return error;
  }
  
  /*
   * Generic handler routine to remove a name from an attribute list.
   * Transitions attribute list from Btree to shortform as necessary.
   */
  int
  xfs_attr_remove(
  	struct xfs_inode	*dp,
  	const unsigned char	*name,
  	int			flags)
  {
  	struct xfs_mount	*mp = dp->i_mount;
  	struct xfs_da_args	args;
  	struct xfs_bmap_free	flist;
  	xfs_fsblock_t		firstblock;
  	int			error;
  
  	XFS_STATS_INC(xs_attr_remove);
  
  	if (XFS_FORCED_SHUTDOWN(dp->i_mount))
  		return -EIO;
  
  	if (!xfs_inode_hasattr(dp))
  		return -ENOATTR;
  
  	error = xfs_attr_args_init(&args, dp, name, flags);
  	if (error)
  		return error;
  
  	args.firstblock = &firstblock;
  	args.flist = &flist;
  
  	/*
  	 * we have no control over the attribute names that userspace passes us
  	 * to remove, so we have to allow the name lookup prior to attribute
  	 * removal to fail.
  	 */
  	args.op_flags = XFS_DA_OP_OKNOENT;
  
  	error = xfs_qm_dqattach(dp, 0);
  	if (error)
  		return error;
  
  	/*
  	 * Start our first transaction of the day.
  	 *
  	 * All future transactions during this code must be "chained" off
  	 * this one via the trans_dup() call.  All transactions will contain
  	 * the inode, and the inode will always be marked with trans_ihold().
  	 * Since the inode will be locked in all transactions, we must log
  	 * the inode in every transaction to let it float upward through
  	 * the log.
  	 */
  	args.trans = xfs_trans_alloc(mp, XFS_TRANS_ATTR_RM);
  
  	/*
  	 * Root fork attributes can use reserved data blocks for this
  	 * operation if necessary
  	 */
  
  	if (flags & ATTR_ROOT)
  		args.trans->t_flags |= XFS_TRANS_RESERVE;
  
  	error = xfs_trans_reserve(args.trans, &M_RES(mp)->tr_attrrm,
  				  XFS_ATTRRM_SPACE_RES(mp), 0);
  	if (error) {
  		xfs_trans_cancel(args.trans, 0);
  		return error;
  	}
  
  	xfs_ilock(dp, XFS_ILOCK_EXCL);
  	/*
  	 * No need to make quota reservations here. We expect to release some
  	 * blocks not allocate in the common case.
  	 */
  	xfs_trans_ijoin(args.trans, dp, 0);
  
  	if (!xfs_inode_hasattr(dp)) {
  		error = -ENOATTR;
  	} else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
  		ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
  		error = xfs_attr_shortform_remove(&args);
  	} else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
  		error = xfs_attr_leaf_removename(&args);
  	} else {
  		error = xfs_attr_node_removename(&args);
  	}
  
  	if (error)
  		goto out;
  
  	/*
  	 * If this is a synchronous mount, make sure that the
  	 * transaction goes to disk before returning to the user.
  	 */
  	if (mp->m_flags & XFS_MOUNT_WSYNC)
  		xfs_trans_set_sync(args.trans);
  
  	if ((flags & ATTR_KERNOTIME) == 0)
  		xfs_trans_ichgtime(args.trans, dp, XFS_ICHGTIME_CHG);
  
  	/*
  	 * Commit the last in the sequence of transactions.
  	 */
  	xfs_trans_log_inode(args.trans, dp, XFS_ILOG_CORE);
  	error = xfs_trans_commit(args.trans, XFS_TRANS_RELEASE_LOG_RES);
  	xfs_iunlock(dp, XFS_ILOCK_EXCL);
  
  	return error;
  
  out:
  	if (args.trans) {
  		xfs_trans_cancel(args.trans,
  			XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
  	}
  	xfs_iunlock(dp, XFS_ILOCK_EXCL);
  	return error;
  }
  
  /*========================================================================
   * External routines when attribute list is inside the inode
   *========================================================================*/
  
