Re: [PATCH v14 07/13] iommu/smmuv3: Implement cache_invalidate

From: Auger Eric
Date: Thu Apr 01 2021 - 14:48:22 EST


Hi Zenghui,

On 4/1/21 8:11 AM, Zenghui Yu wrote:
> Hi Eric,
>
> On 2021/2/24 4:56, Eric Auger wrote:
>> +static int
>> +arm_smmu_cache_invalidate(struct iommu_domain *domain, struct device
>> *dev,
>> +              struct iommu_cache_invalidate_info *inv_info)
>> +{
>> +    struct arm_smmu_cmdq_ent cmd = {.opcode = CMDQ_OP_TLBI_NSNH_ALL};
>> +    struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
>> +    struct arm_smmu_device *smmu = smmu_domain->smmu;
>> +
>> +    if (smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
>> +        return -EINVAL;
>> +
>> +    if (!smmu)
>> +        return -EINVAL;
>> +
>> +    if (inv_info->version != IOMMU_CACHE_INVALIDATE_INFO_VERSION_1)
>> +        return -EINVAL;
>> +
>> +    if (inv_info->cache & IOMMU_CACHE_INV_TYPE_PASID ||
>
> I didn't find any code where we would emulate the CFGI_CD{_ALL} commands
> for guest and invalidate the stale CD entries on the physical side. Is
> PASID-cache type designed for that effect?
Yes it is. PASID-cache matches the CD table.
>
>> +        inv_info->cache & IOMMU_CACHE_INV_TYPE_DEV_IOTLB) {
>> +        return -ENOENT;
>> +    }
>> +
>> +    if (!(inv_info->cache & IOMMU_CACHE_INV_TYPE_IOTLB))
>> +        return -EINVAL;
>> +
>> +    /* IOTLB invalidation */
>> +
>> +    switch (inv_info->granularity) {
>> +    case IOMMU_INV_GRANU_PASID:
>> +    {
>> +        struct iommu_inv_pasid_info *info =
>> +            &inv_info->granu.pasid_info;
>> +
>> +        if (info->flags & IOMMU_INV_ADDR_FLAGS_PASID)
>> +            return -ENOENT;
>> +        if (!(info->flags & IOMMU_INV_PASID_FLAGS_ARCHID))
>> +            return -EINVAL;
>> +
>> +        __arm_smmu_tlb_inv_context(smmu_domain, info->archid);
>> +        return 0;
>> +    }
>> +    case IOMMU_INV_GRANU_ADDR:
>> +    {
>> +        struct iommu_inv_addr_info *info = &inv_info->granu.addr_info;
>> +        size_t size = info->nb_granules * info->granule_size;
>> +        bool leaf = info->flags & IOMMU_INV_ADDR_FLAGS_LEAF;
>> +
>> +        if (info->flags & IOMMU_INV_ADDR_FLAGS_PASID)
>> +            return -ENOENT;
>> +
>> +        if (!(info->flags & IOMMU_INV_ADDR_FLAGS_ARCHID))
>> +            break;
>> +
>> +        arm_smmu_tlb_inv_range_domain(info->addr, size,
>> +                          info->granule_size, leaf,
>> +                          info->archid, smmu_domain);
>> +
>> +        arm_smmu_cmdq_issue_sync(smmu);
>
> There is no need to issue one more SYNC.
Hum yes I did not notice it was made by the arm_smmu_cmdq_issue_cmdlist()

Thanks!

Eric
>