X-Git-Url: http://git.osdn.net/view?a=blobdiff_plain;f=libexfat%2Fnode.c;h=4a3ee40c5f96259354e658196b4efed0c71f235a;hb=74ab25d6e5994adda78c342b949a8eda35b27b39;hp=15ce5978efad314310f377e7847a39ca8481c919;hpb=33f510a9e0c9db400e080be78cac158fcc30e0a9;p=android-x86%2Fexternal-exfat.git

diff --git a/libexfat/node.c b/libexfat/node.c
index 15ce597..4a3ee40 100644
--- a/libexfat/node.c
+++ b/libexfat/node.c
@@ -1,11 +1,24 @@
 /*
- *  node.c
- *  exFAT file system implementation library.
- *
- *  Created by Andrew Nayenko on 09.10.09.
- *  This software is distributed under the GNU General Public License 
- *  version 3 or any later.
- */
+	node.c (09.10.09)
+	exFAT file system implementation library.
+
+	Free exFAT implementation.
+	Copyright (C) 2010-2016  Andrew Nayenko
+
+	This program is free software; you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 2 of the License, or
+	(at your option) any later version.
+
+	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.
+
+	You should have received a copy of the GNU General Public License along
+	with this program; if not, write to the Free Software Foundation, Inc.,
+	51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
 
 #include "exfat.h"
 #include <errno.h>
@@ -17,7 +30,6 @@ struct iterator
 {
 	cluster_t cluster;
 	off_t offset;
-	int contiguous;
 	char* chunk;
 };
 
@@ -29,35 +41,218 @@ struct exfat_node* exfat_get_node(struct exfat_node* node)
 	return node;
 }
 
-void exfat_put_node(struct exfat_node* node)
+void exfat_put_node(struct exfat* ef, struct exfat_node* node)
 {
-	if (--node->references < 0)
+	char buffer[UTF8_BYTES(EXFAT_NAME_MAX) + 1];
+
+	--node->references;
+	if (node->references < 0)
 	{
-		char buffer[EXFAT_NAME_MAX + 1];
-		exfat_get_name(node, buffer, EXFAT_NAME_MAX);
-		exfat_bug("reference counter of `%s' is below zero", buffer);
+		exfat_get_name(node, buffer, sizeof(buffer) - 1);
+		exfat_bug("reference counter of '%s' is below zero", buffer);
+	}
+	else if (node->references == 0 && node != ef->root)
+	{
+		if (node->flags & EXFAT_ATTRIB_DIRTY)
+		{
+			exfat_get_name(node, buffer, sizeof(buffer) - 1);
+			exfat_warn("dirty node '%s' with zero references", buffer);
+		}
 	}
 }
 
-static void opendir(const struct exfat_node* dir, struct iterator* it)
+/**
+ * This function must be called on rmdir and unlink (after the last
+ * exfat_put_node()) to free clusters.
+ */
+int exfat_cleanup_node(struct exfat* ef, struct exfat_node* node)
 {
+	int rc = 0;
+
+	if (node->references != 0)
+		exfat_bug("unable to cleanup a node with %d references",
+				node->references);
+
+	if (node->flags & EXFAT_ATTRIB_UNLINKED)
+	{
+		/* free all clusters and node structure itself */
+		rc = exfat_truncate(ef, node, 0, true);
+		/* free the node even in case of error or its memory will be lost */
+		free(node);
+	}
+	return rc;
+}
+
+/**
+ * Cluster + offset from the beginning of the directory to absolute offset.
+ */
+static off_t co2o(struct exfat* ef, cluster_t cluster, off_t offset)
+{
+	return exfat_c2o(ef, cluster) + offset % CLUSTER_SIZE(*ef->sb);
+}
+
+static int opendir(struct exfat* ef, const struct exfat_node* dir,
+		struct iterator* it)
+{
+	char buffer[UTF8_BYTES(EXFAT_NAME_MAX) + 1];
+
 	if (!(dir->flags & EXFAT_ATTRIB_DIR))
-		exfat_bug("`%s' is not a directory", dir->name);
+	{
+		exfat_get_name(dir, buffer, sizeof(buffer) - 1);
+		exfat_bug("'%s' is not a directory", buffer);
+	}
 	it->cluster = dir->start_cluster;
 	it->offset = 0;
-	it->contiguous = IS_CONTIGUOUS(*dir);
-	it->chunk = NULL;
+	it->chunk = malloc(CLUSTER_SIZE(*ef->sb));
+	if (it->chunk == NULL)
+	{
+		exfat_error("failed to allocate memory for directory cluster");
+		return -ENOMEM;
+	}
+	if (exfat_pread(ef->dev, it->chunk, CLUSTER_SIZE(*ef->sb),
+			exfat_c2o(ef, it->cluster)) < 0)
+	{
+		free(it->chunk);
+		exfat_get_name(dir, buffer, sizeof(buffer) - 1);
+		exfat_error("failed to read '%s' directory cluster %#x", buffer,
+				it->cluster);
+		return -EIO;
+	}
+	return 0;
 }
 
 static void closedir(struct iterator* it)
 {
 	it->cluster = 0;
 	it->offset = 0;
-	it->contiguous = 0;
 	free(it->chunk);
 	it->chunk = NULL;
 }
 
