Re: [Qemu-devel] [PATCH v2 3/4] virtio-ccw: use ccw data stream

[Dong Jia Shi]

* Halil Pasic  [2017-09-19 15:30:29 +0200]:

> 
> 
> On 09/19/2017 11:06 AM, Cornelia Huck wrote:
> > On Tue, 19 Sep 2017 11:37:30 +0800
> > Dong Jia Shi  wrote:
> > 
> >> * Halil Pasic  [2017-09-13 13:50:28 +0200]:
> >>
> >>> Replace direct access which implicitly assumes no IDA
> >>> or MIDA with the new ccw data stream interface which should
> >>> cope with these transparently in the future.
> >>>
> >>> Signed-off-by: Halil Pasic 
> >>>
> >>> ---
> >>>
> >>> v1 --> v2:
> >>> Removed todo comments on possible errno change as with
> >>> https://lists.nongnu.org/archive/html/qemu-devel/2017-09/msg02441.html
> >>> applied it does not matter any more.
> >>>
> >>> Error handling: At the moment we ignore errors reported
> >>> by stream ops to keep the change minimal. An add-on
> >>> patch improving on this is to be expected later.  
> >> Add a TODO somewhere around the code as a reminder?
> > 
> > I expect Halil to have it on his TODO list and send a patch later ;)
No problem with me.

> > 
> >>
> >>> ---
> >>>  hw/s390x/virtio-ccw.c | 156 
> >>> +++---
> >>>  1 file changed, 46 insertions(+), 110 deletions(-)
> >>>
> >>> diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
> >>> index b1976fdd19..a9baf6f7ab 100644
> >>> --- a/hw/s390x/virtio-ccw.c
> >>> +++ b/hw/s390x/virtio-ccw.c  
> >> [...]
> >>
> >>> @@ -394,11 +362,8 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
> >>>  } else {
> >>>  VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
> >>>
> >>> -features.index = address_space_ldub(_space_memory,
> >>> -ccw.cda
> >>> -+ 
> >>> sizeof(features.features),
> >>> -MEMTXATTRS_UNSPECIFIED,
> >>> -NULL);
> >>> +ccw_dstream_advance(>cds, sizeof(features.features));  
> >> How about:
> >> ccw_dstream_advance(>cds, offsetof(VirtioFeatDesc, index));
> > 
> > I think keeping sizeof(features.features) is better: It matches the old
> > code, and we really do jump over the features flag and revisit it
> > later...
I was thinking 'advance' to the offset of features.index, then 'read'
the value for features.index seems more natural, and you do not need to
care too much for what exaclty the elements are that you need to
'advance'.

Not big deal for me. I could also accept the original version.

> > 
> >>
> >>> +ccw_dstream_read(>cds, features.index);
> >>>  if (features.index == 0) {
> >>>  if (dev->revision >= 1) {
> >>>  /* Don't offer legacy features for modern devices. */
> >>> @@ -417,9 +382,9 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
> >>>  /* Return zeroes if the guest supports more feature 
> >>> bits. */
> >>>  features.features = 0;
> >>>  }
> >>> -address_space_stl_le(_space_memory, ccw.cda,
> >>> - features.features, 
> >>> MEMTXATTRS_UNSPECIFIED,
> >>> - NULL);
> >>> +ccw_dstream_rewind(>cds);
> >>> +cpu_to_le32s();
> >>> +ccw_dstream_write(>cds, features.features);
> >>>  sch->curr_status.scsw.count = ccw.count - sizeof(features);  
> >> How about:
> >> sch->curr_status.scsw.count = ccw_dstream_residual_count(>cds);
> > 
> > Hm, I thought I had commented on this, but I seem to have missed
> > these...
> > 
> > I'd prefer to do it as a follow-up patch.
No problem.

