fat: Fix ATTR_RO for directory

FAT has the ATTR_RO (read-only) attribute. But on Windows, the ATTR_RO
of the directory will be just ignored actually, and is used by only
applications as flag. E.g. it's setted for the customized folder by
Explorer.

http://msdn2.microsoft.com/en-us/library/aa969337.aspx

This adds "rodir" option. If user specified it, ATTR_RO is used as
read-only flag even if it's the directory. Otherwise, inode->i_mode
is not used to hold ATTR_RO (i.e. fat_mode_can_save_ro() returns 0).

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 13 insertions, 4 deletions

diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 7aaa21c..0da04e6 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -797,8 +797,10 @@ static int fat_show_options(struct seq_file *m, struct vfsmount *mnt)
 			seq_puts(m, ",uni_xlate");
 		if (!opts->numtail)
 			seq_puts(m, ",nonumtail");
+		if (opts->rodir)
+			seq_puts(m, ",rodir");
 	}
-	if (sbi->options.flush)
+	if (opts->flush)
 		seq_puts(m, ",flush");
 	if (opts->tz_utc)
 		seq_puts(m, ",tz=UTC");
@@ -814,7 +816,7 @@ enum {
 	Opt_charset, Opt_shortname_lower, Opt_shortname_win95,
 	Opt_shortname_winnt, Opt_shortname_mixed, Opt_utf8_no, Opt_utf8_yes,
 	Opt_uni_xl_no, Opt_uni_xl_yes, Opt_nonumtail_no, Opt_nonumtail_yes,
-	Opt_obsolate, Opt_flush, Opt_tz_utc, Opt_err,
+	Opt_obsolate, Opt_flush, Opt_tz_utc, Opt_rodir, Opt_err,
 };
 
 static const match_table_t fat_tokens = {
@@ -886,6 +888,7 @@ static const match_table_t vfat_tokens = {
 	{Opt_nonumtail_yes, "nonumtail=yes"},
 	{Opt_nonumtail_yes, "nonumtail=true"},
 	{Opt_nonumtail_yes, "nonumtail"},
+	{Opt_rodir, "rodir"},
 	{Opt_err, NULL}
 };
 
@@ -905,10 +908,13 @@ static int parse_options(char *options, int is_vfat, int silent, int *debug,
 	opts->allow_utime = -1;
 	opts->codepage = fat_default_codepage;
 	opts->iocharset = fat_default_iocharset;
-	if (is_vfat)
+	if (is_vfat) {
 		opts->shortname = VFAT_SFN_DISPLAY_LOWER|VFAT_SFN_CREATE_WIN95;
-	else
+		opts->rodir = 0;
+	} else {
 		opts->shortname = 0;
+		opts->rodir = 1;
+	}
 	opts->name_check = 'n';
 	opts->quiet = opts->showexec = opts->sys_immutable = opts->dotsOK =  0;
 	opts->utf8 = opts->unicode_xlate = 0;
@@ -1059,6 +1065,9 @@ static int parse_options(char *options, int is_vfat, int silent, int *debug,
 		case Opt_nonumtail_yes:		/* empty or 1 or yes or true */
 			opts->numtail = 0;	/* negated option */
 			break;
+		case Opt_rodir:
+			opts->rodir = 1;
+			break;
 
 		/* obsolete mount options */
 		case Opt_obsolate: