Commit ee785c15 authored by Yuezhang Mo's avatar Yuezhang Mo Committed by Namjae Jeon
Browse files

exfat: support create zero-size directory 



This commit adds mount option 'zero_size_dir'. If this option
enabled, don't allocate a cluster to directory when creating
it, and set the directory size to 0.

On Windows, a cluster is allocated for a directory when it is
created, so the mount option is disabled by default.

Signed-off-by: default avatarYuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: default avatarAndy Wu <Andy.Wu@sony.com>
Reviewed-by: default avatarAoyama Wataru <wataru.aoyama@sony.com>
Signed-off-by: default avatarNamjae Jeon <linkinjeon@kernel.org>
parent dab48b8f

fs/exfat/dir.c

+6 −6
Original line number Diff line number Diff line
@@ -418,11 +418,13 @@ static void exfat_set_entry_type(struct exfat_dentry *ep, unsigned int type) 
}



static void exfat_init_stream_entry(struct exfat_dentry *ep,

		unsigned char flags, unsigned int start_clu,

		unsigned long long size)

		unsigned int start_clu, unsigned long long size)

{

	exfat_set_entry_type(ep, TYPE_STREAM);

	ep->dentry.stream.flags = flags;

	if (size == 0)

		ep->dentry.stream.flags = ALLOC_FAT_CHAIN;

	else

		ep->dentry.stream.flags = ALLOC_NO_FAT_CHAIN;

	ep->dentry.stream.start_clu = cpu_to_le32(start_clu);

	ep->dentry.stream.valid_size = cpu_to_le64(size);

	ep->dentry.stream.size = cpu_to_le64(size);
@@ -488,9 +490,7 @@ int exfat_init_dir_entry(struct inode *inode, struct exfat_chain *p_dir, 
	if (!ep)

		return -EIO;



	exfat_init_stream_entry(ep,

		(type == TYPE_FILE) ? ALLOC_FAT_CHAIN : ALLOC_NO_FAT_CHAIN,

		start_clu, size);

	exfat_init_stream_entry(ep, start_clu, size);

	exfat_update_bh(bh, IS_DIRSYNC(inode));

	brelse(bh);

fs/exfat/exfat_fs.h

+2 −0
Original line number Diff line number Diff line
@@ -234,6 +234,8 @@ struct exfat_mount_options { 
		 discard:1, /* Issue discard requests on deletions */

		 keep_last_dots:1; /* Keep trailing periods in paths */

	int time_offset; /* Offset of timestamps from UTC (in minutes) */

	/* Support creating zero-size directory, default: false */

	bool zero_size_dir;

};



/*

fs/exfat/namei.c

+5 −2
Original line number Diff line number Diff line
@@ -518,7 +518,7 @@ static int exfat_add_entry(struct inode *inode, const char *path, 
		goto out;

	}



	if (type == TYPE_DIR) {

	if (type == TYPE_DIR && !sbi->options.zero_size_dir) {

		ret = exfat_alloc_new_dir(inode, &clu);

		if (ret)

			goto out;
@@ -551,6 +551,9 @@ static int exfat_add_entry(struct inode *inode, const char *path, 
		info->num_subdirs = 0;

	} else {

		info->attr = EXFAT_ATTR_SUBDIR;

		if (sbi->options.zero_size_dir)

			info->start_clu = EXFAT_EOF_CLUSTER;

		else

			info->start_clu = start_clu;

		info->size = clu_size;

		info->num_subdirs = EXFAT_MIN_SUBDIR;

fs/exfat/super.c

+7 −0
Original line number Diff line number Diff line
@@ -165,6 +165,8 @@ static int exfat_show_options(struct seq_file *m, struct dentry *root) 
		seq_puts(m, ",sys_tz");

	else if (opts->time_offset)

		seq_printf(m, ",time_offset=%d", opts->time_offset);

	if (opts->zero_size_dir)

		seq_puts(m, ",zero_size_dir");

	return 0;

}
@@ -209,6 +211,7 @@ enum { 
	Opt_keep_last_dots,

	Opt_sys_tz,

	Opt_time_offset,

	Opt_zero_size_dir,



	/* Deprecated options */

	Opt_utf8,
@@ -237,6 +240,7 @@ static const struct fs_parameter_spec exfat_parameters[] = { 
	fsparam_flag("keep_last_dots",		Opt_keep_last_dots),

	fsparam_flag("sys_tz",			Opt_sys_tz),

	fsparam_s32("time_offset",		Opt_time_offset),

	fsparam_flag("zero_size_dir",		Opt_zero_size_dir),

	__fsparam(NULL, "utf8",			Opt_utf8, fs_param_deprecated,

		  NULL),

	__fsparam(NULL, "debug",		Opt_debug, fs_param_deprecated,
@@ -305,6 +309,9 @@ static int exfat_parse_param(struct fs_context *fc, struct fs_parameter *param) 
			return -EINVAL;

		opts->time_offset = result.int_32;

		break;

	case Opt_zero_size_dir:

		opts->zero_size_dir = true;

		break;

	case Opt_utf8:

	case Opt_debug:

	case Opt_namecase: