/* -*- mode: c; c-basic-offset: 8; -*-
   * vim: noexpandtab sw=8 ts=8 sts=0:
   *
   * xattr.c
   *

   * Copyright (C) 2004, 2008 Oracle.  All rights reserved.

   *

   * CREDITS:

   * Lots of code in this file is copy from linux/fs/ext3/xattr.c.
   * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de>

   *

   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public

   * License version 2 as published by the Free Software Foundation.

   *
   * This program 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.

   */

  #include <linux/capability.h>
  #include <linux/fs.h>
  #include <linux/types.h>
  #include <linux/slab.h>
  #include <linux/highmem.h>
  #include <linux/pagemap.h>
  #include <linux/uio.h>
  #include <linux/sched.h>
  #include <linux/splice.h>
  #include <linux/mount.h>
  #include <linux/writeback.h>
  #include <linux/falloc.h>

  #include <linux/sort.h>

  #include <linux/init.h>
  #include <linux/module.h>
  #include <linux/string.h>

  #include <linux/security.h>

  #include <cluster/masklog.h>
  
  #include "ocfs2.h"
  #include "alloc.h"

  #include "blockcheck.h"

  #include "dlmglue.h"
  #include "file.h"

  #include "symlink.h"
  #include "sysfile.h"

  #include "inode.h"
  #include "journal.h"
  #include "ocfs2_fs.h"
  #include "suballoc.h"
  #include "uptodate.h"
  #include "buffer_head_io.h"

  #include "super.h"

  #include "xattr.h"

  #include "refcounttree.h"

  #include "acl.h"

  #include "ocfs2_trace.h"

  
  struct ocfs2_xattr_def_value_root {
  	struct ocfs2_xattr_value_root	xv;
  	struct ocfs2_extent_rec		er;
  };

  struct ocfs2_xattr_bucket {

  	/* The inode these xattrs are associated with */
  	struct inode *bu_inode;
  
  	/* The actual buffers that make up the bucket */

  	struct buffer_head *bu_bhs[OCFS2_XATTR_MAX_BLOCKS_PER_BUCKET];

  
  	/* How many blocks make up one bucket for this filesystem */
  	int bu_blocks;

  };

  struct ocfs2_xattr_set_ctxt {

  	handle_t *handle;

  	struct ocfs2_alloc_context *meta_ac;
  	struct ocfs2_alloc_context *data_ac;
  	struct ocfs2_cached_dealloc_ctxt dealloc;

  	int set_abort;

  };

  #define OCFS2_XATTR_ROOT_SIZE	(sizeof(struct ocfs2_xattr_def_value_root))
  #define OCFS2_XATTR_INLINE_SIZE	80

  #define OCFS2_XATTR_HEADER_GAP	4

  #define OCFS2_XATTR_FREE_IN_IBODY	(OCFS2_MIN_XATTR_INLINE_SIZE \
  					 - sizeof(struct ocfs2_xattr_header) \

  					 - OCFS2_XATTR_HEADER_GAP)

  #define OCFS2_XATTR_FREE_IN_BLOCK(ptr)	((ptr)->i_sb->s_blocksize \
  					 - sizeof(struct ocfs2_xattr_block) \
  					 - sizeof(struct ocfs2_xattr_header) \

  					 - OCFS2_XATTR_HEADER_GAP)

  
  static struct ocfs2_xattr_def_value_root def_xv = {
  	.xv.xr_list.l_count = cpu_to_le16(1),
  };

  const struct xattr_handler *ocfs2_xattr_handlers[] = {

  	&ocfs2_xattr_user_handler,

  	&ocfs2_xattr_acl_access_handler,
  	&ocfs2_xattr_acl_default_handler,

  	&ocfs2_xattr_trusted_handler,

  	&ocfs2_xattr_security_handler,

  	NULL
  };

  static const struct xattr_handler *ocfs2_xattr_handler_map[OCFS2_XATTR_MAX] = {

  	[OCFS2_XATTR_INDEX_USER]	= &ocfs2_xattr_user_handler,

  	[OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS]
  					= &ocfs2_xattr_acl_access_handler,
  	[OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT]
  					= &ocfs2_xattr_acl_default_handler,

  	[OCFS2_XATTR_INDEX_TRUSTED]	= &ocfs2_xattr_trusted_handler,

  	[OCFS2_XATTR_INDEX_SECURITY]	= &ocfs2_xattr_security_handler,

  };
  
  struct ocfs2_xattr_info {

  	int		xi_name_index;
  	const char	*xi_name;

  	int		xi_name_len;

  	const void	*xi_value;
  	size_t		xi_value_len;

  };
  
  struct ocfs2_xattr_search {
  	struct buffer_head *inode_bh;
  	/*
  	 * xattr_bh point to the block buffer head which has extended attribute
  	 * when extended attribute in inode, xattr_bh is equal to inode_bh.
  	 */
  	struct buffer_head *xattr_bh;
  	struct ocfs2_xattr_header *header;

  	struct ocfs2_xattr_bucket *bucket;

  	void *base;
  	void *end;
  	struct ocfs2_xattr_entry *here;
  	int not_found;
  };

  /* Operations on struct ocfs2_xa_entry */
  struct ocfs2_xa_loc;
  struct ocfs2_xa_loc_operations {
  	/*

  	 * Journal functions
  	 */
  	int (*xlo_journal_access)(handle_t *handle, struct ocfs2_xa_loc *loc,
  				  int type);
  	void (*xlo_journal_dirty)(handle_t *handle, struct ocfs2_xa_loc *loc);
  
  	/*

  	 * Return a pointer to the appropriate buffer in loc->xl_storage
  	 * at the given offset from loc->xl_header.
  	 */
  	void *(*xlo_offset_pointer)(struct ocfs2_xa_loc *loc, int offset);

  	/* Can we reuse the existing entry for the new value? */
  	int (*xlo_can_reuse)(struct ocfs2_xa_loc *loc,
  			     struct ocfs2_xattr_info *xi);
  
  	/* How much space is needed for the new value? */
  	int (*xlo_check_space)(struct ocfs2_xa_loc *loc,
  			       struct ocfs2_xattr_info *xi);
  
  	/*
  	 * Return the offset of the first name+value pair.  This is
  	 * the start of our downward-filling free space.
  	 */
  	int (*xlo_get_free_start)(struct ocfs2_xa_loc *loc);

  	/*
  	 * Remove the name+value at this location.  Do whatever is
  	 * appropriate with the remaining name+value pairs.
  	 */
  	void (*xlo_wipe_namevalue)(struct ocfs2_xa_loc *loc);

  
  	/* Fill xl_entry with a new entry */
  	void (*xlo_add_entry)(struct ocfs2_xa_loc *loc, u32 name_hash);
  
  	/* Add name+value storage to an entry */
  	void (*xlo_add_namevalue)(struct ocfs2_xa_loc *loc, int size);

  
  	/*
  	 * Initialize the value buf's access and bh fields for this entry.
  	 * ocfs2_xa_fill_value_buf() will handle the xv pointer.
  	 */
  	void (*xlo_fill_value_buf)(struct ocfs2_xa_loc *loc,
  				   struct ocfs2_xattr_value_buf *vb);

  };
  
  /*
   * Describes an xattr entry location.  This is a memory structure
   * tracking the on-disk structure.
   */
  struct ocfs2_xa_loc {

  	/* This xattr belongs to this inode */
  	struct inode *xl_inode;

  	/* The ocfs2_xattr_header inside the on-disk storage. Not NULL. */
  	struct ocfs2_xattr_header *xl_header;
  
  	/* Bytes from xl_header to the end of the storage */
  	int xl_size;
  
  	/*
  	 * The ocfs2_xattr_entry this location describes.  If this is
  	 * NULL, this location describes the on-disk structure where it
  	 * would have been.
  	 */
  	struct ocfs2_xattr_entry *xl_entry;
  
  	/*
  	 * Internal housekeeping
  	 */
  
  	/* Buffer(s) containing this entry */
  	void *xl_storage;
  
  	/* Operations on the storage backing this location */
  	const struct ocfs2_xa_loc_operations *xl_ops;
  };

  /*
   * Convenience functions to calculate how much space is needed for a
   * given name+value pair
   */
  static int namevalue_size(int name_len, uint64_t value_len)
  {
  	if (value_len > OCFS2_XATTR_INLINE_SIZE)
  		return OCFS2_XATTR_SIZE(name_len) + OCFS2_XATTR_ROOT_SIZE;
  	else
  		return OCFS2_XATTR_SIZE(name_len) + OCFS2_XATTR_SIZE(value_len);
  }
  
  static int namevalue_size_xi(struct ocfs2_xattr_info *xi)
  {
  	return namevalue_size(xi->xi_name_len, xi->xi_value_len);
  }
  
  static int namevalue_size_xe(struct ocfs2_xattr_entry *xe)
  {
  	u64 value_len = le64_to_cpu(xe->xe_value_size);
  
  	BUG_ON((value_len > OCFS2_XATTR_INLINE_SIZE) &&
  	       ocfs2_xattr_is_local(xe));
  	return namevalue_size(xe->xe_name_len, value_len);
  }

  static int ocfs2_xattr_bucket_get_name_value(struct super_block *sb,

  					     struct ocfs2_xattr_header *xh,
  					     int index,
  					     int *block_off,
  					     int *new_offset);

  static int ocfs2_xattr_block_find(struct inode *inode,
  				  int name_index,
  				  const char *name,
  				  struct ocfs2_xattr_search *xs);

  static int ocfs2_xattr_index_block_find(struct inode *inode,
  					struct buffer_head *root_bh,
  					int name_index,
  					const char *name,
  					struct ocfs2_xattr_search *xs);

  static int ocfs2_xattr_tree_list_index_block(struct inode *inode,

  					struct buffer_head *blk_bh,

  					char *buffer,
  					size_t buffer_size);

  static int ocfs2_xattr_create_index_block(struct inode *inode,

  					  struct ocfs2_xattr_search *xs,
  					  struct ocfs2_xattr_set_ctxt *ctxt);

  
  static int ocfs2_xattr_set_entry_index_block(struct inode *inode,
  					     struct ocfs2_xattr_info *xi,

  					     struct ocfs2_xattr_search *xs,
  					     struct ocfs2_xattr_set_ctxt *ctxt);

  typedef int (xattr_tree_rec_func)(struct inode *inode,
  				  struct buffer_head *root_bh,
  				  u64 blkno, u32 cpos, u32 len, void *para);
  static int ocfs2_iterate_xattr_index_block(struct inode *inode,
  					   struct buffer_head *root_bh,
  					   xattr_tree_rec_func *rec_func,
  					   void *para);
  static int ocfs2_delete_xattr_in_bucket(struct inode *inode,
  					struct ocfs2_xattr_bucket *bucket,
  					void *para);
  static int ocfs2_rm_xattr_cluster(struct inode *inode,
  				  struct buffer_head *root_bh,
  				  u64 blkno,
  				  u32 cpos,
  				  u32 len,
  				  void *para);

  static int ocfs2_mv_xattr_buckets(struct inode *inode, handle_t *handle,
  				  u64 src_blk, u64 last_blk, u64 to_blk,
  				  unsigned int start_bucket,
  				  u32 *first_hash);

  static int ocfs2_prepare_refcount_xattr(struct inode *inode,
  					struct ocfs2_dinode *di,
  					struct ocfs2_xattr_info *xi,
  					struct ocfs2_xattr_search *xis,
  					struct ocfs2_xattr_search *xbs,
  					struct ocfs2_refcount_tree **ref_tree,
  					int *meta_need,
  					int *credits);

  static int ocfs2_get_xattr_tree_value_root(struct super_block *sb,
  					   struct ocfs2_xattr_bucket *bucket,
  					   int offset,
  					   struct ocfs2_xattr_value_root **xv,
  					   struct buffer_head **bh);

  static inline u16 ocfs2_xattr_buckets_per_cluster(struct ocfs2_super *osb)
  {
  	return (1 << osb->s_clustersize_bits) / OCFS2_XATTR_BUCKET_SIZE;
  }
  
  static inline u16 ocfs2_blocks_per_xattr_bucket(struct super_block *sb)
  {
  	return OCFS2_XATTR_BUCKET_SIZE / (1 << sb->s_blocksize_bits);
  }

  #define bucket_blkno(_b) ((_b)->bu_bhs[0]->b_blocknr)

  #define bucket_block(_b, _n) ((_b)->bu_bhs[(_n)]->b_data)

  #define bucket_xh(_b) ((struct ocfs2_xattr_header *)bucket_block((_b), 0))

  static struct ocfs2_xattr_bucket *ocfs2_xattr_bucket_new(struct inode *inode)

  {

  	struct ocfs2_xattr_bucket *bucket;
  	int blks = ocfs2_blocks_per_xattr_bucket(inode->i_sb);

  	BUG_ON(blks > OCFS2_XATTR_MAX_BLOCKS_PER_BUCKET);
  
  	bucket = kzalloc(sizeof(struct ocfs2_xattr_bucket), GFP_NOFS);
  	if (bucket) {
  		bucket->bu_inode = inode;
  		bucket->bu_blocks = blks;
  	}
  
  	return bucket;
  }
  
  static void ocfs2_xattr_bucket_relse(struct ocfs2_xattr_bucket *bucket)
  {
  	int i;
  
  	for (i = 0; i < bucket->bu_blocks; i++) {

  		brelse(bucket->bu_bhs[i]);
  		bucket->bu_bhs[i] = NULL;
  	}
  }

  static void ocfs2_xattr_bucket_free(struct ocfs2_xattr_bucket *bucket)
  {
  	if (bucket) {
  		ocfs2_xattr_bucket_relse(bucket);
  		bucket->bu_inode = NULL;
  		kfree(bucket);
  	}
  }

