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ip_fragment.c

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  • Forked from hardware-enablement / Rockchip upstream enablement efforts / linux
    Source project has a limited visibility.
    xattr.c 194.54 KiB
    /* -*- 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,
    	&posix_acl_access_xattr_handler,
    	&posix_acl_default_xattr_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]
    					= &posix_acl_access_xattr_handler,
    	[OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT]
    					= &posix_acl_default_xattr_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 new)
    {
    	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 = -ENOMEM;
    			mlog_errno(rc);
    			break;
    		}
    
    		if (!ocfs2_buffer_uptodate(INODE_CACHE(bucket->bu_inode),
    					   bucket->bu_bhs[i])) {
    			if (new)
    				ocfs2_set_new_buffer_uptodate(INODE_CACHE(bucket->bu_inode),
    							      bucket->bu_bhs[i]);
    			else {
    				set_buffer_uptodate(bucket->bu_bhs[i]);
    				ocfs2_set_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);
    			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);
    			if (ret) {
    				mlog_errno(ret);
    				goto cleanup;
    			}
    			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))
    		return -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\n",
    		     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\n",
    		     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\n",
    		     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_update_inode_fsync_trans(handle, inode, 0);
    
    	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_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)) {
    		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);
    	if (!new_bh) {
    		ret = -ENOMEM;
    		mlog_errno(ret);
    		goto end;
    	}
    
    	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;
    		else if ((ret != -ENOSPC) || ctxt->set_abort)
    			goto end;
    		else {
    			ret = ocfs2_xattr_create_index_block(inode, xs, ctxt);
    			if (ret)
    				goto end;
    		}
    	}
    
    	if (le16_to_cpu(xblk->xb_flags) & OCFS2_XATTR_INDEXED)
    		ret = ocfs2_xattr_set_entry_index_block(inode, xi, xs, ctxt);
    
    end:
    	return ret;
    }
    
    /* Check whether the new xattr can be inserted into the inode. */
    static int ocfs2_xattr_can_be_in_inode(struct inode *inode,
    				       struct ocfs2_xattr_info *xi,
    				       struct ocfs2_xattr_search *xs)
    {
    	struct ocfs2_xattr_entry *last;
    	int free, i;
    	size_t min_offs = xs->end - xs->base;
    
    	if (!xs->header)
    		return 0;
    
    	last = xs->header->xh_entries;
    
    	for (i = 0; i < le16_to_cpu(xs->header->xh_count); i++) {
    		size_t offs = le16_to_cpu(last->xe_name_offset);
    		if (offs < min_offs)
    			min_offs = offs;
    		last += 1;
    	}
    
    	free = min_offs - ((void *)last - xs->base) - OCFS2_XATTR_HEADER_GAP;
    	if (free < 0)
    		return 0;
    
    	BUG_ON(!xs->not_found);
    
    	if (free >= (sizeof(struct ocfs2_xattr_entry) + namevalue_size_xi(xi)))
    		return 1;
    
    	return 0;
    }
    
    static int ocfs2_calc_xattr_set_need(struct inode *inode,
    				     struct ocfs2_dinode *di,
    				     struct ocfs2_xattr_info *xi,
    				     struct ocfs2_xattr_search *xis,
    				     struct ocfs2_xattr_search *xbs,
    				     int *clusters_need,
    				     int *meta_need,
    				     int *credits_need)
    {
    	int ret = 0, old_in_xb = 0;
    	int clusters_add = 0, meta_add = 0, credits = 0;
    	struct buffer_head *bh = NULL;
    	struct ocfs2_xattr_block *xb = NULL;
    	struct ocfs2_xattr_entry *xe = NULL;
    	struct ocfs2_xattr_value_root *xv = NULL;
    	char *base = NULL;
    	int name_offset, name_len = 0;
    	u32 new_clusters = ocfs2_clusters_for_bytes(inode->i_sb,
    						    xi->xi_value_len);
    	u64 value_size;
    
    	/*
    	 * Calculate the clusters we need to write.
    	 * No matter whether we replace an old one or add a new one,
    	 * we need this for writing.
    	 */
    	if (xi->xi_value_len > OCFS2_XATTR_INLINE_SIZE)
    		credits += new_clusters *
    			   ocfs2_clusters_to_blocks(inode->i_sb, 1);
    
    	if (xis->not_found && xbs->not_found) {
    		credits += ocfs2_blocks_per_xattr_bucket(inode->i_sb);
    
    		if (xi->xi_value_len > OCFS2_XATTR_INLINE_SIZE) {
    			clusters_add += new_clusters;
    			credits += ocfs2_calc_extend_credits(inode->i_sb,
    							&def_xv.xv.xr_list);
    		}
    
    		goto meta_guess;
    	}
    
    	if (!xis->not_found) {
    		xe = xis->here;
    		name_offset = le16_to_cpu(xe->xe_name_offset);
    		name_len = OCFS2_XATTR_SIZE(xe->xe_name_len);
    		base = xis->base;
    		credits += OCFS2_INODE_UPDATE_CREDITS;
    	} else {
    		int i, block_off = 0;
    		xb = (struct ocfs2_xattr_block *)xbs->xattr_bh->b_data;
    		xe = xbs->here;
    		name_offset = le16_to_cpu(xe->xe_name_offset);
    		name_len = OCFS2_XATTR_SIZE(xe->xe_name_len);
    		i = xbs->here - xbs->header->xh_entries;
    		old_in_xb = 1;
    
    		if (le16_to_cpu(xb->xb_flags) & OCFS2_XATTR_INDEXED) {
    			ret = ocfs2_xattr_bucket_get_name_value(inode->i_sb,
    							bucket_xh(xbs->bucket),
    							i, &block_off,
    							&name_offset);
    			base = bucket_block(xbs->bucket, block_off);
    			credits += ocfs2_blocks_per_xattr_bucket(inode->i_sb);
    		} else {
    			base = xbs->base;
    			credits += OCFS2_XATTR_BLOCK_UPDATE_CREDITS;
    		}
    	}
    
    	/*
    	 * delete a xattr doesn't need metadata and cluster allocation.
    	 * so just calculate the credits and return.
    	 *
    	 * The credits for removing the value tree will be extended
    	 * by ocfs2_remove_extent itself.
    	 */
    	if (!xi->xi_value) {
    		if (!ocfs2_xattr_is_local(xe))
    			credits += ocfs2_remove_extent_credits(inode->i_sb);
    
    		goto out;
    	}
    
    	/* do cluster allocation guess first. */
    	value_size = le64_to_cpu(xe->xe_value_size);
    
    	if (old_in_xb) {
    		/*
    		 * In xattr set, we always try to set the xe in inode first,
    		 * so if it can be inserted into inode successfully, the old
    		 * one will be removed from the xattr block, and this xattr
    		 * will be inserted into inode as a new xattr in inode.
    		 */
    		if (ocfs2_xattr_can_be_in_inode(inode, xi, xis)) {
    			clusters_add += new_clusters;
    			credits += ocfs2_remove_extent_credits(inode->i_sb) +
    				    OCFS2_INODE_UPDATE_CREDITS;
    			if (!ocfs2_xattr_is_local(xe))
    				credits += ocfs2_calc_extend_credits(
    							inode->i_sb,
    							&def_xv.xv.xr_list);
    			goto out;
    		}
    	}
    
    	if (xi->xi_value_len > OCFS2_XATTR_INLINE_SIZE) {
    		/* the new values will be stored outside. */
    		u32 old_clusters = 0;
    
    		if (!ocfs2_xattr_is_local(xe)) {
    			old_clusters =	ocfs2_clusters_for_bytes(inode->i_sb,
    								 value_size);
    			xv = (struct ocfs2_xattr_value_root *)
    			     (base + name_offset + name_len);
    			value_size = OCFS2_XATTR_ROOT_SIZE;
    		} else
    			xv = &def_xv.xv;
    
    		if (old_clusters >= new_clusters) {
    			credits += ocfs2_remove_extent_credits(inode->i_sb);
    			goto out;
    		} else {
    			meta_add += ocfs2_extend_meta_needed(&xv->xr_list);
    			clusters_add += new_clusters - old_clusters;
    			credits += ocfs2_calc_extend_credits(inode->i_sb,
    							     &xv->xr_list);
    			if (value_size >= OCFS2_XATTR_ROOT_SIZE)
    				goto out;
    		}
    	} else {
    		/*
    		 * Now the new value will be stored inside. So if the new
    		 * value is smaller than the size of value root or the old
    		 * value, we don't need any allocation, otherwise we have
    		 * to guess metadata allocation.
    		 */
    		if ((ocfs2_xattr_is_local(xe) &&
    		     (value_size >= xi->xi_value_len)) ||
    		    (!ocfs2_xattr_is_local(xe) &&
    		     OCFS2_XATTR_ROOT_SIZE >= xi->xi_value_len))
    			goto out;
    	}
    
    meta_guess:
    	/* calculate metadata allocation. */
    	if (di->i_xattr_loc) {
    		if (!xbs->xattr_bh) {
    			ret = ocfs2_read_xattr_block(inode,
    						     le64_to_cpu(di->i_xattr_loc),
    						     &bh);
    			if (ret) {
    				mlog_errno(ret);
    				goto out;
    			}
    
    			xb = (struct ocfs2_xattr_block *)bh->b_data;
    		} else
    			xb = (struct ocfs2_xattr_block *)xbs->xattr_bh->b_data;
    
    		/*
    		 * If there is already an xattr tree, good, we can calculate
    		 * like other b-trees. Otherwise we may have the chance of
    		 * create a tree, the credit calculation is borrowed from
    		 * ocfs2_calc_extend_credits with root_el = NULL. And the
    		 * new tree will be cluster based, so no meta is needed.
    		 */
    		if (le16_to_cpu(xb->xb_flags) & OCFS2_XATTR_INDEXED) {
    			struct ocfs2_extent_list *el =
    				 &xb->xb_attrs.xb_root.xt_list;
    			meta_add += ocfs2_extend_meta_needed(el);
    			credits += ocfs2_calc_extend_credits(inode->i_sb,
    							     el);
    		} else
    			credits += OCFS2_SUBALLOC_ALLOC + 1;
    
    		/*
    		 * This cluster will be used either for new bucket or for
    		 * new xattr block.
    		 * If the cluster size is the same as the bucket size, one
    		 * more is needed since we may need to extend the bucket
    		 * also.
    		 */
    		clusters_add += 1;
    		credits += ocfs2_blocks_per_xattr_bucket(inode->i_sb);
    		if (OCFS2_XATTR_BUCKET_SIZE ==
    			OCFS2_SB(inode->i_sb)->s_clustersize) {
    			credits += ocfs2_blocks_per_xattr_bucket(inode->i_sb);
    			clusters_add += 1;
    		}
    	} else {
    		credits += OCFS2_XATTR_BLOCK_CREATE_CREDITS;
    		if (xi->xi_value_len > OCFS2_XATTR_INLINE_SIZE) {
    			struct ocfs2_extent_list *el = &def_xv.xv.xr_list;
    			meta_add += ocfs2_extend_meta_needed(el);
    			credits += ocfs2_calc_extend_credits(inode->i_sb,
    							     el);
    		} else {
    			meta_add += 1;
    		}
    	}
    out:
    	if (clusters_need)
    		*clusters_need = clusters_add;
    	if (meta_need)
    		*meta_need = meta_add;
    	if (credits_need)
    		*credits_need = credits;
    	brelse(bh);
    	return ret;
    }
    
    static int ocfs2_init_xattr_set_ctxt(struct inode *inode,
    				     struct ocfs2_dinode *di,
    				     struct ocfs2_xattr_info *xi,
    				     struct ocfs2_xattr_search *xis,
    				     struct ocfs2_xattr_search *xbs,
    				     struct ocfs2_xattr_set_ctxt *ctxt,
    				     int extra_meta,
    				     int *credits)
    {
    	int clusters_add, meta_add, ret;
    	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
    
    	memset(ctxt, 0, sizeof(struct ocfs2_xattr_set_ctxt));
    
    	ocfs2_init_dealloc_ctxt(&ctxt->dealloc);
    
    	ret = ocfs2_calc_xattr_set_need(inode, di, xi, xis, xbs,
    					&clusters_add, &meta_add, credits);
    	if (ret) {
    		mlog_errno(ret);
    		return ret;
    	}
    
    	meta_add += extra_meta;
    	trace_ocfs2_init_xattr_set_ctxt(xi->xi_name, meta_add,
    					clusters_add, *credits);
    
    	if (meta_add) {
    		ret = ocfs2_reserve_new_metadata_blocks(osb, meta_add,
    							&ctxt->meta_ac);
    		if (ret) {
    			mlog_errno(ret);
    			goto out;
    		}
    	}
    
    	if (clusters_add) {
    		ret = ocfs2_reserve_clusters(osb, clusters_add, &ctxt->data_ac);
    		if (ret)
    			mlog_errno(ret);
    	}
    out:
    	if (ret) {
    		if (ctxt->meta_ac) {
    			ocfs2_free_alloc_context(ctxt->meta_ac);
    			ctxt->meta_ac = NULL;
    		}
    
    		/*
    		 * We cannot have an error and a non null ctxt->data_ac.
    		 */
    	}
    
    	return ret;
    }
    
    static int __ocfs2_xattr_set_handle(struct inode *inode,
    				    struct ocfs2_dinode *di,
    				    struct ocfs2_xattr_info *xi,
    				    struct ocfs2_xattr_search *xis,
    				    struct ocfs2_xattr_search *xbs,
    				    struct ocfs2_xattr_set_ctxt *ctxt)
    {
    	int ret = 0, credits, old_found;
    
    	if (!xi->xi_value) {
    		/* Remove existing extended attribute */
    		if (!xis->not_found)
    			ret = ocfs2_xattr_ibody_set(inode, xi, xis, ctxt);
    		else if (!xbs->not_found)
    			ret = ocfs2_xattr_block_set(inode, xi, xbs, ctxt);
    	} else {
    		/* We always try to set extended attribute into inode first*/
    		ret = ocfs2_xattr_ibody_set(inode, xi, xis, ctxt);
    		if (!ret && !xbs->not_found) {
    			/*
    			 * If succeed and that extended attribute existing in
    			 * external block, then we will remove it.
    			 */
    			xi->xi_value = NULL;
    			xi->xi_value_len = 0;
    
    			old_found = xis->not_found;
    			xis->not_found = -ENODATA;
    			ret = ocfs2_calc_xattr_set_need(inode,
    							di,
    							xi,
    							xis,
    							xbs,
    							NULL,
    							NULL,
    							&credits);
    			xis->not_found = old_found;
    			if (ret) {
    				mlog_errno(ret);
    				goto out;
    			}
    
    			ret = ocfs2_extend_trans(ctxt->handle, credits);
    			if (ret) {
    				mlog_errno(ret);
    				goto out;
    			}
    			ret = ocfs2_xattr_block_set(inode, xi, xbs, ctxt);
    		} else if ((ret == -ENOSPC) && !ctxt->set_abort) {
    			if (di->i_xattr_loc && !xbs->xattr_bh) {
    				ret = ocfs2_xattr_block_find(inode,
    							     xi->xi_name_index,
    							     xi->xi_name, xbs);
    				if (ret)
    					goto out;
    
    				old_found = xis->not_found;
    				xis->not_found = -ENODATA;
    				ret = ocfs2_calc_xattr_set_need(inode,
    								di,
    								xi,
    								xis,
    								xbs,
    								NULL,
    								NULL,
    								&credits);
    				xis->not_found = old_found;
    				if (ret) {
    					mlog_errno(ret);
    					goto out;
    				}
    
    				ret = ocfs2_extend_trans(ctxt->handle, credits);
    				if (ret) {
    					mlog_errno(ret);
    					goto out;
    				}
    			}
    			/*
    			 * If no space in inode, we will set extended attribute
    			 * into external block.
    			 */
    			ret = ocfs2_xattr_block_set(inode, xi, xbs, ctxt);
    			if (ret)
    				goto out;
    			if (!xis->not_found) {
    				/*
    				 * If succeed and that extended attribute
    				 * existing in inode, we will remove it.
    				 */
    				xi->xi_value = NULL;
    				xi->xi_value_len = 0;
    				xbs->not_found = -ENODATA;
    				ret = ocfs2_calc_xattr_set_need(inode,
    								di,
    								xi,
    								xis,
    								xbs,
    								NULL,
    								NULL,
    								&credits);
    				if (ret) {
    					mlog_errno(ret);
    					goto out;
    				}
    
    				ret = ocfs2_extend_trans(ctxt->handle, credits);
    				if (ret) {
    					mlog_errno(ret);
    					goto out;
    				}
    				ret = ocfs2_xattr_ibody_set(inode, xi,
    							    xis, ctxt);
    			}
    		}
    	}
    
    	if (!ret) {
    		/* Update inode ctime. */
    		ret = ocfs2_journal_access_di(ctxt->handle, INODE_CACHE(inode),
    					      xis->inode_bh,
    					      OCFS2_JOURNAL_ACCESS_WRITE);
    		if (ret) {
    			mlog_errno(ret);
    			goto out;
    		}
    
    		inode->i_ctime = CURRENT_TIME;
    		di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
    		di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
    		ocfs2_journal_dirty(ctxt->handle, xis->inode_bh);
    	}
    out:
    	return ret;
    }
    
    /*
     * This function only called duing creating inode
     * for init security/acl xattrs of the new inode.
     * All transanction credits have been reserved in mknod.
     */
    int ocfs2_xattr_set_handle(handle_t *handle,
    			   struct inode *inode,
    			   struct buffer_head *di_bh,
    			   int name_index,
    			   const char *name,
    			   const void *value,
    			   size_t value_len,
    			   int flags,
    			   struct ocfs2_alloc_context *meta_ac,
    			   struct ocfs2_alloc_context *data_ac)
    {
    	struct ocfs2_dinode *di;
    	int ret;
    
    	struct ocfs2_xattr_info xi = {
    		.xi_name_index = name_index,
    		.xi_name = name,
    		.xi_name_len = strlen(name),
    		.xi_value = value,
    		.xi_value_len = value_len,
    	};
    
    	struct ocfs2_xattr_search xis = {
    		.not_found = -ENODATA,
    	};
    
    	struct ocfs2_xattr_search xbs = {
    		.not_found = -ENODATA,
    	};
    
    	struct ocfs2_xattr_set_ctxt ctxt = {
    		.handle = handle,
    		.meta_ac = meta_ac,
    		.data_ac = data_ac,
    	};
    
    	if (!ocfs2_supports_xattr(OCFS2_SB(inode->i_sb)))
    		return -EOPNOTSUPP;
    
