diff mbox series

[v4,03/13] exfat: add inode operations

Message ID 20191121052618.31117-4-namjae.jeon@samsung.com (mailing list archive)
State New, archived
Headers show
Series add the latest exfat driver | expand

Commit Message

Namjae Jeon Nov. 21, 2019, 5:26 a.m. UTC
This adds the implementation of inode operations for exfat.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Sungjong Seo <sj1557.seo@samsung.com>
---
 fs/exfat/inode.c |  693 +++++++++++++++++++++
 fs/exfat/namei.c | 1488 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 2181 insertions(+)
 create mode 100644 fs/exfat/inode.c
 create mode 100644 fs/exfat/namei.c

Comments

Markus Elfring Nov. 21, 2019, 10:40 a.m. UTC | #1
> +++ b/fs/exfat/inode.c> +static int exfat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
> +		unsigned long *mapped_blocks, int *create)
> +{> +	err = exfat_map_cluster(inode, clu_offset, &cluster,
> +		*create & BMAP_ADD_CLUSTER);

I find an other indentation more appropriate.
Please align the last parameter below (or besides) the opening parenthesis.


> +	if (err) {
> +		if (err != -ENOSPC)
> +			return -EIO;
> +		return err;
> +	}

Can such source code become more succinct?

+	if (err)
+		return err != -ENOSPC ? -EIO : err;

Regards,
Markus
Greg KH Nov. 21, 2019, 11:51 a.m. UTC | #2
On Thu, Nov 21, 2019 at 11:40:28AM +0100, Markus Elfring wrote:
> > +	if (err) {
> > +		if (err != -ENOSPC)
> > +			return -EIO;
> > +		return err;
> > +	}
> 
> Can such source code become more succinct?
> 
> +	if (err)
> +		return err != -ENOSPC ? -EIO : err;

No, the original is best here.  Never use ? : if you can ever help it.
Christoph Hellwig Nov. 22, 2019, 6:33 a.m. UTC | #3
On Thu, Nov 21, 2019 at 11:40:28AM +0100, Markus Elfring wrote:
> > +	err = exfat_map_cluster(inode, clu_offset, &cluster,
> > +		*create & BMAP_ADD_CLUSTER);
> 
> I find an other indentation more appropriate.
> Please align the last parameter below (or besides) the opening parenthesis.

It is great that you find that, but I think we can leave this to
the code author.  We have plenty of example for opening brace aligned,
one or two tabs alignments in the code, and it is up to the author /
maintainer to chose one.  No need to to nitpick their choices inside the
boundaries of the normal coding space.

> > +	if (err) {
> > +		if (err != -ENOSPC)
> > +			return -EIO;
> > +		return err;
> > +	}
> 
> Can such source code become more succinct?
> 
> +	if (err)
> +		return err != -ENOSPC ? -EIO : err;