  /*
   * A bucket that has never been written to disk doesn't need to be
   * read.  We just need the buffer_heads.  Don't call this for
   * buckets that are already on disk.  ocfs2_read_xattr_bucket() initializes
   * them fully.
   */

  static int ocfs2_init_xattr_bucket(struct ocfs2_xattr_bucket *bucket,

  				   u64 xb_blkno)
  {
  	int i, rc = 0;

  	for (i = 0; i < bucket->bu_blocks; i++) {
  		bucket->bu_bhs[i] = sb_getblk(bucket->bu_inode->i_sb,
  					      xb_blkno + i);

  		if (!bucket->bu_bhs[i]) {
  			rc = -EIO;
  			mlog_errno(rc);
  			break;
  		}

  		if (!ocfs2_buffer_uptodate(INODE_CACHE(bucket->bu_inode),

  					   bucket->bu_bhs[i]))

  			ocfs2_set_new_buffer_uptodate(INODE_CACHE(bucket->bu_inode),

  						      bucket->bu_bhs[i]);

  	}
  
  	if (rc)

  		ocfs2_xattr_bucket_relse(bucket);

  	return rc;
  }
  
  /* Read the xattr bucket at xb_blkno */

  static int ocfs2_read_xattr_bucket(struct ocfs2_xattr_bucket *bucket,

  				   u64 xb_blkno)
  {

  	int rc;

  	rc = ocfs2_read_blocks(INODE_CACHE(bucket->bu_inode), xb_blkno,

  			       bucket->bu_blocks, bucket->bu_bhs, 0,
  			       NULL);

  	if (!rc) {

  		spin_lock(&OCFS2_SB(bucket->bu_inode->i_sb)->osb_xattr_lock);

  		rc = ocfs2_validate_meta_ecc_bhs(bucket->bu_inode->i_sb,
  						 bucket->bu_bhs,
  						 bucket->bu_blocks,
  						 &bucket_xh(bucket)->xh_check);

  		spin_unlock(&OCFS2_SB(bucket->bu_inode->i_sb)->osb_xattr_lock);

  		if (rc)
  			mlog_errno(rc);
  	}

  	if (rc)

  		ocfs2_xattr_bucket_relse(bucket);

  	return rc;
  }

  static int ocfs2_xattr_bucket_journal_access(handle_t *handle,

  					     struct ocfs2_xattr_bucket *bucket,
  					     int type)
  {
  	int i, rc = 0;

  	for (i = 0; i < bucket->bu_blocks; i++) {

  		rc = ocfs2_journal_access(handle,
  					  INODE_CACHE(bucket->bu_inode),

  					  bucket->bu_bhs[i], type);
  		if (rc) {
  			mlog_errno(rc);
  			break;
  		}
  	}
  
  	return rc;
  }
  
  static void ocfs2_xattr_bucket_journal_dirty(handle_t *handle,

  					     struct ocfs2_xattr_bucket *bucket)
  {

  	int i;

  	spin_lock(&OCFS2_SB(bucket->bu_inode->i_sb)->osb_xattr_lock);

  	ocfs2_compute_meta_ecc_bhs(bucket->bu_inode->i_sb,
  				   bucket->bu_bhs, bucket->bu_blocks,
  				   &bucket_xh(bucket)->xh_check);

  	spin_unlock(&OCFS2_SB(bucket->bu_inode->i_sb)->osb_xattr_lock);

  	for (i = 0; i < bucket->bu_blocks; i++)

  		ocfs2_journal_dirty(handle, bucket->bu_bhs[i]);
  }

  static void ocfs2_xattr_bucket_copy_data(struct ocfs2_xattr_bucket *dest,

  					 struct ocfs2_xattr_bucket *src)
  {
  	int i;

  	int blocksize = src->bu_inode->i_sb->s_blocksize;
  
  	BUG_ON(dest->bu_blocks != src->bu_blocks);
  	BUG_ON(dest->bu_inode != src->bu_inode);

  	for (i = 0; i < src->bu_blocks; i++) {

  		memcpy(bucket_block(dest, i), bucket_block(src, i),
  		       blocksize);
  	}
  }

  static int ocfs2_validate_xattr_block(struct super_block *sb,
  				      struct buffer_head *bh)
  {

  	int rc;

  	struct ocfs2_xattr_block *xb =
  		(struct ocfs2_xattr_block *)bh->b_data;

  	trace_ocfs2_validate_xattr_block((unsigned long long)bh->b_blocknr);

  	BUG_ON(!buffer_uptodate(bh));
  
  	/*
  	 * If the ecc fails, we return the error but otherwise
  	 * leave the filesystem running.  We know any error is
  	 * local to this block.
  	 */
  	rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &xb->xb_check);
  	if (rc)
  		return rc;
  
  	/*
  	 * Errors after here are fatal
  	 */

  	if (!OCFS2_IS_VALID_XATTR_BLOCK(xb)) {
  		ocfs2_error(sb,
  			    "Extended attribute block #%llu has bad "
  			    "signature %.*s",
  			    (unsigned long long)bh->b_blocknr, 7,
  			    xb->xb_signature);
  		return -EINVAL;
  	}
  
  	if (le64_to_cpu(xb->xb_blkno) != bh->b_blocknr) {
  		ocfs2_error(sb,
  			    "Extended attribute block #%llu has an "
  			    "invalid xb_blkno of %llu",
  			    (unsigned long long)bh->b_blocknr,
  			    (unsigned long long)le64_to_cpu(xb->xb_blkno));
  		return -EINVAL;
  	}
  
  	if (le32_to_cpu(xb->xb_fs_generation) != OCFS2_SB(sb)->fs_generation) {
  		ocfs2_error(sb,
  			    "Extended attribute block #%llu has an invalid "
  			    "xb_fs_generation of #%u",
  			    (unsigned long long)bh->b_blocknr,
  			    le32_to_cpu(xb->xb_fs_generation));
  		return -EINVAL;
  	}
  
  	return 0;
  }
  
  static int ocfs2_read_xattr_block(struct inode *inode, u64 xb_blkno,
  				  struct buffer_head **bh)
  {
  	int rc;
  	struct buffer_head *tmp = *bh;

  	rc = ocfs2_read_block(INODE_CACHE(inode), xb_blkno, &tmp,

  			      ocfs2_validate_xattr_block);

  
  	/* If ocfs2_read_block() got us a new bh, pass it up. */
  	if (!rc && !*bh)
  		*bh = tmp;
  
  	return rc;
  }

  static inline const char *ocfs2_xattr_prefix(int name_index)

  {

  	const struct xattr_handler *handler = NULL;

  
  	if (name_index > 0 && name_index < OCFS2_XATTR_MAX)
  		handler = ocfs2_xattr_handler_map[name_index];

  	return handler ? handler->prefix : NULL;

  }

  static u32 ocfs2_xattr_name_hash(struct inode *inode,

  				 const char *name,

  				 int name_len)

  {
  	/* Get hash value of uuid from super block */
  	u32 hash = OCFS2_SB(inode->i_sb)->uuid_hash;
  	int i;

  	/* hash extended attribute name */
  	for (i = 0; i < name_len; i++) {
  		hash = (hash << OCFS2_HASH_SHIFT) ^
  		       (hash >> (8*sizeof(hash) - OCFS2_HASH_SHIFT)) ^
  		       *name++;
  	}
  
  	return hash;
  }

  static int ocfs2_xattr_entry_real_size(int name_len, size_t value_len)
  {

  	return namevalue_size(name_len, value_len) +
  		sizeof(struct ocfs2_xattr_entry);
  }

  static int ocfs2_xi_entry_usage(struct ocfs2_xattr_info *xi)
  {
  	return namevalue_size_xi(xi) +
  		sizeof(struct ocfs2_xattr_entry);
  }

  static int ocfs2_xe_entry_usage(struct ocfs2_xattr_entry *xe)
  {
  	return namevalue_size_xe(xe) +
  		sizeof(struct ocfs2_xattr_entry);

  }
  
  int ocfs2_calc_security_init(struct inode *dir,
  			     struct ocfs2_security_xattr_info *si,
  			     int *want_clusters,
  			     int *xattr_credits,
  			     struct ocfs2_alloc_context **xattr_ac)
  {
  	int ret = 0;
  	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
  	int s_size = ocfs2_xattr_entry_real_size(strlen(si->name),
  						 si->value_len);
  
  	/*
  	 * The max space of security xattr taken inline is
  	 * 256(name) + 80(value) + 16(entry) = 352 bytes,
  	 * So reserve one metadata block for it is ok.
  	 */
  	if (dir->i_sb->s_blocksize == OCFS2_MIN_BLOCKSIZE ||
  	    s_size > OCFS2_XATTR_FREE_IN_IBODY) {
  		ret = ocfs2_reserve_new_metadata_blocks(osb, 1, xattr_ac);
  		if (ret) {
  			mlog_errno(ret);
  			return ret;
  		}
  		*xattr_credits += OCFS2_XATTR_BLOCK_CREATE_CREDITS;
  	}
  
  	/* reserve clusters for xattr value which will be set in B tree*/

  	if (si->value_len > OCFS2_XATTR_INLINE_SIZE) {
  		int new_clusters = ocfs2_clusters_for_bytes(dir->i_sb,
  							    si->value_len);
  
  		*xattr_credits += ocfs2_clusters_to_blocks(dir->i_sb,
  							   new_clusters);
  		*want_clusters += new_clusters;
  	}

  	return ret;
  }

  int ocfs2_calc_xattr_init(struct inode *dir,
  			  struct buffer_head *dir_bh,

  			  umode_t mode,

  			  struct ocfs2_security_xattr_info *si,
  			  int *want_clusters,
  			  int *xattr_credits,

  			  int *want_meta)

  {
  	int ret = 0;
  	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);

  	int s_size = 0, a_size = 0, acl_len = 0, new_clusters;

  
  	if (si->enable)
  		s_size = ocfs2_xattr_entry_real_size(strlen(si->name),
  						     si->value_len);
  
  	if (osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL) {
  		acl_len = ocfs2_xattr_get_nolock(dir, dir_bh,
  					OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT,
  					"", NULL, 0);
  		if (acl_len > 0) {
  			a_size = ocfs2_xattr_entry_real_size(0, acl_len);
  			if (S_ISDIR(mode))
  				a_size <<= 1;
  		} else if (acl_len != 0 && acl_len != -ENODATA) {
  			mlog_errno(ret);
  			return ret;
  		}
  	}
  
  	if (!(s_size + a_size))
  		return ret;
  
  	/*
  	 * The max space of security xattr taken inline is
  	 * 256(name) + 80(value) + 16(entry) = 352 bytes,
  	 * The max space of acl xattr taken inline is
  	 * 80(value) + 16(entry) * 2(if directory) = 192 bytes,
  	 * when blocksize = 512, may reserve one more cluser for
  	 * xattr bucket, otherwise reserve one metadata block
  	 * for them is ok.

  	 * If this is a new directory with inline data,
  	 * we choose to reserve the entire inline area for
  	 * directory contents and force an external xattr block.

  	 */
  	if (dir->i_sb->s_blocksize == OCFS2_MIN_BLOCKSIZE ||

  	    (S_ISDIR(mode) && ocfs2_supports_inline_data(osb)) ||

  	    (s_size + a_size) > OCFS2_XATTR_FREE_IN_IBODY) {

  		*want_meta = *want_meta + 1;

  		*xattr_credits += OCFS2_XATTR_BLOCK_CREATE_CREDITS;
  	}
  
  	if (dir->i_sb->s_blocksize == OCFS2_MIN_BLOCKSIZE &&
  	    (s_size + a_size) > OCFS2_XATTR_FREE_IN_BLOCK(dir)) {
  		*want_clusters += 1;
  		*xattr_credits += ocfs2_blocks_per_xattr_bucket(dir->i_sb);
  	}

  	/*
  	 * reserve credits and clusters for xattrs which has large value
  	 * and have to be set outside
  	 */
  	if (si->enable && si->value_len > OCFS2_XATTR_INLINE_SIZE) {
  		new_clusters = ocfs2_clusters_for_bytes(dir->i_sb,
  							si->value_len);
  		*xattr_credits += ocfs2_clusters_to_blocks(dir->i_sb,
  							   new_clusters);
  		*want_clusters += new_clusters;
  	}

  	if (osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL &&
  	    acl_len > OCFS2_XATTR_INLINE_SIZE) {

  		/* for directory, it has DEFAULT and ACCESS two types of acls */
  		new_clusters = (S_ISDIR(mode) ? 2 : 1) *
  				ocfs2_clusters_for_bytes(dir->i_sb, acl_len);
  		*xattr_credits += ocfs2_clusters_to_blocks(dir->i_sb,
  							   new_clusters);
  		*want_clusters += new_clusters;

  	}
  
  	return ret;
  }

  static int ocfs2_xattr_extend_allocation(struct inode *inode,
  					 u32 clusters_to_add,

  					 struct ocfs2_xattr_value_buf *vb,

  					 struct ocfs2_xattr_set_ctxt *ctxt)