> > 
> >>
> >> This also applies to other places.
> >>
> >>>  ret = 0;
> >>>  }  
> >> [...]
> >>
> >>> @@ -501,21 +459,13 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
> >>>  }
> >>>  }
> >>>  len = MIN(ccw.count, vdev->config_len);
> >>> -hw_len = len;
> >>>  if (!ccw.cda) {
> >>>  ret = -EFAULT;
> >>>  } else {
> >>> -config = cpu_physical_memory_map(ccw.cda, _len, 0);
> >>> -if (!config) {
> >>> -ret = -EFAULT;
> >>> -} else {
> >>> -len = hw_len;
> >>> -/* XXX config space endianness */
> >>> -memcpy(vdev->config, config, len);
> >>> -cpu_physical_memory_unmap(config, hw_len, 0, hw_len);
> >>> +ret = ccw_dstream_read_buf(>cds, vdev->config, len);
> >>> +if (!ret) {  
> >> Add a TODO here, and:
> >>
> >> if (ccw_dstream_read_buf(>cds, vdev->config, len)) {
> >> ret = -EFAULT;
> >> } else {
> >> 
> >> }
> > 
> > I don't think that would be correct: The function will (at least
> > currently) return 0 or -EINVAL, and you are now mapping any error to
> > -EFAULT? (Not that it 

Re: [Qemu-devel] [PATCH v2 3/4] virtio-ccw: use ccw data stream

[Pierre Morel]

On 13/09/2017 13:50, Halil Pasic wrote:

Replace direct access which implicitly assumes no IDA
or MIDA with the new ccw data stream interface which should
cope with these transparently in the future.

Signed-off-by: Halil Pasic 

---

v1 --> v2:
Removed todo comments on possible errno change as with
https://lists.nongnu.org/archive/html/qemu-devel/2017-09/msg02441.html
applied it does not matter any more.

Error handling: At the moment we ignore errors reported
by stream ops to keep the change minimal. An add-on
patch improving on this is to be expected later.
---
  hw/s390x/virtio-ccw.c | 156 +++---
  1 file changed, 46 insertions(+), 110 deletions(-)


:)



diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
index b1976fdd19..a9baf6f7ab 100644
--- a/hw/s390x/virtio-ccw.c
+++ b/hw/s390x/virtio-ccw.c
@@ -287,49 +287,19 @@ static int virtio_ccw_handle_set_vq(SubchDev *sch, CCW1 
ccw, bool check_len,
  return -EFAULT;
  }
  if (is_legacy) {
-linfo.queue = address_space_ldq_be(_space_memory, ccw.cda,
-   MEMTXATTRS_UNSPECIFIED, NULL);
-linfo.align = address_space_ldl_be(_space_memory,
-   ccw.cda + sizeof(linfo.queue),
-   MEMTXATTRS_UNSPECIFIED,
-   NULL);
-linfo.index = address_space_lduw_be(_space_memory,
-ccw.cda + sizeof(linfo.queue)
-+ sizeof(linfo.align),
-MEMTXATTRS_UNSPECIFIED,
-NULL);
-linfo.num = address_space_lduw_be(_space_memory,
-  ccw.cda + sizeof(linfo.queue)
-  + sizeof(linfo.align)
-  + sizeof(linfo.index),
-  MEMTXATTRS_UNSPECIFIED,
-  NULL);
+ccw_dstream_read(>cds, linfo);
+be64_to_cpus();
+be32_to_cpus();
+be16_to_cpus();
+be16_to_cpus();
  ret = virtio_ccw_set_vqs(sch, NULL, );
  } else {
-info.desc = address_space_ldq_be(_space_memory, ccw.cda,
-   MEMTXATTRS_UNSPECIFIED, NULL);
-info.index = address_space_lduw_be(_space_memory,
-   ccw.cda + sizeof(info.desc)
-   + sizeof(info.res0),
-   MEMTXATTRS_UNSPECIFIED, NULL);
-info.num = address_space_lduw_be(_space_memory,
- ccw.cda + sizeof(info.desc)
- + sizeof(info.res0)
- + sizeof(info.index),
- MEMTXATTRS_UNSPECIFIED, NULL);
-info.avail = address_space_ldq_be(_space_memory,
-  ccw.cda + sizeof(info.desc)
-  + sizeof(info.res0)
-  + sizeof(info.index)
-  + sizeof(info.num),
-  MEMTXATTRS_UNSPECIFIED, NULL);
-info.used = address_space_ldq_be(_space_memory,
- ccw.cda + sizeof(info.desc)
- + sizeof(info.res0)
- + sizeof(info.index)
- + sizeof(info.num)
- + sizeof(info.avail),
- MEMTXATTRS_UNSPECIFIED, NULL);
+ccw_dstream_read(>cds, info);
+be64_to_cpus();
+be16_to_cpus();
+be16_to_cpus();
+be64_to_cpus();
+be64_to_cpus();
  ret = virtio_ccw_set_vqs(sch, , NULL);
  }
  sch->curr_status.scsw.count = 0;
@@ -342,15 +312,13 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
  VirtioRevInfo revinfo;
  uint8_t status;
  VirtioFeatDesc features;
-void *config;
  hwaddr indicators;
  VqConfigBlock vq_config;
  VirtioCcwDevice *dev = sch->driver_data;
  VirtIODevice *vdev = virtio_ccw_get_vdev(sch);
  bool check_len;
  int len;
-hwaddr hw_len;
-VirtioThinintInfo *thinint;
+VirtioThinintInfo thinint;