If it sufficient but a lot harder to follow.
diff mbox series

Patch

diff --git a/fs/exfat/inode.c b/fs/exfat/inode.c
new file mode 100644
index 000000000000..e1e20e74c92a
--- /dev/null
+++ b/fs/exfat/inode.c
@@ -0,0 +1,693 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
+ */
+
+#include <linux/init.h>
+#include <linux/buffer_head.h>
+#include <linux/mpage.h>
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/time.h>
+#include <linux/writeback.h>
+#include <linux/uio.h>
+#include <linux/random.h>
+#include <linux/iversion.h>
+
+#include "exfat_raw.h"
+#include "exfat_fs.h"
+
+/* 2-level option flag */
+enum {
+	BMAP_NOT_CREATE,
+	BMAP_ADD_CLUSTER,
+};
+
+static int __exfat_write_inode(struct inode *inode, int sync)
+{
+	int ret = -EIO;
+	unsigned long long on_disk_size;
+	struct exfat_timestamp tm;
+	struct exfat_dentry *ep, *ep2;
+	struct exfat_entry_set_cache *es = NULL;
+	struct super_block *sb = inode->i_sb;
+	struct exfat_sb_info *sbi = EXFAT_SB(sb);
+	struct exfat_inode_info *ei = EXFAT_I(inode);
+	unsigned char is_dir = (ei->type == TYPE_DIR) ? 1 : 0;
+	struct exfat_dir_entry info;
+
+	if (inode->i_ino == EXFAT_ROOT_INO)
+		return 0;
+
+	info.attr = exfat_make_attr(inode);
+	info.size = i_size_read(inode);
+
+	exfat_time_unix2fat(sbi, &inode->i_mtime, &info.modify_timestamp);
+	exfat_time_unix2fat(sbi, &inode->i_ctime, &info.create_timestamp);
+	exfat_time_unix2fat(sbi, &inode->i_atime, &info.access_timestamp);
+
+	/*
+	 * If the indode is already unlinked, there is no need for updating it.
+	 */
+	if (ei->dir.dir == DIR_DELETED)
+		return 0;
+
+	if (is_dir && ei->dir.dir == sbi->root_dir && ei->entry == -1)
+		return 0;
+
+	exfat_set_vol_flags(sb, VOL_DIRTY);
+
+	/* get the directory entry of given file or directory */
+	es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES,
+		&ep);
+	if (!es)
+		return -EIO;
+	ep2 = ep + 1;
+
+	ep->file_attr = cpu_to_le16(info.attr);
+
+	/* set FILE_INFO structure using the acquired struct exfat_dentry */
+	tm.sec  = info.create_timestamp.second;
+	tm.min  = info.create_timestamp.minute;
+	tm.hour = info.create_timestamp.hour;
+	tm.day  = info.create_timestamp.day;
+	tm.mon  = info.create_timestamp.month;
+	tm.year = info.create_timestamp.year;
+	exfat_set_entry_time(ep, &tm, TM_CREATE);
+
+	tm.sec  = info.modify_timestamp.second;
+	tm.min  = info.modify_timestamp.minute;
+	tm.hour = info.modify_timestamp.hour;
+	tm.day  = info.modify_timestamp.day;
+	tm.mon  = info.modify_timestamp.month;
+	tm.year = info.modify_timestamp.year;
+	exfat_set_entry_time(ep, &tm, TM_MODIFY);
+
+	/* File size should be zero if there is no cluster allocated */
+	on_disk_size = info.size;
+
+	if (ei->start_clu == EOF_CLUSTER)
+		on_disk_size = 0;
+
+	ep2->stream_valid_size = cpu_to_le64(on_disk_size);
+	ep2->stream_size = ep2->stream_valid_size;
+
+	ret = exfat_update_dir_chksum_with_entry_set(sb, es, sync);
+	kfree(es);
+	return ret;
+}
+
+int exfat_write_inode(struct inode *inode, struct writeback_control *wbc)
+{
+	int ret;
+
+	mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
+	ret = __exfat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
+	mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
+
+	return ret;
+}
+
+void exfat_sync_inode(struct inode *inode)
+{
+	lockdep_assert_held(&EXFAT_SB(inode->i_sb)->s_lock);
+	__exfat_write_inode(inode, 1);
+}
+
+/*
+ * Input: inode, (logical) clu_offset, target allocation area
+ * Output: errcode, cluster number
+ * *clu = (~0), if it's unable to allocate a new cluster
+ */
+static int exfat_map_cluster(struct inode *inode, unsigned int clu_offset,
+		unsigned int *clu, int create)
+{
+	int ret, modified = false;
+	unsigned int last_clu;
+	struct exfat_chain new_clu;
+	struct exfat_dentry *ep;
+	struct exfat_entry_set_cache *es = NULL;
+	struct super_block *sb = inode->i_sb;
+	struct exfat_sb_info *sbi = EXFAT_SB(sb);
+	struct exfat_inode_info *ei = EXFAT_I(inode);
+	unsigned int local_clu_offset = clu_offset;
+	unsigned int num_to_be_allocated = 0, num_clusters = 0;
+
+	ei->rwoffset = EXFAT_CLU_TO_B(clu_offset, sbi);
+
+	if (EXFAT_I(inode)->i_size_ondisk > 0)
+		num_clusters =
+			EXFAT_B_TO_CLU_ROUND_UP(EXFAT_I(inode)->i_size_ondisk,
+			sbi);
+
+	if (clu_offset >= num_clusters)
+		num_to_be_allocated = clu_offset - num_clusters + 1;
+
+	if (!create && (num_to_be_allocated > 0)) {
+		*clu = EOF_CLUSTER;
+		return 0;
+	}
+
+	*clu = last_clu = ei->start_clu;
+
+	if (ei->flags == ALLOC_NO_FAT_CHAIN) {
+		if (clu_offset > 0 && *clu != EOF_CLUSTER) {
+			last_clu += clu_offset - 1;
+
+			if (clu_offset == num_clusters)
+				*clu = EOF_CLUSTER;
+			else
+				*clu += clu_offset;
+		}
+	} else if (ei->type == TYPE_FILE) {
+		unsigned int fclus = 0;
+		int err = exfat_get_cluster(inode, clu_offset,
+				&fclus, clu, &last_clu, 1);
+		if (err)
+			return -EIO;
+
+		clu_offset -= fclus;
+	} else {
+		/* hint information */
+		if (clu_offset > 0 && ei->hint_bmap.off != EOF_CLUSTER &&
+		    ei->hint_bmap.off > 0 && clu_offset >= ei->hint_bmap.off) {
+			clu_offset -= ei->hint_bmap.off;
+			/* hint_bmap.clu should be valid */
+			WARN_ON(ei->hint_bmap.clu < 2);
+			*clu = ei->hint_bmap.clu;
+		}
+
+		while (clu_offset > 0 && *clu != EOF_CLUSTER) {
+			last_clu = *clu;
+			if (exfat_get_next_cluster(sb, clu))
+				return -EIO;
+			clu_offset--;
+		}
+	}
+
+	if (*clu == EOF_CLUSTER) {
+		exfat_set_vol_flags(sb, VOL_DIRTY);
+
+		new_clu.dir = (last_clu == EOF_CLUSTER) ?
+				EOF_CLUSTER : last_clu + 1;
+		new_clu.size = 0;
+		new_clu.flags = ei->flags;
+
+		/* allocate a cluster */
+		if (num_to_be_allocated < 1) {
+			/* Broken FAT (i_sze > allocated FAT) */
+			exfat_fs_error(sb, "broken FAT chain.");
+			return -EIO;
+		}
+
+		ret = exfat_alloc_cluster(inode, num_to_be_allocated, &new_clu);
+		if (ret)
+			return ret;
+
+		if (new_clu.dir == EOF_CLUSTER || new_clu.dir == FREE_CLUSTER) {
+			exfat_fs_error(sb,
+				"bogus cluster new allocated (last_clu : %u, new_clu : %u)",
+				last_clu, new_clu.dir);
+			return -EIO;
+		}
+
+		/* append to the FAT chain */
+		if (last_clu == EOF_CLUSTER) {
+			if (new_clu.flags == ALLOC_FAT_CHAIN)
+				ei->flags = ALLOC_FAT_CHAIN;
+			ei->start_clu = new_clu.dir;
+			modified = true;
+		} else {
+			if (new_clu.flags != ei->flags) {
+				/* no-fat-chain bit is disabled,
+				 * so fat-chain should be synced with
+				 * alloc-bitmap
+				 */
+				exfat_chain_cont_cluster(sb, ei->start_clu,
+					num_clusters);
+				ei->flags = ALLOC_FAT_CHAIN;
+				modified = true;
+			}
+			if (new_clu.flags == ALLOC_FAT_CHAIN)
+				if (exfat_ent_set(sb, last_clu, new_clu.dir))
+					return -EIO;
+		}
+
+		num_clusters += num_to_be_allocated;
+		*clu = new_clu.dir;
+
+		if (ei->dir.dir != DIR_DELETED) {
+			es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry,
+				ES_ALL_ENTRIES, &ep);
+			if (!es)
+				return -EIO;
+			/* get stream entry */
+			ep++;
+
+			/* update directory entry */
+			if (modified) {
+				if (ep->stream_flags != ei->flags)
+					ep->stream_flags = ei->flags;
+
+				if (le32_to_cpu(ep->stream_start_clu) !=
+						ei->start_clu)
+					ep->stream_start_clu =
+						cpu_to_le32(ei->start_clu);
+
+				ep->stream_valid_size =
+					cpu_to_le64(i_size_read(inode));
+				ep->stream_size = ep->stream_valid_size;
+			}
+
+			if (exfat_update_dir_chksum_with_entry_set(sb, es,
+			    inode_needs_sync(inode)))
+				return -EIO;
+			kfree(es);
+
+		} /* end of if != DIR_DELETED */
+
+		inode->i_blocks +=
+			num_to_be_allocated << sbi->sect_per_clus_bits;
+
+		/*
+		 * Move *clu pointer along FAT chains (hole care) because the
+		 * caller of this function expect *clu to be the last cluster.
+		 * This only works when num_to_be_allocated >= 2,
+		 * *clu = (the first cluster of the allocated chain) =>
+		 * (the last cluster of ...)
+		 */
+		if (ei->flags == ALLOC_NO_FAT_CHAIN) {
+			*clu += num_to_be_allocated - 1;
+		} else {
+			while (num_to_be_allocated > 1) {
+				if (exfat_get_next_cluster(sb, clu))
+					return -EIO;
+				num_to_be_allocated--;
+			}
+		}
+
+	}
+
+	/* hint information */
+	ei->hint_bmap.off = local_clu_offset;
+	ei->hint_bmap.clu = *clu;
+
+	return 0;
+}
+
+static int exfat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
+		unsigned long *mapped_blocks, int *create)
+{
+	struct super_block *sb = inode->i_sb;
+	struct exfat_sb_info *sbi = EXFAT_SB(sb);
+	sector_t last_block;
+	unsigned int cluster, clu_offset, sec_offset;
+	int err = 0;
+
+	*phys = 0;
+	*mapped_blocks = 0;
+
+	last_block = EXFAT_B_TO_BLK_ROUND_UP(i_size_read(inode), sb);
+	if (sector >= last_block && *create == BMAP_NOT_CREATE)
+		return 0;
+
+	/* Is this block already allocated? */
+	clu_offset = sector >> sbi->sect_per_clus_bits;  /* cluster offset */
+
+	err = exfat_map_cluster(inode, clu_offset, &cluster,
+		*create & BMAP_ADD_CLUSTER);
+	if (err) {
+		if (err != -ENOSPC)
+			return -EIO;
+		return err;
+	}
+
+	if (cluster != EOF_CLUSTER) {
+		/* sector offset in cluster */
+		sec_offset = sector & (sbi->sect_per_clus - 1);
+
+		*phys = exfat_cluster_to_sector(sbi, cluster) + sec_offset;
+		*mapped_blocks = sbi->sect_per_clus - sec_offset;
+	}
+
+	if (sector < last_block)
+		*create = BMAP_NOT_CREATE;
+	return 0;
+}
+
+static int exfat_get_block(struct inode *inode, sector_t iblock,
+		struct buffer_head *bh_result, int create)
+{
+	struct super_block *sb = inode->i_sb;
+	unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
+	int err = 0;
+	unsigned long mapped_blocks;
+	sector_t phys;
+	loff_t pos;
+	int bmap_create = create ? BMAP_ADD_CLUSTER : BMAP_NOT_CREATE;
+
+	mutex_lock(&EXFAT_SB(sb)->s_lock);
+	err = exfat_bmap(inode, iblock, &phys, &mapped_blocks, &bmap_create);
+	if (err) {
+		if (err != -ENOSPC)
+			exfat_fs_error_ratelimit(sb,
+				"failed to bmap (inode : %p iblock : %llu, err : %d)",
+				inode, (unsigned long long)iblock, err);
+		goto unlock_ret;
+	}
+
+	if (phys) {
+		max_blocks = min(mapped_blocks, max_blocks);
+
+		/* Treat newly added block / cluster */
+		if (bmap_create || buffer_delay(bh_result)) {
+			/* Update i_size_ondisk */
+			pos = EXFAT_BLK_TO_B((iblock + 1), sb);
+			if (EXFAT_I(inode)->i_size_ondisk < pos)
+				EXFAT_I(inode)->i_size_ondisk = pos;
+
+			if (bmap_create) {
+				if (buffer_delay(bh_result) &&
+				    pos > EXFAT_I(inode)->i_size_aligned) {
+					exfat_fs_error(sb,
+						"requested for bmap out of range(pos : (%llu) > i_size_aligned(%llu)\n",
+						pos,
+						EXFAT_I(inode)->i_size_aligned);
+					err = -EIO;
+					goto unlock_ret;
+				}
+				set_buffer_new(bh_result);
+
+				/*
+				 * adjust i_size_aligned if i_size_ondisk is
+				 * bigger than it. (i.e. non-DA)
+				 */
+				if (EXFAT_I(inode)->i_size_ondisk >
+				    EXFAT_I(inode)->i_size_aligned) {
+					EXFAT_I(inode)->i_size_aligned =
+						EXFAT_I(inode)->i_size_ondisk;
+				}
+			}
+
+			if (buffer_delay(bh_result))
+				clear_buffer_delay(bh_result);
+		}
+		map_bh(bh_result, sb, phys);
+	}
+
+	bh_result->b_size = EXFAT_BLK_TO_B(max_blocks, sb);
+unlock_ret:
+	mutex_unlock(&EXFAT_SB(sb)->s_lock);
+	return err;
+}
+
+static int exfat_readpage(struct file *file, struct page *page)
+{
+	return mpage_readpage(page, exfat_get_block);
+}
+
+static int exfat_readpages(struct file *file, struct address_space *mapping,
+		struct list_head *pages, unsigned int nr_pages)
+{
+	return mpage_readpages(mapping, pages, nr_pages, exfat_get_block);
+}
+
+static int exfat_writepage(struct page *page, struct writeback_control *wbc)
+{
+	return block_write_full_page(page, exfat_get_block, wbc);
+}
+
+static int exfat_writepages(struct address_space *mapping,
+		struct writeback_control *wbc)
+{
+	return mpage_writepages(mapping, wbc, exfat_get_block);
+}
+
+static void exfat_write_failed(struct address_space *mapping, loff_t to)
+{
+	struct inode *inode = mapping->host;
+
+	if (to > i_size_read(inode)) {
+		truncate_pagecache(inode, i_size_read(inode));
+		exfat_truncate(inode, EXFAT_I(inode)->i_size_aligned);
+	}
+}
+
+static int exfat_write_begin(struct file *file, struct address_space *mapping,
+		loff_t pos, unsigned int len, unsigned int flags,
+		struct page **pagep, void **fsdata)
+{
+	int ret;
+
+	*pagep = NULL;
+	ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
+			       exfat_get_block,
+			       &EXFAT_I(mapping->host)->i_size_ondisk);
+
+	if (ret < 0)
+		exfat_write_failed(mapping, pos+len);
+
+	return ret;
+}
+
+static int exfat_write_end(struct file *file, struct address_space *mapping,
+		loff_t pos, unsigned int len, unsigned int copied,
+		struct page *pagep, void *fsdata)
+{
+	struct inode *inode = mapping->host;
+	struct exfat_inode_info *ei = EXFAT_I(inode);
+	int err;
+
+	err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
+
+	if (EXFAT_I(inode)->i_size_aligned < i_size_read(inode)) {
+		exfat_fs_error(inode->i_sb,
+			"invalid size(size(%llu) > aligned(%llu)\n",
+			i_size_read(inode), EXFAT_I(inode)->i_size_aligned);
+		return -EIO;
+	}
+
+	if (err < len)
+		exfat_write_failed(mapping, pos+len);
+
+	if (!(err < 0) && !(ei->attr & ATTR_ARCHIVE)) {
+		inode->i_mtime = inode->i_ctime = current_time(inode);
+		ei->attr |= ATTR_ARCHIVE;
+		mark_inode_dirty(inode);
+	}
+
+	return err;
+}
+
+static ssize_t exfat_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
+{
+	struct address_space *mapping = iocb->ki_filp->f_mapping;
+	struct inode *inode = mapping->host;
+	loff_t size = iocb->ki_pos + iov_iter_count(iter);
+	int rw = iov_iter_rw(iter);
+	ssize_t ret;
+
+	if (rw == WRITE) {
+		/*
+		 * FIXME: blockdev_direct_IO() doesn't use ->write_begin(),
+		 * so we need to update the ->i_size_aligned to block boundary.
+		 *
+		 * But we must fill the remaining area or hole by nul for
+		 * updating ->i_size_aligned
+		 *
+		 * Return 0, and fallback to normal buffered write.
+		 */
+		if (EXFAT_I(inode)->i_size_aligned < size)
+			return 0;
+	}
+
+	/*
+	 * Need to use the DIO_LOCKING for avoiding the race
+	 * condition of exfat_get_block() and ->truncate().
+	 */
+	ret = blockdev_direct_IO(iocb, inode, iter, exfat_get_block);
+	if (ret < 0 && (rw & WRITE))
+		exfat_write_failed(mapping, size);
+	return ret;
+}
+
+static sector_t exfat_aop_bmap(struct address_space *mapping, sector_t block)
+{
+	sector_t blocknr;
+
+	/* exfat_get_cluster() assumes the requested blocknr isn't truncated. */
+	down_read(&EXFAT_I(mapping->host)->truncate_lock);
+	blocknr = generic_block_bmap(mapping, block, exfat_get_block);
+	up_read(&EXFAT_I(mapping->host)->truncate_lock);
+	return blocknr;
+}
+
+static const struct address_space_operations exfat_aops = {
+	.readpage	= exfat_readpage,
+	.readpages	= exfat_readpages,
+	.writepage	= exfat_writepage,
+	.writepages	= exfat_writepages,
+	.write_begin	= exfat_write_begin,
+	.write_end	= exfat_write_end,
+	.direct_IO	= exfat_direct_IO,
+	.bmap		= exfat_aop_bmap
+};
+
+static inline unsigned long exfat_hash(loff_t i_pos)
+{
+	return hash_32(i_pos, EXFAT_HASH_BITS);
+}
+
+void exfat_hash_inode(struct inode *inode, loff_t i_pos)
+{
+	struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
+	struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
+
+	spin_lock(&sbi->inode_hash_lock);
+	EXFAT_I(inode)->i_pos = i_pos;
+	hlist_add_head(&EXFAT_I(inode)->i_hash_fat, head);
+	spin_unlock(&sbi->inode_hash_lock);
+}
+
+void exfat_unhash_inode(struct inode *inode)
+{
+	struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
+
+	spin_lock(&sbi->inode_hash_lock);
+	hlist_del_init(&EXFAT_I(inode)->i_hash_fat);
+	EXFAT_I(inode)->i_pos = 0;
+	spin_unlock(&sbi->inode_hash_lock);
+}
+
+struct inode *exfat_iget(struct super_block *sb, loff_t i_pos)
+{
+	struct exfat_sb_info *sbi = EXFAT_SB(sb);
+	struct exfat_inode_info *info;
+	struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
+	struct inode *inode = NULL;
+
+	spin_lock(&sbi->inode_hash_lock);
+	hlist_for_each_entry(info, head, i_hash_fat) {
+		WARN_ON(info->vfs_inode.i_sb != sb);
+
+		if (i_pos != info->i_pos)
+			continue;
+		inode = igrab(&info->vfs_inode);
+		if (inode)
+			break;
+	}
+	spin_unlock(&sbi->inode_hash_lock);
+	return inode;
+}
+
+/* doesn't deal with root inode */
+static int exfat_fill_inode(struct inode *inode, struct exfat_dir_entry *info)
+{
+	struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
+	struct exfat_inode_info *ei = EXFAT_I(inode);
+	loff_t size = info->size;
+
+	memcpy(&ei->dir, &info->dir, sizeof(struct exfat_chain));
+	ei->entry = info->entry;
+	ei->attr = info->attr;
+	ei->start_clu = info->start_clu;
+	ei->flags = info->flags;
+	ei->type = info->type;
+
+	ei->version = 0;
+	ei->hint_stat.eidx = 0;
+	ei->hint_stat.clu = info->start_clu;
+	ei->hint_femp.eidx = EXFAT_HINT_NONE;
+	ei->rwoffset = 0;
+	ei->hint_bmap.off = EOF_CLUSTER;
+	ei->i_pos = 0;
+
+	inode->i_uid = sbi->options.fs_uid;
+	inode->i_gid = sbi->options.fs_gid;
