From d9f4f71916c1b42ab651cf1f8bb8c9c1f01198d4 Mon Sep 17 00:00:00 2001
From: Thomas Veerman <thomas@minix3.org>
Date: Thu, 22 Nov 2012 22:00:00 +0000
Subject: [PATCH] Implement dynamic mtab support

With this patch /etc/mtab becomes obsolete.
---
 commands/mount/mount.c         |  60 ++---------------
 commands/printroot/printroot.c |   4 --
 commands/umount/umount.c       |  54 +++++----------
 common/include/sys/mount.h     |   2 +
 etc/Makefile                   |   3 +-
 etc/rc                         |   1 -
 etc/usr/rc                     |   2 +-
 include/minix/minlib.h         |   7 +-
 include/minix/sysinfo.h        |   1 +
 lib/libcompat_minix/mtab.c     | 119 ++++++---------------------------
 servers/procfs/Makefile        |   2 +-
 servers/procfs/mounts.c        |  34 ++++++++++
 servers/procfs/mounts.h        |   6 ++
 servers/procfs/root.c          |   2 +
 servers/vfs/main.c             |   3 +-
 servers/vfs/misc.c             |   4 ++
 servers/vfs/mount.c            |  23 ++++---
 servers/vfs/proto.h            |   4 +-
 servers/vfs/vmnt.h             |   5 ++
 usr.sbin/mkfs.mfs/mkfs.c       |  48 ++++++-------
 20 files changed, 143 insertions(+), 241 deletions(-)
 create mode 100644 servers/procfs/mounts.c
 create mode 100644 servers/procfs/mounts.h

diff --git a/commands/mount/mount.c b/commands/mount/mount.c
index a9adecf19..f4e463cad 100644
--- a/commands/mount/mount.c
+++ b/commands/mount/mount.c
@@ -82,70 +82,23 @@ char *argv[];
 	return(EXIT_FAILURE);
   }
 
-  /* The mount has completed successfully. Tell the user. */
-  printf("%s is read-%s mounted on %s\n",
-	argv[1], mountflags & MS_RDONLY ? "only" : "write", argv[2]);
-  
-  /* Update /etc/mtab. */
-  update_mtab(argv[1], argv[2], type, mountflags);
+  printf("%s is mounted on %s\n", argv[1], argv[2]);
   return(EXIT_SUCCESS);
 }
 
-void
-update_mtab(char *dev, char *mountpoint, char *fstype, int mountflags)
-{
-	int n;
-	char *vs;
-	char special[PATH_MAX], mounted_on[PATH_MAX], version[10], rw_flag[10];
-
-	if (!write_mtab) return;
-	n = load_mtab("mount");
-	if (n < 0) exit(1);		/* something is wrong. */
-
-	/* Loop on all the /etc/mtab entries, copying each one to the output
-	 * buf. */
-	while (1) {
-		n = get_mtab_entry(special, mounted_on, version, rw_flag);
-		if (n < 0) break;
-		n = put_mtab_entry(special, mounted_on, version, rw_flag);
-		if (n < 0) {
-			std_err("mount: /etc/mtab has grown too large\n");
-			exit(1);
-		}
-	}
-	/* For MFS, use a version number. Otherwise, use the FS type name. */
-	if (!strcmp(fstype, MINIX_FS_TYPE)) {
-		vs = "MFSv3";
-	} else if (strlen(fstype) < sizeof(version)) {
-		vs = fstype;
-	} else {
-		vs = "-";
-	}
-	n = put_mtab_entry(dev, mountpoint, vs,
-			     (mountflags & MS_RDONLY ? "ro" : "rw") );
-	if (n < 0) {
-		std_err("mount: /etc/mtab has grown too large\n");
-		exit(1);
-	}
-
-	n = rewrite_mtab("mount");
-}
-
 void list()
 {
   int n;
-  char special[PATH_MAX], mounted_on[PATH_MAX], version[10], rw_flag[10];
+  char dev[PATH_MAX], mountpoint[PATH_MAX], type[MNTNAMELEN], flags[MNTFLAGLEN];
 
