mount: "nofail" mount option

It would be nice to have a mount option "nofail" indicating that mount
should not return an error if the device does not exit. This is useful
for hotpluggable devices which are configured in fstab and __might__
not exist at boot time.

Co-Author: Karel Zak <kzak@redhat.com>
Signed-off-by: Matthias Koenig <mkoenig@suse.de>
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/mount/mount.8 b/mount/mount.8
index 54b11d46962d7ad44c8d77104078707af95d9bbd..ce52dd84dde73e4a68bfc19df5e13c84010c5fd4 100644 (file)
--- a/mount/mount.8
+++ b/mount/mount.8
@@ -615,6 +615,9 @@ This option implies the options
 (unless overridden by subsequent options, as in the option line
 .BR group,dev,suid ).
 .TP
+.B nofail
+Do not report errors for this device if it does not exist.
+.TP
 .B mand
 Allow mandatory locks on this filesystem. See
 .BR fcntl (2).

diff --git a/mount/mount.c b/mount/mount.c
index 917f62ac4f269e69baa614cf4824246add98b29e..0688c57ff58f78dcad86b3707021b1175f684ee6 100644 (file)
--- a/mount/mount.c
+++ b/mount/mount.c
@@ -176,9 +176,12 @@ static const struct opt_map opt_map[] = {
   { "norelatime", 0, 1, MS_RELATIME }, /* Update access time without regard
                                          to mtime/ctime */
 #endif
+  { "nofail",  0, 0, MS_COMMENT},      /* Do not fail if ENOENT on dev */
   { NULL,      0, 0, 0         }
 };
 
+static int opt_nofail = 0;
+
 static const char *opt_loopdev, *opt_vfstype, *opt_offset, *opt_encryption,
        *opt_speed, *opt_comment, *opt_uhelper;
 
@@ -383,6 +386,8 @@ parse_opt(char *opt, int *mask, char **extra_opts) {
                                verbose = 0;
                        }
 #endif
+                       if (streq(opt, "nofail"))
+                               opt_nofail = 1;
                        return;
                }
 
@@ -1198,9 +1203,11 @@ try_mount_one (const char *spec0, const char *node0, const char *types0,
       else if (stat (node, &statbuf))
           error (_("mount: mount point %s is a symbolic link to nowhere"),
                  node);
-      else if (stat (spec, &statbuf))
+      else if (stat (spec, &statbuf)) {
+          if (opt_nofail)
+               goto out;
           error (_("mount: special device %s does not exist"), spec);
-      else {
+      } else {
           errno = mnt_err;
           perror("mount");
       }
@@ -1208,10 +1215,12 @@ try_mount_one (const char *spec0, const char *node0, const char *types0,
     case ENOTDIR:
       if (stat (node, &statbuf) || ! S_ISDIR(statbuf.st_mode))
           error (_("mount: mount point %s is not a directory"), node);
-      else if (stat (spec, &statbuf) && errno == ENOTDIR)
+      else if (stat (spec, &statbuf) && errno == ENOTDIR) {
+          if (opt_nofail)
+              goto out;
           error (_("mount: special device %s does not exist\n"
                    "       (a path prefix is not a directory)\n"), spec);
-      else {
+      } else {
           errno = mnt_err;
           perror("mount");
       }
@@ -1296,6 +1305,8 @@ try_mount_one (const char *spec0, const char *node0, const char *types0,
       break;
     }
     case ENOTBLK:
+      if (opt_nofail)
+        goto out;
       if (stat (spec, &statbuf)) /* strange ... */
        error (_("mount: %s is not a block device, and stat fails?"), spec);
       else if (S_ISBLK(statbuf.st_mode))
@@ -1308,6 +1319,8 @@ try_mount_one (const char *spec0, const char *node0, const char *types0,
        error (_("mount: %s is not a block device"), spec);
       break;
     case ENXIO:
+      if (opt_nofail)
+        goto out;
       error (_("mount: %s is not a valid block device"), spec); break;
     case EACCES:  /* pre-linux 1.1.38, 1.1.41 and later */
     case EROFS:   /* linux 1.1.38 and later */