[2/2] Large EAs

Signed-off-by: Kalpak Shah <kalpak.shah@sun.com>
Signed-off-by: Andreas Dilger <adilger@sun.com>

Index: linux-2.6.27/fs/ext4/xattr.c
===================================================================
--- linux-2.6.27.orig/fs/ext4/xattr.c
+++ linux-2.6.27/fs/ext4/xattr.c
@@ -168,19 +168,27 @@  ext4_xattr_check_block(struct buffer_hea
 }
 
 static inline int
-ext4_xattr_check_entry(struct ext4_xattr_entry *entry, size_t size)
+ext4_xattr_check_entry(struct ext4_xattr_entry *entry, size_t size,
+		       struct inode *inode)
 {
 	size_t value_size = le32_to_cpu(entry->e_value_size);
 
-	if (entry->e_value_block != 0 || value_size > size ||
-	    le16_to_cpu(entry->e_value_offs) + value_size > size)
+	if ((entry->e_value_inum == 0) &&
+	    (value_size > size ||
+	     le16_to_cpu(entry->e_value_offs) + value_size > size))
+		return -EIO;
+	if (entry->e_value_inum &&
+	    (entry->e_value_inum < le32_to_cpu(EXT4_FIRST_INO(inode->i_sb)) ||
+	     entry->e_value_inum > le32_to_cpu(EXT4_SB(inode->i_sb)->
+							s_es->s_inodes_count)))
 		return -EIO;
 	return 0;
 }
 
 static int
 ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index,
-		      const char *name, size_t size, int sorted)
+		      const char *name, size_t size, int sorted,
+		      struct inode *inode)
 {
 	struct ext4_xattr_entry *entry;
 	size_t name_len;
@@ -200,11 +208,103 @@  ext4_xattr_find_entry(struct ext4_xattr_
 			break;
 	}
 	*pentry = entry;
-	if (!cmp && ext4_xattr_check_entry(entry, size))
+	if (!cmp && ext4_xattr_check_entry(entry, size, inode))
 			return -EIO;
 	return cmp ? -ENODATA : 0;
 }
 