  {

  	int status = 0, credits;

  	handle_t *handle = ctxt->handle;

  	enum ocfs2_alloc_restarted why;

  	u32 prev_clusters, logical_start = le32_to_cpu(vb->vb_xv->xr_clusters);

  	struct ocfs2_extent_tree et;

  	ocfs2_init_xattr_value_extent_tree(&et, INODE_CACHE(inode), vb);

  	while (clusters_to_add) {

  		trace_ocfs2_xattr_extend_allocation(clusters_to_add);

  		status = vb->vb_access(handle, INODE_CACHE(inode), vb->vb_bh,
  				       OCFS2_JOURNAL_ACCESS_WRITE);
  		if (status < 0) {
  			mlog_errno(status);
  			break;
  		}

  		prev_clusters = le32_to_cpu(vb->vb_xv->xr_clusters);
  		status = ocfs2_add_clusters_in_btree(handle,
  						     &et,
  						     &logical_start,
  						     clusters_to_add,
  						     0,
  						     ctxt->data_ac,
  						     ctxt->meta_ac,
  						     &why);
  		if ((status < 0) && (status != -EAGAIN)) {
  			if (status != -ENOSPC)
  				mlog_errno(status);
  			break;
  		}

  		ocfs2_journal_dirty(handle, vb->vb_bh);
  
  		clusters_to_add -= le32_to_cpu(vb->vb_xv->xr_clusters) -
  					 prev_clusters;
  
  		if (why != RESTART_NONE && clusters_to_add) {
  			/*
  			 * We can only fail in case the alloc file doesn't give
  			 * up enough clusters.
  			 */
  			BUG_ON(why == RESTART_META);

  			credits = ocfs2_calc_extend_credits(inode->i_sb,
  							    &vb->vb_xv->xr_list,
  							    clusters_to_add);
  			status = ocfs2_extend_trans(handle, credits);
  			if (status < 0) {
  				status = -ENOMEM;
  				mlog_errno(status);
  				break;
  			}
  		}
  	}

  
  	return status;
  }
  
  static int __ocfs2_remove_xattr_range(struct inode *inode,

  				      struct ocfs2_xattr_value_buf *vb,

  				      u32 cpos, u32 phys_cpos, u32 len,

  				      unsigned int ext_flags,

  				      struct ocfs2_xattr_set_ctxt *ctxt)

  {
  	int ret;
  	u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);

  	handle_t *handle = ctxt->handle;

  	struct ocfs2_extent_tree et;

  	ocfs2_init_xattr_value_extent_tree(&et, INODE_CACHE(inode), vb);

  	ret = vb->vb_access(handle, INODE_CACHE(inode), vb->vb_bh,

  			    OCFS2_JOURNAL_ACCESS_WRITE);

  	if (ret) {
  		mlog_errno(ret);

  		goto out;

  	}

  	ret = ocfs2_remove_extent(handle, &et, cpos, len, ctxt->meta_ac,

  				  &ctxt->dealloc);

  	if (ret) {
  		mlog_errno(ret);

  		goto out;

  	}

  	le32_add_cpu(&vb->vb_xv->xr_clusters, -len);

  	ocfs2_journal_dirty(handle, vb->vb_bh);

  	if (ext_flags & OCFS2_EXT_REFCOUNTED)
  		ret = ocfs2_decrease_refcount(inode, handle,
  					ocfs2_blocks_to_clusters(inode->i_sb,
  								 phys_blkno),
  					len, ctxt->meta_ac, &ctxt->dealloc, 1);
  	else
  		ret = ocfs2_cache_cluster_dealloc(&ctxt->dealloc,
  						  phys_blkno, len);

  	if (ret)
  		mlog_errno(ret);

  out:

  	return ret;
  }
  
  static int ocfs2_xattr_shrink_size(struct inode *inode,
  				   u32 old_clusters,
  				   u32 new_clusters,

  				   struct ocfs2_xattr_value_buf *vb,

  				   struct ocfs2_xattr_set_ctxt *ctxt)

  {
  	int ret = 0;

  	unsigned int ext_flags;

  	u32 trunc_len, cpos, phys_cpos, alloc_size;
  	u64 block;

  
  	if (old_clusters <= new_clusters)
  		return 0;
  
  	cpos = new_clusters;
  	trunc_len = old_clusters - new_clusters;
  	while (trunc_len) {
  		ret = ocfs2_xattr_get_clusters(inode, cpos, &phys_cpos,

  					       &alloc_size,

  					       &vb->vb_xv->xr_list, &ext_flags);

  		if (ret) {
  			mlog_errno(ret);
  			goto out;
  		}
  
  		if (alloc_size > trunc_len)
  			alloc_size = trunc_len;

  		ret = __ocfs2_remove_xattr_range(inode, vb, cpos,

  						 phys_cpos, alloc_size,

  						 ext_flags, ctxt);

  		if (ret) {
  			mlog_errno(ret);
  			goto out;
  		}
  
  		block = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);

  		ocfs2_remove_xattr_clusters_from_cache(INODE_CACHE(inode),
  						       block, alloc_size);

  		cpos += alloc_size;
  		trunc_len -= alloc_size;
  	}
  
  out:

  	return ret;
  }
  
  static int ocfs2_xattr_value_truncate(struct inode *inode,

  				      struct ocfs2_xattr_value_buf *vb,

  				      int len,
  				      struct ocfs2_xattr_set_ctxt *ctxt)

  {
  	int ret;
  	u32 new_clusters = ocfs2_clusters_for_bytes(inode->i_sb, len);

  	u32 old_clusters = le32_to_cpu(vb->vb_xv->xr_clusters);

  
  	if (new_clusters == old_clusters)
  		return 0;
  
  	if (new_clusters > old_clusters)
  		ret = ocfs2_xattr_extend_allocation(inode,
  						    new_clusters - old_clusters,

  						    vb, ctxt);

  	else
  		ret = ocfs2_xattr_shrink_size(inode,
  					      old_clusters, new_clusters,

  					      vb, ctxt);

  
  	return ret;
  }

  static int ocfs2_xattr_list_entry(char *buffer, size_t size,
  				  size_t *result, const char *prefix,
  				  const char *name, int name_len)
  {
  	char *p = buffer + *result;
  	int prefix_len = strlen(prefix);
  	int total_len = prefix_len + name_len + 1;
  
  	*result += total_len;
  
  	/* we are just looking for how big our buffer needs to be */
  	if (!size)
  		return 0;
  
  	if (*result > size)
  		return -ERANGE;
  
  	memcpy(p, prefix, prefix_len);
  	memcpy(p + prefix_len, name, name_len);
  	p[prefix_len + name_len] = '\0';
  
  	return 0;
  }

  static int ocfs2_xattr_list_entries(struct inode *inode,
  				    struct ocfs2_xattr_header *header,
  				    char *buffer, size_t buffer_size)
  {

  	size_t result = 0;
  	int i, type, ret;
  	const char *prefix, *name;

  
  	for (i = 0 ; i < le16_to_cpu(header->xh_count); i++) {
  		struct ocfs2_xattr_entry *entry = &header->xh_entries[i];

  		type = ocfs2_xattr_get_type(entry);
  		prefix = ocfs2_xattr_prefix(type);
  
  		if (prefix) {
  			name = (const char *)header +
  				le16_to_cpu(entry->xe_name_offset);
  
  			ret = ocfs2_xattr_list_entry(buffer, buffer_size,
  						     &result, prefix, name,
  						     entry->xe_name_len);
  			if (ret)
  				return ret;

  		}
  	}

  	return result;

  }

  int ocfs2_has_inline_xattr_value_outside(struct inode *inode,
  					 struct ocfs2_dinode *di)
  {
  	struct ocfs2_xattr_header *xh;
  	int i;
  
  	xh = (struct ocfs2_xattr_header *)
  		 ((void *)di + inode->i_sb->s_blocksize -
  		 le16_to_cpu(di->i_xattr_inline_size));
  
  	for (i = 0; i < le16_to_cpu(xh->xh_count); i++)
  		if (!ocfs2_xattr_is_local(&xh->xh_entries[i]))
  			return 1;
  
  	return 0;
  }

  static int ocfs2_xattr_ibody_list(struct inode *inode,
  				  struct ocfs2_dinode *di,
  				  char *buffer,
  				  size_t buffer_size)
  {
  	struct ocfs2_xattr_header *header = NULL;
  	struct ocfs2_inode_info *oi = OCFS2_I(inode);
  	int ret = 0;
  
  	if (!(oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL))
  		return ret;
  
  	header = (struct ocfs2_xattr_header *)
  		 ((void *)di + inode->i_sb->s_blocksize -
  		 le16_to_cpu(di->i_xattr_inline_size));
  
  	ret = ocfs2_xattr_list_entries(inode, header, buffer, buffer_size);
  
  	return ret;
  }
  
  static int ocfs2_xattr_block_list(struct inode *inode,
  				  struct ocfs2_dinode *di,
  				  char *buffer,
  				  size_t buffer_size)
  {
  	struct buffer_head *blk_bh = NULL;

  	struct ocfs2_xattr_block *xb;

  	int ret = 0;
  
  	if (!di->i_xattr_loc)
  		return ret;

  	ret = ocfs2_read_xattr_block(inode, le64_to_cpu(di->i_xattr_loc),
  				     &blk_bh);

  	if (ret < 0) {
  		mlog_errno(ret);
  		return ret;
  	}

  	xb = (struct ocfs2_xattr_block *)blk_bh->b_data;

  	if (!(le16_to_cpu(xb->xb_flags) & OCFS2_XATTR_INDEXED)) {
  		struct ocfs2_xattr_header *header = &xb->xb_attrs.xb_header;
  		ret = ocfs2_xattr_list_entries(inode, header,
  					       buffer, buffer_size);

  	} else
  		ret = ocfs2_xattr_tree_list_index_block(inode, blk_bh,

  						   buffer, buffer_size);

  	brelse(blk_bh);
  
  	return ret;
  }
  
  ssize_t ocfs2_listxattr(struct dentry *dentry,
  			char *buffer,
  			size_t size)
  {
  	int ret = 0, i_ret = 0, b_ret = 0;
  	struct buffer_head *di_bh = NULL;
  	struct ocfs2_dinode *di = NULL;
  	struct ocfs2_inode_info *oi = OCFS2_I(dentry->d_inode);

  	if (!ocfs2_supports_xattr(OCFS2_SB(dentry->d_sb)))
  		return -EOPNOTSUPP;

  	if (!(oi->ip_dyn_features & OCFS2_HAS_XATTR_FL))
  		return ret;
  
  	ret = ocfs2_inode_lock(dentry->d_inode, &di_bh, 0);
  	if (ret < 0) {
  		mlog_errno(ret);
  		return ret;
  	}
  
  	di = (struct ocfs2_dinode *)di_bh->b_data;
  
  	down_read(&oi->ip_xattr_sem);
  	i_ret = ocfs2_xattr_ibody_list(dentry->d_inode, di, buffer, size);
  	if (i_ret < 0)
  		b_ret = 0;
  	else {
  		if (buffer) {
  			buffer += i_ret;
  			size -= i_ret;
  		}
  		b_ret = ocfs2_xattr_block_list(dentry->d_inode, di,
  					       buffer, size);
  		if (b_ret < 0)
  			i_ret = 0;
  	}
  	up_read(&oi->ip_xattr_sem);
  	ocfs2_inode_unlock(dentry->d_inode, 0);
  
  	brelse(di_bh);
  
  	return i_ret + b_ret;
  }
  
  static int ocfs2_xattr_find_entry(int name_index,
  				  const char *name,
  				  struct ocfs2_xattr_search *xs)
  {
  	struct ocfs2_xattr_entry *entry;
  	size_t name_len;
  	int i, cmp = 1;
  
  	if (name == NULL)
  		return -EINVAL;
  
  	name_len = strlen(name);
  	entry = xs->here;
  	for (i = 0; i < le16_to_cpu(xs->header->xh_count); i++) {
  		cmp = name_index - ocfs2_xattr_get_type(entry);
  		if (!cmp)
  			cmp = name_len - entry->xe_name_len;
  		if (!cmp)
  			cmp = memcmp(name, (xs->base +
  				     le16_to_cpu(entry->xe_name_offset)),
  				     name_len);
  		if (cmp == 0)
  			break;
  		entry += 1;
  	}
  	xs->here = entry;
  
  	return cmp ? -ENODATA : 0;
  }
  
  static int ocfs2_xattr_get_value_outside(struct inode *inode,

  					 struct ocfs2_xattr_value_root *xv,

  					 void *buffer,
  					 size_t len)
  {
  	u32 cpos, p_cluster, num_clusters, bpc, clusters;
  	u64 blkno;
  	int i, ret = 0;
  	size_t cplen, blocksize;
  	struct buffer_head *bh = NULL;

  	struct ocfs2_extent_list *el;

  	el = &xv->xr_list;
  	clusters = le32_to_cpu(xv->xr_clusters);
  	bpc = ocfs2_clusters_to_blocks(inode->i_sb, 1);
  	blocksize = inode->i_sb->s_blocksize;
  
  	cpos = 0;
  	while (cpos < clusters) {
  		ret = ocfs2_xattr_get_clusters(inode, cpos, &p_cluster,

