virtio — archive

[Cornelia Huck]

Unlike other transports, a reset triggered by the driver is actually complete once the command has been completed. Make this behaviour and the requirements more explicit. Signed-off-by: Cornelia Huck <cohuck@redhat.com> --- We have discussed this before while talking about reset behaviour, but I don't remember sending an actual patch. If this looks good, I'll open an issue. --- conformance.tex 2 ++ content.tex 22 +++++++++++++++++++++- 2 files changed, 23 insertions(+), 1 deletion(-) diff --git a/conformance.tex b/conformance.tex index c52f1a40be2d..24e862ad217a 100644 --- a/conformance.tex +++ b/conformance.tex @@ -122,6 +122,7 @@ section{Conformance Targets}label{sec:Conformance / Conformance Targets} item ef{drivernormative:Virtio Transport Options / Virtio over channel I/O / Device Initialization / Communicating Status Information} item ef{drivernormative:Virtio Transport Options / Virtio over channel I/O / Device Operation / Host->Guest Notification / Notification via Adapter I/O Interrupts} item ef{drivernormative:Virtio Transport Options / Virtio over channel I/O / Device Operation / Guest->Host Notification} +item ef{drivernormative:Virtio Transport Options / Virtio over channel I/O / Device Operation / Resetting Devices} end{itemize} conformance{subsection}{Network Driver Conformance}label{sec:Conformance / Driver Conformance / Network Driver Conformance} @@ -372,6 +373,7 @@ section{Conformance Targets}label{sec:Conformance / Conformance Targets} item ef{devicenormative:Virtio Transport Options / Virtio over channel I/O / Device Initialization / Setting Up Indicators / Setting Up Two-Stage Queue Indicators} item ef{devicenormative:Virtio Transport Options / Virtio over channel I/O / Device Operation / Host->Guest Notification / Notification via Adapter I/O Interrupts} item ef{devicenormative:Virtio Transport Options / Virtio over channel I/O / Device Operation / Guest->Host Notification} +item ef{devicenormative:Virtio Transport Options / Virtio over channel I/O / Device Operation / Resetting Devices} end{itemize} conformance{subsection}{Network Device Conformance}label{sec:Conformance / Device Conformance / Network Device Conformance} diff --git a/content.tex b/content.tex index 5e716721edb3..0410f46f6a78 100644 --- a/content.tex +++ b/content.tex @@ -2775,8 +2775,28 @@ subsubsection{Guest->Host Notification}label{sec:Virtio Transport Options / Vi subsubsection{Resetting Devices}label{sec:Virtio Transport Options / Virtio over channel I/O / Device Operation / Resetting Devices} In order to reset a device, a driver sends the -CCW_CMD_VDEV_RESET command. +CCW_CMD_VDEV_RESET command. This command does not carry any payload. +The device signals completion of the reset operation by making the subchannel +status pending to indicate successful completion of the channel command. +Notably, the command not only triggers the reset operation, but the reset +operation is already completed when the operation concludes successfully. + +devicenormative{paragraph}{Resetting Devices}{Virtio Transport Options / Virtio over channel I/O / Device Operation / Resetting Devices} + +Before making the subchannel status pending to indicate successful completion +of the reset command, the device MUST reinitialize field{device status} to +zero. + +The device MUST NOT send notifications or interact with the queues after +it signaled successful completion of the reset command. + +drivernormative{paragraph}{Resetting Devices}{Virtio Transport Options / Virtio over channel I/O / Device Operation / Resetting Devices} + +The driver MAY consider the reset operation to be complete already after +successful completion of the channel command, although it MAY also verify +reset completion by reading field{device status} via CCW_CMD_READ_STATUS +afterwards. chapter{Device Types}label{sec:Device Types} -- 2.31.1