+/*
+ * Read the EA value from an inode.
+ */
+static int
+ext4_xattr_inode_read(struct inode *ea_inode, void *buf, size_t *size)
+{
+	unsigned long block = 0;
+	struct buffer_head *bh = NULL;
+	int err, blocksize;
+	size_t csize, ret_size = 0;
+
+	if (*size == 0 && ea_inode->i_size == 0)
+		return 0;
+
+	blocksize = ea_inode->i_sb->s_blocksize;
+
+	while (ret_size < *size) {
+		csize = (*size - ret_size) > blocksize ? blocksize :
+							*size - ret_size;
+		bh = ext4_bread(NULL, ea_inode, block, 0, &err);
+		if (!bh)
+			return err;
+
+		memcpy(buf, bh->b_data, csize);
+		brelse(bh);
+
+		buf += csize;
+		block += 1;
+		ret_size += csize;
+	}
+
+	*size = ret_size;
+
+	return err;
+}
+
+struct inode *ext4_xattr_inode_iget(struct inode *parent, int ea_ino, int *err)
+{
+	struct inode *ea_inode = NULL;
+
+	ea_inode = ext4_iget(parent->i_sb, ea_ino);
+	if (ea_inode == NULL || is_bad_inode(ea_inode)) {
+		ext4_error(parent->i_sb, __func__,
+			   "error while reading EA inode %d", ea_ino);
+		*err = -EIO;
+		return NULL;
+	}
+
+	if (ea_inode->i_xattr_inode_parent != parent->i_ino ||
+	    ea_inode->i_generation != parent->i_generation) {
+		ext4_error(parent->i_sb, __func__,
+			   "Backpointer from EA inode %d to parent invalid.",
+			   ea_ino);
+		*err = -EINVAL;
+		goto error;
+	}
+
+	if (!(EXT4_I(ea_inode)->i_flags & EXT4_EA_INODE_FL)) {
+		ext4_error(parent->i_sb, __func__, "EA inode %d does not "
+			   "have EXT4_EA_INODE_FL flag set.\n", ea_ino);
+		*err = -EINVAL;
+		goto error;
+	}
+
+	*err = 0;
+	return ea_inode;
+
+error:
+	iput(ea_inode);
+	return NULL;
+}
+
+/*
+ * Read the value from the EA inode.
+ */
+static int
+ext4_xattr_inode_get(struct inode *inode, int ea_ino, void *buffer,
+		     size_t *size)
+{
+	struct inode *ea_inode = NULL;
+	int err;
+
+	ea_inode = ext4_xattr_inode_iget(inode, ea_ino, &err);
+	if (err)
+		return err;
+
+	err = ext4_xattr_inode_read(ea_inode, buffer, size);
+	iput(ea_inode);
+
+	return err;
+}
+
 static int
 ext4_xattr_block_get(struct inode *inode, int name_index, const char *name,
 		     void *buffer, size_t buffer_size)
@@ -235,7 +335,8 @@  bad_block:	ext4_error(inode->i_sb, __fun
 	}
 	ext4_xattr_cache_insert(bh);
 	entry = BFIRST(bh);
-	error = ext4_xattr_find_entry(&entry, name_index, name, bh->b_size, 1);
+	error = ext4_xattr_find_entry(&entry, name_index, name, bh->b_size, 1,
+				      inode);
 	if (error == -EIO)
 		goto bad_block;
 	if (error)
@@ -245,8 +346,16 @@  bad_block:	ext4_error(inode->i_sb, __fun
 		error = -ERANGE;
 		if (size > buffer_size)
 			goto cleanup;
-		memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs),
-		       size);
+		if (entry->e_value_inum) {
+			error = ext4_xattr_inode_get(inode,
+					     le32_to_cpu(entry->e_value_inum),
+					     buffer, &size);
+			if (error)
+				goto cleanup;
+		} else {
+			memcpy(buffer, bh->b_data +
+			       le16_to_cpu(entry->e_value_offs), size);
+		}
 	}
 	error = size;
 
@@ -280,7 +389,7 @@  ext4_xattr_ibody_get(struct inode *inode
 	if (error)
 		goto cleanup;
 	error = ext4_xattr_find_entry(&entry, name_index, name,
-				      end - (void *)entry, 0);
+				      end - (void *)entry, 0, inode);
 	if (error)
 		goto cleanup;
 	size = le32_to_cpu(entry->e_value_size);
@@ -288,8 +397,16 @@  ext4_xattr_ibody_get(struct inode *inode
 		error = -ERANGE;
 		if (size > buffer_size)
 			goto cleanup;
-		memcpy(buffer, (void *)IFIRST(header) +
-		       le16_to_cpu(entry->e_value_offs), size);
+		if (entry->e_value_inum) {
+			error = ext4_xattr_inode_get(inode,
+					     le32_to_cpu(entry->e_value_inum),
+					     buffer, &size);
+			if (error)
+				goto cleanup;
+		} else {
+			memcpy(buffer, (void *)IFIRST(header) +
+			       le16_to_cpu(entry->e_value_offs), size);
+		}
 	}
 	error = size;
 
@@ -511,7 +628,7 @@  static size_t ext4_xattr_free_space(stru
 {
 	for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
 		*total += EXT4_XATTR_LEN(last->e_name_len);
-		if (!last->e_value_block && last->e_value_size) {
+		if (!last->e_value_inum && last->e_value_size) {
 			size_t offs = le16_to_cpu(last->e_value_offs);
 			if (offs < *min_offs)
 				*min_offs = offs;
@@ -520,6 +637,149 @@  static size_t ext4_xattr_free_space(stru
 	return (*min_offs - ((void *)last - base) - sizeof(__u32));
 }
 
