diff a70280308ae782ac422e78ccf19b221697116c1b uncommitted
--- a/sys/src/cmd/ext4srv/common.h
+++ b/sys/src/cmd/ext4srv/common.h
@@ -5,9 +5,7 @@
 	char *group;
 	int cachewb;
 	int asroot;
-	int rdonly;
-
-	int fstype;
+	int ream;
 	int blksz;
 	int inodesz;
 	u32int ninode;
--- a/sys/src/cmd/ext4srv/ext4srv.c
+++ b/sys/src/cmd/ext4srv/ext4srv.c
@@ -36,9 +36,8 @@
 	.group = nil,
 	.cachewb = 0,
 	.asroot = 0,
-	.rdonly = 0,
 
-	.fstype = -1,
+	.ream = 0,
 	.blksz = 1024,
 	.label = "",
 	.inodesz = 256,
@@ -46,7 +45,9 @@
 };
 static u32int Root;
 static u8int zero[65536];
-static char *srvname = "ext4";
+static char *srvname;
+static char *device;
+static Part *devpart;
 
 static int
 haveperm(Aux *a, int p, struct ext4_inode *inodeout)
@@ -115,27 +116,31 @@
 static void
 rattach(Req *r)
 {
-	char err[ERRMAX];
 	Aux *a;
 
 	if((a = calloc(1, sizeof(*a))) == nil)
 		respond(r, "memory");
-	else if((a->p = openpart(r->ifcall.aname, &opts)) == nil){
-		free(a);
-		rerrstr(err, sizeof(err));
-		respond(r, err);
-	}else{
-		if(opts.asroot || findgroup(&a->p->groups, r->ifcall.uname, &a->uid) == nil)
-			a->uid = Root;
-
-		incref(a->p);
-		a->type = Adir;
-		a->path = estrdup9p("");
-		r->ofcall.qid = a->p->qidmask;
-		r->fid->qid = a->p->qidmask;
-		r->fid->aux = a;
-		respond(r, nil);
+	if(r->ifcall.aname && *r->ifcall.aname){
+		if((a->p = openpart(r->ifcall.aname, &opts)) == nil){
+			free(a);
+			responderror(r);
+			return;
+		}
+	}else if((a->p = devpart) == nil){
+		respond(r, "no file specified");
+		return;
 	}
+
+	if(opts.asroot || findgroup(&a->p->groups, r->ifcall.uname, &a->uid) == nil)
+		a->uid = Root;
+
+	incref(a->p);
+	a->type = Adir;
+	a->path = estrdup9p("");
+	r->ofcall.qid = a->p->qidmask;
+	r->fid->qid = a->p->qidmask;
+	r->fid->aux = a;
+	respond(r, nil);
 }
 
 static u32int
@@ -876,8 +881,8 @@
 static void
 usage(void)
 {
-	fprint(2, "usage: %s [-Crs] [-g groupfile] [-R uid] [srvname]\n", argv0);
-	fprint(2, "mkfs:  %s -M (2|3|4) [-L label] [-b blksize] [-N numinodes] [-I inodesize] device\n", argv0);
+	fprint(2, "usage: %s [-Cs] [-f file] [-g groupfile] [-n srvname] [-R uid]\n", argv0);
+	fprint(2, "mkfs:  %s [-L label] [-b blksz] [-N ninodes] [-I inodesz] -f file -r (2|3|4)\n", argv0);
 	threadexitsall("usage");
 }
 
@@ -891,20 +896,22 @@
 	rfork(RFNOTEG);
 
 	stdio = 0;
+	device = nil;
 	ARGBEGIN{
+	case 'C':
+		opts.cachewb = 1;
+		break;
 	case 'D':
 		chatty9p++;
-nomkfs:
-		if(opts.fstype > 0)
-			usage();
-		opts.fstype = 0;
 		break;
 	case 'd':
 		ext4_dmask_set(strtoul(EARGF(usage()), nil, 0));
 		break;
-	case 'C':
-		opts.cachewb = 1;
-		goto nomkfs;
+	case 'f':
+		if(device != nil)
+			usage();
+		device = EARGF(usage());
+		break;
 	case 'g':
 		gr = EARGF(usage());
 		if((f = open(gr, OREAD)) < 0)
@@ -919,23 +926,20 @@
 			sysfatal("%s: read failed", gr);
 		close(f);
 		opts.group[sz] = 0;
-		goto nomkfs;
+		break;
+	case 'n':
+		if(stdio != 0)
+			usage();
+		srvname = EARGF(usage());
+		break;
 	case 'R':
 		opts.asroot = 1;
 		Root = atoll(EARGF(usage()));
-		goto nomkfs;
-	case 'r':
-		opts.rdonly = 1;
-		goto nomkfs;
+		break;
 	case 's':
 		stdio = 1;
-		goto nomkfs;
-	case 'M':
-		if(!opts.fstype)
+		if(srvname != nil)
 			usage();
-		opts.fstype = atoi(EARGF(usage()));
-		if(opts.fstype < 2 || opts.fstype > 4)
-			usage();
 		break;
 
