10-dm.rules: bump DM_UDEV_RULES_VSN to 3

Bump the rules version in order to indicate that upper level rules
should consume DM_UDEV_DISABLE_OTHER_RULES_FLAG rather than DM_NOSCAN
and DM_SUSPENDED.

Also update the comments at the top of the file that describe the
exported properties, and add a note about internal device-mapper
properties.

Signed-off-by: Martin Wilck <mwilck@suse.com>
Reviewed-by: Peter Rajnoha <prajnoha@redhat.com>

diff --git a/udev/10-dm.rules.in b/udev/10-dm.rules.in
index 0e2a60e2a6f155d0c9303348d0f9c9a708752275..f8f823e5ea71c0418c91f85770ca0be5c7e1e5e4 100644 (file)
--- a/udev/10-dm.rules.in
+++ b/udev/10-dm.rules.in
@@ -12,6 +12,9 @@
 #   DM_NAME - actual DM device's name
 #   DM_UUID - UUID set for DM device (blank if not specified)
 #   DM_UDEV_RULES_VSN - DM udev rules version
+#   DM_UDEV_DISABLE_OTHER_RULES_FLAG - a flag that indicates that
+#      stacked layers shouldn't attempt to probe the device, and
+#      should try to import relevant properties from the udev db.
 #
 # These rules cover only basic device-mapper functionality in udev.
 #
@@ -22,6 +25,11 @@
 #   11-dm-lvm.rules for LVM subsystem
 #   11-dm-mpath.rules for multipath subsystem (since version 0.6.0, recommended!)
 #
+# 11-dm<subsystem_name>.rules may use other DM related properties besides
+# those listed above, like .DM_SUSPENDED. These properties are considered
+# internal to device mapper, and subject to change without notice.
+# Rules that are executed after 13-dm-disk.rules shouldn't use them.
+#
 # Even more specific rules may be required by subsystems so always
 # check subsystem's upstream repository for recent set of rules.
 # Also, keep in mind that recent rules may also require recent
@@ -139,7 +147,9 @@ LABEL="dm_suspended_set"
 # possible future changes.
 # VSN 1 - original rules
 # VSN 2 - add support for synthesized events
-ENV{DM_UDEV_RULES_VSN}="2"
+# VSN 3 - use DM_UDEV_DISABLE_OTHER_RULES_FLAG as the only "API"
+#         to be consumed by non-dm rules.
+ENV{DM_UDEV_RULES_VSN}="3"
 
 ENV{DM_UDEV_DISABLE_DM_RULES_FLAG}!="1", ENV{DM_NAME}=="?*", SYMLINK+="(DM_DIR)/$env{DM_NAME}"