  					       &num_clusters, el, NULL);

  		if (ret) {
  			mlog_errno(ret);
  			goto out;
  		}
  
  		blkno = ocfs2_clusters_to_blocks(inode->i_sb, p_cluster);
  		/* Copy ocfs2_xattr_value */
  		for (i = 0; i < num_clusters * bpc; i++, blkno++) {

  			ret = ocfs2_read_block(INODE_CACHE(inode), blkno,
  					       &bh, NULL);

  			if (ret) {
  				mlog_errno(ret);
  				goto out;
  			}
  
  			cplen = len >= blocksize ? blocksize : len;
  			memcpy(buffer, bh->b_data, cplen);
  			len -= cplen;
  			buffer += cplen;
  
  			brelse(bh);
  			bh = NULL;
  			if (len == 0)
  				break;
  		}
  		cpos += num_clusters;
  	}
  out:
  	return ret;
  }
  
  static int ocfs2_xattr_ibody_get(struct inode *inode,
  				 int name_index,
  				 const char *name,
  				 void *buffer,
  				 size_t buffer_size,
  				 struct ocfs2_xattr_search *xs)
  {
  	struct ocfs2_inode_info *oi = OCFS2_I(inode);
  	struct ocfs2_dinode *di = (struct ocfs2_dinode *)xs->inode_bh->b_data;

  	struct ocfs2_xattr_value_root *xv;

  	size_t size;
  	int ret = 0;
  
  	if (!(oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL))
  		return -ENODATA;
  
  	xs->end = (void *)di + inode->i_sb->s_blocksize;
  	xs->header = (struct ocfs2_xattr_header *)
  			(xs->end - le16_to_cpu(di->i_xattr_inline_size));
  	xs->base = (void *)xs->header;
  	xs->here = xs->header->xh_entries;
  
  	ret = ocfs2_xattr_find_entry(name_index, name, xs);
  	if (ret)
  		return ret;
  	size = le64_to_cpu(xs->here->xe_value_size);
  	if (buffer) {
  		if (size > buffer_size)
  			return -ERANGE;
  		if (ocfs2_xattr_is_local(xs->here)) {
  			memcpy(buffer, (void *)xs->base +
  			       le16_to_cpu(xs->here->xe_name_offset) +
  			       OCFS2_XATTR_SIZE(xs->here->xe_name_len), size);
  		} else {

  			xv = (struct ocfs2_xattr_value_root *)
  				(xs->base + le16_to_cpu(
  				 xs->here->xe_name_offset) +
  				OCFS2_XATTR_SIZE(xs->here->xe_name_len));
  			ret = ocfs2_xattr_get_value_outside(inode, xv,

  							    buffer, size);
  			if (ret < 0) {
  				mlog_errno(ret);
  				return ret;
  			}
  		}
  	}
  
  	return size;
  }
  
  static int ocfs2_xattr_block_get(struct inode *inode,
  				 int name_index,
  				 const char *name,
  				 void *buffer,
  				 size_t buffer_size,
  				 struct ocfs2_xattr_search *xs)
  {

  	struct ocfs2_xattr_block *xb;

  	struct ocfs2_xattr_value_root *xv;

  	size_t size;

  	int ret = -ENODATA, name_offset, name_len, i;
  	int uninitialized_var(block_off);

  	xs->bucket = ocfs2_xattr_bucket_new(inode);
  	if (!xs->bucket) {
  		ret = -ENOMEM;
  		mlog_errno(ret);
  		goto cleanup;
  	}

  	ret = ocfs2_xattr_block_find(inode, name_index, name, xs);
  	if (ret) {

  		mlog_errno(ret);

  		goto cleanup;
  	}

  	if (xs->not_found) {
  		ret = -ENODATA;
  		goto cleanup;
  	}

  	xb = (struct ocfs2_xattr_block *)xs->xattr_bh->b_data;

  	size = le64_to_cpu(xs->here->xe_value_size);
  	if (buffer) {
  		ret = -ERANGE;
  		if (size > buffer_size)
  			goto cleanup;

  
  		name_offset = le16_to_cpu(xs->here->xe_name_offset);
  		name_len = OCFS2_XATTR_SIZE(xs->here->xe_name_len);
  		i = xs->here - xs->header->xh_entries;
  
  		if (le16_to_cpu(xb->xb_flags) & OCFS2_XATTR_INDEXED) {

  			ret = ocfs2_xattr_bucket_get_name_value(inode->i_sb,

  								bucket_xh(xs->bucket),

  								i,
  								&block_off,
  								&name_offset);

  			xs->base = bucket_block(xs->bucket, block_off);

  		}

  		if (ocfs2_xattr_is_local(xs->here)) {
  			memcpy(buffer, (void *)xs->base +

  			       name_offset + name_len, size);

  		} else {

  			xv = (struct ocfs2_xattr_value_root *)
  				(xs->base + name_offset + name_len);
  			ret = ocfs2_xattr_get_value_outside(inode, xv,

  							    buffer, size);
  			if (ret < 0) {
  				mlog_errno(ret);
  				goto cleanup;
  			}
  		}
  	}
  	ret = size;
  cleanup:

  	ocfs2_xattr_bucket_free(xs->bucket);

  	brelse(xs->xattr_bh);
  	xs->xattr_bh = NULL;

  	return ret;
  }

  int ocfs2_xattr_get_nolock(struct inode *inode,
  			   struct buffer_head *di_bh,

  			   int name_index,
  			   const char *name,
  			   void *buffer,
  			   size_t buffer_size)

  {
  	int ret;
  	struct ocfs2_dinode *di = NULL;

  	struct ocfs2_inode_info *oi = OCFS2_I(inode);
  	struct ocfs2_xattr_search xis = {
  		.not_found = -ENODATA,
  	};
  	struct ocfs2_xattr_search xbs = {
  		.not_found = -ENODATA,
  	};

  	if (!ocfs2_supports_xattr(OCFS2_SB(inode->i_sb)))
  		return -EOPNOTSUPP;

  	if (!(oi->ip_dyn_features & OCFS2_HAS_XATTR_FL))
  		ret = -ENODATA;

  	xis.inode_bh = xbs.inode_bh = di_bh;
  	di = (struct ocfs2_dinode *)di_bh->b_data;

  	ret = ocfs2_xattr_ibody_get(inode, name_index, name, buffer,
  				    buffer_size, &xis);

  	if (ret == -ENODATA && di->i_xattr_loc)

  		ret = ocfs2_xattr_block_get(inode, name_index, name, buffer,
  					    buffer_size, &xbs);

  
  	return ret;
  }
  
  /* ocfs2_xattr_get()
   *
   * Copy an extended attribute into the buffer provided.
   * Buffer is NULL to compute the size of buffer required.
   */
  static int ocfs2_xattr_get(struct inode *inode,
  			   int name_index,
  			   const char *name,
  			   void *buffer,
  			   size_t buffer_size)
  {
  	int ret;
  	struct buffer_head *di_bh = NULL;
  
  	ret = ocfs2_inode_lock(inode, &di_bh, 0);
  	if (ret < 0) {
  		mlog_errno(ret);
  		return ret;
  	}

  	down_read(&OCFS2_I(inode)->ip_xattr_sem);

  	ret = ocfs2_xattr_get_nolock(inode, di_bh, name_index,
  				     name, buffer, buffer_size);

  	up_read(&OCFS2_I(inode)->ip_xattr_sem);

  	ocfs2_inode_unlock(inode, 0);
  
  	brelse(di_bh);
  
  	return ret;
  }
  
  static int __ocfs2_xattr_set_value_outside(struct inode *inode,

  					   handle_t *handle,

  					   struct ocfs2_xattr_value_buf *vb,

  					   const void *value,
  					   int value_len)
  {

  	int ret = 0, i, cp_len;

  	u16 blocksize = inode->i_sb->s_blocksize;
  	u32 p_cluster, num_clusters;
  	u32 cpos = 0, bpc = ocfs2_clusters_to_blocks(inode->i_sb, 1);
  	u32 clusters = ocfs2_clusters_for_bytes(inode->i_sb, value_len);
  	u64 blkno;
  	struct buffer_head *bh = NULL;

  	unsigned int ext_flags;
  	struct ocfs2_xattr_value_root *xv = vb->vb_xv;

  
  	BUG_ON(clusters > le32_to_cpu(xv->xr_clusters));

  	while (cpos < clusters) {
  		ret = ocfs2_xattr_get_clusters(inode, cpos, &p_cluster,

  					       &num_clusters, &xv->xr_list,

  					       &ext_flags);

  		if (ret) {
  			mlog_errno(ret);

  			goto out;

  		}

  		BUG_ON(ext_flags & OCFS2_EXT_REFCOUNTED);

  		blkno = ocfs2_clusters_to_blocks(inode->i_sb, p_cluster);
  
  		for (i = 0; i < num_clusters * bpc; i++, blkno++) {

  			ret = ocfs2_read_block(INODE_CACHE(inode), blkno,
  					       &bh, NULL);

  			if (ret) {
  				mlog_errno(ret);

  				goto out;

  			}
  
  			ret = ocfs2_journal_access(handle,

  						   INODE_CACHE(inode),

  						   bh,
  						   OCFS2_JOURNAL_ACCESS_WRITE);
  			if (ret < 0) {
  				mlog_errno(ret);

  				goto out;

  			}
  
  			cp_len = value_len > blocksize ? blocksize : value_len;
  			memcpy(bh->b_data, value, cp_len);
  			value_len -= cp_len;
  			value += cp_len;
  			if (cp_len < blocksize)
  				memset(bh->b_data + cp_len, 0,
  				       blocksize - cp_len);

  			ocfs2_journal_dirty(handle, bh);

  			brelse(bh);
  			bh = NULL;
  
  			/*
  			 * XXX: do we need to empty all the following
  			 * blocks in this cluster?
  			 */
  			if (!value_len)
  				break;
  		}
  		cpos += num_clusters;
  	}

  out:
  	brelse(bh);
  
  	return ret;
  }

  static int ocfs2_xa_check_space_helper(int needed_space, int free_start,
  				       int num_entries)
  {
  	int free_space;
  
  	if (!needed_space)
  		return 0;
  
  	free_space = free_start -
  		sizeof(struct ocfs2_xattr_header) -
  		(num_entries * sizeof(struct ocfs2_xattr_entry)) -
  		OCFS2_XATTR_HEADER_GAP;
  	if (free_space < 0)
  		return -EIO;
  	if (free_space < needed_space)
  		return -ENOSPC;
  
  	return 0;
  }

  static int ocfs2_xa_journal_access(handle_t *handle, struct ocfs2_xa_loc *loc,
  				   int type)
  {
  	return loc->xl_ops->xlo_journal_access(handle, loc, type);
  }
  
  static void ocfs2_xa_journal_dirty(handle_t *handle, struct ocfs2_xa_loc *loc)
  {
  	loc->xl_ops->xlo_journal_dirty(handle, loc);
  }

  /* Give a pointer into the storage for the given offset */
  static void *ocfs2_xa_offset_pointer(struct ocfs2_xa_loc *loc, int offset)
  {
  	BUG_ON(offset >= loc->xl_size);
  	return loc->xl_ops->xlo_offset_pointer(loc, offset);
  }

  /*

   * Wipe the name+value pair and allow the storage to reclaim it.  This
   * must be followed by either removal of the entry or a call to
   * ocfs2_xa_add_namevalue().
   */
  static void ocfs2_xa_wipe_namevalue(struct ocfs2_xa_loc *loc)
  {
  	loc->xl_ops->xlo_wipe_namevalue(loc);
  }

  /*
   * Find lowest offset to a name+value pair.  This is the start of our
   * downward-growing free space.
   */
  static int ocfs2_xa_get_free_start(struct ocfs2_xa_loc *loc)
  {
  	return loc->xl_ops->xlo_get_free_start(loc);
  }
  
  /* Can we reuse loc->xl_entry for xi? */
  static int ocfs2_xa_can_reuse_entry(struct ocfs2_xa_loc *loc,
  				    struct ocfs2_xattr_info *xi)
  {
  	return loc->xl_ops->xlo_can_reuse(loc, xi);
  }
  
  /* How much free space is needed to set the new value */
  static int ocfs2_xa_check_space(struct ocfs2_xa_loc *loc,
  				struct ocfs2_xattr_info *xi)
  {
  	return loc->xl_ops->xlo_check_space(loc, xi);
  }
  
  static void ocfs2_xa_add_entry(struct ocfs2_xa_loc *loc, u32 name_hash)
  {
  	loc->xl_ops->xlo_add_entry(loc, name_hash);
  	loc->xl_entry->xe_name_hash = cpu_to_le32(name_hash);
  	/*
  	 * We can't leave the new entry's xe_name_offset at zero or
  	 * add_namevalue() will go nuts.  We set it to the size of our
  	 * storage so that it can never be less than any other entry.
  	 */
  	loc->xl_entry->xe_name_offset = cpu_to_le16(loc->xl_size);
  }
  
  static void ocfs2_xa_add_namevalue(struct ocfs2_xa_loc *loc,
  				   struct ocfs2_xattr_info *xi)
  {
  	int size = namevalue_size_xi(xi);
  	int nameval_offset;
  	char *nameval_buf;
  
  	loc->xl_ops->xlo_add_namevalue(loc, size);
  	loc->xl_entry->xe_value_size = cpu_to_le64(xi->xi_value_len);
  	loc->xl_entry->xe_name_len = xi->xi_name_len;
  	ocfs2_xattr_set_type(loc->xl_entry, xi->xi_name_index);
  	ocfs2_xattr_set_local(loc->xl_entry,
  			      xi->xi_value_len <= OCFS2_XATTR_INLINE_SIZE);
  
  	nameval_offset = le16_to_cpu(loc->xl_entry->xe_name_offset);
  	nameval_buf = ocfs2_xa_offset_pointer(loc, nameval_offset);
  	memset(nameval_buf, 0, size);
  	memcpy(nameval_buf, xi->xi_name, xi->xi_name_len);
  }

  static void ocfs2_xa_fill_value_buf(struct ocfs2_xa_loc *loc,
  				    struct ocfs2_xattr_value_buf *vb)
  {
  	int nameval_offset = le16_to_cpu(loc->xl_entry->xe_name_offset);
  	int name_size = OCFS2_XATTR_SIZE(loc->xl_entry->xe_name_len);
  
  	/* Value bufs are for value trees */

  	BUG_ON(ocfs2_xattr_is_local(loc->xl_entry));

