exfat: add inode operations
authorNamjae Jeon <namjae.jeon@samsung.com>
Mon, 2 Mar 2020 06:21:34 +0000 (15:21 +0900)
committerAl Viro <viro@zeniv.linux.org.uk>
Fri, 6 Mar 2020 02:00:40 +0000 (21:00 -0500)
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>
Reviewed-by: Pali Rohár <pali.rohar@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
fs/exfat/inode.c [new file with mode: 0644]
fs/exfat/namei.c [new file with mode: 0644]

diff --git a/fs/exfat/inode.c b/fs/exfat/inode.c
new file mode 100644 (file)
index 0000000..0688749
--- /dev/null
@@ -0,0 +1,671 @@
+// 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"
+
+static int __exfat_write_inode(struct inode *inode, int sync)
+{
+       int ret = -EIO;
+       unsigned long long on_disk_size;
+       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);
+       bool is_dir = (ei->type == TYPE_DIR) ? true : false;
+
+       if (inode->i_ino == EXFAT_ROOT_INO)
+               return 0;
+
+       /*
+        * 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->dentry.file.attr = cpu_to_le16(exfat_make_attr(inode));
+
+       /* set FILE_INFO structure using the acquired struct exfat_dentry */
+       exfat_set_entry_time(sbi, &ei->i_crtime,
+                       &ep->dentry.file.create_tz,
+                       &ep->dentry.file.create_time,
+                       &ep->dentry.file.create_date,
+                       &ep->dentry.file.create_time_ms);
+       exfat_set_entry_time(sbi, &inode->i_mtime,
+                       &ep->dentry.file.modify_tz,
+                       &ep->dentry.file.modify_time,
+                       &ep->dentry.file.modify_date,
+                       &ep->dentry.file.modify_time_ms);
+       exfat_set_entry_time(sbi, &inode->i_atime,
+                       &ep->dentry.file.access_tz,
+                       &ep->dentry.file.access_time,
+                       &ep->dentry.file.access_date,
+                       NULL);
+
+       /* File size should be zero if there is no cluster allocated */
+       on_disk_size = i_size_read(inode);
+
+       if (ei->start_clu == EXFAT_EOF_CLUSTER)
+               on_disk_size = 0;
+
+       ep2->dentry.stream.valid_size = cpu_to_le64(on_disk_size);
+       ep2->dentry.stream.size = ep2->dentry.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 = EXFAT_EOF_CLUSTER;
+               return 0;
+       }
+
+       *clu = last_clu = ei->start_clu;
+
+       if (ei->flags == ALLOC_NO_FAT_CHAIN) {
+               if (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) {
+                       last_clu += clu_offset - 1;
+
+                       if (clu_offset == num_clusters)
+                               *clu = EXFAT_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 != EXFAT_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 != EXFAT_EOF_CLUSTER) {
+                       last_clu = *clu;
+                       if (exfat_get_next_cluster(sb, clu))
+                               return -EIO;
+                       clu_offset--;
+               }
+       }
+
+       if (*clu == EXFAT_EOF_CLUSTER) {
+               exfat_set_vol_flags(sb, VOL_DIRTY);
+
+               new_clu.dir = (last_clu == EXFAT_EOF_CLUSTER) ?
+                               EXFAT_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 == EXFAT_EOF_CLUSTER ||
+                   new_clu.dir == EXFAT_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 == EXFAT_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->dentry.stream.flags != ei->flags)
+                                       ep->dentry.stream.flags = ei->flags;
+
+                               if (le32_to_cpu(ep->dentry.stream.start_clu) !=
+                                               ei->start_clu)
+                                       ep->dentry.stream.start_clu =
+                                               cpu_to_le32(ei->start_clu);
+
+                               ep->dentry.stream.valid_size =
+                                       cpu_to_le64(i_size_read(inode));
+                               ep->dentry.stream.size =
+                                       ep->dentry.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_map_new_buffer(struct exfat_inode_info *ei,
+               struct buffer_head *bh, loff_t pos)
+{
+       if (buffer_delay(bh) && pos > ei->i_size_aligned)
+               return -EIO;
+       set_buffer_new(bh);
+
+       /*
+        * Adjust i_size_aligned if i_size_ondisk is bigger than it.