+	inode_inc_iversion(inode);
+	inode->i_generation = prandom_u32();
+
+	if (info->attr & ATTR_SUBDIR) { /* directory */
+		inode->i_generation &= ~1;
+		inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
+		inode->i_op = &exfat_dir_inode_operations;
+		inode->i_fop = &exfat_dir_operations;
+		set_nlink(inode, info->num_subdirs);
+	} else { /* regular file */
+		inode->i_generation |= 1;
+		inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
+		inode->i_op = &exfat_file_inode_operations;
+		inode->i_fop = &exfat_file_operations;
+		inode->i_mapping->a_ops = &exfat_aops;
+		inode->i_mapping->nrpages = 0;
+	}
+
+	i_size_write(inode, size);
+
+	/* ondisk and aligned size should be aligned with block size */
+	if (size & (inode->i_sb->s_blocksize - 1)) {
+		size |= (inode->i_sb->s_blocksize - 1);
+		size++;
+	}
+
+	ei->i_size_aligned = size;
+	ei->i_size_ondisk = size;
+
+	exfat_save_attr(inode, info->attr);
+
+	inode->i_blocks = ((i_size_read(inode) + (sbi->cluster_size - 1)) &
+		~(sbi->cluster_size - 1)) >> inode->i_blkbits;
+
+	exfat_time_fat2unix(sbi, &inode->i_mtime, &info->modify_timestamp);
+	exfat_time_fat2unix(sbi, &inode->i_ctime, &info->create_timestamp);
+	exfat_time_fat2unix(sbi, &inode->i_atime, &info->access_timestamp);
+
+	exfat_cache_init_inode(inode);
+
+	return 0;
+}
+
+struct inode *exfat_build_inode(struct super_block *sb,
+		struct exfat_dir_entry *info, loff_t i_pos)
+{
+	struct inode *inode;
+	int err;
+
+	inode = exfat_iget(sb, i_pos);
+	if (inode)
+		goto out;
+	inode = new_inode(sb);
+	if (!inode) {
+		inode = ERR_PTR(-ENOMEM);
+		goto out;
+	}
+	inode->i_ino = iunique(sb, EXFAT_ROOT_INO);
+	inode_set_iversion(inode, 1);
+	err = exfat_fill_inode(inode, info);
+	if (err) {
+		iput(inode);
+		inode = ERR_PTR(err);
+		goto out;
+	}
+	exfat_hash_inode(inode, i_pos);
+	insert_inode_hash(inode);
+out:
+	return inode;
+}
+
+void exfat_evict_inode(struct inode *inode)
+{
+	truncate_inode_pages(&inode->i_data, 0);
+
+	if (!inode->i_nlink) {
+		i_size_write(inode, 0);
+		mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
+		__exfat_truncate(inode, 0);
+		mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
+	}
+
+	invalidate_inode_buffers(inode);
+	clear_inode(inode);
+	exfat_cache_inval_inode(inode);
+	exfat_unhash_inode(inode);
+}
diff --git a/fs/exfat/namei.c b/fs/exfat/namei.c
new file mode 100644
index 000000000000..e51ca0dd9e04
--- /dev/null
+++ b/fs/exfat/namei.c
@@ -0,0 +1,1488 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
+ */
+
+#include <linux/iversion.h>
+#include <linux/namei.h>
+#include <linux/slab.h>
+#include <linux/buffer_head.h>
+#include <linux/nls.h>
+
+#include "exfat_raw.h"
+#include "exfat_fs.h"
+
+static inline unsigned long exfat_d_version(struct dentry *dentry)
+{
+	return (unsigned long) dentry->d_fsdata;
+}
+
+static inline void exfat_d_version_set(struct dentry *dentry,
+		unsigned long version)
+{
+	dentry->d_fsdata = (void *) version;
+}
+
+/*
+ * If new entry was created in the parent, it could create the 8.3
+ * alias (the shortname of logname).  So, the parent may have the
+ * negative-dentry which matches the created 8.3 alias.
+ *
+ * If it happened, the negative dentry isn't actually negative
+ * anymore.  So, drop it.
+ */
+static int __exfat_revalidate_common(struct dentry *dentry)
+{
+	int ret = 1;
+
+	spin_lock(&dentry->d_lock);
+	if (!inode_eq_iversion(d_inode(dentry->d_parent),
+			exfat_d_version(dentry)))
+		ret = 0;
+	spin_unlock(&dentry->d_lock);
+	return ret;
+}
+
+static int __exfat_revalidate(struct dentry *dentry)
+{
+	/* This is not negative dentry. Always valid. */
+	if (d_really_is_positive(dentry))
+		return 1;
+	return __exfat_revalidate_common(dentry);
+}
+
+static int __exfat_revalidate_ci(struct dentry *dentry, unsigned int flags)
+{
+	/*
+	 * This is not negative dentry. Always valid.
+	 *
+	 * Note, rename() to existing directory entry will have ->d_inode,
+	 * and will use existing name which isn't specified name by user.
+	 *
+	 * We may be able to drop this positive dentry here. But dropping
+	 * positive dentry isn't good idea. So it's unsupported like
+	 * rename("filename", "FILENAME") for now.
+	 */
+	if (d_really_is_positive(dentry))
+		return 1;
+	/*
+	 * Drop the negative dentry, in order to make sure to use the
+	 * case sensitive name which is specified by user if this is
+	 * for creation.
+	 */
+	if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
+		return 0;
+	return __exfat_revalidate_common(dentry);
+}
+
+
+/* returns the length of a struct qstr, ignoring trailing dots */
+static unsigned int __exfat_striptail_len(unsigned int len, const char *name)
+{
+	while (len && name[len - 1] == '.')
+		len--;
+	return len;
+}
+
+static unsigned int exfat_striptail_len(const struct qstr *qstr)
+{
+	return __exfat_striptail_len(qstr->len, qstr->name);
+}
+
+static inline unsigned int __exfat_full_name_hash(const struct dentry *dentry,
+		const char *name, unsigned int len)
+{
+	return full_name_hash(dentry, name, len);
+}
+
+static inline unsigned long __exfat_init_name_hash(const struct dentry *dentry)
+{
+	return init_name_hash(dentry);
+}
+
+/*
+ * Compute the hash for the exfat name corresponding to the dentry.
+ * Note: if the name is invalid, we leave the hash code unchanged so
+ * that the existing dentry can be used. The exfat fs routines will
+ * return ENOENT or EINVAL as appropriate.
+ */
+static int exfat_d_hash(const struct dentry *dentry, struct qstr *qstr)
+{
+	unsigned int len = exfat_striptail_len(qstr);
+
+	qstr->hash = __exfat_full_name_hash(dentry, qstr->name, len);
+	return 0;
+}
+
+/*
+ * Compute the hash for the exfat name corresponding to the dentry.
+ * Note: if the name is invalid, we leave the hash code unchanged so
+ * that the existing dentry can be used. The exfat fs routines will
+ * return ENOENT or EINVAL as appropriate.
+ */
+static int exfat_d_hashi(const struct dentry *dentry, struct qstr *qstr)
+{
+	struct nls_table *t = EXFAT_SB(dentry->d_sb)->nls_io;
+	const unsigned char *name;
+	unsigned int len;
+	unsigned long hash;
+
+	name = qstr->name;
+	len = exfat_striptail_len(qstr);
+
+	hash = __exfat_init_name_hash(dentry);
+	while (len--)
+		hash = partial_name_hash(nls_tolower(t, *name++), hash);
+	qstr->hash = end_name_hash(hash);
+
+	return 0;
+}
+
+/*
+ * Case sensitive compare of two exfat names.
+ */
+static int exfat_cmp(const struct dentry *dentry, unsigned int len,
+		const char *str, const struct qstr *name)
+{
+	unsigned int alen, blen;
+
+	/* A filename cannot end in '.' or we treat it like it has none */
+	alen = exfat_striptail_len(name);
+	blen = __exfat_striptail_len(len, str);
+	if (alen == blen) {
+		if (strncmp(name->name, str, alen) == 0)
+			return 0;
+	}
+	return 1;
+}
+
+/*
+ * Case insensitive compare of two exfat names.
+ */
+static int exfat_cmpi(const struct dentry *dentry, unsigned int len,
+		const char *str, const struct qstr *name)
+{
+	struct nls_table *t = EXFAT_SB(dentry->d_sb)->nls_io;
+	unsigned int alen, blen;
+
+	/* A filename cannot end in '.' or we treat it like it has none */
+	alen = exfat_striptail_len(name);
+	blen = __exfat_striptail_len(len, str);
+	if (alen == blen) {
+		if (nls_strnicmp(t, name->name, str, alen) == 0)
+			return 0;
+	}
+	return 1;
+}
+
+static int exfat_revalidate(struct dentry *dentry, unsigned int flags)
+{
+	if (flags & LOOKUP_RCU)
+		return -ECHILD;
+
+	return __exfat_revalidate(dentry);
+}
+
+static int exfat_revalidate_ci(struct dentry *dentry, unsigned int flags)
+{
+	if (flags & LOOKUP_RCU)
+		return -ECHILD;
+
+	return __exfat_revalidate_ci(dentry, flags);
+}
+
+const struct dentry_operations exfat_dentry_ops = {
+	.d_revalidate	= exfat_revalidate,
+	.d_hash		= exfat_d_hash,
+	.d_compare	= exfat_cmp,
+};
+
+const struct dentry_operations exfat_ci_dentry_ops = {
+	.d_revalidate	= exfat_revalidate_ci,
+	.d_hash		= exfat_d_hashi,
+	.d_compare	= exfat_cmpi,
+};
+
+/* used only in search empty_slot() */
+#define CNT_UNUSED_NOHIT        (-1)
+#define CNT_UNUSED_HIT          (-2)
+/* search EMPTY CONTINUOUS "num_entries" entries */
+static int exfat_search_empty_slot(struct super_block *sb,
+		struct exfat_hint_femp *hint_femp, struct exfat_chain *p_dir,
+		int num_entries)
+{
+	int i, dentry, num_empty = 0, ret = -ENOSPC;
+	int dentries_per_clu;
+	unsigned int type;
+	struct exfat_chain *clu;
+	struct exfat_dentry *ep;
+	struct exfat_sb_info *sbi = EXFAT_SB(sb);
+	struct buffer_head *bh;
+
+	dentries_per_clu = sbi->dentries_per_clu;
+
+	if (hint_femp->eidx != EXFAT_HINT_NONE) {
+		dentry = hint_femp->eidx;
+		if (num_entries <= hint_femp->count) {
+			hint_femp->eidx = EXFAT_HINT_NONE;
+			return dentry;
+		}
+
+		clu = exfat_chain_dup(&hint_femp->cur);
+	} else {
+		clu = exfat_chain_dup(p_dir);
+		dentry = 0;
+	}
+
+	while (clu->dir != EOF_CLUSTER) {
+		i = dentry & (dentries_per_clu - 1);
+
+		for (; i < dentries_per_clu; i++, dentry++) {
+			ep = exfat_get_dentry(sb, clu, i, &bh, NULL);
+			if (!ep) {
+				ret = -EIO;
+				goto free_clu;
+			}
+			type = exfat_get_entry_type(ep);
+			brelse(bh);
+
+			if (type == TYPE_UNUSED || type == TYPE_DELETED) {
+				num_empty++;
+				if (hint_femp->eidx == EXFAT_HINT_NONE) {
+					hint_femp->eidx = dentry;
+					hint_femp->count = CNT_UNUSED_NOHIT;
+					exfat_chain_set(&hint_femp->cur,
+						clu->dir, clu->size,
+						clu->flags);
+				}
+
+				if (type == TYPE_UNUSED &&
+				    hint_femp->count != CNT_UNUSED_HIT)
+					hint_femp->count = CNT_UNUSED_HIT;
+			} else {
+				if (hint_femp->eidx != EXFAT_HINT_NONE &&
+				    hint_femp->count == CNT_UNUSED_HIT) {
+					/* unused empty group means
+					 * an empty group which includes
+					 * unused dentry
+					 */
+					exfat_fs_error(sb,
+						"found bogus dentry(%d) beyond unused empty group(%d) (start_clu : %u, cur_clu : %u)",
+						dentry, hint_femp->eidx,
+						p_dir->dir, clu->dir);
+					ret = -EIO;
+					goto free_clu;
+				}
+
+				num_empty = 0;
+				hint_femp->eidx = EXFAT_HINT_NONE;
+			}
+
+			if (num_empty >= num_entries) {
+				/* found and invalidate hint_femp */
+				hint_femp->eidx = EXFAT_HINT_NONE;
+				ret = (dentry - (num_entries - 1));
+				goto free_clu;
+			}
+		}
+
+		if (clu->flags == ALLOC_NO_FAT_CHAIN) {
+			if (--clu->size > 0)
+				clu->dir++;
+			else
+				clu->dir = EOF_CLUSTER;
+		} else {
+			if (exfat_get_next_cluster(sb, &clu->dir)) {
+				ret = -EIO;
+				goto free_clu;
+			}
+		}
+	}
+free_clu:
+	kfree(clu);
+	return ret;
+}
+
+static int exfat_check_max_dentries(struct inode *inode)
+{
+	if (EXFAT_B_TO_DEN(i_size_read(inode)) >= MAX_EXFAT_DENTRIES) {
+		/*
+		 * exFAT spec allows a dir to grow upto 8388608(256MB)
+		 * dentries
+		 */
+		return -ENOSPC;
+	}
+	return 0;
+}
+
+/* find empty directory entry.
+ * if there isn't any empty slot, expand cluster chain.
+ */
+int exfat_find_empty_entry(struct inode *inode, struct exfat_chain *p_dir,
+		int num_entries)
+{
+	int dentry;
+	unsigned int ret, last_clu;
+	sector_t sector;
+	loff_t size = 0;
+	struct exfat_chain clu;
+	struct exfat_dentry *ep = NULL;
+	struct super_block *sb = inode->i_sb;
+	struct exfat_sb_info *sbi = EXFAT_SB(sb);
+	struct exfat_inode_info *ei = EXFAT_I(inode);
+	struct exfat_hint_femp hint_femp;
+
+	hint_femp.eidx = EXFAT_HINT_NONE;
+
+	if (ei->hint_femp.eidx != EXFAT_HINT_NONE) {
+		memcpy(&hint_femp, &ei->hint_femp,
+				sizeof(struct exfat_hint_femp));
+		ei->hint_femp.eidx = EXFAT_HINT_NONE;
+	}
+
+	while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir,
+					num_entries)) < 0) {
+		if (dentry == -EIO)
+			break;
+
+		if (exfat_check_max_dentries(inode))
+			return -ENOSPC;
+
+		/* we trust p_dir->size regardless of FAT type */
+		if (exfat_find_last_cluster(sb, p_dir, &last_clu))
+			return -EIO;
+
+		/*
+		 * Allocate new cluster to this directory
+		 */
+		exfat_chain_set(&clu, last_clu + 1, 0, p_dir->flags);
+
+		/* allocate a cluster */
+		ret = exfat_alloc_cluster(inode, 1, &clu);
+		if (ret)
+			return ret;
+
+		if (exfat_zeroed_cluster(inode, clu.dir))
+			return -EIO;
+
+		/* append to the FAT chain */
+		if (clu.flags != p_dir->flags) {
+			/* no-fat-chain bit is disabled,
+			 * so fat-chain should be synced with alloc-bitmap
+			 */
+			exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size);
+			p_dir->flags = ALLOC_FAT_CHAIN;
+			hint_femp.cur.flags = ALLOC_FAT_CHAIN;
+		}
+
+		if (clu.flags == ALLOC_FAT_CHAIN)
+			if (exfat_ent_set(sb, last_clu, clu.dir))
+				return -EIO;
+
+		if (hint_femp.eidx == EXFAT_HINT_NONE) {
+			/* the special case that new dentry
+			 * should be allocated from the start of new cluster
+			 */
+			hint_femp.eidx = EXFAT_B_TO_DEN_IDX(p_dir->size, sbi);
+			hint_femp.count = sbi->dentries_per_clu;
+
+			exfat_chain_set(&hint_femp.cur, clu.dir, 0, clu.flags);
+		}
+		hint_femp.cur.size++;
+		p_dir->size++;
+		size = EXFAT_CLU_TO_B(p_dir->size, sbi);
+
+		/* update the directory entry */
+		if (p_dir->dir != sbi->root_dir) {
+			struct buffer_head *bh;
+
+			ep = exfat_get_dentry(sb,
+				&(ei->dir), ei->entry + 1, &bh, &sector);
+			if (!ep)
+				return -EIO;
+
+			ep->stream_valid_size = cpu_to_le64(size);
+			ep->stream_size = ep->stream_valid_size;
+			ep->stream_flags = p_dir->flags;
+			exfat_update_bh(sb, bh, IS_DIRSYNC(inode));
+			brelse(bh);
+			if (update_dir_chksum(inode, &(ei->dir), ei->entry))
+				return -EIO;
+		}
+
+		/* directory inode should be updated in here */
+		i_size_write(inode, size);
+		EXFAT_I(inode)->i_size_ondisk += sbi->cluster_size;
+		EXFAT_I(inode)->i_size_aligned += sbi->cluster_size;
+		EXFAT_I(inode)->flags = p_dir->flags;
+		inode->i_blocks += 1 << sbi->sect_per_clus_bits;
+	}
+
+	return dentry;
+}
+
+/*
+ * Name Resolution Functions :
+ * Zero if it was successful; otherwise nonzero.
+ */
+static int __exfat_resolve_path(struct inode *inode, const unsigned char *path,
+		struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
+		int lookup)
+{
+	int namelen;
+	int lossy = NLS_NAME_NO_LOSSY;
+	struct super_block *sb = inode->i_sb;
+	struct exfat_sb_info *sbi = EXFAT_SB(sb);
+	struct exfat_inode_info *ei = EXFAT_I(inode);
+
+	/* DOT and DOTDOT are handled by VFS layer */
+
+	/* strip all trailing spaces */
+	/* DO NOTHING : Is needed? */
+
+	/* strip all trailing periods */
+	namelen = __exfat_striptail_len(strlen(path), path);
+	if (!namelen)
+		return -ENOENT;
+
+	/* the limitation of linux? */
+	if (strlen(path) > (MAX_NAME_LENGTH * MAX_CHARSET_SIZE))
+		return -ENAMETOOLONG;
+
+	/*
+	 * strip all leading spaces :
+	 * "MS windows 7" supports leading spaces.
+	 * So we should skip this preprocessing for compatibility.
+	 */
+
+	/* file name conversion :
+	 * If lookup case, we allow bad-name for compatibility.
+	 */
+	namelen = exfat_nls_vfsname_to_uni16s(sb, path, namelen, p_uniname,
+			&lossy);
+	if (namelen < 0)
+		return namelen; /* return error value */
+
+	if ((lossy && !lookup) || !namelen)
+		return -EINVAL;
+
+	exfat_chain_set(p_dir, ei->start_clu,
+		EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags);
+
+	return 0;
+}
+
+static inline int exfat_resolve_path(struct inode *inode,
+		const unsigned char *path, struct exfat_chain *dir,
+		struct exfat_uni_name *uni)
+{
+	return __exfat_resolve_path(inode, path, dir, uni, 0);
+}
+
+static inline int exfat_resolve_path_for_lookup(struct inode *inode,
+		const unsigned char *path, struct exfat_chain *dir,
+		struct exfat_uni_name *uni)
+{
+	return __exfat_resolve_path(inode, path, dir, uni, 1);
+}
+
+static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info)
+{
+	return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff);
+}
+
+static int exfat_add_entry(struct inode *inode, const char *path,
+		struct exfat_chain *p_dir, unsigned int type,
+		struct exfat_dir_entry *info)
+{
+	int ret, dentry, num_entries;
+	struct super_block *sb = inode->i_sb;
+	struct exfat_sb_info *sbi = EXFAT_SB(sb);
+	struct exfat_uni_name uniname;
+	struct exfat_chain clu;
+	int clu_size = 0;
+	unsigned int start_clu = FREE_CLUSTER;
+
+	ret = exfat_resolve_path(inode, path, p_dir, &uniname);
+	if (ret)
+		goto out;
+
+	num_entries = exfat_get_num_entries(&uniname);
+	if (num_entries < 0) {
+		ret = num_entries;
+		goto out;
+	}
+
+	/* exfat_find_empty_entry must be called before alloc_cluster() */
+	dentry = exfat_find_empty_entry(inode, p_dir, num_entries);
+	if (dentry < 0) {
+		ret = dentry; /* -EIO or -ENOSPC */
+		goto out;
+	}
+
+	if (type == TYPE_DIR) {
+		ret = exfat_alloc_new_dir(inode, &clu);
+		if (ret)
+			goto out;
+		start_clu = clu.dir;
+		clu_size = sbi->cluster_size;
+	}
+
+	/* update the directory entry */
+	/* fill the dos name directory entry information of the created file.
+	 * the first cluster is not determined yet. (0)
+	 */
+	ret = exfat_init_dir_entry(inode, p_dir, dentry, type,
+		start_clu, clu_size);
+	if (ret)