  	BUG_ON(namevalue_size_xe(loc->xl_entry) !=
  	       (name_size + OCFS2_XATTR_ROOT_SIZE));
  
  	loc->xl_ops->xlo_fill_value_buf(loc, vb);
  	vb->vb_xv =
  		(struct ocfs2_xattr_value_root *)ocfs2_xa_offset_pointer(loc,
  							nameval_offset +
  							name_size);
  }

  static int ocfs2_xa_block_journal_access(handle_t *handle,
  					 struct ocfs2_xa_loc *loc, int type)
  {
  	struct buffer_head *bh = loc->xl_storage;
  	ocfs2_journal_access_func access;
  
  	if (loc->xl_size == (bh->b_size -
  			     offsetof(struct ocfs2_xattr_block,
  				      xb_attrs.xb_header)))
  		access = ocfs2_journal_access_xb;
  	else
  		access = ocfs2_journal_access_di;
  	return access(handle, INODE_CACHE(loc->xl_inode), bh, type);
  }
  
  static void ocfs2_xa_block_journal_dirty(handle_t *handle,
  					 struct ocfs2_xa_loc *loc)
  {
  	struct buffer_head *bh = loc->xl_storage;
  
  	ocfs2_journal_dirty(handle, bh);
  }

  static void *ocfs2_xa_block_offset_pointer(struct ocfs2_xa_loc *loc,
  					   int offset)
  {

  	return (char *)loc->xl_header + offset;
  }

  static int ocfs2_xa_block_can_reuse(struct ocfs2_xa_loc *loc,
  				    struct ocfs2_xattr_info *xi)
  {
  	/*
  	 * Block storage is strict.  If the sizes aren't exact, we will
  	 * remove the old one and reinsert the new.
  	 */
  	return namevalue_size_xe(loc->xl_entry) ==
  		namevalue_size_xi(xi);
  }
  
  static int ocfs2_xa_block_get_free_start(struct ocfs2_xa_loc *loc)
  {
  	struct ocfs2_xattr_header *xh = loc->xl_header;
  	int i, count = le16_to_cpu(xh->xh_count);
  	int offset, free_start = loc->xl_size;
  
  	for (i = 0; i < count; i++) {
  		offset = le16_to_cpu(xh->xh_entries[i].xe_name_offset);
  		if (offset < free_start)
  			free_start = offset;
  	}
  
  	return free_start;
  }
  
  static int ocfs2_xa_block_check_space(struct ocfs2_xa_loc *loc,
  				      struct ocfs2_xattr_info *xi)
  {
  	int count = le16_to_cpu(loc->xl_header->xh_count);
  	int free_start = ocfs2_xa_get_free_start(loc);
  	int needed_space = ocfs2_xi_entry_usage(xi);
  
  	/*
  	 * Block storage will reclaim the original entry before inserting
  	 * the new value, so we only need the difference.  If the new
  	 * entry is smaller than the old one, we don't need anything.
  	 */
  	if (loc->xl_entry) {
  		/* Don't need space if we're reusing! */
  		if (ocfs2_xa_can_reuse_entry(loc, xi))
  			needed_space = 0;
  		else
  			needed_space -= ocfs2_xe_entry_usage(loc->xl_entry);
  	}
  	if (needed_space < 0)
  		needed_space = 0;
  	return ocfs2_xa_check_space_helper(needed_space, free_start, count);
  }

  /*
   * Block storage for xattrs keeps the name+value pairs compacted.  When
   * we remove one, we have to shift any that preceded it towards the end.
   */
  static void ocfs2_xa_block_wipe_namevalue(struct ocfs2_xa_loc *loc)
  {
  	int i, offset;
  	int namevalue_offset, first_namevalue_offset, namevalue_size;
  	struct ocfs2_xattr_entry *entry = loc->xl_entry;
  	struct ocfs2_xattr_header *xh = loc->xl_header;

  	int count = le16_to_cpu(xh->xh_count);
  
  	namevalue_offset = le16_to_cpu(entry->xe_name_offset);

  	namevalue_size = namevalue_size_xe(entry);

  	first_namevalue_offset = ocfs2_xa_get_free_start(loc);

  
  	/* Shift the name+value pairs */
  	memmove((char *)xh + first_namevalue_offset + namevalue_size,
  		(char *)xh + first_namevalue_offset,
  		namevalue_offset - first_namevalue_offset);
  	memset((char *)xh + first_namevalue_offset, 0, namevalue_size);
  
  	/* Now tell xh->xh_entries about it */
  	for (i = 0; i < count; i++) {
  		offset = le16_to_cpu(xh->xh_entries[i].xe_name_offset);

  		if (offset <= namevalue_offset)

  			le16_add_cpu(&xh->xh_entries[i].xe_name_offset,
  				     namevalue_size);
  	}
  
  	/*
  	 * Note that we don't update xh_free_start or xh_name_value_len
  	 * because they're not used in block-stored xattrs.
  	 */
  }

  static void ocfs2_xa_block_add_entry(struct ocfs2_xa_loc *loc, u32 name_hash)
  {
  	int count = le16_to_cpu(loc->xl_header->xh_count);
  	loc->xl_entry = &(loc->xl_header->xh_entries[count]);
  	le16_add_cpu(&loc->xl_header->xh_count, 1);
  	memset(loc->xl_entry, 0, sizeof(struct ocfs2_xattr_entry));
  }
  
  static void ocfs2_xa_block_add_namevalue(struct ocfs2_xa_loc *loc, int size)
  {
  	int free_start = ocfs2_xa_get_free_start(loc);
  
  	loc->xl_entry->xe_name_offset = cpu_to_le16(free_start - size);
  }

  static void ocfs2_xa_block_fill_value_buf(struct ocfs2_xa_loc *loc,
  					  struct ocfs2_xattr_value_buf *vb)
  {
  	struct buffer_head *bh = loc->xl_storage;
  
  	if (loc->xl_size == (bh->b_size -
  			     offsetof(struct ocfs2_xattr_block,
  				      xb_attrs.xb_header)))
  		vb->vb_access = ocfs2_journal_access_xb;
  	else
  		vb->vb_access = ocfs2_journal_access_di;
  	vb->vb_bh = bh;
  }

  /*
   * Operations for xattrs stored in blocks.  This includes inline inode
   * storage and unindexed ocfs2_xattr_blocks.
   */
  static const struct ocfs2_xa_loc_operations ocfs2_xa_block_loc_ops = {

  	.xlo_journal_access	= ocfs2_xa_block_journal_access,
  	.xlo_journal_dirty	= ocfs2_xa_block_journal_dirty,

  	.xlo_offset_pointer	= ocfs2_xa_block_offset_pointer,

  	.xlo_check_space	= ocfs2_xa_block_check_space,
  	.xlo_can_reuse		= ocfs2_xa_block_can_reuse,
  	.xlo_get_free_start	= ocfs2_xa_block_get_free_start,

  	.xlo_wipe_namevalue	= ocfs2_xa_block_wipe_namevalue,

  	.xlo_add_entry		= ocfs2_xa_block_add_entry,
  	.xlo_add_namevalue	= ocfs2_xa_block_add_namevalue,

  	.xlo_fill_value_buf	= ocfs2_xa_block_fill_value_buf,

  };

  static int ocfs2_xa_bucket_journal_access(handle_t *handle,
  					  struct ocfs2_xa_loc *loc, int type)
  {
  	struct ocfs2_xattr_bucket *bucket = loc->xl_storage;
  
  	return ocfs2_xattr_bucket_journal_access(handle, bucket, type);
  }
  
  static void ocfs2_xa_bucket_journal_dirty(handle_t *handle,
  					  struct ocfs2_xa_loc *loc)
  {
  	struct ocfs2_xattr_bucket *bucket = loc->xl_storage;
  
  	ocfs2_xattr_bucket_journal_dirty(handle, bucket);
  }

  static void *ocfs2_xa_bucket_offset_pointer(struct ocfs2_xa_loc *loc,
  					    int offset)
  {
  	struct ocfs2_xattr_bucket *bucket = loc->xl_storage;
  	int block, block_offset;

  	/* The header is at the front of the bucket */

  	block = offset >> loc->xl_inode->i_sb->s_blocksize_bits;
  	block_offset = offset % loc->xl_inode->i_sb->s_blocksize;

  
  	return bucket_block(bucket, block) + block_offset;
  }

  static int ocfs2_xa_bucket_can_reuse(struct ocfs2_xa_loc *loc,
  				     struct ocfs2_xattr_info *xi)
  {
  	return namevalue_size_xe(loc->xl_entry) >=
  		namevalue_size_xi(xi);
  }
  
  static int ocfs2_xa_bucket_get_free_start(struct ocfs2_xa_loc *loc)
  {
  	struct ocfs2_xattr_bucket *bucket = loc->xl_storage;
  	return le16_to_cpu(bucket_xh(bucket)->xh_free_start);
  }
  
  static int ocfs2_bucket_align_free_start(struct super_block *sb,
  					 int free_start, int size)
  {
  	/*
  	 * We need to make sure that the name+value pair fits within
  	 * one block.
  	 */
  	if (((free_start - size) >> sb->s_blocksize_bits) !=
  	    ((free_start - 1) >> sb->s_blocksize_bits))
  		free_start -= free_start % sb->s_blocksize;
  
  	return free_start;
  }
  
  static int ocfs2_xa_bucket_check_space(struct ocfs2_xa_loc *loc,
  				       struct ocfs2_xattr_info *xi)
  {
  	int rc;
  	int count = le16_to_cpu(loc->xl_header->xh_count);
  	int free_start = ocfs2_xa_get_free_start(loc);
  	int needed_space = ocfs2_xi_entry_usage(xi);
  	int size = namevalue_size_xi(xi);

  	struct super_block *sb = loc->xl_inode->i_sb;

  
  	/*
  	 * Bucket storage does not reclaim name+value pairs it cannot
  	 * reuse.  They live as holes until the bucket fills, and then
  	 * the bucket is defragmented.  However, the bucket can reclaim
  	 * the ocfs2_xattr_entry.
  	 */
  	if (loc->xl_entry) {
  		/* Don't need space if we're reusing! */
  		if (ocfs2_xa_can_reuse_entry(loc, xi))
  			needed_space = 0;
  		else
  			needed_space -= sizeof(struct ocfs2_xattr_entry);
  	}
  	BUG_ON(needed_space < 0);
  
  	if (free_start < size) {
  		if (needed_space)
  			return -ENOSPC;
  	} else {
  		/*
  		 * First we check if it would fit in the first place.
  		 * Below, we align the free start to a block.  This may
  		 * slide us below the minimum gap.  By checking unaligned
  		 * first, we avoid that error.
  		 */
  		rc = ocfs2_xa_check_space_helper(needed_space, free_start,
  						 count);
  		if (rc)
  			return rc;
  		free_start = ocfs2_bucket_align_free_start(sb, free_start,
  							   size);
  	}
  	return ocfs2_xa_check_space_helper(needed_space, free_start, count);
  }

  static void ocfs2_xa_bucket_wipe_namevalue(struct ocfs2_xa_loc *loc)
  {

  	le16_add_cpu(&loc->xl_header->xh_name_value_len,
  		     -namevalue_size_xe(loc->xl_entry));

  }

  static void ocfs2_xa_bucket_add_entry(struct ocfs2_xa_loc *loc, u32 name_hash)
  {
  	struct ocfs2_xattr_header *xh = loc->xl_header;
  	int count = le16_to_cpu(xh->xh_count);
  	int low = 0, high = count - 1, tmp;
  	struct ocfs2_xattr_entry *tmp_xe;
  
  	/*
  	 * We keep buckets sorted by name_hash, so we need to find
  	 * our insert place.
  	 */
  	while (low <= high && count) {
  		tmp = (low + high) / 2;
  		tmp_xe = &xh->xh_entries[tmp];
  
  		if (name_hash > le32_to_cpu(tmp_xe->xe_name_hash))
  			low = tmp + 1;
  		else if (name_hash < le32_to_cpu(tmp_xe->xe_name_hash))
  			high = tmp - 1;
  		else {
  			low = tmp;
  			break;
  		}
  	}
  
  	if (low != count)
  		memmove(&xh->xh_entries[low + 1],
  			&xh->xh_entries[low],
  			((count - low) * sizeof(struct ocfs2_xattr_entry)));
  
  	le16_add_cpu(&xh->xh_count, 1);
  	loc->xl_entry = &xh->xh_entries[low];
  	memset(loc->xl_entry, 0, sizeof(struct ocfs2_xattr_entry));
  }
  
  static void ocfs2_xa_bucket_add_namevalue(struct ocfs2_xa_loc *loc, int size)
  {
  	int free_start = ocfs2_xa_get_free_start(loc);
  	struct ocfs2_xattr_header *xh = loc->xl_header;

  	struct super_block *sb = loc->xl_inode->i_sb;

  	int nameval_offset;
  
  	free_start = ocfs2_bucket_align_free_start(sb, free_start, size);
  	nameval_offset = free_start - size;
  	loc->xl_entry->xe_name_offset = cpu_to_le16(nameval_offset);
  	xh->xh_free_start = cpu_to_le16(nameval_offset);
  	le16_add_cpu(&xh->xh_name_value_len, size);
  
  }

  static void ocfs2_xa_bucket_fill_value_buf(struct ocfs2_xa_loc *loc,
  					   struct ocfs2_xattr_value_buf *vb)
  {
  	struct ocfs2_xattr_bucket *bucket = loc->xl_storage;

  	struct super_block *sb = loc->xl_inode->i_sb;

  	int nameval_offset = le16_to_cpu(loc->xl_entry->xe_name_offset);
  	int size = namevalue_size_xe(loc->xl_entry);
  	int block_offset = nameval_offset >> sb->s_blocksize_bits;
  
  	/* Values are not allowed to straddle block boundaries */
  	BUG_ON(block_offset !=
  	       ((nameval_offset + size - 1) >> sb->s_blocksize_bits));
  	/* We expect the bucket to be filled in */
  	BUG_ON(!bucket->bu_bhs[block_offset]);
  
  	vb->vb_access = ocfs2_journal_access;
  	vb->vb_bh = bucket->bu_bhs[block_offset];
  }

  /* Operations for xattrs stored in buckets. */
  static const struct ocfs2_xa_loc_operations ocfs2_xa_bucket_loc_ops = {

  	.xlo_journal_access	= ocfs2_xa_bucket_journal_access,
  	.xlo_journal_dirty	= ocfs2_xa_bucket_journal_dirty,

  	.xlo_offset_pointer	= ocfs2_xa_bucket_offset_pointer,

  	.xlo_check_space	= ocfs2_xa_bucket_check_space,
  	.xlo_can_reuse		= ocfs2_xa_bucket_can_reuse,
  	.xlo_get_free_start	= ocfs2_xa_bucket_get_free_start,

  	.xlo_wipe_namevalue	= ocfs2_xa_bucket_wipe_namevalue,

  	.xlo_add_entry		= ocfs2_xa_bucket_add_entry,
  	.xlo_add_namevalue	= ocfs2_xa_bucket_add_namevalue,