    	/*
    	 * In extreme situation, may need xattr bucket when
    	 * block size is too small. And we have already reserved
    	 * the credits for bucket in mknod.
    	 */
    	if (inode->i_sb->s_blocksize == OCFS2_MIN_BLOCKSIZE) {
    		xbs.bucket = ocfs2_xattr_bucket_new(inode);
    		if (!xbs.bucket) {
    			mlog_errno(-ENOMEM);
    			return -ENOMEM;
    		}
    	}
    
    	xis.inode_bh = xbs.inode_bh = di_bh;
    	di = (struct ocfs2_dinode *)di_bh->b_data;
    
    	down_write(&OCFS2_I(inode)->ip_xattr_sem);
    
    	ret = ocfs2_xattr_ibody_find(inode, name_index, name, &xis);
    	if (ret)
    		goto cleanup;
    	if (xis.not_found) {
    		ret = ocfs2_xattr_block_find(inode, name_index, name, &xbs);
    		if (ret)
    			goto cleanup;
    	}
    
    	ret = __ocfs2_xattr_set_handle(inode, di, &xi, &xis, &xbs, &ctxt);
    
    cleanup:
    	up_write(&OCFS2_I(inode)->ip_xattr_sem);
    	brelse(xbs.xattr_bh);
    	ocfs2_xattr_bucket_free(xbs.bucket);
    
    	return ret;
    }
    
    /*
     * ocfs2_xattr_set()
     *
     * Set, replace or remove an extended attribute for this inode.
     * value is NULL to remove an existing extended attribute, else either
     * create or replace an extended attribute.
     */
    int ocfs2_xattr_set(struct inode *inode,
    		    int name_index,
    		    const char *name,
    		    const void *value,
    		    size_t value_len,
    		    int flags)
    {
    	struct buffer_head *di_bh = NULL;
    	struct ocfs2_dinode *di;
    	int ret, credits, ref_meta = 0, ref_credits = 0;
    	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
    	struct inode *tl_inode = osb->osb_tl_inode;
    	struct ocfs2_xattr_set_ctxt ctxt = { NULL, NULL, NULL, };
    	struct ocfs2_refcount_tree *ref_tree = NULL;
    
    	struct ocfs2_xattr_info xi = {
    		.xi_name_index = name_index,
    		.xi_name = name,
    		.xi_name_len = strlen(name),
    		.xi_value = value,
    		.xi_value_len = value_len,
    	};
    
    	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;
    
    	/*
    	 * Only xbs will be used on indexed trees.  xis doesn't need a
    	 * bucket.
    	 */
    	xbs.bucket = ocfs2_xattr_bucket_new(inode);
    	if (!xbs.bucket) {
    		mlog_errno(-ENOMEM);
    		return -ENOMEM;
    	}
    
    	ret = ocfs2_inode_lock(inode, &di_bh, 1);
    	if (ret < 0) {
    		mlog_errno(ret);
    		goto cleanup_nolock;
    	}
    	xis.inode_bh = xbs.inode_bh = di_bh;
    	di = (struct ocfs2_dinode *)di_bh->b_data;
    
    	down_write(&OCFS2_I(inode)->ip_xattr_sem);
    	/*
    	 * Scan inode and external block to find the same name
    	 * extended attribute and collect search information.
    	 */
    	ret = ocfs2_xattr_ibody_find(inode, name_index, name, &xis);
    	if (ret)
    		goto cleanup;
    	if (xis.not_found) {
    		ret = ocfs2_xattr_block_find(inode, name_index, name, &xbs);
    		if (ret)
    			goto cleanup;
    	}
    
    	if (xis.not_found && xbs.not_found) {
    		ret = -ENODATA;
    		if (flags & XATTR_REPLACE)
    			goto cleanup;
    		ret = 0;
    		if (!value)
    			goto cleanup;
    	} else {
    		ret = -EEXIST;
    		if (flags & XATTR_CREATE)
    			goto cleanup;
    	}
    
    	/* Check whether the value is refcounted and do some preparation. */
    	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL &&
    	    (!xis.not_found || !xbs.not_found)) {
    		ret = ocfs2_prepare_refcount_xattr(inode, di, &xi,
    						   &xis, &xbs, &ref_tree,
    						   &ref_meta, &ref_credits);
    		if (ret) {
    			mlog_errno(ret);
    			goto cleanup;
    		}
    	}
    
    	mutex_lock(&tl_inode->i_mutex);
    
    	if (ocfs2_truncate_log_needs_flush(osb)) {
    		ret = __ocfs2_flush_truncate_log(osb);
    		if (ret < 0) {
    			mutex_unlock(&tl_inode->i_mutex);
    			mlog_errno(ret);
    			goto cleanup;
    		}
    	}
    	mutex_unlock(&tl_inode->i_mutex);
    
    	ret = ocfs2_init_xattr_set_ctxt(inode, di, &xi, &xis,
    					&xbs, &ctxt, ref_meta, &credits);
    	if (ret) {
    		mlog_errno(ret);
    		goto cleanup;
    	}
    
    	/* we need to update inode's ctime field, so add credit for it. */
    	credits += OCFS2_INODE_UPDATE_CREDITS;
    	ctxt.handle = ocfs2_start_trans(osb, credits + ref_credits);
    	if (IS_ERR(ctxt.handle)) {
    		ret = PTR_ERR(ctxt.handle);
    		mlog_errno(ret);
    		goto out_free_ac;
    	}
    
    	ret = __ocfs2_xattr_set_handle(inode, di, &xi, &xis, &xbs, &ctxt);
    	ocfs2_update_inode_fsync_trans(ctxt.handle, inode, 0);
    
    	ocfs2_commit_trans(osb, ctxt.handle);
    
    out_free_ac:
    	if (ctxt.data_ac)
    		ocfs2_free_alloc_context(ctxt.data_ac);
    	if (ctxt.meta_ac)
    		ocfs2_free_alloc_context(ctxt.meta_ac);
    	if (ocfs2_dealloc_has_cluster(&ctxt.dealloc))
    		ocfs2_schedule_truncate_log_flush(osb, 1);
    	ocfs2_run_deallocs(osb, &ctxt.dealloc);
    
    cleanup:
    	if (ref_tree)
    		ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
    	up_write(&OCFS2_I(inode)->ip_xattr_sem);
    	if (!value && !ret) {
    		ret = ocfs2_try_remove_refcount_tree(inode, di_bh);
    		if (ret)
    			mlog_errno(ret);
    	}
    	ocfs2_inode_unlock(inode, 1);
    cleanup_nolock:
    	brelse(di_bh);
    	brelse(xbs.xattr_bh);
    	ocfs2_xattr_bucket_free(xbs.bucket);
    
    	return ret;
    }
    
    /*
     * Find the xattr extent rec which may contains name_hash.
     * e_cpos will be the first name hash of the xattr rec.
     * el must be the ocfs2_xattr_header.xb_attrs.xb_root.xt_list.
     */
    static int ocfs2_xattr_get_rec(struct inode *inode,
    			       u32 name_hash,
    			       u64 *p_blkno,
    			       u32 *e_cpos,
    			       u32 *num_clusters,
    			       struct ocfs2_extent_list *el)
    {
    	int ret = 0, i;
    	struct buffer_head *eb_bh = NULL;
    	struct ocfs2_extent_block *eb;
    	struct ocfs2_extent_rec *rec = NULL;
    	u64 e_blkno = 0;
    
    	if (el->l_tree_depth) {
    		ret = ocfs2_find_leaf(INODE_CACHE(inode), el, name_hash,
    				      &eb_bh);
    		if (ret) {
    			mlog_errno(ret);
    			goto out;
    		}
    
    		eb = (struct ocfs2_extent_block *) eb_bh->b_data;
    		el = &eb->h_list;
    
    		if (el->l_tree_depth) {
    			ocfs2_error(inode->i_sb,
    				    "Inode %lu has non zero tree depth in "
    				    "xattr tree block %llu\n", inode->i_ino,
    				    (unsigned long long)eb_bh->b_blocknr);
    			ret = -EROFS;
    			goto out;
    		}
    	}
    
    	for (i = le16_to_cpu(el->l_next_free_rec) - 1; i >= 0; i--) {
    		rec = &el->l_recs[i];
    
    		if (le32_to_cpu(rec->e_cpos) <= name_hash) {
    			e_blkno = le64_to_cpu(rec->e_blkno);
    			break;
    		}
    	}
    
    	if (!e_blkno) {
    		ocfs2_error(inode->i_sb, "Inode %lu has bad extent "
    			    "record (%u, %u, 0) in xattr", inode->i_ino,
    			    le32_to_cpu(rec->e_cpos),
    			    ocfs2_rec_clusters(el, rec));
    		ret = -EROFS;
    		goto out;
    	}
    
    	*p_blkno = le64_to_cpu(rec->e_blkno);
    	*num_clusters = le16_to_cpu(rec->e_leaf_clusters);
    	if (e_cpos)
    		*e_cpos = le32_to_cpu(rec->e_cpos);
    out:
    	brelse(eb_bh);
    	return ret;
    }
    
    typedef int (xattr_bucket_func)(struct inode *inode,
    				struct ocfs2_xattr_bucket *bucket,
    				void *para);
    
    static int ocfs2_find_xe_in_bucket(struct inode *inode,
    				   struct ocfs2_xattr_bucket *bucket,
    				   int name_index,
    				   const char *name,
    				   u32 name_hash,
    				   u16 *xe_index,
    				   int *found)
    {
    	int i, ret = 0, cmp = 1, block_off, new_offset;
    	struct ocfs2_xattr_header *xh = bucket_xh(bucket);
    	size_t name_len = strlen(name);
    	struct ocfs2_xattr_entry *xe = NULL;
    	char *xe_name;
    
    	/*
    	 * We don't use binary search in the bucket because there
    	 * may be multiple entries with the same name hash.
    	 */
    	for (i = 0; i < le16_to_cpu(xh->xh_count); i++) {
    		xe = &xh->xh_entries[i];
    
    		if (name_hash > le32_to_cpu(xe->xe_name_hash))
    			continue;
    		else if (name_hash < le32_to_cpu(xe->xe_name_hash))
    			break;
    
    		cmp = name_index - ocfs2_xattr_get_type(xe);
    		if (!cmp)
    			cmp = name_len - xe->xe_name_len;
    		if (cmp)
    			continue;
    
    		ret = ocfs2_xattr_bucket_get_name_value(inode->i_sb,
    							xh,
    							i,
    							&block_off,
    							&new_offset);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    
    		xe_name = bucket_block(bucket, block_off) + new_offset;
    		if (!memcmp(name, xe_name, name_len)) {
    			*xe_index = i;
    			*found = 1;
    			ret = 0;
    			break;
    		}
    	}
    
    	return ret;
    }
    
    /*
     * Find the specified xattr entry in a series of buckets.
     * This series start from p_blkno and last for num_clusters.
     * The ocfs2_xattr_header.xh_num_buckets of the first bucket contains
     * the num of the valid buckets.
     *
     * Return the buffer_head this xattr should reside in. And if the xattr's
     * hash is in the gap of 2 buckets, return the lower bucket.
     */
    static int ocfs2_xattr_bucket_find(struct inode *inode,
    				   int name_index,
    				   const char *name,
    				   u32 name_hash,
    				   u64 p_blkno,
    				   u32 first_hash,
    				   u32 num_clusters,
    				   struct ocfs2_xattr_search *xs)
    {
    	int ret, found = 0;
    	struct ocfs2_xattr_header *xh = NULL;
    	struct ocfs2_xattr_entry *xe = NULL;
    	u16 index = 0;
    	u16 blk_per_bucket = ocfs2_blocks_per_xattr_bucket(inode->i_sb);
    	int low_bucket = 0, bucket, high_bucket;
    	struct ocfs2_xattr_bucket *search;
    	u32 last_hash;
    	u64 blkno, lower_blkno = 0;
    
    	search = ocfs2_xattr_bucket_new(inode);
    	if (!search) {
    		ret = -ENOMEM;
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_read_xattr_bucket(search, p_blkno);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	xh = bucket_xh(search);
    	high_bucket = le16_to_cpu(xh->xh_num_buckets) - 1;
    	while (low_bucket <= high_bucket) {
    		ocfs2_xattr_bucket_relse(search);
    
    		bucket = (low_bucket + high_bucket) / 2;
    		blkno = p_blkno + bucket * blk_per_bucket;
    		ret = ocfs2_read_xattr_bucket(search, blkno);
    		if (ret) {
    			mlog_errno(ret);
    			goto out;
    		}
    
    		xh = bucket_xh(search);
    		xe = &xh->xh_entries[0];
    		if (name_hash < le32_to_cpu(xe->xe_name_hash)) {
    			high_bucket = bucket - 1;
    			continue;
    		}
    
    		/*
    		 * Check whether the hash of the last entry in our
    		 * bucket is larger than the search one. for an empty
    		 * bucket, the last one is also the first one.
    		 */
    		if (xh->xh_count)
    			xe = &xh->xh_entries[le16_to_cpu(xh->xh_count) - 1];
    
    		last_hash = le32_to_cpu(xe->xe_name_hash);
    
    		/* record lower_blkno which may be the insert place. */
    		lower_blkno = blkno;
    
    		if (name_hash > le32_to_cpu(xe->xe_name_hash)) {
    			low_bucket = bucket + 1;
    			continue;
    		}
    
    		/* the searched xattr should reside in this bucket if exists. */
    		ret = ocfs2_find_xe_in_bucket(inode, search,
    					      name_index, name, name_hash,
    					      &index, &found);
    		if (ret) {
    			mlog_errno(ret);
    			goto out;
    		}
    		break;
    	}
    
    	/*
    	 * Record the bucket we have found.
    	 * When the xattr's hash value is in the gap of 2 buckets, we will
    	 * always set it to the previous bucket.
    	 */
    	if (!lower_blkno)
    		lower_blkno = p_blkno;
    
    	/* This should be in cache - we just read it during the search */
    	ret = ocfs2_read_xattr_bucket(xs->bucket, lower_blkno);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	xs->header = bucket_xh(xs->bucket);
    	xs->base = bucket_block(xs->bucket, 0);
    	xs->end = xs->base + inode->i_sb->s_blocksize;
    
    	if (found) {
    		xs->here = &xs->header->xh_entries[index];
    		trace_ocfs2_xattr_bucket_find(OCFS2_I(inode)->ip_blkno,
    			name, name_index, name_hash,
    			(unsigned long long)bucket_blkno(xs->bucket),
    			index);
    	} else
    		ret = -ENODATA;
    
    out:
    	ocfs2_xattr_bucket_free(search);
    	return ret;
    }
    
    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)
    {
    	int ret;
    	struct ocfs2_xattr_block *xb =
    			(struct ocfs2_xattr_block *)root_bh->b_data;
    	struct ocfs2_xattr_tree_root *xb_root = &xb->xb_attrs.xb_root;
    	struct ocfs2_extent_list *el = &xb_root->xt_list;
    	u64 p_blkno = 0;
    	u32 first_hash, num_clusters = 0;
    	u32 name_hash = ocfs2_xattr_name_hash(inode, name, strlen(name));
    
    	if (le16_to_cpu(el->l_next_free_rec) == 0)
    		return -ENODATA;
    
    	trace_ocfs2_xattr_index_block_find(OCFS2_I(inode)->ip_blkno,
    					name, name_index, name_hash,
    					(unsigned long long)root_bh->b_blocknr,
    					-1);
    
    	ret = ocfs2_xattr_get_rec(inode, name_hash, &p_blkno, &first_hash,
    				  &num_clusters, el);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	BUG_ON(p_blkno == 0 || num_clusters == 0 || first_hash > name_hash);
    
    	trace_ocfs2_xattr_index_block_find_rec(OCFS2_I(inode)->ip_blkno,
    					name, name_index, first_hash,
    					(unsigned long long)p_blkno,
    					num_clusters);
    
    	ret = ocfs2_xattr_bucket_find(inode, name_index, name, name_hash,
    				      p_blkno, first_hash, num_clusters, xs);
    
    out:
    	return ret;
    }
    
    static int ocfs2_iterate_xattr_buckets(struct inode *inode,
    				       u64 blkno,
    				       u32 clusters,
    				       xattr_bucket_func *func,
    				       void *para)
    {
    	int i, ret = 0;
    	u32 bpc = ocfs2_xattr_buckets_per_cluster(OCFS2_SB(inode->i_sb));
    	u32 num_buckets = clusters * bpc;
    	struct ocfs2_xattr_bucket *bucket;
    
    	bucket = ocfs2_xattr_bucket_new(inode);
    	if (!bucket) {
    		mlog_errno(-ENOMEM);
    		return -ENOMEM;
    	}
    
    	trace_ocfs2_iterate_xattr_buckets(
    		(unsigned long long)OCFS2_I(inode)->ip_blkno,
    		(unsigned long long)blkno, clusters);
    
    	for (i = 0; i < num_buckets; i++, blkno += bucket->bu_blocks) {
    		ret = ocfs2_read_xattr_bucket(bucket, blkno);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    		/*
    		 * The real bucket num in this series of blocks is stored
    		 * in the 1st bucket.
    		 */
    		if (i == 0)
    			num_buckets = le16_to_cpu(bucket_xh(bucket)->xh_num_buckets);
    
    		trace_ocfs2_iterate_xattr_bucket((unsigned long long)blkno,
    		     le32_to_cpu(bucket_xh(bucket)->xh_entries[0].xe_name_hash));
    		if (func) {
    			ret = func(inode, bucket, para);
    			if (ret && ret != -ERANGE)
    				mlog_errno(ret);
    			/* Fall through to bucket_relse() */
    		}
    
    		ocfs2_xattr_bucket_relse(bucket);
    		if (ret)
    			break;
    	}
    
    	ocfs2_xattr_bucket_free(bucket);
    	return ret;
    }
    
    struct ocfs2_xattr_tree_list {
    	char *buffer;
    	size_t buffer_size;
    	size_t result;
    };
    
    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)
    {
    	u16 name_offset;
    
    	if (index < 0 || index >= le16_to_cpu(xh->xh_count))
    		return -EINVAL;
    
    	name_offset = le16_to_cpu(xh->xh_entries[index].xe_name_offset);
    
    	*block_off = name_offset >> sb->s_blocksize_bits;
    	*new_offset = name_offset % sb->s_blocksize;
    
    	return 0;
    }
    
    static int ocfs2_list_xattr_bucket(struct inode *inode,
    				   struct ocfs2_xattr_bucket *bucket,
    				   void *para)
    {
    	int ret = 0, type;
    	struct ocfs2_xattr_tree_list *xl = (struct ocfs2_xattr_tree_list *)para;
    	int i, block_off, new_offset;
    	const char *prefix, *name;
    
    	for (i = 0 ; i < le16_to_cpu(bucket_xh(bucket)->xh_count); i++) {
    		struct ocfs2_xattr_entry *entry = &bucket_xh(bucket)->xh_entries[i];
    		type = ocfs2_xattr_get_type(entry);
    		prefix = ocfs2_xattr_prefix(type);
    
    		if (prefix) {
    			ret = ocfs2_xattr_bucket_get_name_value(inode->i_sb,
    								bucket_xh(bucket),
    								i,
    								&block_off,
    								&new_offset);
    			if (ret)
    				break;
    
    			name = (const char *)bucket_block(bucket, block_off) +
    				new_offset;
    			ret = ocfs2_xattr_list_entry(xl->buffer,
    						     xl->buffer_size,
    						     &xl->result,
    						     prefix, name,
    						     entry->xe_name_len);
    			if (ret)
    				break;
    		}
    	}
    
    	return ret;
    }
    
    static int ocfs2_iterate_xattr_index_block(struct inode *inode,
    					   struct buffer_head *blk_bh,
    					   xattr_tree_rec_func *rec_func,
    					   void *para)
    {
    	struct ocfs2_xattr_block *xb =
    			(struct ocfs2_xattr_block *)blk_bh->b_data;
    	struct ocfs2_extent_list *el = &xb->xb_attrs.xb_root.xt_list;
    	int ret = 0;
    	u32 name_hash = UINT_MAX, e_cpos = 0, num_clusters = 0;
    	u64 p_blkno = 0;
    
    	if (!el->l_next_free_rec || !rec_func)
    		return 0;
    
    	while (name_hash > 0) {
    		ret = ocfs2_xattr_get_rec(inode, name_hash, &p_blkno,
    					  &e_cpos, &num_clusters, el);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    		ret = rec_func(inode, blk_bh, p_blkno, e_cpos,
    			       num_clusters, para);
    		if (ret) {
    			if (ret != -ERANGE)
    				mlog_errno(ret);
    			break;
    		}
    
    		if (e_cpos == 0)
    			break;
    
    		name_hash = e_cpos - 1;
    	}
    
    	return ret;
    