  if (!dev) {
  return -EINVAL;
@@ -394,11 +362,8 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
  } else {
  VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);

-features.index = address_space_ldub(_space_memory,
-ccw.cda
-

Re: [Qemu-devel] [PATCH v2 3/4] virtio-ccw: use ccw data stream

[Halil Pasic]

On 09/19/2017 11:06 AM, Cornelia Huck wrote:
> On Tue, 19 Sep 2017 11:37:30 +0800
> Dong Jia Shi  wrote:
> 
>> * Halil Pasic  [2017-09-13 13:50:28 +0200]:
>>
>>> Replace direct access which implicitly assumes no IDA
>>> or MIDA with the new ccw data stream interface which should
>>> cope with these transparently in the future.
>>>
>>> Signed-off-by: Halil Pasic 
>>>
>>> ---
>>>
>>> v1 --> v2:
>>> Removed todo comments on possible errno change as with
>>> https://lists.nongnu.org/archive/html/qemu-devel/2017-09/msg02441.html
>>> applied it does not matter any more.
>>>
>>> Error handling: At the moment we ignore errors reported
>>> by stream ops to keep the change minimal. An add-on
>>> patch improving on this is to be expected later.  
>> Add a TODO somewhere around the code as a reminder?
> 
> I expect Halil to have it on his TODO list and send a patch later ;)
> 
>>
>>> ---
>>>  hw/s390x/virtio-ccw.c | 156 
>>> +++---
>>>  1 file changed, 46 insertions(+), 110 deletions(-)
>>>
>>> diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
>>> index b1976fdd19..a9baf6f7ab 100644
>>> --- a/hw/s390x/virtio-ccw.c
>>> +++ b/hw/s390x/virtio-ccw.c  
>> [...]
>>
>>> @@ -394,11 +362,8 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
>>>  } else {
>>>  VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
>>>
>>> -features.index = address_space_ldub(_space_memory,
>>> -ccw.cda
>>> -+ 
>>> sizeof(features.features),
>>> -MEMTXATTRS_UNSPECIFIED,
>>> -NULL);
>>> +ccw_dstream_advance(>cds, sizeof(features.features));  
>> How about:
>> ccw_dstream_advance(>cds, offsetof(VirtioFeatDesc, index));
> 
> I think keeping sizeof(features.features) is better: It matches the old
> code, and we really do jump over the features flag and revisit it
> later...
> 
>>
>>> +ccw_dstream_read(>cds, features.index);
>>>  if (features.index == 0) {
>>>  if (dev->revision >= 1) {
>>>  /* Don't offer legacy features for modern devices. */
>>> @@ -417,9 +382,9 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
>>>  /* Return zeroes if the guest supports more feature bits. 
>>> */
>>>  features.features = 0;
>>>  }
>>> -address_space_stl_le(_space_memory, ccw.cda,
>>> - features.features, MEMTXATTRS_UNSPECIFIED,
>>> - NULL);
>>> +ccw_dstream_rewind(>cds);
>>> +cpu_to_le32s();
>>> +ccw_dstream_write(>cds, features.features);
>>>  sch->curr_status.scsw.count = ccw.count - sizeof(features);  
>> How about:
>> sch->curr_status.scsw.count = ccw_dstream_residual_count(>cds);
> 
> Hm, I thought I had commented on this, but I seem to have missed
> these...
> 
> I'd prefer to do it as a follow-up patch.
> 
>>
>> This also applies to other places.
>>
>>>  ret = 0;
>>>  }  
>> [...]
>>
>>> @@ -501,21 +459,13 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
>>>  }
>>>  }
>>>  len = MIN(ccw.count, vdev->config_len);
>>> -hw_len = len;
>>>  if (!ccw.cda) {
>>>  ret = -EFAULT;
>>>  } else {
>>> -config = cpu_physical_memory_map(ccw.cda, _len, 0);
>>> -if (!config) {
>>> -ret = -EFAULT;
>>> -} else {
>>> -len = hw_len;
>>> -/* XXX config space endianness */
>>> -memcpy(vdev->config, config, len);
>>> -cpu_physical_memory_unmap(config, hw_len, 0, hw_len);
>>> +ret = ccw_dstream_read_buf(>cds, vdev->config, len);
>>> +if (!ret) {  
>> Add a TODO here, and:
>>
>> if (ccw_dstream_read_buf(>cds, vdev->config, len)) {
>> ret = -EFAULT;
>> } else {
>> 
>> }
> 
> I don't think that would be correct: The function will (at least
> currently) return 0 or -EINVAL, and you are now mapping any error to
> -EFAULT? (Not that it has an effect in the end: We map both to a
> channel program check as of "s390x/css: drop data-check in
> interpretation".)
> 
>>
>>>  virtio_bus_set_vdev_config(>bus, vdev->config);
>>>  sch->curr_status.scsw.count = ccw.count - len;
>>> -ret = 0;
>>>  }
>>>  }
>>>  break;  
>> [...]
>>
>>> @@ -714,13 +654,9 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
>>>  ret = -EFAULT;
>>>  break;
>>>  }
>>> -revinfo.revision =
>>> -address_space_lduw_be(_space_memory, ccw.cda,
>>> -   

