Re: [PATCH v2 10/22] iommufd/viommmu: Add IOMMUFD_CMD_VCMDQ_ALLOC ioctl

[Baolu Lu]

On 4/26/25 13:58, Nicolin Chen wrote:

diff --git a/drivers/iommu/iommufd/viommu.c b/drivers/iommu/iommufd/viommu.c
index a65153458a26..02a111710ffe 100644
--- a/drivers/iommu/iommufd/viommu.c
+++ b/drivers/iommu/iommufd/viommu.c
@@ -170,3 +170,97 @@ int iommufd_vdevice_alloc_ioctl(struct iommufd_ucmd *ucmd)
        iommufd_put_object(ucmd->ictx, &viommu->obj);
        return rc;
  }
+
+void iommufd_vcmdq_destroy(struct iommufd_object *obj)
+{
+       struct iommufd_vcmdq *vcmdq =
+               container_of(obj, struct iommufd_vcmdq, obj);
+       struct iommufd_viommu *viommu = vcmdq->viommu;
+
+       if (viommu->ops->vcmdq_destroy)
+               viommu->ops->vcmdq_destroy(vcmdq);
+       iopt_unpin_pages(&viommu->hwpt->ioas->iopt, vcmdq->addr, vcmdq->length);
+       refcount_dec(&viommu->obj.users);
+}
+
+int iommufd_vcmdq_alloc_ioctl(struct iommufd_ucmd *ucmd)
+{
+       struct iommu_vcmdq_alloc *cmd = ucmd->cmd;
+       struct iommufd_viommu *viommu;
+       struct iommufd_vcmdq *vcmdq;
+       struct page **pages;
+       int max_npages, i;
+       dma_addr_t end;
+       int rc;
+
+       if (cmd->flags || cmd->type == IOMMU_VCMDQ_TYPE_DEFAULT)

I don't follow the check of 'cmd->type == IOMMU_VCMDQ_TYPE_DEFAULT'
here. My understanding is that it states that "other values of type are
not supported". If so, shouldn't it be,

        if (cmd->flags || cmd->type != IOMMU_VCMDQ_TYPE_DEFAULT)

?

+               return -EOPNOTSUPP;
+       if (!cmd->addr || !cmd->length)
+               return -EINVAL;
+       if (check_add_overflow(cmd->addr, cmd->length - 1, &end))
+               return -EOVERFLOW;

Thanks,
baolu