Viewing: ext4-data-in-dirent.patch

commit 2db3b2b33ee796f4ea61316773452d936303ad27
Author:     Pravin Shelar <Pravin.Shelar@sun.com>
AuthorDate: Sun Oct 4 18:13:14 2009 +0000
Subject: ext4: add ext4-data-in-dirent patch

Allows ext4 to store extra data records inside the ext4_dirent
along with the regular directory entry (type, length, filename).
Data is stored in ext4 dirent after filename, with a bit flag in
de->file_type to indicate if any record after de->name is used.

Each in-use record is variable length and must store a 1-byte
length (including the length byte itself) at the start so that it
can be skipped if the record type is unknown/uneeded.  The record
starts after a NUL byte terminator for the filename.  This extra
space is accounted in de->rec_len but not de->name_len.

Flag EXT4_DIRENT_LUFID is used to store one or more 128-bit file
identifiers (FIDs, len=1 + 16 * N bytes).
Make use of dentry->d_fsdata to pass LUFID to ext4, so no changes
in ext4_add_entry() interface are required.

Bugzilla-ID: b=17670
Signed-off-by: Pravin Shelar <Pravin.Shelar@sun.com>
Reviewed-by: Huang Hua <h.huang@sun.com>
Signed-off-by: Andreas Dilger <andreas.dilger@sun.com>
---
 fs/ext4/dir.c         |   9 +-
 fs/ext4/ext4.h        | 106 ++++++++++++++-
 fs/ext4/fast_commit.c |   2 +-
 fs/ext4/inline.c      |   8 +-
 fs/ext4/namei.c       | 295 ++++++++++++++++++++++++++++++++++++------
 fs/ext4/super.c       |   4 +-
 6 files changed, 368 insertions(+), 56 deletions(-)

diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
index 74b172a4..c6afabcb 100644
--- a/fs/ext4/dir.c
+++ b/fs/ext4/dir.c
@@ -466,12 +466,17 @@ int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
 	struct fname *fname, *new_fn;
 	struct dir_private_info *info;
 	int len;
+	int extra_data = 0;
 
 	info = dir_file->private_data;
 	p = &info->root.rb_node;
 
 	/* Create and allocate the fname structure */
-	len = sizeof(struct fname) + ent_name->len + 1;
+	if (dirent->file_type & EXT4_DIRENT_LUFID)
+		extra_data = ext4_get_dirent_data_len(dirent);
+
+	len = sizeof(struct fname) + ent_name->len + extra_data + 1;
+
 	new_fn = kzalloc(len, GFP_KERNEL);
 	if (!new_fn)
 		return -ENOMEM;
@@ -480,7 +485,7 @@ int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
 	new_fn->inode = le32_to_cpu(dirent->inode);
 	new_fn->name_len = ent_name->len;
 	new_fn->file_type = dirent->file_type;
-	memcpy(new_fn->name, ent_name->name, ent_name->len);
+	memcpy(new_fn->name, ent_name->name, ent_name->len + extra_data);
 
 	while (*p) {
 		parent = *p;
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 645015d5..3b5b6df9 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1168,6 +1168,7 @@ struct ext4_inode_info {
 	__u32 i_csum_seed;
 
 	kprojid_t i_projid;
+	void *i_dirdata;
 };
 
 /*
@@ -1189,6 +1190,7 @@ struct ext4_inode_info {
  * Mount flags set via mount options or defaults
  */
 #define EXT4_MOUNT_NO_MBCACHE		0x00001 /* Do not use mbcache */
+#define EXT4_MOUNT_DIRDATA		0x00002	/* Data in directory entries */
 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
@@ -2140,6 +2142,7 @@ EXT4_FEATURE_INCOMPAT_FUNCS(casefold,		CASEFOLD)
 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
 					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
 					 EXT4_FEATURE_INCOMPAT_MMP | \
+					 EXT4_FEATURE_INCOMPAT_DIRDATA| \
 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
 					 EXT4_FEATURE_INCOMPAT_CASEFOLD | \
@@ -2349,6 +2352,42 @@ struct ext4_dir_entry_tail {
 #define EXT4_FT_SYMLINK		7
 