   /* Read and print /etc/mtab. */
   n = load_mtab("mount");
   if (n < 0) exit(1);
 
   while (1) {
-	n = get_mtab_entry(special, mounted_on, version, rw_flag);
+	n = get_mtab_entry(dev, mountpoint, type, flags);
 	if  (n < 0) break;
-	printf("%s is read-%s mounted on %s (type %s)\n",
-		special, strcmp(rw_flag, "rw") == 0 ? "write" : "only",
-		mounted_on, version);
+	printf("%s on %s type %s (%s)\n", dev, mountpoint, type, flags);
   }
   exit(0);
 }
@@ -200,10 +153,7 @@ mount_all()
 			device = NULL;
 
 		if (mount(device, mountpoint, mountflags, fs->fs_vfstype,
-			fs->fs_mntops) == 0) {
-			update_mtab(fs->fs_spec, fs->fs_file, fs->fs_vfstype,
-					mountflags);
-		} else {
+		    fs->fs_mntops) != 0) {
 			err = strerror(errno);
 			fprintf(stderr, "mount: Can't mount %s on %s: %s\n",
 				fs->fs_spec, fs->fs_file, err);
diff --git a/commands/printroot/printroot.c b/commands/printroot/printroot.c
index ad93c696b..c6afd4efc 100644
--- a/commands/printroot/printroot.c
+++ b/commands/printroot/printroot.c
@@ -2,10 +2,6 @@
 
 /* This program figures out what the root device is by doing a stat on it, and
  * then searching /dev until it finds an entry with the same device number.
- * A typical use (probably the only use) is in /etc/rc for initializing
- * /etc/mtab, as follows:
- *
- *	/usr/bin/printroot >/etc/mtab
  *
  *  9 Dec 1989	- clean up for 1.5 - full prototypes (BDE)
  * 15 Oct 1989	- avoid ACK cc bugs (BDE):
diff --git a/commands/umount/umount.c b/commands/umount/umount.c
index 9234f6201..b65921631 100644
--- a/commands/umount/umount.c
+++ b/commands/umount/umount.c
@@ -22,22 +22,22 @@ int find_mtab_entry(char *name);
 void update_mtab(void);
 void usage(void);
 
-static char device[PATH_MAX+1], mountpoint[PATH_MAX+1], vs[10], rw[10];
+static char device[PATH_MAX], mount_point[PATH_MAX], type[MNTNAMELEN],
+		flags[MNTFLAGLEN];
 
 int main(argc, argv)
 int argc;
 char *argv[];
 {
   int found;
-  int flags = 0UL;
-  int i;
+  int umount_flags = 0UL;
   char c;
   char *name;
 
   while ((c = getopt (argc, argv, "e")) != -1)
   {
 	switch (c) {
-		case 'e': flags |= MS_EXISTING; break;
+		case 'e': umount_flags |= MS_EXISTING; break;
 		default: break;
 	}
   }
@@ -48,11 +48,9 @@ char *argv[];
 
   name = argv[optind];
  
-
   found = find_mtab_entry(name);
 
-
-  if (umount2(name, flags) < 0) {
+  if (umount2(name, umount_flags) < 0) {
 	if (errno == EINVAL)
 		std_err("umount: Device not mounted\n");
 	else if (errno == ENOTBLK)
@@ -62,10 +60,8 @@ char *argv[];
 	exit(1);
   }
   if (found) {
-	printf("%s unmounted from %s\n", device, mountpoint);
-	update_mtab();
+	printf("%s unmounted from %s\n", device, mount_point);
   }
-  else printf("%s unmounted (mtab not updated)\n", name);
   return(0);
 }
 
@@ -76,7 +72,8 @@ char *name;
  * and generate a new mtab file without this entry on the fly. Do not write
  * out the result yet. Return whether we found a matching entry.
  */
-  char special[PATH_MAX+1], mounted_on[PATH_MAX+1], version[10], rw_flag[10];
+  char e_dev[PATH_MAX], e_mount_point[PATH_MAX], e_type[MNTNAMELEN],
+	e_flags[MNTFLAGLEN];
   struct stat nstat, mstat;
   int n, found;
 
@@ -86,44 +83,23 @@ char *name;
 
   found = 0;
   while (1) {
-	n = get_mtab_entry(special, mounted_on, version, rw_flag);
+	n = get_mtab_entry(e_dev, e_mount_point, e_type, e_flags);
 	if (n < 0) break;
-	if (strcmp(name, special) == 0 || (stat(mounted_on, &mstat) == 0 &&
+	if (strcmp(name, e_dev) == 0 || (stat(e_mount_point, &mstat) == 0 &&
 		mstat.st_dev == nstat.st_dev && mstat.st_ino == nstat.st_ino))
 	{
-		/* If we found an earlier match, keep that one. Mountpoints
-		 * may be stacked on top of each other, and unmounting should
-		 * take place in the reverse order of mounting.
-		 */
-		if (found) {
-			(void) put_mtab_entry(device, mountpoint, vs, rw);
-		}
-
-		strcpy(device, special);
-		strcpy(mountpoint, mounted_on);
-		strcpy(vs, version);
-		strcpy(rw, rw_flag);
+		strlcpy(device, e_dev, PATH_MAX);
+		strlcpy(mount_point, e_mount_point, PATH_MAX);
+		strlcpy(type, e_type, MNTNAMELEN);
+		strlcpy(flags, e_flags, MNTFLAGLEN);
 		found = 1;
-		continue;
+		break;
 	}
-	(void) put_mtab_entry(special, mounted_on, version, rw_flag);
   }
 