+/*
+ * Write the value of the EA in an inode.
+ */
+static int
+ext4_xattr_inode_write(handle_t *handle, struct inode *ea_inode,
+		       const void *buf, int bufsize)
+{
+	struct buffer_head *bh = NULL, dummy;
+	unsigned long block = 0;
+	unsigned blocksize = ea_inode->i_sb->s_blocksize;
+	unsigned max_blocks = (bufsize + blocksize - 1) >> ea_inode->i_blkbits;
+	int csize, wsize = 0;
+	int ret = 0;
+	int retries = 0;
+
+retry:
+	while (ret >= 0 && ret < max_blocks) {
+		block += ret;
+		max_blocks -= ret;
+
+		ret = ext4_get_blocks_wrap(handle, ea_inode, block, max_blocks,
+					   &dummy, 1, 1, 0);
+		if (ret <= 0) {
+			ext4_mark_inode_dirty(handle, ea_inode);
+			if (ret == -ENOSPC &&
+			    ext4_should_retry_alloc(ea_inode->i_sb, &retries)) {
+				ret = 0;
+				goto retry;
+			}
+			break;
+		}
+	}
+
+	block = 0;
+	while (wsize < bufsize) {
+		if (bh != NULL)
+			brelse(bh);
+		csize = (bufsize - wsize) > blocksize ? blocksize :
+								bufsize - wsize;
+		bh = ext4_getblk(handle, ea_inode, block, 0, &ret);
+		if (!bh)
+			goto out;
+		ret = ext4_journal_get_write_access(handle, bh);
+		if (ret)
+			goto out;
+
+		memcpy(bh->b_data, buf, csize);
+		set_buffer_uptodate(bh);
+		ext4_journal_dirty_metadata(handle, bh);
+
+		buf += csize;
+		wsize += csize;
+		block += 1;
+	}
+
+	i_size_write(ea_inode, wsize);
+	ext4_update_i_disksize(ea_inode, wsize);
+
+	ext4_mark_inode_dirty(handle, ea_inode);
+
+out:
+	brelse(bh);
+
+	return ret;
+}
+
+/*
+ * Create an inode to store the value of a large EA.
+ */
+static struct inode *
+ext4_xattr_inode_create(handle_t *handle, struct inode *inode)
+{
+	struct inode *ea_inode = NULL;
+
+	/*
+	 * Let the next inode be the goal, so we try and allocate the EA inode
+	 * in the same group, or nearby one.
+	 */
+	ea_inode = ext4_new_inode(handle, inode->i_sb->s_root->d_inode,
+				  S_IFREG|0600, inode->i_ino + 1);
+
+	if (!IS_ERR(ea_inode)) {
+		ea_inode->i_op = &ext4_file_inode_operations;
+		ea_inode->i_fop = &ext4_file_operations;
+		ext4_set_aops(inode);
+		ea_inode->i_generation = inode->i_generation;
+		EXT4_I(ea_inode)->i_flags |= EXT4_EA_INODE_FL;
+
+		/*
+		 * A back-pointer from EA inode to parent inode will be useful
+		 * for e2fsck.
+		 */
+		ea_inode->i_xattr_inode_parent = inode->i_ino;
+	}
+
+	return ea_inode;
+}
+
+/*
+ * Unlink the inode storing the value of the EA.
+ */
+static int
+ext4_xattr_inode_unlink(struct inode *inode, int ea_ino)
+{
+	struct inode *ea_inode = NULL;
+	int err;
+
+	ea_inode = ext4_xattr_inode_iget(inode, ea_ino, &err);
+	if (err)
+		return err;
+
+	ea_inode->i_nlink = 0;
+	iput(ea_inode);
+
+	return 0;
+}
+
+/*
+ * Add value of the EA in an inode.
+ */
+static int
+ext4_xattr_inode_set(handle_t *handle, struct inode *inode, int *ea_ino,
+		     const void *value, size_t value_len)
+{
+	struct inode *ea_inode = NULL;
+	int err;
+
+	/* Create an inode for the EA value */
+	ea_inode = ext4_xattr_inode_create(handle, inode);
+	if (IS_ERR(ea_inode))
+		return -1;
+
+	err = ext4_xattr_inode_write(handle, ea_inode, value, value_len);
+	if (err)
+		ea_inode->i_nlink = 0;
+	else
+		*ea_ino = ea_inode->i_ino;
+
+	iput(ea_inode);
+
+	return err;
+}
+
 struct ext4_xattr_info {
 	int name_index;
 	const char *name;
@@ -536,15 +796,23 @@  struct ext4_xattr_search {
 };
 