 #define EXT4_FT_MAX		8
+#define EXT4_FT_MASK		0xf
+
+#if EXT4_FT_MAX > EXT4_FT_MASK
+#error "conflicting EXT4_FT_MAX and EXT4_FT_MASK"
+#endif
+
+/*
+ * d_type has 4 unused bits, so it can hold four types data. these different
+ * type of data (e.g. lustre data, high 32 bits of 64-bit inode number) can be
+ * stored, in flag order, after file-name in ext4 dirent.
+*/
+/*
+ * this flag is added to d_type if ext4 dirent has extra data after
+ * filename. this data length is variable and length is stored in first byte
+ * of data. data start after filename NUL byte.
+ * This is used by Lustre FS.
+  */
+#define EXT4_DIRENT_LUFID		0x10
+
+#define EXT4_LUFID_MAGIC    0xAD200907UL
+struct ext4_dentry_param {
+	__u32  edp_magic;	/* EXT4_LUFID_MAGIC */
+	char   edp_len;		/* size of edp_data in bytes */
+	char   edp_data[0];	/* packed array of data */
+} __packed;
+
+static inline unsigned char *ext4_dentry_get_data(struct super_block *sb,
+						  struct ext4_dentry_param *p)
+{
+	if (!ext4_has_feature_dirdata(sb))
+		return NULL;
+	if (p && p->edp_magic == EXT4_LUFID_MAGIC)
+		return &p->edp_len;
+	else
+		return NULL;
+}
 
 #define EXT4_FT_DIR_CSUM	0xDE
 
@@ -2360,6 +2399,17 @@ struct ext4_dir_entry_tail {
 #define EXT4_DIR_PAD			4
 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
 #define EXT4_MAX_REC_LEN		((1<<16)-1)
+#define EXT4_DIR_REC_LEN_(name_len, i_dir) \
+	ext4_dir_rec_len((name_len), (i_dir))
+#define EXT4_DIR_ENTRY_LEN_(de, i_dir) \
+	(EXT4_DIR_REC_LEN_((de)->name_len + ext4_get_dirent_data_len(de), \
+		(i_dir)))
+/* ldiskfs */
+#define EXT4_DIR_REC_LEN(name_len, i_dir)	EXT4_DIR_REC_LEN_((name_len), (i_dir))
+#define EXT4_DIR_ENTRY_LEN(de, i_dir)		EXT4_DIR_ENTRY_LEN_((de), (i_dir))
+/* lustre osd_handler compat -- ifdef LDISKFS_DIR_REC_LEN_WITH_DIR */
+#define EXT4_DIR_REC_LEN_WITH_DIR		1
+#define __EXT4_DIR_REC_LEN(name_len)		EXT4_DIR_REC_LEN_((name_len), NULL)
 
 /*
  * The rec_len is dependent on the type of directory. Directories that are
@@ -2367,10 +2417,10 @@ struct ext4_dir_entry_tail {
  * ext4_extended_dir_entry_2. For all entries related to '.' or '..' you should
  * pass NULL for dir, as those entries do not use the extra fields.
  */
-static inline unsigned int ext4_dir_rec_len(__u8 name_len,
+static inline unsigned int ext4_dir_rec_len(__u32 name_len,
 						const struct inode *dir)
 {
-	int rec_len = (name_len + 8 + EXT4_DIR_ROUND);
+	__u32 rec_len = (name_len + 8 + EXT4_DIR_ROUND);
 
 	if (dir && ext4_hash_in_dirent(dir))
 		rec_len += sizeof(struct ext4_dir_entry_hash);
@@ -2848,11 +2898,13 @@ extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
 			     struct buffer_head *bh,
 			     void *buf, int buf_size,
 			     struct ext4_filename *fname,
-			     struct ext4_dir_entry_2 **dest_de);
+			     struct ext4_dir_entry_2 **dest_de,
+			     int dlen);
 void ext4_insert_dentry(struct inode *dir, struct inode *inode,
 			struct ext4_dir_entry_2 *de,
 			int buf_size,
-			struct ext4_filename *fname);
+			struct ext4_filename *fname,
+			void *data);
 static inline void ext4_update_dx_flag(struct inode *inode)
 {
 	if (!ext4_has_feature_dir_index(inode->i_sb) &&
@@ -2868,10 +2920,17 @@ static const unsigned char ext4_filetype_table[] = {
 
 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
 {
-	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
+	int fl_index = filetype & EXT4_FT_MASK;
+
+	if (!ext4_has_feature_filetype(sb) || fl_index >= EXT4_FT_MAX)
 		return DT_UNKNOWN;
 
-	return ext4_filetype_table[filetype];
+	if (!test_opt(sb, DIRDATA))
+		return ext4_filetype_table[fl_index];
+
+	return (ext4_filetype_table[fl_index]) |
+		(filetype & EXT4_DIRENT_LUFID);
+
 }
 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
 			     void *buf, int buf_size);
@@ -3075,7 +3134,8 @@ extern int ext4_ind_migrate(struct inode *inode);
 