  /*
   * Add a name to the shortform attribute list structure
   * This is the external routine.
   */
  STATIC int
  xfs_attr_shortform_addname(xfs_da_args_t *args)
  {
  	int newsize, forkoff, retval;
  
  	trace_xfs_attr_sf_addname(args);
  
  	retval = xfs_attr_shortform_lookup(args);
  	if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
  		return retval;
  	} else if (retval == -EEXIST) {
  		if (args->flags & ATTR_CREATE)
  			return retval;
  		retval = xfs_attr_shortform_remove(args);
  		ASSERT(retval == 0);
  	}
  
  	if (args->namelen >= XFS_ATTR_SF_ENTSIZE_MAX ||
  	    args->valuelen >= XFS_ATTR_SF_ENTSIZE_MAX)
  		return -ENOSPC;
  
  	newsize = XFS_ATTR_SF_TOTSIZE(args->dp);
  	newsize += XFS_ATTR_SF_ENTSIZE_BYNAME(args->namelen, args->valuelen);
  
  	forkoff = xfs_attr_shortform_bytesfit(args->dp, newsize);
  	if (!forkoff)
  		return -ENOSPC;
  
  	xfs_attr_shortform_add(args, forkoff);
  	return 0;
  }
  
  
  /*========================================================================
   * External routines when attribute list is one block
   *========================================================================*/
  
  /*
   * Add a name to the leaf attribute list structure
   *
   * This leaf block cannot have a "remote" value, we only call this routine
   * if bmap_one_block() says there is only one block (ie: no remote blks).
   */
  STATIC int
  xfs_attr_leaf_addname(xfs_da_args_t *args)
  {
  	xfs_inode_t *dp;
  	struct xfs_buf *bp;
  	int retval, error, committed, forkoff;
  
  	trace_xfs_attr_leaf_addname(args);
  
  	/*
  	 * Read the (only) block in the attribute list in.
  	 */
  	dp = args->dp;
  	args->blkno = 0;
  	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
  	if (error)
  		return error;
  
  	/*
  	 * Look up the given attribute in the leaf block.  Figure out if
  	 * the given flags produce an error or call for an atomic rename.
  	 */
  	retval = xfs_attr3_leaf_lookup_int(bp, args);
  	if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
  		xfs_trans_brelse(args->trans, bp);
  		return retval;
  	} else if (retval == -EEXIST) {
  		if (args->flags & ATTR_CREATE) {	/* pure create op */
  			xfs_trans_brelse(args->trans, bp);
  			return retval;
  		}
  
  		trace_xfs_attr_leaf_replace(args);
  
  		/* save the attribute state for later removal*/
  		args->op_flags |= XFS_DA_OP_RENAME;	/* an atomic rename */
  		args->blkno2 = args->blkno;		/* set 2nd entry info*/
  		args->index2 = args->index;
  		args->rmtblkno2 = args->rmtblkno;
  		args->rmtblkcnt2 = args->rmtblkcnt;
  		args->rmtvaluelen2 = args->rmtvaluelen;
  
  		/*
  		 * clear the remote attr state now that it is saved so that the
  		 * values reflect the state of the attribute we are about to
  		 * add, not the attribute we just found and will remove later.
  		 */
  		args->rmtblkno = 0;
  		args->rmtblkcnt = 0;
  		args->rmtvaluelen = 0;
  	}
  
  	/*
  	 * Add the attribute to the leaf block, transitioning to a Btree
  	 * if required.
  	 */
  	retval = xfs_attr3_leaf_add(bp, args);
  	if (retval == -ENOSPC) {
  		/*
  		 * Promote the attribute list to the Btree format, then
  		 * Commit that transaction so that the node_addname() call
  		 * can manage its own transactions.
  		 */
  		xfs_bmap_init(args->flist, args->firstblock);
  		error = xfs_attr3_leaf_to_node(args);
  		if (!error) {
  			error = xfs_bmap_finish(&args->trans, args->flist,
  						&committed);
  		}
  		if (error) {
  			ASSERT(committed);
  			args->trans = NULL;
  			xfs_bmap_cancel(args->flist);
  			return error;
  		}
  