+static bool fetch_next_entry(struct exfat* ef, const struct exfat_node* parent,
+		struct iterator* it)
+{
+	/* move iterator to the next entry in the directory */
+	it->offset += sizeof(struct exfat_entry);
+	/* fetch the next cluster if needed */
+	if ((it->offset & (CLUSTER_SIZE(*ef->sb) - 1)) == 0)
+	{
+		/* reached the end of directory; the caller should check this
+		   condition too */
+		if (it->offset >= parent->size)
+			return true;
+		it->cluster = exfat_next_cluster(ef, parent, it->cluster);
+		if (CLUSTER_INVALID(it->cluster))
+		{
+			exfat_error("invalid cluster 0x%x while reading directory",
+					it->cluster);
+			return false;
+		}
+		if (exfat_pread(ef->dev, it->chunk, CLUSTER_SIZE(*ef->sb),
+				exfat_c2o(ef, it->cluster)) < 0)
+		{
+			exfat_error("failed to read the next directory cluster %#x",
+					it->cluster);
+			return false;
+		}
+	}
+	return true;
+}
+
+static struct exfat_node* allocate_node(void)
+{
+	struct exfat_node* node = malloc(sizeof(struct exfat_node));
+	if (node == NULL)
+	{
+		exfat_error("failed to allocate node");
+		return NULL;
+	}
+	memset(node, 0, sizeof(struct exfat_node));
+	return node;
+}
+
+static void init_node_meta1(struct exfat_node* node,
+		const struct exfat_entry_meta1* meta1)
+{
+	node->flags = le16_to_cpu(meta1->attrib);
+	node->mtime = exfat_exfat2unix(meta1->mdate, meta1->mtime,
+			meta1->mtime_cs);
+	/* there is no centiseconds field for atime */
+	node->atime = exfat_exfat2unix(meta1->adate, meta1->atime, 0);
+}
+
+static void init_node_meta2(struct exfat_node* node,
+		const struct exfat_entry_meta2* meta2)
+{
+	node->size = le64_to_cpu(meta2->size);
+	node->start_cluster = le32_to_cpu(meta2->start_cluster);
+	node->fptr_cluster = node->start_cluster;
+	if (meta2->flags & EXFAT_FLAG_CONTIGUOUS)
+		node->flags |= EXFAT_ATTRIB_CONTIGUOUS;
+}
+
+static const struct exfat_entry* get_entry_ptr(const struct exfat* ef,
+		const struct iterator* it)
+{
+	return (const struct exfat_entry*)
+			(it->chunk + it->offset % CLUSTER_SIZE(*ef->sb));
+}
+
+static bool check_node(const struct exfat_node* node, uint16_t actual_checksum,
+		uint16_t reference_checksum, uint64_t valid_size)
+{
+	char buffer[UTF8_BYTES(EXFAT_NAME_MAX) + 1];
+	bool ret = true;
+
+	/*
+	   Validate checksum first. If it's invalid all other fields probably
+	   contain just garbage.
+	*/
+	if (actual_checksum != reference_checksum)
+	{
+		exfat_get_name(node, buffer, sizeof(buffer) - 1);
+		exfat_error("'%s' has invalid checksum (%#hx != %#hx)", buffer,
+				actual_checksum, reference_checksum);
+		ret = false;
+	}
+
+	/*
+	   exFAT does not support sparse files but allows files with uninitialized
+	   clusters. For such files valid_size means initialized data size and
+	   cannot be greater than file size. See SetFileValidData() function
+	   description in MSDN.
+	*/
+	if (valid_size > node->size)
+	{
+		exfat_get_name(node, buffer, sizeof(buffer) - 1);
+		exfat_error("'%s' has valid size (%"PRIu64") greater than size "
+				"(%"PRIu64")", buffer, valid_size, node->size);
+		ret = false;
+	}
+
+	return ret;
+}
+
+static void decompress_upcase(uint16_t* output, const le16_t* source,
+		size_t size)
+{
+	size_t si;
+	size_t oi;
+
+	for (oi = 0; oi < EXFAT_UPCASE_CHARS; oi++)
+		output[oi] = oi;
+
+	for (si = 0, oi = 0; si < size && oi < EXFAT_UPCASE_CHARS; si++)
+	{
+		uint16_t ch = le16_to_cpu(source[si]);
+
+		if (ch == 0xffff && si + 1 < size)	/* indicates a run */
+			oi += le16_to_cpu(source[++si]);
+		else
+			output[oi++] = ch;
+	}
+}
+
 /*
  * Reads one entry in directory at position pointed by iterator and fills
  * node structure.
@@ -65,52 +260,39 @@ static void closedir(struct iterator* it)
 static int readdir(struct exfat* ef, const struct exfat_node* parent,
 		struct exfat_node** node, struct iterator* it)
 {
+	int rc = -EIO;
 	const struct exfat_entry* entry;
-	const struct exfat_file* file;
-	const struct exfat_file_info* file_info;
-	const struct exfat_file_name* file_name;
-	const struct exfat_upcase* upcase;
-	const struct exfat_bitmap* bitmap;
-	const struct exfat_label* label;
+	const struct exfat_entry_meta1* meta1;
+	const struct exfat_entry_meta2* meta2;
+	const struct exfat_entry_name* file_name;
+	const struct exfat_entry_upcase* upcase;
+	const struct exfat_entry_bitmap* bitmap;
+	const struct exfat_entry_label* label;
 	uint8_t continuations = 0;
 	le16_t* namep = NULL;
 	uint16_t reference_checksum = 0;
 	uint16_t actual_checksum = 0;
+	uint64_t valid_size = 0;
+	uint64_t upcase_size = 0;
+	le16_t* upcase_comp = NULL;
 
 	*node = NULL;
 
-	if (it->chunk == NULL)
-	{
-		it->chunk = malloc(CLUSTER_SIZE(*ef->sb));
-		if (it->chunk == NULL)
-		{
-			exfat_error("out of memory");
-			return -ENOMEM;
-		}
-		exfat_read_raw(it->chunk, CLUSTER_SIZE(*ef->sb),
-				exfat_c2o(ef, it->cluster), ef->fd);
-	}
-
 	for (;;)
 	{
-		/* every directory (even empty one) occupies at least one cluster and
-		   must contain EOD entry */
-		entry = (const struct exfat_entry*)
-				(it->chunk + it->offset % CLUSTER_SIZE(*ef->sb));
-		/* move iterator to the next entry in the directory */
-		it->offset += sizeof(struct exfat_entry);
-
-		switch (entry->type)
+		if (it->offset >= parent->size)
 		{
-		case EXFAT_ENTRY_EOD:
 			if (continuations != 0)
 			{
-				exfat_error("expected %hhu continuations before EOD",
-						continuations);
+				exfat_error("expected %hhu continuations", continuations);
 				goto error;
 			}
 			return -ENOENT; /* that's OK, means end of directory */
+		}
 
+		entry = get_entry_ptr(ef, it);
+		switch (entry->type)
+		{
 		case EXFAT_ENTRY_FILE:
 			if (continuations != 0)
 			{
@@ -118,31 +300,33 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 						continuations);
 				goto error;
 			}
-			file = (const struct exfat_file*) entry;
-			continuations = file->continuations;
+			meta1 = (const struct exfat_entry_meta1*) entry;
+			continuations = meta1->continuations;
 			/* each file entry must have at least 2 continuations:
 			   info and name */
 			if (continuations < 2)
 			{
 				exfat_error("too few continuations (%hhu)", continuations);
-				return -EIO;
+				goto error;
+			}
+			if (continuations > 1 +
+					DIV_ROUND_UP(EXFAT_NAME_MAX, EXFAT_ENAME_MAX))
+			{
+				exfat_error("too many continuations (%hhu)", continuations);
+				goto error;
 			}
-			reference_checksum = le16_to_cpu(file->checksum);
-			actual_checksum = exfat_start_checksum(file);
-			*node = malloc(sizeof(struct exfat_node));
+			reference_checksum = le16_to_cpu(meta1->checksum);
+			actual_checksum = exfat_start_checksum(meta1);
+			*node = allocate_node();
 			if (*node == NULL)
 			{
-				exfat_error("failed to allocate node");
-				return -ENOMEM;
+				rc = -ENOMEM;
+				goto error;
 			}
-			memset(*node, 0, sizeof(struct exfat_node));
 			/* new node has zero reference counter */
-			(*node)->meta1_offset = exfat_c2o(ef, it->cluster) +
-					(it->offset - sizeof(struct exfat_entry)) %
-					CLUSTER_SIZE(*ef->sb);
-			(*node)->flags = le16_to_cpu(file->attrib);
-			(*node)->mtime = exfat_exfat2unix(file->mdate, file->mtime);
-			(*node)->atime = exfat_exfat2unix(file->adate, file->atime);
+			(*node)->entry_cluster = it->cluster;
+			(*node)->entry_offset = it->offset;
+			init_node_meta1(*node, meta1);
 			namep = (*node)->name;
 			break;
 