 /* namei.c */
 extern int ext4_init_new_dir(handle_t *handle, struct inode *dir,
-			     struct inode *inode);
+			     struct inode *inode,
+			     const void *data1, const void *data2);
 extern int ext4_dirblock_csum_verify(struct inode *inode,
 				     struct buffer_head *bh);
 extern int ext4_orphan_add(handle_t *, struct inode *);
@@ -3086,6 +3146,8 @@ extern struct inode *ext4_create_inode(handle_t *handle,
 extern int ext4_delete_entry(handle_t *handle, struct inode * dir,
 			     struct ext4_dir_entry_2 *de_del,
 			     struct buffer_head *bh);
+extern int ext4_add_dot_dotdot(handle_t *handle, struct inode *dir,
+			       struct inode *inode, const void *, const void *);
 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
 				__u32 start_minor_hash, __u32 *next_hash);
 extern int ext4_search_dir(struct buffer_head *bh,
@@ -3892,6 +3954,36 @@ static inline int ext4_buffer_uptodate(struct buffer_head *bh)
 	return buffer_uptodate(bh);
 }
 
+/*
+ * Compute the total directory entry data length.
+ * This includes the filename and an implicit NUL terminator (always present),
+ * and optional extensions.  Each extension has a bit set in the high 4 bits of
+ * de->file_type, and the extension length is the first byte in each entry.
+ */
+static inline int ext4_get_dirent_data_len(struct ext4_dir_entry_2 *de)
+{
+	char *len = de->name + de->name_len + 1 /* NUL terminator */;
+	int dlen = 0;
+	__u8 extra_data_flags = (de->file_type & ~EXT4_FT_MASK) >> 4;
+	struct ext4_dir_entry_tail *t = (struct ext4_dir_entry_tail *)de;
+
+	if (!t->det_reserved_zero1 &&
+	    le16_to_cpu(t->det_rec_len) ==
+		sizeof(struct ext4_dir_entry_tail) &&
+	    !t->det_reserved_zero2 &&
+	    t->det_reserved_ft == EXT4_FT_DIR_CSUM)
+		return 0;
+
+	while (extra_data_flags) {
+		if (extra_data_flags & 1) {
+			dlen += *len + (dlen == 0);
+			len += *len;
+		}
+		extra_data_flags >>= 1;
+	}
+	return dlen;
+}
+
 #endif	/* __KERNEL__ */
 
 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c
index 6d9eb627..cf62b91e 100644
--- a/fs/ext4/fast_commit.c
+++ b/fs/ext4/fast_commit.c
@@ -1610,7 +1610,7 @@ static int ext4_fc_replay_create(struct super_block *sb,
 			jbd_debug(1, "Dir %d not found.", darg.ino);
 			goto out;
 		}
-		ret = ext4_init_new_dir(NULL, dir, inode);
+		ret = ext4_init_new_dir(NULL, dir, inode, NULL, NULL);
 		iput(dir);
 		if (ret) {
 			ret = 0;
diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index a605204d..43cc7453 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -1031,7 +1031,7 @@ static int ext4_add_dirent_to_inline(handle_t *handle,
 	struct ext4_dir_entry_2 *de;
 
 	err = ext4_find_dest_de(dir, inode, iloc->bh, inline_start,
-				inline_size, fname, &de);
+				inline_size, fname, &de, 0);
 	if (err)
 		return err;
 
@@ -1040,7 +1040,7 @@ static int ext4_add_dirent_to_inline(handle_t *handle,
 					    EXT4_JTR_NONE);
 	if (err)
 		return err;
-	ext4_insert_dentry(dir, inode, de, inline_size, fname);
+	ext4_insert_dentry(dir, inode, de, inline_size, fname, NULL);
 
 	ext4_show_inline_dir(dir, iloc->bh, inline_start, inline_size);
 