  		/*
  		 * bmap_finish() may have committed the last trans and started
  		 * a new one.  We need the inode to be in all transactions.
  		 */
  		if (committed)
  			xfs_trans_ijoin(args->trans, dp, 0);
  
  		/*
  		 * Commit the current trans (including the inode) and start
  		 * a new one.
  		 */
  		error = xfs_trans_roll(&args->trans, dp);
  		if (error)
  			return error;
  
  		/*
  		 * Fob the whole rest of the problem off on the Btree code.
  		 */
  		error = xfs_attr_node_addname(args);
  		return error;
  	}
  
  	/*
  	 * Commit the transaction that added the attr name so that
  	 * later routines can manage their own transactions.
  	 */
  	error = xfs_trans_roll(&args->trans, dp);
  	if (error)
  		return error;
  
  	/*
  	 * If there was an out-of-line value, allocate the blocks we
  	 * identified for its storage and copy the value.  This is done
  	 * after we create the attribute so that we don't overflow the
  	 * maximum size of a transaction and/or hit a deadlock.
  	 */
  	if (args->rmtblkno > 0) {
  		error = xfs_attr_rmtval_set(args);
  		if (error)
  			return error;
  	}
  
  	/*
  	 * If this is an atomic rename operation, we must "flip" the
  	 * incomplete flags on the "new" and "old" attribute/value pairs
  	 * so that one disappears and one appears atomically.  Then we
  	 * must remove the "old" attribute/value pair.
  	 */
  	if (args->op_flags & XFS_DA_OP_RENAME) {
  		/*
  		 * In a separate transaction, set the incomplete flag on the
  		 * "old" attr and clear the incomplete flag on the "new" attr.
  		 */
  		error = xfs_attr3_leaf_flipflags(args);
  		if (error)
  			return error;
  
  		/*
  		 * Dismantle the "old" attribute/value pair by removing
  		 * a "remote" value (if it exists).
  		 */
  		args->index = args->index2;
  		args->blkno = args->blkno2;
  		args->rmtblkno = args->rmtblkno2;
  		args->rmtblkcnt = args->rmtblkcnt2;
  		args->rmtvaluelen = args->rmtvaluelen2;
  		if (args->rmtblkno) {
  			error = xfs_attr_rmtval_remove(args);
  			if (error)
  				return error;
  		}
  
  		/*
  		 * Read in the block containing the "old" attr, then
  		 * remove the "old" attr from that block (neat, huh!)
  		 */
  		error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
  					   -1, &bp);
  		if (error)
  			return error;
  
  		xfs_attr3_leaf_remove(bp, args);
  
  		/*
  		 * If the result is small enough, shrink it all into the inode.
  		 */
  		if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
  			xfs_bmap_init(args->flist, args->firstblock);
  			error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
  			/* bp is gone due to xfs_da_shrink_inode */
  			if (!error) {
  				error = xfs_bmap_finish(&args->trans,
  							args->flist,
  							&committed);
  			}
  			if (error) {
  				ASSERT(committed);
  				args->trans = NULL;
  				xfs_bmap_cancel(args->flist);
  				return error;
  			}
  
  			/*
  			 * bmap_finish() may have committed the last trans
  			 * and started a new one.  We need the inode to be
  			 * in all transactions.
  			 */
  			if (committed)
  				xfs_trans_ijoin(args->trans, dp, 0);
  		}
  
  		/*
  		 * Commit the remove and start the next trans in series.
  		 */
  		error = xfs_trans_roll(&args->trans, dp);
  
  	} else if (args->rmtblkno > 0) {
  		/*
  		 * Added a "remote" value, just clear the incomplete flag.
  		 */
  		error = xfs_attr3_leaf_clearflag(args);
  	}
  	return error;
  }
  
  /*
   * Remove a name from the leaf attribute list structure
   *
   * This leaf block cannot have a "remote" value, we only call this routine
   * if bmap_one_block() says there is only one block (ie: no remote blks).
   */
  STATIC int
  xfs_attr_leaf_removename(xfs_da_args_t *args)
  {
  	xfs_inode_t *dp;
  	struct xfs_buf *bp;
  	int error, committed, forkoff;
  
  	trace_xfs_attr_leaf_removename(args);
  