    }
    
    static int ocfs2_list_xattr_tree_rec(struct inode *inode,
    				     struct buffer_head *root_bh,
    				     u64 blkno, u32 cpos, u32 len, void *para)
    {
    	return ocfs2_iterate_xattr_buckets(inode, blkno, len,
    					   ocfs2_list_xattr_bucket, para);
    }
    
    static int ocfs2_xattr_tree_list_index_block(struct inode *inode,
    					     struct buffer_head *blk_bh,
    					     char *buffer,
    					     size_t buffer_size)
    {
    	int ret;
    	struct ocfs2_xattr_tree_list xl = {
    		.buffer = buffer,
    		.buffer_size = buffer_size,
    		.result = 0,
    	};
    
    	ret = ocfs2_iterate_xattr_index_block(inode, blk_bh,
    					      ocfs2_list_xattr_tree_rec, &xl);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = xl.result;
    out:
    	return ret;
    }
    
    static int cmp_xe(const void *a, const void *b)
    {
    	const struct ocfs2_xattr_entry *l = a, *r = b;
    	u32 l_hash = le32_to_cpu(l->xe_name_hash);
    	u32 r_hash = le32_to_cpu(r->xe_name_hash);
    
    	if (l_hash > r_hash)
    		return 1;
    	if (l_hash < r_hash)
    		return -1;
    	return 0;
    }
    
    static void swap_xe(void *a, void *b, int size)
    {
    	struct ocfs2_xattr_entry *l = a, *r = b, tmp;
    
    	tmp = *l;
    	memcpy(l, r, sizeof(struct ocfs2_xattr_entry));
    	memcpy(r, &tmp, sizeof(struct ocfs2_xattr_entry));
    }
    
    /*
     * When the ocfs2_xattr_block is filled up, new bucket will be created
     * and all the xattr entries will be moved to the new bucket.
     * The header goes at the start of the bucket, and the names+values are
     * filled from the end.  This is why *target starts as the last buffer.
     * Note: we need to sort the entries since they are not saved in order
     * in the ocfs2_xattr_block.
     */
    static void ocfs2_cp_xattr_block_to_bucket(struct inode *inode,
    					   struct buffer_head *xb_bh,
    					   struct ocfs2_xattr_bucket *bucket)
    {
    	int i, blocksize = inode->i_sb->s_blocksize;
    	int blks = ocfs2_blocks_per_xattr_bucket(inode->i_sb);
    	u16 offset, size, off_change;
    	struct ocfs2_xattr_entry *xe;
    	struct ocfs2_xattr_block *xb =
    				(struct ocfs2_xattr_block *)xb_bh->b_data;
    	struct ocfs2_xattr_header *xb_xh = &xb->xb_attrs.xb_header;
    	struct ocfs2_xattr_header *xh = bucket_xh(bucket);
    	u16 count = le16_to_cpu(xb_xh->xh_count);
    	char *src = xb_bh->b_data;
    	char *target = bucket_block(bucket, blks - 1);
    
    	trace_ocfs2_cp_xattr_block_to_bucket_begin(
    				(unsigned long long)xb_bh->b_blocknr,
    				(unsigned long long)bucket_blkno(bucket));
    
    	for (i = 0; i < blks; i++)
    		memset(bucket_block(bucket, i), 0, blocksize);
    
    	/*
    	 * Since the xe_name_offset is based on ocfs2_xattr_header,
    	 * there is a offset change corresponding to the change of
    	 * ocfs2_xattr_header's position.
    	 */
    	off_change = offsetof(struct ocfs2_xattr_block, xb_attrs.xb_header);
    	xe = &xb_xh->xh_entries[count - 1];
    	offset = le16_to_cpu(xe->xe_name_offset) + off_change;
    	size = blocksize - offset;
    
    	/* copy all the names and values. */
    	memcpy(target + offset, src + offset, size);
    
    	/* Init new header now. */
    	xh->xh_count = xb_xh->xh_count;
    	xh->xh_num_buckets = cpu_to_le16(1);
    	xh->xh_name_value_len = cpu_to_le16(size);
    	xh->xh_free_start = cpu_to_le16(OCFS2_XATTR_BUCKET_SIZE - size);
    
    	/* copy all the entries. */
    	target = bucket_block(bucket, 0);
    	offset = offsetof(struct ocfs2_xattr_header, xh_entries);
    	size = count * sizeof(struct ocfs2_xattr_entry);
    	memcpy(target + offset, (char *)xb_xh + offset, size);
    
    	/* Change the xe offset for all the xe because of the move. */
    	off_change = OCFS2_XATTR_BUCKET_SIZE - blocksize +
    		 offsetof(struct ocfs2_xattr_block, xb_attrs.xb_header);
    	for (i = 0; i < count; i++)
    		le16_add_cpu(&xh->xh_entries[i].xe_name_offset, off_change);
    
    	trace_ocfs2_cp_xattr_block_to_bucket_end(offset, size, off_change);
    
    	sort(target + offset, count, sizeof(struct ocfs2_xattr_entry),
    	     cmp_xe, swap_xe);
    }
    
    /*
     * After we move xattr from block to index btree, we have to
     * update ocfs2_xattr_search to the new xe and base.
     *
     * When the entry is in xattr block, xattr_bh indicates the storage place.
     * While if the entry is in index b-tree, "bucket" indicates the
     * real place of the xattr.
     */
    static void ocfs2_xattr_update_xattr_search(struct inode *inode,
    					    struct ocfs2_xattr_search *xs,
    					    struct buffer_head *old_bh)
    {
    	char *buf = old_bh->b_data;
    	struct ocfs2_xattr_block *old_xb = (struct ocfs2_xattr_block *)buf;
    	struct ocfs2_xattr_header *old_xh = &old_xb->xb_attrs.xb_header;
    	int i;
    
    	xs->header = bucket_xh(xs->bucket);
    	xs->base = bucket_block(xs->bucket, 0);
    	xs->end = xs->base + inode->i_sb->s_blocksize;
    
    	if (xs->not_found)
    		return;
    
    	i = xs->here - old_xh->xh_entries;
    	xs->here = &xs->header->xh_entries[i];
    }
    
    static int ocfs2_xattr_create_index_block(struct inode *inode,
    					  struct ocfs2_xattr_search *xs,
    					  struct ocfs2_xattr_set_ctxt *ctxt)
    {
    	int ret;
    	u32 bit_off, len;
    	u64 blkno;
    	handle_t *handle = ctxt->handle;
    	struct ocfs2_inode_info *oi = OCFS2_I(inode);
    	struct buffer_head *xb_bh = xs->xattr_bh;
    	struct ocfs2_xattr_block *xb =
    			(struct ocfs2_xattr_block *)xb_bh->b_data;
    	struct ocfs2_xattr_tree_root *xr;
    	u16 xb_flags = le16_to_cpu(xb->xb_flags);
    
    	trace_ocfs2_xattr_create_index_block_begin(
    				(unsigned long long)xb_bh->b_blocknr);
    
    	BUG_ON(xb_flags & OCFS2_XATTR_INDEXED);
    	BUG_ON(!xs->bucket);
    
    	/*
    	 * XXX:
    	 * We can use this lock for now, and maybe move to a dedicated mutex
    	 * if performance becomes a problem later.
    	 */
    	down_write(&oi->ip_alloc_sem);
    
    	ret = ocfs2_journal_access_xb(handle, INODE_CACHE(inode), xb_bh,
    				      OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = __ocfs2_claim_clusters(handle, ctxt->data_ac,
    				     1, 1, &bit_off, &len);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	/*
    	 * The bucket may spread in many blocks, and
    	 * we will only touch the 1st block and the last block
    	 * in the whole bucket(one for entry and one for data).
    	 */
    	blkno = ocfs2_clusters_to_blocks(inode->i_sb, bit_off);
    
    	trace_ocfs2_xattr_create_index_block((unsigned long long)blkno);
    
    	ret = ocfs2_init_xattr_bucket(xs->bucket, blkno, 1);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_xattr_bucket_journal_access(handle, xs->bucket,
    						OCFS2_JOURNAL_ACCESS_CREATE);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ocfs2_cp_xattr_block_to_bucket(inode, xb_bh, xs->bucket);
    	ocfs2_xattr_bucket_journal_dirty(handle, xs->bucket);
    
    	ocfs2_xattr_update_xattr_search(inode, xs, xb_bh);
    
    	/* Change from ocfs2_xattr_header to ocfs2_xattr_tree_root */
    	memset(&xb->xb_attrs, 0, inode->i_sb->s_blocksize -
    	       offsetof(struct ocfs2_xattr_block, xb_attrs));
    
    	xr = &xb->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);
    
    	xr->xt_list.l_recs[0].e_cpos = 0;
    	xr->xt_list.l_recs[0].e_blkno = cpu_to_le64(blkno);
    	xr->xt_list.l_recs[0].e_leaf_clusters = cpu_to_le16(1);
    
    	xb->xb_flags = cpu_to_le16(xb_flags | OCFS2_XATTR_INDEXED);
    
    	ocfs2_journal_dirty(handle, xb_bh);
    
    out:
    	up_write(&oi->ip_alloc_sem);
    
    	return ret;
    }
    
    static int cmp_xe_offset(const void *a, const void *b)
    {
    	const struct ocfs2_xattr_entry *l = a, *r = b;
    	u32 l_name_offset = le16_to_cpu(l->xe_name_offset);
    	u32 r_name_offset = le16_to_cpu(r->xe_name_offset);
    
    	if (l_name_offset < r_name_offset)
    		return 1;
    	if (l_name_offset > r_name_offset)
    		return -1;
    	return 0;
    }
    
    /*
     * defrag a xattr bucket if we find that the bucket has some
     * holes beteen name/value pairs.
     * We will move all the name/value pairs to the end of the bucket
     * so that we can spare some space for insertion.
     */
    static int ocfs2_defrag_xattr_bucket(struct inode *inode,
    				     handle_t *handle,
    				     struct ocfs2_xattr_bucket *bucket)
    {
    	int ret, i;
    	size_t end, offset, len;
    	struct ocfs2_xattr_header *xh;
    	char *entries, *buf, *bucket_buf = NULL;
    	u64 blkno = bucket_blkno(bucket);
    	u16 xh_free_start;
    	size_t blocksize = inode->i_sb->s_blocksize;
    	struct ocfs2_xattr_entry *xe;
    
    	/*
    	 * In order to make the operation more efficient and generic,
    	 * we copy all the blocks into a contiguous memory and do the
    	 * defragment there, so if anything is error, we will not touch
    	 * the real block.
    	 */
    	bucket_buf = kmalloc(OCFS2_XATTR_BUCKET_SIZE, GFP_NOFS);
    	if (!bucket_buf) {
    		ret = -EIO;
    		goto out;
    	}
    
    	buf = bucket_buf;
    	for (i = 0; i < bucket->bu_blocks; i++, buf += blocksize)
    		memcpy(buf, bucket_block(bucket, i), blocksize);
    
    	ret = ocfs2_xattr_bucket_journal_access(handle, bucket,
    						OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret < 0) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	xh = (struct ocfs2_xattr_header *)bucket_buf;
    	entries = (char *)xh->xh_entries;
    	xh_free_start = le16_to_cpu(xh->xh_free_start);
    
    	trace_ocfs2_defrag_xattr_bucket(
    	     (unsigned long long)blkno, le16_to_cpu(xh->xh_count),
    	     xh_free_start, le16_to_cpu(xh->xh_name_value_len));
    
    	/*
    	 * sort all the entries by their offset.
    	 * the largest will be the first, so that we can
    	 * move them to the end one by one.
    	 */
    	sort(entries, le16_to_cpu(xh->xh_count),
    	     sizeof(struct ocfs2_xattr_entry),
    	     cmp_xe_offset, swap_xe);
    
    	/* Move all name/values to the end of the bucket. */
    	xe = xh->xh_entries;
    	end = OCFS2_XATTR_BUCKET_SIZE;
    	for (i = 0; i < le16_to_cpu(xh->xh_count); i++, xe++) {
    		offset = le16_to_cpu(xe->xe_name_offset);
    		len = namevalue_size_xe(xe);
    
    		/*
    		 * We must make sure that the name/value pair
    		 * exist in the same block. So adjust end to
    		 * the previous block end if needed.
    		 */
    		if (((end - len) / blocksize !=
    			(end - 1) / blocksize))
    			end = end - end % blocksize;
    
    		if (end > offset + len) {
    			memmove(bucket_buf + end - len,
    				bucket_buf + offset, len);
    			xe->xe_name_offset = cpu_to_le16(end - len);
    		}
    
    		mlog_bug_on_msg(end < offset + len, "Defrag check failed for "
    				"bucket %llu\n", (unsigned long long)blkno);
    
    		end -= len;
    	}
    
    	mlog_bug_on_msg(xh_free_start > end, "Defrag check failed for "
    			"bucket %llu\n", (unsigned long long)blkno);
    
    	if (xh_free_start == end)
    		goto out;
    
    	memset(bucket_buf + xh_free_start, 0, end - xh_free_start);
    	xh->xh_free_start = cpu_to_le16(end);
    
    	/* sort the entries by their name_hash. */
    	sort(entries, le16_to_cpu(xh->xh_count),
    	     sizeof(struct ocfs2_xattr_entry),
    	     cmp_xe, swap_xe);
    
    	buf = bucket_buf;
    	for (i = 0; i < bucket->bu_blocks; i++, buf += blocksize)
    		memcpy(bucket_block(bucket, i), buf, blocksize);
    	ocfs2_xattr_bucket_journal_dirty(handle, bucket);
    
    out:
    	kfree(bucket_buf);
    	return ret;
    }
    
    /*
     * prev_blkno points to the start of an existing extent.  new_blkno
     * points to a newly allocated extent.  Because we know each of our
     * clusters contains more than bucket, we can easily split one cluster
     * at a bucket boundary.  So we take the last cluster of the existing
     * extent and split it down the middle.  We move the last half of the
     * buckets in the last cluster of the existing extent over to the new
     * extent.
     *
     * first_bh is the buffer at prev_blkno so we can update the existing
     * extent's bucket count.  header_bh is the bucket were we were hoping
     * to insert our xattr.  If the bucket move places the target in the new
     * extent, we'll update first_bh and header_bh after modifying the old
     * extent.
     *
     * first_hash will be set as the 1st xe's name_hash in the new extent.
     */
    static int ocfs2_mv_xattr_bucket_cross_cluster(struct inode *inode,
    					       handle_t *handle,
    					       struct ocfs2_xattr_bucket *first,
    					       struct ocfs2_xattr_bucket *target,
    					       u64 new_blkno,
    					       u32 num_clusters,
    					       u32 *first_hash)
    {
    	int ret;
    	struct super_block *sb = inode->i_sb;
    	int blks_per_bucket = ocfs2_blocks_per_xattr_bucket(sb);
    	int num_buckets = ocfs2_xattr_buckets_per_cluster(OCFS2_SB(sb));
    	int to_move = num_buckets / 2;
    	u64 src_blkno;
    	u64 last_cluster_blkno = bucket_blkno(first) +
    		((num_clusters - 1) * ocfs2_clusters_to_blocks(sb, 1));
    
    	BUG_ON(le16_to_cpu(bucket_xh(first)->xh_num_buckets) < num_buckets);
    	BUG_ON(OCFS2_XATTR_BUCKET_SIZE == OCFS2_SB(sb)->s_clustersize);
    
    	trace_ocfs2_mv_xattr_bucket_cross_cluster(
    				(unsigned long long)last_cluster_blkno,
    				(unsigned long long)new_blkno);
    
    	ret = ocfs2_mv_xattr_buckets(inode, handle, bucket_blkno(first),
    				     last_cluster_blkno, new_blkno,
    				     to_move, first_hash);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	/* This is the first bucket that got moved */
    	src_blkno = last_cluster_blkno + (to_move * blks_per_bucket);
    
    	/*
    	 * If the target bucket was part of the moved buckets, we need to
    	 * update first and target.
    	 */
    	if (bucket_blkno(target) >= src_blkno) {
    		/* Find the block for the new target bucket */
    		src_blkno = new_blkno +
    			(bucket_blkno(target) - src_blkno);
    
    		ocfs2_xattr_bucket_relse(first);
    		ocfs2_xattr_bucket_relse(target);
    
    		/*
    		 * These shouldn't fail - the buffers are in the
    		 * journal from ocfs2_cp_xattr_bucket().
    		 */
    		ret = ocfs2_read_xattr_bucket(first, new_blkno);
    		if (ret) {
    			mlog_errno(ret);
    			goto out;
    		}
    		ret = ocfs2_read_xattr_bucket(target, src_blkno);
    		if (ret)
    			mlog_errno(ret);
    
    	}
    
    out:
    	return ret;
    }
    
    /*
     * Find the suitable pos when we divide a bucket into 2.
     * We have to make sure the xattrs with the same hash value exist
     * in the same bucket.
     *
     * If this ocfs2_xattr_header covers more than one hash value, find a
     * place where the hash value changes.  Try to find the most even split.
     * The most common case is that all entries have different hash values,
     * and the first check we make will find a place to split.
     */
    static int ocfs2_xattr_find_divide_pos(struct ocfs2_xattr_header *xh)
    {
    	struct ocfs2_xattr_entry *entries = xh->xh_entries;
    	int count = le16_to_cpu(xh->xh_count);
    	int delta, middle = count / 2;
    
    	/*
    	 * We start at the middle.  Each step gets farther away in both
    	 * directions.  We therefore hit the change in hash value
    	 * nearest to the middle.  Note that this loop does not execute for
    	 * count < 2.
    	 */
    	for (delta = 0; delta < middle; delta++) {
    		/* Let's check delta earlier than middle */
    		if (cmp_xe(&entries[middle - delta - 1],
    			   &entries[middle - delta]))
    			return middle - delta;
    
    		/* For even counts, don't walk off the end */
    		if ((middle + delta + 1) == count)
    			continue;
    
    		/* Now try delta past middle */
    		if (cmp_xe(&entries[middle + delta],
    			   &entries[middle + delta + 1]))
    			return middle + delta + 1;
    	}
    