@@ -1399,7 +1399,7 @@ int ext4_inlinedir_to_tree(struct file *dir_file,
 			fake.name_len = 1;
 			strcpy(fake.name, ".");
 			fake.rec_len = ext4_rec_len_to_disk(
-					  ext4_dir_rec_len(fake.name_len, NULL),
+					  EXT4_DIR_ENTRY_LEN(&fake, NULL),
 					  inline_size);
 			ext4_set_de_type(inode->i_sb, &fake, S_IFDIR);
 			de = &fake;
@@ -1409,7 +1409,7 @@ int ext4_inlinedir_to_tree(struct file *dir_file,
 			fake.name_len = 2;
 			strcpy(fake.name, "..");
 			fake.rec_len = ext4_rec_len_to_disk(
-					  ext4_dir_rec_len(fake.name_len, NULL),
+					  EXT4_DIR_ENTRY_LEN(&fake, NULL),
 					  inline_size);
 			ext4_set_de_type(inode->i_sb, &fake, S_IFDIR);
 			de = &fake;
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index a408e369..afac85df 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -290,7 +290,8 @@ static unsigned dx_get_count(struct dx_entry *entries);
 static unsigned dx_get_limit(struct dx_entry *entries);
 static void dx_set_count(struct dx_entry *entries, unsigned value);
 static void dx_set_limit(struct dx_entry *entries, unsigned value);
-static unsigned dx_root_limit(struct inode *dir, unsigned infosize);
+static inline unsigned dx_root_limit(struct inode *dir,
+		struct ext4_dir_entry_2 *dot_de, unsigned infosize);
 static unsigned dx_node_limit(struct inode *dir);
 static struct dx_frame *dx_probe(struct ext4_filename *fname,
 				 struct inode *dir,
@@ -436,22 +437,23 @@ static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
 {
 	struct ext4_dir_entry *dp;
 	struct dx_root_info *root;
-	int count_offset;
+	int count_offset, dot_rec_len, dotdot_rec_len;
 
 	if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
 		count_offset = 8;
-	else if (le16_to_cpu(dirent->rec_len) == 12) {
-		dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
+	else {
+		dot_rec_len = le16_to_cpu(dirent->rec_len);
+		dp = (struct ext4_dir_entry *)(((void *)dirent) + dot_rec_len);
 		if (le16_to_cpu(dp->rec_len) !=
-		    EXT4_BLOCK_SIZE(inode->i_sb) - 12)
+		    EXT4_BLOCK_SIZE(inode->i_sb) - dot_rec_len)
 			return NULL;
-		root = (struct dx_root_info *)(((void *)dp + 12));
+		dotdot_rec_len = EXT4_DIR_ENTRY_LEN((struct ext4_dir_entry_2 *)dp, NULL);
+		root = (struct dx_root_info *)(((void *)dp + dotdot_rec_len));
 		if (root->reserved_zero ||
 		    root->info_length != sizeof(struct dx_root_info))
 			return NULL;
-		count_offset = 32;
-	} else
-		return NULL;
+		count_offset = 8 + dot_rec_len + dotdot_rec_len;
+	}
 
 	if (offset)
 		*offset = count_offset;
@@ -556,11 +558,12 @@ ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)
  */
 struct dx_root_info *dx_get_dx_info(struct ext4_dir_entry_2 *de)
 {
+	BUG_ON(de->name_len != 1);
 	/* get dotdot first */
-	de = (struct ext4_dir_entry_2 *)((char *)de + EXT4_DIR_REC_LEN(1));
+	de = (struct ext4_dir_entry_2 *)((char *)de + EXT4_DIR_ENTRY_LEN(de, NULL));
 
 	/* dx root info is after dotdot entry */
-	de = (struct ext4_dir_entry_2 *)((char *)de + EXT4_DIR_REC_LEN(2));
+	de = (struct ext4_dir_entry_2 *)((char *)de + EXT4_DIR_ENTRY_LEN(de, NULL));
 
 	return (struct dx_root_info *)de;
 }
@@ -605,11 +608,16 @@ static inline void dx_set_limit(struct dx_entry *entries, unsigned value)
 	((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
 }
 
-static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)
+static inline unsigned dx_root_limit(struct inode *dir,
+		struct ext4_dir_entry_2 *dot_de, unsigned infosize)
 {
-	unsigned int entry_space = dir->i_sb->s_blocksize -
-			ext4_dir_rec_len(1, NULL) -
-			ext4_dir_rec_len(2, NULL) - infosize;
+	struct ext4_dir_entry_2 *dotdot_de;
+	unsigned entry_space;
+
+	BUG_ON(dot_de->name_len != 1);
+	dotdot_de = ext4_next_entry(dot_de, dir->i_sb->s_blocksize);
+	entry_space = dir->i_sb->s_blocksize - EXT4_DIR_ENTRY_LEN(dot_de, NULL) -
+			 EXT4_DIR_ENTRY_LEN(dotdot_de, NULL) - infosize;
 
 	if (ext4_has_metadata_csum(dir->i_sb))
 		entry_space -= sizeof(struct dx_tail);
@@ -729,7 +737,7 @@ static struct stats dx_show_leaf(struct inode *dir,
 				       (unsigned) ((char *) de - base));
 #endif
 			}
-			space += ext4_dir_rec_len(de->name_len, dir);
+			space += EXT4_DIR_ENTRY_LEN(de, dir);
 			names++;
 		}
 		de = ext4_next_entry(de, size);
@@ -885,11 +893,14 @@ dx_probe(struct ext4_filename *fname, struct inode *dir,
 
 	entries = (struct dx_entry *)(((char *)info) + info->info_length);
 