+        */
+       if (ei->i_size_ondisk > ei->i_size_aligned)
+               ei->i_size_aligned = ei->i_size_ondisk;
+       return 0;
+}
+
+static int exfat_get_block(struct inode *inode, sector_t iblock,
+               struct buffer_head *bh_result, int create)
+{
+       struct exfat_inode_info *ei = EXFAT_I(inode);
+       struct super_block *sb = inode->i_sb;
+       struct exfat_sb_info *sbi = EXFAT_SB(sb);
+       unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
+       int err = 0;
+       unsigned long mapped_blocks = 0;
+       unsigned int cluster, sec_offset;
+       sector_t last_block;
+       sector_t phys = 0;
+       loff_t pos;
+
+       mutex_lock(&sbi->s_lock);
+       last_block = EXFAT_B_TO_BLK_ROUND_UP(i_size_read(inode), sb);
+       if (iblock >= last_block && !create)
+               goto done;
+
+       /* Is this block already allocated? */
+       err = exfat_map_cluster(inode, iblock >> sbi->sect_per_clus_bits,
+                       &cluster, 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 (cluster == EXFAT_EOF_CLUSTER)
+               goto done;
+
+       /* sector offset in cluster */
+       sec_offset = iblock & (sbi->sect_per_clus - 1);
+
+       phys = exfat_cluster_to_sector(sbi, cluster) + sec_offset;
+       mapped_blocks = sbi->sect_per_clus - sec_offset;
+       max_blocks = min(mapped_blocks, max_blocks);
+
+       /* Treat newly added block / cluster */
+       if (iblock < last_block)
+               create = 0;
+
+       if (create || buffer_delay(bh_result)) {
+               pos = EXFAT_BLK_TO_B((iblock + 1), sb);
+               if (ei->i_size_ondisk < pos)
+                       ei->i_size_ondisk = pos;
+       }
+
+       if (create) {
+               err = exfat_map_new_buffer(ei, bh_result, pos);
+               if (err) {
+                       exfat_fs_error(sb,
+                                       "requested for bmap out of range(pos : (%llu) > i_size_aligned(%llu)\n",
+                                       pos, ei->i_size_aligned);
+                       goto unlock_ret;
+               }
+       }
+
+       if (buffer_delay(bh_result))
+               clear_buffer_delay(bh_result);
+       map_bh(bh_result, sb, phys);
+done:
+       bh_result->b_size = EXFAT_BLK_TO_B(max_blocks, sb);
+unlock_ret:
+       mutex_unlock(&sbi->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;
+}
+
+/*
+ * exfat_block_truncate_page() zeroes out a mapping from file offset `from'
+ * up to the end of the block which corresponds to `from'.
+ * This is required during truncate to physically zeroout the tail end
+ * of that block so it doesn't yield old data if the file is later grown.
+ * Also, avoid causing failure from fsx for cases of "data past EOF"
+ */
+int exfat_block_truncate_page(struct inode *inode, loff_t from)
+{
+       return block_truncate_page(inode->i_mapping, from, exfat_get_block);
+}
+
+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 = EXFAT_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;
+       inode->i_mtime = info->mtime;
+       inode->i_ctime = info->mtime;
+       ei->i_crtime = info->crtime;
+       inode->i_atime = info->atime;
+
+       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 (file)
index 0000000..a8681d9
--- /dev/null
@@ -0,0 +1,1448 @@
+// 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_d_revalidate(struct dentry *dentry, unsigned int flags)
+{
+       int ret;
+
+       if (flags & LOOKUP_RCU)
+               return -ECHILD;
+
+       /*
+        * 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;
+
+       spin_lock(&dentry->d_lock);
+       ret = inode_eq_iversion(d_inode(dentry->d_parent),
+                       exfat_d_version(dentry));
+       spin_unlock(&dentry->d_lock);
+       return ret;
+}
+
+/* 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;
+}
+
+/*
+ * Compute the hash for the exfat name corresponding to the dentry.  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)
+{
+       struct super_block *sb = dentry->d_sb;
+       struct nls_table *t = EXFAT_SB(sb)->nls_io;
+       const unsigned char *name = qstr->name;
+       unsigned int len = exfat_striptail_len(qstr->len, qstr->name);
+       unsigned long hash = init_name_hash(dentry);
+       int i, charlen;
+       wchar_t c;
+
+       for (i = 0; i < len; i += charlen) {
+               charlen = t->char2uni(&name[i], len - i, &c);
+               if (charlen < 0)
+                       return charlen;
+               hash = partial_name_hash(exfat_toupper(sb, c), hash);
+       }
+
+       qstr->hash = end_name_hash(hash);
+       return 0;
+}
+
+static int exfat_d_cmp(const struct dentry *dentry, unsigned int len,
+               const char *str, const struct qstr *name)
+{
+       struct super_block *sb = dentry->d_sb;
+       struct nls_table *t = EXFAT_SB(sb)->nls_io;
