fs/ntfs3: Add hidedotfiles option

With this option all files with filename[0] == '.'
will have FILE_ATTRIBUTE_HIDDEN attribute.
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

fs/ntfs3/inode.c

@@ -1257,6 +1257,10 @@ struct inode *ntfs_create_inode(struct user_namespace *mnt_userns,
 		fa = FILE_ATTRIBUTE_ARCHIVE;
 	}
 
+	/* If option "hidedotfiles" then set hidden attribute for dot files. */
+	if (sbi->options->hide_dot_files && name->name[0] == '.')
+		fa |= FILE_ATTRIBUTE_HIDDEN;
+
 	if (!(mode & 0222))
 		fa |= FILE_ATTRIBUTE_READONLY;
 

fs/ntfs3/ntfs_fs.h

@@ -97,6 +97,7 @@ struct ntfs_mount_options {
 	unsigned sparse : 1; /* Create sparse files. */
 	unsigned showmeta : 1; /* Show meta files. */
 	unsigned nohidden : 1; /* Do not show hidden files. */
+	unsigned hide_dot_files : 1; /* Set hidden flag on dot files. */
 	unsigned force : 1; /* RW mount dirty volume. */
 	unsigned noacsrules : 1; /* Exclude acs rules. */
 	unsigned prealloc : 1; /* Preallocate space when file is growing. */

fs/ntfs3/super.c

@@ -247,6 +247,7 @@ enum Opt {
 	Opt_force,
 	Opt_sparse,
 	Opt_nohidden,
+	Opt_hide_dot_files,
 	Opt_showmeta,
 	Opt_acl,
 	Opt_iocharset,
@@ -266,6 +267,7 @@ static const struct fs_parameter_spec ntfs_fs_parameters[] = {
 	fsparam_flag_no("force",		Opt_force),
 	fsparam_flag_no("sparse",		Opt_sparse),
 	fsparam_flag_no("hidden",		Opt_nohidden),
+	fsparam_flag_no("hidedotfiles",		Opt_hide_dot_files),
 	fsparam_flag_no("acl",			Opt_acl),
 	fsparam_flag_no("showmeta",		Opt_showmeta),
 	fsparam_flag_no("prealloc",		Opt_prealloc),
@@ -354,6 +356,9 @@ static int ntfs_fs_parse_param(struct fs_context *fc,
 	case Opt_nohidden:
 		opts->nohidden = result.negated ? 1 : 0;
 		break;
+	case Opt_hide_dot_files:
+		opts->hide_dot_files = result.negated ? 1 : 0;
+		break;
 	case Opt_acl:
 		if (!result.negated)
 #ifdef CONFIG_NTFS3_FS_POSIX_ACL