+		goto out;
+
+	ret = exfat_init_ext_entry(inode, p_dir, dentry, num_entries, &uniname);
+	if (ret)
+		goto out;
+
+	memcpy(&info->dir, p_dir, sizeof(struct exfat_chain));
+	info->entry = dentry;
+	info->flags = ALLOC_NO_FAT_CHAIN;
+	info->type = type;
+
+	if (type == TYPE_FILE) {
+		info->attr = ATTR_ARCHIVE;
+		info->start_clu = EOF_CLUSTER;
+		info->size = 0;
+		info->num_subdirs = 0;
+	} else {
+		int count;
+		struct exfat_chain cdir;
+
+		info->attr = ATTR_SUBDIR;
+		info->start_clu = start_clu;
+		info->size = clu_size;
+
+		exfat_chain_set(&cdir, info->start_clu,
+			EXFAT_B_TO_CLU(info->size, sbi), info->flags);
+		count = exfat_count_dir_entries(sb, &cdir);
+		if (count < 0)
+			return -EIO;
+		info->num_subdirs = count + EXFAT_MIN_SUBDIR;
+	}
+	memset(&info->create_timestamp, 0,
+			sizeof(struct exfat_date_time));
+	memset(&info->modify_timestamp, 0,
+			sizeof(struct exfat_date_time));
+	memset(&info->access_timestamp, 0,
+			sizeof(struct exfat_date_time));
+out:
+	return ret;
+}
+
+static int exfat_create(struct inode *dir, struct dentry *dentry, umode_t mode,
+		bool excl)
+{
+	struct super_block *sb = dir->i_sb;
+	struct inode *inode;
+	struct exfat_chain cdir;
+	struct exfat_dir_entry info;
+	loff_t i_pos;
+	int err;
+
+	mutex_lock(&EXFAT_SB(sb)->s_lock);
+	exfat_set_vol_flags(sb, VOL_DIRTY);
+	err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_FILE,
+		&info);
+	exfat_set_vol_flags(sb, VOL_CLEAN);
+	if (err)
+		goto unlock;
+
+	inode_inc_iversion(dir);
+	dir->i_ctime = dir->i_mtime = dir->i_atime = current_time(dir);
+	if (IS_DIRSYNC(dir))
+		exfat_sync_inode(dir);
+	else
+		mark_inode_dirty(dir);
+
+	i_pos = exfat_make_i_pos(&info);
+	inode = exfat_build_inode(sb, &info, i_pos);
+	if (IS_ERR(inode))
+		goto unlock;
+
+	inode_inc_iversion(inode);
+	inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
+	/* timestamp is already written, so mark_inode_dirty() is unneeded. */
+
+	d_instantiate(dentry, inode);
+unlock:
+	mutex_unlock(&EXFAT_SB(sb)->s_lock);
+	return err;
+}
+
+/* lookup a file */
+static int exfat_find(struct inode *dir, struct qstr *qname,
+		struct exfat_dir_entry *info)
+{
+	int ret, dentry, num_entries, count;
+	struct exfat_chain cdir;
+	struct exfat_uni_name uni_name;
+	struct exfat_dentry *ep, *ep2;
+	struct exfat_entry_set_cache *es = NULL;
+	struct super_block *sb = dir->i_sb;
+	struct exfat_sb_info *sbi = EXFAT_SB(sb);
+	struct exfat_inode_info *ei = EXFAT_I(dir);
+	struct exfat_timestamp tm;
+
+	if (qname->len == 0)
+		return -ENOENT;
+
+	/* check the validity of directory name in the given pathname */
+	ret = exfat_resolve_path_for_lookup(dir, qname->name, &cdir, &uni_name);
+	if (ret)
+		return ret;
+
+	num_entries = exfat_get_num_entries(&uni_name);
+	if (num_entries < 0)
+		return num_entries;
+
+	/* check the validation of hint_stat and initialize it if required */
+	if (ei->version != (inode_peek_iversion_raw(dir) & 0xffffffff)) {
+		ei->hint_stat.clu = cdir.dir;
+		ei->hint_stat.eidx = 0;
+		ei->version = (inode_peek_iversion_raw(dir) & 0xffffffff);
+		ei->hint_femp.eidx = EXFAT_HINT_NONE;
+	}
+
+	/* search the file name for directories */
+	dentry = exfat_find_dir_entry(sb, ei, &cdir, &uni_name,
+			num_entries, TYPE_ALL);
+
+	if ((dentry < 0) && (dentry != -EEXIST))
+		return dentry; /* -error value */
+
+	memcpy(&info->dir, &cdir.dir, sizeof(struct exfat_chain));
+	info->entry = dentry;
+	info->num_subdirs = 0;
+
+	/* root directory itself */
+	if (unlikely(dentry == -EEXIST)) {
+		int num_clu = 0;
+
+		info->type = TYPE_DIR;
+		info->attr = ATTR_SUBDIR;
+		info->flags = ALLOC_FAT_CHAIN;
+		info->start_clu = sbi->root_dir;
+		memset(&info->create_timestamp, 0,
+				sizeof(struct exfat_date_time));
+		memset(&info->modify_timestamp, 0,
+				sizeof(struct exfat_date_time));
+		memset(&info->access_timestamp, 0,
+				sizeof(struct exfat_date_time));
+
+		exfat_chain_set(&cdir, sbi->root_dir, 0, ALLOC_FAT_CHAIN);
+		if (exfat_count_num_clusters(sb, &cdir, &num_clu))
+			return -EIO;
+		info->size = num_clu << sbi->cluster_size_bits;
+
+		count = exfat_count_dir_entries(sb, &cdir);
+		if (count < 0)
+			return -EIO;
+
+		info->num_subdirs = count;
+	} else {
+		es = exfat_get_dentry_set(sb, &cdir, dentry, ES_2_ENTRIES, &ep);
+		if (!es)
+			return -EIO;
+		ep2 = ep + 1;
+
+		info->type = exfat_get_entry_type(ep);
+		info->attr = le16_to_cpu(ep->file_attr);
+		info->size = le64_to_cpu(ep2->stream_valid_size);
+		if ((info->type == TYPE_FILE) && (info->size == 0)) {
+			info->flags = ALLOC_NO_FAT_CHAIN;
+			info->start_clu = EOF_CLUSTER;
+		} else {
+			info->flags = ep2->stream_flags;
+			info->start_clu = le32_to_cpu(ep2->stream_start_clu);
+		}
+
+		if (ei->start_clu == FREE_CLUSTER) {
+			exfat_fs_error(sb,
+				"non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)",
+				i_size_read(dir), ei->dir.dir, ei->entry);
+			return -EIO;
+		}
+
+		exfat_get_entry_time(ep, &tm, TM_CREATE);
+		info->create_timestamp.year = tm.year;
+		info->create_timestamp.month = tm.mon;
+		info->create_timestamp.day = tm.day;
+		info->create_timestamp.hour = tm.hour;
+		info->create_timestamp.minute = tm.min;
+		info->create_timestamp.second = tm.sec;
+		info->create_timestamp.milli_second = 0;
+
+		exfat_get_entry_time(ep, &tm, TM_MODIFY);
+		info->modify_timestamp.year = tm.year;
+		info->modify_timestamp.month = tm.mon;
+		info->modify_timestamp.day = tm.day;
+		info->modify_timestamp.hour = tm.hour;
+		info->modify_timestamp.minute = tm.min;
+		info->modify_timestamp.second = tm.sec;
+		info->modify_timestamp.milli_second = 0;
+
+		memset(&info->access_timestamp, 0,
+				sizeof(struct exfat_date_time));
+		kfree(es);
+
+		if (info->type == TYPE_DIR) {
+			exfat_chain_set(&cdir, info->start_clu,
+				EXFAT_B_TO_CLU(info->size, sbi), info->flags);
+			count = exfat_count_dir_entries(sb, &cdir);
+			if (count < 0)
+				return -EIO;
+
+			info->num_subdirs = count + EXFAT_MIN_SUBDIR;
+		}
+	}
+	return 0;
+}
+
+static int exfat_d_anon_disconn(struct dentry *dentry)
+{
+	return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED);
+}
+
+static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry,
+		unsigned int flags)
+{
+	struct super_block *sb = dir->i_sb;
+	struct inode *inode;
+	struct dentry *alias;
+	struct exfat_dir_entry info;
+	int err;
+	loff_t i_pos;
+	mode_t i_mode;
+
+	mutex_lock(&EXFAT_SB(sb)->s_lock);
+	err = exfat_find(dir, &dentry->d_name, &info);
+	if (err) {
+		if (err == -ENOENT) {
+			inode = NULL;
+			goto out;
+		}
+		goto unlock;
+	}
+
+	i_pos = exfat_make_i_pos(&info);
+	inode = exfat_build_inode(sb, &info, i_pos);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto unlock;
+	}
+
+	i_mode = inode->i_mode;
+	alias = d_find_alias(inode);
+
+	/*
+	 * Checking "alias->d_parent == dentry->d_parent" to make sure
+	 * FS is not corrupted (especially double linked dir).
+	 */
+	if (alias && alias->d_parent == dentry->d_parent &&
+			!exfat_d_anon_disconn(alias)) {
+
+		/*
+		 * Unhashed alias is able to exist because of revalidate()
+		 * called by lookup_fast. You can easily make this status
+		 * by calling create and lookup concurrently
+		 * In such case, we reuse an alias instead of new dentry
+		 */
+		if (d_unhashed(alias)) {
+			WARN_ON(alias->d_name.hash_len !=
+				dentry->d_name.hash_len);
+			exfat_msg(sb, KERN_INFO,
+				"rehashed a dentry(%p) in read lookup", alias);
+			d_drop(dentry);
+			d_rehash(alias);
+		} else if (!S_ISDIR(i_mode)) {
+			/*
+			 * This inode has non anonymous-DCACHE_DISCONNECTED
+			 * dentry. This means, the user did ->lookup() by an
+			 * another name (longname vs 8.3 alias of it) in past.
+			 *
+			 * Switch to new one for reason of locality if possible.
+			 */
+			d_move(alias, dentry);
+		}
+		iput(inode);
+		mutex_unlock(&EXFAT_SB(sb)->s_lock);
+		return alias;
+	}
+	dput(alias);
+out:
+	/* initialize d_time even though it is positive dentry */
+	dentry->d_time = inode_peek_iversion_raw(dir);
+	mutex_unlock(&EXFAT_SB(sb)->s_lock);
+	if (!inode)
+		exfat_d_version_set(dentry, inode_query_iversion(dir));
+
+	return d_splice_alias(inode, dentry);
+unlock:
+	mutex_unlock(&EXFAT_SB(sb)->s_lock);
+	return ERR_PTR(err);
+}
+
+/* remove an entry, BUT don't truncate */
+static int exfat_unlink(struct inode *dir, struct dentry *dentry)
+{
+	struct exfat_chain *cdir;
+	struct exfat_dentry *ep;
+	struct super_block *sb = dir->i_sb;
