diff options
| author | cornelia.huck <cornelia.huck@0c8fb4dd-22a2-4bb5-bc14-6c75a5f43652> | 2013-10-30 15:05:21 +0000 |
|---|---|---|
| committer | cornelia.huck <cornelia.huck@0c8fb4dd-22a2-4bb5-bc14-6c75a5f43652> | 2013-10-30 15:05:21 +0000 |
| commit | 080656277fe8607d5dd1e76ad4a6434c89be5705 (patch) | |
| tree | c22de50684e1de72b228ce14bbf14a721cce17d5 | |
| parent | 80f24376d88b3e25496aa2b3a5ee9e0903bb40e7 (diff) | |
virtio-ccw: clarify some channel I/O concepts
Add the documents where channel I/O is generally described to the
normative references and add some further words on command rejects
and length checks.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
git-svn-id: https://tools.oasis-open.org/version-control/svn/virtio@73 0c8fb4dd-22a2-4bb5-bc14-6c75a5f43652
| -rw-r--r-- | virtio-v1.0-wd01-part1-specification.txt | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/virtio-v1.0-wd01-part1-specification.txt b/virtio-v1.0-wd01-part1-specification.txt index b9e27ea..ae79444 100644 --- a/virtio-v1.0-wd01-part1-specification.txt +++ b/virtio-v1.0-wd01-part1-specification.txt @@ -67,6 +67,10 @@ Driver [RFC 2119] S. Bradner, Key words for use in RFCs to Indicate Requirement Levels, http://www.ietf.org/rfc/rfc2119.txt IETF (Internet Engineering Task Force) RFC 2119, March 1997. +[S390 PoP] z/Architecture Principles of Operation, IBM Publication SA22-7832 + +[S390 Common I/O] ESA/390 Common I/O-Device and Self-Description, IBM Publication SA22-7204 + 1.3. Non-Normative References ========================= @@ -1717,6 +1721,23 @@ virtio: #define CCW_CMD_WRITE_STATUS 0x31 #define CCW_CMD_READ_VQ_CONF 0x32 +The virtio-ccw device acts like a normal channel device, as specified +in [S390 PoP] and [S390 Common I/O]. In particular: + +- A device must post a unit check with command reject for any command + it does not support. + +- If a driver did not suppress length checks for a channel command, + the device must present a subchannel status as detailed in the + architecture when the actual length did not match the expected length. + +- If a driver did suppress length checks for a channel command, the + device must present a check condition if the transmitted data does + not contain enough data to process the command. If the driver submitted + a buffer that was too long, the device should accept the command. + The driver should attempt to provide the correct length even if it + suppresses length checks. + 2.3.3.2. Device Initialization ------------------------------ |