 static int
-ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s)
+ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s,
+		     handle_t *handle, struct inode *inode)
 {
 	struct ext4_xattr_entry *last;
 	size_t free, min_offs = s->end - s->base, name_len = strlen(i->name);
+	int in_inode = 0;
+
+	if ((EXT4_SB(inode->i_sb)->s_es->s_feature_incompat &
+	     EXT4_FEATURE_INCOMPAT_EA_INODE) &&
+	    (EXT4_XATTR_SIZE(i->value_len) >
+	     EXT4_XATTR_MIN_LARGE_EA_SIZE(inode->i_sb->s_blocksize)))
+		in_inode++;
 
 	/* Compute min_offs and last. */
 	last = s->first;
 	for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
-		if (!last->e_value_block && last->e_value_size) {
+		if (!last->e_value_inum && last->e_value_size) {
 			size_t offs = le16_to_cpu(last->e_value_offs);
 			if (offs < min_offs)
 				min_offs = offs;
@@ -552,16 +820,21 @@  ext4_xattr_set_entry(struct ext4_xattr_i
 	}
 	free = min_offs - ((void *)last - s->base) - sizeof(__u32);
 	if (!s->not_found) {
-		if (!s->here->e_value_block && s->here->e_value_size) {
+		if (in_inode == 0 && !s->here->e_value_inum &&
+		    s->here->e_value_size) {
 			size_t size = le32_to_cpu(s->here->e_value_size);
 			free += EXT4_XATTR_SIZE(size);
 		}
 		free += EXT4_XATTR_LEN(name_len);
 	}
 	if (i->value) {
-		if (free < EXT4_XATTR_SIZE(i->value_len) ||
-		    free < EXT4_XATTR_LEN(name_len) +
-			   EXT4_XATTR_SIZE(i->value_len))
+		size_t value_len = EXT4_XATTR_SIZE(i->value_len);
+
+		if (in_inode)
+			value_len = 0;
+
+		if (free < value_len ||
+		    free < EXT4_XATTR_LEN(name_len) + value_len)
 			return -ENOSPC;
 	}
 
