exfat: code cleanup for exfat_readdir()

For the root directory and other directories, the clusters
allocated to them can be obtained from exfat_inode_info, and
there is no need to distinguish them.

And there is no need to initialize atime/ctime/mtime/size in
exfat_readdir(), because exfat_iterate() does not use them.

Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Daniel Palmer <daniel.palmer@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>

Author: YuezhangMo

fs/exfat/dir.c

@@ -82,11 +82,8 @@ static int exfat_readdir(struct inode *inode, loff_t *cpos, struct exfat_dir_ent
 	if (ei->type != TYPE_DIR)
 		return -EPERM;
 
-	if (ei->entry == -1)
-		exfat_chain_set(&dir, sbi->root_dir, 0, ALLOC_FAT_CHAIN);
-	else
-		exfat_chain_set(&dir, ei->start_clu,
-			EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags);
+	exfat_chain_set(&dir, ei->start_clu,
+		EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags);
 
 	dentries_per_clu = sbi->dentries_per_clu;
 	max_dentries = (unsigned int)min_t(u64, MAX_EXFAT_DENTRIES,
@@ -135,21 +132,6 @@ static int exfat_readdir(struct inode *inode, loff_t *cpos, struct exfat_dir_ent
 
 			num_ext = ep->dentry.file.num_ext;
 			dir_entry->attr = le16_to_cpu(ep->dentry.file.attr);
-			exfat_get_entry_time(sbi, &dir_entry->crtime,
-					ep->dentry.file.create_tz,
-					ep->dentry.file.create_time,
-					ep->dentry.file.create_date,
-					ep->dentry.file.create_time_cs);
-			exfat_get_entry_time(sbi, &dir_entry->mtime,
-					ep->dentry.file.modify_tz,
-					ep->dentry.file.modify_time,
-					ep->dentry.file.modify_date,
-					ep->dentry.file.modify_time_cs);
-			exfat_get_entry_time(sbi, &dir_entry->atime,
-					ep->dentry.file.access_tz,
-					ep->dentry.file.access_time,
-					ep->dentry.file.access_date,
-					0);
 
 			*uni_name.name = 0x0;
 			err = exfat_get_uniname_from_ext_entry(sb, &clu, i,
@@ -166,8 +148,6 @@ static int exfat_readdir(struct inode *inode, loff_t *cpos, struct exfat_dir_ent
 			ep = exfat_get_dentry(sb, &clu, i + 1, &bh);
 			if (!ep)
 				return -EIO;
-			dir_entry->size =
-				le64_to_cpu(ep->dentry.stream.valid_size);
 			dir_entry->entry = dentry;
 			brelse(bh);