Re: [PATCH 05/12] hw/virtio: Add support for apple virtio-blk

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 16/6/23 13:48, Kevin Wolf wrote:
> Am 15.06.2023 um 00:56 hat Alexander Graf geschrieben:
>> Apple has its own virtio-blk PCI device ID where it deviates from the
>> official virtio-pci spec slightly: It puts a new "apple type"
>> field at a static offset in config space and introduces a new discard
>> command.
> 
> In other words, it's a different device. We shouldn't try to
> differentiate only with a property, but actually model it as a separate
> device.

I was thinking of qdev inheritance:

#define TYPE_VIRTIO_BLK_PCI_APPLE "virtio-blk-pci-apple"
OBJECT_DECLARE_SIMPLE_TYPE(VirtIOBlkPCIApple, TYPE_VIRTIO_BLK_PCI_APPLE)

struct VirtIOBlkPCIApple {
     VirtIOBlkPCI parent_obj;
};

and add an optional custom handler in VirtioDeviceClass to handle the
VIRTIO_BLK_T_APPLE1 case.

>> This patch adds a new qdev property called "apple-type" to virtio-blk-pci.
>> When that property is set, we assume the virtio-blk device is an Apple one
>> of the specific type and act accordingly.
> 
> Do we have any information on what the number in "apple-type" actually
> means or do we have to treat it as a black box?
> 
>> Signed-off-by: Alexander Graf <graf@amazon.com>
>> ---
>>   hw/block/virtio-blk.c                       | 23 +++++++++++++++++++++
>>   hw/virtio/virtio-blk-pci.c                  |  7 +++++++
>>   include/hw/pci/pci_ids.h                    |  1 +
>>   include/hw/virtio/virtio-blk.h              |  1 +
>>   include/standard-headers/linux/virtio_blk.h |  3 +++
>>   5 files changed, 35 insertions(+)