@@ -153,27 +337,30 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 						continuations);
 				goto error;
 			}
-			file_info = (const struct exfat_file_info*) entry;
+			meta2 = (const struct exfat_entry_meta2*) entry;
+			if (meta2->flags & ~(EXFAT_FLAG_ALWAYS1 | EXFAT_FLAG_CONTIGUOUS))
+			{
+				exfat_error("unknown flags in meta2 (0x%hhx)", meta2->flags);
+				goto error;
+			}
+			init_node_meta2(*node, meta2);
 			actual_checksum = exfat_add_checksum(entry, actual_checksum);
-			(*node)->meta2_offset = exfat_c2o(ef, it->cluster) +
-					(it->offset - sizeof(struct exfat_entry)) %
-					CLUSTER_SIZE(*ef->sb);
-			(*node)->size = le64_to_cpu(file_info->size);
+			valid_size = le64_to_cpu(meta2->valid_size);
+			/* empty files must be marked as non-contiguous */
+			if ((*node)->size == 0 && (meta2->flags & EXFAT_FLAG_CONTIGUOUS))
+			{
+				exfat_error("empty file marked as contiguous (0x%hhx)",
+						meta2->flags);
+				goto error;
+			}
 			/* directories must be aligned on at cluster boundary */
 			if (((*node)->flags & EXFAT_ATTRIB_DIR) &&
 				(*node)->size % CLUSTER_SIZE(*ef->sb) != 0)
 			{
-				char buffer[EXFAT_NAME_MAX + 1];
-
-				exfat_get_name(*node, buffer, EXFAT_NAME_MAX);
-				exfat_error("directory `%s' has invalid size %"PRIu64" bytes",
-						buffer, (*node)->size);
+				exfat_error("directory has invalid size %"PRIu64" bytes",
+						(*node)->size);
 				goto error;
 			}
-			(*node)->start_cluster = le32_to_cpu(file_info->start_cluster);
-			(*node)->fptr_cluster = (*node)->start_cluster;
-			if (file_info->flag == EXFAT_FLAG_CONTIGUOUS)
-				(*node)->flags |= EXFAT_ATTRIB_CONTIGUOUS;
 			--continuations;
 			break;
 
@@ -183,19 +370,21 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 				exfat_error("unexpected continuation");
 				goto error;
 			}
-			file_name = (const struct exfat_file_name*) entry;
+			file_name = (const struct exfat_entry_name*) entry;
 			actual_checksum = exfat_add_checksum(entry, actual_checksum);
 
-			memcpy(namep, file_name->name, EXFAT_ENAME_MAX * sizeof(le16_t));
+			memcpy(namep, file_name->name,
+					MIN(EXFAT_ENAME_MAX,
+						((*node)->name + EXFAT_NAME_MAX - namep)) *
+					sizeof(le16_t));
 			namep += EXFAT_ENAME_MAX;
 			if (--continuations == 0)
 			{
-				if (actual_checksum != reference_checksum)
-				{
-					exfat_error("invalid checksum (0x%hx != 0x%hx)",
-							actual_checksum, reference_checksum);
-					return -EIO;
-				}
+				if (!check_node(*node, actual_checksum, reference_checksum,
+						valid_size))
+					goto error;
+				if (!fetch_next_entry(ef, parent, it))
+					goto error;
 				return 0; /* entry completed */
 			}
 			break;
@@ -203,100 +392,138 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 		case EXFAT_ENTRY_UPCASE:
 			if (ef->upcase != NULL)
 				break;
-			upcase = (const struct exfat_upcase*) entry;
+			upcase = (const struct exfat_entry_upcase*) entry;
 			if (CLUSTER_INVALID(le32_to_cpu(upcase->start_cluster)))
 			{
-				exfat_error("invalid cluster in upcase table");
-				return -EIO;
+				exfat_error("invalid cluster 0x%x in upcase table",
+						le32_to_cpu(upcase->start_cluster));
+				goto error;
 			}
-			if (le64_to_cpu(upcase->size) == 0 ||
-				le64_to_cpu(upcase->size) > 0xffff * sizeof(uint16_t) ||
-				le64_to_cpu(upcase->size) % sizeof(uint16_t) != 0)
+			upcase_size = le64_to_cpu(upcase->size);
+			if (upcase_size == 0 ||
+				upcase_size > EXFAT_UPCASE_CHARS * sizeof(uint16_t) ||
+				upcase_size % sizeof(uint16_t) != 0)
 			{
 				exfat_error("bad upcase table size (%"PRIu64" bytes)",
-						le64_to_cpu(upcase->size));
-				return -EIO;
+						upcase_size);
+				goto error;
 			}
-			ef->upcase = malloc(le64_to_cpu(upcase->size));
-			if (ef->upcase == NULL)
+			upcase_comp = malloc(upcase_size);
+			if (upcase_comp == NULL)
 			{
 				exfat_error("failed to allocate upcase table (%"PRIu64" bytes)",
-						le64_to_cpu(upcase->size));
-				return -ENOMEM;
+						upcase_size);
+				rc = -ENOMEM;
+				goto error;
 			}
-			ef->upcase_chars = le64_to_cpu(upcase->size) / sizeof(le16_t);
 
