Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index ffa2575..a427d20 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -35,6 +35,7 @@
 #include <linux/buffer_head.h>
 #include <linux/bio.h>
 #include <linux/iversion.h>
+#include <linux/unicode.h>
 #include "ext4.h"
 #include "ext4_jbd2.h"
 
@@ -81,8 +82,18 @@
 static int ext4_dx_csum_verify(struct inode *inode,
 			       struct ext4_dir_entry *dirent);
 
+/*
+ * Hints to ext4_read_dirblock regarding whether we expect a directory
+ * block being read to be an index block, or a block containing
+ * directory entries (and if the latter, whether it was found via a
+ * logical block in an htree index block).  This is used to control
+ * what sort of sanity checkinig ext4_read_dirblock() will do on the
+ * directory block read from the storage device.  EITHER will means
+ * the caller doesn't know what kind of directory block will be read,
+ * so no specific verification will be done.
+ */
 typedef enum {
-	EITHER, INDEX, DIRENT
+	EITHER, INDEX, DIRENT, DIRENT_HTREE
 } dirblock_type_t;
 
 #define ext4_read_dirblock(inode, block, type) \
@@ -108,11 +119,14 @@
 
 		return bh;
 	}
-	if (!bh) {
+	if (!bh && (type == INDEX || type == DIRENT_HTREE)) {
 		ext4_error_inode(inode, func, line, block,
-				 "Directory hole found");
+				 "Directory hole found for htree %s block",
+				 (type == INDEX) ? "index" : "leaf");
 		return ERR_PTR(-EFSCORRUPTED);
 	}
+	if (!bh)
+		return NULL;
 	dirent = (struct ext4_dir_entry *) bh->b_data;
 	/* Determine whether or not we have an index block */
 	if (is_dx(inode)) {
@@ -149,7 +163,7 @@
 		}
 	}
 	if (!is_dx_block) {
-		if (ext4_dirent_csum_verify(inode, dirent))
+		if (ext4_dirblock_csum_verify(inode, bh))
 			set_buffer_verified(bh);
 		else {
 			ext4_error_inode(inode, func, line, block,
@@ -279,9 +293,11 @@
 			     struct inode *dir, struct inode *inode);
 
 /* checksumming functions */
-void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
-			    unsigned int blocksize)
+void ext4_initialize_dirent_tail(struct buffer_head *bh,
+				 unsigned int blocksize)
 {
+	struct ext4_dir_entry_tail *t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);
+
 	memset(t, 0, sizeof(struct ext4_dir_entry_tail));
 	t->det_rec_len = ext4_rec_len_to_disk(
 			sizeof(struct ext4_dir_entry_tail), blocksize);
@@ -290,17 +306,17 @@
 
 /* Walk through a dirent block to find a checksum "dirent" at the tail */
 static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
-						   struct ext4_dir_entry *de)
+						   struct buffer_head *bh)
 {
 	struct ext4_dir_entry_tail *t;
 
 #ifdef PARANOID
 	struct ext4_dir_entry *d, *top;
 
-	d = de;
-	top = (struct ext4_dir_entry *)(((void *)de) +
+	d = (struct ext4_dir_entry *)bh->b_data;
+	top = (struct ext4_dir_entry *)(bh->b_data +
 		(EXT4_BLOCK_SIZE(inode->i_sb) -
-		sizeof(struct ext4_dir_entry_tail)));
+		 sizeof(struct ext4_dir_entry_tail)));
 	while (d < top && d->rec_len)
 		d = (struct ext4_dir_entry *)(((void *)d) +
 		    le16_to_cpu(d->rec_len));
@@ -310,7 +326,7 @@
 
 	t = (struct ext4_dir_entry_tail *)d;
 #else
-	t = EXT4_DIRENT_TAIL(de, EXT4_BLOCK_SIZE(inode->i_sb));
+	t = EXT4_DIRENT_TAIL(bh->b_data, EXT4_BLOCK_SIZE(inode->i_sb));
 #endif
 
 	if (t->det_reserved_zero1 ||
@@ -322,8 +338,7 @@
 	return t;
 }
 
-static __le32 ext4_dirent_csum(struct inode *inode,
-			       struct ext4_dir_entry *dirent, int size)
+static __le32 ext4_dirblock_csum(struct inode *inode, void *dirent, int size)
 {
 	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 	struct ext4_inode_info *ei = EXT4_I(inode);
@@ -343,49 +358,49 @@
 		"No space for directory leaf checksum. Please run e2fsck -D.");
 }
 