  	/*
  	 * Remove the attribute.
  	 */
  	dp = args->dp;
  	args->blkno = 0;
  	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
  	if (error)
  		return error;
  
  	error = xfs_attr3_leaf_lookup_int(bp, args);
  	if (error == -ENOATTR) {
  		xfs_trans_brelse(args->trans, bp);
  		return error;
  	}
  
  	xfs_attr3_leaf_remove(bp, args);
  
  	/*
  	 * If the result is small enough, shrink it all into the inode.
  	 */
  	if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
  		xfs_bmap_init(args->flist, args->firstblock);
  		error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
  		/* bp is gone due to xfs_da_shrink_inode */
  		if (!error) {
  			error = xfs_bmap_finish(&args->trans, args->flist,
  						&committed);
  		}
  		if (error) {
  			ASSERT(committed);
  			args->trans = NULL;
  			xfs_bmap_cancel(args->flist);
  			return error;
  		}
  
  		/*
  		 * bmap_finish() may have committed the last trans and started
  		 * a new one.  We need the inode to be in all transactions.
  		 */
  		if (committed)
  			xfs_trans_ijoin(args->trans, dp, 0);
  	}
  	return 0;
  }
  
  /*
   * Look up a name in a leaf attribute list structure.
   *
   * This leaf block cannot have a "remote" value, we only call this routine
   * if bmap_one_block() says there is only one block (ie: no remote blks).
   */
  STATIC int
  xfs_attr_leaf_get(xfs_da_args_t *args)
  {
  	struct xfs_buf *bp;
  	int error;
  
  	trace_xfs_attr_leaf_get(args);
  
  	args->blkno = 0;
  	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
  	if (error)
  		return error;
  
  	error = xfs_attr3_leaf_lookup_int(bp, args);
  	if (error != -EEXIST)  {
  		xfs_trans_brelse(args->trans, bp);
  		return error;
  	}
  	error = xfs_attr3_leaf_getvalue(bp, args);
  	xfs_trans_brelse(args->trans, bp);
  	if (!error && (args->rmtblkno > 0) && !(args->flags & ATTR_KERNOVAL)) {
  		error = xfs_attr_rmtval_get(args);
  	}
  	return error;
  }
  
  /*========================================================================
   * External routines when attribute list size > geo->blksize
   *========================================================================*/
  
  /*
   * Add a name to a Btree-format attribute list.
   *
   * This will involve walking down the Btree, and may involve splitting
   * leaf nodes and even splitting intermediate nodes up to and including
   * the root node (a special case of an intermediate node).
   *
   * "Remote" attribute values confuse the issue and atomic rename operations
   * add a whole extra layer of confusion on top of that.
   */
  STATIC int
  xfs_attr_node_addname(xfs_da_args_t *args)
  {
  	xfs_da_state_t *state;
  	xfs_da_state_blk_t *blk;
  	xfs_inode_t *dp;
  	xfs_mount_t *mp;
  	int committed, retval, error;
  
  	trace_xfs_attr_node_addname(args);
  
  	/*
  	 * Fill in bucket of arguments/results/context to carry around.
  	 */
  	dp = args->dp;
  	mp = dp->i_mount;
  restart:
  	state = xfs_da_state_alloc();
  	state->args = args;
  	state->mp = mp;
  
  	/*
  	 * Search to see if name already exists, and get back a pointer
  	 * to where it should go.
  	 */
  	error = xfs_da3_node_lookup_int(state, &retval);
  	if (error)
  		goto out;
  	blk = &state->path.blk[ state->path.active-1 ];
  	ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
  	if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
  		goto out;
  	} else if (retval == -EEXIST) {
  		if (args->flags & ATTR_CREATE)
  			goto out;
  
  		trace_xfs_attr_node_replace(args);
  