-			exfat_read_raw(ef->upcase, le64_to_cpu(upcase->size),
-					exfat_c2o(ef, le32_to_cpu(upcase->start_cluster)), ef->fd);
+			/* read compressed upcase table */
+			if (exfat_pread(ef->dev, upcase_comp, upcase_size,
+					exfat_c2o(ef, le32_to_cpu(upcase->start_cluster))) < 0)
+			{
+				free(upcase_comp);
+				exfat_error("failed to read upper case table "
+						"(%"PRIu64" bytes starting at cluster %#x)",
+						upcase_size,
+						le32_to_cpu(upcase->start_cluster));
+				goto error;
+			}
+
+			/* decompress upcase table */
+			ef->upcase = calloc(EXFAT_UPCASE_CHARS, sizeof(uint16_t));
+			if (ef->upcase == NULL)
+			{
+				free(upcase_comp);
+				exfat_error("failed to allocate decompressed upcase table");
+				rc = -ENOMEM;
+				goto error;
+			}
+			decompress_upcase(ef->upcase, upcase_comp,
+					upcase_size / sizeof(uint16_t));
+			free(upcase_comp);
 			break;
 
 		case EXFAT_ENTRY_BITMAP:
-			bitmap = (const struct exfat_bitmap*) entry;
-			if (CLUSTER_INVALID(le32_to_cpu(bitmap->start_cluster)))
+			bitmap = (const struct exfat_entry_bitmap*) entry;
+			ef->cmap.start_cluster = le32_to_cpu(bitmap->start_cluster);
+			if (CLUSTER_INVALID(ef->cmap.start_cluster))
 			{
-				exfat_error("invalid cluster in clusters bitmap");
- 				return -EIO;
+				exfat_error("invalid cluster 0x%x in clusters bitmap",
+						ef->cmap.start_cluster);
+				goto error;
 			}
 			ef->cmap.size = le32_to_cpu(ef->sb->cluster_count) -
 				EXFAT_FIRST_DATA_CLUSTER;
-			if (le64_to_cpu(bitmap->size) != (ef->cmap.size + 7) / 8)
+			if (le64_to_cpu(bitmap->size) < DIV_ROUND_UP(ef->cmap.size, 8))
 			{
-				exfat_error("invalid bitmap size: %"PRIu64" (expected %u)",
-						le64_to_cpu(bitmap->size), (ef->cmap.size + 7) / 8);
-				return -EIO;
+				exfat_error("invalid clusters bitmap size: %"PRIu64
+						" (expected at least %u)",
+						le64_to_cpu(bitmap->size),
+						DIV_ROUND_UP(ef->cmap.size, 8));
+				goto error;
 			}
-			ef->cmap.start_cluster = le32_to_cpu(bitmap->start_cluster);
 			/* FIXME bitmap can be rather big, up to 512 MB */
 			ef->cmap.chunk_size = ef->cmap.size;
-			ef->cmap.chunk = malloc(le64_to_cpu(bitmap->size));
+			ef->cmap.chunk = malloc(BMAP_SIZE(ef->cmap.chunk_size));
 			if (ef->cmap.chunk == NULL)
 			{
-				exfat_error("failed to allocate clusters map chunk "
+				exfat_error("failed to allocate clusters bitmap chunk "
 						"(%"PRIu64" bytes)", le64_to_cpu(bitmap->size));
-				return -ENOMEM;
+				rc = -ENOMEM;
+				goto error;
 			}
 
-			exfat_read_raw(ef->cmap.chunk, le64_to_cpu(bitmap->size),
-					exfat_c2o(ef, ef->cmap.start_cluster), ef->fd);
+			if (exfat_pread(ef->dev, ef->cmap.chunk,
+					BMAP_SIZE(ef->cmap.chunk_size),
+					exfat_c2o(ef, ef->cmap.start_cluster)) < 0)
+			{
+				exfat_error("failed to read clusters bitmap "
+						"(%"PRIu64" bytes starting at cluster %#x)",
+						le64_to_cpu(bitmap->size), ef->cmap.start_cluster);
+				goto error;
+			}
 			break;
 
 		case EXFAT_ENTRY_LABEL:
-			label = (const struct exfat_label*) entry;
+			label = (const struct exfat_entry_label*) entry;
 			if (label->length > EXFAT_ENAME_MAX)
 			{
 				exfat_error("too long label (%hhu chars)", label->length);
-				return -EIO;
+				goto error;
 			}
+			if (utf16_to_utf8(ef->label, label->name,
+						sizeof(ef->label) - 1, EXFAT_ENAME_MAX) != 0)
+				goto error;
 			break;
 
 		default:
-			if (entry->type & EXFAT_ENTRY_VALID)
+			if (!(entry->type & EXFAT_ENTRY_VALID))
+				break; /* deleted entry, ignore it */
+			if (!(entry->type & EXFAT_ENTRY_OPTIONAL))
 			{
-				exfat_error("unknown entry type 0x%hhu", entry->type);
+				exfat_error("unknown entry type %#hhx", entry->type);
 				goto error;
 			}
-			break;
-		}
-
-		/* fetch the next cluster if needed */
-		if ((it->offset & (CLUSTER_SIZE(*ef->sb) - 1)) == 0)
-		{
-			it->cluster = exfat_next_cluster(ef, parent, it->cluster);
-			if (CLUSTER_INVALID(it->cluster))
+			/* optional entry, warn and skip */
+			exfat_warn("unknown entry type %#hhx", entry->type);
+			if (continuations == 0)
 			{
-				exfat_error("invalid cluster while reading directory");
+				exfat_error("unexpected continuation");
 				goto error;
 			}
-			exfat_read_raw(it->chunk, CLUSTER_SIZE(*ef->sb),
-					exfat_c2o(ef, it->cluster), ef->fd);
+			--continuations;
+			break;
 		}
+
+		if (!fetch_next_entry(ef, parent, it))
+			goto error;
 	}
 	/* we never reach here */
 
 error:
 	free(*node);
 	*node = NULL;
-	return -EIO;
+	return rc;
 }
 
 int exfat_cache_directory(struct exfat* ef, struct exfat_node* dir)
@@ -309,9 +536,12 @@ int exfat_cache_directory(struct exfat* ef, struct exfat_node* dir)
 	if (dir->flags & EXFAT_ATTRIB_CACHED)
 		return 0; /* already cached */
 
-	opendir(dir, &it);
+	rc = opendir(ef, dir, &it);
+	if (rc != 0)
+		return rc;
 	while ((rc = readdir(ef, dir, &node, &it)) == 0)
 	{
+		node->parent = dir;
 		if (current != NULL)
 		{
 			current->next = node;
@@ -340,67 +570,730 @@ int exfat_cache_directory(struct exfat* ef, struct exfat_node* dir)
 	return 0;
 }
 
-static void reset_cache(struct exfat_node* node)
+static void tree_attach(struct exfat_node* dir, struct exfat_node* node)
+{
+	node->parent = dir;
+	if (dir->child)
+	{
+		dir->child->prev = node;
+		node->next = dir->child;
+	}
+	dir->child = node;
+}
+
+static void tree_detach(struct exfat_node* node)
+{
+	if (node->prev)
+		node->prev->next = node->next;
+	else /* this is the first node in the list */
+		node->parent->child = node->next;
+	if (node->next)
+		node->next->prev = node->prev;
+	node->parent = NULL;
+	node->prev = NULL;
+	node->next = NULL;
+}
+
+static void reset_cache(struct exfat* ef, struct exfat_node* node)
 {
-	struct exfat_node* child;
-	struct exfat_node* next;
+	char buffer[UTF8_BYTES(EXFAT_NAME_MAX) + 1];
 