-int ext4_dirent_csum_verify(struct inode *inode, struct ext4_dir_entry *dirent)
+int ext4_dirblock_csum_verify(struct inode *inode, struct buffer_head *bh)
 {
 	struct ext4_dir_entry_tail *t;
 
 	if (!ext4_has_metadata_csum(inode->i_sb))
 		return 1;
 
-	t = get_dirent_tail(inode, dirent);
+	t = get_dirent_tail(inode, bh);
 	if (!t) {
 		warn_no_space_for_csum(inode);
 		return 0;
 	}
 
-	if (t->det_checksum != ext4_dirent_csum(inode, dirent,
-						(void *)t - (void *)dirent))
+	if (t->det_checksum != ext4_dirblock_csum(inode, bh->b_data,
+						  (char *)t - bh->b_data))
 		return 0;
 
 	return 1;
 }
 
-static void ext4_dirent_csum_set(struct inode *inode,
-				 struct ext4_dir_entry *dirent)
+static void ext4_dirblock_csum_set(struct inode *inode,
+				 struct buffer_head *bh)
 {
 	struct ext4_dir_entry_tail *t;
 
 	if (!ext4_has_metadata_csum(inode->i_sb))
 		return;
 
-	t = get_dirent_tail(inode, dirent);
+	t = get_dirent_tail(inode, bh);
 	if (!t) {
 		warn_no_space_for_csum(inode);
 		return;
 	}
 
-	t->det_checksum = ext4_dirent_csum(inode, dirent,
-					   (void *)t - (void *)dirent);
+	t->det_checksum = ext4_dirblock_csum(inode, bh->b_data,
+					     (char *)t - bh->b_data);
 }
 
-int ext4_handle_dirty_dirent_node(handle_t *handle,
-				  struct inode *inode,
-				  struct buffer_head *bh)
+int ext4_handle_dirty_dirblock(handle_t *handle,
+			       struct inode *inode,
+			       struct buffer_head *bh)
 {
-	ext4_dirent_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
+	ext4_dirblock_csum_set(inode, bh);
 	return ext4_handle_dirty_metadata(handle, inode, bh);
 }
 
@@ -612,7 +627,7 @@
 		{
 			if (show_names)
 			{
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
+#ifdef CONFIG_FS_ENCRYPTION
 				int len;
 				char *name;
 				struct fscrypt_str fname_crypto_str =
@@ -621,7 +636,7 @@
 
 				name  = de->name;
 				len = de->name_len;
-				if (ext4_encrypted_inode(dir))
+				if (IS_ENCRYPTED(dir))
 					res = fscrypt_get_encryption_info(dir);
 				if (res) {
 					printk(KERN_WARNING "Error setting up"
@@ -629,7 +644,7 @@
 				}
 				if (!fscrypt_has_encryption_key(dir)) {
 					/* Directory is not encrypted */
-					ext4fs_dirhash(de->name,
+					ext4fs_dirhash(dir, de->name,
 						de->name_len, &h);
 					printk("%*.s:(U)%x.%u ", len,
 					       name, h.hash,
@@ -662,8 +677,8 @@
 						name = fname_crypto_str.name;
 						len = fname_crypto_str.len;
 					}
-					ext4fs_dirhash(de->name, de->name_len,
-						       &h);
+					ext4fs_dirhash(dir, de->name,
+						       de->name_len, &h);
 					printk("%*.s:(E)%x.%u ", len, name,
 					       h.hash, (unsigned) ((char *) de
 								   - base));
@@ -673,7 +688,7 @@
 #else
 				int len = de->name_len;
 				char *name = de->name;
-				ext4fs_dirhash(de->name, de->name_len, &h);
+				ext4fs_dirhash(dir, de->name, de->name_len, &h);
 				printk("%*.s:%x.%u ", len, name, h.hash,
 				       (unsigned) ((char *) de - base));
 #endif
@@ -762,7 +777,7 @@
 		hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
 	hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;
 	if (fname && fname_name(fname))
-		ext4fs_dirhash(fname_name(fname), fname_len(fname), hinfo);
+		ext4fs_dirhash(dir, fname_name(fname), fname_len(fname), hinfo);
 	hash = hinfo->hash;
 
 	if (root->info.unused_flags & 1) {
@@ -871,12 +886,15 @@
 {
 	struct dx_root_info *info;
 	int i;
+	unsigned int indirect_levels;
 
 	if (frames[0].bh == NULL)
 		return;
 
 	info = &((struct dx_root *)frames[0].bh->b_data)->info;
-	for (i = 0; i <= info->indirect_levels; i++) {
+	/* save local copy, "info" may be freed after brelse() */
+	indirect_levels = info->indirect_levels;
+	for (i = 0; i <= indirect_levels; i++) {
 		if (frames[i].bh == NULL)
 			break;
 		brelse(frames[i].bh);
@@ -976,7 +994,7 @@
 
 	dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n",
 							(unsigned long)block));
-	bh = ext4_read_dirblock(dir, block, DIRENT);
+	bh = ext4_read_dirblock(dir, block, DIRENT_HTREE);
 	if (IS_ERR(bh))
 		return PTR_ERR(bh);
 