Re: [Qemu-devel] [PATCH v2 3/4] virtio-ccw: use ccw data stream

[Cornelia Huck]

On Tue, 19 Sep 2017 11:37:30 +0800
Dong Jia Shi  wrote:

> * Halil Pasic  [2017-09-13 13:50:28 +0200]:
> 
> > Replace direct access which implicitly assumes no IDA
> > or MIDA with the new ccw data stream interface which should
> > cope with these transparently in the future.
> > 
> > Signed-off-by: Halil Pasic 
> > 
> > ---
> > 
> > v1 --> v2:
> > Removed todo comments on possible errno change as with
> > https://lists.nongnu.org/archive/html/qemu-devel/2017-09/msg02441.html
> > applied it does not matter any more.
> > 
> > Error handling: At the moment we ignore errors reported
> > by stream ops to keep the change minimal. An add-on
> > patch improving on this is to be expected later.  
> Add a TODO somewhere around the code as a reminder?

I expect Halil to have it on his TODO list and send a patch later ;)

> 
> > ---
> >  hw/s390x/virtio-ccw.c | 156 
> > +++---
> >  1 file changed, 46 insertions(+), 110 deletions(-)
> > 
> > diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
> > index b1976fdd19..a9baf6f7ab 100644
> > --- a/hw/s390x/virtio-ccw.c
> > +++ b/hw/s390x/virtio-ccw.c  
> [...]
> 
> > @@ -394,11 +362,8 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
> >  } else {
> >  VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
> > 
> > -features.index = address_space_ldub(_space_memory,
> > -ccw.cda
> > -+ 
> > sizeof(features.features),
> > -MEMTXATTRS_UNSPECIFIED,
> > -NULL);
> > +ccw_dstream_advance(>cds, sizeof(features.features));  
> How about:
> ccw_dstream_advance(>cds, offsetof(VirtioFeatDesc, index));

I think keeping sizeof(features.features) is better: It matches the old
code, and we really do jump over the features flag and revisit it
later...

> 
> > +ccw_dstream_read(>cds, features.index);
> >  if (features.index == 0) {
> >  if (dev->revision >= 1) {
> >  /* Don't offer legacy features for modern devices. */
> > @@ -417,9 +382,9 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
> >  /* Return zeroes if the guest supports more feature bits. 
> > */
> >  features.features = 0;
> >  }
> > -address_space_stl_le(_space_memory, ccw.cda,
> > - features.features, MEMTXATTRS_UNSPECIFIED,
> > - NULL);
> > +ccw_dstream_rewind(>cds);
> > +cpu_to_le32s();
> > +ccw_dstream_write(>cds, features.features);
> >  sch->curr_status.scsw.count = ccw.count - sizeof(features);  
> How about:
> sch->curr_status.scsw.count = ccw_dstream_residual_count(>cds);

Hm, I thought I had commented on this, but I seem to have missed
these...