-	for (child = node->child; child; child = next)
+	while (node->child)
 	{
-		reset_cache(child);
-		next = child->next;
-		free(child);
+		struct exfat_node* p = node->child;
+		reset_cache(ef, p);
+		tree_detach(p);
+		free(p);
 	}
+	node->flags &= ~EXFAT_ATTRIB_CACHED;
 	if (node->references != 0)
 	{
-		char buffer[EXFAT_NAME_MAX + 1];
-		exfat_get_name(node, buffer, EXFAT_NAME_MAX);
-		exfat_warn("non-zero reference counter (%d) for `%s'",
+		exfat_get_name(node, buffer, sizeof(buffer) - 1);
+		exfat_warn("non-zero reference counter (%d) for '%s'",
 				node->references, buffer);
 	}
-	node->child = NULL;
-	node->flags &= ~EXFAT_ATTRIB_CACHED;
+	if (node != ef->root && (node->flags & EXFAT_ATTRIB_DIRTY))
+	{
+		exfat_get_name(node, buffer, sizeof(buffer) - 1);
+		exfat_bug("node '%s' is dirty", buffer);
+	}
+	while (node->references)
+		exfat_put_node(ef, node);
 }
 
 void exfat_reset_cache(struct exfat* ef)
 {
-	reset_cache(ef->root);
+	reset_cache(ef, ef->root);
+}
+
+static bool next_entry(struct exfat* ef, const struct exfat_node* parent,
+		cluster_t* cluster, off_t* offset)
+{
+	*offset += sizeof(struct exfat_entry);
+	if (*offset % CLUSTER_SIZE(*ef->sb) == 0)
+	{
+		*cluster = exfat_next_cluster(ef, parent, *cluster);
+		if (CLUSTER_INVALID(*cluster))
+		{
+			exfat_error("invalid cluster %#x while getting next entry",
+					*cluster);
+			return false;
+		}
+	}
+	return true;
 }
 
-void exfat_flush_node(struct exfat* ef, const struct exfat_node* node)
+int exfat_flush_node(struct exfat* ef, struct exfat_node* node)
 {
-	struct exfat_file meta1;
-	struct exfat_file_info meta2;
-	uint16_t checksum;
-	uint8_t i;
+	cluster_t cluster;
+	off_t offset;
+	off_t meta1_offset, meta2_offset;
+	struct exfat_entry_meta1 meta1;
+	struct exfat_entry_meta2 meta2;
+
+	if (!(node->flags & EXFAT_ATTRIB_DIRTY))
+		return 0; /* no need to flush */
 
-	exfat_read_raw(&meta1, sizeof(meta1), node->meta1_offset, ef->fd);
+	if (ef->ro)
+		exfat_bug("unable to flush node to read-only FS");
+
+	if (node->parent == NULL)
+		return 0; /* do not flush unlinked node */
+
+	cluster = node->entry_cluster;
+	offset = node->entry_offset;
+	meta1_offset = co2o(ef, cluster, offset);
+	if (!next_entry(ef, node->parent, &cluster, &offset))
+		return -EIO;
+	meta2_offset = co2o(ef, cluster, offset);
+
+	if (exfat_pread(ef->dev, &meta1, sizeof(meta1), meta1_offset) < 0)
+	{
+		exfat_error("failed to read meta1 entry on flush");
+		return -EIO;
+	}
 	if (meta1.type != EXFAT_ENTRY_FILE)
 		exfat_bug("invalid type of meta1: 0x%hhx", meta1.type);
 	meta1.attrib = cpu_to_le16(node->flags);
-	exfat_unix2exfat(node->mtime, &meta1.mdate, &meta1.mtime);
-	exfat_unix2exfat(node->atime, &meta1.adate, &meta1.atime);
+	exfat_unix2exfat(node->mtime, &meta1.mdate, &meta1.mtime, &meta1.mtime_cs);
+	exfat_unix2exfat(node->atime, &meta1.adate, &meta1.atime, NULL);
 
-	exfat_read_raw(&meta2, sizeof(meta2), node->meta2_offset, ef->fd);
+	if (exfat_pread(ef->dev, &meta2, sizeof(meta2), meta2_offset) < 0)
+	{
+		exfat_error("failed to read meta2 entry on flush");
+		return -EIO;
+	}
 	if (meta2.type != EXFAT_ENTRY_FILE_INFO)
 		exfat_bug("invalid type of meta2: 0x%hhx", meta2.type);
-	meta2.size = cpu_to_le64(node->size);
+	meta2.size = meta2.valid_size = cpu_to_le64(node->size);
 	meta2.start_cluster = cpu_to_le32(node->start_cluster);
-	meta2.flag = (IS_CONTIGUOUS(*node) ?
-			EXFAT_FLAG_CONTIGUOUS : EXFAT_FLAG_FRAGMENTED);
-	/* FIXME name hash */
+	meta2.flags = EXFAT_FLAG_ALWAYS1;
+	/* empty files must not be marked as contiguous */
+	if (node->size != 0 && IS_CONTIGUOUS(*node))
+		meta2.flags |= EXFAT_FLAG_CONTIGUOUS;
+	/* name hash remains unchanged, no need to recalculate it */
+
+	meta1.checksum = exfat_calc_checksum(&meta1, &meta2, node->name);
+
+	if (exfat_pwrite(ef->dev, &meta1, sizeof(meta1), meta1_offset) < 0)
+	{
+		exfat_error("failed to write meta1 entry on flush");
+		return -EIO;
+	}
+	if (exfat_pwrite(ef->dev, &meta2, sizeof(meta2), meta2_offset) < 0)
+	{
+		exfat_error("failed to write meta2 entry on flush");
+		return -EIO;
+	}
+
+	node->flags &= ~EXFAT_ATTRIB_DIRTY;
+	return exfat_flush(ef);
+}
 