-	if (dx_get_limit(entries) != dx_root_limit(dir,
-						   info->info_length)) {
+	if (dx_get_limit(entries) !=
+	    dx_root_limit(dir, (struct ext4_dir_entry_2 *)frame->bh->b_data,
+			  info->info_length)) {
 		ext4_warning_inode(dir, "dx entry: limit %u != root limit %u",
 				   dx_get_limit(entries),
-				   dx_root_limit(dir, info->info_length));
+				   dx_root_limit(dir,
+					  (struct ext4_dir_entry_2 *)frame->bh->b_data,
+					  info->info_length));
 		goto fail;
 	}
 
@@ -1945,7 +1956,7 @@ dx_move_dirents(struct inode *dir, char *from, char *to,
 	while (count--) {
 		struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)
 						(from + (map->offs<<2));
-		rec_len = ext4_dir_rec_len(de->name_len, dir);
+		rec_len = EXT4_DIR_ENTRY_LEN(de, dir);
 
 		memcpy (to, de, rec_len);
 		((struct ext4_dir_entry_2 *) to)->rec_len =
@@ -1978,7 +1989,7 @@ static struct ext4_dir_entry_2 *dx_pack_dirents(struct inode *dir, char *base,
 	while ((char*)de < base + blocksize) {
 		next = ext4_next_entry(de, blocksize);
 		if (de->inode && de->name_len) {
-			rec_len = ext4_dir_rec_len(de->name_len, dir);
+			rec_len = EXT4_DIR_ENTRY_LEN(de, dir);
 			if (de > to)
 				memmove(to, de, rec_len);
 			to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);
@@ -2121,10 +2132,11 @@ int ext4_find_dest_de(struct inode *dir, struct inode *inode,
 		      struct buffer_head *bh,
 		      void *buf, int buf_size,
 		      struct ext4_filename *fname,
-		      struct ext4_dir_entry_2 **dest_de)
+		      struct ext4_dir_entry_2 **dest_de,
+		      int dlen)
 {
 	struct ext4_dir_entry_2 *de;
-	unsigned short reclen = ext4_dir_rec_len(fname_len(fname), dir);
+	unsigned short reclen = ext4_dir_rec_len(fname_len(fname) + dlen, dir);
 	int nlen, rlen;
 	unsigned int offset = 0;
 	char *top;
@@ -2137,7 +2149,7 @@ int ext4_find_dest_de(struct inode *dir, struct inode *inode,
 			return -EFSCORRUPTED;
 		if (ext4_match(dir, fname, de))
 			return -EEXIST;
-		nlen = ext4_dir_rec_len(de->name_len, dir);
+		nlen = EXT4_DIR_ENTRY_LEN(de, dir);
 		rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
 		if ((de->inode ? rlen - nlen : rlen) >= reclen)
 			break;
@@ -2155,12 +2167,13 @@ void ext4_insert_dentry(struct inode *dir,
 			struct inode *inode,
 			struct ext4_dir_entry_2 *de,
 			int buf_size,
-			struct ext4_filename *fname)
+			struct ext4_filename *fname,
+			void *data)
 {
 
 	int nlen, rlen;
 
-	nlen = ext4_dir_rec_len(de->name_len, dir);
+	nlen = EXT4_DIR_ENTRY_LEN(de, dir);
 	rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
 	if (de->inode) {
 		struct ext4_dir_entry_2 *de1 =
@@ -2181,6 +2194,12 @@ void ext4_insert_dentry(struct inode *dir,
 		EXT4_DIRENT_HASHES(de)->minor_hash =
 						cpu_to_le32(hinfo->minor_hash);
 	}
+	if (data) {
+		de->name[fname_len(fname)] = 0;
+		memcpy(&de->name[fname_len(fname) + 1], data, *(char *)data);
+		de->file_type |= EXT4_DIRENT_LUFID;
+	}
+
 }
 
 /*
@@ -2198,14 +2217,19 @@ static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname,
 {
 	unsigned int	blocksize = dir->i_sb->s_blocksize;
 	int		csum_size = 0;
-	int		err, err2;
+	int		err, err2, dlen = 0;
+	unsigned char	*data;
 
+	data = ext4_dentry_get_data(inode->i_sb, (struct ext4_dentry_param *)
+						EXT4_I(inode)->i_dirdata);
 	if (ext4_has_metadata_csum(inode->i_sb))
 		csum_size = sizeof(struct ext4_dir_entry_tail);
 
 	if (!de) {
+		if (data)
+			dlen = (*data) + 1;
 		err = ext4_find_dest_de(dir, inode, bh, bh->b_data,
-					blocksize - csum_size, fname, &de);
+					blocksize - csum_size, fname, &de, dlen);
 		if (err)
 			return err;
 	}
@@ -2218,7 +2242,7 @@ static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname,
 	}
 