@@ -984,9 +1002,9 @@
 	top = (struct ext4_dir_entry_2 *) ((char *) de +
 					   dir->i_sb->s_blocksize -
 					   EXT4_DIR_REC_LEN(0));
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
+#ifdef CONFIG_FS_ENCRYPTION
 	/* Check if the directory is encrypted */
-	if (ext4_encrypted_inode(dir)) {
+	if (IS_ENCRYPTED(dir)) {
 		err = fscrypt_get_encryption_info(dir);
 		if (err < 0) {
 			brelse(bh);
@@ -1008,14 +1026,14 @@
 			/* silently ignore the rest of the block */
 			break;
 		}
-		ext4fs_dirhash(de->name, de->name_len, hinfo);
+		ext4fs_dirhash(dir, de->name, de->name_len, hinfo);
 		if ((hinfo->hash < start_hash) ||
 		    ((hinfo->hash == start_hash) &&
 		     (hinfo->minor_hash < start_minor_hash)))
 			continue;
 		if (de->inode == 0)
 			continue;
-		if (!ext4_encrypted_inode(dir)) {
+		if (!IS_ENCRYPTED(dir)) {
 			tmp_str.name = de->name;
 			tmp_str.len = de->name_len;
 			err = ext4_htree_store_dirent(dir_file,
@@ -1047,7 +1065,7 @@
 	}
 errout:
 	brelse(bh);
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
+#ifdef CONFIG_FS_ENCRYPTION
 	fscrypt_fname_free_buffer(&fname_crypto_str);
 #endif
 	return count;
@@ -1086,10 +1104,10 @@
 		hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
 		if (ext4_has_inline_data(dir)) {
 			int has_inline_data = 1;
-			count = htree_inlinedir_to_tree(dir_file, dir, 0,
-							&hinfo, start_hash,
-							start_minor_hash,
-							&has_inline_data);
+			count = ext4_inlinedir_to_tree(dir_file, dir, 0,
+						       &hinfo, start_hash,
+						       start_minor_hash,
+						       &has_inline_data);
 			if (has_inline_data) {
 				*next_hash = ~0;
 				return count;
@@ -1197,7 +1215,7 @@
 
 	while ((char *) de < base + blocksize) {
 		if (de->name_len && de->inode) {
-			ext4fs_dirhash(de->name, de->name_len, &h);
+			ext4fs_dirhash(dir, de->name, de->name_len, &h);
 			map_tail--;
 			map_tail->hash = h.hash;
 			map_tail->offs = ((char *) de - base)>>2;
@@ -1252,24 +1270,105 @@
 	dx_set_count(entries, count + 1);
 }
 
+#ifdef CONFIG_UNICODE
+/*
+ * Test whether a case-insensitive directory entry matches the filename
+ * being searched for.  If quick is set, assume the name being looked up
+ * is already in the casefolded form.
+ *
+ * Returns: 0 if the directory entry matches, more than 0 if it
+ * doesn't match or less than zero on error.
+ */
+int ext4_ci_compare(const struct inode *parent, const struct qstr *name,
+		    const struct qstr *entry, bool quick)
+{
+	const struct ext4_sb_info *sbi = EXT4_SB(parent->i_sb);
+	const struct unicode_map *um = sbi->s_encoding;
+	int ret;
+
+	if (quick)
+		ret = utf8_strncasecmp_folded(um, name, entry);
+	else
+		ret = utf8_strncasecmp(um, name, entry);
+
+	if (ret < 0) {
+		/* Handle invalid character sequence as either an error
+		 * or as an opaque byte sequence.
+		 */
+		if (ext4_has_strict_mode(sbi))
+			return -EINVAL;
+
+		if (name->len != entry->len)
+			return 1;
+
+		return !!memcmp(name->name, entry->name, name->len);
+	}
+
+	return ret;
+}
+
+void ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname,
+				  struct fscrypt_str *cf_name)
+{
+	int len;
+
+	if (!IS_CASEFOLDED(dir) || !EXT4_SB(dir->i_sb)->s_encoding) {
+		cf_name->name = NULL;
+		return;
+	}
+
+	cf_name->name = kmalloc(EXT4_NAME_LEN, GFP_NOFS);
+	if (!cf_name->name)
+		return;
+
+	len = utf8_casefold(EXT4_SB(dir->i_sb)->s_encoding,
+			    iname, cf_name->name,
+			    EXT4_NAME_LEN);
+	if (len <= 0) {
+		kfree(cf_name->name);
+		cf_name->name = NULL;
+		return;
+	}
+	cf_name->len = (unsigned) len;
+
+}
+#endif
+
 /*
  * Test whether a directory entry matches the filename being searched for.
  *
  * Return: %true if the directory entry matches, otherwise %false.
  */
-static inline bool ext4_match(const struct ext4_filename *fname,
+static inline bool ext4_match(const struct inode *parent,
+			      const struct ext4_filename *fname,
 			      const struct ext4_dir_entry_2 *de)
 {
 	struct fscrypt_name f;
+#ifdef CONFIG_UNICODE
+	const struct qstr entry = {.name = de->name, .len = de->name_len};
+#endif
 