-	checksum = exfat_start_checksum(&meta1);
-	checksum = exfat_add_checksum(&meta2, checksum);
-	for (i = 1; i < meta1.continuations; i++)
+static bool erase_entry(struct exfat* ef, struct exfat_node* node)
+{
+	cluster_t cluster = node->entry_cluster;
+	off_t offset = node->entry_offset;
+	int name_entries = DIV_ROUND_UP(utf16_length(node->name), EXFAT_ENAME_MAX);
+	uint8_t entry_type;
+
+	entry_type = EXFAT_ENTRY_FILE & ~EXFAT_ENTRY_VALID;
+	if (exfat_pwrite(ef->dev, &entry_type, 1, co2o(ef, cluster, offset)) < 0)
 	{
-		struct exfat_file_name name = {EXFAT_ENTRY_FILE_NAME, 0};
-		memcpy(name.name, node->name + (i - 1) * EXFAT_ENAME_MAX,
+		exfat_error("failed to erase meta1 entry");
+		return false;
+	}
+
+	if (!next_entry(ef, node->parent, &cluster, &offset))
+		return false;
+	entry_type = EXFAT_ENTRY_FILE_INFO & ~EXFAT_ENTRY_VALID;
+	if (exfat_pwrite(ef->dev, &entry_type, 1, co2o(ef, cluster, offset)) < 0)
+	{
+		exfat_error("failed to erase meta2 entry");
+		return false;
+	}
+
+	while (name_entries--)
+	{
+		if (!next_entry(ef, node->parent, &cluster, &offset))
+			return false;
+		entry_type = EXFAT_ENTRY_FILE_NAME & ~EXFAT_ENTRY_VALID;
+		if (exfat_pwrite(ef->dev, &entry_type, 1,
+				co2o(ef, cluster, offset)) < 0)
+		{
+			exfat_error("failed to erase name entry");
+			return false;
+		}
+	}
+	return true;
+}
+
+static int shrink_directory(struct exfat* ef, struct exfat_node* dir,
+		off_t deleted_offset)
+{
+	const struct exfat_node* node;
+	const struct exfat_node* last_node;
+	uint64_t entries = 0;
+	uint64_t new_size;
+
+	if (!(dir->flags & EXFAT_ATTRIB_DIR))
+		exfat_bug("attempted to shrink a file");
+	if (!(dir->flags & EXFAT_ATTRIB_CACHED))
+		exfat_bug("attempted to shrink uncached directory");
+
+	for (last_node = node = dir->child; node; node = node->next)
+	{
+		if (deleted_offset < node->entry_offset)
+		{
+			/* there are other entries after the removed one, no way to shrink
+			   this directory */
+			return 0;
+		}
+		if (last_node->entry_offset < node->entry_offset)
+			last_node = node;
+	}
+
+	if (last_node)
+	{
+		/* offset of the last entry */
+		entries += last_node->entry_offset / sizeof(struct exfat_entry);
+		/* two subentries with meta info */
+		entries += 2;
+		/* subentries with file name */
+		entries += DIV_ROUND_UP(utf16_length(last_node->name),
+				EXFAT_ENAME_MAX);
+	}
+
+	new_size = DIV_ROUND_UP(entries * sizeof(struct exfat_entry),
+				 CLUSTER_SIZE(*ef->sb)) * CLUSTER_SIZE(*ef->sb);
+	if (new_size == 0) /* directory always has at least 1 cluster */
+		new_size = CLUSTER_SIZE(*ef->sb);
+	if (new_size == dir->size)
+		return 0;
+	return exfat_truncate(ef, dir, new_size, true);
+}
+
+static int delete(struct exfat* ef, struct exfat_node* node)
+{
+	struct exfat_node* parent = node->parent;
+	off_t deleted_offset = node->entry_offset;
+	int rc;
+
+	exfat_get_node(parent);
+	if (!erase_entry(ef, node))
+	{
+		exfat_put_node(ef, parent);
+		return -EIO;
+	}
+	exfat_update_mtime(parent);
+	tree_detach(node);
+	rc = shrink_directory(ef, parent, deleted_offset);
+	node->flags |= EXFAT_ATTRIB_UNLINKED;
+	if (rc != 0)
+	{
+		exfat_flush_node(ef, parent);
+		exfat_put_node(ef, parent);
+		return rc;
+	}
+	rc = exfat_flush_node(ef, parent);
+	exfat_put_node(ef, parent);
+	return rc;
+}
+
+int exfat_unlink(struct exfat* ef, struct exfat_node* node)
+{
+	if (node->flags & EXFAT_ATTRIB_DIR)
+		return -EISDIR;
+	return delete(ef, node);
+}
+
+int exfat_rmdir(struct exfat* ef, struct exfat_node* node)
+{
+	int rc;
+
+	if (!(node->flags & EXFAT_ATTRIB_DIR))
+		return -ENOTDIR;
+	/* check that directory is empty */
+	rc = exfat_cache_directory(ef, node);
+	if (rc != 0)
+		return rc;
+	if (node->child)
+		return -ENOTEMPTY;
+	return delete(ef, node);
+}
+
+static int grow_directory(struct exfat* ef, struct exfat_node* dir,
+		uint64_t asize, uint32_t difference)
+{
+	return exfat_truncate(ef, dir,
+			DIV_ROUND_UP(asize + difference, CLUSTER_SIZE(*ef->sb))
+				* CLUSTER_SIZE(*ef->sb), true);
+}
+
+static int find_slot(struct exfat* ef, struct exfat_node* dir,
+		cluster_t* cluster, off_t* offset, int subentries)
+{
+	struct iterator it;
+	int rc;
+	const struct exfat_entry* entry;
+	int contiguous = 0;
+
+	rc = opendir(ef, dir, &it);
+	if (rc != 0)
+		return rc;
+	for (;;)
+	{
+		if (contiguous == 0)
+		{
+			*cluster = it.cluster;
+			*offset = it.offset;
+		}
+		entry = get_entry_ptr(ef, &it);
+		if (entry->type & EXFAT_ENTRY_VALID)
+			contiguous = 0;
+		else
+			contiguous++;
+		if (contiguous == subentries)
+			break;	/* suitable slot is found */
+		if (it.offset + sizeof(struct exfat_entry) >= dir->size)
+		{
+			rc = grow_directory(ef, dir, dir->size,
+					(subentries - contiguous) * sizeof(struct exfat_entry));
+			if (rc != 0)
+			{
+				closedir(&it);
+				return rc;
+			}
+		}
+		if (!fetch_next_entry(ef, dir, &it))
+		{
+			closedir(&it);
+			return -EIO;
+		}
+	}
+	closedir(&it);
+	return 0;
+}
+
+static int write_entry(struct exfat* ef, struct exfat_node* dir,
+		const le16_t* name, cluster_t cluster, off_t offset, uint16_t attrib)
+{
+	struct exfat_node* node;
+	struct exfat_entry_meta1 meta1;
+	struct exfat_entry_meta2 meta2;
+	const size_t name_length = utf16_length(name);
+	const int name_entries = DIV_ROUND_UP(name_length, EXFAT_ENAME_MAX);
+	int i;
+
+	node = allocate_node();
+	if (node == NULL)
+		return -ENOMEM;
+	node->entry_cluster = cluster;
+	node->entry_offset = offset;
+	memcpy(node->name, name, name_length * sizeof(le16_t));
