dm thin: include metadata_low_watermark threshold in pool status

[linux-2.6-microblaze.git] / Documentation / device-mapper / thin-provisioning.txt

diff --git a/Documentation/device-mapper/thin-provisioning.txt b/Documentation/device-mapper/thin-provisioning.txt
index b8a57b9..883e7ca 100644 (file)
--- a/Documentation/device-mapper/thin-provisioning.txt
+++ b/Documentation/device-mapper/thin-provisioning.txt
@@ -281,7 +281,7 @@ ii) Status
     <transaction id> <used metadata blocks>/<total metadata blocks>
     <used data blocks>/<total data blocks> <held metadata root>
     ro|rw|out_of_data_space [no_]discard_passdown [error|queue]_if_no_space
-    needs_check|-
+    needs_check|- metadata_low_watermark
 
     transaction id:
        A 64-bit number used by userspace to help synchronise with metadata
@@ -328,6 +328,11 @@ ii) Status
        thin-pool can be made fully operational again.  '-' indicates
        needs_check is not set.
 
+    metadata_low_watermark:
+       Value of metadata low watermark in blocks.  The kernel sets this
+       value internally but userspace needs to know this value to
+       determine if an event was caused by crossing this threshold.
+
 iii) Messages
 
     create_thin <dev id>