  		/* save the attribute state for later removal*/
  		args->op_flags |= XFS_DA_OP_RENAME;	/* atomic rename op */
  		args->blkno2 = args->blkno;		/* set 2nd entry info*/
  		args->index2 = args->index;
  		args->rmtblkno2 = args->rmtblkno;
  		args->rmtblkcnt2 = args->rmtblkcnt;
  		args->rmtvaluelen2 = args->rmtvaluelen;
  
  		/*
  		 * clear the remote attr state now that it is saved so that the
  		 * values reflect the state of the attribute we are about to
  		 * add, not the attribute we just found and will remove later.
  		 */
  		args->rmtblkno = 0;
  		args->rmtblkcnt = 0;
  		args->rmtvaluelen = 0;
  	}
  
  	retval = xfs_attr3_leaf_add(blk->bp, state->args);
  	if (retval == -ENOSPC) {
  		if (state->path.active == 1) {
  			/*
  			 * Its really a single leaf node, but it had
  			 * out-of-line values so it looked like it *might*
  			 * have been a b-tree.
  			 */
  			xfs_da_state_free(state);
  			state = NULL;
  			xfs_bmap_init(args->flist, args->firstblock);
  			error = xfs_attr3_leaf_to_node(args);
  			if (!error) {
  				error = xfs_bmap_finish(&args->trans,
  							args->flist,
  							&committed);
  			}
  			if (error) {
  				ASSERT(committed);
  				args->trans = NULL;
  				xfs_bmap_cancel(args->flist);
  				goto out;
  			}
  
  			/*
  			 * bmap_finish() may have committed the last trans
  			 * and started a new one.  We need the inode to be
  			 * in all transactions.
  			 */
  			if (committed)
  				xfs_trans_ijoin(args->trans, dp, 0);
  
  			/*
  			 * Commit the node conversion and start the next
  			 * trans in the chain.
  			 */
  			error = xfs_trans_roll(&args->trans, dp);
  			if (error)
  				goto out;
  
  			goto restart;
  		}
  
  		/*
  		 * Split as many Btree elements as required.
  		 * This code tracks the new and old attr's location
  		 * in the index/blkno/rmtblkno/rmtblkcnt fields and
  		 * in the index2/blkno2/rmtblkno2/rmtblkcnt2 fields.
  		 */
  		xfs_bmap_init(args->flist, args->firstblock);
  		error = xfs_da3_split(state);
  		if (!error) {
  			error = xfs_bmap_finish(&args->trans, args->flist,
  						&committed);
  		}
  		if (error) {
  			ASSERT(committed);
  			args->trans = NULL;
  			xfs_bmap_cancel(args->flist);
  			goto out;
  		}
  
  		/*
  		 * bmap_finish() may have committed the last trans and started
  		 * a new one.  We need the inode to be in all transactions.
  		 */
  		if (committed)
  			xfs_trans_ijoin(args->trans, dp, 0);
  	} else {
  		/*
  		 * Addition succeeded, update Btree hashvals.
  		 */
  		xfs_da3_fixhashpath(state, &state->path);
  	}
  
  	/*
  	 * Kill the state structure, we're done with it and need to
  	 * allow the buffers to come back later.
  	 */
  	xfs_da_state_free(state);
  	state = NULL;
  
  	/*
  	 * Commit the leaf addition or btree split and start the next
  	 * trans in the chain.
  	 */
  	error = xfs_trans_roll(&args->trans, dp);
  	if (error)
  		goto out;
  
  	/*
  	 * If there was an out-of-line value, allocate the blocks we
  	 * identified for its storage and copy the value.  This is done
  	 * after we create the attribute so that we don't overflow the
  	 * maximum size of a transaction and/or hit a deadlock.
  	 */
  	if (args->rmtblkno > 0) {
  		error = xfs_attr_rmtval_set(args);
  		if (error)
  			return error;
  	}
  
  	/*
  	 * If this is an atomic rename operation, we must "flip" the
  	 * incomplete flags on the "new" and "old" attribute/value pairs
  	 * so that one disappears and one appears atomically.  Then we
  	 * must remove the "old" attribute/value pair.
  	 */
  	if (args->op_flags & XFS_DA_OP_RENAME) {
  		/*
  		 * In a separate transaction, set the incomplete flag on the
  		 * "old" attr and clear the incomplete flag on the "new" attr.
  		 */
  		error = xfs_attr3_leaf_flipflags(args);
  		if (error)
  			goto out;
  
