Re: [PATCH v6 06/07] iommu/ipmmu-vmsa: ARM and ARM64 archdata access

Robin Murphy
2016-10-21T17:33:03Z

Hi Magnus,

On 20/10/16 00:36, Magnus Damm wrote:
> From: Magnus Damm <damm+renesas@opensource.se>
>
> Not all architectures have an iommu member in their archdata, so
> use #ifdefs support build wit COMPILE_TEST on any architecture.

As an alternative to this we could now use iommu_fwspec in place of the
custom ipmmu_vmsa_archdata - that's deliberately
architecture-independent. I converted the Mediatek drivers[1] as an
example to stand separately from the big SMMU rework, as those are the
ones I'm most familiar with, but it looks like the IPMMU is a similarly
perfect fit.

Of course, that could always come afterwards as a cleanup - I wouldn't
consider it a blocker at this point - but it does look like it might
simplify some of the code being moved around in this series if it were
to be done beforehand.

Robin.

[1]:http://www.mail-archive.com/iommu@lists.linux-foundation.org/msg14577.html

>
> Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
> Reviewed-by: Joerg Roedel <jroedel@suse.de>
> ---
>
> Changes since V5:
> - None
>
> Changes since V4:
> - None
>
> Changes since V3:
> - New patch
>
> drivers/iommu/ipmmu-vmsa.c | 37 +++++++++++++++++++++++++++----------
> 1 file changed, 27 insertions(+), 10 deletions(-)
>
> --- 0012/drivers/iommu/ipmmu-vmsa.c
> +++ work/drivers/iommu/ipmmu-vmsa.c 2016-09-20 21:59:21.690607110 +0900
> @@ -70,6 +70,25 @@ static struct ipmmu_vmsa_domain *to_vmsa
> return container_of(dom, struct ipmmu_vmsa_domain, io_domain);
> }
>
> +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64)
> +static struct ipmmu_vmsa_archdata *to_archdata(struct device *dev)
> +{
> + return dev->archdata.iommu;
> +}
> +static void set_archdata(struct device *dev, struct ipmmu_vmsa_archdata *p)
> +{
> + dev->archdata.iommu = p;
> +}
> +#else
> +static struct ipmmu_vmsa_archdata *to_archdata(struct device *dev)
> +{
> + return NULL;
> +}
> +static void set_archdata(struct device *dev, struct ipmmu_vmsa_archdata *p)
> +{
> +}
> +#endif
> +
> #define TLB_LOOP_TIMEOUT 100 /* 100us */
>
> /* -----------------------------------------------------------------------------
> @@ -539,7 +558,7 @@ 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_archdata *archdata = to_archdata(dev);
> struct ipmmu_vmsa_device *mmu = archdata->mmu;
> struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
> unsigned long flags;
> @@ -581,7 +600,7 @@ 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_archdata *archdata = to_archdata(dev);
> struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
> unsigned int i;
>
> @@ -701,7 +720,7 @@ static int ipmmu_init_platform_device(st
> archdata->mmu = mmu;
> archdata->utlbs = utlbs;
> archdata->num_utlbs = num_utlbs;
> - dev->archdata.iommu = archdata;
> + set_archdata(dev, archdata);
> return 0;
>
> error:
> @@ -713,12 +732,11 @@ error:
>
> static int ipmmu_add_device(struct device *dev)
> {
> - struct ipmmu_vmsa_archdata *archdata;
> struct ipmmu_vmsa_device *mmu = NULL;
> struct iommu_group *group;
> int ret;
>
> - if (dev->archdata.iommu) {
> + if (to_archdata(dev)) {
> dev_warn(dev, "IOMMU driver already assigned to device %s\n",
> dev_name(dev));
> return -EINVAL;
> @@ -754,8 +772,7 @@ static int ipmmu_add_device(struct devic
> * - Make the mapping size configurable ? We currently use a 2GB mapping
> * at a 1GB offset to ensure that NULL VAs will fault.
> */
> - archdata = dev->archdata.iommu;
> - mmu = archdata->mmu;
> + mmu = to_archdata(dev)->mmu;
> if (!mmu->mapping) {
> struct dma_iommu_mapping *mapping;
>
> @@ -783,7 +800,7 @@ error:
> if (mmu)
> arm_iommu_release_mapping(mmu->mapping);
>
> - dev->archdata.iommu = NULL;
> + set_archdata(dev, NULL);
>
> if (!IS_ERR_OR_NULL(group))
> iommu_group_remove_device(dev);
> @@ -793,7 +810,7 @@ error:
>
> static void ipmmu_remove_device(struct device *dev)
> {
> - struct ipmmu_vmsa_archdata *archdata = dev->archdata.iommu;
> + struct ipmmu_vmsa_archdata *archdata = to_archdata(dev);
>
> arm_iommu_detach_device(dev);
> iommu_group_remove_device(dev);
> @@ -801,7 +818,7 @@ static void ipmmu_remove_device(struct d
> kfree(archdata->utlbs);
> kfree(archdata);
>
> - dev->archdata.iommu = NULL;
> + set_archdata(dev, NULL);
> }
>
> static struct iommu_domain *ipmmu_domain_alloc(unsigned type)
>