  	.xlo_fill_value_buf	= ocfs2_xa_bucket_fill_value_buf,

  };

  static unsigned int ocfs2_xa_value_clusters(struct ocfs2_xa_loc *loc)
  {
  	struct ocfs2_xattr_value_buf vb;
  
  	if (ocfs2_xattr_is_local(loc->xl_entry))
  		return 0;
  
  	ocfs2_xa_fill_value_buf(loc, &vb);
  	return le32_to_cpu(vb.vb_xv->xr_clusters);
  }

  static int ocfs2_xa_value_truncate(struct ocfs2_xa_loc *loc, u64 bytes,
  				   struct ocfs2_xattr_set_ctxt *ctxt)
  {
  	int trunc_rc, access_rc;
  	struct ocfs2_xattr_value_buf vb;
  
  	ocfs2_xa_fill_value_buf(loc, &vb);
  	trunc_rc = ocfs2_xattr_value_truncate(loc->xl_inode, &vb, bytes,
  					      ctxt);
  
  	/*
  	 * The caller of ocfs2_xa_value_truncate() has already called
  	 * ocfs2_xa_journal_access on the loc.  However, The truncate code
  	 * calls ocfs2_extend_trans().  This may commit the previous
  	 * transaction and open a new one.  If this is a bucket, truncate
  	 * could leave only vb->vb_bh set up for journaling.  Meanwhile,
  	 * the caller is expecting to dirty the entire bucket.  So we must
  	 * reset the journal work.  We do this even if truncate has failed,
  	 * as it could have failed after committing the extend.
  	 */
  	access_rc = ocfs2_xa_journal_access(ctxt->handle, loc,
  					    OCFS2_JOURNAL_ACCESS_WRITE);
  
  	/* Errors in truncate take precedence */
  	return trunc_rc ? trunc_rc : access_rc;
  }

  static void ocfs2_xa_remove_entry(struct ocfs2_xa_loc *loc)
  {

  	int index, count;
  	struct ocfs2_xattr_header *xh = loc->xl_header;
  	struct ocfs2_xattr_entry *entry = loc->xl_entry;

  	ocfs2_xa_wipe_namevalue(loc);

  	loc->xl_entry = NULL;
  
  	le16_add_cpu(&xh->xh_count, -1);
  	count = le16_to_cpu(xh->xh_count);
  
  	/*
  	 * Only zero out the entry if there are more remaining.  This is
  	 * important for an empty bucket, as it keeps track of the
  	 * bucket's hash value.  It doesn't hurt empty block storage.
  	 */
  	if (count) {
  		index = ((char *)entry - (char *)&xh->xh_entries) /
  			sizeof(struct ocfs2_xattr_entry);
  		memmove(&xh->xh_entries[index], &xh->xh_entries[index + 1],
  			(count - index) * sizeof(struct ocfs2_xattr_entry));
  		memset(&xh->xh_entries[count], 0,
  		       sizeof(struct ocfs2_xattr_entry));
  	}

  }

  /*
   * If we have a problem adjusting the size of an external value during
   * ocfs2_xa_prepare_entry() or ocfs2_xa_remove(), we may have an xattr
   * in an intermediate state.  For example, the value may be partially
   * truncated.
   *
   * If the value tree hasn't changed, the extend/truncate went nowhere.
   * We have nothing to do.  The caller can treat it as a straight error.
   *
   * If the value tree got partially truncated, we now have a corrupted
   * extended attribute.  We're going to wipe its entry and leak the
   * clusters.  Better to leak some storage than leave a corrupt entry.
   *
   * If the value tree grew, it obviously didn't grow enough for the
   * new entry.  We're not going to try and reclaim those clusters either.
   * If there was already an external value there (orig_clusters != 0),
   * the new clusters are attached safely and we can just leave the old
   * value in place.  If there was no external value there, we remove
   * the entry.
   *
   * This way, the xattr block we store in the journal will be consistent.
   * If the size change broke because of the journal, no changes will hit
   * disk anyway.
   */
  static void ocfs2_xa_cleanup_value_truncate(struct ocfs2_xa_loc *loc,
  					    const char *what,
  					    unsigned int orig_clusters)
  {
  	unsigned int new_clusters = ocfs2_xa_value_clusters(loc);
  	char *nameval_buf = ocfs2_xa_offset_pointer(loc,
  				le16_to_cpu(loc->xl_entry->xe_name_offset));
  
  	if (new_clusters < orig_clusters) {
  		mlog(ML_ERROR,
  		     "Partial truncate while %s xattr %.*s.  Leaking "
  		     "%u clusters and removing the entry
  ",
  		     what, loc->xl_entry->xe_name_len, nameval_buf,
  		     orig_clusters - new_clusters);
  		ocfs2_xa_remove_entry(loc);
  	} else if (!orig_clusters) {
  		mlog(ML_ERROR,
  		     "Unable to allocate an external value for xattr "
  		     "%.*s safely.  Leaking %u clusters and removing the "
  		     "entry
  ",
  		     loc->xl_entry->xe_name_len, nameval_buf,
  		     new_clusters - orig_clusters);
  		ocfs2_xa_remove_entry(loc);
  	} else if (new_clusters > orig_clusters)
  		mlog(ML_ERROR,
  		     "Unable to grow xattr %.*s safely.  %u new clusters "
  		     "have been added, but the value will not be "
  		     "modified
  ",
  		     loc->xl_entry->xe_name_len, nameval_buf,
  		     new_clusters - orig_clusters);
  }

  static int ocfs2_xa_remove(struct ocfs2_xa_loc *loc,
  			   struct ocfs2_xattr_set_ctxt *ctxt)
  {
  	int rc = 0;

  	unsigned int orig_clusters;

  
  	if (!ocfs2_xattr_is_local(loc->xl_entry)) {

  		orig_clusters = ocfs2_xa_value_clusters(loc);

  		rc = ocfs2_xa_value_truncate(loc, 0, ctxt);
  		if (rc) {
  			mlog_errno(rc);

  			/*
  			 * Since this is remove, we can return 0 if
  			 * ocfs2_xa_cleanup_value_truncate() is going to
  			 * wipe the entry anyway.  So we check the
  			 * cluster count as well.
  			 */
  			if (orig_clusters != ocfs2_xa_value_clusters(loc))
  				rc = 0;
  			ocfs2_xa_cleanup_value_truncate(loc, "removing",
  							orig_clusters);
  			if (rc)
  				goto out;

  		}
  	}
  
  	ocfs2_xa_remove_entry(loc);
  
  out:
  	return rc;
  }
  
  static void ocfs2_xa_install_value_root(struct ocfs2_xa_loc *loc)
  {
  	int name_size = OCFS2_XATTR_SIZE(loc->xl_entry->xe_name_len);
  	char *nameval_buf;
  
  	nameval_buf = ocfs2_xa_offset_pointer(loc,
  				le16_to_cpu(loc->xl_entry->xe_name_offset));
  	memcpy(nameval_buf + name_size, &def_xv, OCFS2_XATTR_ROOT_SIZE);
  }
  
  /*
   * Take an existing entry and make it ready for the new value.  This
   * won't allocate space, but it may free space.  It should be ready for
   * ocfs2_xa_prepare_entry() to finish the work.
   */
  static int ocfs2_xa_reuse_entry(struct ocfs2_xa_loc *loc,
  				struct ocfs2_xattr_info *xi,
  				struct ocfs2_xattr_set_ctxt *ctxt)
  {
  	int rc = 0;
  	int name_size = OCFS2_XATTR_SIZE(xi->xi_name_len);

  	unsigned int orig_clusters;

  	char *nameval_buf;
  	int xe_local = ocfs2_xattr_is_local(loc->xl_entry);
  	int xi_local = xi->xi_value_len <= OCFS2_XATTR_INLINE_SIZE;
  
  	BUG_ON(OCFS2_XATTR_SIZE(loc->xl_entry->xe_name_len) !=
  	       name_size);
  
  	nameval_buf = ocfs2_xa_offset_pointer(loc,
  				le16_to_cpu(loc->xl_entry->xe_name_offset));
  	if (xe_local) {
  		memset(nameval_buf + name_size, 0,
  		       namevalue_size_xe(loc->xl_entry) - name_size);
  		if (!xi_local)
  			ocfs2_xa_install_value_root(loc);
  	} else {

  		orig_clusters = ocfs2_xa_value_clusters(loc);

  		if (xi_local) {
  			rc = ocfs2_xa_value_truncate(loc, 0, ctxt);

  			if (rc < 0)

  				mlog_errno(rc);

  			else
  				memset(nameval_buf + name_size, 0,
  				       namevalue_size_xe(loc->xl_entry) -
  				       name_size);

  		} else if (le64_to_cpu(loc->xl_entry->xe_value_size) >
  			   xi->xi_value_len) {
  			rc = ocfs2_xa_value_truncate(loc, xi->xi_value_len,
  						     ctxt);

  			if (rc < 0)

  				mlog_errno(rc);

  		}
  
  		if (rc) {
  			ocfs2_xa_cleanup_value_truncate(loc, "reusing",
  							orig_clusters);
  			goto out;

  		}
  	}
  
  	loc->xl_entry->xe_value_size = cpu_to_le64(xi->xi_value_len);
  	ocfs2_xattr_set_local(loc->xl_entry, xi_local);
  
  out:
  	return rc;
  }

  /*
   * Prepares loc->xl_entry to receive the new xattr.  This includes
   * properly setting up the name+value pair region.  If loc->xl_entry
   * already exists, it will take care of modifying it appropriately.

   *
   * Note that this modifies the data.  You did journal_access already,
   * right?
   */
  static int ocfs2_xa_prepare_entry(struct ocfs2_xa_loc *loc,
  				  struct ocfs2_xattr_info *xi,

  				  u32 name_hash,
  				  struct ocfs2_xattr_set_ctxt *ctxt)

  {
  	int rc = 0;

  	unsigned int orig_clusters;
  	__le64 orig_value_size = 0;

  	rc = ocfs2_xa_check_space(loc, xi);
  	if (rc)
  		goto out;
  
  	if (loc->xl_entry) {
  		if (ocfs2_xa_can_reuse_entry(loc, xi)) {

  			orig_value_size = loc->xl_entry->xe_value_size;

  			rc = ocfs2_xa_reuse_entry(loc, xi, ctxt);
  			if (rc)
  				goto out;
  			goto alloc_value;

  		}

  		if (!ocfs2_xattr_is_local(loc->xl_entry)) {

  			orig_clusters = ocfs2_xa_value_clusters(loc);

  			rc = ocfs2_xa_value_truncate(loc, 0, ctxt);
  			if (rc) {
  				mlog_errno(rc);

  				ocfs2_xa_cleanup_value_truncate(loc,
  								"overwriting",
  								orig_clusters);

  				goto out;
  			}
  		}

  		ocfs2_xa_wipe_namevalue(loc);
  	} else
  		ocfs2_xa_add_entry(loc, name_hash);
  
  	/*
  	 * If we get here, we have a blank entry.  Fill it.  We grow our
  	 * name+value pair back from the end.
  	 */
  	ocfs2_xa_add_namevalue(loc, xi);

  	if (xi->xi_value_len > OCFS2_XATTR_INLINE_SIZE)
  		ocfs2_xa_install_value_root(loc);
  
  alloc_value:
  	if (xi->xi_value_len > OCFS2_XATTR_INLINE_SIZE) {

  		orig_clusters = ocfs2_xa_value_clusters(loc);

  		rc = ocfs2_xa_value_truncate(loc, xi->xi_value_len, ctxt);

  		if (rc < 0) {

  			ctxt->set_abort = 1;

  			ocfs2_xa_cleanup_value_truncate(loc, "growing",
  							orig_clusters);

  			/*
  			 * If we were growing an existing value,
  			 * ocfs2_xa_cleanup_value_truncate() won't remove
  			 * the entry. We need to restore the original value
  			 * size.
  			 */
  			if (loc->xl_entry) {
  				BUG_ON(!orig_value_size);
  				loc->xl_entry->xe_value_size = orig_value_size;
  			}

  			mlog_errno(rc);

  		}

  	}

  
  out:
  	return rc;
  }
  
  /*

   * Store the value portion of the name+value pair.  This will skip
   * values that are stored externally.  Their tree roots were set up
   * by ocfs2_xa_prepare_entry().