 	case 'b':
@@ -942,47 +946,48 @@
 		opts.blksz = atoi(EARGF(usage()));
 		if(opts.blksz != 1024 && opts.blksz != 2048 && opts.blksz != 4096)
 			usage();
-yesmkfs:
-		if(opts.fstype < 1)
-			usage();
 		break;
-	case 'L':
-		opts.label = EARGF(usage());
-		goto yesmkfs;
 	case 'I':
 		opts.inodesz = atoi(EARGF(usage()));
 		if(opts.inodesz < 128 || ((opts.inodesz-1) & opts.inodesz) != 0)
 			usage();
-		goto yesmkfs;
+		break;
+	case 'L':
+		opts.label = EARGF(usage());
+		break;
 	case 'N':
 		opts.ninode = atoi(EARGF(usage()));
 		if(opts.ninode < 1)
 			usage();
-		goto yesmkfs;
+		break;
+	case 'r':
+		if(opts.ream > 0)
+			usage();
+		opts.ream = atoi(EARGF(usage()));
+		if(opts.ream < 2 || opts.ream > 4)
+			usage();
+		break;
 
 	default:
 		usage();
 	}ARGEND
 
-	if(opts.fstype > 1){
-		if(argc != 1)
-			usage();
-		if(openpart(argv[0], &opts) == nil)
-			sysfatal("%r");
-		closeallparts();
-		threadexitsall(nil);
-	}else{
-		if(!stdio && argc == 1)
-			srvname = *argv;
-		else if(argc != 0)
-			usage();
+	if(argc != 0)
+		usage();
 
-		if(stdio){
-			fs.infd = 0;
-			fs.outfd = 1;
-			threadsrv(&fs);
-		}else
-			threadpostsrv(&fs, srvname);
-		threadexits(nil);
+	if(device == nil && opts.ream > 1)
+		usage();
+	if(device != nil && (devpart = openpart(device, &opts)) == nil)
+		sysfatal("%r");
+
+	if(stdio){
+		fs.infd = 0;
+		fs.outfd = 1;
+		threadsrv(&fs);
+	}else{
+		if(srvname == nil)
+			srvname = "ext4";
+		threadpostsrv(&fs, srvname);
 	}
+	threadexits(nil);
 }
--- a/sys/src/cmd/ext4srv/part.c
+++ b/sys/src/cmd/ext4srv/part.c
@@ -203,7 +203,7 @@
 	int r;
 
 	mp = &p->mp;
-	if(ext4_mount(mp, &p->bdev, opts->rdonly) < 0){
+	if(ext4_mount(mp, &p->bdev, 0) < 0){
 		werrstr("mount: %r");
 		goto error;
 	}
@@ -307,7 +307,7 @@
 		p->partdev = (char*)(p+1) + blksz;
 		strcpy(p->partdev, dev);
 
-		if(opts->fstype > 1){
+		if(opts->ream > 1){
 			memset(&fs, 0, sizeof(fs));
 			memset(&info, 0, sizeof(info));
 			info.block_size = opts->blksz;
@@ -314,12 +314,12 @@
 			snprint(info.label, sizeof(info.label), opts->label);
 			info.inode_size = opts->inodesz;
 			info.inodes = opts->ninode;
-			info.journal = opts->fstype > 2;
+			info.journal = opts->ream > 2;
 			for(i = 0; i < 16; i += 4){
 				rn = truerand();
 				memcpy(info.uuid+i, &rn, 4);
 			}
-			if(ext4_mkfs(&fs, &p->bdev, &info, opts->fstype) < 0){
+			if(ext4_mkfs(&fs, &p->bdev, &info, opts->ream) < 0){
 				werrstr("mkfs: %r");
 				goto error;
 			}