 	if (!de->inode)
 		return false;
 
 	f.usr_fname = fname->usr_fname;
 	f.disk_name = fname->disk_name;
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
+#ifdef CONFIG_FS_ENCRYPTION
 	f.crypto_buf = fname->crypto_buf;
 #endif
+
+#ifdef CONFIG_UNICODE
+	if (EXT4_SB(parent->i_sb)->s_encoding && IS_CASEFOLDED(parent)) {
+		if (fname->cf_name.name) {
+			struct qstr cf = {.name = fname->cf_name.name,
+					  .len = fname->cf_name.len};
+			return !ext4_ci_compare(parent, &cf, &entry, true);
+		}
+		return !ext4_ci_compare(parent, fname->usr_fname, &entry,
+					false);
+	}
+#endif
+
 	return fscrypt_match_name(&f, de->name, de->name_len);
 }
 
@@ -1290,7 +1389,7 @@
 		/* this code is executed quadratically often */
 		/* do minimal checking `by hand' */
 		if ((char *) de + de->name_len <= dlimit &&
-		    ext4_match(fname, de)) {
+		    ext4_match(dir, fname, de)) {
 			/* found a match - just to be sure, do
 			 * a full check */
 			if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data,
@@ -1327,7 +1426,7 @@
 }
 
 /*
- *	ext4_find_entry()
+ *	__ext4_find_entry()
  *
  * finds an entry in the specified directory with the wanted name. It
  * returns the cache buffer in which the entry was found, and the entry
@@ -1337,39 +1436,32 @@
  * The returned buffer_head has ->b_count elevated.  The caller is expected
  * to brelse() it when appropriate.
  */
-static struct buffer_head * ext4_find_entry (struct inode *dir,
-					const struct qstr *d_name,
-					struct ext4_dir_entry_2 **res_dir,
-					int *inlined)
+static struct buffer_head *__ext4_find_entry(struct inode *dir,
+					     struct ext4_filename *fname,
+					     struct ext4_dir_entry_2 **res_dir,
+					     int *inlined)
 {
 	struct super_block *sb;
 	struct buffer_head *bh_use[NAMEI_RA_SIZE];
 	struct buffer_head *bh, *ret = NULL;
 	ext4_lblk_t start, block;
-	const u8 *name = d_name->name;
+	const u8 *name = fname->usr_fname->name;
 	size_t ra_max = 0;	/* Number of bh's in the readahead
 				   buffer, bh_use[] */
 	size_t ra_ptr = 0;	/* Current index into readahead
 				   buffer */
 	ext4_lblk_t  nblocks;
 	int i, namelen, retval;
-	struct ext4_filename fname;
 
 	*res_dir = NULL;
 	sb = dir->i_sb;
-	namelen = d_name->len;
+	namelen = fname->usr_fname->len;
 	if (namelen > EXT4_NAME_LEN)
 		return NULL;
 
