Re: [PATCH v3 5/7] iommu/riscv: Device directory management.

[Baolu Lu]

On 5/1/24 4:01 AM, Tomasz Jeznach wrote:
> @@ -128,6 +489,7 @@ void riscv_iommu_remove(struct riscv_iommu_device *iommu)
>   {
>   	iommu_device_unregister(&iommu->iommu);
>   	iommu_device_sysfs_remove(&iommu->iommu);
> +	riscv_iommu_iodir_set_mode(iommu, RISCV_IOMMU_DDTP_MODE_OFF);
>   }
>   
>   int riscv_iommu_init(struct riscv_iommu_device *iommu)
> @@ -138,12 +500,13 @@ int riscv_iommu_init(struct riscv_iommu_device *iommu)
>   	if (rc)
>   		return dev_err_probe(iommu->dev, rc, "unexpected device state\n");
>   
> -	/*
> -	 * Placeholder for a complete IOMMU device initialization.
> -	 * For now, only bare minimum: enable global identity mapping mode and register sysfs.
> -	 */
> -	riscv_iommu_writeq(iommu, RISCV_IOMMU_REG_DDTP,
> -			   FIELD_PREP(RISCV_IOMMU_DDTP_MODE, RISCV_IOMMU_DDTP_MODE_BARE));
> +	rc = riscv_iommu_iodir_alloc(iommu);
> +	if (rc)
> +		goto err_init;
> +
> +	rc = riscv_iommu_iodir_set_mode(iommu, RISCV_IOMMU_DDTP_MODE_MAX);
> +	if (rc)
> +		goto err_init;
>   
>   	rc = iommu_device_sysfs_add(&iommu->iommu, NULL, NULL, "riscv-iommu@%s",
>   				    dev_name(iommu->dev));

The device directory root page might be allocated in
riscv_iommu_iodir_alloc(),

+	if (!iommu->ddt_root) {
+		iommu->ddt_root = riscv_iommu_get_pages(iommu, 0);
+		iommu->ddt_phys = __pa(iommu->ddt_root);
+	}

But I didn't find any place to free it in the error paths. Did I
overlook anything?

Best regards,
baolu