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--- util-linux-2.13-pre6/mount/mount.8.subtree	2006-06-12 09:18:26.000000000 +0200
+++ util-linux-2.13-pre6/mount/mount.8	2006-06-12 09:19:43.000000000 +0200
@@ -131,6 +131,41 @@
 .B "mount --move olddir newdir"
 .RE
 
+Since Linux 2.6.15 it is possible to mark a mount and its submounts as shared,
+private, slave or unbindable. A shared mount provides ability to create mirrors
+of that mount such that mounts and umounts within any of the mirrors propagate
+to the other mirror. A slave mount receives propagation from its master, but
+any not vice-versa.  A private mount carries no propagation abilities.  A
+unbindable mount is a private mount which cannot cloned through a bind
+operation. Detailed semantics is documented in Documentation/sharedsubtree.txt
+file in the kernel source tree.
+.RS
+.br
+.B "mount --make-shared mountpoint"
+.br
+.B "mount --make-slave mountpoint"
+.br
+.B "mount --make-private mountpoint"
+.br
+.B "mount --make-unbindable mountpoint"
+.br
+.RE
+
+The following commands allows one to recursively change the type of all the
+mounts under a given mountpoint.
+.RS
+.br
+.B "mount --make-rshared mountpoint"
+.br
+.B "mount --make-rslave mountpoint"
+.br
+.B "mount --make-rprivate mountpoint"
+.br
+.B
+"mount --make-runbindable mountpoint"
+.br
+.RE
+
 The
 .I proc
 file system is not associated with a special device, and when
--- util-linux-2.13-pre6/mount/mount_constants.h.subtree	2002-11-01 01:24:36.000000000 +0100
+++ util-linux-2.13-pre6/mount/mount_constants.h	2006-06-12 09:19:43.000000000 +0200
@@ -57,6 +57,18 @@
 #ifndef MS_VERBOSE
 #define MS_VERBOSE	0x8000	/* 32768 */
 #endif
+#ifndef MS_UNBINDABLE
+#define MS_UNBINDABLE	(1<<17)	/* 131072 unbindable*/
+#endif
+#ifndef MS_PRIVATE
+#define MS_PRIVATE	(1<<18)	/* 262144 Private*/
+#endif
+#ifndef MS_SLAVE
+#define MS_SLAVE	(1<<19)	/* 524288 Slave*/
+#endif
+#ifndef MS_SHARED
+#define MS_SHARED	(1<<20)	/* 1048576 Shared*/
+#endif
 /*
  * Magic mount flag number. Had to be or-ed to the flag values.
  */
--- util-linux-2.13-pre6/mount/mount.c.subtree	2006-06-12 09:18:26.000000000 +0200
+++ util-linux-2.13-pre6/mount/mount.c	2006-06-12 09:19:43.000000000 +0200
@@ -74,7 +74,9 @@
 /* Add volumelabel in a listing of mounted devices (-l). */
 static int list_with_volumelabel = 0;
 
-/* Nonzero for mount {--bind|--replace|--before|--after|--over|--move} */
+/* Nonzero for mount {--bind|--replace|--before|--after|--over|--move|
+ * 		       make-shared|make-private|make-unbindable|make-slave}
+ */
 static int mounttype = 0;
 
 /* True if ruid != euid.  */
@@ -109,6 +111,8 @@
 /* Options that we keep from appearing in the options field in the mtab.  */
 #define MS_NOMTAB	(MS_REMOUNT|MS_NOAUTO|MS_USERS|MS_USER|MS_PAMCONSOLE)
 
+#define MS_PROPAGATION  (MS_SHARED|MS_SLAVE|MS_UNBINDABLE|MS_PRIVATE)
+
 /* Options that we make ordinary users have by default.  */
 #define MS_SECURE	(MS_NOEXEC|MS_NOSUID|MS_NODEV)
 
@@ -346,6 +350,9 @@
 		*flags |= MS_RDONLY;
 	if (readwrite)
 		*flags &= ~MS_RDONLY;
+
+	if (mounttype & MS_PROPAGATION)
+		*flags &= ~MS_BIND;
 	*flags |= mounttype;
 }
 
@@ -916,13 +923,15 @@
       if (loop)
 	  opt_loopdev = loopdev;
 
-      update_mtab_entry(loop ? loopfile : spec,
+      if (!(mounttype & MS_PROPAGATION)) {
+	      update_mtab_entry(loop ? loopfile : spec,
 			node,
 			types ? types : "unknown",
 			fix_opts_string (flags & ~MS_NOMTAB, extra_opts, user),
 			flags,
 			freq,
 			pass);
+      }
 
       block_signals (SIG_UNBLOCK);
       res = 0;
@@ -1461,6 +1470,14 @@
 	{ "move", 0, 0, 133 },
 	{ "guess-fstype", 1, 0, 134 },
 	{ "rbind", 0, 0, 135 },
+	{ "make-shared", 0, 0, 136 },
+	{ "make-slave", 0, 0, 137 },
+	{ "make-private", 0, 0, 138 },
+	{ "make-unbindable", 0, 0, 139 },
+	{ "make-rshared", 0, 0, 140 },
+	{ "make-rslave", 0, 0, 141 },
+	{ "make-rprivate", 0, 0, 142 },
+	{ "make-runbindable", 0, 0, 143 },
 	{ "internal-only", 0, 0, 'i' },
 	{ NULL, 0, 0, 0 }
 };
@@ -1487,6 +1504,17 @@
 	  "       mount --bind olddir newdir\n"
 	  "or move a subtree:\n"
 	  "       mount --move olddir newdir\n"
+	  "One can change the type of mount containing the directory dir:\n"
+	  "       mount --make-shared dir\n"
+	  "       mount --make-slave dir\n"
+	  "       mount --make-private dir\n"
+	  "       mount --make-unbindable dir\n"
+	  "One can change the type of all the mounts in a mount subtree\n"
+	  "containing the directory dir:\n"
+	  "       mount --make-rshared dir\n"
+	  "       mount --make-rslave dir\n"
+	  "       mount --make-rprivate dir\n"
+	  "       mount --make-runbindable dir\n"
 	  "A device can be given by name, say /dev/hda1 or /dev/cdrom,\n"
 	  "or by label, using  -L label  or by uuid, using  -U uuid .\n"
 	  "Other options: [-nfFrsvw] [-o options] [-p passwdfd].\n"
@@ -1638,6 +1666,39 @@
 		case 135:
 			mounttype = (MS_BIND | MS_REC);
 			break;
+
+		case 136:
+			mounttype = MS_SHARED;
+			break;
+
+		case 137:
+			mounttype = MS_SLAVE;
+			break;
+
+		case 138:
+			mounttype = MS_PRIVATE;
+			break;
+
+		case 139:
+			mounttype = MS_UNBINDABLE;
+			break;
+
+		case 140:
+			mounttype = (MS_SHARED | MS_REC);
+			break;
+
+		case 141:
+			mounttype = (MS_SLAVE | MS_REC);
+			break;
+
+		case 142:
+			mounttype = (MS_PRIVATE | MS_REC);
+			break;
+
+		case 143:
+			mounttype = (MS_UNBINDABLE | MS_REC);
+			break;
+
 		case '?':
 		default:
 			usage (stderr, EX_USAGE);