   return found;
 }
 
-void update_mtab()
-{
-/* Write out the new mtab file. */
-  int n;
-
-  n = rewrite_mtab("umount");
-  if (n < 0) {
-	std_err("/etc/mtab not updated.\n");
-	exit(1);
-  }
-}
-
 void usage()
 {
   std_err("Usage: umount [-e] name\n");
diff --git a/common/include/sys/mount.h b/common/include/sys/mount.h
index 606fff1e9..f4fbd7344 100644
--- a/common/include/sys/mount.h
+++ b/common/include/sys/mount.h
@@ -9,6 +9,8 @@
 #define MS_REUSE	0x002	/* Tell RS to try reusing binary from memory */
 #define MS_LABEL16	0x004	/* Mount message points to 16-byte label */
 #define MS_EXISTING	0x008	/* Tell mount to use already running server */
+#define MNTNAMELEN	16	/* Length of fs type name including nul */
+#define MNTFLAGLEN	64	/* Length of flags string including nul */
 
 int mount(char *_spec, char *_name, int _mountflags, char *type, char
 	*args);
diff --git a/etc/Makefile b/etc/Makefile
index 9cd11e6c6..98e2b56f4 100644
--- a/etc/Makefile
+++ b/etc/Makefile
@@ -309,7 +309,8 @@ CONFIGSYMLINKS+=	\
 			/usr/tmp		/var/tmp \
 			/usr/pkg/bin/clang	/usr/bin/cc \
 			/usr/pkg/bin/strip	/usr/bin/strip \
-			/dev/kbdaux		/dev/mouse
+			/dev/kbdaux		/dev/mouse \
+			/proc/mounts		/etc/mtab
 
 .endif # !defined(__MINIX)
 
diff --git a/etc/rc b/etc/rc
index 597fa0948..e78209f76 100755
--- a/etc/rc
+++ b/etc/rc
@@ -118,7 +118,6 @@ start)
     readclock || intr date -q
 
     # Initialize files.
-    printroot >/etc/mtab		# /etc/mtab keeps track of mounts
     >/etc/utmp				# /etc/utmp keeps track of logins
 
     # Use MFS binary only from kernel image?
diff --git a/etc/usr/rc b/etc/usr/rc
index 923758c48..523ac9122 100644
--- a/etc/usr/rc
+++ b/etc/usr/rc
@@ -212,7 +212,7 @@ start)
 ;;
 stop|down)
     	# Save random data, if /usr is mounted rw.
-	if grep ' \/usr .*rw' /etc/mtab >/dev/null
+	if grep ' \/usr .*rw.*' /etc/mtab >/dev/null
 	then
 	  if dd if=/dev/random of=$RANDOM_FILE.new bs=1024 count=1 2>/dev/null
     	  then
diff --git a/include/minix/minlib.h b/include/minix/minlib.h
index 1a65f8e1f..6a10450c2 100644
--- a/include/minix/minlib.h
+++ b/include/minix/minlib.h
@@ -1,6 +1,8 @@
 #ifndef _MINLIB
 #define _MINLIB
 
+#include <sys/mount.h>
+
 /* Miscellaneous BSD. */
 char *itoa(int _n);
 #ifndef __NBSD_LIBC
@@ -17,9 +19,8 @@ int fsversion(char *_dev, char *_prog);
 int getprocessor(void);
 void _cpuid(u32_t *eax, u32_t *ebx, u32_t *ecx, u32_t *edx);
 int load_mtab(char *_prog_name);
-int rewrite_mtab(char *_prog_name);
-int get_mtab_entry(char *_s1, char *_s2, char *_s3, char *_s4);
-int put_mtab_entry(char *_s1, char *_s2, char *_s3, char *_s4);
+int get_mtab_entry(char dev[PATH_MAX], char mount_point[PATH_MAX],
+			char type[MNTNAMELEN], char flags[MNTFLAGLEN]);
 
 /* read_tsc() and friends */
 void read_tsc(u32_t *hi, u32_t *lo);
diff --git a/include/minix/sysinfo.h b/include/minix/sysinfo.h
index e63bb006e..88f9d6fcf 100644
--- a/include/minix/sysinfo.h
+++ b/include/minix/sysinfo.h
@@ -13,6 +13,7 @@ int getsysinfo(endpoint_t who, int what, void *where, size_t size);
 #define SI_DATA_STORE	   5	/* get copy of data store mappings */
 #define SI_CALL_STATS	   9	/* system call statistics */
 #define SI_PROCPUB_TAB	   11	/* copy of public entries of process table */
+#define SI_VMNT_TAB        12   /* get vmnt table */
 
