Change /etc/mtab to /proc/self/mounts

Fix misleading error message:

 "The /dev/zfs device is missing and must be created.", if /etc/mtab is missing.

Reviewed-by: Richard Laager <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Eric Desrochers <[email protected]>
Closes #4680 
Closes #5029

1 files changed, 6 insertions, 5 deletions

diff --git a/lib/libzfs/libzfs_dataset.c b/lib/libzfs/libzfs_dataset.c
index 3ac31ad1d..84fe71734 100755
--- a/lib/libzfs/libzfs_dataset.c
+++ b/lib/libzfs/libzfs_dataset.c
@@ -1908,9 +1908,9 @@ zfs_unset_recvd_props_mode(zfs_handle_t *zhp, uint64_t *cookie)
  * zfs_prop_get_int() are built using this interface.
  *
  * Certain properties can be overridden using 'mount -o'.  In this case, scan
- * the contents of the /etc/mtab entry, searching for the appropriate options.
- * If they differ from the on-disk values, report the current values and mark
- * the source "temporary".
+ * the contents of the /proc/self/mounts entry, searching for the
+ * appropriate options. If they differ from the on-disk values, report the
+ * current values and mark the source "temporary".
  */
 static int
 get_numeric_property(zfs_handle_t *zhp, zfs_prop_t prop, zprop_source_t *src,
@@ -1981,8 +1981,9 @@ get_numeric_property(zfs_handle_t *zhp, zfs_prop_t prop, zprop_source_t *src,
 
 	/*
 	 * Because looking up the mount options is potentially expensive
-	 * (iterating over all of /etc/mtab), we defer its calculation until
-	 * we're looking up a property which requires its presence.
+	 * (iterating over all of /proc/self/mounts), we defer its
+	 * calculation until we're looking up a property which requires
+	 * its presence.
 	 */
 	if (!zhp->zfs_mntcheck &&
 	    (mntopt_on != NULL || prop == ZFS_PROP_MOUNTED)) {