  		/*
  		 * Dismantle the "old" attribute/value pair by removing
  		 * a "remote" value (if it exists).
  		 */
  		args->index = args->index2;
  		args->blkno = args->blkno2;
  		args->rmtblkno = args->rmtblkno2;
  		args->rmtblkcnt = args->rmtblkcnt2;
  		args->rmtvaluelen = args->rmtvaluelen2;
  		if (args->rmtblkno) {
  			error = xfs_attr_rmtval_remove(args);
  			if (error)
  				return error;
  		}
  
  		/*
  		 * Re-find the "old" attribute entry after any split ops.
  		 * The INCOMPLETE flag means that we will find the "old"
  		 * attr, not the "new" one.
  		 */
  		args->flags |= XFS_ATTR_INCOMPLETE;
  		state = xfs_da_state_alloc();
  		state->args = args;
  		state->mp = mp;
  		state->inleaf = 0;
  		error = xfs_da3_node_lookup_int(state, &retval);
  		if (error)
  			goto out;
  
  		/*
  		 * Remove the name and update the hashvals in the tree.
  		 */
  		blk = &state->path.blk[ state->path.active-1 ];
  		ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
  		error = xfs_attr3_leaf_remove(blk->bp, args);
  		xfs_da3_fixhashpath(state, &state->path);
  
  		/*
  		 * Check to see if the tree needs to be collapsed.
  		 */
  		if (retval && (state->path.active > 1)) {
  			xfs_bmap_init(args->flist, args->firstblock);
  			error = xfs_da3_join(state);
  			if (!error) {
  				error = xfs_bmap_finish(&args->trans,
  							args->flist,
  							&committed);
  			}
  			if (error) {
  				ASSERT(committed);
  				args->trans = NULL;
  				xfs_bmap_cancel(args->flist);
  				goto out;
  			}
  
  			/*
  			 * bmap_finish() may have committed the last trans
  			 * and started a new one.  We need the inode to be
  			 * in all transactions.
  			 */
  			if (committed)
  				xfs_trans_ijoin(args->trans, dp, 0);
  		}
  
  		/*
  		 * Commit and start the next trans in the chain.
  		 */
  		error = xfs_trans_roll(&args->trans, dp);
  		if (error)
  			goto out;
  
  	} else if (args->rmtblkno > 0) {
  		/*
  		 * Added a "remote" value, just clear the incomplete flag.
  		 */
  		error = xfs_attr3_leaf_clearflag(args);
  		if (error)
  			goto out;
  	}
  	retval = error = 0;
  
  out:
  	if (state)
  		xfs_da_state_free(state);
  	if (error)
  		return error;
  	return retval;
  }
  
  /*
   * Remove a name from a B-tree attribute list.
   *
   * This will involve walking down the Btree, and may involve joining
   * leaf nodes and even joining intermediate nodes up to and including
   * the root node (a special case of an intermediate node).
   */
  STATIC int
  xfs_attr_node_removename(xfs_da_args_t *args)
  {
  	xfs_da_state_t *state;
  	xfs_da_state_blk_t *blk;
  	xfs_inode_t *dp;
  	struct xfs_buf *bp;
  	int retval, error, committed, forkoff;
  
  	trace_xfs_attr_node_removename(args);
  
  	/*
  	 * Tie a string around our finger to remind us where we are.
  	 */
  	dp = args->dp;
  	state = xfs_da_state_alloc();
  	state->args = args;
  	state->mp = dp->i_mount;
  
  	/*
  	 * Search to see if name exists, and get back a pointer to it.
  	 */
  	error = xfs_da3_node_lookup_int(state, &retval);
  	if (error || (retval != -EEXIST)) {
  		if (error == 0)
  			error = retval;
  		goto out;
  	}
  
