From: Cornelia Huck <[email protected]>
Update documentation for dynamic subchannel mapping.
Signed-off-by: Cornelia Huck <[email protected]>
---
Documentation/s390/driver-model.txt | 7 +++++++
1 files changed, 7 insertions(+)
--- linux-2.6-CH.orig/Documentation/s390/driver-model.txt
+++ linux-2.6-CH/Documentation/s390/driver-model.txt
@@ -18,11 +18,18 @@ devices/
- 0.0.0002/
- 0.1.0000/0.1.1234/
...
+ - defunct/
In this example, device 0815 is accessed via subchannel 0 in subchannel set 0,
device 4711 via subchannel 1 in subchannel set 0, and subchannel 2 is a non-I/O
subchannel. Device 1234 is accessed via subchannel 0 in subchannel set 1.
+The subchannel named 'defunct' does not represent any real subchannel on the
+system; it is a pseudo subchannel where disconnnected ccw devices are moved to
+if they are displaced by another ccw device becoming operational on their
+former subchannel. The ccw devices will be moved again to a proper subchannel
+if they become operational again on that subchannel.
+
You should address a ccw device via its bus id (e.g. 0.0.4711); the device can
be found under bus/ccw/devices/.