Re: [PATCH 1/3] kvm: s390: Per-vm kvm device controls

[Alexander Graf <agraf@suse.de>]

On 10.04.14 13:33, Christian Borntraeger wrote:
> On 10/04/14 13:29, Alexander Graf wrote:
>> On 10.04.14 13:16, Christian Borntraeger wrote:
>>> From: Dominik Dingel <dingel@linux.vnet.ibm.com>
>>>
>>> We sometimes need to get/set attributes specific to a virtual machine
>>> and so need something else than ONE_REG.
>>>
>>> Let's copy the KVM_DEVICE approach, and define the respective ioctls
>>> for the vm file descriptor.
>>>
>>> Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
>>> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
>>> ---
>>>    Documentation/virtual/kvm/api.txt        |  8 ++---
>>>    Documentation/virtual/kvm/devices/vm.txt |  6 ++++
>>>    arch/s390/kvm/kvm-s390.c                 | 54 ++++++++++++++++++++++++++++++++
>>>    include/uapi/linux/kvm.h                 |  1 +
>>>    4 files changed, 65 insertions(+), 4 deletions(-)
>>>    create mode 100644 Documentation/virtual/kvm/devices/vm.txt
>>>
>>> diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
>>> index c24211d..f69731a 100644
>>> --- a/Documentation/virtual/kvm/api.txt
>>> +++ b/Documentation/virtual/kvm/api.txt
>>> @@ -2314,8 +2314,8 @@ struct kvm_create_device {
>>>      4.80 KVM_SET_DEVICE_ATTR/KVM_GET_DEVICE_ATTR
>>>    -Capability: KVM_CAP_DEVICE_CTRL
>>> -Type: device ioctl
>>> +Capability: KVM_CAP_DEVICE_CTRL, KVM_CAP_VM_ATTRIBUTES for vm device
>>> +Type: device ioctl, vm ioctl
>>>    Parameters: struct kvm_device_attr
>>>    Returns: 0 on success, -1 on error
>>>    Errors:
>>> @@ -2340,8 +2340,8 @@ struct kvm_device_attr {
>>>      4.81 KVM_HAS_DEVICE_ATTR
>>>    -Capability: KVM_CAP_DEVICE_CTRL
>>> -Type: device ioctl
>>> +Capability: KVM_CAP_DEVICE_CTRL, KVM_CAP_VM_ATTRIBUTES for vm device
>>> +Type: device ioctl, vm ioctl
>>>    Parameters: struct kvm_device_attr
>>>    Returns: 0 on success, -1 on error
>>>    Errors:
>>> diff --git a/Documentation/virtual/kvm/devices/vm.txt b/Documentation/virtual/kvm/devices/vm.txt
>>> new file mode 100644
>>> index 0000000..4fe1532
>>> --- /dev/null
>>> +++ b/Documentation/virtual/kvm/devices/vm.txt
>>> @@ -0,0 +1,6 @@
>>> +Generic vm interface
>>> +====================================
>>> +
>>> +The interface handles per-vm attributes, such as CMMA status on s390 and is
>>> +similar in way to ONE_REG, but targeting the whole vm instead of one vcpu
>>> +alone. It is available with KVM_CAP_VM_ATTRIBUTES.
>> This document doesn't sound impressively useful :).
> Will be filled with patch3. I asked Dominik to split this out into this patch,
> since we introduce the capability here.

Ah, it's in .../devices/. Fair enough.


Alex