@@ -575,7 +848,8 @@  ext4_xattr_set_entry(struct ext4_xattr_i
 		s->here->e_name_len = name_len;
 		memcpy(s->here->e_name, i->name, name_len);
 	} else {
-		if (!s->here->e_value_block && s->here->e_value_size) {
+		if (s->here->e_value_offs && !s->here->e_value_inum &&
+		    s->here->e_value_size) {
 			void *first_val = s->base + min_offs;
 			size_t offs = le16_to_cpu(s->here->e_value_offs);
 			void *val = s->base + offs;
@@ -604,13 +878,16 @@  ext4_xattr_set_entry(struct ext4_xattr_i
 			last = s->first;
 			while (!IS_LAST_ENTRY(last)) {
 				size_t o = le16_to_cpu(last->e_value_offs);
-				if (!last->e_value_block &&
-				    last->e_value_size && o < offs)
+				if (last->e_value_size && o < offs)
 					last->e_value_offs =
 						cpu_to_le16(o + size);
 				last = EXT4_XATTR_NEXT(last);
 			}
 		}
+		if (s->here->e_value_inum) {
+			ext4_xattr_inode_unlink(inode, s->here->e_value_inum);
+			s->here->e_value_inum = 0;
+		}
 		if (!i->value) {
 			/* Remove the old name. */
 			size_t size = EXT4_XATTR_LEN(name_len);
@@ -624,13 +901,24 @@  ext4_xattr_set_entry(struct ext4_xattr_i
 	if (i->value) {
 		/* Insert the new value. */
 		s->here->e_value_size = cpu_to_le32(i->value_len);
-		if (i->value_len) {
-			size_t size = EXT4_XATTR_SIZE(i->value_len);
-			void *val = s->base + min_offs - size;
-			s->here->e_value_offs = cpu_to_le16(min_offs - size);
-			memset(val + size - EXT4_XATTR_PAD, 0,
-			       EXT4_XATTR_PAD); /* Clear the pad bytes. */
-			memcpy(val, i->value, i->value_len);
+		if (in_inode) {
+			int ea_ino = s->here->e_value_inum;
+			ext4_xattr_inode_set(handle, inode, &ea_ino, i->value,
+					     i->value_len);
+			s->here->e_value_inum = ea_ino;
+			s->here->e_value_offs = 0;
+		} else {
+			if (i->value_len) {
+				size_t size = EXT4_XATTR_SIZE(i->value_len);
+				void *val = s->base + min_offs - size;
+				s->here->e_value_offs = cpu_to_le16(min_offs -
+								    size);
+				s->here->e_value_inum = 0;
+				/* Clear the pad bytes */
+				memset(val + size - EXT4_XATTR_PAD, 0,
+				       EXT4_XATTR_PAD);
+				memcpy(val, i->value, i->value_len);
+			}
 		}
 	}
 	return 0;
@@ -673,7 +961,7 @@  ext4_xattr_block_find(struct inode *inod
 		bs->s.end = bs->bh->b_data + bs->bh->b_size;
 		bs->s.here = bs->s.first;
 		error = ext4_xattr_find_entry(&bs->s.here, i->name_index,
-					      i->name, bs->bh->b_size, 1);
+					     i->name, bs->bh->b_size, 1, inode);
 		if (error && error != -ENODATA)
 			goto cleanup;
 		bs->s.not_found = error;
@@ -697,8 +985,6 @@  ext4_xattr_block_set(handle_t *handle, s
 
 #define header(x) ((struct ext4_xattr_header *)(x))
 
-	if (i->value && i->value_len > sb->s_blocksize)
-		return -ENOSPC;
 	if (s->base) {
 		ce = mb_cache_entry_get(ext4_xattr_cache, bs->bh->b_bdev,
 					bs->bh->b_blocknr);
@@ -713,7 +999,7 @@  ext4_xattr_block_set(handle_t *handle, s
 				ce = NULL;
 			}
 			ea_bdebug(bs->bh, "modifying in-place");
-			error = ext4_xattr_set_entry(i, s);
+			error = ext4_xattr_set_entry(i, s, handle, inode);
 			if (!error) {
 				if (!IS_LAST_ENTRY(s->first))
 					ext4_xattr_rehash(header(s->base),
@@ -764,7 +1050,7 @@  ext4_xattr_block_set(handle_t *handle, s
 		s->end = s->base + sb->s_blocksize;
 	}
 
-	error = ext4_xattr_set_entry(i, s);
+	error = ext4_xattr_set_entry(i, s, handle, inode);
 	if (error == -EIO)
 		goto bad_block;
 	if (error)
@@ -896,7 +1182,7 @@  ext4_xattr_ibody_find(struct inode *inod
 		/* Find the named attribute. */
 		error = ext4_xattr_find_entry(&is->s.here, i->name_index,
 					      i->name, is->s.end -
-					      (void *)is->s.base, 0);
+					      (void *)is->s.base, 0, inode);
 		if (error && error != -ENODATA)
 			return error;
 		is->s.not_found = error;
@@ -915,7 +1201,7 @@  ext4_xattr_ibody_set(handle_t *handle, s
 
 	if (EXT4_I(inode)->i_extra_isize == 0)
 		return -ENOSPC;
-	error = ext4_xattr_set_entry(i, s);
+	error = ext4_xattr_set_entry(i, s, handle, inode);
 	if (error)
 		return error;
 	header = IHDR(inode, ext4_raw_inode(&is->iloc));
@@ -1065,10 +1351,26 @@  ext4_xattr_set(struct inode *inode, int 
 	       const void *value, size_t value_len, int flags)
 {
 	handle_t *handle;
+	struct super_block *sb = inode->i_sb;
+	int buffer_credits;
 	int error, retries = 0;
 