+	struct inode *inode = dentry->d_inode;
+	struct exfat_inode_info *ei = EXFAT_I(inode);
+	struct buffer_head *bh;
+	sector_t sector;
+	int num_entries, entry, err = 0;
+
+	mutex_lock(&EXFAT_SB(sb)->s_lock);
+	cdir = exfat_chain_dup(&ei->dir);
+	if (!cdir) {
+		err = -ENOMEM;
+		goto unlock;
+	}
+
+	entry = ei->entry;
+
+	if (ei->dir.dir == DIR_DELETED) {
+		exfat_msg(sb, KERN_ERR, "abnormal access to deleted dentry");
+		err = -ENOENT;
+		goto unlock;
+	}
+
+	ep = exfat_get_dentry(sb, cdir, entry, &bh, &sector);
+	if (!ep) {
+		err = -EIO;
+		goto unlock;
+	}
+	num_entries = exfat_count_ext_entries(sb, cdir, entry, ep);
+	if (num_entries < 0) {
+		err = -EIO;
+		brelse(bh);
+		goto unlock;
+	}
+	num_entries++;
+	brelse(bh);
+
+	exfat_set_vol_flags(sb, VOL_DIRTY);
+	/* update the directory entry */
+	if (exfat_remove_entries(dir, cdir, entry, 0, num_entries)) {
+		err = -EIO;
+		goto unlock;
+	}
+
+	/* This doesn't modify ei */
+	ei->dir.dir = DIR_DELETED;
+	exfat_set_vol_flags(sb, VOL_CLEAN);
+
+	inode_inc_iversion(dir);
+	dir->i_mtime = dir->i_atime = current_time(dir);
+	if (IS_DIRSYNC(dir))
+		exfat_sync_inode(dir);
+	else
+		mark_inode_dirty(dir);
+
+	clear_nlink(inode);
+	inode->i_mtime = inode->i_atime = current_time(inode);
+	exfat_unhash_inode(inode);
+	dentry->d_time = inode_peek_iversion_raw(dir);
+	exfat_d_version_set(dentry, inode_query_iversion(dir));
+unlock:
+	mutex_unlock(&EXFAT_SB(sb)->s_lock);
+	kfree(cdir);
+	return err;
+}
+
+static int exfat_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+{
+	struct super_block *sb = dir->i_sb;
+	struct inode *inode;
+	struct exfat_dir_entry info;
+	struct exfat_chain cdir;
+	loff_t i_pos;
+	int err;
+
+	mutex_lock(&EXFAT_SB(sb)->s_lock);
+	exfat_set_vol_flags(sb, VOL_DIRTY);
+	err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_DIR,
+		&info);
+	exfat_set_vol_flags(sb, VOL_CLEAN);
+	if (err)
+		goto unlock;
+
+	inode_inc_iversion(dir);
+	dir->i_ctime = dir->i_mtime = dir->i_atime = current_time(dir);
+	if (IS_DIRSYNC(dir))
+		exfat_sync_inode(dir);
+	else
+		mark_inode_dirty(dir);
+	inc_nlink(dir);
+
+	i_pos = exfat_make_i_pos(&info);
+	inode = exfat_build_inode(sb, &info, i_pos);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto unlock;
+	}
+
+	inode_inc_iversion(inode);
+	inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
+	/* timestamp is already written, so mark_inode_dirty() is unneeded. */
+
+	d_instantiate(dentry, inode);
+
+unlock:
+	mutex_unlock(&EXFAT_SB(sb)->s_lock);
+	return err;
+}
+
+static int exfat_check_dir_empty(struct super_block *sb,
+		struct exfat_chain *p_dir)
+{
+	int i, ret = 0;
+	int dentries_per_clu;
+	unsigned int type;
+	struct exfat_chain *clu;
+	struct exfat_dentry *ep;
+	struct exfat_sb_info *sbi = EXFAT_SB(sb);
+	struct buffer_head *bh;
+
+	dentries_per_clu = sbi->dentries_per_clu;
+
+	clu = exfat_chain_dup(p_dir);
+
+	while (clu->dir != EOF_CLUSTER) {
+		for (i = 0; i < dentries_per_clu; i++) {
+			ep = exfat_get_dentry(sb, clu, i, &bh, NULL);
+			if (!ep) {
+				ret = -EIO;
+				goto free_clu;
+			}
+			type = exfat_get_entry_type(ep);
+			brelse(bh);
+			if (type == TYPE_UNUSED)
+				goto free_clu;
+
+			if (type != TYPE_FILE && type != TYPE_DIR)
+				continue;
+
+			ret = -ENOTEMPTY;
+			goto free_clu;
+		}
+
+		if (clu->flags == ALLOC_NO_FAT_CHAIN) {
+			if (--clu->size > 0)
+				clu->dir++;
+			else
+				clu->dir = EOF_CLUSTER;
+		} else {
+			if (exfat_get_next_cluster(sb, &(clu->dir))) {
+				ret = -EIO;
+				goto free_clu;
+			}
+		}
+	}
+
+free_clu:
+	kfree(clu);
+	return ret;
+}
+
+static int exfat_rmdir(struct inode *dir, struct dentry *dentry)
+{
+	struct inode *inode = dentry->d_inode;
+	struct exfat_dentry *ep;
+	struct exfat_chain *cdir, clu_to_free;
+	struct super_block *sb = inode->i_sb;
+	struct exfat_sb_info *sbi = EXFAT_SB(sb);
+	struct exfat_inode_info *ei = EXFAT_I(inode);
+	struct buffer_head *bh;
+	sector_t sector;
+	int num_entries, entry, err;
+
+	mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
+
+	cdir = exfat_chain_dup(&ei->dir);
+	entry = ei->entry;
+
+	if (ei->dir.dir == DIR_DELETED) {
+		exfat_msg(sb, KERN_ERR, "abnormal access to deleted dentry");
+		err = -ENOENT;
+		goto unlock;
+	}
+
+	exfat_set_vol_flags(sb, VOL_DIRTY);
+	exfat_chain_set(&clu_to_free, ei->start_clu,
+		EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags);
+
+	err = exfat_check_dir_empty(sb, &clu_to_free);
+	if (err) {
+		if (err == -EIO)
+			exfat_msg(sb, KERN_ERR,
+				"failed to exfat_check_dir_empty : err(%d)",
+				err);
+		goto unlock;
+	}
+
+	ep = exfat_get_dentry(sb, cdir, entry, &bh, &sector);
+	if (!ep) {
+		err = -EIO;
+		goto unlock;
+	}
+
+	num_entries = exfat_count_ext_entries(sb, cdir, entry, ep);
+	if (num_entries < 0) {
+		err = -EIO;
+		brelse(bh);
+		goto unlock;
+	}
+	num_entries++;
+	brelse(bh);
+
+	err = exfat_remove_entries(dir, cdir, entry, 0, num_entries);
+	if (err) {
+		exfat_msg(sb, KERN_ERR,
+				"failed to exfat_remove_entries : err(%d)",
+				err);
+		goto unlock;
+	}
+	ei->dir.dir = DIR_DELETED;
+	exfat_set_vol_flags(sb, VOL_CLEAN);
+
+	inode_inc_iversion(dir);
+	dir->i_mtime = dir->i_atime = current_time(dir);
+	if (IS_DIRSYNC(dir))
+		exfat_sync_inode(dir);
+	else
+		mark_inode_dirty(dir);
+	drop_nlink(dir);
+
+	clear_nlink(inode);
+	inode->i_mtime = inode->i_atime = current_time(inode);
+	exfat_unhash_inode(inode);
+	dentry->d_time = inode_peek_iversion_raw(dir);
+	exfat_d_version_set(dentry, inode_query_iversion(dir));
+unlock:
+	mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
+	kfree(cdir);
+	return err;
+}
+
+static int exfat_rename_file(struct inode *inode, struct exfat_chain *p_dir,
+		int oldentry, struct exfat_uni_name *p_uniname,
+		struct exfat_inode_info *ei)
+{
+	int ret, num_old_entries, num_new_entries;
+	sector_t sector_old, sector_new;
+	struct exfat_dentry *epold, *epnew;
+	struct super_block *sb = inode->i_sb;
+	struct buffer_head *new_bh, *old_bh;
+	int sync = IS_DIRSYNC(inode);
+
+	epold = exfat_get_dentry(sb, p_dir, oldentry, &old_bh, &sector_old);
+	if (!epold)
+		return -EIO;
+
+	num_old_entries = exfat_count_ext_entries(sb, p_dir, oldentry, epold);
+	if (num_old_entries < 0)
+		return -EIO;
+	num_old_entries++;
+
+	num_new_entries = exfat_get_num_entries(p_uniname);
+	if (num_new_entries < 0)
+		return num_new_entries;
+
+	if (num_old_entries < num_new_entries) {
+		int newentry;
+
+		newentry =
+			exfat_find_empty_entry(inode, p_dir, num_new_entries);
+		if (newentry < 0)
+			return newentry; /* -EIO or -ENOSPC */
+
+		epnew = exfat_get_dentry(sb, p_dir, newentry, &new_bh,
+			&sector_new);
+		if (!epnew)
+			return -EIO;
+
+		memcpy(epnew, epold, DENTRY_SIZE);
+		if (exfat_get_entry_type(epnew) == TYPE_FILE) {
+			epnew->file_attr |= ATTR_ARCHIVE_LE;
+			ei->attr |= ATTR_ARCHIVE;
+		}
+		exfat_update_bh(sb, new_bh, sync);
+		brelse(old_bh);
+		brelse(new_bh);
+
+		epold = exfat_get_dentry(sb, p_dir, oldentry + 1, &old_bh,
+			&sector_old);
+		epnew = exfat_get_dentry(sb, p_dir, newentry + 1, &new_bh,
+			&sector_new);
+		if (!epold || !epnew)
+			return -EIO;
+
+		memcpy(epnew, epold, DENTRY_SIZE);
+		exfat_update_bh(sb, new_bh, sync);
+		brelse(old_bh);
+		brelse(new_bh);
+
+		ret = exfat_init_ext_entry(inode, p_dir, newentry,
+			num_new_entries, p_uniname);
+		if (ret)
+			return ret;
+
+		exfat_remove_entries(inode, p_dir, oldentry, 0,
+			num_old_entries);
+		ei->entry = newentry;
+	} else {
+		if (exfat_get_entry_type(epold) == TYPE_FILE) {
+			epold->file_attr |= ATTR_ARCHIVE_LE;
+			ei->attr |= ATTR_ARCHIVE;
+		}
+		exfat_update_bh(sb, old_bh, sync);
+		brelse(old_bh);
+		ret = exfat_init_ext_entry(inode, p_dir, oldentry,
+			num_new_entries, p_uniname);
+		if (ret)
+			return ret;
+
+		exfat_remove_entries(inode, p_dir, oldentry, num_new_entries,
+			num_old_entries);
+	}
+	return 0;
+}
+
+static int exfat_move_file(struct inode *inode, struct exfat_chain *p_olddir,
+		int oldentry, struct exfat_chain *p_newdir,
+		struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei)
+{
+	int ret, newentry, num_new_entries, num_old_entries;
+	sector_t sector_mov, sector_new;
+	struct exfat_dentry *epmov, *epnew;
+	struct super_block *sb = inode->i_sb;
+	struct buffer_head *mov_bh, *new_bh;
+
+	epmov = exfat_get_dentry(sb, p_olddir, oldentry, &mov_bh, &sector_mov);
+	if (!epmov)
+		return -EIO;
+
+	/* check if the source and target directory is the same */