    	/* Every entry had the same hash */
    	return count;
    }
    
    /*
     * Move some xattrs in old bucket(blk) to new bucket(new_blk).
     * first_hash will record the 1st hash of the new bucket.
     *
     * Normally half of the xattrs will be moved.  But we have to make
     * sure that the xattrs with the same hash value are stored in the
     * same bucket. If all the xattrs in this bucket have the same hash
     * value, the new bucket will be initialized as an empty one and the
     * first_hash will be initialized as (hash_value+1).
     */
    static int ocfs2_divide_xattr_bucket(struct inode *inode,
    				    handle_t *handle,
    				    u64 blk,
    				    u64 new_blk,
    				    u32 *first_hash,
    				    int new_bucket_head)
    {
    	int ret, i;
    	int count, start, len, name_value_len = 0, name_offset = 0;
    	struct ocfs2_xattr_bucket *s_bucket = NULL, *t_bucket = NULL;
    	struct ocfs2_xattr_header *xh;
    	struct ocfs2_xattr_entry *xe;
    	int blocksize = inode->i_sb->s_blocksize;
    
    	trace_ocfs2_divide_xattr_bucket_begin((unsigned long long)blk,
    					      (unsigned long long)new_blk);
    
    	s_bucket = ocfs2_xattr_bucket_new(inode);
    	t_bucket = ocfs2_xattr_bucket_new(inode);
    	if (!s_bucket || !t_bucket) {
    		ret = -ENOMEM;
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_read_xattr_bucket(s_bucket, blk);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_xattr_bucket_journal_access(handle, s_bucket,
    						OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	/*
    	 * Even if !new_bucket_head, we're overwriting t_bucket.  Thus,
    	 * there's no need to read it.
    	 */
    	ret = ocfs2_init_xattr_bucket(t_bucket, new_blk, new_bucket_head);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	/*
    	 * Hey, if we're overwriting t_bucket, what difference does
    	 * ACCESS_CREATE vs ACCESS_WRITE make?  See the comment in the
    	 * same part of ocfs2_cp_xattr_bucket().
    	 */
    	ret = ocfs2_xattr_bucket_journal_access(handle, t_bucket,
    						new_bucket_head ?
    						OCFS2_JOURNAL_ACCESS_CREATE :
    						OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	xh = bucket_xh(s_bucket);
    	count = le16_to_cpu(xh->xh_count);
    	start = ocfs2_xattr_find_divide_pos(xh);
    
    	if (start == count) {
    		xe = &xh->xh_entries[start-1];
    
    		/*
    		 * initialized a new empty bucket here.
    		 * The hash value is set as one larger than
    		 * that of the last entry in the previous bucket.
    		 */
    		for (i = 0; i < t_bucket->bu_blocks; i++)
    			memset(bucket_block(t_bucket, i), 0, blocksize);
    
    		xh = bucket_xh(t_bucket);
    		xh->xh_free_start = cpu_to_le16(blocksize);
    		xh->xh_entries[0].xe_name_hash = xe->xe_name_hash;
    		le32_add_cpu(&xh->xh_entries[0].xe_name_hash, 1);
    
    		goto set_num_buckets;
    	}
    
    	/* copy the whole bucket to the new first. */
    	ocfs2_xattr_bucket_copy_data(t_bucket, s_bucket);
    
    	/* update the new bucket. */
    	xh = bucket_xh(t_bucket);
    
    	/*
    	 * Calculate the total name/value len and xh_free_start for
    	 * the old bucket first.
    	 */
    	name_offset = OCFS2_XATTR_BUCKET_SIZE;
    	name_value_len = 0;
    	for (i = 0; i < start; i++) {
    		xe = &xh->xh_entries[i];
    		name_value_len += namevalue_size_xe(xe);
    		if (le16_to_cpu(xe->xe_name_offset) < name_offset)
    			name_offset = le16_to_cpu(xe->xe_name_offset);
    	}
    
    	/*
    	 * Now begin the modification to the new bucket.
    	 *
    	 * In the new bucket, We just move the xattr entry to the beginning
    	 * and don't touch the name/value. So there will be some holes in the
    	 * bucket, and they will be removed when ocfs2_defrag_xattr_bucket is
    	 * called.
    	 */
    	xe = &xh->xh_entries[start];
    	len = sizeof(struct ocfs2_xattr_entry) * (count - start);
    	trace_ocfs2_divide_xattr_bucket_move(len,
    			(int)((char *)xe - (char *)xh),
    			(int)((char *)xh->xh_entries - (char *)xh));
    	memmove((char *)xh->xh_entries, (char *)xe, len);
    	xe = &xh->xh_entries[count - start];
    	len = sizeof(struct ocfs2_xattr_entry) * start;
    	memset((char *)xe, 0, len);
    
    	le16_add_cpu(&xh->xh_count, -start);
    	le16_add_cpu(&xh->xh_name_value_len, -name_value_len);
    
    	/* Calculate xh_free_start for the new bucket. */
    	xh->xh_free_start = cpu_to_le16(OCFS2_XATTR_BUCKET_SIZE);
    	for (i = 0; i < le16_to_cpu(xh->xh_count); i++) {
    		xe = &xh->xh_entries[i];
    		if (le16_to_cpu(xe->xe_name_offset) <
    		    le16_to_cpu(xh->xh_free_start))
    			xh->xh_free_start = xe->xe_name_offset;
    	}
    
    set_num_buckets:
    	/* set xh->xh_num_buckets for the new xh. */
    	if (new_bucket_head)
    		xh->xh_num_buckets = cpu_to_le16(1);
    	else
    		xh->xh_num_buckets = 0;
    
    	ocfs2_xattr_bucket_journal_dirty(handle, t_bucket);
    
    	/* store the first_hash of the new bucket. */
    	if (first_hash)
    		*first_hash = le32_to_cpu(xh->xh_entries[0].xe_name_hash);
    
    	/*
    	 * Now only update the 1st block of the old bucket.  If we
    	 * just added a new empty bucket, there is no need to modify
    	 * it.
    	 */
    	if (start == count)
    		goto out;
    
    	xh = bucket_xh(s_bucket);
    	memset(&xh->xh_entries[start], 0,
    	       sizeof(struct ocfs2_xattr_entry) * (count - start));
    	xh->xh_count = cpu_to_le16(start);
    	xh->xh_free_start = cpu_to_le16(name_offset);
    	xh->xh_name_value_len = cpu_to_le16(name_value_len);
    
    	ocfs2_xattr_bucket_journal_dirty(handle, s_bucket);
    
    out:
    	ocfs2_xattr_bucket_free(s_bucket);
    	ocfs2_xattr_bucket_free(t_bucket);
    
    	return ret;
    }
    
    /*
     * Copy xattr from one bucket to another bucket.
     *
     * The caller must make sure that the journal transaction
     * has enough space for journaling.
     */
    static int ocfs2_cp_xattr_bucket(struct inode *inode,
    				 handle_t *handle,
    				 u64 s_blkno,
    				 u64 t_blkno,
    				 int t_is_new)
    {
    	int ret;
    	struct ocfs2_xattr_bucket *s_bucket = NULL, *t_bucket = NULL;
    
    	BUG_ON(s_blkno == t_blkno);
    
    	trace_ocfs2_cp_xattr_bucket((unsigned long long)s_blkno,
    				    (unsigned long long)t_blkno,
    				    t_is_new);
    
    	s_bucket = ocfs2_xattr_bucket_new(inode);
    	t_bucket = ocfs2_xattr_bucket_new(inode);
    	if (!s_bucket || !t_bucket) {
    		ret = -ENOMEM;
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_read_xattr_bucket(s_bucket, s_blkno);
    	if (ret)
    		goto out;
    
    	/*
    	 * Even if !t_is_new, we're overwriting t_bucket.  Thus,
    	 * there's no need to read it.
    	 */
    	ret = ocfs2_init_xattr_bucket(t_bucket, t_blkno, t_is_new);
    	if (ret)
    		goto out;
    
    	/*
    	 * Hey, if we're overwriting t_bucket, what difference does
    	 * ACCESS_CREATE vs ACCESS_WRITE make?  Well, if we allocated a new
    	 * cluster to fill, we came here from
    	 * ocfs2_mv_xattr_buckets(), and it is really new -
    	 * ACCESS_CREATE is required.  But we also might have moved data
    	 * out of t_bucket before extending back into it.
    	 * ocfs2_add_new_xattr_bucket() can do this - its call to
    	 * ocfs2_add_new_xattr_cluster() may have created a new extent
    	 * and copied out the end of the old extent.  Then it re-extends
    	 * the old extent back to create space for new xattrs.  That's
    	 * how we get here, and the bucket isn't really new.
    	 */
    	ret = ocfs2_xattr_bucket_journal_access(handle, t_bucket,
    						t_is_new ?
    						OCFS2_JOURNAL_ACCESS_CREATE :
    						OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret)
    		goto out;
    
    	ocfs2_xattr_bucket_copy_data(t_bucket, s_bucket);
    	ocfs2_xattr_bucket_journal_dirty(handle, t_bucket);
    
    out:
    	ocfs2_xattr_bucket_free(t_bucket);
    	ocfs2_xattr_bucket_free(s_bucket);
    
    	return ret;
    }
    
    /*
     * src_blk points to the start of an existing extent.  last_blk points to
     * last cluster in that extent.  to_blk points to a newly allocated
     * extent.  We copy the buckets from the cluster at last_blk to the new
     * extent.  If start_bucket is non-zero, we skip that many buckets before
     * we start copying.  The new extent's xh_num_buckets gets set to the
     * number of buckets we copied.  The old extent's xh_num_buckets shrinks
     * by the same amount.
     */
    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)
    {
    	int i, ret, credits;
    	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
    	int blks_per_bucket = ocfs2_blocks_per_xattr_bucket(inode->i_sb);
    	int num_buckets = ocfs2_xattr_buckets_per_cluster(osb);
    	struct ocfs2_xattr_bucket *old_first, *new_first;
    
    	trace_ocfs2_mv_xattr_buckets((unsigned long long)last_blk,
    				     (unsigned long long)to_blk);
    
    	BUG_ON(start_bucket >= num_buckets);
    	if (start_bucket) {
    		num_buckets -= start_bucket;
    		last_blk += (start_bucket * blks_per_bucket);
    	}
    
    	/* The first bucket of the original extent */
    	old_first = ocfs2_xattr_bucket_new(inode);
    	/* The first bucket of the new extent */
    	new_first = ocfs2_xattr_bucket_new(inode);
    	if (!old_first || !new_first) {
    		ret = -ENOMEM;
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_read_xattr_bucket(old_first, src_blk);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	/*
    	 * We need to update the first bucket of the old extent and all
    	 * the buckets going to the new extent.
    	 */
    	credits = ((num_buckets + 1) * blks_per_bucket);
    	ret = ocfs2_extend_trans(handle, credits);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_xattr_bucket_journal_access(handle, old_first,
    						OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	for (i = 0; i < num_buckets; i++) {
    		ret = ocfs2_cp_xattr_bucket(inode, handle,
    					    last_blk + (i * blks_per_bucket),
    					    to_blk + (i * blks_per_bucket),
    					    1);
    		if (ret) {
    			mlog_errno(ret);
    			goto out;
    		}
    	}
    
    	/*
    	 * Get the new bucket ready before we dirty anything
    	 * (This actually shouldn't fail, because we already dirtied
    	 * it once in ocfs2_cp_xattr_bucket()).
    	 */
    	ret = ocfs2_read_xattr_bucket(new_first, to_blk);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    	ret = ocfs2_xattr_bucket_journal_access(handle, new_first,
    						OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	/* Now update the headers */
    	le16_add_cpu(&bucket_xh(old_first)->xh_num_buckets, -num_buckets);
    	ocfs2_xattr_bucket_journal_dirty(handle, old_first);
    
    	bucket_xh(new_first)->xh_num_buckets = cpu_to_le16(num_buckets);
    	ocfs2_xattr_bucket_journal_dirty(handle, new_first);
    
    	if (first_hash)
    		*first_hash = le32_to_cpu(bucket_xh(new_first)->xh_entries[0].xe_name_hash);
    
    out:
    	ocfs2_xattr_bucket_free(new_first);
    	ocfs2_xattr_bucket_free(old_first);
    	return ret;
    }
    
    /*
     * Move some xattrs in this cluster to the new cluster.
     * This function should only be called when bucket size == cluster size.
     * Otherwise ocfs2_mv_xattr_bucket_cross_cluster should be used instead.
     */
    static int ocfs2_divide_xattr_cluster(struct inode *inode,
    				      handle_t *handle,
    				      u64 prev_blk,
    				      u64 new_blk,
    				      u32 *first_hash)
    {
    	u16 blk_per_bucket = ocfs2_blocks_per_xattr_bucket(inode->i_sb);
    	int ret, credits = 2 * blk_per_bucket;
    
    	BUG_ON(OCFS2_XATTR_BUCKET_SIZE < OCFS2_SB(inode->i_sb)->s_clustersize);
    
    	ret = ocfs2_extend_trans(handle, credits);
    	if (ret) {
    		mlog_errno(ret);
    		return ret;
    	}
    
    	/* Move half of the xattr in start_blk to the next bucket. */
    	return  ocfs2_divide_xattr_bucket(inode, handle, prev_blk,
    					  new_blk, first_hash, 1);
    }
    
    /*
     * Move some xattrs from the old cluster to the new one since they are not
     * contiguous in ocfs2 xattr tree.
     *
     * new_blk starts a new separate cluster, and we will move some xattrs from
     * prev_blk to it. v_start will be set as the first name hash value in this
     * new cluster so that it can be used as e_cpos during tree insertion and
     * don't collide with our original b-tree operations. first_bh and header_bh
     * will also be updated since they will be used in ocfs2_extend_xattr_bucket
     * to extend the insert bucket.
     *
     * The problem is how much xattr should we move to the new one and when should
     * we update first_bh and header_bh?
     * 1. If cluster size > bucket size, that means the previous cluster has more
     *    than 1 bucket, so just move half nums of bucket into the new cluster and
     *    update the first_bh and header_bh if the insert bucket has been moved
     *    to the new cluster.
     * 2. If cluster_size == bucket_size:
     *    a) If the previous extent rec has more than one cluster and the insert
     *       place isn't in the last cluster, copy the entire last cluster to the
     *       new one. This time, we don't need to upate the first_bh and header_bh
     *       since they will not be moved into the new cluster.
     *    b) Otherwise, move the bottom half of the xattrs in the last cluster into
     *       the new one. And we set the extend flag to zero if the insert place is
     *       moved into the new allocated cluster since no extend is needed.
     */
    static int ocfs2_adjust_xattr_cross_cluster(struct inode *inode,
    					    handle_t *handle,
    					    struct ocfs2_xattr_bucket *first,
    					    struct ocfs2_xattr_bucket *target,
    					    u64 new_blk,
    					    u32 prev_clusters,
    					    u32 *v_start,
    					    int *extend)
    {
    	int ret;
    
    	trace_ocfs2_adjust_xattr_cross_cluster(
    			(unsigned long long)bucket_blkno(first),
    			(unsigned long long)new_blk, prev_clusters);
    
    	if (ocfs2_xattr_buckets_per_cluster(OCFS2_SB(inode->i_sb)) > 1) {
    		ret = ocfs2_mv_xattr_bucket_cross_cluster(inode,
    							  handle,
    							  first, target,
    							  new_blk,
    							  prev_clusters,
    							  v_start);
    		if (ret)
    			mlog_errno(ret);
    	} else {
    		/* The start of the last cluster in the first extent */
    		u64 last_blk = bucket_blkno(first) +
    			((prev_clusters - 1) *
    			 ocfs2_clusters_to_blocks(inode->i_sb, 1));
    
    		if (prev_clusters > 1 && bucket_blkno(target) != last_blk) {
    			ret = ocfs2_mv_xattr_buckets(inode, handle,
    						     bucket_blkno(first),
    						     last_blk, new_blk, 0,
    						     v_start);
    			if (ret)
    				mlog_errno(ret);
    		} else {
    			ret = ocfs2_divide_xattr_cluster(inode, handle,
    							 last_blk, new_blk,
    							 v_start);
    			if (ret)
    				mlog_errno(ret);
    
    			if ((bucket_blkno(target) == last_blk) && extend)
    				*extend = 0;
    		}
    	}
    
    	return ret;
    }
    
    /*
     * Add a new cluster for xattr storage.
     *
     * If the new cluster is contiguous with the previous one, it will be
     * appended to the same extent record, and num_clusters will be updated.
     * If not, we will insert a new extent for it and move some xattrs in
     * the last cluster into the new allocated one.
     * We also need to limit the maximum size of a btree leaf, otherwise we'll
     * lose the benefits of hashing because we'll have to search large leaves.
     * So now the maximum size is OCFS2_MAX_XATTR_TREE_LEAF_SIZE(or clustersize,
     * if it's bigger).
     *
     * first_bh is the first block of the previous extent rec and header_bh
     * indicates the bucket we will insert the new xattrs. They will be updated
     * when the header_bh is moved into the new cluster.
     */
    static int ocfs2_add_new_xattr_cluster(struct inode *inode,
    				       struct buffer_head *root_bh,
    				       struct ocfs2_xattr_bucket *first,
    				       struct ocfs2_xattr_bucket *target,
    				       u32 *num_clusters,
    				       u32 prev_cpos,
    				       int *extend,
    				       struct ocfs2_xattr_set_ctxt *ctxt)
    {
    	int ret;
    	u16 bpc = ocfs2_clusters_to_blocks(inode->i_sb, 1);
    	u32 prev_clusters = *num_clusters;
    	u32 clusters_to_add = 1, bit_off, num_bits, v_start = 0;
    	u64 block;
    	handle_t *handle = ctxt->handle;
    	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
    	struct ocfs2_extent_tree et;
    
    	trace_ocfs2_add_new_xattr_cluster_begin(
    		(unsigned long long)OCFS2_I(inode)->ip_blkno,
    		(unsigned long long)bucket_blkno(first),
    		prev_cpos, prev_clusters);
    
    	ocfs2_init_xattr_tree_extent_tree(&et, INODE_CACHE(inode), root_bh);
    
    	ret = ocfs2_journal_access_xb(handle, INODE_CACHE(inode), root_bh,
    				      OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret < 0) {
    		mlog_errno(ret);
    		goto leave;
    	}
    
    	ret = __ocfs2_claim_clusters(handle, ctxt->data_ac, 1,
    				     clusters_to_add, &bit_off, &num_bits);
    	if (ret < 0) {
    		if (ret != -ENOSPC)
    			mlog_errno(ret);
    		goto leave;
    	}
    