 #endif
 
diff --git a/lib/libcompat_minix/mtab.c b/lib/libcompat_minix/mtab.c
index c40a597bd..a38dde4df 100644
--- a/lib/libcompat_minix/mtab.c
+++ b/lib/libcompat_minix/mtab.c
@@ -23,13 +23,11 @@
  *
  *	load_mtab(&prog_name)		   - read /etc/mtab into mtab_in
  *	get_mtab_entry(&s1, &s2, &s3, &s4) - arrays that are filled in
- *	put_mtab_entry(&s1, &s2, &s3, &s4) - append a line to mtab_out
- *	rewrite_mtab(&prog_name)	   - write mtab_out to /etc/mtab
  *
- * If load_mtab and rewrite_mtab work, they return 0.  If they fail, they
- * print their own error messages on stderr and return -1.  When get_mtab_entry
+ * If load_mtab works, it returns 0.  If it fails, it prints its own error
+ * message on stderr and returns -1.  When get_mtab_entry
  * runs out of entries to return, it sets the first pointer to NULL and returns
- * -1 instead of 0.  Also, rewrite_mtab returns -1 if it fails.
+ * -1 instead of 0.
  */
  
 #include <sys/types.h>
@@ -46,16 +44,11 @@
 
 char *etc_mtab = "/etc/mtab";	  /* name of the /etc/mtab file */
 static char mtab_in[BUF_SIZE+1];  /* holds /etc/mtab when it is read in */
-static char mtab_out[BUF_SIZE+1]; /* buf to build /etc/mtab for output later */
 static char *iptr = mtab_in;	  /* pointer to next line to feed out. */
-static char *optr = mtab_out;	  /* pointer to place where next line goes */
 
 int load_mtab(char *prog_name );
-int rewrite_mtab(char *prog_name );
-int get_mtab_entry(char *special, char *mounted_on, char *version, char
-	*rw_flag);
-int put_mtab_entry(char *special, char *mounted_on, char *version, char
-	*rw_flag);
+int get_mtab_entry(char dev[PATH_MAX], char mount_point[PATH_MAX],
+	char type[MNTNAMELEN], char flags[MNTFLAGLEN]);
 static void err(char *prog_name, char *str );
 
 
@@ -91,110 +84,36 @@ char *prog_name;
 
   close(fd);
 
-  /* Replace all the whitespace by '\0'. */
   ptr = mtab_in;
-  while (*ptr != '\0') {
-	if (isspace(*ptr)) *ptr = '\0';
-	ptr++;
-  }
-  return(0);
-}
-
-
-int rewrite_mtab(prog_name)
-char *prog_name;
-{
-/* Write mtab_out to /etc/mtab. */
-
-  int fd, n;
 
-  /* Do a creat to truncate the file. */
-  fd = creat(etc_mtab, 0777);
-  if (fd < 0) {
-	err(prog_name, ": cannot overwrite ");
-	return(-1);
-  }
-
-  /* File created.  Write it. */
-  n = write(fd, mtab_out, (unsigned int)(optr - mtab_out));
-  if (n <= 0) {
-	/* Write failed. */
-	err(prog_name, " could not write ");
-	return(-1);
-  }
-
-  close(fd);
   return(0);
 }
 
-
-int get_mtab_entry(special, mounted_on, version, rw_flag)
-char *special;
-char *mounted_on;
-char *version;
-char *rw_flag;
+int get_mtab_entry(char dev[PATH_MAX], char mount_point[PATH_MAX],
+			char type[MNTNAMELEN], char flags[MNTFLAGLEN])
 {
 /* Return the next entry from mtab_in. */
 
+  int r;
+
   if (iptr >= &mtab_in[BUF_SIZE]) {
-	special[0] = '\0';
+	dev[0] = '\0';
 	return(-1);
   }
 