I'd prefer to do it as a follow-up patch.

> 
> This also applies to other places.
> 
> >  ret = 0;
> >  }  
> [...]
> 
> > @@ -501,21 +459,13 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
> >  }
> >  }
> >  len = MIN(ccw.count, vdev->config_len);
> > -hw_len = len;
> >  if (!ccw.cda) {
> >  ret = -EFAULT;
> >  } else {
> > -config = cpu_physical_memory_map(ccw.cda, _len, 0);
> > -if (!config) {
> > -ret = -EFAULT;
> > -} else {
> > -len = hw_len;
> > -/* XXX config space endianness */
> > -memcpy(vdev->config, config, len);
> > -cpu_physical_memory_unmap(config, hw_len, 0, hw_len);
> > +ret = ccw_dstream_read_buf(>cds, vdev->config, len);
> > +if (!ret) {  
> Add a TODO here, and:
> 
> if (ccw_dstream_read_buf(>cds, vdev->config, len)) {
> ret = -EFAULT;
> } else {
> 
> }

I don't think that would be correct: The function will (at least
currently) return 0 or -EINVAL, and you are now mapping any error to
-EFAULT? (Not that it has an effect in the end: We map both to a
channel program check as of "s390x/css: drop data-check in
interpretation".)

> 
> >  virtio_bus_set_vdev_config(>bus, vdev->config);
> >  sch->curr_status.scsw.count = ccw.count - len;
> > -ret = 0;
> >  }
> >  }
> >  break;  
> [...]
> 
> > @@ -714,13 +654,9 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
> >  ret = -EFAULT;
> >  break;
> >  }
> > -revinfo.revision =
> > -address_space_lduw_be(_space_memory, ccw.cda,
> > -  MEMTXATTRS_UNSPECIFIED, NULL);
> > -revinfo.length =
> > -

Re: [Qemu-devel] [PATCH v2 3/4] virtio-ccw: use ccw data stream

[Dong Jia Shi]

* Halil Pasic  [2017-09-13 13:50:28 +0200]:

> Replace direct access which implicitly assumes no IDA
> or MIDA with the new ccw data stream interface which should
> cope with these transparently in the future.
> 
> Signed-off-by: Halil Pasic 
> 
> ---
> 
> v1 --> v2:
> Removed todo comments on possible errno change as with
> https://lists.nongnu.org/archive/html/qemu-devel/2017-09/msg02441.html
> applied it does not matter any more.
> 
> Error handling: At the moment we ignore errors reported
> by stream ops to keep the change minimal. An add-on
> patch improving on this is to be expected later.
Add a TODO somewhere around the code as a reminder?

> ---
>  hw/s390x/virtio-ccw.c | 156 
> +++---
>  1 file changed, 46 insertions(+), 110 deletions(-)
> 
> diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
> index b1976fdd19..a9baf6f7ab 100644
> --- a/hw/s390x/virtio-ccw.c
> +++ b/hw/s390x/virtio-ccw.c
[...]

> @@ -394,11 +362,8 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
>  } else {
>  VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
> 
> -features.index = address_space_ldub(_space_memory,
> -ccw.cda
> -+ sizeof(features.features),
> -MEMTXATTRS_UNSPECIFIED,
> -NULL);
> +ccw_dstream_advance(>cds, sizeof(features.features));
How about:
ccw_dstream_advance(>cds, offsetof(VirtioFeatDesc, index));

> +ccw_dstream_read(>cds, features.index);
>  if (features.index == 0) {
>  if (dev->revision >= 1) {
>  /* Don't offer legacy features for modern devices. */
> @@ -417,9 +382,9 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
>  /* Return zeroes if the guest supports more feature bits. */
>  features.features = 0;
>  }
> -address_space_stl_le(_space_memory, ccw.cda,
> - features.features, MEMTXATTRS_UNSPECIFIED,
> - NULL);
> +ccw_dstream_rewind(>cds);
> +cpu_to_le32s();
> +ccw_dstream_write(>cds, features.features);
>  sch->curr_status.scsw.count = ccw.count - sizeof(features);
How about:
sch->curr_status.scsw.count = ccw_dstream_residual_count(>cds);

This also applies to other places.

