I feel like it would be easier to review if the first 4 patches were squashed together, but that’s not a big deal.
For this one: Reviewed-by: Raphael Norwitz <raphael.norw...@nutanix.com> On Fri, Aug 26, 2022 at 05:32:41PM +0300, Daniil Tatianin wrote: > This is the first step towards moving all device config size calculation > logic into the virtio core code. In particular, this adds a struct that > contains all the necessary information for common virtio code to be able > to calculate the final config size for a device. This is expected to be > used with the new virtio_get_config_size helper, which calculates the > final length based on the provided host features. > > This builds on top of already existing code like VirtIOFeature and > virtio_feature_get_config_size(), but adds additional fields, as well as > sanity checking so that device-specifc code doesn't have to duplicate it. > > An example usage would be: > > static const VirtIOFeature dev_features[] = { > {.flags = 1ULL << FEATURE_1_BIT, > .end = endof(struct virtio_dev_config, feature_1)}, > {.flags = 1ULL << FEATURE_2_BIT, > .end = endof(struct virtio_dev_config, feature_2)}, > {} > }; > > static const VirtIOConfigSizeParams dev_cfg_size_params = { > .min_size = DEV_BASE_CONFIG_SIZE, > .max_size = sizeof(struct virtio_dev_config), > .feature_sizes = dev_features > }; > > // code inside my_dev_device_realize() > size_t config_size = virtio_get_config_size(&dev_cfg_size_params, > host_features); > virtio_init(vdev, VIRTIO_ID_MYDEV, config_size); > > Currently every device is expected to write its own boilerplate from the > example above in device_realize(), however, the next step of this > transition is moving VirtIOConfigSizeParams into VirtioDeviceClass, > so that it can be done automatically by the virtio initialization code. > > Signed-off-by: Daniil Tatianin <d-tatia...@yandex-team.ru> > --- > hw/virtio/virtio.c | 17 +++++++++++++++++ > include/hw/virtio/virtio.h | 9 +++++++++ > 2 files changed, 26 insertions(+) > > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > index 5d607aeaa0..8518382025 100644 > --- a/hw/virtio/virtio.c > +++ b/hw/virtio/virtio.c > @@ -3014,6 +3014,23 @@ size_t virtio_feature_get_config_size(const > VirtIOFeature *feature_sizes, > return config_size; > } > > +size_t virtio_get_config_size(const VirtIOConfigSizeParams *params, > + uint64_t host_features) > +{ > + size_t config_size = params->min_size; > + const VirtIOFeature *feature_sizes = params->feature_sizes; > + size_t i; > + > + for (i = 0; feature_sizes[i].flags != 0; i++) { > + if (host_features & feature_sizes[i].flags) { > + config_size = MAX(feature_sizes[i].end, config_size); > + } > + } > + > + assert(config_size <= params->max_size); > + return config_size; > +} > + > int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id) > { > int i, ret; > diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h > index db1c0ddf6b..1991c58d9b 100644 > --- a/include/hw/virtio/virtio.h > +++ b/include/hw/virtio/virtio.h > @@ -44,6 +44,15 @@ typedef struct VirtIOFeature { > size_t end; > } VirtIOFeature; > > +typedef struct VirtIOConfigSizeParams { > + size_t min_size; > + size_t max_size; > + const VirtIOFeature *feature_sizes; > +} VirtIOConfigSizeParams; > + > +size_t virtio_get_config_size(const VirtIOConfigSizeParams *params, > + uint64_t host_features); > + > size_t virtio_feature_get_config_size(const VirtIOFeature *features, > uint64_t host_features); > > -- > 2.25.1 >