-  strcpy(special, iptr);
-  while (isprint(*iptr)) iptr++;
-  while (*iptr == '\0'&& iptr < &mtab_in[BUF_SIZE]) iptr++;
-
-  strcpy(mounted_on, iptr);
-  while (isprint(*iptr)) iptr++;
-  while (*iptr == '\0'&& iptr < &mtab_in[BUF_SIZE]) iptr++;
-
-  strcpy(version, iptr);
-  while (isprint(*iptr)) iptr++;
-  while (*iptr == '\0'&& iptr < &mtab_in[BUF_SIZE]) iptr++;
-
-  strcpy(rw_flag, iptr);
-  while (isprint(*iptr)) iptr++;
-  while (*iptr == '\0'&& iptr < &mtab_in[BUF_SIZE]) iptr++;
-  return(0);
-}
-
-
-int put_mtab_entry(special, mounted_on, version, rw_flag)
-char *special;
-char *mounted_on;
-char *version;
-char *rw_flag;
-{
-/* Append an entry to the mtab_out buffer. */
-
-  int n1, n2, n3, n4;
-
-  n1 = strlen(special);
-  n2 = strlen(mounted_on);
-  n3 = strlen(version);
-  n4 = strlen(rw_flag);
-
-  if (optr + n1 + n2 + n3 + n4 + 5 >= &mtab_out[BUF_SIZE]) return(-1);
-  strcpy(optr, special);
-  optr += n1;
-  *optr++ = ' ';
-
-  strcpy(optr, mounted_on);
-  optr += n2;
-  *optr++ = ' ';
-
-  strcpy(optr, version);
-  optr += n3;
-  *optr++ = ' ';
+  r = sscanf(iptr, "%s on %s type %s (%[^)]s\n",
+		dev, mount_point, type, flags);
+  if (r != 4) {
+	dev[0] = '\0';
+	return(-1);
+  }
 
-  strcpy(optr, rw_flag);
-  optr += n4;
-  *optr++ = '\n';
+  iptr = strchr(iptr, '\n');	/* Find end of line */
+  if (iptr != NULL) iptr++; 	/* Move to next line */
   return(0);
+  
 }
 
-
 static void
 err(prog_name, str)
 char *prog_name, *str;
diff --git a/servers/procfs/Makefile b/servers/procfs/Makefile
index 2697b6e0b..228425121 100644
--- a/servers/procfs/Makefile
+++ b/servers/procfs/Makefile
@@ -4,7 +4,7 @@
 .include <bsd.own.mk>
 
 PROG=	procfs
-SRCS=	buf.c main.c pid.c root.c tree.c util.c cpuinfo.c
+SRCS=	buf.c main.c pid.c root.c tree.c util.c cpuinfo.c mounts.c
 
 CPPFLAGS+= -I${NETBSDSRCDIR} -I${NETBSDSRCDIR}/servers
 
diff --git a/servers/procfs/mounts.c b/servers/procfs/mounts.c
new file mode 100644
index 000000000..cfd4f2663
--- /dev/null
+++ b/servers/procfs/mounts.c
@@ -0,0 +1,34 @@
+#include "inc.h"
+#include "vfs/vmnt.h"
+
+extern struct mproc mproc[NR_PROCS];
+
+/*===========================================================================*
+ *                              root_mtab                                    *
+ *===========================================================================*/
+void
+root_mounts(void)
+{
+	struct vmnt vmnt[NR_MNTS];
+	struct vmnt *vmp;
+	struct mproc *rmp;
+        int slot;
+
+        if (getsysinfo(VFS_PROC_NR, SI_VMNT_TAB, vmnt, sizeof(vmnt)) != OK)
+                return;
+
+        for (vmp = &vmnt[0]; vmp < &vmnt[NR_MNTS]; vmp++) {
+                if (vmp->m_dev == NO_DEV)
+                        continue;
+		if (vmp->m_fs_e == PFS_PROC_NR)
+			continue; /* Skip (special case) */
+
+		slot = _ENDPOINT_P(vmp->m_fs_e);
+		if (slot < 0 || slot >= NR_PROCS)
+			continue;
+		rmp = &mproc[slot];
+                buf_printf("%s on %s type %s (%s)\n", vmp->m_mount_dev,
+			vmp->m_mount_path, rmp->mp_name,
+			(vmp->m_flags & VMNT_READONLY) ? "ro" : "rw");
+        }
+}
diff --git a/servers/procfs/mounts.h b/servers/procfs/mounts.h
new file mode 100644
index 000000000..ca5712b4b
--- /dev/null
+++ b/servers/procfs/mounts.h
@@ -0,0 +1,6 @@
+#ifndef __PROCFS_MOUNTS_H
+#define __PROCFS_MOUNTS_H__
+
+void root_mounts(void);
+
+#endif /* __PROCFS_MOUNTS_H__ */
diff --git a/servers/procfs/root.c b/servers/procfs/root.c
index 44ee10539..dfd5b20e9 100644
--- a/servers/procfs/root.c
+++ b/servers/procfs/root.c
@@ -4,6 +4,7 @@
 #include <machine/pci.h>
 #include <minix/dmap.h>
 #include "cpuinfo.h"
+#include "mounts.h"
 