-	retval = ext4_fname_setup_filename(dir, d_name, 1, &fname);
-	if (retval == -ENOENT)
-		return NULL;
-	if (retval)
-		return ERR_PTR(retval);
-
 	if (ext4_has_inline_data(dir)) {
 		int has_inline_data = 1;
-		ret = ext4_find_inline_entry(dir, &fname, res_dir,
+		ret = ext4_find_inline_entry(dir, fname, res_dir,
 					     &has_inline_data);
 		if (has_inline_data) {
 			if (inlined)
@@ -1389,7 +1481,7 @@
 		goto restart;
 	}
 	if (is_dx(dir)) {
-		ret = ext4_dx_find_entry(dir, &fname, res_dir);
+		ret = ext4_dx_find_entry(dir, fname, res_dir);
 		/*
 		 * On success, or if the error was file not found,
 		 * return.  Otherwise, fall back to doing a search the
@@ -1444,8 +1536,7 @@
 		if (!buffer_verified(bh) &&
 		    !is_dx_internal_node(dir, block,
 					 (struct ext4_dir_entry *)bh->b_data) &&
-		    !ext4_dirent_csum_verify(dir,
-				(struct ext4_dir_entry *)bh->b_data)) {
+		    !ext4_dirblock_csum_verify(dir, bh)) {
 			EXT4_ERROR_INODE(dir, "checksumming directory "
 					 "block %lu", (unsigned long)block);
 			brelse(bh);
@@ -1453,7 +1544,7 @@
 			goto cleanup_and_exit;
 		}
 		set_buffer_verified(bh);
-		i = search_dirblock(bh, dir, &fname,
+		i = search_dirblock(bh, dir, fname,
 			    block << EXT4_BLOCK_SIZE_BITS(sb), res_dir);
 		if (i == 1) {
 			EXT4_I(dir)->i_dir_start_lookup = block;
@@ -1484,10 +1575,50 @@
 	/* Clean up the read-ahead blocks */
 	for (; ra_ptr < ra_max; ra_ptr++)
 		brelse(bh_use[ra_ptr]);
-	ext4_fname_free_filename(&fname);
 	return ret;
 }
 
+static struct buffer_head *ext4_find_entry(struct inode *dir,
+					   const struct qstr *d_name,
+					   struct ext4_dir_entry_2 **res_dir,
+					   int *inlined)
+{
+	int err;
+	struct ext4_filename fname;
+	struct buffer_head *bh;
+
+	err = ext4_fname_setup_filename(dir, d_name, 1, &fname);
+	if (err == -ENOENT)
+		return NULL;
+	if (err)
+		return ERR_PTR(err);
+
+	bh = __ext4_find_entry(dir, &fname, res_dir, inlined);
+
+	ext4_fname_free_filename(&fname);
+	return bh;
+}
+
+static struct buffer_head *ext4_lookup_entry(struct inode *dir,
+					     struct dentry *dentry,
+					     struct ext4_dir_entry_2 **res_dir)
+{
+	int err;
+	struct ext4_filename fname;
+	struct buffer_head *bh;
+
+	err = ext4_fname_prepare_lookup(dir, dentry, &fname);
+	if (err == -ENOENT)
+		return NULL;
+	if (err)
+		return ERR_PTR(err);
+
+	bh = __ext4_find_entry(dir, &fname, res_dir, NULL);
+
+	ext4_fname_free_filename(&fname);
+	return bh;
+}
+
 static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
 			struct ext4_filename *fname,
 			struct ext4_dir_entry_2 **res_dir)
@@ -1498,7 +1629,7 @@
 	ext4_lblk_t block;
 	int retval;
 
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
+#ifdef CONFIG_FS_ENCRYPTION
 	*res_dir = NULL;
 #endif
 	frame = dx_probe(fname, dir, NULL, frames);
@@ -1506,7 +1637,7 @@
 		return (struct buffer_head *) frame;
 	do {
 		block = dx_get_block(frame->at);
-		bh = ext4_read_dirblock(dir, block, DIRENT);
+		bh = ext4_read_dirblock(dir, block, DIRENT_HTREE);
 		if (IS_ERR(bh))
 			goto errout;
 
@@ -1546,18 +1677,13 @@
 	struct inode *inode;
 	struct ext4_dir_entry_2 *de;
 	struct buffer_head *bh;
-	int err;
-
-	err = fscrypt_prepare_lookup(dir, dentry, flags);
-	if (err)
-		return ERR_PTR(err);
 
 	if (dentry->d_name.len > EXT4_NAME_LEN)
 		return ERR_PTR(-ENAMETOOLONG);
 