+       unsigned int alen = exfat_striptail_len(name->len, name->name);
+       unsigned int blen = exfat_striptail_len(len, str);
+       wchar_t c1, c2;
+       int charlen, i;
+
+       if (alen != blen)
+               return 1;
+
+       for (i = 0; i < len; i += charlen) {
+               charlen = t->char2uni(&name->name[i], alen - i, &c1);
+               if (charlen < 0)
+                       return 1;
+               if (charlen != t->char2uni(&str[i], blen - i, &c2))
+                       return 1;
+
+               if (exfat_toupper(sb, c1) != exfat_toupper(sb, c2))
+                       return 1;
+       }
+
+       return 0;
+}
+
+const struct dentry_operations exfat_dentry_ops = {
+       .d_revalidate   = exfat_d_revalidate,
+       .d_hash         = exfat_d_hash,
+       .d_compare      = exfat_d_cmp,
+};
+
+static int exfat_utf8_d_hash(const struct dentry *dentry, struct qstr *qstr)
+{
+       struct super_block *sb = dentry->d_sb;
+       const unsigned char *name = qstr->name;
+       unsigned int len = exfat_striptail_len(qstr->len, qstr->name);
+       unsigned long hash = init_name_hash(dentry);
+       int i, charlen;
+       unicode_t u;
+
+       for (i = 0; i < len; i += charlen) {
+               charlen = utf8_to_utf32(&name[i], len - i, &u);
+               if (charlen < 0)
+                       return charlen;
+
+               /*
+                * Convert to UTF-16: code points above U+FFFF are encoded as
+                * surrogate pairs.
+                * exfat_toupper() works only for code points up to the U+FFFF.
+                */
+               if (u > 0xFFFF) {
+                       hash = partial_name_hash(exfat_high_surrogate(u), hash);
+                       hash = partial_name_hash(exfat_low_surrogate(u), hash);
+               } else {
+                       hash = partial_name_hash(exfat_toupper(sb, u), hash);
+               }
+       }
+
+       qstr->hash = end_name_hash(hash);
+       return 0;
+}
+
+static int exfat_utf8_d_cmp(const struct dentry *dentry, unsigned int len,
+               const char *str, const struct qstr *name)
+{
+       struct super_block *sb = dentry->d_sb;
+       unsigned int alen = exfat_striptail_len(name->len, name->name);
+       unsigned int blen = exfat_striptail_len(len, str);
+       unicode_t u_a, u_b;
+       int charlen, i;
+
+       if (alen != blen)
+               return 1;
+
+       for (i = 0; i < alen; i += charlen) {
+               charlen = utf8_to_utf32(&name->name[i], alen - i, &u_a);
+               if (charlen < 0)
+                       return 1;
+               if (charlen != utf8_to_utf32(&str[i], blen - i, &u_b))
+                       return 1;
+
+               if (u_a <= 0xFFFF && u_b <= 0xFFFF) {
+                       if (exfat_toupper(sb, u_a) != exfat_toupper(sb, u_b))
+                               return 1;
+               } else if (u_a > 0xFFFF && u_b > 0xFFFF) {
+                       if (exfat_low_surrogate(u_a) !=
+                                       exfat_low_surrogate(u_b) ||
+                           exfat_high_surrogate(u_a) !=
+                                       exfat_high_surrogate(u_b))
+                               return 1;
+               } else {
+                       return 1;
+               }
+       }
+
+       return 0;
+}
+
+const struct dentry_operations exfat_utf8_dentry_ops = {
+       .d_revalidate   = exfat_d_revalidate,
+       .d_hash         = exfat_utf8_d_hash,
+       .d_compare      = exfat_utf8_d_cmp,
+};
+
+/* 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;
+       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;
+               }
+
+               exfat_chain_dup(&clu, &hint_femp->cur);
+       } else {
+               exfat_chain_dup(&clu, p_dir);
+               dentry = 0;
+       }
+
+       while (clu.dir != EXFAT_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)
+                               return -EIO;
+                       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);
+                                       return -EIO;
+                               }
+
+                               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;
+                               return (dentry - (num_entries - 1));
+                       }
+               }
+
+               if (clu.flags == ALLOC_NO_FAT_CHAIN) {
+                       if (--clu.size > 0)
+                               clu.dir++;
+                       else
+                               clu.dir = EXFAT_EOF_CLUSTER;
+               } else {
+                       if (exfat_get_next_cluster(sb, &clu.dir))
+                               return -EIO;
+               }
+       }
+
+       return -ENOSPC;
+}
+
+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.