  	/*
  	 * If there is an out-of-line value, de-allocate the blocks.
  	 * This is done before we remove the attribute so that we don't
  	 * overflow the maximum size of a transaction and/or hit a deadlock.
  	 */
  	blk = &state->path.blk[ state->path.active-1 ];
  	ASSERT(blk->bp != NULL);
  	ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
  	if (args->rmtblkno > 0) {
  		/*
  		 * Fill in disk block numbers in the state structure
  		 * so that we can get the buffers back after we commit
  		 * several transactions in the following calls.
  		 */
  		error = xfs_attr_fillstate(state);
  		if (error)
  			goto out;
  
  		/*
  		 * Mark the attribute as INCOMPLETE, then bunmapi() the
  		 * remote value.
  		 */
  		error = xfs_attr3_leaf_setflag(args);
  		if (error)
  			goto out;
  		error = xfs_attr_rmtval_remove(args);
  		if (error)
  			goto out;
  
  		/*
  		 * Refill the state structure with buffers, the prior calls
  		 * released our buffers.
  		 */
  		error = xfs_attr_refillstate(state);
  		if (error)
  			goto out;
  	}
  
  	/*
  	 * Remove the name and update the hashvals in the tree.
  	 */
  	blk = &state->path.blk[ state->path.active-1 ];
  	ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
  	retval = xfs_attr3_leaf_remove(blk->bp, args);
  	xfs_da3_fixhashpath(state, &state->path);
  
  	/*
  	 * Check to see if the tree needs to be collapsed.
  	 */
  	if (retval && (state->path.active > 1)) {
  		xfs_bmap_init(args->flist, args->firstblock);
  		error = xfs_da3_join(state);
  		if (!error) {
  			error = xfs_bmap_finish(&args->trans, args->flist,
  						&committed);
  		}
  		if (error) {
  			ASSERT(committed);
  			args->trans = NULL;
  			xfs_bmap_cancel(args->flist);
  			goto out;
  		}
  
  		/*
  		 * bmap_finish() may have committed the last trans and started
  		 * a new one.  We need the inode to be in all transactions.
  		 */
  		if (committed)
  			xfs_trans_ijoin(args->trans, dp, 0);
  
  		/*
  		 * Commit the Btree join operation and start a new trans.
  		 */
  		error = xfs_trans_roll(&args->trans, dp);
  		if (error)
  			goto out;
  	}
  
  	/*
  	 * If the result is small enough, push it all into the inode.
  	 */
  	if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
  		/*
  		 * Have to get rid of the copy of this dabuf in the state.
  		 */
  		ASSERT(state->path.active == 1);
  		ASSERT(state->path.blk[0].bp);
  		state->path.blk[0].bp = NULL;
  
  		error = xfs_attr3_leaf_read(args->trans, args->dp, 0, -1, &bp);
  		if (error)
  			goto out;
  
  		if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
  			xfs_bmap_init(args->flist, args->firstblock);
  			error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
  			/* bp is gone due to xfs_da_shrink_inode */
  			if (!error) {
  				error = xfs_bmap_finish(&args->trans,
  							args->flist,
  							&committed);
  			}
  			if (error) {
  				ASSERT(committed);
  				args->trans = NULL;
  				xfs_bmap_cancel(args->flist);
  				goto out;
  			}
  
  			/*
  			 * bmap_finish() may have committed the last trans
  			 * and started a new one.  We need the inode to be
  			 * in all transactions.
  			 */
  			if (committed)
  				xfs_trans_ijoin(args->trans, dp, 0);
  		} else
  			xfs_trans_brelse(args->trans, bp);
  	}
  	error = 0;
  
  out:
  	xfs_da_state_free(state);
  	return error;
  }
  
  /*
   * Fill in the disk block numbers in the state structure for the buffers
   * that are attached to the state structure.
   * This is done so that we can quickly reattach ourselves to those buffers
   * after some set of transaction commits have released these buffers.
   */
  STATIC int
  xfs_attr_fillstate(xfs_da_state_t *state)
  {
  	xfs_da_state_path_t *path;
  	xfs_da_state_blk_t *blk;
  	int level;
  
  	trace_xfs_attr_fillstate(state->args);
  