+	buffer_credits = EXT4_DATA_TRANS_BLOCKS(sb);
+	if ((value_len >= EXT4_XATTR_MIN_LARGE_EA_SIZE(sb->s_blocksize)) &&
+	    (EXT4_SB(sb)->s_es->s_feature_incompat &
+	     EXT4_FEATURE_INCOMPAT_EA_INODE)) {
+		int nrblocks = (value_len + sb->s_blocksize - 1) /
+								sb->s_blocksize;
+
+		/* For new inode */
+		buffer_credits += EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + 3;
+
+		/* For data blocks of EA inode */
+		buffer_credits += ext4_meta_trans_blocks(inode, nrblocks, 0);
+	}
+
 retry:
-	handle = ext4_journal_start(inode, EXT4_DATA_TRANS_BLOCKS(inode->i_sb));
+	handle = ext4_journal_start(inode, buffer_credits);
 	if (IS_ERR(handle)) {
 		error = PTR_ERR(handle);
 	} else {
@@ -1078,7 +1380,7 @@  retry:
 					      value, value_len, flags);
 		error2 = ext4_journal_stop(handle);
 		if (error == -ENOSPC &&
-		    ext4_should_retry_alloc(inode->i_sb, &retries))
+		    ext4_should_retry_alloc(sb, &retries))
 			goto retry;
 		if (error == 0)
 			error = error2;
@@ -1100,7 +1402,7 @@  static void ext4_xattr_shift_entries(str
 
 	/* Adjust the value offsets of the entries */
 	for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
-		if (!last->e_value_block && last->e_value_size) {
+		if (!last->e_value_inum && last->e_value_size) {
 			new_offs = le16_to_cpu(last->e_value_offs) +
 							value_offs_shift;
 			BUG_ON(new_offs + le32_to_cpu(last->e_value_size)
@@ -1337,7 +1639,8 @@  cleanup:
 /*
  * ext4_xattr_delete_inode()
  *
- * Free extended attribute resources associated with this inode. This
+ * Free extended attribute resources associated with this inode. Traverse
+ * all the entries and unlink any EA-inodes associated with this inode. This
  * is called immediately before an inode is freed. We have exclusive
  * access to the inode.
  */
@@ -1345,7 +1648,29 @@  void
 ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
 {
 	struct buffer_head *bh = NULL;
+	struct ext4_xattr_ibody_header *header;
+	struct ext4_inode *raw_inode;
+	struct ext4_iloc iloc;
+	struct ext4_xattr_entry *entry;
+	int error;
+
+	if (!(EXT4_I(inode)->i_state & EXT4_STATE_XATTR))
+		goto delete_external_ea;
+
+	error = ext4_get_inode_loc(inode, &iloc);
+	if (error)
+		goto cleanup;
+	raw_inode = ext4_raw_inode(&iloc);
+	header = IHDR(inode, raw_inode);
+	entry = IFIRST(header);
+	for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
+		if (entry->e_value_inum) {
+			ext4_xattr_inode_unlink(inode, entry->e_value_inum);
+			entry->e_value_inum = 0;
+		}
+	}
 
+delete_external_ea:
 	if (!EXT4_I(inode)->i_file_acl)
 		goto cleanup;
 	bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl);
@@ -1362,6 +1687,15 @@  ext4_xattr_delete_inode(handle_t *handle
 			EXT4_I(inode)->i_file_acl);
 		goto cleanup;
 	}
+
+	entry = BFIRST(bh);
+	for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
+		if (entry->e_value_inum) {
+			ext4_xattr_inode_unlink(inode, entry->e_value_inum);
+			entry->e_value_inum = 0;
+		}
+	}
+
 	ext4_xattr_release_block(handle, inode, bh);
 	EXT4_I(inode)->i_file_acl = 0;
 