   */

  static int ocfs2_xa_store_value(struct ocfs2_xa_loc *loc,
  				struct ocfs2_xattr_info *xi,
  				struct ocfs2_xattr_set_ctxt *ctxt)

  {

  	int rc = 0;

  	int nameval_offset = le16_to_cpu(loc->xl_entry->xe_name_offset);
  	int name_size = OCFS2_XATTR_SIZE(xi->xi_name_len);

  	char *nameval_buf;

  	struct ocfs2_xattr_value_buf vb;

  	nameval_buf = ocfs2_xa_offset_pointer(loc, nameval_offset);

  	if (xi->xi_value_len > OCFS2_XATTR_INLINE_SIZE) {
  		ocfs2_xa_fill_value_buf(loc, &vb);
  		rc = __ocfs2_xattr_set_value_outside(loc->xl_inode,
  						     ctxt->handle, &vb,
  						     xi->xi_value,
  						     xi->xi_value_len);
  	} else
  		memcpy(nameval_buf + name_size, xi->xi_value, xi->xi_value_len);

  	return rc;

  }

  static int ocfs2_xa_set(struct ocfs2_xa_loc *loc,
  			struct ocfs2_xattr_info *xi,
  			struct ocfs2_xattr_set_ctxt *ctxt)
  {
  	int ret;
  	u32 name_hash = ocfs2_xattr_name_hash(loc->xl_inode, xi->xi_name,
  					      xi->xi_name_len);
  
  	ret = ocfs2_xa_journal_access(ctxt->handle, loc,
  				      OCFS2_JOURNAL_ACCESS_WRITE);
  	if (ret) {
  		mlog_errno(ret);
  		goto out;
  	}

  	/*
  	 * From here on out, everything is going to modify the buffer a
  	 * little.  Errors are going to leave the xattr header in a
  	 * sane state.  Thus, even with errors we dirty the sucker.
  	 */

  	/* Don't worry, we are never called with !xi_value and !xl_entry */
  	if (!xi->xi_value) {
  		ret = ocfs2_xa_remove(loc, ctxt);

  		goto out_dirty;

  	}
  
  	ret = ocfs2_xa_prepare_entry(loc, xi, name_hash, ctxt);
  	if (ret) {
  		if (ret != -ENOSPC)
  			mlog_errno(ret);

  		goto out_dirty;

  	}
  
  	ret = ocfs2_xa_store_value(loc, xi, ctxt);

  	if (ret)

  		mlog_errno(ret);

  out_dirty:

  	ocfs2_xa_journal_dirty(ctxt->handle, loc);
  
  out:
  	return ret;
  }

  static void ocfs2_init_dinode_xa_loc(struct ocfs2_xa_loc *loc,
  				     struct inode *inode,
  				     struct buffer_head *bh,
  				     struct ocfs2_xattr_entry *entry)
  {
  	struct ocfs2_dinode *di = (struct ocfs2_dinode *)bh->b_data;

  	BUG_ON(!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_XATTR_FL));

  	loc->xl_inode = inode;

  	loc->xl_ops = &ocfs2_xa_block_loc_ops;
  	loc->xl_storage = bh;
  	loc->xl_entry = entry;

  	loc->xl_size = le16_to_cpu(di->i_xattr_inline_size);

  	loc->xl_header =
  		(struct ocfs2_xattr_header *)(bh->b_data + bh->b_size -
  					      loc->xl_size);
  }
  
  static void ocfs2_init_xattr_block_xa_loc(struct ocfs2_xa_loc *loc,

  					  struct inode *inode,

  					  struct buffer_head *bh,
  					  struct ocfs2_xattr_entry *entry)
  {
  	struct ocfs2_xattr_block *xb =
  		(struct ocfs2_xattr_block *)bh->b_data;
  
  	BUG_ON(le16_to_cpu(xb->xb_flags) & OCFS2_XATTR_INDEXED);

  	loc->xl_inode = inode;

  	loc->xl_ops = &ocfs2_xa_block_loc_ops;
  	loc->xl_storage = bh;
  	loc->xl_header = &(xb->xb_attrs.xb_header);
  	loc->xl_entry = entry;
  	loc->xl_size = bh->b_size - offsetof(struct ocfs2_xattr_block,
  					     xb_attrs.xb_header);
  }
  
  static void ocfs2_init_xattr_bucket_xa_loc(struct ocfs2_xa_loc *loc,
  					   struct ocfs2_xattr_bucket *bucket,
  					   struct ocfs2_xattr_entry *entry)
  {

  	loc->xl_inode = bucket->bu_inode;

  	loc->xl_ops = &ocfs2_xa_bucket_loc_ops;
  	loc->xl_storage = bucket;
  	loc->xl_header = bucket_xh(bucket);
  	loc->xl_entry = entry;
  	loc->xl_size = OCFS2_XATTR_BUCKET_SIZE;
  }

  /*
   * In xattr remove, if it is stored outside and refcounted, we may have
   * the chance to split the refcount tree. So need the allocators.
   */
  static int ocfs2_lock_xattr_remove_allocators(struct inode *inode,
  					struct ocfs2_xattr_value_root *xv,
  					struct ocfs2_caching_info *ref_ci,
  					struct buffer_head *ref_root_bh,
  					struct ocfs2_alloc_context **meta_ac,
  					int *ref_credits)
  {
  	int ret, meta_add = 0;
  	u32 p_cluster, num_clusters;
  	unsigned int ext_flags;
  
  	*ref_credits = 0;
  	ret = ocfs2_xattr_get_clusters(inode, 0, &p_cluster,
  				       &num_clusters,
  				       &xv->xr_list,
  				       &ext_flags);
  	if (ret) {
  		mlog_errno(ret);
  		goto out;
  	}
  
  	if (!(ext_flags & OCFS2_EXT_REFCOUNTED))
  		goto out;
  
  	ret = ocfs2_refcounted_xattr_delete_need(inode, ref_ci,
  						 ref_root_bh, xv,
  						 &meta_add, ref_credits);
  	if (ret) {
  		mlog_errno(ret);
  		goto out;
  	}
  
  	ret = ocfs2_reserve_new_metadata_blocks(OCFS2_SB(inode->i_sb),
  						meta_add, meta_ac);
  	if (ret)
  		mlog_errno(ret);
  
  out:
  	return ret;
  }

  static int ocfs2_remove_value_outside(struct inode*inode,

  				      struct ocfs2_xattr_value_buf *vb,

  				      struct ocfs2_xattr_header *header,
  				      struct ocfs2_caching_info *ref_ci,
  				      struct buffer_head *ref_root_bh)

  {

  	int ret = 0, i, ref_credits;

  	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  	struct ocfs2_xattr_set_ctxt ctxt = { NULL, NULL, };

  	void *val;

  
  	ocfs2_init_dealloc_ctxt(&ctxt.dealloc);

  
  	for (i = 0; i < le16_to_cpu(header->xh_count); i++) {
  		struct ocfs2_xattr_entry *entry = &header->xh_entries[i];

  		if (ocfs2_xattr_is_local(entry))
  			continue;

  		val = (void *)header +
  			le16_to_cpu(entry->xe_name_offset);
  		vb->vb_xv = (struct ocfs2_xattr_value_root *)
  			(val + OCFS2_XATTR_SIZE(entry->xe_name_len));
  
  		ret = ocfs2_lock_xattr_remove_allocators(inode, vb->vb_xv,
  							 ref_ci, ref_root_bh,
  							 &ctxt.meta_ac,
  							 &ref_credits);
  
  		ctxt.handle = ocfs2_start_trans(osb, ref_credits +
  					ocfs2_remove_extent_credits(osb->sb));
  		if (IS_ERR(ctxt.handle)) {
  			ret = PTR_ERR(ctxt.handle);
  			mlog_errno(ret);
  			break;
  		}
  
  		ret = ocfs2_xattr_value_truncate(inode, vb, 0, &ctxt);

  
  		ocfs2_commit_trans(osb, ctxt.handle);
  		if (ctxt.meta_ac) {
  			ocfs2_free_alloc_context(ctxt.meta_ac);
  			ctxt.meta_ac = NULL;

  		}

  
  		if (ret < 0) {
  			mlog_errno(ret);
  			break;
  		}

  	}

  	if (ctxt.meta_ac)
  		ocfs2_free_alloc_context(ctxt.meta_ac);

  	ocfs2_schedule_truncate_log_flush(osb, 1);
  	ocfs2_run_deallocs(osb, &ctxt.dealloc);

  	return ret;
  }
  
  static int ocfs2_xattr_ibody_remove(struct inode *inode,

  				    struct buffer_head *di_bh,
  				    struct ocfs2_caching_info *ref_ci,
  				    struct buffer_head *ref_root_bh)

  {
  
  	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
  	struct ocfs2_xattr_header *header;
  	int ret;

  	struct ocfs2_xattr_value_buf vb = {
  		.vb_bh = di_bh,
  		.vb_access = ocfs2_journal_access_di,
  	};

  
  	header = (struct ocfs2_xattr_header *)
  		 ((void *)di + inode->i_sb->s_blocksize -
  		 le16_to_cpu(di->i_xattr_inline_size));

  	ret = ocfs2_remove_value_outside(inode, &vb, header,
  					 ref_ci, ref_root_bh);

  
  	return ret;
  }

  struct ocfs2_rm_xattr_bucket_para {
  	struct ocfs2_caching_info *ref_ci;
  	struct buffer_head *ref_root_bh;
  };

  static int ocfs2_xattr_block_remove(struct inode *inode,

  				    struct buffer_head *blk_bh,
  				    struct ocfs2_caching_info *ref_ci,
  				    struct buffer_head *ref_root_bh)

  {
  	struct ocfs2_xattr_block *xb;

  	int ret = 0;

  	struct ocfs2_xattr_value_buf vb = {
  		.vb_bh = blk_bh,
  		.vb_access = ocfs2_journal_access_xb,
  	};

  	struct ocfs2_rm_xattr_bucket_para args = {
  		.ref_ci = ref_ci,
  		.ref_root_bh = ref_root_bh,
  	};

  
  	xb = (struct ocfs2_xattr_block *)blk_bh->b_data;

  	if (!(le16_to_cpu(xb->xb_flags) & OCFS2_XATTR_INDEXED)) {
  		struct ocfs2_xattr_header *header = &(xb->xb_attrs.xb_header);

  		ret = ocfs2_remove_value_outside(inode, &vb, header,
  						 ref_ci, ref_root_bh);

  	} else

  		ret = ocfs2_iterate_xattr_index_block(inode,
  						blk_bh,
  						ocfs2_rm_xattr_cluster,

  						&args);

  
  	return ret;
  }

  static int ocfs2_xattr_free_block(struct inode *inode,

  				  u64 block,
  				  struct ocfs2_caching_info *ref_ci,
  				  struct buffer_head *ref_root_bh)

  {
  	struct inode *xb_alloc_inode;
  	struct buffer_head *xb_alloc_bh = NULL;
  	struct buffer_head *blk_bh = NULL;
  	struct ocfs2_xattr_block *xb;
  	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  	handle_t *handle;
  	int ret = 0;
  	u64 blk, bg_blkno;
  	u16 bit;

  	ret = ocfs2_read_xattr_block(inode, block, &blk_bh);

  	if (ret < 0) {
  		mlog_errno(ret);
  		goto out;
  	}

  	ret = ocfs2_xattr_block_remove(inode, blk_bh, ref_ci, ref_root_bh);

  	if (ret < 0) {
  		mlog_errno(ret);
  		goto out;
  	}

  	xb = (struct ocfs2_xattr_block *)blk_bh->b_data;

  	blk = le64_to_cpu(xb->xb_blkno);
  	bit = le16_to_cpu(xb->xb_suballoc_bit);

  	if (xb->xb_suballoc_loc)
  		bg_blkno = le64_to_cpu(xb->xb_suballoc_loc);
  	else
  		bg_blkno = ocfs2_which_suballoc_group(blk, bit);

  
  	xb_alloc_inode = ocfs2_get_system_file_inode(osb,
  				EXTENT_ALLOC_SYSTEM_INODE,
  				le16_to_cpu(xb->xb_suballoc_slot));
  	if (!xb_alloc_inode) {
  		ret = -ENOMEM;
  		mlog_errno(ret);
  		goto out;
  	}
  	mutex_lock(&xb_alloc_inode->i_mutex);
  
  	ret = ocfs2_inode_lock(xb_alloc_inode, &xb_alloc_bh, 1);
  	if (ret < 0) {
  		mlog_errno(ret);
  		goto out_mutex;
  	}
  
  	handle = ocfs2_start_trans(osb, OCFS2_SUBALLOC_FREE);
  	if (IS_ERR(handle)) {
  		ret = PTR_ERR(handle);
  		mlog_errno(ret);
  		goto out_unlock;
  	}
  
  	ret = ocfs2_free_suballoc_bits(handle, xb_alloc_inode, xb_alloc_bh,
  				       bit, bg_blkno, 1);
  	if (ret < 0)
  		mlog_errno(ret);
  
  	ocfs2_commit_trans(osb, handle);
  out_unlock:
  	ocfs2_inode_unlock(xb_alloc_inode, 1);
  	brelse(xb_alloc_bh);
  out_mutex:
  	mutex_unlock(&xb_alloc_inode->i_mutex);
  	iput(xb_alloc_inode);
  out:
  	brelse(blk_bh);
  	return ret;
  }

  /*
   * ocfs2_xattr_remove()
   *
   * Free extended attribute resources associated with this inode.
   */
  int ocfs2_xattr_remove(struct inode *inode, struct buffer_head *di_bh)
  {

  	struct ocfs2_inode_info *oi = OCFS2_I(inode);
  	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;

  	struct ocfs2_refcount_tree *ref_tree = NULL;
  	struct buffer_head *ref_root_bh = NULL;
  	struct ocfs2_caching_info *ref_ci = NULL;

  	handle_t *handle;
  	int ret;

  	if (!ocfs2_supports_xattr(OCFS2_SB(inode->i_sb)))
  		return 0;

  	if (!(oi->ip_dyn_features & OCFS2_HAS_XATTR_FL))
  		return 0;

  	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL) {
  		ret = ocfs2_lock_refcount_tree(OCFS2_SB(inode->i_sb),
  					       le64_to_cpu(di->i_refcount_loc),
  					       1, &ref_tree, &ref_root_bh);
  		if (ret) {
  			mlog_errno(ret);
  			goto out;
  		}
  		ref_ci = &ref_tree->rf_ci;
  
  	}

  	if (oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL) {

  		ret = ocfs2_xattr_ibody_remove(inode, di_bh,
  					       ref_ci, ref_root_bh);

  		if (ret < 0) {
  			mlog_errno(ret);
  			goto out;
  		}
  	}

  	if (di->i_xattr_loc) {
  		ret = ocfs2_xattr_free_block(inode,

  					     le64_to_cpu(di->i_xattr_loc),
  					     ref_ci, ref_root_bh);

  		if (ret < 0) {
  			mlog_errno(ret);
  			goto out;
  		}
  	}
  
  	handle = ocfs2_start_trans((OCFS2_SB(inode->i_sb)),
  				   OCFS2_INODE_UPDATE_CREDITS);
  	if (IS_ERR(handle)) {
  		ret = PTR_ERR(handle);
  		mlog_errno(ret);
  		goto out;
  	}