+
+	memset(&meta1, 0, sizeof(meta1));
+	meta1.type = EXFAT_ENTRY_FILE;
+	meta1.continuations = 1 + name_entries;
+	meta1.attrib = cpu_to_le16(attrib);
+	exfat_unix2exfat(time(NULL), &meta1.crdate, &meta1.crtime,
+			&meta1.crtime_cs);
+	meta1.adate = meta1.mdate = meta1.crdate;
+	meta1.atime = meta1.mtime = meta1.crtime;
+	meta1.mtime_cs = meta1.crtime_cs; /* there is no atime_cs */
+
+	memset(&meta2, 0, sizeof(meta2));
+	meta2.type = EXFAT_ENTRY_FILE_INFO;
+	meta2.flags = EXFAT_FLAG_ALWAYS1;
+	meta2.name_length = name_length;
+	meta2.name_hash = exfat_calc_name_hash(ef, node->name);
+	meta2.start_cluster = cpu_to_le32(EXFAT_CLUSTER_FREE);
+
+	meta1.checksum = exfat_calc_checksum(&meta1, &meta2, node->name);
+
+	if (exfat_pwrite(ef->dev, &meta1, sizeof(meta1),
+			co2o(ef, cluster, offset)) < 0)
+	{
+		exfat_error("failed to write meta1 entry");
+		return -EIO;
+	}
+	if (!next_entry(ef, dir, &cluster, &offset))
+		return -EIO;
+	if (exfat_pwrite(ef->dev, &meta2, sizeof(meta2),
+			co2o(ef, cluster, offset)) < 0)
+	{
+		exfat_error("failed to write meta2 entry");
+		return -EIO;
+	}
+	for (i = 0; i < name_entries; i++)
+	{
+		struct exfat_entry_name name_entry = {EXFAT_ENTRY_FILE_NAME, 0};
+		memcpy(name_entry.name, node->name + i * EXFAT_ENAME_MAX,
+				MIN(EXFAT_ENAME_MAX, EXFAT_NAME_MAX - i * EXFAT_ENAME_MAX) *
+				sizeof(le16_t));
+		if (!next_entry(ef, dir, &cluster, &offset))
+			return -EIO;
+		if (exfat_pwrite(ef->dev, &name_entry, sizeof(name_entry),
+				co2o(ef, cluster, offset)) < 0)
+		{
+			exfat_error("failed to write name entry");
+			return -EIO;
+		}
+	}
+
+	init_node_meta1(node, &meta1);
+	init_node_meta2(node, &meta2);
+
+	tree_attach(dir, node);
+	exfat_update_mtime(dir);
+	return 0;
+}
+
+static int create(struct exfat* ef, const char* path, uint16_t attrib)
+{
+	struct exfat_node* dir;
+	struct exfat_node* existing;
+	cluster_t cluster = EXFAT_CLUSTER_BAD;
+	off_t offset = -1;
+	le16_t name[EXFAT_NAME_MAX + 1];
+	int rc;
+
+	rc = exfat_split(ef, &dir, &existing, name, path);
+	if (rc != 0)
+		return rc;
+	if (existing != NULL)
+	{
+		exfat_put_node(ef, existing);
+		exfat_put_node(ef, dir);
+		return -EEXIST;
+	}
+
+	rc = find_slot(ef, dir, &cluster, &offset,
+			2 + DIV_ROUND_UP(utf16_length(name), EXFAT_ENAME_MAX));
+	if (rc != 0)
+	{
+		exfat_put_node(ef, dir);
+		return rc;
+	}
+	rc = write_entry(ef, dir, name, cluster, offset, attrib);
+	if (rc != 0)
+	{
+		exfat_put_node(ef, dir);
+		return rc;
+	}
+	rc = exfat_flush_node(ef, dir);
+	exfat_put_node(ef, dir);
+	return rc;
+}
+
+int exfat_mknod(struct exfat* ef, const char* path)
+{
+	return create(ef, path, EXFAT_ATTRIB_ARCH);
+}
+
+int exfat_mkdir(struct exfat* ef, const char* path)
+{
+	int rc;
+	struct exfat_node* node;
+
+	rc = create(ef, path, EXFAT_ATTRIB_DIR);
+	if (rc != 0)
+		return rc;
+	rc = exfat_lookup(ef, &node, path);
+	if (rc != 0)
+		return 0;
+	/* directories always have at least one cluster */
+	rc = exfat_truncate(ef, node, CLUSTER_SIZE(*ef->sb), true);
+	if (rc != 0)
+	{
+		delete(ef, node);
+		exfat_put_node(ef, node);
+		return rc;
+	}
+	rc = exfat_flush_node(ef, node);
+	if (rc != 0)
+	{
+		delete(ef, node);
+		exfat_put_node(ef, node);
+		return rc;
+	}
+	exfat_put_node(ef, node);
+	return 0;
+}
+
+static int rename_entry(struct exfat* ef, struct exfat_node* dir,
+		struct exfat_node* node, const le16_t* name, cluster_t new_cluster,
+		off_t new_offset)
+{
+	struct exfat_entry_meta1 meta1;
+	struct exfat_entry_meta2 meta2;
+	cluster_t old_cluster = node->entry_cluster;
+	off_t old_offset = node->entry_offset;
+	const size_t name_length = utf16_length(name);
+	const int name_entries = DIV_ROUND_UP(name_length, EXFAT_ENAME_MAX);
+	int i;
+
+	if (exfat_pread(ef->dev, &meta1, sizeof(meta1),
+			co2o(ef, old_cluster, old_offset)) < 0)
+	{
+		exfat_error("failed to read meta1 entry on rename");
+		return -EIO;
+	}
+	if (!next_entry(ef, node->parent, &old_cluster, &old_offset))
+		return -EIO;
+	if (exfat_pread(ef->dev, &meta2, sizeof(meta2),
+			co2o(ef, old_cluster, old_offset)) < 0)
+	{
+		exfat_error("failed to read meta2 entry on rename");
+		return -EIO;
+	}
+	meta1.continuations = 1 + name_entries;
+	meta2.name_hash = exfat_calc_name_hash(ef, name);
+	meta2.name_length = name_length;
+	meta1.checksum = exfat_calc_checksum(&meta1, &meta2, name);
+
+	if (!erase_entry(ef, node))
+		return -EIO;
+
+	node->entry_cluster = new_cluster;
+	node->entry_offset = new_offset;
+
+	if (exfat_pwrite(ef->dev, &meta1, sizeof(meta1),
+			co2o(ef, new_cluster, new_offset)) < 0)
+	{
+		exfat_error("failed to write meta1 entry on rename");
+		return -EIO;
+	}
+	if (!next_entry(ef, dir, &new_cluster, &new_offset))
+		return -EIO;
+	if (exfat_pwrite(ef->dev, &meta2, sizeof(meta2),
+			co2o(ef, new_cluster, new_offset)) < 0)
+	{
+		exfat_error("failed to write meta2 entry on rename");
+		return -EIO;
+	}
+
+	for (i = 0; i < name_entries; i++)
+	{
+		struct exfat_entry_name name_entry = {EXFAT_ENTRY_FILE_NAME, 0};
+		memcpy(name_entry.name, name + i * EXFAT_ENAME_MAX,
 				EXFAT_ENAME_MAX * sizeof(le16_t));
-		checksum = exfat_add_checksum(&name, checksum);
+		if (!next_entry(ef, dir, &new_cluster, &new_offset))
+			return -EIO;
+		if (exfat_pwrite(ef->dev, &name_entry, sizeof(name_entry),
+				co2o(ef, new_cluster, new_offset)) < 0)
+		{
+			exfat_error("failed to write name entry on rename");
+			return -EIO;
+		}
 	}
-	meta1.checksum = cpu_to_le16(checksum);
 
