Re: [PATCH 02/10] vDPA: report virtio-block max segment size to user space

["Zhu, Lingshan" <lingshan.zhu@intel.com>]

On 3/20/2024 12:04 AM, Stefano Garzarella wrote:
> On Mon, Feb 19, 2024 at 02:55:58AM +0800, Zhu Lingshan wrote:
>> This commit allows reporting the max size of any
>> single segment of virtio-block devices to user space.
>>
>> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>> ---
>> drivers/vdpa/vdpa.c       | 17 +++++++++++++++++
>> include/uapi/linux/vdpa.h |  1 +
>> 2 files changed, 18 insertions(+)
>>
>> diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
>> index d5ccb618de2b..ee1472d32b0d 100644
>> --- a/drivers/vdpa/vdpa.c
>> +++ b/drivers/vdpa/vdpa.c
>> @@ -956,6 +956,20 @@ vdpa_dev_blk_capacity_config_fill(struct sk_buff 
>> *msg,
>>                  val_u64, VDPA_ATTR_PAD);
>> }
>>
>> +static int
>> +vdpa_dev_blk_seg_size_config_fill(struct sk_buff *msg, u64 features,
>> +                  const struct virtio_blk_config *config)
>> +{
>> +    u32 val_u32;
>> +
>> +    if ((features & BIT_ULL(VIRTIO_BLK_F_SIZE_MAX)) == 0)
>> +        return 0;
>> +
>> +    val_u32 = __virtio32_to_cpu(true, config->size_max);
>> +
>> +    return nla_put_u32(msg, VDPA_ATTR_DEV_BLK_CFG_SEG_SIZE, val_u32);
>
> Should we call this VDPA_ATTR_DEV_BLK_CFG_SIZE_MAX ?
I have tried this before, but this macro is too long causing a odd 
format in the header file.

I can change this since you point this out. This is uapi means we should 
merge the
fix during the RC release before 6.9 official.

@MST, does the process work for you?
>
>> +}
>> +
>> static int vdpa_dev_blk_config_fill(struct vdpa_device *vdev,
>>                     struct sk_buff *msg)
>> {
>> @@ -973,6 +987,9 @@ static int vdpa_dev_blk_config_fill(struct 
>> vdpa_device *vdev,
>>     if (vdpa_dev_blk_capacity_config_fill(msg, &config))
>>         return -EMSGSIZE;
>>
>> +    if (vdpa_dev_blk_seg_size_config_fill(msg, features_device, 
>> &config))
>> +        return -EMSGSIZE;
>> +
>>     return 0;
>> }
>>
>> diff --git a/include/uapi/linux/vdpa.h b/include/uapi/linux/vdpa.h
>> index 1bf69226cb96..586bce3c906a 100644
>> --- a/include/uapi/linux/vdpa.h
>> +++ b/include/uapi/linux/vdpa.h
>> @@ -57,6 +57,7 @@ enum vdpa_attr {
>>     VDPA_ATTR_DEV_FEATURES,                 /* u64 */
>>
>>     VDPA_ATTR_DEV_BLK_CFG_CAPACITY,        /* u64 */
>> +    VDPA_ATTR_DEV_BLK_CFG_SEG_SIZE,        /* u32 */
>>
>>     /* new attributes must be added above here */
>>     VDPA_ATTR_MAX,
>> -- 
>> 2.39.3
>>
>>
>
>