udf: implement mode and dmode mounting options

"dmode" allows overriding permissions of directories and
"mode" allows overriding permissions of files.

Signed-off-by: Marcin Slusarz <[e-mail]>
Cc: Jan Kara <[e-mail]>
Signed-off-by: Jan Kara <[e-mail]>

Documentation/filesystems/udf.txt

···
 
 	gid=		Set the default group.
 	umask=		Set the default umask.
+	mode=		Set the default file permissions.
+	dmode=		Set the default directory permissions.
 	uid=		Set the default user.
 	bs=		Set the block size.
 	unhide		Show otherwise hidden files.

fs/udf/inode.c

···
 	inode->i_size = le64_to_cpu(fe->informationLength);
 	iinfo->i_lenExtents = inode->i_size;
 
-	inode->i_mode = udf_convert_permissions(fe);
-	inode->i_mode &= ~UDF_SB(inode->i_sb)->s_umask;
+	if (fe->icbTag.fileType != ICBTAG_FILE_TYPE_DIRECTORY &&
+			sbi->s_fmode != -1)
+		inode->i_mode = sbi->s_fmode;
+	else if (fe->icbTag.fileType == ICBTAG_FILE_TYPE_DIRECTORY &&
+			sbi->s_dmode != -1)
+		inode->i_mode = sbi->s_dmode;
+	else
+		inode->i_mode = udf_convert_permissions(fe);
+	inode->i_mode &= ~sbi->s_umask;
 
 	if (iinfo->i_efe == 0) {
 		inode->i_blocks = le64_to_cpu(fe->logicalBlocksRecorded) <<

fs/udf/super.c

···
 	mode_t umask;
 	gid_t gid;
 	uid_t uid;
+	mode_t fmode;
+	mode_t dmode;
 	struct nls_table *nls_map;
 };
 
···
 		seq_printf(seq, ",gid=%u", sbi->s_gid);
 	if (sbi->s_umask != 0)
 		seq_printf(seq, ",umask=%o", sbi->s_umask);
+	if (sbi->s_fmode != -1)
+		seq_printf(seq, ",mode=%o", sbi->s_fmode);
+	if (sbi->s_dmode != -1)
+		seq_printf(seq, ",dmode=%o", sbi->s_dmode);
 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_SESSION_SET))
 		seq_printf(seq, ",session=%u", sbi->s_session);
 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_LASTBLOCK_SET))
···
  *
  *	gid=		Set the default group.
  *	umask=		Set the default umask.
+ *	mode=		Set the default file permissions.
+ *	dmode=		Set the default directory permissions.
  *	uid=		Set the default user.
  *	bs=		Set the block size.
  *	unhide		Show otherwise hidden files.
···
 	Opt_gid, Opt_uid, Opt_umask, Opt_session, Opt_lastblock,
 	Opt_anchor, Opt_volume, Opt_partition, Opt_fileset,
 	Opt_rootdir, Opt_utf8, Opt_iocharset,
-	Opt_err, Opt_uforget, Opt_uignore, Opt_gforget, Opt_gignore
+	Opt_err, Opt_uforget, Opt_uignore, Opt_gforget, Opt_gignore,
+	Opt_fmode, Opt_dmode
 };
 
 static const match_table_t tokens = {
···
 	{Opt_rootdir,	"rootdir=%u"},
 	{Opt_utf8,	"utf8"},
 	{Opt_iocharset,	"iocharset=%s"},
+	{Opt_fmode,     "mode=%o"},
+	{Opt_dmode,     "dmode=%o"},
 	{Opt_err,	NULL}
 };
 
···
 		case Opt_gforget:
 			uopt->flags |= (1 << UDF_FLAG_GID_FORGET);
 			break;
+		case Opt_fmode:
+			if (match_octal(args, &option))
+				return 0;
+			uopt->fmode = option & 0777;
+			break;
+		case Opt_dmode:
+			if (match_octal(args, &option))
+				return 0;
+			uopt->dmode = option & 0777;
+			break;
 		default:
 			printk(KERN_ERR "udf: bad mount option \"%s\" "
 			       "or missing value\n", p);
···
 	uopt.uid   = sbi->s_uid;
 	uopt.gid   = sbi->s_gid;
 	uopt.umask = sbi->s_umask;
+	uopt.fmode = sbi->s_fmode;
+	uopt.dmode = sbi->s_dmode;
 
 	if (!udf_parse_options(options, &uopt, true))
 		return -EINVAL;
···
 	sbi->s_uid   = uopt.uid;
 	sbi->s_gid   = uopt.gid;
 	sbi->s_umask = uopt.umask;
+	sbi->s_fmode = uopt.fmode;
+	sbi->s_dmode = uopt.dmode;
 
 	if (sbi->s_lvid_bh) {
 		int write_rev = le16_to_cpu(udf_sb_lvidiu(sbi)->minUDFWriteRev);
···
 	uopt.uid = -1;
 	uopt.gid = -1;
 	uopt.umask = 0;
+	uopt.fmode = -1;
+	uopt.dmode = -1;
 
 	sbi = kzalloc(sizeof(struct udf_sb_info), GFP_KERNEL);
 	if (!sbi)
···
 	sbi->s_uid = uopt.uid;
 	sbi->s_gid = uopt.gid;
 	sbi->s_umask = uopt.umask;
+	sbi->s_fmode = uopt.fmode;
+	sbi->s_dmode = uopt.dmode;
 	sbi->s_nls_map = uopt.nls_map;
 
 	/* Set the block size for all transfers */

fs/udf/udf_sb.h

···
 	mode_t			s_umask;
 	gid_t			s_gid;
 	uid_t			s_uid;
+	mode_t			s_fmode;
+	mode_t			s_dmode;
 
 	/* Root Info */
 	struct timespec		s_record_time;