 static void root_hz(void);
 static void root_uptime(void);
@@ -24,6 +25,7 @@ struct file root_files[] = {
 	{ "dmap",	REG_ALL_MODE,	(data_t) root_dmap	},
 	{ "cpuinfo",	REG_ALL_MODE,	(data_t) root_cpuinfo	},
 	{ "ipcvecs",	REG_ALL_MODE,	(data_t) root_ipcvecs	},
+	{ "mounts",	REG_ALL_MODE,	(data_t) root_mounts	},
 	{ NULL,		0,		NULL			}
 };
 
diff --git a/servers/vfs/main.c b/servers/vfs/main.c
index adece2af8..249fb5259 100644
--- a/servers/vfs/main.c
+++ b/servers/vfs/main.c
@@ -621,7 +621,8 @@ static void *do_init_root(void *arg)
   }
 
   receive_from = MFS_PROC_NR;
-  if ((r = mount_fs(DEV_IMGRD, "/", MFS_PROC_NR, 0, mount_label)) != OK)
+  r = mount_fs(DEV_IMGRD, "bootramdisk", "/", MFS_PROC_NR, 0, mount_label);
+  if (r != OK)
 	panic("Failed to initialize root");
   receive_from = ANY;
 
diff --git a/servers/vfs/misc.c b/servers/vfs/misc.c
index cd7319f46..4c15d1249 100644
--- a/servers/vfs/misc.c
+++ b/servers/vfs/misc.c
@@ -91,6 +91,10 @@ int do_getsysinfo()
 	len = sizeof(calls_stats);
 	break;
 #endif
+    case SI_VMNT_TAB:
+	src_addr = (vir_bytes) vmnt;
+	len = sizeof(struct vmnt) * NR_MNTS;
+	break;
     default:
 	return(EINVAL);
   }
diff --git a/servers/vfs/mount.c b/servers/vfs/mount.c
index 7b14b865b..e9354bb30 100644
--- a/servers/vfs/mount.c
+++ b/servers/vfs/mount.c
@@ -100,7 +100,7 @@ int do_mount()
 /* Perform the mount(name, mfile, mount_flags) system call. */
   endpoint_t fs_e;
   int r, slot, rdonly, nodev;
-  char fullpath[PATH_MAX];
+  char mount_path[PATH_MAX], mount_dev[PATH_MAX];
   char mount_label[LABEL_MAX];
   dev_t dev;
   int mflags;
@@ -145,21 +145,22 @@ int do_mount()
   nodev = (vname1_length == 0);
   if (!nodev) {
 	/* If 'name' is not for a block special file, return error. */
-	if (fetch_name(vname1, vname1_length, fullpath) != OK)
+	if (fetch_name(vname1, vname1_length, mount_dev) != OK)
 		return(err_code);
-	if ((dev = name_to_dev(FALSE /*allow_mountpt*/, fullpath)) == NO_DEV)
+	if ((dev = name_to_dev(FALSE /*allow_mountpt*/, mount_dev)) == NO_DEV)
 		return(err_code);
   } else {
 	/* Find a free pseudo-device as substitute for an actual device. */
 	if ((dev = find_free_nonedev()) == NO_DEV)
 		return(err_code);
+	strlcpy(mount_dev, "none", sizeof(mount_dev));
   }
 
   /* Fetch the name of the mountpoint */
-  if (fetch_name(vname2, vname2_length, fullpath) != OK) return(err_code);
+  if (fetch_name(vname2, vname2_length, mount_path) != OK) return(err_code);
 
   /* Do the actual job */
-  return mount_fs(dev, fullpath, fs_e, rdonly, mount_label);
+  return mount_fs(dev, mount_dev, mount_path, fs_e, rdonly, mount_label);
 }
 
 
@@ -168,7 +169,8 @@ int do_mount()
  *===========================================================================*/
 int mount_fs(
 dev_t dev,
-char mountpoint[PATH_MAX],
+char mount_dev[PATH_MAX],
+char mount_path[PATH_MAX],
 endpoint_t fs_e,
 int rdonly,
 char mount_label[LABEL_MAX] )
@@ -206,10 +208,11 @@ char mount_label[LABEL_MAX] )
   } else if ((new_vmp = get_free_vmnt()) == NULL) {
 	return(ENOMEM);
   }
-
   if ((r = lock_vmnt(new_vmp, VMNT_EXCL)) != OK) return(r);
 