    	BUG_ON(num_bits > clusters_to_add);
    
    	block = ocfs2_clusters_to_blocks(osb->sb, bit_off);
    	trace_ocfs2_add_new_xattr_cluster((unsigned long long)block, num_bits);
    
    	if (bucket_blkno(first) + (prev_clusters * bpc) == block &&
    	    (prev_clusters + num_bits) << osb->s_clustersize_bits <=
    	     OCFS2_MAX_XATTR_TREE_LEAF_SIZE) {
    		/*
    		 * If this cluster is contiguous with the old one and
    		 * adding this new cluster, we don't surpass the limit of
    		 * OCFS2_MAX_XATTR_TREE_LEAF_SIZE, cool. We will let it be
    		 * initialized and used like other buckets in the previous
    		 * cluster.
    		 * So add it as a contiguous one. The caller will handle
    		 * its init process.
    		 */
    		v_start = prev_cpos + prev_clusters;
    		*num_clusters = prev_clusters + num_bits;
    	} else {
    		ret = ocfs2_adjust_xattr_cross_cluster(inode,
    						       handle,
    						       first,
    						       target,
    						       block,
    						       prev_clusters,
    						       &v_start,
    						       extend);
    		if (ret) {
    			mlog_errno(ret);
    			goto leave;
    		}
    	}
    
    	trace_ocfs2_add_new_xattr_cluster_insert((unsigned long long)block,
    						 v_start, num_bits);
    	ret = ocfs2_insert_extent(handle, &et, v_start, block,
    				  num_bits, 0, ctxt->meta_ac);
    	if (ret < 0) {
    		mlog_errno(ret);
    		goto leave;
    	}
    
    	ocfs2_journal_dirty(handle, root_bh);
    
    leave:
    	return ret;
    }
    
    /*
     * We are given an extent.  'first' is the bucket at the very front of
     * the extent.  The extent has space for an additional bucket past
     * bucket_xh(first)->xh_num_buckets.  'target_blkno' is the block number
     * of the target bucket.  We wish to shift every bucket past the target
     * down one, filling in that additional space.  When we get back to the
     * target, we split the target between itself and the now-empty bucket
     * at target+1 (aka, target_blkno + blks_per_bucket).
     */
    static int ocfs2_extend_xattr_bucket(struct inode *inode,
    				     handle_t *handle,
    				     struct ocfs2_xattr_bucket *first,
    				     u64 target_blk,
    				     u32 num_clusters)
    {
    	int ret, credits;
    	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
    	u16 blk_per_bucket = ocfs2_blocks_per_xattr_bucket(inode->i_sb);
    	u64 end_blk;
    	u16 new_bucket = le16_to_cpu(bucket_xh(first)->xh_num_buckets);
    
    	trace_ocfs2_extend_xattr_bucket((unsigned long long)target_blk,
    					(unsigned long long)bucket_blkno(first),
    					num_clusters, new_bucket);
    
    	/* The extent must have room for an additional bucket */
    	BUG_ON(new_bucket >=
    	       (num_clusters * ocfs2_xattr_buckets_per_cluster(osb)));
    
    	/* end_blk points to the last existing bucket */
    	end_blk = bucket_blkno(first) + ((new_bucket - 1) * blk_per_bucket);
    
    	/*
    	 * end_blk is the start of the last existing bucket.
    	 * Thus, (end_blk - target_blk) covers the target bucket and
    	 * every bucket after it up to, but not including, the last
    	 * existing bucket.  Then we add the last existing bucket, the
    	 * new bucket, and the first bucket (3 * blk_per_bucket).
    	 */
    	credits = (end_blk - target_blk) + (3 * blk_per_bucket);
    	ret = ocfs2_extend_trans(handle, credits);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_xattr_bucket_journal_access(handle, first,
    						OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	while (end_blk != target_blk) {
    		ret = ocfs2_cp_xattr_bucket(inode, handle, end_blk,
    					    end_blk + blk_per_bucket, 0);
    		if (ret)
    			goto out;
    		end_blk -= blk_per_bucket;
    	}
    
    	/* Move half of the xattr in target_blkno to the next bucket. */
    	ret = ocfs2_divide_xattr_bucket(inode, handle, target_blk,
    					target_blk + blk_per_bucket, NULL, 0);
    
    	le16_add_cpu(&bucket_xh(first)->xh_num_buckets, 1);
    	ocfs2_xattr_bucket_journal_dirty(handle, first);
    
    out:
    	return ret;
    }
    
    /*
     * Add new xattr bucket in an extent record and adjust the buckets
     * accordingly.  xb_bh is the ocfs2_xattr_block, and target is the
     * bucket we want to insert into.
     *
     * In the easy case, we will move all the buckets after target down by
     * one. Half of target's xattrs will be moved to the next bucket.
     *
     * If current cluster is full, we'll allocate a new one.  This may not
     * be contiguous.  The underlying calls will make sure that there is
     * space for the insert, shifting buckets around if necessary.
     * 'target' may be moved by those calls.
     */
    static int ocfs2_add_new_xattr_bucket(struct inode *inode,
    				      struct buffer_head *xb_bh,
    				      struct ocfs2_xattr_bucket *target,
    				      struct ocfs2_xattr_set_ctxt *ctxt)
    {
    	struct ocfs2_xattr_block *xb =
    			(struct ocfs2_xattr_block *)xb_bh->b_data;
    	struct ocfs2_xattr_tree_root *xb_root = &xb->xb_attrs.xb_root;
    	struct ocfs2_extent_list *el = &xb_root->xt_list;
    	u32 name_hash =
    		le32_to_cpu(bucket_xh(target)->xh_entries[0].xe_name_hash);
    	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
    	int ret, num_buckets, extend = 1;
    	u64 p_blkno;
    	u32 e_cpos, num_clusters;
    	/* The bucket at the front of the extent */
    	struct ocfs2_xattr_bucket *first;
    
    	trace_ocfs2_add_new_xattr_bucket(
    				(unsigned long long)bucket_blkno(target));
    
    	/* The first bucket of the original extent */
    	first = ocfs2_xattr_bucket_new(inode);
    	if (!first) {
    		ret = -ENOMEM;
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_xattr_get_rec(inode, name_hash, &p_blkno, &e_cpos,
    				  &num_clusters, el);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_read_xattr_bucket(first, p_blkno);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	num_buckets = ocfs2_xattr_buckets_per_cluster(osb) * num_clusters;
    	if (num_buckets == le16_to_cpu(bucket_xh(first)->xh_num_buckets)) {
    		/*
    		 * This can move first+target if the target bucket moves
    		 * to the new extent.
    		 */
    		ret = ocfs2_add_new_xattr_cluster(inode,
    						  xb_bh,
    						  first,
    						  target,
    						  &num_clusters,
    						  e_cpos,
    						  &extend,
    						  ctxt);
    		if (ret) {
    			mlog_errno(ret);
    			goto out;
    		}
    	}
    
    	if (extend) {
    		ret = ocfs2_extend_xattr_bucket(inode,
    						ctxt->handle,
    						first,
    						bucket_blkno(target),
    						num_clusters);
    		if (ret)
    			mlog_errno(ret);
    	}
    
    out:
    	ocfs2_xattr_bucket_free(first);
    
    	return ret;
    }
    
    /*
     * Truncate the specified xe_off entry in xattr bucket.
     * bucket is indicated by header_bh and len is the new length.
     * Both the ocfs2_xattr_value_root and the entry will be updated here.
     *
     * Copy the new updated xe and xe_value_root to new_xe and new_xv if needed.
     */
    static int ocfs2_xattr_bucket_value_truncate(struct inode *inode,
    					     struct ocfs2_xattr_bucket *bucket,
    					     int xe_off,
    					     int len,
    					     struct ocfs2_xattr_set_ctxt *ctxt)
    {
    	int ret, offset;
    	u64 value_blk;
    	struct ocfs2_xattr_entry *xe;
    	struct ocfs2_xattr_header *xh = bucket_xh(bucket);
    	size_t blocksize = inode->i_sb->s_blocksize;
    	struct ocfs2_xattr_value_buf vb = {
    		.vb_access = ocfs2_journal_access,
    	};
    
    	xe = &xh->xh_entries[xe_off];
    
    	BUG_ON(!xe || ocfs2_xattr_is_local(xe));
    
    	offset = le16_to_cpu(xe->xe_name_offset) +
    		 OCFS2_XATTR_SIZE(xe->xe_name_len);
    
    	value_blk = offset / blocksize;
    
    	/* We don't allow ocfs2_xattr_value to be stored in different block. */
    	BUG_ON(value_blk != (offset + OCFS2_XATTR_ROOT_SIZE - 1) / blocksize);
    
    	vb.vb_bh = bucket->bu_bhs[value_blk];
    	BUG_ON(!vb.vb_bh);
    
    	vb.vb_xv = (struct ocfs2_xattr_value_root *)
    		(vb.vb_bh->b_data + offset % blocksize);
    
    	/*
    	 * From here on out we have to dirty the bucket.  The generic
    	 * value calls only modify one of the bucket's bhs, but we need
    	 * to send the bucket at once.  So if they error, they *could* have
    	 * modified something.  We have to assume they did, and dirty
    	 * the whole bucket.  This leaves us in a consistent state.
    	 */
    	trace_ocfs2_xattr_bucket_value_truncate(
    			(unsigned long long)bucket_blkno(bucket), xe_off, len);
    	ret = ocfs2_xattr_value_truncate(inode, &vb, len, ctxt);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_xattr_bucket_journal_access(ctxt->handle, bucket,
    						OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	xe->xe_value_size = cpu_to_le64(len);
    
    	ocfs2_xattr_bucket_journal_dirty(ctxt->handle, bucket);
    
    out:
    	return ret;
    }
    
    static int ocfs2_rm_xattr_cluster(struct inode *inode,
    				  struct buffer_head *root_bh,
    				  u64 blkno,
    				  u32 cpos,
    				  u32 len,
    				  void *para)
    {
    	int ret;
    	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
    	struct inode *tl_inode = osb->osb_tl_inode;
    	handle_t *handle;
    	struct ocfs2_xattr_block *xb =
    			(struct ocfs2_xattr_block *)root_bh->b_data;
    	struct ocfs2_alloc_context *meta_ac = NULL;
    	struct ocfs2_cached_dealloc_ctxt dealloc;
    	struct ocfs2_extent_tree et;
    
    	ret = ocfs2_iterate_xattr_buckets(inode, blkno, len,
    					  ocfs2_delete_xattr_in_bucket, para);
    	if (ret) {
    		mlog_errno(ret);
    		return ret;
    	}
    
    	ocfs2_init_xattr_tree_extent_tree(&et, INODE_CACHE(inode), root_bh);
    
    	ocfs2_init_dealloc_ctxt(&dealloc);
    
    	trace_ocfs2_rm_xattr_cluster(
    			(unsigned long long)OCFS2_I(inode)->ip_blkno,
    			(unsigned long long)blkno, cpos, len);
    
    	ocfs2_remove_xattr_clusters_from_cache(INODE_CACHE(inode), blkno,
    					       len);
    
    	ret = ocfs2_lock_allocators(inode, &et, 0, 1, NULL, &meta_ac);
    	if (ret) {
    		mlog_errno(ret);
    		return ret;
    	}
    
    	mutex_lock(&tl_inode->i_mutex);
    
    	if (ocfs2_truncate_log_needs_flush(osb)) {
    		ret = __ocfs2_flush_truncate_log(osb);
    		if (ret < 0) {
    			mlog_errno(ret);
    			goto out;
    		}
    	}
    
    	handle = ocfs2_start_trans(osb, ocfs2_remove_extent_credits(osb->sb));
    	if (IS_ERR(handle)) {
    		ret = -ENOMEM;
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_journal_access_xb(handle, INODE_CACHE(inode), root_bh,
    				      OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret) {
    		mlog_errno(ret);
    		goto out_commit;
    	}
    
    	ret = ocfs2_remove_extent(handle, &et, cpos, len, meta_ac,
    				  &dealloc);
    	if (ret) {
    		mlog_errno(ret);
    		goto out_commit;
    	}
    
    	le32_add_cpu(&xb->xb_attrs.xb_root.xt_clusters, -len);
    	ocfs2_journal_dirty(handle, root_bh);
    
    	ret = ocfs2_truncate_log_append(osb, handle, blkno, len);
    	if (ret)
    		mlog_errno(ret);
    	ocfs2_update_inode_fsync_trans(handle, inode, 0);
    
    out_commit:
    	ocfs2_commit_trans(osb, handle);
    out:
    	ocfs2_schedule_truncate_log_flush(osb, 1);
    
    	mutex_unlock(&tl_inode->i_mutex);
    
    	if (meta_ac)
    		ocfs2_free_alloc_context(meta_ac);
    
    	ocfs2_run_deallocs(osb, &dealloc);
    
    	return ret;
    }
    
    /*
     * check whether the xattr bucket is filled up with the same hash value.
     * If we want to insert the xattr with the same hash, return -ENOSPC.
     * If we want to insert a xattr with different hash value, go ahead
     * and ocfs2_divide_xattr_bucket will handle this.
     */
    static int ocfs2_check_xattr_bucket_collision(struct inode *inode,
    					      struct ocfs2_xattr_bucket *bucket,
    					      const char *name)
    {
    	struct ocfs2_xattr_header *xh = bucket_xh(bucket);
    	u32 name_hash = ocfs2_xattr_name_hash(inode, name, strlen(name));
    
    	if (name_hash != le32_to_cpu(xh->xh_entries[0].xe_name_hash))
    		return 0;
    
    	if (xh->xh_entries[le16_to_cpu(xh->xh_count) - 1].xe_name_hash ==
    	    xh->xh_entries[0].xe_name_hash) {
    		mlog(ML_ERROR, "Too much hash collision in xattr bucket %llu, "
    		     "hash = %u\n",
    		     (unsigned long long)bucket_blkno(bucket),
    		     le32_to_cpu(xh->xh_entries[0].xe_name_hash));
    		return -ENOSPC;
    	}
    
    	return 0;
    }
    
    /*
     * Try to set the entry in the current bucket.  If we fail, the caller
     * will handle getting us another bucket.
     */
    static int ocfs2_xattr_set_entry_bucket(struct inode *inode,
    					struct ocfs2_xattr_info *xi,
    					struct ocfs2_xattr_search *xs,
    					struct ocfs2_xattr_set_ctxt *ctxt)
    {
    	int ret;
    	struct ocfs2_xa_loc loc;
    
    	trace_ocfs2_xattr_set_entry_bucket(xi->xi_name);
    
    	ocfs2_init_xattr_bucket_xa_loc(&loc, xs->bucket,
    				       xs->not_found ? NULL : xs->here);
    	ret = ocfs2_xa_set(&loc, xi, ctxt);
    	if (!ret) {
    		xs->here = loc.xl_entry;
    		goto out;
    	}
    	if (ret != -ENOSPC) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	/* Ok, we need space.  Let's try defragmenting the bucket. */
    	ret = ocfs2_defrag_xattr_bucket(inode, ctxt->handle,
    					xs->bucket);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_xa_set(&loc, xi, ctxt);
    	if (!ret) {
    		xs->here = loc.xl_entry;
    		goto out;
    	}
    	if (ret != -ENOSPC)
    		mlog_errno(ret);
    
    
    out:
    	return ret;
    }
    
    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)
    {
    	int ret;
    
    	trace_ocfs2_xattr_set_entry_index_block(xi->xi_name);
    
    	ret = ocfs2_xattr_set_entry_bucket(inode, xi, xs, ctxt);
    	if (!ret)
    		goto out;
    	if (ret != -ENOSPC) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	/* Ack, need more space.  Let's try to get another bucket! */
    
    	/*
    	 * We do not allow for overlapping ranges between buckets. And
    	 * the maximum number of collisions we will allow for then is
    	 * one bucket's worth, so check it here whether we need to
    	 * add a new bucket for the insert.
    	 */
    	ret = ocfs2_check_xattr_bucket_collision(inode,
    						 xs->bucket,
    						 xi->xi_name);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_add_new_xattr_bucket(inode,
    					 xs->xattr_bh,
    					 xs->bucket,
    					 ctxt);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	/*
    	 * ocfs2_add_new_xattr_bucket() will have updated
    	 * xs->bucket if it moved, but it will not have updated
    	 * any of the other search fields.  Thus, we drop it and
    	 * re-search.  Everything should be cached, so it'll be
    	 * quick.
    	 */
    	ocfs2_xattr_bucket_relse(xs->bucket);
    	ret = ocfs2_xattr_index_block_find(inode, xs->xattr_bh,
    					   xi->xi_name_index,
    					   xi->xi_name, xs);
    	if (ret && ret != -ENODATA)
    		goto out;
    	xs->not_found = ret;
    
    	/* Ok, we have a new bucket, let's try again */
    	ret = ocfs2_xattr_set_entry_bucket(inode, xi, xs, ctxt);
    	if (ret && (ret != -ENOSPC))
    		mlog_errno(ret);
    
    out:
    	return ret;
    }
    
    static int ocfs2_delete_xattr_in_bucket(struct inode *inode,
    					struct ocfs2_xattr_bucket *bucket,
    					void *para)
    {
    	int ret = 0, ref_credits;
    	struct ocfs2_xattr_header *xh = bucket_xh(bucket);
    	u16 i;
    	struct ocfs2_xattr_entry *xe;
    	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
    	struct ocfs2_xattr_set_ctxt ctxt = {NULL, NULL,};
    	int credits = ocfs2_remove_extent_credits(osb->sb) +
    		ocfs2_blocks_per_xattr_bucket(inode->i_sb);
    	struct ocfs2_xattr_value_root *xv;
    	struct ocfs2_rm_xattr_bucket_para *args =
    			(struct ocfs2_rm_xattr_bucket_para *)para;
    
    	ocfs2_init_dealloc_ctxt(&ctxt.dealloc);
    
    	for (i = 0; i < le16_to_cpu(xh->xh_count); i++) {
    		xe = &xh->xh_entries[i];
    		if (ocfs2_xattr_is_local(xe))
    			continue;
    
    		ret = ocfs2_get_xattr_tree_value_root(inode->i_sb, bucket,
    						      i, &xv, NULL);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    		ret = ocfs2_lock_xattr_remove_allocators(inode, xv,
    							 args->ref_ci,
    							 args->ref_root_bh,
    							 &ctxt.meta_ac,
    							 &ref_credits);
    
    		ctxt.handle = ocfs2_start_trans(osb, credits + ref_credits);
    		if (IS_ERR(ctxt.handle)) {
    			ret = PTR_ERR(ctxt.handle);
    			mlog_errno(ret);
    			break;
    		}
    
    		ret = ocfs2_xattr_bucket_value_truncate(inode, bucket,
    							i, 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) {
    			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;
    }
    
