Re: [Qemu-devel] [PATCH 8/8] s390: Add new channel I/O based virtio transport.

[Christian Borntraeger]

On 11/12/12 11:53, Alexander Graf wrote:
> 
> On 07.12.2012, at 13:50, Cornelia Huck wrote:
> 
>> Add a new virtio transport that uses channel commands to perform
>> virtio operations.
>>
>> Add a new machine type s390-ccw that uses this virtio-ccw transport
>> and make it the default machine for s390.
>>
>> Signed-off-by: Cornelia Huck <address@hidden>
>> ---
>> hw/s390-virtio.c       | 149 ++++++--
>> hw/s390x/Makefile.objs |   1 +
>> hw/s390x/virtio-ccw.c  | 909 
>> +++++++++++++++++++++++++++++++++++++++++++++++++
>> hw/s390x/virtio-ccw.h  |  81 +++++
>> trace-events           |   4 +
>> 5 files changed, 1124 insertions(+), 20 deletions(-)
>> create mode 100644 hw/s390x/virtio-ccw.c
>> create mode 100644 hw/s390x/virtio-ccw.h
>>
>> diff --git a/hw/s390-virtio.c b/hw/s390-virtio.c
>> index 9e1afb2..f29ff74 100644
>> --- a/hw/s390-virtio.c
>> +++ b/hw/s390-virtio.c
>> @@ -33,6 +33,8 @@
>>
>> #include "hw/s390-virtio-bus.h"
>> #include "hw/s390x/sclp.h"
>> +#include "hw/s390x/css.h"
>> +#include "hw/s390x/virtio-ccw.h"
>>
>> //#define DEBUG_S390
>>
>> @@ -47,6 +49,7 @@
>> #define KVM_S390_VIRTIO_NOTIFY          0
>> #define KVM_S390_VIRTIO_RESET           1
>> #define KVM_S390_VIRTIO_SET_STATUS      2
>> +#define KVM_S390_VIRTIO_CCW_NOTIFY      3
>>
>> #define KERN_IMAGE_START                0x010000UL
>> #define KERN_PARM_AREA                  0x010480UL
>> @@ -63,6 +66,7 @@
>>
>> static VirtIOS390Bus *s390_bus;
>> static S390CPU **ipi_states;
>> +VirtioCcwBus *ccw_bus;
>>
>> S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
>> {
>> @@ -76,15 +80,21 @@ S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
>> int s390_virtio_hypercall(CPUS390XState *env, uint64_t mem, uint64_t 
>> hypercall)
>> {
>>     int r = 0, i;
>> +    int cssid, ssid, schid, m;
>> +    SubchDev *sch;
>>
>>     dprintf("KVM hypercall: %ld\n", hypercall);
>>     switch (hypercall) {
>>     case KVM_S390_VIRTIO_NOTIFY:
>>         if (mem > ram_size) {
>> -            VirtIOS390Device *dev = s390_virtio_bus_find_vring(s390_bus,
>> -                                                               mem, &i);
>> -            if (dev) {
>> -                virtio_queue_notify(dev->vdev, i);
>> +            if (s390_bus) {
>> +                VirtIOS390Device *dev = s390_virtio_bus_find_vring(s390_bus,
>> +                                                                   mem, &i);
>> +                if (dev) {
>> +                    virtio_queue_notify(dev->vdev, i);
>> +                } else {
>> +                    r = -EINVAL;
>> +                }
> 
> We really want to factor out the DIAG handling code similar to how spapr 
> handles its hypercalls. That way the legacy s390-virtio machine can register 
> a VIRTIO_NOTIFY hypercall that works for it here, while the s390-virtio-ccw 
> machine doesn't.
> 

Agreed, but this has nothing to do with virtio-ccw and should be part of a 
follow-up cleanup. no?

Christian