-	exfat_write_raw(&meta1, sizeof(meta1), node->meta1_offset, ef->fd);
-	exfat_write_raw(&meta2, sizeof(meta2), node->meta2_offset, ef->fd);
+	memcpy(node->name, name, (EXFAT_NAME_MAX + 1) * sizeof(le16_t));
+	tree_detach(node);
+	tree_attach(dir, node);
+	return 0;
+}
+
+int exfat_rename(struct exfat* ef, const char* old_path, const char* new_path)
+{
+	struct exfat_node* node;
+	struct exfat_node* existing;
+	struct exfat_node* dir;
+	cluster_t cluster = EXFAT_CLUSTER_BAD;
+	off_t offset = -1;
+	le16_t name[EXFAT_NAME_MAX + 1];
+	int rc;
+
+	rc = exfat_lookup(ef, &node, old_path);
+	if (rc != 0)
+		return rc;
+
+	rc = exfat_split(ef, &dir, &existing, name, new_path);
+	if (rc != 0)
+	{
+		exfat_put_node(ef, node);
+		return rc;
+	}
+
+	/* check that target is not a subdirectory of the source */
+	if (node->flags & EXFAT_ATTRIB_DIR)
+	{
+		struct exfat_node* p;
+
+		for (p = dir; p; p = p->parent)
+			if (node == p)
+			{
+				if (existing != NULL)
+					exfat_put_node(ef, existing);
+				exfat_put_node(ef, dir);
+				exfat_put_node(ef, node);
+				return -EINVAL;
+			}
+	}
+
+	if (existing != NULL)
+	{
+		/* remove target if it's not the same node as source */
+		if (existing != node)
+		{
+			if (existing->flags & EXFAT_ATTRIB_DIR)
+			{
+				if (node->flags & EXFAT_ATTRIB_DIR)
+					rc = exfat_rmdir(ef, existing);
+				else
+					rc = -ENOTDIR;
+			}
+			else
+			{
+				if (!(node->flags & EXFAT_ATTRIB_DIR))
+					rc = exfat_unlink(ef, existing);
+				else
+					rc = -EISDIR;
+			}
+			exfat_put_node(ef, existing);
+			if (rc != 0)
+			{
+				/* free clusters even if something went wrong; overwise they
+				   will be just lost */
+				exfat_cleanup_node(ef, existing);
+				exfat_put_node(ef, dir);
+				exfat_put_node(ef, node);
+				return rc;
+			}
+			rc = exfat_cleanup_node(ef, existing);
+			if (rc != 0)
+			{
+				exfat_put_node(ef, dir);
+				exfat_put_node(ef, node);
+				return rc;
+			}
+		}
+		else
+			exfat_put_node(ef, existing);
+	}
+
+	rc = find_slot(ef, dir, &cluster, &offset,
+			2 + DIV_ROUND_UP(utf16_length(name), EXFAT_ENAME_MAX));
+	if (rc != 0)
+	{
+		exfat_put_node(ef, dir);
+		exfat_put_node(ef, node);
+		return rc;
+	}
+	rc = rename_entry(ef, dir, node, name, cluster, offset);
+	exfat_put_node(ef, dir);
+	exfat_put_node(ef, node);
+	return rc;
+}
+
+void exfat_utimes(struct exfat_node* node, const struct timespec tv[2])
+{
+	node->atime = tv[0].tv_sec;
+	node->mtime = tv[1].tv_sec;
+	node->flags |= EXFAT_ATTRIB_DIRTY;
+}
+
+void exfat_update_atime(struct exfat_node* node)
+{
+	node->atime = time(NULL);
+	node->flags |= EXFAT_ATTRIB_DIRTY;
+}
+
+void exfat_update_mtime(struct exfat_node* node)
+{
+	node->mtime = time(NULL);
+	node->flags |= EXFAT_ATTRIB_DIRTY;
+}
+
+const char* exfat_get_label(struct exfat* ef)
+{
+	return ef->label;
+}
+
+static int find_label(struct exfat* ef, cluster_t* cluster, off_t* offset)
+{
+	struct iterator it;
+	int rc;
+
+	rc = opendir(ef, ef->root, &it);
+	if (rc != 0)
+		return rc;
+
+	for (;;)
+	{
+		if (it.offset >= ef->root->size)
+		{
+			closedir(&it);
+			return -ENOENT;
+		}
+
+		if (get_entry_ptr(ef, &it)->type == EXFAT_ENTRY_LABEL)
+		{
+			*cluster = it.cluster;
+			*offset = it.offset;
+			closedir(&it);
+			return 0;
+		}
+
+		if (!fetch_next_entry(ef, ef->root, &it))
+		{
+			closedir(&it);
+			return -EIO;
+		}
+	}
+}
+
+int exfat_set_label(struct exfat* ef, const char* label)
+{
+	le16_t label_utf16[EXFAT_ENAME_MAX + 1];
+	int rc;
+	cluster_t cluster;
+	off_t offset;
+	struct exfat_entry_label entry;
+
+	memset(label_utf16, 0, sizeof(label_utf16));
+	rc = utf8_to_utf16(label_utf16, label, EXFAT_ENAME_MAX, strlen(label));
+	if (rc != 0)
+		return rc;
+
+	rc = find_label(ef, &cluster, &offset);
+	if (rc == -ENOENT)
+		rc = find_slot(ef, ef->root, &cluster, &offset, 1);
+	if (rc != 0)
+		return rc;
+
+	entry.type = EXFAT_ENTRY_LABEL;
+	entry.length = utf16_length(label_utf16);
+	memcpy(entry.name, label_utf16, sizeof(entry.name));
+	if (entry.length == 0)
+		entry.type ^= EXFAT_ENTRY_VALID;
+
+	if (exfat_pwrite(ef->dev, &entry, sizeof(struct exfat_entry_label),
+			co2o(ef, cluster, offset)) < 0)
+	{
+		exfat_error("failed to write label entry");
+		return -EIO;
+	}
+	strcpy(ef->label, label);
+	return 0;
 }