    /*
     * Whenever we modify a xattr value root in the bucket(e.g, CoW
     * or change the extent record flag), we need to recalculate
     * the metaecc for the whole bucket. So it is done here.
     *
     * Note:
     * We have to give the extra credits for the caller.
     */
    static int ocfs2_xattr_bucket_post_refcount(struct inode *inode,
    					    handle_t *handle,
    					    void *para)
    {
    	int ret;
    	struct ocfs2_xattr_bucket *bucket =
    			(struct ocfs2_xattr_bucket *)para;
    
    	ret = ocfs2_xattr_bucket_journal_access(handle, bucket,
    						OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret) {
    		mlog_errno(ret);
    		return ret;
    	}
    
    	ocfs2_xattr_bucket_journal_dirty(handle, bucket);
    
    	return 0;
    }
    
    /*
     * Special action we need if the xattr value is refcounted.
     *
     * 1. If the xattr is refcounted, lock the tree.
     * 2. CoW the xattr if we are setting the new value and the value
     *    will be stored outside.
     * 3. In other case, decrease_refcount will work for us, so just
     *    lock the refcount tree, calculate the meta and credits is OK.
     *
     * We have to do CoW before ocfs2_init_xattr_set_ctxt since
     * currently CoW is a completed transaction, while this function
     * will also lock the allocators and let us deadlock. So we will
     * CoW the whole xattr value.
     */
    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_add,
    					int *credits)
    {
    	int ret = 0;
    	struct ocfs2_xattr_block *xb;
    	struct ocfs2_xattr_entry *xe;
    	char *base;
    	u32 p_cluster, num_clusters;
    	unsigned int ext_flags;
    	int name_offset, name_len;
    	struct ocfs2_xattr_value_buf vb;
    	struct ocfs2_xattr_bucket *bucket = NULL;
    	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
    	struct ocfs2_post_refcount refcount;
    	struct ocfs2_post_refcount *p = NULL;
    	struct buffer_head *ref_root_bh = NULL;
    
    	if (!xis->not_found) {
    		xe = xis->here;
    		name_offset = le16_to_cpu(xe->xe_name_offset);
    		name_len = OCFS2_XATTR_SIZE(xe->xe_name_len);
    		base = xis->base;
    		vb.vb_bh = xis->inode_bh;
    		vb.vb_access = ocfs2_journal_access_di;
    	} else {
    		int i, block_off = 0;
    		xb = (struct ocfs2_xattr_block *)xbs->xattr_bh->b_data;
    		xe = xbs->here;
    		name_offset = le16_to_cpu(xe->xe_name_offset);
    		name_len = OCFS2_XATTR_SIZE(xe->xe_name_len);
    		i = xbs->here - xbs->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(xbs->bucket),
    							i, &block_off,
    							&name_offset);
    			if (ret) {
    				mlog_errno(ret);
    				goto out;
    			}
    			base = bucket_block(xbs->bucket, block_off);
    			vb.vb_bh = xbs->bucket->bu_bhs[block_off];
    			vb.vb_access = ocfs2_journal_access;
    
    			if (ocfs2_meta_ecc(osb)) {
    				/*create parameters for ocfs2_post_refcount. */
    				bucket = xbs->bucket;
    				refcount.credits = bucket->bu_blocks;
    				refcount.para = bucket;
    				refcount.func =
    					ocfs2_xattr_bucket_post_refcount;
    				p = &refcount;
    			}
    		} else {
    			base = xbs->base;
    			vb.vb_bh = xbs->xattr_bh;
    			vb.vb_access = ocfs2_journal_access_xb;
    		}
    	}
    
    	if (ocfs2_xattr_is_local(xe))
    		goto out;
    
    	vb.vb_xv = (struct ocfs2_xattr_value_root *)
    				(base + name_offset + name_len);
    
    	ret = ocfs2_xattr_get_clusters(inode, 0, &p_cluster,
    				       &num_clusters, &vb.vb_xv->xr_list,
    				       &ext_flags);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	/*
    	 * We just need to check the 1st extent record, since we always
    	 * CoW the whole xattr. So there shouldn't be a xattr with
    	 * some REFCOUNT extent recs after the 1st one.
    	 */
    	if (!(ext_flags & OCFS2_EXT_REFCOUNTED))
    		goto out;
    
    	ret = ocfs2_lock_refcount_tree(osb, le64_to_cpu(di->i_refcount_loc),
    				       1, ref_tree, &ref_root_bh);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	/*
    	 * If we are deleting the xattr or the new size will be stored inside,
    	 * cool, leave it there, the xattr truncate process will remove them
    	 * for us(it still needs the refcount tree lock and the meta, credits).
    	 * And the worse case is that every cluster truncate will split the
    	 * refcount tree, and make the original extent become 3. So we will need
    	 * 2 * cluster more extent recs at most.
    	 */
    	if (!xi->xi_value || xi->xi_value_len <= OCFS2_XATTR_INLINE_SIZE) {
    
    		ret = ocfs2_refcounted_xattr_delete_need(inode,
    							 &(*ref_tree)->rf_ci,
    							 ref_root_bh, vb.vb_xv,
    							 meta_add, credits);
    		if (ret)
    			mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_refcount_cow_xattr(inode, di, &vb,
    				       *ref_tree, ref_root_bh, 0,
    				       le32_to_cpu(vb.vb_xv->xr_clusters), p);
    	if (ret)
    		mlog_errno(ret);
    
    out:
    	brelse(ref_root_bh);
    	return ret;
    }
    
    /*
     * Add the REFCOUNTED flags for all the extent rec in ocfs2_xattr_value_root.
     * The physical clusters will be added to refcount tree.
     */
    static int ocfs2_xattr_value_attach_refcount(struct inode *inode,
    				struct ocfs2_xattr_value_root *xv,
    				struct ocfs2_extent_tree *value_et,
    				struct ocfs2_caching_info *ref_ci,
    				struct buffer_head *ref_root_bh,
    				struct ocfs2_cached_dealloc_ctxt *dealloc,
    				struct ocfs2_post_refcount *refcount)
    {
    	int ret = 0;
    	u32 clusters = le32_to_cpu(xv->xr_clusters);
    	u32 cpos, p_cluster, num_clusters;
    	struct ocfs2_extent_list *el = &xv->xr_list;
    	unsigned int ext_flags;
    
    	cpos = 0;
    	while (cpos < clusters) {
    		ret = ocfs2_xattr_get_clusters(inode, cpos, &p_cluster,
    					       &num_clusters, el, &ext_flags);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    		cpos += num_clusters;
    		if ((ext_flags & OCFS2_EXT_REFCOUNTED))
    			continue;
    
    		BUG_ON(!p_cluster);
    
    		ret = ocfs2_add_refcount_flag(inode, value_et,
    					      ref_ci, ref_root_bh,
    					      cpos - num_clusters,
    					      p_cluster, num_clusters,
    					      dealloc, refcount);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    	}
    
    	return ret;
    }
    
    /*
     * Given a normal ocfs2_xattr_header, refcount all the entries which
     * have value stored outside.
     * Used for xattrs stored in inode and ocfs2_xattr_block.
     */
    static int ocfs2_xattr_attach_refcount_normal(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,
    				struct ocfs2_cached_dealloc_ctxt *dealloc)
    {
    
    	struct ocfs2_xattr_entry *xe;
    	struct ocfs2_xattr_value_root *xv;
    	struct ocfs2_extent_tree et;
    	int i, ret = 0;
    
    	for (i = 0; i < le16_to_cpu(header->xh_count); i++) {
    		xe = &header->xh_entries[i];
    
    		if (ocfs2_xattr_is_local(xe))
    			continue;
    
    		xv = (struct ocfs2_xattr_value_root *)((void *)header +
    			le16_to_cpu(xe->xe_name_offset) +
    			OCFS2_XATTR_SIZE(xe->xe_name_len));
    
    		vb->vb_xv = xv;
    		ocfs2_init_xattr_value_extent_tree(&et, INODE_CACHE(inode), vb);
    
    		ret = ocfs2_xattr_value_attach_refcount(inode, xv, &et,
    							ref_ci, ref_root_bh,
    							dealloc, NULL);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    	}
    
    	return ret;
    }
    
    static int ocfs2_xattr_inline_attach_refcount(struct inode *inode,
    				struct buffer_head *fe_bh,
    				struct ocfs2_caching_info *ref_ci,
    				struct buffer_head *ref_root_bh,
    				struct ocfs2_cached_dealloc_ctxt *dealloc)
    {
    	struct ocfs2_dinode *di = (struct ocfs2_dinode *)fe_bh->b_data;
    	struct ocfs2_xattr_header *header = (struct ocfs2_xattr_header *)
    				(fe_bh->b_data + inode->i_sb->s_blocksize -
    				le16_to_cpu(di->i_xattr_inline_size));
    	struct ocfs2_xattr_value_buf vb = {
    		.vb_bh = fe_bh,
    		.vb_access = ocfs2_journal_access_di,
    	};
    
    	return ocfs2_xattr_attach_refcount_normal(inode, &vb, header,
    						  ref_ci, ref_root_bh, dealloc);
    }
    
    struct ocfs2_xattr_tree_value_refcount_para {
    	struct ocfs2_caching_info *ref_ci;
    	struct buffer_head *ref_root_bh;
    	struct ocfs2_cached_dealloc_ctxt *dealloc;
    };
    
    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)
    {
    	int ret, block_off, name_offset;
    	struct ocfs2_xattr_header *xh = bucket_xh(bucket);
    	struct ocfs2_xattr_entry *xe = &xh->xh_entries[offset];
    	void *base;
    
    	ret = ocfs2_xattr_bucket_get_name_value(sb,
    						bucket_xh(bucket),
    						offset,
    						&block_off,
    						&name_offset);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	base = bucket_block(bucket, block_off);
    
    	*xv = (struct ocfs2_xattr_value_root *)(base + name_offset +
    			 OCFS2_XATTR_SIZE(xe->xe_name_len));
    
    	if (bh)
    		*bh = bucket->bu_bhs[block_off];
    out:
    	return ret;
    }
    
    /*
     * For a given xattr bucket, refcount all the entries which
     * have value stored outside.
     */
    static int ocfs2_xattr_bucket_value_refcount(struct inode *inode,
    					     struct ocfs2_xattr_bucket *bucket,
    					     void *para)
    {
    	int i, ret = 0;
    	struct ocfs2_extent_tree et;
    	struct ocfs2_xattr_tree_value_refcount_para *ref =
    			(struct ocfs2_xattr_tree_value_refcount_para *)para;
    	struct ocfs2_xattr_header *xh =
    			(struct ocfs2_xattr_header *)bucket->bu_bhs[0]->b_data;
    	struct ocfs2_xattr_entry *xe;
    	struct ocfs2_xattr_value_buf vb = {
    		.vb_access = ocfs2_journal_access,
    	};
    	struct ocfs2_post_refcount refcount = {
    		.credits = bucket->bu_blocks,
    		.para = bucket,
    		.func = ocfs2_xattr_bucket_post_refcount,
    	};
    	struct ocfs2_post_refcount *p = NULL;
    
    	/* We only need post_refcount if we support metaecc. */
    	if (ocfs2_meta_ecc(OCFS2_SB(inode->i_sb)))
    		p = &refcount;
    
    	trace_ocfs2_xattr_bucket_value_refcount(
    				(unsigned long long)bucket_blkno(bucket),
    				le16_to_cpu(xh->xh_count));
    	for (i = 0; i < le16_to_cpu(xh->xh_count); i++) {
    		xe = &xh->xh_entries[i];
    
    		if (ocfs2_xattr_is_local(xe))
    			continue;
    
    		ret = ocfs2_get_xattr_tree_value_root(inode->i_sb, bucket, i,
    						      &vb.vb_xv, &vb.vb_bh);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    		ocfs2_init_xattr_value_extent_tree(&et,
    						   INODE_CACHE(inode), &vb);
    
    		ret = ocfs2_xattr_value_attach_refcount(inode, vb.vb_xv,
    							&et, ref->ref_ci,
    							ref->ref_root_bh,
    							ref->dealloc, p);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    	}
    
    	return ret;
    
    }
    
    static int ocfs2_refcount_xattr_tree_rec(struct inode *inode,
    				     struct buffer_head *root_bh,
    				     u64 blkno, u32 cpos, u32 len, void *para)
    {
    	return ocfs2_iterate_xattr_buckets(inode, blkno, len,
    					   ocfs2_xattr_bucket_value_refcount,
    					   para);
    }
    
    static int ocfs2_xattr_block_attach_refcount(struct inode *inode,
    				struct buffer_head *blk_bh,
    				struct ocfs2_caching_info *ref_ci,
    				struct buffer_head *ref_root_bh,
    				struct ocfs2_cached_dealloc_ctxt *dealloc)
    {
    	int ret = 0;
    	struct ocfs2_xattr_block *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;
    		struct ocfs2_xattr_value_buf vb = {
    			.vb_bh = blk_bh,
    			.vb_access = ocfs2_journal_access_xb,
    		};
    
    		ret = ocfs2_xattr_attach_refcount_normal(inode, &vb, header,
    							 ref_ci, ref_root_bh,
    							 dealloc);
    	} else {
    		struct ocfs2_xattr_tree_value_refcount_para para = {
    			.ref_ci = ref_ci,
    			.ref_root_bh = ref_root_bh,
    			.dealloc = dealloc,
    		};
    
    		ret = ocfs2_iterate_xattr_index_block(inode, blk_bh,
    						ocfs2_refcount_xattr_tree_rec,
    						&para);
    	}
    
    	return ret;
    }
    
    int ocfs2_xattr_attach_refcount_tree(struct inode *inode,
    				     struct buffer_head *fe_bh,
    				     struct ocfs2_caching_info *ref_ci,
    				     struct buffer_head *ref_root_bh,
    				     struct ocfs2_cached_dealloc_ctxt *dealloc)
    {
    	int ret = 0;
    	struct ocfs2_inode_info *oi = OCFS2_I(inode);
    	struct ocfs2_dinode *di = (struct ocfs2_dinode *)fe_bh->b_data;
    	struct buffer_head *blk_bh = NULL;
    
    	if (oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL) {
    		ret = ocfs2_xattr_inline_attach_refcount(inode, fe_bh,
    							 ref_ci, ref_root_bh,
    							 dealloc);
    		if (ret) {
    			mlog_errno(ret);
    			goto out;
    		}
    	}
    
    	if (!di->i_xattr_loc)
    		goto out;
    
    	ret = ocfs2_read_xattr_block(inode, le64_to_cpu(di->i_xattr_loc),
    				     &blk_bh);
    	if (ret < 0) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_xattr_block_attach_refcount(inode, blk_bh, ref_ci,
    						ref_root_bh, dealloc);
    	if (ret)
    		mlog_errno(ret);
    
    	brelse(blk_bh);
    out:
    
    	return ret;
    }
    
    typedef int (should_xattr_reflinked)(struct ocfs2_xattr_entry *xe);
    /*
     * Store the information we need in xattr reflink.
     * old_bh and new_bh are inode bh for the old and new inode.
     */
    struct ocfs2_xattr_reflink {
    	struct inode *old_inode;
    	struct inode *new_inode;
    	struct buffer_head *old_bh;
    	struct buffer_head *new_bh;
    	struct ocfs2_caching_info *ref_ci;
    	struct buffer_head *ref_root_bh;
    	struct ocfs2_cached_dealloc_ctxt *dealloc;
    	should_xattr_reflinked *xattr_reflinked;
    };
    
    /*
     * Given a xattr header and xe offset,
     * return the proper xv and the corresponding bh.
     * xattr in inode, block and xattr tree have different implementaions.
     */
    typedef int (get_xattr_value_root)(struct super_block *sb,
    				   struct buffer_head *bh,
    				   struct ocfs2_xattr_header *xh,
    				   int offset,
    				   struct ocfs2_xattr_value_root **xv,
    				   struct buffer_head **ret_bh,
    				   void *para);
    
    /*
     * Calculate all the xattr value root metadata stored in this xattr header and
     * credits we need if we create them from the scratch.
     * We use get_xattr_value_root so that all types of xattr container can use it.
     */
    static int ocfs2_value_metas_in_xattr_header(struct super_block *sb,
    					     struct buffer_head *bh,
    					     struct ocfs2_xattr_header *xh,
    					     int *metas, int *credits,
    					     int *num_recs,
    					     get_xattr_value_root *func,
    					     void *para)
    {
    	int i, ret = 0;
    	struct ocfs2_xattr_value_root *xv;
    	struct ocfs2_xattr_entry *xe;
    
    	for (i = 0; i < le16_to_cpu(xh->xh_count); i++) {
    		xe = &xh->xh_entries[i];
    		if (ocfs2_xattr_is_local(xe))
    			continue;
    
    		ret = func(sb, bh, xh, i, &xv, NULL, para);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    		*metas += le16_to_cpu(xv->xr_list.l_tree_depth) *
    			  le16_to_cpu(xv->xr_list.l_next_free_rec);
    
    		*credits += ocfs2_calc_extend_credits(sb,
    						&def_xv.xv.xr_list);
    
    		/*
    		 * If the value is a tree with depth > 1, We don't go deep
    		 * to the extent block, so just calculate a maximum record num.
    		 */
    		if (!xv->xr_list.l_tree_depth)
    			*num_recs += le16_to_cpu(xv->xr_list.l_next_free_rec);
    		else
    			*num_recs += ocfs2_clusters_for_bytes(sb,
    							      XATTR_SIZE_MAX);
    	}
    
    	return ret;
    }
    
    /* Used by xattr inode and block to return the right xv and buffer_head. */
    static int ocfs2_get_xattr_value_root(struct super_block *sb,
    				      struct buffer_head *bh,
    				      struct ocfs2_xattr_header *xh,
    				      int offset,
    				      struct ocfs2_xattr_value_root **xv,
    				      struct buffer_head **ret_bh,
    				      void *para)
    {
    	struct ocfs2_xattr_entry *xe = &xh->xh_entries[offset];
    
    	*xv = (struct ocfs2_xattr_value_root *)((void *)xh +
    		le16_to_cpu(xe->xe_name_offset) +
    		OCFS2_XATTR_SIZE(xe->xe_name_len));
    
    	if (ret_bh)
    		*ret_bh = bh;
    
    	return 0;
    }
    
    /*
     * Lock the meta_ac and caculate how much credits we need for reflink xattrs.
     * It is only used for inline xattr and xattr block.
     */
    static int ocfs2_reflink_lock_xattr_allocators(struct ocfs2_super *osb,
    					struct ocfs2_xattr_header *xh,
    					struct buffer_head *ref_root_bh,
    					int *credits,
    					struct ocfs2_alloc_context **meta_ac)
    {
    	int ret, meta_add = 0, num_recs = 0;
    	struct ocfs2_refcount_block *rb =
    			(struct ocfs2_refcount_block *)ref_root_bh->b_data;
    
    	*credits = 0;
    
    	ret = ocfs2_value_metas_in_xattr_header(osb->sb, NULL, xh,
    						&meta_add, credits, &num_recs,
    						ocfs2_get_xattr_value_root,
    						NULL);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	/*
    	 * We need to add/modify num_recs in refcount tree, so just calculate
    	 * an approximate number we need for refcount tree change.
    	 * Sometimes we need to split the tree, and after split,  half recs
    	 * will be moved to the new block, and a new block can only provide
    	 * half number of recs. So we multiple new blocks by 2.
    	 */
    	num_recs = num_recs / ocfs2_refcount_recs_per_rb(osb->sb) * 2;
    	meta_add += num_recs;
    	*credits += num_recs + num_recs * OCFS2_EXPAND_REFCOUNT_TREE_CREDITS;
    	if (le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL)
    		*credits += le16_to_cpu(rb->rf_list.l_tree_depth) *
    			    le16_to_cpu(rb->rf_list.l_next_free_rec) + 1;
    	else
    		*credits += 1;
    
    	ret = ocfs2_reserve_new_metadata_blocks(osb, meta_add, meta_ac);
    	if (ret)
    		mlog_errno(ret);
    
    out:
    	return ret;
    }
    
    /*
     * Given a xattr header, reflink all the xattrs in this container.
     * It can be used for inode, block and bucket.
     *
     * NOTE:
     * Before we call this function, the caller has memcpy the xattr in
     * old_xh to the new_xh.
     *
     * If args.xattr_reflinked is set, call it to decide whether the xe should
     * be reflinked or not. If not, remove it from the new xattr header.
     */
    static int ocfs2_reflink_xattr_header(handle_t *handle,
    				      struct ocfs2_xattr_reflink *args,
    				      struct buffer_head *old_bh,
    				      struct ocfs2_xattr_header *xh,
    				      struct buffer_head *new_bh,
    				      struct ocfs2_xattr_header *new_xh,
    				      struct ocfs2_xattr_value_buf *vb,
    				      struct ocfs2_alloc_context *meta_ac,
    				      get_xattr_value_root *func,
    				      void *para)
    {
    	int ret = 0, i, j;
    	struct super_block *sb = args->old_inode->i_sb;
    	struct buffer_head *value_bh;
    	struct ocfs2_xattr_entry *xe, *last;
    	struct ocfs2_xattr_value_root *xv, *new_xv;
    	struct ocfs2_extent_tree data_et;
    	u32 clusters, cpos, p_cluster, num_clusters;
    	unsigned int ext_flags = 0;
    
    	trace_ocfs2_reflink_xattr_header((unsigned long long)old_bh->b_blocknr,
    					 le16_to_cpu(xh->xh_count));
    
    	last = &new_xh->xh_entries[le16_to_cpu(new_xh->xh_count)];
    	for (i = 0, j = 0; i < le16_to_cpu(xh->xh_count); i++, j++) {
    		xe = &xh->xh_entries[i];
    
    		if (args->xattr_reflinked && !args->xattr_reflinked(xe)) {
    			xe = &new_xh->xh_entries[j];
    
    			le16_add_cpu(&new_xh->xh_count, -1);
    			if (new_xh->xh_count) {
    				memmove(xe, xe + 1,
    					(void *)last - (void *)xe);
    				memset(last, 0,
    				       sizeof(struct ocfs2_xattr_entry));
    			}
    