-  isroot = (strcmp(mountpoint, "/") == 0);
+  strlcpy(new_vmp->m_mount_path, mount_path, PATH_MAX);
+  strlcpy(new_vmp->m_mount_dev, mount_dev, PATH_MAX);
+  isroot = (strcmp(mount_path, "/") == 0);
   mount_root = (isroot && have_root < 2); /* Root can be mounted twice:
 					   * 1: ramdisk
 					   * 2: boot disk (e.g., harddisk)
@@ -217,7 +220,7 @@ char mount_label[LABEL_MAX] )
 
   if (!mount_root) {
 	/* Get vnode of mountpoint */
-	lookup_init(&resolve, mountpoint, PATH_NOFLAGS, &parent_vmp, &vp);
+	lookup_init(&resolve, mount_path, PATH_NOFLAGS, &parent_vmp, &vp);
 	resolve.l_vmnt_lock = VMNT_EXCL;
 	resolve.l_vnode_lock = VNODE_WRITE;
 	if ((vp = eat_path(&resolve, fp)) == NULL)
@@ -405,6 +408,8 @@ void mount_pfs(void)
   vmp->m_dev = dev;
   vmp->m_fs_e = PFS_PROC_NR;
   strlcpy(vmp->m_label, "pfs", LABEL_MAX);
+  strlcpy(vmp->m_mount_path, "pipe", PATH_MAX);
+  strlcpy(vmp->m_mount_dev, "none", PATH_MAX);
 
   rfp = &fproc[_ENDPOINT_P(PFS_PROC_NR)];
 }
diff --git a/servers/vfs/proto.h b/servers/vfs/proto.h
index 281200514..1b528b7fa 100644
--- a/servers/vfs/proto.h
+++ b/servers/vfs/proto.h
@@ -151,8 +151,8 @@ int do_mount(void);
 int do_umount(void);
 int is_nonedev(dev_t dev);
 void mount_pfs(void);
-int mount_fs(dev_t dev, char fullpath[PATH_MAX+1], endpoint_t fs_e, int
-	rdonly, char mount_label[LABEL_MAX]);
+int mount_fs(dev_t dev, char mount_dev[PATH_MAX], char mount_path[PATH_MAX],
+	endpoint_t fs_e, int rdonly, char mount_label[LABEL_MAX]);
 int unmount(dev_t dev, char label[LABEL_MAX]);
 void unmount_all(int force);
 
diff --git a/servers/vfs/vmnt.h b/servers/vfs/vmnt.h
index 14d00b3ab..2d3156e5f 100644
--- a/servers/vfs/vmnt.h
+++ b/servers/vfs/vmnt.h
@@ -1,6 +1,9 @@
 #ifndef __VFS_VMNT_H__
 #define __VFS_VMNT_H__
 
+#include "tll.h"
+#include "comm.h"
+
 EXTERN struct vmnt {
   int m_fs_e;			/* FS process' kernel endpoint */
   tll_t m_lock;
@@ -10,6 +13,8 @@ EXTERN struct vmnt {
   struct vnode *m_mounted_on;	/* vnode on which the partition is mounted */
   struct vnode *m_root_node;	/* root vnode */
   char m_label[LABEL_MAX];	/* label of the file system process */
+  char m_mount_path[PATH_MAX];	/* path on which vmnt is mounted */
+  char m_mount_dev[PATH_MAX];	/* path on which vmnt is mounted */
 } vmnt[NR_MNTS];
 
 /* vmnt flags */
diff --git a/usr.sbin/mkfs.mfs/mkfs.c b/usr.sbin/mkfs.mfs/mkfs.c
index d8c220338..8cb7be90b 100644
--- a/usr.sbin/mkfs.mfs/mkfs.c
+++ b/usr.sbin/mkfs.mfs/mkfs.c
@@ -94,9 +94,12 @@ int main(int argc, char **argv);
 block_t sizeup(char *device);
 void super(zone_t zones, ino_t inodes);
 void rootdir(ino_t inode);
+int dir_try_enter(zone_t z, ino_t child, char *name);
 void eat_dir(ino_t parent);
 void eat_file(ino_t inode, int f);
-void enter_dir(ino_t parent, char *name, ino_t child);
+void enter_dir(ino_t parent, char const *name, ino_t child);
+void enter_symlink(ino_t inode, char *link);
+d2_inode *get_inoblock(ino_t i, block_t *blockno, d2_inode **ino);
 void incr_size(ino_t n, size_t count);
 static ino_t alloc_inode(int mode, int usrid, int grpid);
 static zone_t alloc_zone(void);
@@ -109,7 +112,7 @@ int mode_con(char *p);
 void getline(char line[LINE_LEN], char *parse[MAX_TOKENS]);
 void check_mtab(char *devname);
 uint32_t file_time(int f);
-void pexit(char *s);
+__dead void pexit(char const *s);
 void copy(char *from, char *to, size_t count);
 void print_fs(void);
 int read_and_set(block_t n);
@@ -120,7 +123,7 @@ void put_block(block_t n, char *buf);
 void mx_read(int blocknr, char *buf);
 void mx_write(int blocknr, char *buf);
 void dexit(char *s, int sectnum, int err);
-void usage(void);
+__dead void usage(void);
 void *alloc_block(void);
 
 ino_t inocount;
@@ -511,14 +514,13 @@ char *device;
 /*
  * copied from fslib
  */
-static int bitmapsize(nr_bits, block_size)
-uint32_t nr_bits;
-size_t block_size;
+static int bitmapsize(uint32_t nr_bits, size_t blk_size)
 {
   block_t nr_blocks;
 