+ */
+static 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->dentry.stream.valid_size = cpu_to_le64(size);
+                       ep->dentry.stream.size = ep->dentry.stream.valid_size;
+                       ep->dentry.stream.flags = p_dir->flags;
+                       exfat_update_bh(sb, bh, IS_DIRSYNC(inode));
+                       brelse(bh);
+                       if (exfat_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);
+
+       /* strip all trailing periods */
+       namelen = exfat_striptail_len(strlen(path), path);
+       if (!namelen)
+               return -ENOENT;
+
+       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_to_utf16(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 = EXFAT_FREE_CLUSTER;
+
+       ret = exfat_resolve_path(inode, path, p_dir, &uniname);
+       if (ret)
+               goto out;
+
+       num_entries = exfat_calc_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 = EXFAT_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->crtime, 0, sizeof(info->crtime));
+       memset(&info->mtime, 0, sizeof(info->mtime));
+       memset(&info->atime, 0, sizeof(info->atime));
+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 = 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 =
+               EXFAT_I(inode)->i_crtime = 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);
+
+       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_calc_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->crtime, 0, sizeof(info->crtime));
+               memset(&info->mtime, 0, sizeof(info->mtime));
+               memset(&info->atime, 0, sizeof(info->atime));
+
+               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->dentry.file.attr);
+               info->size = le64_to_cpu(ep2->dentry.stream.valid_size);
+               if ((info->type == TYPE_FILE) && (info->size == 0)) {
+                       info->flags = ALLOC_NO_FAT_CHAIN;
+                       info->start_clu = EXFAT_EOF_CLUSTER;
+               } else {
+                       info->flags = ep2->dentry.stream.flags;
+                       info->start_clu =
+                               le32_to_cpu(ep2->dentry.stream.start_clu);
+               }
+
+               if (ei->start_clu == EXFAT_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(sbi, &info->crtime,
+                               ep->dentry.file.create_tz,
+                               ep->dentry.file.create_time,
+                               ep->dentry.file.create_date,
+                               ep->dentry.file.create_time_ms);
+               exfat_get_entry_time(sbi, &info->mtime,
+                               ep->dentry.file.modify_tz,
+                               ep->dentry.file.modify_time,
+                               ep->dentry.file.modify_date,
+                               ep->dentry.file.modify_time_ms);
+               exfat_get_entry_time(sbi, &info->atime,
+                               ep->dentry.file.access_tz,
+                               ep->dentry.file.access_time,
+                               ep->dentry.file.access_date,
+                               0);
+               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:
+       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);
+       exfat_chain_dup(&cdir, &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;
+       }
+
+       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);
+       exfat_d_version_set(dentry, inode_query_iversion(dir));
+unlock:
+       mutex_unlock(&EXFAT_SB(sb)->s_lock);
+       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 = 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 =
+               EXFAT_I(inode)->i_crtime = 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, 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;
+
+       exfat_chain_dup(&clu, p_dir);
+
+       while (clu.dir != EXFAT_EOF_CLUSTER) {
+               for (i = 0; i < dentries_per_clu; i++) {
+                       ep = exfat_get_dentry(sb, &clu, i, &bh, NULL);
+                       if (!ep)
+                               return -EIO;
+                       type = exfat_get_entry_type(ep);
+                       brelse(bh);
+                       if (type == TYPE_UNUSED)
+                               return 0;
+
+                       if (type != TYPE_FILE && type != TYPE_DIR)
+                               continue;
+
+                       return -ENOTEMPTY;
+               }
+
+               if (clu.flags == ALLOC_NO_FAT_CHAIN) {
+                       if (--clu.size > 0)
+                               clu.dir++;
+                       else
+                               clu.dir = EXFAT_EOF_CLUSTER;
+               } else {
+                       if (exfat_get_next_cluster(sb, &(clu.dir)))
+                               return -EIO;
+               }
+       }
+
+       return 0;
+}
+
+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);
+
+       exfat_chain_dup(&cdir, &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);
+       exfat_d_version_set(dentry, inode_query_iversion(dir));
+unlock:
+       mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
+       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_calc_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->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
+                       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->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
+                       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->dentry.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_calc_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->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
+               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);
+
+       exfat_chain_dup(&olddir, &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 = EXFAT_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:
+       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 =
+               EXFAT_I(new_dir)->i_crtime = 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 = EXFAT_I(new_inode)->i_crtime =
+                       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,
+};