    			/*
    			 * We don't want j to increase in the next round since
    			 * it is already moved ahead.
    			 */
    			j--;
    			continue;
    		}
    
    		if (ocfs2_xattr_is_local(xe))
    			continue;
    
    		ret = func(sb, old_bh, xh, i, &xv, NULL, para);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    		ret = func(sb, new_bh, new_xh, j, &new_xv, &value_bh, para);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    		/*
    		 * For the xattr which has l_tree_depth = 0, all the extent
    		 * recs have already be copied to the new xh with the
    		 * propriate OCFS2_EXT_REFCOUNTED flag we just need to
    		 * increase the refount count int the refcount tree.
    		 *
    		 * For the xattr which has l_tree_depth > 0, we need
    		 * to initialize it to the empty default value root,
    		 * and then insert the extents one by one.
    		 */
    		if (xv->xr_list.l_tree_depth) {
    			memcpy(new_xv, &def_xv, sizeof(def_xv));
    			vb->vb_xv = new_xv;
    			vb->vb_bh = value_bh;
    			ocfs2_init_xattr_value_extent_tree(&data_et,
    					INODE_CACHE(args->new_inode), vb);
    		}
    
    		clusters = le32_to_cpu(xv->xr_clusters);
    		cpos = 0;
    		while (cpos < clusters) {
    			ret = ocfs2_xattr_get_clusters(args->old_inode,
    						       cpos,
    						       &p_cluster,
    						       &num_clusters,
    						       &xv->xr_list,
    						       &ext_flags);
    			if (ret) {
    				mlog_errno(ret);
    				goto out;
    			}
    
    			BUG_ON(!p_cluster);
    
    			if (xv->xr_list.l_tree_depth) {
    				ret = ocfs2_insert_extent(handle,
    						&data_et, cpos,
    						ocfs2_clusters_to_blocks(
    							args->old_inode->i_sb,
    							p_cluster),
    						num_clusters, ext_flags,
    						meta_ac);
    				if (ret) {
    					mlog_errno(ret);
    					goto out;
    				}
    			}
    
    			ret = ocfs2_increase_refcount(handle, args->ref_ci,
    						      args->ref_root_bh,
    						      p_cluster, num_clusters,
    						      meta_ac, args->dealloc);
    			if (ret) {
    				mlog_errno(ret);
    				goto out;
    			}
    
    			cpos += num_clusters;
    		}
    	}
    
    out:
    	return ret;
    }
    
    static int ocfs2_reflink_xattr_inline(struct ocfs2_xattr_reflink *args)
    {
    	int ret = 0, credits = 0;
    	handle_t *handle;
    	struct ocfs2_super *osb = OCFS2_SB(args->old_inode->i_sb);
    	struct ocfs2_dinode *di = (struct ocfs2_dinode *)args->old_bh->b_data;
    	int inline_size = le16_to_cpu(di->i_xattr_inline_size);
    	int header_off = osb->sb->s_blocksize - inline_size;
    	struct ocfs2_xattr_header *xh = (struct ocfs2_xattr_header *)
    					(args->old_bh->b_data + header_off);
    	struct ocfs2_xattr_header *new_xh = (struct ocfs2_xattr_header *)
    					(args->new_bh->b_data + header_off);
    	struct ocfs2_alloc_context *meta_ac = NULL;
    	struct ocfs2_inode_info *new_oi;
    	struct ocfs2_dinode *new_di;
    	struct ocfs2_xattr_value_buf vb = {
    		.vb_bh = args->new_bh,
    		.vb_access = ocfs2_journal_access_di,
    	};
    
    	ret = ocfs2_reflink_lock_xattr_allocators(osb, xh, args->ref_root_bh,
    						  &credits, &meta_ac);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	handle = ocfs2_start_trans(osb, credits);
    	if (IS_ERR(handle)) {
    		ret = PTR_ERR(handle);
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_journal_access_di(handle, INODE_CACHE(args->new_inode),
    				      args->new_bh, OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret) {
    		mlog_errno(ret);
    		goto out_commit;
    	}
    
    	memcpy(args->new_bh->b_data + header_off,
    	       args->old_bh->b_data + header_off, inline_size);
    
    	new_di = (struct ocfs2_dinode *)args->new_bh->b_data;
    	new_di->i_xattr_inline_size = cpu_to_le16(inline_size);
    
    	ret = ocfs2_reflink_xattr_header(handle, args, args->old_bh, xh,
    					 args->new_bh, new_xh, &vb, meta_ac,
    					 ocfs2_get_xattr_value_root, NULL);
    	if (ret) {
    		mlog_errno(ret);
    		goto out_commit;
    	}
    
    	new_oi = OCFS2_I(args->new_inode);
    	/*
    	 * Adjust extent record count to reserve space for extended attribute.
    	 * Inline data count had been adjusted in ocfs2_duplicate_inline_data().
    	 */
    	if (!(new_oi->ip_dyn_features & OCFS2_INLINE_DATA_FL) &&
    	    !(ocfs2_inode_is_fast_symlink(args->new_inode))) {
    		struct ocfs2_extent_list *el = &new_di->id2.i_list;
    		le16_add_cpu(&el->l_count, -(inline_size /
    					sizeof(struct ocfs2_extent_rec)));
    	}
    	spin_lock(&new_oi->ip_lock);
    	new_oi->ip_dyn_features |= OCFS2_HAS_XATTR_FL | OCFS2_INLINE_XATTR_FL;
    	new_di->i_dyn_features = cpu_to_le16(new_oi->ip_dyn_features);
    	spin_unlock(&new_oi->ip_lock);
    
    	ocfs2_journal_dirty(handle, args->new_bh);
    
    out_commit:
    	ocfs2_commit_trans(osb, handle);
    
    out:
    	if (meta_ac)
    		ocfs2_free_alloc_context(meta_ac);
    	return ret;
    }
    
    static int ocfs2_create_empty_xattr_block(struct inode *inode,
    					  struct buffer_head *fe_bh,
    					  struct buffer_head **ret_bh,
    					  int indexed)
    {
    	int ret;
    	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
    	struct ocfs2_xattr_set_ctxt ctxt;
    
    	memset(&ctxt, 0, sizeof(ctxt));
    	ret = ocfs2_reserve_new_metadata_blocks(osb, 1, &ctxt.meta_ac);
    	if (ret < 0) {
    		mlog_errno(ret);
    		return ret;
    	}
    
    	ctxt.handle = ocfs2_start_trans(osb, OCFS2_XATTR_BLOCK_CREATE_CREDITS);
    	if (IS_ERR(ctxt.handle)) {
    		ret = PTR_ERR(ctxt.handle);
    		mlog_errno(ret);
    		goto out;
    	}
    
    	trace_ocfs2_create_empty_xattr_block(
    				(unsigned long long)fe_bh->b_blocknr, indexed);
    	ret = ocfs2_create_xattr_block(inode, fe_bh, &ctxt, indexed,
    				       ret_bh);
    	if (ret)
    		mlog_errno(ret);
    
    	ocfs2_commit_trans(osb, ctxt.handle);
    out:
    	ocfs2_free_alloc_context(ctxt.meta_ac);
    	return ret;
    }
    
    static int ocfs2_reflink_xattr_block(struct ocfs2_xattr_reflink *args,
    				     struct buffer_head *blk_bh,
    				     struct buffer_head *new_blk_bh)
    {
    	int ret = 0, credits = 0;
    	handle_t *handle;
    	struct ocfs2_inode_info *new_oi = OCFS2_I(args->new_inode);
    	struct ocfs2_dinode *new_di;
    	struct ocfs2_super *osb = OCFS2_SB(args->new_inode->i_sb);
    	int header_off = offsetof(struct ocfs2_xattr_block, xb_attrs.xb_header);
    	struct ocfs2_xattr_block *xb =
    			(struct ocfs2_xattr_block *)blk_bh->b_data;
    	struct ocfs2_xattr_header *xh = &xb->xb_attrs.xb_header;
    	struct ocfs2_xattr_block *new_xb =
    			(struct ocfs2_xattr_block *)new_blk_bh->b_data;
    	struct ocfs2_xattr_header *new_xh = &new_xb->xb_attrs.xb_header;
    	struct ocfs2_alloc_context *meta_ac;
    	struct ocfs2_xattr_value_buf vb = {
    		.vb_bh = new_blk_bh,
    		.vb_access = ocfs2_journal_access_xb,
    	};
    
    	ret = ocfs2_reflink_lock_xattr_allocators(osb, xh, args->ref_root_bh,
    						  &credits, &meta_ac);
    	if (ret) {
    		mlog_errno(ret);
    		return ret;
    	}
    
    	/* One more credits in case we need to add xattr flags in new inode. */
    	handle = ocfs2_start_trans(osb, credits + 1);
    	if (IS_ERR(handle)) {
    		ret = PTR_ERR(handle);
    		mlog_errno(ret);
    		goto out;
    	}
    
    	if (!(new_oi->ip_dyn_features & OCFS2_HAS_XATTR_FL)) {
    		ret = ocfs2_journal_access_di(handle,
    					      INODE_CACHE(args->new_inode),
    					      args->new_bh,
    					      OCFS2_JOURNAL_ACCESS_WRITE);
    		if (ret) {
    			mlog_errno(ret);
    			goto out_commit;
    		}
    	}
    
    	ret = ocfs2_journal_access_xb(handle, INODE_CACHE(args->new_inode),
    				      new_blk_bh, OCFS2_JOURNAL_ACCESS_WRITE);
    	if (ret) {
    		mlog_errno(ret);
    		goto out_commit;
    	}
    
    	memcpy(new_blk_bh->b_data + header_off, blk_bh->b_data + header_off,
    	       osb->sb->s_blocksize - header_off);
    
    	ret = ocfs2_reflink_xattr_header(handle, args, blk_bh, xh,
    					 new_blk_bh, new_xh, &vb, meta_ac,
    					 ocfs2_get_xattr_value_root, NULL);
    	if (ret) {
    		mlog_errno(ret);
    		goto out_commit;
    	}
    
    	ocfs2_journal_dirty(handle, new_blk_bh);
    
    	if (!(new_oi->ip_dyn_features & OCFS2_HAS_XATTR_FL)) {
    		new_di = (struct ocfs2_dinode *)args->new_bh->b_data;
    		spin_lock(&new_oi->ip_lock);
    		new_oi->ip_dyn_features |= OCFS2_HAS_XATTR_FL;
    		new_di->i_dyn_features = cpu_to_le16(new_oi->ip_dyn_features);
    		spin_unlock(&new_oi->ip_lock);
    
    		ocfs2_journal_dirty(handle, args->new_bh);
    	}
    
    out_commit:
    	ocfs2_commit_trans(osb, handle);
    
    out:
    	ocfs2_free_alloc_context(meta_ac);
    	return ret;
    }
    
    struct ocfs2_reflink_xattr_tree_args {
    	struct ocfs2_xattr_reflink *reflink;
    	struct buffer_head *old_blk_bh;
    	struct buffer_head *new_blk_bh;
    	struct ocfs2_xattr_bucket *old_bucket;
    	struct ocfs2_xattr_bucket *new_bucket;
    };
    
    /*
     * NOTE:
     * We have to handle the case that both old bucket and new bucket
     * will call this function to get the right ret_bh.
     * So The caller must give us the right bh.
     */
    static int ocfs2_get_reflink_xattr_value_root(struct super_block *sb,
    					struct buffer_head *bh,
    					struct ocfs2_xattr_header *xh,
    					int offset,
    					struct ocfs2_xattr_value_root **xv,
    					struct buffer_head **ret_bh,
    					void *para)
    {
    	struct ocfs2_reflink_xattr_tree_args *args =
    			(struct ocfs2_reflink_xattr_tree_args *)para;
    	struct ocfs2_xattr_bucket *bucket;
    
    	if (bh == args->old_bucket->bu_bhs[0])
    		bucket = args->old_bucket;
    	else
    		bucket = args->new_bucket;
    
    	return ocfs2_get_xattr_tree_value_root(sb, bucket, offset,
    					       xv, ret_bh);
    }
    
    struct ocfs2_value_tree_metas {
    	int num_metas;
    	int credits;
    	int num_recs;
    };
    
    static int ocfs2_value_tree_metas_in_bucket(struct super_block *sb,
    					struct buffer_head *bh,
    					struct ocfs2_xattr_header *xh,
    					int offset,
    					struct ocfs2_xattr_value_root **xv,
    					struct buffer_head **ret_bh,
    					void *para)
    {
    	struct ocfs2_xattr_bucket *bucket =
    				(struct ocfs2_xattr_bucket *)para;
    
    	return ocfs2_get_xattr_tree_value_root(sb, bucket, offset,
    					       xv, ret_bh);
    }
    
    static int ocfs2_calc_value_tree_metas(struct inode *inode,
    				      struct ocfs2_xattr_bucket *bucket,
    				      void *para)
    {
    	struct ocfs2_value_tree_metas *metas =
    			(struct ocfs2_value_tree_metas *)para;
    	struct ocfs2_xattr_header *xh =
    			(struct ocfs2_xattr_header *)bucket->bu_bhs[0]->b_data;
    
    	/* Add the credits for this bucket first. */
    	metas->credits += bucket->bu_blocks;
    	return ocfs2_value_metas_in_xattr_header(inode->i_sb, bucket->bu_bhs[0],
    					xh, &metas->num_metas,
    					&metas->credits, &metas->num_recs,
    					ocfs2_value_tree_metas_in_bucket,
    					bucket);
    }
    
    /*
     * Given a xattr extent rec starting from blkno and having len clusters,
     * iterate all the buckets calculate how much metadata we need for reflinking
     * all the ocfs2_xattr_value_root and lock the allocators accordingly.
     */
    static int ocfs2_lock_reflink_xattr_rec_allocators(
    				struct ocfs2_reflink_xattr_tree_args *args,
    				struct ocfs2_extent_tree *xt_et,
    				u64 blkno, u32 len, int *credits,
    				struct ocfs2_alloc_context **meta_ac,
    				struct ocfs2_alloc_context **data_ac)
    {
    	int ret, num_free_extents;
    	struct ocfs2_value_tree_metas metas;
    	struct ocfs2_super *osb = OCFS2_SB(args->reflink->old_inode->i_sb);
    	struct ocfs2_refcount_block *rb;
    
    	memset(&metas, 0, sizeof(metas));
    
    	ret = ocfs2_iterate_xattr_buckets(args->reflink->old_inode, blkno, len,
    					  ocfs2_calc_value_tree_metas, &metas);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	*credits = metas.credits;
    
    	/*
    	 * Calculate we need for refcount tree change.
    	 *
    	 * We need to add/modify num_recs in refcount tree, so just calculate
    	 * an approximate number we need for refcount tree change.
    	 * Sometimes we need to split the tree, and after split,  half recs
    	 * will be moved to the new block, and a new block can only provide
    	 * half number of recs. So we multiple new blocks by 2.
    	 * In the end, we have to add credits for modifying the already
    	 * existed refcount block.
    	 */
    	rb = (struct ocfs2_refcount_block *)args->reflink->ref_root_bh->b_data;
    	metas.num_recs =
    		(metas.num_recs + ocfs2_refcount_recs_per_rb(osb->sb) - 1) /
    		 ocfs2_refcount_recs_per_rb(osb->sb) * 2;
    	metas.num_metas += metas.num_recs;
    	*credits += metas.num_recs +
    		    metas.num_recs * OCFS2_EXPAND_REFCOUNT_TREE_CREDITS;
    	if (le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL)
    		*credits += le16_to_cpu(rb->rf_list.l_tree_depth) *
    			    le16_to_cpu(rb->rf_list.l_next_free_rec) + 1;
    	else
    		*credits += 1;
    
    	/* count in the xattr tree change. */
    	num_free_extents = ocfs2_num_free_extents(osb, xt_et);
    	if (num_free_extents < 0) {
    		ret = num_free_extents;
    		mlog_errno(ret);
    		goto out;
    	}
    
    	if (num_free_extents < len)
    		metas.num_metas += ocfs2_extend_meta_needed(xt_et->et_root_el);
    
    	*credits += ocfs2_calc_extend_credits(osb->sb,
    					      xt_et->et_root_el);
    
    	if (metas.num_metas) {
    		ret = ocfs2_reserve_new_metadata_blocks(osb, metas.num_metas,
    							meta_ac);
    		if (ret) {
    			mlog_errno(ret);
    			goto out;
    		}
    	}
    
    	if (len) {
    		ret = ocfs2_reserve_clusters(osb, len, data_ac);
    		if (ret)
    			mlog_errno(ret);
    	}
    out:
    	if (ret) {
    		if (*meta_ac) {
    			ocfs2_free_alloc_context(*meta_ac);
    			*meta_ac = NULL;
    		}
    	}
    
    	return ret;
    }
    
    static int ocfs2_reflink_xattr_bucket(handle_t *handle,
    				u64 blkno, u64 new_blkno, u32 clusters,
    				u32 *cpos, int num_buckets,
    				struct ocfs2_alloc_context *meta_ac,
    				struct ocfs2_alloc_context *data_ac,
    				struct ocfs2_reflink_xattr_tree_args *args)
    {
    	int i, j, ret = 0;
    	struct super_block *sb = args->reflink->old_inode->i_sb;
    	int bpb = args->old_bucket->bu_blocks;
    	struct ocfs2_xattr_value_buf vb = {
    		.vb_access = ocfs2_journal_access,
    	};
    
    	for (i = 0; i < num_buckets; i++, blkno += bpb, new_blkno += bpb) {
    		ret = ocfs2_read_xattr_bucket(args->old_bucket, blkno);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    		ret = ocfs2_init_xattr_bucket(args->new_bucket, new_blkno, 1);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    		ret = ocfs2_xattr_bucket_journal_access(handle,
    						args->new_bucket,
    						OCFS2_JOURNAL_ACCESS_CREATE);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    		for (j = 0; j < bpb; j++)
    			memcpy(bucket_block(args->new_bucket, j),
    			       bucket_block(args->old_bucket, j),
    			       sb->s_blocksize);
    