-  nr_blocks = (int) (nr_bits / FS_BITS_PER_BLOCK(block_size));
-  if (((uint32_t) nr_blocks * FS_BITS_PER_BLOCK(block_size)) < nr_bits) ++nr_blocks;
+  nr_blocks = (int) (nr_bits / FS_BITS_PER_BLOCK(blk_size));
+  if (((uint32_t) nr_blocks * FS_BITS_PER_BLOCK(blk_size)) < nr_bits)
+	++nr_blocks;
   return(nr_blocks);
 }
 
@@ -788,9 +790,7 @@ int dir_try_enter(zone_t z, ino_t child, char *name)
 /*================================================================
  *	    directory & inode management assist group
  *===============================================================*/
-void enter_dir(parent, name, child)
-ino_t parent, child;
-char *name;
+void enter_dir(ino_t parent, char const *name, ino_t child)
 {
   /* Enter child in parent directory */
   /* Works for dir > 1 block and zone > block */
@@ -810,7 +810,7 @@ char *name;
 		ino->d2_zone[k] = z;
 	}
 
-	if(dir_try_enter(z, child, name)) {
+	if(dir_try_enter(z, child, __UNCONST(name))) {
 		put_block(b, (char *) inoblock);
 		free(inoblock);
 		free(indirblock);
@@ -828,7 +828,7 @@ char *name;
   	z = indirblock[k];
 	if(!z) z = indirblock[k] = alloc_zone();
 
-	if(dir_try_enter(z, child, name)) {
+	if(dir_try_enter(z, child, __UNCONST(name))) {
 		put_block(b, (char *) inoblock);
 		put_block(ino->d2_zone[V2_NR_DZONES], (char *) indirblock);
 		free(inoblock);
@@ -908,10 +908,10 @@ ino_t n;
   off = (n - 1) % inodes_per_block;
   {
 	static d2_inode *inode2 = NULL;
-	int n;
+	int s;
 
-	n = sizeof(*inode2) * V2_INODES_PER_BLOCK(block_size);
-	if(!inode2 && !(inode2 = malloc(n)))
+	s = sizeof(*inode2) * V2_INODES_PER_BLOCK(block_size);
+	if(!inode2 && !(inode2 = malloc(s)))
 		pexit("couldn't allocate a block of inodes");
 
 	get_block(b, (char *) inode2);
@@ -1119,7 +1119,8 @@ char *device;			/* /dev/hd1 or whatever */
 #if defined(__minix)
   int n, r;
   struct stat sb;
-  char special[PATH_MAX + 1], mounted_on[PATH_MAX + 1], version[10], rw_flag[10];
+  char dev[PATH_MAX], mount_point[PATH_MAX],
+	type[MNTNAMELEN], flags[MNTFLAGLEN];
 
   r= stat(device, &sb);
   if (r == -1)
@@ -1136,14 +1137,14 @@ char *device;			/* /dev/hd1 or whatever */
 	return;
   }
 
-  if (load_mtab("mkfs") < 0) return;
+  if (load_mtab(__UNCONST("mkfs")) < 0) return;
   while (1) {
-	n = get_mtab_entry(special, mounted_on, version, rw_flag);
+	n = get_mtab_entry(dev, mount_point, type, flags);
 	if (n < 0) return;
-	if (strcmp(device, special) == 0) {
+	if (strcmp(device, dev) == 0) {
 		/* Can't mkfs on top of a mounted file system. */
 		fprintf(stderr, "%s: %s is mounted on %s\n",
-			progname, device, mounted_on);
+			progname, device, mount_point);
 		exit(1);
 	}
   }
@@ -1266,8 +1267,7 @@ int f;
 }
 
 
-void pexit(s)
-char *s;
+__dead void pexit(char const * s)
 {
   fprintf(stderr, "%s: %s\n", progname, s);
   if (lct != 0)
@@ -1379,7 +1379,7 @@ block_t n;
   return(r);
 }
 
-void usage()
+__dead void usage()
 {
   fprintf(stderr,
 	  "Usage: %s [-12dlot] [-b blocks] [-i inodes]\n"
-- 
2.44.0