  	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,

  				      OCFS2_JOURNAL_ACCESS_WRITE);

  	if (ret) {
  		mlog_errno(ret);
  		goto out_commit;
  	}

  	di->i_xattr_loc = 0;

  
  	spin_lock(&oi->ip_lock);
  	oi->ip_dyn_features &= ~(OCFS2_INLINE_XATTR_FL | OCFS2_HAS_XATTR_FL);
  	di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features);
  	spin_unlock(&oi->ip_lock);

  	ocfs2_journal_dirty(handle, di_bh);

  out_commit:
  	ocfs2_commit_trans(OCFS2_SB(inode->i_sb), handle);
  out:

  	if (ref_tree)
  		ocfs2_unlock_refcount_tree(OCFS2_SB(inode->i_sb), ref_tree, 1);
  	brelse(ref_root_bh);

  	return ret;
  }
  
  static int ocfs2_xattr_has_space_inline(struct inode *inode,
  					struct ocfs2_dinode *di)
  {
  	struct ocfs2_inode_info *oi = OCFS2_I(inode);
  	unsigned int xattrsize = OCFS2_SB(inode->i_sb)->s_xattr_inline_size;
  	int free;
  
  	if (xattrsize < OCFS2_MIN_XATTR_INLINE_SIZE)
  		return 0;
  
  	if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
  		struct ocfs2_inline_data *idata = &di->id2.i_data;
  		free = le16_to_cpu(idata->id_count) - le64_to_cpu(di->i_size);
  	} else if (ocfs2_inode_is_fast_symlink(inode)) {
  		free = ocfs2_fast_symlink_chars(inode->i_sb) -
  			le64_to_cpu(di->i_size);
  	} else {
  		struct ocfs2_extent_list *el = &di->id2.i_list;
  		free = (le16_to_cpu(el->l_count) -
  			le16_to_cpu(el->l_next_free_rec)) *
  			sizeof(struct ocfs2_extent_rec);
  	}
  	if (free >= xattrsize)
  		return 1;
  
  	return 0;
  }
  
  /*
   * ocfs2_xattr_ibody_find()
   *
   * Find extended attribute in inode block and
   * fill search info into struct ocfs2_xattr_search.
   */
  static int ocfs2_xattr_ibody_find(struct inode *inode,
  				  int name_index,
  				  const char *name,
  				  struct ocfs2_xattr_search *xs)
  {
  	struct ocfs2_inode_info *oi = OCFS2_I(inode);
  	struct ocfs2_dinode *di = (struct ocfs2_dinode *)xs->inode_bh->b_data;
  	int ret;
  	int has_space = 0;
  
  	if (inode->i_sb->s_blocksize == OCFS2_MIN_BLOCKSIZE)
  		return 0;
  
  	if (!(oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL)) {
  		down_read(&oi->ip_alloc_sem);
  		has_space = ocfs2_xattr_has_space_inline(inode, di);
  		up_read(&oi->ip_alloc_sem);
  		if (!has_space)
  			return 0;
  	}
  
  	xs->xattr_bh = xs->inode_bh;
  	xs->end = (void *)di + inode->i_sb->s_blocksize;
  	if (oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL)
  		xs->header = (struct ocfs2_xattr_header *)
  			(xs->end - le16_to_cpu(di->i_xattr_inline_size));
  	else
  		xs->header = (struct ocfs2_xattr_header *)
  			(xs->end - OCFS2_SB(inode->i_sb)->s_xattr_inline_size);
  	xs->base = (void *)xs->header;
  	xs->here = xs->header->xh_entries;
  
  	/* Find the named attribute. */
  	if (oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL) {
  		ret = ocfs2_xattr_find_entry(name_index, name, xs);
  		if (ret && ret != -ENODATA)
  			return ret;
  		xs->not_found = ret;
  	}
  
  	return 0;
  }

  static int ocfs2_xattr_ibody_init(struct inode *inode,
  				  struct buffer_head *di_bh,
  				  struct ocfs2_xattr_set_ctxt *ctxt)
  {
  	int ret;
  	struct ocfs2_inode_info *oi = OCFS2_I(inode);
  	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
  	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  	unsigned int xattrsize = osb->s_xattr_inline_size;
  
  	if (!ocfs2_xattr_has_space_inline(inode, di)) {
  		ret = -ENOSPC;
  		goto out;
  	}
  
  	ret = ocfs2_journal_access_di(ctxt->handle, INODE_CACHE(inode), di_bh,
  				      OCFS2_JOURNAL_ACCESS_WRITE);
  	if (ret) {
  		mlog_errno(ret);
  		goto out;
  	}
  
  	/*
  	 * Adjust extent record count or inline data size
  	 * to reserve space for extended attribute.
  	 */
  	if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
  		struct ocfs2_inline_data *idata = &di->id2.i_data;
  		le16_add_cpu(&idata->id_count, -xattrsize);
  	} else if (!(ocfs2_inode_is_fast_symlink(inode))) {
  		struct ocfs2_extent_list *el = &di->id2.i_list;
  		le16_add_cpu(&el->l_count, -(xattrsize /
  					     sizeof(struct ocfs2_extent_rec)));
  	}
  	di->i_xattr_inline_size = cpu_to_le16(xattrsize);
  
  	spin_lock(&oi->ip_lock);
  	oi->ip_dyn_features |= OCFS2_INLINE_XATTR_FL|OCFS2_HAS_XATTR_FL;
  	di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features);
  	spin_unlock(&oi->ip_lock);

  	ocfs2_journal_dirty(ctxt->handle, di_bh);

  
  out:
  	return ret;
  }

  /*
   * ocfs2_xattr_ibody_set()
   *
   * Set, replace or remove an extended attribute into inode block.
   *
   */
  static int ocfs2_xattr_ibody_set(struct inode *inode,
  				 struct ocfs2_xattr_info *xi,

  				 struct ocfs2_xattr_search *xs,
  				 struct ocfs2_xattr_set_ctxt *ctxt)

  {

  	int ret;

  	struct ocfs2_inode_info *oi = OCFS2_I(inode);
  	struct ocfs2_dinode *di = (struct ocfs2_dinode *)xs->inode_bh->b_data;

  	struct ocfs2_xa_loc loc;

  
  	if (inode->i_sb->s_blocksize == OCFS2_MIN_BLOCKSIZE)
  		return -ENOSPC;
  
  	down_write(&oi->ip_alloc_sem);
  	if (!(oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL)) {
  		if (!ocfs2_xattr_has_space_inline(inode, di)) {
  			ret = -ENOSPC;
  			goto out;
  		}
  	}

  	if (!(oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL)) {
  		ret = ocfs2_xattr_ibody_init(inode, xs->inode_bh, ctxt);
  		if (ret) {
  			if (ret != -ENOSPC)
  				mlog_errno(ret);
  			goto out;
  		}
  	}
  
  	ocfs2_init_dinode_xa_loc(&loc, inode, xs->inode_bh,
  				 xs->not_found ? NULL : xs->here);
  	ret = ocfs2_xa_set(&loc, xi, ctxt);
  	if (ret) {
  		if (ret != -ENOSPC)
  			mlog_errno(ret);
  		goto out;
  	}
  	xs->here = loc.xl_entry;

  out:
  	up_write(&oi->ip_alloc_sem);
  
  	return ret;
  }
  
  /*
   * ocfs2_xattr_block_find()
   *
   * Find extended attribute in external block and
   * fill search info into struct ocfs2_xattr_search.
   */
  static int ocfs2_xattr_block_find(struct inode *inode,
  				  int name_index,
  				  const char *name,
  				  struct ocfs2_xattr_search *xs)
  {
  	struct ocfs2_dinode *di = (struct ocfs2_dinode *)xs->inode_bh->b_data;
  	struct buffer_head *blk_bh = NULL;

  	struct ocfs2_xattr_block *xb;

  	int ret = 0;
  
  	if (!di->i_xattr_loc)
  		return ret;

  	ret = ocfs2_read_xattr_block(inode, le64_to_cpu(di->i_xattr_loc),
  				     &blk_bh);

  	if (ret < 0) {
  		mlog_errno(ret);
  		return ret;
  	}

  	xs->xattr_bh = blk_bh;

  	xb = (struct ocfs2_xattr_block *)blk_bh->b_data;

  
  	if (!(le16_to_cpu(xb->xb_flags) & OCFS2_XATTR_INDEXED)) {
  		xs->header = &xb->xb_attrs.xb_header;
  		xs->base = (void *)xs->header;
  		xs->end = (void *)(blk_bh->b_data) + blk_bh->b_size;
  		xs->here = xs->header->xh_entries;
  
  		ret = ocfs2_xattr_find_entry(name_index, name, xs);
  	} else
  		ret = ocfs2_xattr_index_block_find(inode, blk_bh,
  						   name_index,
  						   name, xs);

  	if (ret && ret != -ENODATA) {
  		xs->xattr_bh = NULL;
  		goto cleanup;
  	}
  	xs->not_found = ret;
  	return 0;

  cleanup:
  	brelse(blk_bh);
  
  	return ret;
  }

  static int ocfs2_create_xattr_block(struct inode *inode,

  				    struct buffer_head *inode_bh,

  				    struct ocfs2_xattr_set_ctxt *ctxt,
  				    int indexed,
  				    struct buffer_head **ret_bh)

  {
  	int ret;
  	u16 suballoc_bit_start;
  	u32 num_got;

  	u64 suballoc_loc, first_blkno;

  	struct ocfs2_dinode *di =  (struct ocfs2_dinode *)inode_bh->b_data;

  	struct buffer_head *new_bh = NULL;
  	struct ocfs2_xattr_block *xblk;

  	ret = ocfs2_journal_access_di(ctxt->handle, INODE_CACHE(inode),
  				      inode_bh, OCFS2_JOURNAL_ACCESS_CREATE);

  	if (ret < 0) {
  		mlog_errno(ret);
  		goto end;
  	}

  	ret = ocfs2_claim_metadata(ctxt->handle, ctxt->meta_ac, 1,

  				   &suballoc_loc, &suballoc_bit_start,
  				   &num_got, &first_blkno);

  	if (ret < 0) {
  		mlog_errno(ret);
  		goto end;
  	}
  
  	new_bh = sb_getblk(inode->i_sb, first_blkno);
  	ocfs2_set_new_buffer_uptodate(INODE_CACHE(inode), new_bh);

  	ret = ocfs2_journal_access_xb(ctxt->handle, INODE_CACHE(inode),

  				      new_bh,
  				      OCFS2_JOURNAL_ACCESS_CREATE);
  	if (ret < 0) {
  		mlog_errno(ret);
  		goto end;
  	}
  
  	/* Initialize ocfs2_xattr_block */
  	xblk = (struct ocfs2_xattr_block *)new_bh->b_data;
  	memset(xblk, 0, inode->i_sb->s_blocksize);
  	strcpy((void *)xblk, OCFS2_XATTR_BLOCK_SIGNATURE);

  	xblk->xb_suballoc_slot = cpu_to_le16(ctxt->meta_ac->ac_alloc_slot);

  	xblk->xb_suballoc_loc = cpu_to_le64(suballoc_loc);

  	xblk->xb_suballoc_bit = cpu_to_le16(suballoc_bit_start);

  	xblk->xb_fs_generation =
  		cpu_to_le32(OCFS2_SB(inode->i_sb)->fs_generation);

  	xblk->xb_blkno = cpu_to_le64(first_blkno);

  	if (indexed) {
  		struct ocfs2_xattr_tree_root *xr = &xblk->xb_attrs.xb_root;
  		xr->xt_clusters = cpu_to_le32(1);
  		xr->xt_last_eb_blk = 0;
  		xr->xt_list.l_tree_depth = 0;
  		xr->xt_list.l_count = cpu_to_le16(
  					ocfs2_xattr_recs_per_xb(inode->i_sb));
  		xr->xt_list.l_next_free_rec = cpu_to_le16(1);
  		xblk->xb_flags = cpu_to_le16(OCFS2_XATTR_INDEXED);
  	}

  	ocfs2_journal_dirty(ctxt->handle, new_bh);

  	/* Add it to the inode */

  	di->i_xattr_loc = cpu_to_le64(first_blkno);

  
  	spin_lock(&OCFS2_I(inode)->ip_lock);
  	OCFS2_I(inode)->ip_dyn_features |= OCFS2_HAS_XATTR_FL;
  	di->i_dyn_features = cpu_to_le16(OCFS2_I(inode)->ip_dyn_features);
  	spin_unlock(&OCFS2_I(inode)->ip_lock);
  
  	ocfs2_journal_dirty(ctxt->handle, inode_bh);

  
  	*ret_bh = new_bh;
  	new_bh = NULL;
  
  end:
  	brelse(new_bh);
  	return ret;
  }

  /*
   * ocfs2_xattr_block_set()
   *
   * Set, replace or remove an extended attribute into external block.
   *
   */
  static int ocfs2_xattr_block_set(struct inode *inode,
  				 struct ocfs2_xattr_info *xi,

  				 struct ocfs2_xattr_search *xs,
  				 struct ocfs2_xattr_set_ctxt *ctxt)

  {
  	struct buffer_head *new_bh = NULL;

  	struct ocfs2_xattr_block *xblk = NULL;

  	int ret;

  	struct ocfs2_xa_loc loc;

  
  	if (!xs->xattr_bh) {

  		ret = ocfs2_create_xattr_block(inode, xs->inode_bh, ctxt,
  					       0, &new_bh);

  		if (ret) {

  			mlog_errno(ret);

  			goto end;

  		}

  		xs->xattr_bh = new_bh;

  		xblk = (struct ocfs2_xattr_block *)xs->xattr_bh->b_data;

  		xs->header = &xblk->xb_attrs.xb_header;
  		xs->base = (void *)xs->header;
  		xs->end = (void *)xblk + inode->i_sb->s_blocksize;
  		xs->here = xs->header->xh_entries;

  	} else
  		xblk = (struct ocfs2_xattr_block *)xs->xattr_bh->b_data;
  
  	if (!(le16_to_cpu(xblk->xb_flags) & OCFS2_XATTR_INDEXED)) {

  		ocfs2_init_xattr_block_xa_loc(&loc, inode, xs->xattr_bh,
  					      xs->not_found ? NULL : xs->here);

  		ret = ocfs2_xa_set(&loc, xi, ctxt);
  		if (!ret)
  			xs->here = loc.xl_entry;