>  ret = 0;
>  }
[...]

> @@ -501,21 +459,13 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
>  }
>  }
>  len = MIN(ccw.count, vdev->config_len);
> -hw_len = len;
>  if (!ccw.cda) {
>  ret = -EFAULT;
>  } else {
> -config = cpu_physical_memory_map(ccw.cda, _len, 0);
> -if (!config) {
> -ret = -EFAULT;
> -} else {
> -len = hw_len;
> -/* XXX config space endianness */
> -memcpy(vdev->config, config, len);
> -cpu_physical_memory_unmap(config, hw_len, 0, hw_len);
> +ret = ccw_dstream_read_buf(>cds, vdev->config, len);
> +if (!ret) {
Add a TODO here, and:

if (ccw_dstream_read_buf(>cds, vdev->config, len)) {
ret = -EFAULT;
} else {

}

>  virtio_bus_set_vdev_config(>bus, vdev->config);
>  sch->curr_status.scsw.count = ccw.count - len;
> -ret = 0;
>  }
>  }
>  break;
[...]

> @@ -714,13 +654,9 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
>  ret = -EFAULT;
>  break;
>  }
> -revinfo.revision =
> -address_space_lduw_be(_space_memory, ccw.cda,
> -  MEMTXATTRS_UNSPECIFIED, NULL);
> -revinfo.length =
> -address_space_lduw_be(_space_memory,
> -  ccw.cda + sizeof(revinfo.revision),
> -  MEMTXATTRS_UNSPECIFIED, NULL);
> +ccw_dstream_read_buf(>cds, , 4);
 ^
A magic number? O:)

> +be16_to_cpus();
> +be16_to_cpus();
>  if (ccw.count < len + revinfo.length ||
>  (check_len && ccw.count > len + revinfo.length)) {
>  ret = -EINVAL;
> -- 
> 2.13.5
> 

Otherwise, looks good.

-- 
Dong Jia Shi

Re: [Qemu-devel] [PATCH v2 3/4] virtio-ccw: use ccw data stream

[Cornelia Huck]

On Wed, 13 Sep 2017 13:50:28 +0200
Halil Pasic  wrote:

> Replace direct access which implicitly assumes no IDA
> or MIDA with the new ccw data stream interface which should
> cope with these transparently in the future.
> 
> Signed-off-by: Halil Pasic 


> @@ -488,7 +446,7 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
>  } else {
>  virtio_bus_get_vdev_config(>bus, vdev->config);
>  /* XXX config space endianness */
> -cpu_physical_memory_write(ccw.cda, vdev->config, len);
> +ccw_dstream_write_buf(>cds, vdev->config, len);
>  sch->curr_status.scsw.count = ccw.count - len;
>  ret = 0;
>  }
> @@ -501,21 +459,13 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
>  }
>  }
>  len = MIN(ccw.count, vdev->config_len);
> -hw_len = len;
>  if (!ccw.cda) {
>  ret = -EFAULT;
>  } else {
> -config = cpu_physical_memory_map(ccw.cda, _len, 0);
> -if (!config) {
> -ret = -EFAULT;
> -} else {
> -len = hw_len;
> -/* XXX config space endianness */
> -memcpy(vdev->config, config, len);
> -cpu_physical_memory_unmap(config, hw_len, 0, hw_len);
> +ret = ccw_dstream_read_buf(>cds, vdev->config, len);
> +if (!ret) {
>  virtio_bus_set_vdev_config(>bus, vdev->config);
>  sch->curr_status.scsw.count = ccw.count - len;
> -ret = 0;
>  }
>  }
>  break;

It feels a bit odd that you remove the stale XXX comment only for one
direction. Care to post a patch that removes them separately? Else I
can do that as well.

[I'd queue that patch in front of this patchset, but no need to resend
for that.]

[Qemu-devel] [PATCH v2 3/4] virtio-ccw: use ccw data stream

[Halil Pasic]

Replace direct access which implicitly assumes no IDA
or MIDA with the new ccw data stream interface which should
cope with these transparently in the future.