 	/* By now the buffer is marked for journaling */
-	ext4_insert_dentry(dir, inode, de, blocksize, fname);
+	ext4_insert_dentry(dir, inode, de, blocksize, fname, data);
 
 	/*
 	 * XXX shouldn't update any times until successful
@@ -2335,7 +2359,8 @@ static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname,
 	entries = (void *)dx_info + sizeof(*dx_info);
 	dx_set_block(entries, 1);
 	dx_set_count(entries, 1);
-	dx_set_limit(entries, dx_root_limit(dir, sizeof(*dx_info)));
+	dx_set_limit(entries, dx_root_limit(dir,
+					 dot_de, sizeof(*dx_info)));
 
 	/* Initialize as for dx_probe */
 	fname->hinfo.hash_version = dx_info->hash_version;
@@ -2386,7 +2411,106 @@ out_frames:
 	return retval;
 }
 
-/* update ".." entry */
+static int ext4_expand_dotdot(struct inode *dir,
+			      struct buffer_head *bh,
+			      int dlen)
+{
+	struct ext4_dir_entry_2 *dot_de;
+	struct ext4_dir_entry_2 *dotdot_de;
+	int len;
+	unsigned blocksize = dir->i_sb->s_blocksize;
+
+	dot_de = (struct ext4_dir_entry_2 *)bh->b_data;
+	dotdot_de = ext4_next_entry(dot_de, blocksize);
+
+	if (is_dx(dir)) {
+		struct dx_entry *entries;
+		struct dx_root_info *dx_info;
+		int limit, count;
+		int entry_space;
+
+		len = EXT4_DIR_REC_LEN(2 + dlen, NULL) -
+			EXT4_DIR_ENTRY_LEN(dotdot_de, NULL);
+
+		dx_info = dx_get_dx_info(dot_de);
+		entries = (struct dx_entry *)((char *)dx_info +
+							sizeof(*dx_info));
+		count = dx_get_count(entries);
+
+		/*
+		 * figure out new limit with dlen,
+		 * check if we have enough space
+		 */
+		entry_space = blocksize;
+		entry_space -= (char *)dotdot_de - (char *)dot_de +
+			       EXT4_DIR_REC_LEN(2 + dlen, NULL) +
+			       sizeof(*dx_info);
+		if (ext4_has_metadata_csum(dir->i_sb))
+			entry_space -= sizeof(struct dx_tail);
+		limit = entry_space / sizeof(struct dx_entry);
+		if (count > limit)
+			return -ENOSPC;
+
+		/* set the new limit, move dx_info and the entries */
+		dx_set_limit(entries, limit);
+		memmove((char *)dx_info + len, dx_info,
+			sizeof(*dx_info) + count * sizeof(struct dx_entry));
+	} else {
+		struct ext4_dir_entry_2 *next, *to, *prev, *de;
+		char *top = (char *)bh->b_data + blocksize;
+		int space = 0;
+		unsigned rec_len = 0;
+
+		len = EXT4_DIR_REC_LEN(2 + dlen, NULL) -
+			ext4_rec_len_from_disk(dotdot_de->rec_len, blocksize);
+
+		if (ext4_has_metadata_csum(dir->i_sb))
+			top -= sizeof(struct ext4_dir_entry_tail);
+
+		de = ext4_next_entry(dotdot_de, blocksize);
+		while ((char *)de < top) {
+			space += ext4_rec_len_from_disk(de->rec_len, blocksize) -
+					EXT4_DIR_ENTRY_LEN(de, dir);
+			de = ext4_next_entry(de, blocksize);
+		}
+
+		if (space < len)
+			return -ENOSPC;
+
+		/* pack all the entries after dotdot */
+		de = ext4_next_entry(dotdot_de, blocksize);
+		prev = to = de;
+		while ((char *)de < top) {
+			next = ext4_next_entry(de, blocksize);
+			if (de->inode && de->name_len) {
+				rec_len = EXT4_DIR_ENTRY_LEN(de, dir);
+				if (de > to)
+					memmove(to, de, rec_len);
+				to->rec_len = ext4_rec_len_to_disk(rec_len,
+								   blocksize);
+				prev = to;
+				to = (struct ext4_dir_entry_2 *)
+						(((char *)to) + rec_len);
+			}
+			de = next;
+		}
+		/* fix up rec_len for the last entry */
+		prev->rec_len = ext4_rec_len_to_disk(top - (char *)prev - len,
+						     blocksize);
+		/* move all the entries after dotdot to make space */
+		de = ext4_next_entry(dotdot_de, blocksize);
+		memmove((char *)de + len, de, (char *)prev - (char *)de +
+			EXT4_DIR_ENTRY_LEN(prev, dir));
+		/* fix the rec_len for dotdot */
+		dotdot_de->rec_len = ext4_rec_len_to_disk(
+					EXT4_DIR_REC_LEN(2 + dlen, NULL),
+					blocksize);
+	}
+
+	return 0;
+}
+
+/* update ".." entry, try to expand the entry if necessary */
 static int ext4_update_dotdot(handle_t *handle, struct dentry *dentry,
 			      struct inode *inode)
 {
@@ -2395,6 +2519,8 @@ static int ext4_update_dotdot(handle_t *handle, struct dentry *dentry,
 	struct ext4_dir_entry_2 *dot_de, *dotdot_de;
 	unsigned int offset;
 	int retval = 0;
+	int dlen = 0;
+	char *data;
 