+	if (exfat_get_entry_type(epmov) == TYPE_DIR &&
+	    le32_to_cpu(epmov->stream_start_clu) == p_newdir->dir)
+		return -EINVAL;
+
+	num_old_entries = exfat_count_ext_entries(sb, p_olddir, oldentry,
+		epmov);
+	if (num_old_entries < 0)
+		return -EIO;
+	num_old_entries++;
+
+	num_new_entries = exfat_get_num_entries(p_uniname);
+	if (num_new_entries < 0)
+		return num_new_entries;
+
+	newentry = exfat_find_empty_entry(inode, p_newdir, num_new_entries);
+	if (newentry < 0)
+		return newentry; /* -EIO or -ENOSPC */
+
+	epnew = exfat_get_dentry(sb, p_newdir, newentry, &new_bh, &sector_new);
+	if (!epnew)
+		return -EIO;
+
+	memcpy(epnew, epmov, DENTRY_SIZE);
+	if (exfat_get_entry_type(epnew) == TYPE_FILE) {
+		epnew->file_attr |= ATTR_ARCHIVE_LE;
+		ei->attr |= ATTR_ARCHIVE;
+	}
+	exfat_update_bh(sb, new_bh, IS_DIRSYNC(inode));
+	brelse(mov_bh);
+	brelse(new_bh);
+
+	epmov = exfat_get_dentry(sb, p_olddir, oldentry + 1, &mov_bh,
+		&sector_mov);
+	epnew = exfat_get_dentry(sb, p_newdir, newentry + 1, &new_bh,
+		&sector_new);
+	if (!epmov || !epnew)
+		return -EIO;
+
+	memcpy(epnew, epmov, DENTRY_SIZE);
+	exfat_update_bh(sb, new_bh, IS_DIRSYNC(inode));
+	brelse(mov_bh);
+	brelse(new_bh);
+
+	ret = exfat_init_ext_entry(inode, p_newdir, newentry, num_new_entries,
+		p_uniname);
+	if (ret)
+		return ret;
+
+	exfat_remove_entries(inode, p_olddir, oldentry, 0, num_old_entries);
+
+	exfat_chain_set(&ei->dir, p_newdir->dir, p_newdir->size,
+		p_newdir->flags);
+
+	ei->entry = newentry;
+	return 0;
+}
+
+static void exfat_update_parent_info(struct exfat_inode_info *ei,
+		struct inode *parent_inode)
+{
+	struct exfat_sb_info *sbi = EXFAT_SB(parent_inode->i_sb);
+	struct exfat_inode_info *parent_ei = EXFAT_I(parent_inode);
+	loff_t parent_isize = i_size_read(parent_inode);
+
+	/*
+	 * the problem that struct exfat_inode_info caches wrong parent info.
+	 *
+	 * because of flag-mismatch of ei->dir,
+	 * there is abnormal traversing cluster chain.
+	 */
+	if (unlikely(parent_ei->flags != ei->dir.flags ||
+		     parent_isize != EXFAT_CLU_TO_B(ei->dir.size, sbi) ||
+		     parent_ei->start_clu != ei->dir.dir)) {
+		exfat_chain_set(&ei->dir, parent_ei->start_clu,
+			EXFAT_B_TO_CLU_ROUND_UP(parent_isize, sbi),
+			parent_ei->flags);
+	}
+}
+
+/* rename or move a old file into a new file */
+static int __exfat_rename(struct inode *old_parent_inode,
+		struct exfat_inode_info *ei, struct inode *new_parent_inode,
+		struct dentry *new_dentry)
+{
+	int ret;
+	int dentry;
+	struct exfat_chain *olddir, newdir;
+	struct exfat_chain *p_dir = NULL;
+	struct exfat_uni_name uni_name;
+	struct exfat_dentry *ep;
+	struct super_block *sb = old_parent_inode->i_sb;
+	struct exfat_sb_info *sbi = EXFAT_SB(sb);
+	const unsigned char *new_path = new_dentry->d_name.name;
+	struct inode *new_inode = new_dentry->d_inode;
+	int num_entries;
+	struct exfat_inode_info *new_ei = NULL;
+	unsigned int new_entry_type = TYPE_UNUSED;
+	int new_entry = 0;
+	struct buffer_head *old_bh, *new_bh = NULL;
+
+	/* check the validity of pointer parameters */
+	if (new_path == NULL || strlen(new_path) == 0)
+		return -EINVAL;
+
+	if (ei->dir.dir == DIR_DELETED) {
+		exfat_msg(sb, KERN_ERR,
+				"abnormal access to deleted source dentry");
+		return -ENOENT;
+	}
+
+	exfat_update_parent_info(ei, old_parent_inode);
+
+	olddir = exfat_chain_dup(&ei->dir);
+	dentry = ei->entry;
+
+	ep = exfat_get_dentry(sb, olddir, dentry, &old_bh, NULL);
+	if (!ep) {
+		ret = -EIO;
+		goto out;
+	}
+	brelse(old_bh);
+
+	/* check whether new dir is existing directory and empty */
+	if (new_inode) {
+		ret = -EIO;
+		new_ei = EXFAT_I(new_inode);
+
+		if (new_ei->dir.dir == DIR_DELETED) {
+			exfat_msg(sb, KERN_ERR,
+				"abnormal access to deleted target dentry");
+			goto out;
+		}
+
+		exfat_update_parent_info(new_ei, new_parent_inode);
+
+		p_dir = &(new_ei->dir);
+		new_entry = new_ei->entry;
+		ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh, NULL);
+		if (!ep)
+			goto out;
+
+		new_entry_type = exfat_get_entry_type(ep);
+		brelse(new_bh);
+
+		/* if new_inode exists, update ei */
+		if (new_entry_type == TYPE_DIR) {
+			struct exfat_chain new_clu;
+
+			new_clu.dir = new_ei->start_clu;
+			new_clu.size =
+				EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
+				sbi);
+			new_clu.flags = new_ei->flags;
+
+			ret = exfat_check_dir_empty(sb, &new_clu);
+			if (ret)
+				goto out;
+		}
+	}
+
+	/* check the validity of directory name in the given new pathname */
+	ret = exfat_resolve_path(new_parent_inode, new_path, &newdir,
+			&uni_name);
+	if (ret)
+		goto out;
+
+	exfat_set_vol_flags(sb, VOL_DIRTY);
+
+	if (olddir->dir == newdir.dir)
+		ret = exfat_rename_file(new_parent_inode, olddir, dentry,
+				&uni_name, ei);
+	else
+		ret = exfat_move_file(new_parent_inode, olddir, dentry,
+				&newdir, &uni_name, ei);
+
+	if (!ret && new_inode) {
+		/* delete entries of new_dir */
+		ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh, NULL);
+		if (!ep) {
+			ret = -EIO;
+			goto del_out;
+		}
+
+		num_entries = exfat_count_ext_entries(sb, p_dir, new_entry, ep);
+		if (num_entries < 0) {
+			ret = -EIO;
+			goto del_out;
+		}
+		brelse(new_bh);
+
+		if (exfat_remove_entries(new_inode, p_dir, new_entry, 0,
+				num_entries + 1)) {
+			ret = -EIO;
+			goto del_out;
+		}
+
+		/* Free the clusters if new_inode is a dir(as if exfat_rmdir) */
+		if (new_entry_type == TYPE_DIR) {
+			/* new_ei, new_clu_to_free */
+			struct exfat_chain new_clu_to_free;
+
+			exfat_chain_set(&new_clu_to_free, new_ei->start_clu,
+				EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
+				sbi), new_ei->flags);
+
+			if (exfat_free_cluster(new_inode, &new_clu_to_free)) {
+				/* just set I/O error only */
+				ret = -EIO;
+			}
+
+			i_size_write(new_inode, 0);
+			new_ei->start_clu = EOF_CLUSTER;
+			new_ei->flags = ALLOC_NO_FAT_CHAIN;
+		}
+del_out:
+		/* Update new_inode ei
+		 * Prevent syncing removed new_inode
+		 * (new_ei is already initialized above code ("if (new_inode)")
+		 */
+		new_ei->dir.dir = DIR_DELETED;
+	}
+	exfat_set_vol_flags(sb, VOL_CLEAN);
+out:
+	kfree(olddir);
+	return ret;
+}
+
+static int exfat_rename(struct inode *old_dir, struct dentry *old_dentry,
+		struct inode *new_dir, struct dentry *new_dentry,
+		unsigned int flags)
+{
+	struct inode *old_inode, *new_inode;
+	struct super_block *sb = old_dir->i_sb;
+	loff_t i_pos;
+	int err;
+
+	/*
+	 * The VFS already checks for existence, so for local filesystems
+	 * the RENAME_NOREPLACE implementation is equivalent to plain rename.
+	 * Don't support any other flags
+	 */
+	if (flags & ~RENAME_NOREPLACE)
+		return -EINVAL;
+
+	mutex_lock(&EXFAT_SB(sb)->s_lock);
+	old_inode = old_dentry->d_inode;
+	new_inode = new_dentry->d_inode;
+
+	err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry);
+	if (err)
+		goto unlock;
+
+	inode_inc_iversion(new_dir);
+	new_dir->i_ctime = new_dir->i_mtime = new_dir->i_atime =
+		current_time(new_dir);
+	if (IS_DIRSYNC(new_dir))
+		exfat_sync_inode(new_dir);
+	else
+		mark_inode_dirty(new_dir);
+
+	i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) |
+		(EXFAT_I(old_inode)->entry & 0xffffffff);
+	exfat_unhash_inode(old_inode);
+	exfat_hash_inode(old_inode, i_pos);
+	if (IS_DIRSYNC(new_dir))
+		exfat_sync_inode(old_inode);
+	else
+		mark_inode_dirty(old_inode);
+
+	if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
+		drop_nlink(old_dir);
+		if (!new_inode)
+			inc_nlink(new_dir);
+	}
+
+	inode_inc_iversion(old_dir);
+	old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir);
+	if (IS_DIRSYNC(old_dir))
+		exfat_sync_inode(old_dir);
+	else
+		mark_inode_dirty(old_dir);
+
+	if (new_inode) {
+		exfat_unhash_inode(new_inode);
+
+		/* skip drop_nlink if new_inode already has been dropped */
+		if (new_inode->i_nlink) {
+			drop_nlink(new_inode);
+			if (S_ISDIR(new_inode->i_mode))
+				drop_nlink(new_inode);
+		} else {
+			exfat_msg(sb, KERN_WARNING,
+					"abnormal access to an inode dropped");
+			WARN_ON(new_inode->i_nlink == 0);
+		}
+		new_inode->i_ctime = current_time(new_inode);
+	}
+
+unlock:
+	mutex_unlock(&EXFAT_SB(sb)->s_lock);
+	return err;
+}
+
+const struct inode_operations exfat_dir_inode_operations = {
+	.create		= exfat_create,
+	.lookup		= exfat_lookup,
+	.unlink		= exfat_unlink,
+	.mkdir		= exfat_mkdir,
+	.rmdir		= exfat_rmdir,
+	.rename		= exfat_rename,
+	.setattr	= exfat_setattr,
+	.getattr	= exfat_getattr,
+};