    		/*
    		 * Record the start cpos so that we can use it to initialize
    		 * our xattr tree we also set the xh_num_bucket for the new
    		 * bucket.
    		 */
    		if (i == 0) {
    			*cpos = le32_to_cpu(bucket_xh(args->new_bucket)->
    					    xh_entries[0].xe_name_hash);
    			bucket_xh(args->new_bucket)->xh_num_buckets =
    				cpu_to_le16(num_buckets);
    		}
    
    		ocfs2_xattr_bucket_journal_dirty(handle, args->new_bucket);
    
    		ret = ocfs2_reflink_xattr_header(handle, args->reflink,
    					args->old_bucket->bu_bhs[0],
    					bucket_xh(args->old_bucket),
    					args->new_bucket->bu_bhs[0],
    					bucket_xh(args->new_bucket),
    					&vb, meta_ac,
    					ocfs2_get_reflink_xattr_value_root,
    					args);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    		/*
    		 * Re-access and dirty the bucket to calculate metaecc.
    		 * Because we may extend the transaction in reflink_xattr_header
    		 * which will let the already accessed block gone.
    		 */
    		ret = ocfs2_xattr_bucket_journal_access(handle,
    						args->new_bucket,
    						OCFS2_JOURNAL_ACCESS_WRITE);
    		if (ret) {
    			mlog_errno(ret);
    			break;
    		}
    
    		ocfs2_xattr_bucket_journal_dirty(handle, args->new_bucket);
    
    		ocfs2_xattr_bucket_relse(args->old_bucket);
    		ocfs2_xattr_bucket_relse(args->new_bucket);
    	}
    
    	ocfs2_xattr_bucket_relse(args->old_bucket);
    	ocfs2_xattr_bucket_relse(args->new_bucket);
    	return ret;
    }
    
    static int ocfs2_reflink_xattr_buckets(handle_t *handle,
    				struct inode *inode,
    				struct ocfs2_reflink_xattr_tree_args *args,
    				struct ocfs2_extent_tree *et,
    				struct ocfs2_alloc_context *meta_ac,
    				struct ocfs2_alloc_context *data_ac,
    				u64 blkno, u32 cpos, u32 len)
    {
    	int ret, first_inserted = 0;
    	u32 p_cluster, num_clusters, reflink_cpos = 0;
    	u64 new_blkno;
    	unsigned int num_buckets, reflink_buckets;
    	unsigned int bpc =
    		ocfs2_xattr_buckets_per_cluster(OCFS2_SB(inode->i_sb));
    
    	ret = ocfs2_read_xattr_bucket(args->old_bucket, blkno);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    	num_buckets = le16_to_cpu(bucket_xh(args->old_bucket)->xh_num_buckets);
    	ocfs2_xattr_bucket_relse(args->old_bucket);
    
    	while (len && num_buckets) {
    		ret = ocfs2_claim_clusters(handle, data_ac,
    					   1, &p_cluster, &num_clusters);
    		if (ret) {
    			mlog_errno(ret);
    			goto out;
    		}
    
    		new_blkno = ocfs2_clusters_to_blocks(inode->i_sb, p_cluster);
    		reflink_buckets = min(num_buckets, bpc * num_clusters);
    
    		ret = ocfs2_reflink_xattr_bucket(handle, blkno,
    						 new_blkno, num_clusters,
    						 &reflink_cpos, reflink_buckets,
    						 meta_ac, data_ac, args);
    		if (ret) {
    			mlog_errno(ret);
    			goto out;
    		}
    
    		/*
    		 * For the 1st allocated cluster, we make it use the same cpos
    		 * so that the xattr tree looks the same as the original one
    		 * in the most case.
    		 */
    		if (!first_inserted) {
    			reflink_cpos = cpos;
    			first_inserted = 1;
    		}
    		ret = ocfs2_insert_extent(handle, et, reflink_cpos, new_blkno,
    					  num_clusters, 0, meta_ac);
    		if (ret)
    			mlog_errno(ret);
    
    		trace_ocfs2_reflink_xattr_buckets((unsigned long long)new_blkno,
    						  num_clusters, reflink_cpos);
    
    		len -= num_clusters;
    		blkno += ocfs2_clusters_to_blocks(inode->i_sb, num_clusters);
    		num_buckets -= reflink_buckets;
    	}
    out:
    	return ret;
    }
    
    /*
     * Create the same xattr extent record in the new inode's xattr tree.
     */
    static int ocfs2_reflink_xattr_rec(struct inode *inode,
    				   struct buffer_head *root_bh,
    				   u64 blkno,
    				   u32 cpos,
    				   u32 len,
    				   void *para)
    {
    	int ret, credits = 0;
    	handle_t *handle;
    	struct ocfs2_reflink_xattr_tree_args *args =
    			(struct ocfs2_reflink_xattr_tree_args *)para;
    	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
    	struct ocfs2_alloc_context *meta_ac = NULL;
    	struct ocfs2_alloc_context *data_ac = NULL;
    	struct ocfs2_extent_tree et;
    
    	trace_ocfs2_reflink_xattr_rec((unsigned long long)blkno, len);
    
    	ocfs2_init_xattr_tree_extent_tree(&et,
    					  INODE_CACHE(args->reflink->new_inode),
    					  args->new_blk_bh);
    
    	ret = ocfs2_lock_reflink_xattr_rec_allocators(args, &et, blkno,
    						      len, &credits,
    						      &meta_ac, &data_ac);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	handle = ocfs2_start_trans(osb, credits);
    	if (IS_ERR(handle)) {
    		ret = PTR_ERR(handle);
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_reflink_xattr_buckets(handle, inode, args, &et,
    					  meta_ac, data_ac,
    					  blkno, cpos, len);
    	if (ret)
    		mlog_errno(ret);
    
    	ocfs2_commit_trans(osb, handle);
    
    out:
    	if (meta_ac)
    		ocfs2_free_alloc_context(meta_ac);
    	if (data_ac)
    		ocfs2_free_alloc_context(data_ac);
    	return ret;
    }
    
    /*
     * Create reflinked xattr buckets.
     * We will add bucket one by one, and refcount all the xattrs in the bucket
     * if they are stored outside.
     */
    static int ocfs2_reflink_xattr_tree(struct ocfs2_xattr_reflink *args,
    				    struct buffer_head *blk_bh,
    				    struct buffer_head *new_blk_bh)
    {
    	int ret;
    	struct ocfs2_reflink_xattr_tree_args para;
    
    	memset(&para, 0, sizeof(para));
    	para.reflink = args;
    	para.old_blk_bh = blk_bh;
    	para.new_blk_bh = new_blk_bh;
    
    	para.old_bucket = ocfs2_xattr_bucket_new(args->old_inode);
    	if (!para.old_bucket) {
    		mlog_errno(-ENOMEM);
    		return -ENOMEM;
    	}
    
    	para.new_bucket = ocfs2_xattr_bucket_new(args->new_inode);
    	if (!para.new_bucket) {
    		ret = -ENOMEM;
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ret = ocfs2_iterate_xattr_index_block(args->old_inode, blk_bh,
    					      ocfs2_reflink_xattr_rec,
    					      &para);
    	if (ret)
    		mlog_errno(ret);
    
    out:
    	ocfs2_xattr_bucket_free(para.old_bucket);
    	ocfs2_xattr_bucket_free(para.new_bucket);
    	return ret;
    }
    
    static int ocfs2_reflink_xattr_in_block(struct ocfs2_xattr_reflink *args,
    					struct buffer_head *blk_bh)
    {
    	int ret, indexed = 0;
    	struct buffer_head *new_blk_bh = NULL;
    	struct ocfs2_xattr_block *xb =
    			(struct ocfs2_xattr_block *)blk_bh->b_data;
    
    
    	if (le16_to_cpu(xb->xb_flags) & OCFS2_XATTR_INDEXED)
    		indexed = 1;
    
    	ret = ocfs2_create_empty_xattr_block(args->new_inode, args->new_bh,
    					     &new_blk_bh, indexed);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	if (!indexed)
    		ret = ocfs2_reflink_xattr_block(args, blk_bh, new_blk_bh);
    	else
    		ret = ocfs2_reflink_xattr_tree(args, blk_bh, new_blk_bh);
    	if (ret)
    		mlog_errno(ret);
    
    out:
    	brelse(new_blk_bh);
    	return ret;
    }
    
    static int ocfs2_reflink_xattr_no_security(struct ocfs2_xattr_entry *xe)
    {
    	int type = ocfs2_xattr_get_type(xe);
    
    	return type != OCFS2_XATTR_INDEX_SECURITY &&
    	       type != OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS &&
    	       type != OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT;
    }
    
    int ocfs2_reflink_xattrs(struct inode *old_inode,
    			 struct buffer_head *old_bh,
    			 struct inode *new_inode,
    			 struct buffer_head *new_bh,
    			 bool preserve_security)
    {
    	int ret;
    	struct ocfs2_xattr_reflink args;
    	struct ocfs2_inode_info *oi = OCFS2_I(old_inode);
    	struct ocfs2_dinode *di = (struct ocfs2_dinode *)old_bh->b_data;
    	struct buffer_head *blk_bh = NULL;
    	struct ocfs2_cached_dealloc_ctxt dealloc;
    	struct ocfs2_refcount_tree *ref_tree;
    	struct buffer_head *ref_root_bh = NULL;
    
    	ret = ocfs2_lock_refcount_tree(OCFS2_SB(old_inode->i_sb),
    				       le64_to_cpu(di->i_refcount_loc),
    				       1, &ref_tree, &ref_root_bh);
    	if (ret) {
    		mlog_errno(ret);
    		goto out;
    	}
    
    	ocfs2_init_dealloc_ctxt(&dealloc);
    
    	args.old_inode = old_inode;
    	args.new_inode = new_inode;
    	args.old_bh = old_bh;
    	args.new_bh = new_bh;
    	args.ref_ci = &ref_tree->rf_ci;
    	args.ref_root_bh = ref_root_bh;
    	args.dealloc = &dealloc;
    	if (preserve_security)
    		args.xattr_reflinked = NULL;
    	else
    		args.xattr_reflinked = ocfs2_reflink_xattr_no_security;
    
    	if (oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL) {
    		ret = ocfs2_reflink_xattr_inline(&args);
    		if (ret) {
    			mlog_errno(ret);
    			goto out_unlock;
    		}
    	}
    
    	if (!di->i_xattr_loc)
    		goto out_unlock;
    
    	ret = ocfs2_read_xattr_block(old_inode, le64_to_cpu(di->i_xattr_loc),
    				     &blk_bh);
    	if (ret < 0) {
    		mlog_errno(ret);
    		goto out_unlock;
    	}
    
    	ret = ocfs2_reflink_xattr_in_block(&args, blk_bh);
    	if (ret)
    		mlog_errno(ret);
    
    	brelse(blk_bh);
    
    out_unlock:
    	ocfs2_unlock_refcount_tree(OCFS2_SB(old_inode->i_sb),
    				   ref_tree, 1);
    	brelse(ref_root_bh);
    
    	if (ocfs2_dealloc_has_cluster(&dealloc)) {
    		ocfs2_schedule_truncate_log_flush(OCFS2_SB(old_inode->i_sb), 1);
    		ocfs2_run_deallocs(OCFS2_SB(old_inode->i_sb), &dealloc);
    	}
    
    out:
    	return ret;
    }
    
    /*
     * Initialize security and acl for a already created inode.
     * Used for reflink a non-preserve-security file.
     *
     * It uses common api like ocfs2_xattr_set, so the caller
     * must not hold any lock expect i_mutex.
     */
    int ocfs2_init_security_and_acl(struct inode *dir,
    				struct inode *inode,
    				const struct qstr *qstr,
    				struct posix_acl *default_acl,
    				struct posix_acl *acl)
    {
    	struct buffer_head *dir_bh = NULL;
    	int ret = 0;
    
    	ret = ocfs2_init_security_get(inode, dir, qstr, NULL);
    	if (ret) {
    		mlog_errno(ret);
    		goto leave;
    	}
    
    	ret = ocfs2_inode_lock(dir, &dir_bh, 0);
    	if (ret) {
    		mlog_errno(ret);
    		goto leave;
    	}
    
    	if (!ret && default_acl)
    		ret = ocfs2_iop_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
    	if (!ret && acl)
    		ret = ocfs2_iop_set_acl(inode, acl, ACL_TYPE_ACCESS);
    
    	ocfs2_inode_unlock(dir, 0);
    	brelse(dir_bh);
    leave:
    	return ret;
    }
    /*
     * 'security' attributes support
     */
    static size_t ocfs2_xattr_security_list(struct dentry *dentry, char *list,
    					size_t list_size, const char *name,
    					size_t name_len, int type)
    {
    	const size_t prefix_len = XATTR_SECURITY_PREFIX_LEN;
    	const size_t total_len = prefix_len + name_len + 1;
    
    	if (list && total_len <= list_size) {
    		memcpy(list, XATTR_SECURITY_PREFIX, prefix_len);
    		memcpy(list + prefix_len, name, name_len);
    		list[prefix_len + name_len] = '\0';
    	}
    	return total_len;
    }
    
    static int ocfs2_xattr_security_get(struct dentry *dentry, const char *name,
    				    void *buffer, size_t size, int type)
    {
    	if (strcmp(name, "") == 0)
    		return -EINVAL;
    	return ocfs2_xattr_get(dentry->d_inode, OCFS2_XATTR_INDEX_SECURITY,
    			       name, buffer, size);
    }
    
    static int ocfs2_xattr_security_set(struct dentry *dentry, const char *name,
    		const void *value, size_t size, int flags, int type)
    {
    	if (strcmp(name, "") == 0)
    		return -EINVAL;
    
    	return ocfs2_xattr_set(dentry->d_inode, OCFS2_XATTR_INDEX_SECURITY,
    			       name, value, size, flags);
    }
    
    int ocfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
    		     void *fs_info)
    {
    	const struct xattr *xattr;
    	int err = 0;
    
    	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
    		err = ocfs2_xattr_set(inode, OCFS2_XATTR_INDEX_SECURITY,
    				      xattr->name, xattr->value,
    				      xattr->value_len, XATTR_CREATE);
    		if (err)
    			break;
    	}
    	return err;
    }
    
    int ocfs2_init_security_get(struct inode *inode,
    			    struct inode *dir,
    			    const struct qstr *qstr,
    			    struct ocfs2_security_xattr_info *si)
    {
    	/* check whether ocfs2 support feature xattr */
    	if (!ocfs2_supports_xattr(OCFS2_SB(dir->i_sb)))
    		return -EOPNOTSUPP;
    	if (si)
    		return security_old_inode_init_security(inode, dir, qstr,
    							&si->name, &si->value,
    							&si->value_len);
    
    	return security_inode_init_security(inode, dir, qstr,
    					    &ocfs2_initxattrs, NULL);
    }
    
    int ocfs2_init_security_set(handle_t *handle,
    			    struct inode *inode,
    			    struct buffer_head *di_bh,
    			    struct ocfs2_security_xattr_info *si,
    			    struct ocfs2_alloc_context *xattr_ac,
    			    struct ocfs2_alloc_context *data_ac)
    {
    	return ocfs2_xattr_set_handle(handle, inode, di_bh,
    				     OCFS2_XATTR_INDEX_SECURITY,
    				     si->name, si->value, si->value_len, 0,
    				     xattr_ac, data_ac);
    }
    
    const struct xattr_handler ocfs2_xattr_security_handler = {
    	.prefix	= XATTR_SECURITY_PREFIX,
    	.list	= ocfs2_xattr_security_list,
    	.get	= ocfs2_xattr_security_get,
    	.set	= ocfs2_xattr_security_set,
    };
    
    /*
     * 'trusted' attributes support
     */
    static size_t ocfs2_xattr_trusted_list(struct dentry *dentry, char *list,
    				       size_t list_size, const char *name,
    				       size_t name_len, int type)
    {
    	const size_t prefix_len = XATTR_TRUSTED_PREFIX_LEN;
    	const size_t total_len = prefix_len + name_len + 1;
    
    	if (list && total_len <= list_size) {
    		memcpy(list, XATTR_TRUSTED_PREFIX, prefix_len);
    		memcpy(list + prefix_len, name, name_len);
    		list[prefix_len + name_len] = '\0';
    	}
    	return total_len;
    }
    
    static int ocfs2_xattr_trusted_get(struct dentry *dentry, const char *name,
    		void *buffer, size_t size, int type)
    {
    	if (strcmp(name, "") == 0)
    		return -EINVAL;
    	return ocfs2_xattr_get(dentry->d_inode, OCFS2_XATTR_INDEX_TRUSTED,
    			       name, buffer, size);
    }
    
    static int ocfs2_xattr_trusted_set(struct dentry *dentry, const char *name,
    		const void *value, size_t size, int flags, int type)
    {
    	if (strcmp(name, "") == 0)
    		return -EINVAL;
    
    	return ocfs2_xattr_set(dentry->d_inode, OCFS2_XATTR_INDEX_TRUSTED,
    			       name, value, size, flags);
    }
    
    const struct xattr_handler ocfs2_xattr_trusted_handler = {
    	.prefix	= XATTR_TRUSTED_PREFIX,
    	.list	= ocfs2_xattr_trusted_list,
    	.get	= ocfs2_xattr_trusted_get,
    	.set	= ocfs2_xattr_trusted_set,
    };
    
    /*
     * 'user' attributes support
     */
    static size_t ocfs2_xattr_user_list(struct dentry *dentry, char *list,
    				    size_t list_size, const char *name,
    				    size_t name_len, int type)
    {
    	const size_t prefix_len = XATTR_USER_PREFIX_LEN;
    	const size_t total_len = prefix_len + name_len + 1;
    	struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
    
    	if (osb->s_mount_opt & OCFS2_MOUNT_NOUSERXATTR)
    		return 0;
    
    	if (list && total_len <= list_size) {
    		memcpy(list, XATTR_USER_PREFIX, prefix_len);
    		memcpy(list + prefix_len, name, name_len);
    		list[prefix_len + name_len] = '\0';
    	}
    	return total_len;
    }
    
    static int ocfs2_xattr_user_get(struct dentry *dentry, const char *name,
    		void *buffer, size_t size, int type)
    {
    	struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
    
    	if (strcmp(name, "") == 0)
    		return -EINVAL;
    	if (osb->s_mount_opt & OCFS2_MOUNT_NOUSERXATTR)
    		return -EOPNOTSUPP;
    	return ocfs2_xattr_get(dentry->d_inode, OCFS2_XATTR_INDEX_USER, name,
    			       buffer, size);
    }
    
    static int ocfs2_xattr_user_set(struct dentry *dentry, const char *name,
    		const void *value, size_t size, int flags, int type)
    {
    	struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
    
    	if (strcmp(name, "") == 0)
    		return -EINVAL;
    	if (osb->s_mount_opt & OCFS2_MOUNT_NOUSERXATTR)
    		return -EOPNOTSUPP;
    
    	return ocfs2_xattr_set(dentry->d_inode, OCFS2_XATTR_INDEX_USER,
    			       name, value, size, flags);
    }
    
    const struct xattr_handler ocfs2_xattr_user_handler = {
    	.prefix	= XATTR_USER_PREFIX,
    	.list	= ocfs2_xattr_user_list,
    	.get	= ocfs2_xattr_user_get,
    	.set	= ocfs2_xattr_user_set,
    };