- Implement -T option to allow to specify a fs type for a vnode-backed memory disk

- Rephrase -t option description (manpage)
- Split long sentences (manpage)

Differential Review:	https://reviews.freebsd.org/D4394

Reviewed by:	mav, wblock (manpage)
Approved by:	mav

sbin/mdmfs/mdmfs.8

@@ -25,7 +25,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd March 7, 2016
+.Dd March 9, 2016
 .Dt MDMFS 8
 .Os
 .Sh NAME
@@ -36,7 +36,7 @@
 driver
 .Sh SYNOPSIS
 .Nm
-.Op Fl DLlMNnPStUX
+.Op Fl DLlMNnPStTUX
 .Op Fl a Ar maxcontig
 .Op Fl b Ar block-size
 .Op Fl c Ar blocks-per-cylinder-group
@@ -51,6 +51,7 @@ driver
 .Op Fl o Ar mount-options
 .Op Fl p Ar permissions
 .Op Fl s Ar size
+.Op Fl T Ar fstype
 .Op Fl v Ar version
 .Op Fl w Ar user : Ns Ar group
 .Ar md-device
@@ -228,10 +229,19 @@ backed disks
 .It Fl t
 Turn on the TRIM enable flag for
 .Xr newfs 8 .
-The
+When used with a file system that issue BIO_DELETE bio requests,
 .Xr md 4
-device supports the BIO_DELETE command, enabling the TRIM on created
-filesystem allows return of freed memory to the system pool.
+returns deleted blocks to the system memory pool.
+.It Fl T Ar fstype
+Specify a file system type for a vnode-backed memory disk.
+Any file system supported by
+.Xr mount 8
+command can be specified.
+This option only makes sense when
+.Fl F
+and
+.Fl P
+are used.
 .It Fl U
 Enable soft-updates on the file system.
 This is the default, and is accepted only
@@ -283,8 +293,8 @@ and
 .Fl n
 options are passed to
 .Xr newfs 8
-with the same letter;
-the
+with the same letter.
+The
 .Fl O
 option is passed to
 .Xr newfs 8
@@ -295,6 +305,12 @@ The
 option is passed to
 .Xr mount 8
 with the same letter.
+The
+.Fl T
+option is passed to
+.Xr mount 8
+as
+.Fl t .
 See the programs that the options are passed to for more information
 on their semantics.
 .Sh EXAMPLES
@@ -335,6 +351,10 @@ Configure a vnode-backed file system and mount its first partition,
 using automatic device numbering:
 .Pp
 .Dl "mdmfs -P -F foo.img mds1a /tmp/"
+.Pp
+Mount a vnode-backed cd9660 file system using automatic device numbering:
+.Pp
+.Dl "mdmfs -T cd9660 -P -F foo.iso md /tmp"
 .Sh COMPATIBILITY
 The
 .Nm

sbin/mdmfs/mdmfs.c

@@ -129,7 +129,7 @@ main(int argc, char **argv)
 	}
 
 	while ((ch = getopt(argc, argv,
-	    "a:b:Cc:Dd:E:e:F:f:hi:LlMm:NnO:o:Pp:Ss:tUv:w:X")) != -1)
+	    "a:b:Cc:Dd:E:e:F:f:hi:LlMm:NnO:o:Pp:Ss:tT:Uv:w:X")) != -1)
 		switch (ch) {
 		case 'a':
 			argappend(&newfs_arg, "-a %s", optarg);
@@ -218,6 +218,9 @@ main(int argc, char **argv)
 		case 't':
 			argappend(&newfs_arg, "-t");
 			break;
+		case 'T':
+			argappend(&mount_arg, "-t %s", optarg);
+			break;
 		case 'U':
 			softdep = true;
 			break;