-	bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
+	bh = ext4_lookup_entry(dir, dentry, &de);
 	if (IS_ERR(bh))
-		return (struct dentry *) bh;
+		return ERR_CAST(bh);
 	inode = NULL;
 	if (bh) {
 		__u32 ino = le32_to_cpu(de->inode);
@@ -1571,14 +1697,14 @@
 					 dentry);
 			return ERR_PTR(-EFSCORRUPTED);
 		}
-		inode = ext4_iget_normal(dir->i_sb, ino);
+		inode = ext4_iget(dir->i_sb, ino, EXT4_IGET_NORMAL);
 		if (inode == ERR_PTR(-ESTALE)) {
 			EXT4_ERROR_INODE(dir,
 					 "deleted inode referenced: %u",
 					 ino);
 			return ERR_PTR(-EFSCORRUPTED);
 		}
-		if (!IS_ERR(inode) && ext4_encrypted_inode(dir) &&
+		if (!IS_ERR(inode) && IS_ENCRYPTED(dir) &&
 		    (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) &&
 		    !fscrypt_has_permitted_context(dir, inode)) {
 			ext4_warning(inode->i_sb,
@@ -1588,6 +1714,17 @@
 			return ERR_PTR(-EPERM);
 		}
 	}
+
+#ifdef CONFIG_UNICODE
+	if (!inode && IS_CASEFOLDED(dir)) {
+		/* Eventually we want to call d_add_ci(dentry, NULL)
+		 * for negative dentries in the encoding case as
+		 * well.  For now, prevent the negative dentry
+		 * from being cached.
+		 */
+		return NULL;
+	}
+#endif
 	return d_splice_alias(inode, dentry);
 }
 
@@ -1601,7 +1738,7 @@
 
 	bh = ext4_find_entry(d_inode(child), &dotdot, &de, NULL);
 	if (IS_ERR(bh))
-		return (struct dentry *) bh;
+		return ERR_CAST(bh);
 	if (!bh)
 		return ERR_PTR(-ENOENT);
 	ino = le32_to_cpu(de->inode);
@@ -1613,7 +1750,7 @@
 		return ERR_PTR(-EFSCORRUPTED);
 	}
 
-	return d_obtain_alias(ext4_iget_normal(child->d_sb, ino));
+	return d_obtain_alias(ext4_iget(child->d_sb, ino, EXT4_IGET_NORMAL));
 }
 
 /*
@@ -1683,7 +1820,6 @@
 	char *data1 = (*bh)->b_data, *data2;
 	unsigned split, move, size;
 	struct ext4_dir_entry_2 *de = NULL, *de2;
-	struct ext4_dir_entry_tail *t;
 	int	csum_size = 0;
 	int	err = 0, i;
 
@@ -1744,11 +1880,8 @@
 					    (char *) de2,
 					    blocksize);
 	if (csum_size) {
-		t = EXT4_DIRENT_TAIL(data2, blocksize);
-		initialize_dirent_tail(t, blocksize);
-
-		t = EXT4_DIRENT_TAIL(data1, blocksize);
-		initialize_dirent_tail(t, blocksize);
+		ext4_initialize_dirent_tail(*bh, blocksize);
+		ext4_initialize_dirent_tail(bh2, blocksize);
 	}
 
 	dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1,
@@ -1762,7 +1895,7 @@
 		de = de2;
 	}
 	dx_insert_block(frame, hash2 + continued, newblock);
-	err = ext4_handle_dirty_dirent_node(handle, dir, bh2);
+	err = ext4_handle_dirty_dirblock(handle, dir, bh2);
 	if (err)
 		goto journal_error;
 	err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
@@ -1798,7 +1931,7 @@
 		if (ext4_check_dir_entry(dir, NULL, de, bh,
 					 buf, buf_size, offset))
 			return -EFSCORRUPTED;
-		if (ext4_match(fname, de))
+		if (ext4_match(dir, fname, de))
 			return -EEXIST;
 		nlen = EXT4_DIR_REC_LEN(de->name_len);
 		rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
@@ -1890,7 +2023,7 @@
 	inode_inc_iversion(dir);
 	ext4_mark_inode_dirty(handle, dir);
 	BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
-	err = ext4_handle_dirty_dirent_node(handle, dir, bh);
+	err = ext4_handle_dirty_dirblock(handle, dir, bh);
 	if (err)
 		ext4_std_error(dir->i_sb, err);
 	return 0;
@@ -1909,8 +2042,7 @@
 	struct dx_frame	frames[EXT4_HTREE_LEVEL], *frame;
 	struct dx_entry *entries;
 	struct ext4_dir_entry_2	*de, *de2;
-	struct ext4_dir_entry_tail *t;
-	char		*data1, *top;
+	char		*data2, *top;
 	unsigned	len;
 	int		retval;
 	unsigned	blocksize;
@@ -1950,21 +2082,18 @@
 		return PTR_ERR(bh2);
 	}
 	ext4_set_inode_flag(dir, EXT4_INODE_INDEX);
-	data1 = bh2->b_data;
+	data2 = bh2->b_data;
 
-	memcpy (data1, de, len);
-	de = (struct ext4_dir_entry_2 *) data1;
-	top = data1 + len;
+	memcpy(data2, de, len);
+	de = (struct ext4_dir_entry_2 *) data2;
+	top = data2 + len;
 	while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top)
 		de = de2;
-	de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
-					   (char *) de,
-					   blocksize);
+	de->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -
+					   (char *) de, blocksize);
 
-	if (csum_size) {
-		t = EXT4_DIRENT_TAIL(data1, blocksize);
-		initialize_dirent_tail(t, blocksize);
-	}
+	if (csum_size)
+		ext4_initialize_dirent_tail(bh2, blocksize);
 
 	/* Initialize the root; the dot dirents already exist */
 	de = (struct ext4_dir_entry_2 *) (&root->dotdot);
@@ -1983,7 +2112,7 @@
 	if (fname->hinfo.hash_version <= DX_HASH_TEA)
 		fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
 	fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
-	ext4fs_dirhash(fname_name(fname), fname_len(fname), &fname->hinfo);
+	ext4fs_dirhash(dir, fname_name(fname), fname_len(fname), &fname->hinfo);
 
 	memset(frames, 0, sizeof(frames));
 	frame = frames;
@@ -1994,7 +2123,7 @@
 	retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
 	if (retval)
 		goto out_frames;	
-	retval = ext4_handle_dirty_dirent_node(handle, dir, bh2);
+	retval = ext4_handle_dirty_dirblock(handle, dir, bh2);
 	if (retval)
 		goto out_frames;	
 
@@ -2034,8 +2163,8 @@
 	struct inode *dir = d_inode(dentry->d_parent);
 	struct buffer_head *bh = NULL;
 	struct ext4_dir_entry_2 *de;
-	struct ext4_dir_entry_tail *t;
 	struct super_block *sb;
+	struct ext4_sb_info *sbi;
 	struct ext4_filename fname;
 	int	retval;
 	int	dx_fallback=0;
@@ -2047,10 +2176,17 @@
 		csum_size = sizeof(struct ext4_dir_entry_tail);
 
 	sb = dir->i_sb;
+	sbi = EXT4_SB(sb);
 	blocksize = sb->s_blocksize;
 	if (!dentry->d_name.len)
 		return -EINVAL;
 
+#ifdef CONFIG_UNICODE
+	if (ext4_has_strict_mode(sbi) && IS_CASEFOLDED(dir) &&
+	    sbi->s_encoding && utf8_validate(sbi->s_encoding, &dentry->d_name))
+		return -EINVAL;
+#endif
+
 	retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname);
 	if (retval)
 		return retval;
@@ -2076,6 +2212,11 @@
 	blocks = dir->i_size >> sb->s_blocksize_bits;
 	for (block = 0; block < blocks; block++) {
 		bh = ext4_read_dirblock(dir, block, DIRENT);
+		if (bh == NULL) {
+			bh = ext4_bread(handle, dir, block,
+					EXT4_GET_BLOCKS_CREATE);
+			goto add_to_new_block;
+		}
 		if (IS_ERR(bh)) {
 			retval = PTR_ERR(bh);
 			bh = NULL;
@@ -2096,6 +2237,7 @@
 		brelse(bh);
 	}
 	bh = ext4_append(handle, dir, &block);
+add_to_new_block:
 	if (IS_ERR(bh)) {
 		retval = PTR_ERR(bh);
 		bh = NULL;
@@ -2105,10 +2247,8 @@
 	de->inode = 0;
 	de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize);
 
-	if (csum_size) {
-		t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);
-		initialize_dirent_tail(t, blocksize);
-	}
+	if (csum_size)
+		ext4_initialize_dirent_tail(bh, blocksize);
 
 	retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh);
 out:
@@ -2140,7 +2280,7 @@
 		return PTR_ERR(frame);
 	entries = frame->entries;
 	at = frame->at;
-	bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT);
+	bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT_HTREE);
 	if (IS_ERR(bh)) {
 		err = PTR_ERR(bh);
 		bh = NULL;
@@ -2262,7 +2402,7 @@
 			dxroot->info.indirect_levels += 1;
 			dxtrace(printk(KERN_DEBUG
 				       "Creating %d level index...\n",
-				       info->indirect_levels));
+				       dxroot->info.indirect_levels));
 			err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
 			if (err)
 				goto journal_error;
@@ -2366,7 +2506,7 @@
 		goto out;
 
 	BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
-	err = ext4_handle_dirty_dirent_node(handle, dir, bh);
+	err = ext4_handle_dirty_dirblock(handle, dir, bh);
 	if (unlikely(err))
 		goto out;
 
@@ -2568,7 +2708,6 @@
 {
 	struct buffer_head *dir_block = NULL;
 	struct ext4_dir_entry_2 *de;
-	struct ext4_dir_entry_tail *t;
 	ext4_lblk_t block = 0;
 	unsigned int blocksize = dir->i_sb->s_blocksize;
 	int csum_size = 0;
@@ -2592,13 +2731,11 @@
 	de = (struct ext4_dir_entry_2 *)dir_block->b_data;
 	ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0);
 	set_nlink(inode, 2);
-	if (csum_size) {
-		t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize);
-		initialize_dirent_tail(t, blocksize);
-	}
+	if (csum_size)
+		ext4_initialize_dirent_tail(dir_block, blocksize);
 
 	BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
-	err = ext4_handle_dirty_dirent_node(handle, inode, dir_block);
+	err = ext4_handle_dirty_dirblock(handle, inode, dir_block);
 	if (err)
 		goto out;
 	set_buffer_verified(dir_block);
@@ -2688,7 +2825,10 @@
 		EXT4_ERROR_INODE(inode, "invalid size");
 		return true;
 	}
-	bh = ext4_read_dirblock(inode, 0, EITHER);
+	/* The first directory block must not be a hole,
+	 * so treat it as DIRENT_HTREE
+	 */
+	bh = ext4_read_dirblock(inode, 0, DIRENT_HTREE);
 	if (IS_ERR(bh))
 		return true;
 
@@ -2710,6 +2850,10 @@
 			brelse(bh);
 			lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb);
 			bh = ext4_read_dirblock(inode, lblock, EITHER);
+			if (bh == NULL) {
+				offset += sb->s_blocksize;
+				continue;
+			}
 			if (IS_ERR(bh))
 				return true;
 			de = (struct ext4_dir_entry_2 *) bh->b_data;
@@ -2975,6 +3119,17 @@
 	ext4_update_dx_flag(dir);
 	ext4_mark_inode_dirty(handle, dir);
 
+#ifdef CONFIG_UNICODE
+	/* VFS negative dentries are incompatible with Encoding and
+	 * Case-insensitiveness. Eventually we'll want avoid
+	 * invalidating the dentries here, alongside with returning the
+	 * negative dentries at ext4_lookup(), when it is better
+	 * supported by the VFS for the CI case.
+	 */
+	if (IS_CASEFOLDED(dir))
+		d_invalidate(dentry);
+#endif
+
 end_rmdir:
 	brelse(bh);
 	if (handle)
@@ -3044,6 +3199,17 @@
 	inode->i_ctime = current_time(inode);
 	ext4_mark_inode_dirty(handle, inode);
 
+#ifdef CONFIG_UNICODE
+	/* VFS negative dentries are incompatible with Encoding and
+	 * Case-insensitiveness. Eventually we'll want avoid
+	 * invalidating the dentries here, alongside with returning the
+	 * negative dentries at ext4_lookup(), when it is  better
+	 * supported by the VFS for the CI case.
+	 */
+	if (IS_CASEFOLDED(dir))
+		d_invalidate(dentry);
+#endif
+
 end_unlink:
 	brelse(bh);
 	if (handle)
@@ -3253,7 +3419,10 @@
 	struct buffer_head *bh;
 
 	if (!ext4_has_inline_data(inode)) {
-		bh = ext4_read_dirblock(inode, 0, EITHER);
+		/* The first directory block must not be a hole, so
+		 * treat it as DIRENT_HTREE
+		 */
+		bh = ext4_read_dirblock(inode, 0, DIRENT_HTREE);
 		if (IS_ERR(bh)) {
 			*retval = PTR_ERR(bh);
 			return NULL;
@@ -3314,9 +3483,8 @@
 							   ent->inode,
 							   ent->dir_bh);
 		} else {
-			retval = ext4_handle_dirty_dirent_node(handle,
-							       ent->inode,
-							       ent->dir_bh);
+			retval = ext4_handle_dirty_dirblock(handle, ent->inode,
+							    ent->dir_bh);
 		}
 	} else {
 		retval = ext4_mark_inode_dirty(handle, ent->inode);
@@ -3346,8 +3514,7 @@
 	ext4_mark_inode_dirty(handle, ent->dir);
 	BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata");
 	if (!ent->inlined) {
-		retval = ext4_handle_dirty_dirent_node(handle,
-						       ent->dir, ent->bh);
+		retval = ext4_handle_dirty_dirblock(handle, ent->dir, ent->bh);
 		if (unlikely(retval)) {
 			ext4_std_error(ent->dir->i_sb, retval);
 			return retval;