 	if (IS_ERR(handle))
 		return PTR_ERR(handle);
@@ -2435,6 +2561,30 @@ static int ext4_update_dotdot(handle_t *handle, struct dentry *dentry,
 
 	dotdot_de->inode = cpu_to_le32(inode->i_ino);
 
+	data = ext4_dentry_get_data(dir->i_sb,
+			(struct ext4_dentry_param *)dentry->d_fsdata);
+	if (data != NULL) {
+		dlen = *data + 1;
+		if (is_dx(dir)) {
+			if (ext4_get_dirent_data_len(dotdot_de) < dlen) {
+				if (ext4_expand_dotdot(dir, bh, dlen) < 0)
+					dlen = 0;
+			}
+		} else {
+			if (ext4_rec_len_from_disk(dotdot_de->rec_len,
+						   dir->i_sb->s_blocksize) <
+			    EXT4_DIR_REC_LEN(2 + dlen, NULL)) {
+				if (ext4_expand_dotdot(dir, bh, dlen) < 0)
+					dlen = 0;
+			}
+		}
+	}
+	if (dlen) {
+		dotdot_de->name[2] = 0;
+		memcpy(&dotdot_de->name[2 + 1], data, *data);
+		dotdot_de->file_type |= LDISKFS_DIRENT_LUFID;
+	}
+
 	ext4_mark_inode_dirty(handle, dir);
 	BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
 	if (is_dx(dir)) {
@@ -2472,6 +2622,7 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
 	ext4_lblk_t block, blocks;
 	int	csum_size = 0;
 
+	EXT4_I(inode)->i_dirdata = dentry->d_fsdata;
 	if (ext4_has_metadata_csum(inode->i_sb))
 		csum_size = sizeof(struct ext4_dir_entry_tail);
 
@@ -3044,38 +3195,73 @@ err_unlock_inode:
 	return err;
 }
 
+struct tp_block {
+	struct inode *inode;
+	void *data1;
+	void *data2;
+};
+
 struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
 			  struct ext4_dir_entry_2 *de,
 			  int blocksize, int csum_size,
 			  unsigned int parent_ino, int dotdot_real_len)
 {
+	void *data1 = NULL, *data2 = NULL;
+	int dot_reclen = 0;
+
+	if (dotdot_real_len == 10) {
+		struct tp_block *tpb = (struct tp_block *)inode;
+		data1 = tpb->data1;
+		data2 = tpb->data2;
+		inode = tpb->inode;
+		dotdot_real_len = 0;
+	}
 	de->inode = cpu_to_le32(inode->i_ino);
 	de->name_len = 1;
-	de->rec_len = ext4_rec_len_to_disk(ext4_dir_rec_len(de->name_len, NULL),
-					   blocksize);
 	strcpy(de->name, ".");
 	ext4_set_de_type(inode->i_sb, de, S_IFDIR);
 