  	/*
  	 * Roll down the "path" in the state structure, storing the on-disk
  	 * block number for those buffers in the "path".
  	 */
  	path = &state->path;
  	ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
  	for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
  		if (blk->bp) {
  			blk->disk_blkno = XFS_BUF_ADDR(blk->bp);
  			blk->bp = NULL;
  		} else {
  			blk->disk_blkno = 0;
  		}
  	}
  
  	/*
  	 * Roll down the "altpath" in the state structure, storing the on-disk
  	 * block number for those buffers in the "altpath".
  	 */
  	path = &state->altpath;
  	ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
  	for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
  		if (blk->bp) {
  			blk->disk_blkno = XFS_BUF_ADDR(blk->bp);
  			blk->bp = NULL;
  		} else {
  			blk->disk_blkno = 0;
  		}
  	}
  
  	return 0;
  }
  
  /*
   * Reattach the buffers to the state structure based on the disk block
   * numbers stored in the state structure.
   * This is done after some set of transaction commits have released those
   * buffers from our grip.
   */
  STATIC int
  xfs_attr_refillstate(xfs_da_state_t *state)
  {
  	xfs_da_state_path_t *path;
  	xfs_da_state_blk_t *blk;
  	int level, error;
  
  	trace_xfs_attr_refillstate(state->args);
  
  	/*
  	 * Roll down the "path" in the state structure, storing the on-disk
  	 * block number for those buffers in the "path".
  	 */
  	path = &state->path;
  	ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
  	for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
  		if (blk->disk_blkno) {
  			error = xfs_da3_node_read(state->args->trans,
  						state->args->dp,
  						blk->blkno, blk->disk_blkno,
  						&blk->bp, XFS_ATTR_FORK);
  			if (error)
  				return error;
  		} else {
  			blk->bp = NULL;
  		}
  	}
  
  	/*
  	 * Roll down the "altpath" in the state structure, storing the on-disk
  	 * block number for those buffers in the "altpath".
  	 */
  	path = &state->altpath;
  	ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
  	for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
  		if (blk->disk_blkno) {
  			error = xfs_da3_node_read(state->args->trans,
  						state->args->dp,
  						blk->blkno, blk->disk_blkno,
  						&blk->bp, XFS_ATTR_FORK);
  			if (error)
  				return error;
  		} else {
  			blk->bp = NULL;
  		}
  	}
  
  	return 0;
  }
  
  /*
   * Look up a filename in a node attribute list.
   *
   * This routine gets called for any attribute fork that has more than one
   * block, ie: both true Btree attr lists and for single-leaf-blocks with
   * "remote" values taking up more blocks.
   */
  STATIC int
  xfs_attr_node_get(xfs_da_args_t *args)
  {
  	xfs_da_state_t *state;
  	xfs_da_state_blk_t *blk;
  	int error, retval;
  	int i;
  
  	trace_xfs_attr_node_get(args);
  
  	state = xfs_da_state_alloc();
  	state->args = args;
  	state->mp = args->dp->i_mount;
  
  	/*
  	 * Search to see if name exists, and get back a pointer to it.
  	 */
  	error = xfs_da3_node_lookup_int(state, &retval);
  	if (error) {
  		retval = error;
  	} else if (retval == -EEXIST) {
  		blk = &state->path.blk[ state->path.active-1 ];
  		ASSERT(blk->bp != NULL);
  		ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
  
  		/*
  		 * Get the value, local or "remote"
  		 */
  		retval = xfs_attr3_leaf_getvalue(blk->bp, args);
  		if (!retval && (args->rmtblkno > 0)
  		    && !(args->flags & ATTR_KERNOVAL)) {
  			retval = xfs_attr_rmtval_get(args);
  		}
  	}
  
  	/*
  	 * If not in a transaction, we have to release all the buffers.
  	 */
  	for (i = 0; i < state->path.active; i++) {
  		xfs_trans_brelse(args->trans, state->path.blk[i].bp);
  		state->path.blk[i].bp = NULL;
  	}
  
  	xfs_da_state_free(state);
  	return retval;
  }
  