Signed-off-by: Halil Pasic 

---

v1 --> v2:
Removed todo comments on possible errno change as with
https://lists.nongnu.org/archive/html/qemu-devel/2017-09/msg02441.html
applied it does not matter any more.

Error handling: At the moment we ignore errors reported
by stream ops to keep the change minimal. An add-on
patch improving on this is to be expected later.
---
 hw/s390x/virtio-ccw.c | 156 +++---
 1 file changed, 46 insertions(+), 110 deletions(-)

diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
index b1976fdd19..a9baf6f7ab 100644
--- a/hw/s390x/virtio-ccw.c
+++ b/hw/s390x/virtio-ccw.c
@@ -287,49 +287,19 @@ static int virtio_ccw_handle_set_vq(SubchDev *sch, CCW1 
ccw, bool check_len,
 return -EFAULT;
 }
 if (is_legacy) {
-linfo.queue = address_space_ldq_be(_space_memory, ccw.cda,
-   MEMTXATTRS_UNSPECIFIED, NULL);
-linfo.align = address_space_ldl_be(_space_memory,
-   ccw.cda + sizeof(linfo.queue),
-   MEMTXATTRS_UNSPECIFIED,
-   NULL);
-linfo.index = address_space_lduw_be(_space_memory,
-ccw.cda + sizeof(linfo.queue)
-+ sizeof(linfo.align),
-MEMTXATTRS_UNSPECIFIED,
-NULL);
-linfo.num = address_space_lduw_be(_space_memory,
-  ccw.cda + sizeof(linfo.queue)
-  + sizeof(linfo.align)
-  + sizeof(linfo.index),
-  MEMTXATTRS_UNSPECIFIED,
-  NULL);
+ccw_dstream_read(>cds, linfo);
+be64_to_cpus();
+be32_to_cpus();
+be16_to_cpus();
+be16_to_cpus();
 ret = virtio_ccw_set_vqs(sch, NULL, );
 } else {
-info.desc = address_space_ldq_be(_space_memory, ccw.cda,
-   MEMTXATTRS_UNSPECIFIED, NULL);
-info.index = address_space_lduw_be(_space_memory,
-   ccw.cda + sizeof(info.desc)
-   + sizeof(info.res0),
-   MEMTXATTRS_UNSPECIFIED, NULL);
-info.num = address_space_lduw_be(_space_memory,
- ccw.cda + sizeof(info.desc)
- + sizeof(info.res0)
- + sizeof(info.index),
- MEMTXATTRS_UNSPECIFIED, NULL);
-info.avail = address_space_ldq_be(_space_memory,
-  ccw.cda + sizeof(info.desc)
-  + sizeof(info.res0)
-  + sizeof(info.index)
-  + sizeof(info.num),
-  MEMTXATTRS_UNSPECIFIED, NULL);
-info.used = address_space_ldq_be(_space_memory,
- ccw.cda + sizeof(info.desc)
- + sizeof(info.res0)
- + sizeof(info.index)
- + sizeof(info.num)
- + sizeof(info.avail),
- MEMTXATTRS_UNSPECIFIED, NULL);
+ccw_dstream_read(>cds, info);
+be64_to_cpus();
+be16_to_cpus();
+be16_to_cpus();
+be64_to_cpus();
+be64_to_cpus();
 ret = virtio_ccw_set_vqs(sch, , NULL);
 }
 sch->curr_status.scsw.count = 0;
@@ -342,15 +312,13 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
 VirtioRevInfo revinfo;
 uint8_t status;
 VirtioFeatDesc features;
-void *config;
 hwaddr indicators;
 VqConfigBlock vq_config;
 VirtioCcwDevice *dev = sch->driver_data;
 VirtIODevice *vdev = virtio_ccw_get_vdev(sch);
 bool check_len;
 int len;
-hwaddr hw_len;
-VirtioThinintInfo *thinint;
+VirtioThinintInfo thinint;
 
 if (!dev) {
 return -EINVAL;
@@ -394,11 +362,8 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
 } else {
 VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
 
-features.index = address_space_ldub(_space_memory,
-ccw.cda
-+ sizeof(features.features),
-