+	/* get packed fid data*/
+	data1 = ext4_dentry_get_data(inode->i_sb,
+				(struct ext4_dentry_param *) data1);
+	if (data1) {
+		de->name[1] = 0;
+		memcpy(&de->name[2], data1, *(char *) data1);
+		de->file_type |= EXT4_DIRENT_LUFID;
+	}
+	de->rec_len = cpu_to_le16(EXT4_DIR_ENTRY_LEN(de, NULL));
+
+	dot_reclen = cpu_to_le16(de->rec_len);
 	de = ext4_next_entry(de, blocksize);
 	de->inode = cpu_to_le32(parent_ino);
 	de->name_len = 2;
+
+	strcpy(de->name, "..");
+	ext4_set_de_type(inode->i_sb, de, S_IFDIR);
+	data2 = ext4_dentry_get_data(inode->i_sb,
+			(struct ext4_dentry_param *) data2);
+	if (data2) {
+		de->name[2] = 0;
+		memcpy(&de->name[3], data2, *(char *) data2);
+		de->file_type |= EXT4_DIRENT_LUFID;
+	}
+
 	if (!dotdot_real_len)
 		de->rec_len = ext4_rec_len_to_disk(blocksize -
-					(csum_size + ext4_dir_rec_len(1, NULL)),
-					blocksize);
+					(csum_size + dot_reclen), blocksize);
 	else
 		de->rec_len = ext4_rec_len_to_disk(
-					ext4_dir_rec_len(de->name_len, NULL),
+					EXT4_DIR_ENTRY_LEN(de, NULL),
 					blocksize);
-	strcpy(de->name, "..");
-	ext4_set_de_type(inode->i_sb, de, S_IFDIR);
 
 	return ext4_next_entry(de, blocksize);
 }
 
 int ext4_init_new_dir(handle_t *handle, struct inode *dir,
-			     struct inode *inode)
+			     struct inode *inode,
+			     const void *data1, const void *data2)
 {
+	struct tp_block param;
 	struct buffer_head *dir_block = NULL;
 	struct ext4_dir_entry_2 *de;
 	ext4_lblk_t block = 0;
@@ -3099,7 +3285,11 @@ int ext4_init_new_dir(handle_t *handle, struct inode *dir,
 	if (IS_ERR(dir_block))
 		return PTR_ERR(dir_block);
 	de = (struct ext4_dir_entry_2 *)dir_block->b_data;
-	ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0);
+	param.inode = inode;
+	param.data1 = (void *)data1;
+	param.data2 = (void *)data2;
+	ext4_init_dot_dotdot((struct inode *)(&param), de, blocksize,
+			     csum_size, dir->i_ino, 10);
 	set_nlink(inode, 2);
 	if (csum_size)
 		ext4_initialize_dirent_tail(dir_block, blocksize);
@@ -3114,6 +3304,29 @@ out:
 	return err;
 }
 
+/* Initialize @inode as a subdirectory of @dir, and add the
+ * "." and ".." entries into the first directory block. */
+int ext4_add_dot_dotdot(handle_t *handle, struct inode *dir,
+			struct inode *inode,
+			const void *data1, const void *data2)
+{
+	int rc;
+
+	if (IS_ERR(handle))
+		return PTR_ERR(handle);
+
+	if (IS_DIRSYNC(dir))
+		ext4_handle_sync(handle);
+
+	inode->i_op = &ext4_dir_inode_operations;
+	inode->i_fop = &ext4_dir_operations;
+	rc = ext4_init_new_dir(handle, dir, inode, data1, data2);
+	if (!rc)
+		rc = ext4_mark_inode_dirty(handle, inode);
+	return rc;
+}
+EXPORT_SYMBOL(ext4_add_dot_dotdot);
+
 static int ext4_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
 		      struct dentry *dentry, umode_t mode)
 {
@@ -3141,7 +3354,7 @@ retry:
 
 	inode->i_op = &ext4_dir_inode_operations;
 	inode->i_fop = &ext4_dir_operations;
-	err = ext4_init_new_dir(handle, dir, inode);
+	err = ext4_init_new_dir(handle, dir, inode, NULL, NULL);
 	if (err)
 		goto out_clear_inode;
 	err = ext4_mark_inode_dirty(handle, inode);
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 0af91da7..9b6ad3df 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1666,7 +1666,7 @@ enum {
 	Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
 	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
 	Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
-	Opt_inlinecrypt,
+	Opt_inlinecrypt, Opt_dirdata,
 	Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
 	Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
 	Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
@@ -1753,6 +1753,7 @@ static const match_table_t tokens = {
 	{Opt_nolazytime, "nolazytime"},
 	{Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
 	{Opt_nodelalloc, "nodelalloc"},
+	{Opt_dirdata, "dirdata"},
 	{Opt_removed, "mblk_io_submit"},
 	{Opt_removed, "nomblk_io_submit"},
 	{Opt_block_validity, "block_validity"},
@@ -1997,6 +1998,7 @@ static const struct mount_opts {
 	{Opt_usrjquota, 0, MOPT_Q | MOPT_STRING},
 	{Opt_grpjquota, 0, MOPT_Q | MOPT_STRING},
 	{Opt_offusrjquota, 0, MOPT_Q},
+	{Opt_dirdata, EXT4_MOUNT_DIRDATA, MOPT_SET},
 	{Opt_offgrpjquota, 0, MOPT_Q},
 	{Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
 	{Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
-- 
2.34.1