@@ -1436,10 +1770,9 @@  ext4_xattr_cmp(struct ext4_xattr_header 
 		    entry1->e_name_index != entry2->e_name_index ||
 		    entry1->e_name_len != entry2->e_name_len ||
 		    entry1->e_value_size != entry2->e_value_size ||
+		    entry1->e_value_inum != entry2->e_value_inum ||
 		    memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len))
 			return 1;
-		if (entry1->e_value_block != 0 || entry2->e_value_block != 0)
-			return -EIO;
 		if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs),
 			   (char *)header2 + le16_to_cpu(entry2->e_value_offs),
 			   le32_to_cpu(entry1->e_value_size)))
@@ -1524,7 +1857,7 @@  static inline void ext4_xattr_hash_entry
 		       *name++;
 	}
 
-	if (entry->e_value_block == 0 && entry->e_value_size != 0) {
+	if (entry->e_value_inum == 0 && entry->e_value_size != 0) {
 		__le32 *value = (__le32 *)((char *)header +
 			le16_to_cpu(entry->e_value_offs));
 		for (n = (le32_to_cpu(entry->e_value_size) +
Index: linux-2.6.27/fs/ext4/xattr.h
===================================================================
--- linux-2.6.27.orig/fs/ext4/xattr.h
+++ linux-2.6.27/fs/ext4/xattr.h
@@ -38,7 +38,7 @@  struct ext4_xattr_entry {
 	__u8	e_name_len;	/* length of name */
 	__u8	e_name_index;	/* attribute name index */
 	__le16	e_value_offs;	/* offset in disk block of value */
-	__le32	e_value_block;	/* disk block attribute is stored on (n/i) */
+	__le32	e_value_inum;	/* inode in which the value is stored */
 	__le32	e_value_size;	/* size of attribute value */
 	__le32	e_hash;		/* hash value of name and value */
 	char	e_name[0];	/* attribute name */
@@ -63,6 +63,15 @@  struct ext4_xattr_entry {
 		EXT4_I(inode)->i_extra_isize))
 #define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1))
 
+#define i_xattr_inode_parent i_mtime.tv_sec
+
+/*
+ * The minimum size of EA value when you start storing it in an external inode
+ * should be half the blocksize.
+ */
+#define EXT4_XATTR_MIN_LARGE_EA_SIZE(b)	((b) >> 1)
+#define EXT4_XATTR_MAX_LARGE_EA_SIZE	(1024 * 1024)
+
 # ifdef CONFIG_EXT4_FS_XATTR
 
 extern struct xattr_handler ext4_xattr_user_handler;
Index: linux-2.6.27/fs/ext4/ext4.h
===================================================================
--- linux-2.6.27.orig/fs/ext4/ext4.h
+++ linux-2.6.27/fs/ext4/ext4.h
@@ -242,9 +242,10 @@  struct flex_groups {
 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
 #define EXT4_EXT_MIGRATE		0x00100000 /* Inode is migrating */
+#define EXT4_EA_INODE_FL		0x00200000 /* Inode used for large EA */
 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
 
-#define EXT4_FL_USER_VISIBLE		0x000BDFFF /* User visible flags */
+#define EXT4_FL_USER_VISIBLE		0x002BDFFF /* User visible flags */
 #define EXT4_FL_USER_MODIFIABLE		0x000B80FF /* User modifiable flags */
 
 /*
@@ -768,6 +769,7 @@  static inline int ext4_valid_inum(struct
 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
+#define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400
 
 #define EXT4_FEATURE_COMPAT_SUPP	EXT2_FEATURE_COMPAT_EXT_ATTR
 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
@@ -775,7 +777,8 @@  static inline int ext4_valid_inum(struct
 					 EXT4_FEATURE_INCOMPAT_META_BG| \
 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
 					 EXT4_FEATURE_INCOMPAT_64BIT| \
-					 EXT4_FEATURE_INCOMPAT_FLEX_BG)
+					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
+					 EXT4_FEATURE_INCOMPAT_EA_INODE)
 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \