Re: [PATCH 02/06] iommu/ipmmu-vmsa: Convert to dev_data

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Magnus,

Thank you for the patch.

On Tuesday 15 December 2015 21:02:30 Magnus Damm wrote:
> From: Magnus Damm <damm+renesas@opensource.se>
> 
> Rename ipmmu_vmsa_archdata to ipmmu_vmsa_dev_data to avoid
> confusion when using the driver on multiple architectures.

I'm sorry but this patches makes the driver more confusing to me. archdata is 
a well established concept for IOMMU on ARM, I don't see how hiding help would 
help.

> The data now stored in ipmmu_vmsa_dev_data is used to point
> various on-chip devices to the actual IPMMU instances.
> 
> Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
> ---
> 
>  drivers/iommu/ipmmu-vmsa.c |   58 +++++++++++++++++++++++++----------------
>  1 file changed, 36 insertions(+), 22 deletions(-)
> 
> --- 0003/drivers/iommu/ipmmu-vmsa.c
> +++ work/drivers/iommu/ipmmu-vmsa.c	2015-12-15 13:16:27.160513000 +0900
> @@ -47,7 +47,7 @@ struct ipmmu_vmsa_domain {
>  	spinlock_t lock;			/* Protects mappings */
>  };
> 
> -struct ipmmu_vmsa_archdata {
> +struct ipmmu_vmsa_dev_data {
>  	struct ipmmu_vmsa_device *mmu;
>  	unsigned int *utlbs;
>  	unsigned int num_utlbs;
> @@ -182,6 +182,20 @@ static struct ipmmu_vmsa_domain *to_vmsa
>  #define IMUASID_ASID0_SHIFT		0
> 
>  /* ------------------------------------------------------------------------
> + * Consumer device side private data handling
> + */
> +
> +static struct ipmmu_vmsa_dev_data *get_dev_data(struct device *dev)
> +{
> +	return dev->archdata.iommu;
> +}
> +
> +static void set_dev_data(struct device *dev, struct ipmmu_vmsa_dev_data
> *data)
> +{
> +	dev->archdata.iommu = data;
> +}
> +
> +/* ------------------------------------------------------------------------
>   * Read/Write Access
>   */
> 
> @@ -485,8 +499,8 @@ static void ipmmu_domain_free(struct iom
>  static int ipmmu_attach_device(struct iommu_domain *io_domain,
>  			       struct device *dev)
>  {
> -	struct ipmmu_vmsa_archdata *archdata = dev->archdata.iommu;
> -	struct ipmmu_vmsa_device *mmu = archdata->mmu;
> +	struct ipmmu_vmsa_dev_data *dev_data = get_dev_data(dev);
> +	struct ipmmu_vmsa_device *mmu = dev_data->mmu;
>  	struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
>  	unsigned long flags;
>  	unsigned int i;
> @@ -518,8 +532,8 @@ static int ipmmu_attach_device(struct io
>  	if (ret < 0)
>  		return ret;
> 
> -	for (i = 0; i < archdata->num_utlbs; ++i)
> -		ipmmu_utlb_enable(domain, archdata->utlbs[i]);
> +	for (i = 0; i < dev_data->num_utlbs; ++i)
> +		ipmmu_utlb_enable(domain, dev_data->utlbs[i]);
> 
>  	return 0;
>  }
> @@ -527,12 +541,12 @@ static int ipmmu_attach_device(struct io
>  static void ipmmu_detach_device(struct iommu_domain *io_domain,
>  				struct device *dev)
>  {
> -	struct ipmmu_vmsa_archdata *archdata = dev->archdata.iommu;
> +	struct ipmmu_vmsa_dev_data *dev_data = get_dev_data(dev);
>  	struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
>  	unsigned int i;
> 
> -	for (i = 0; i < archdata->num_utlbs; ++i)
> -		ipmmu_utlb_disable(domain, archdata->utlbs[i]);
> +	for (i = 0; i < dev_data->num_utlbs; ++i)
> +		ipmmu_utlb_disable(domain, dev_data->utlbs[i]);
> 
>  	/*
>  	 * TODO: Optimize by disabling the context when no device is attached.
> @@ -595,7 +609,7 @@ static int ipmmu_find_utlbs(struct ipmmu
> 
>  static int ipmmu_add_device(struct device *dev)
>  {
> -	struct ipmmu_vmsa_archdata *archdata;
> +	struct ipmmu_vmsa_dev_data *dev_data = get_dev_data(dev);
>  	struct ipmmu_vmsa_device *mmu;
>  	struct iommu_group *group = NULL;
>  	unsigned int *utlbs;
> @@ -603,7 +617,7 @@ static int ipmmu_add_device(struct devic
>  	int num_utlbs;
>  	int ret = -ENODEV;
> 
> -	if (dev->archdata.iommu) {
> +	if (dev_data) {
>  		dev_warn(dev, "IOMMU driver already assigned to device %s\n",
>  			 dev_name(dev));
>  		return -EINVAL;
> @@ -662,16 +676,16 @@ static int ipmmu_add_device(struct devic
>  		goto error;
>  	}
> 
> -	archdata = kzalloc(sizeof(*archdata), GFP_KERNEL);
> -	if (!archdata) {
> +	dev_data = kzalloc(sizeof(*dev_data), GFP_KERNEL);
> +	if (!dev_data) {
>  		ret = -ENOMEM;
>  		goto error;
>  	}
> 
> -	archdata->mmu = mmu;
> -	archdata->utlbs = utlbs;
> -	archdata->num_utlbs = num_utlbs;
> -	dev->archdata.iommu = archdata;
> +	dev_data->mmu = mmu;
> +	dev_data->utlbs = utlbs;
> +	dev_data->num_utlbs = num_utlbs;
> +	set_dev_data(dev, dev_data);
> 
>  	/*
>  	 * Create the ARM mapping, used by the ARM DMA mapping core to allocate
> @@ -708,10 +722,10 @@ static int ipmmu_add_device(struct devic
>  error:
>  	arm_iommu_release_mapping(mmu->mapping);
> 
> -	kfree(dev->archdata.iommu);
> +	kfree(dev_data);
>  	kfree(utlbs);
> 
> -	dev->archdata.iommu = NULL;
> +	set_dev_data(dev, NULL);
> 
>  	if (!IS_ERR_OR_NULL(group))
>  		iommu_group_remove_device(dev);
> @@ -721,15 +735,15 @@ error:
> 
>  static void ipmmu_remove_device(struct device *dev)
>  {
> -	struct ipmmu_vmsa_archdata *archdata = dev->archdata.iommu;
> +	struct ipmmu_vmsa_dev_data *dev_data = get_dev_data(dev);
> 
>  	arm_iommu_detach_device(dev);
>  	iommu_group_remove_device(dev);
> 
> -	kfree(archdata->utlbs);
> -	kfree(archdata);
> +	kfree(dev_data->utlbs);
> +	kfree(dev_data);
> 
> -	dev->archdata.iommu = NULL;
> +	set_dev_data(dev, NULL);
>  }
> 
>  static const struct iommu_ops ipmmu_ops = {

-- 
Regards,

Laurent Pinchart