RE: [PATCH v5 15/15] iommu/vt-d: Support reporting nesting capability info

2020-07-20 Thread Liu, Yi L
Hi Eric,

> From: Auger Eric 
> Sent: Saturday, July 18, 2020 1:14 AM
> 
> Hi Yi,
> 
> Missing a proper commit message. You can comment on the fact you only
> support the case where all the physical iomms have the same CAP/ECAP MASKS

got it. will add it. it looks like the subject is straightforward, so I removed 
commit
message.

> 
> On 7/12/20 1:21 PM, Liu Yi L wrote:
> > Cc: Kevin Tian 
> > CC: Jacob Pan 
> > Cc: Alex Williamson 
> > Cc: Eric Auger 
> > Cc: Jean-Philippe Brucker 
> > Cc: Joerg Roedel 
> > Cc: Lu Baolu 
> > Signed-off-by: Liu Yi L 
> > Signed-off-by: Jacob Pan 
> > ---
> > v2 -> v3:
> > *) remove cap/ecap_mask in iommu_nesting_info.
> > ---
> >  drivers/iommu/intel/iommu.c | 81
> +++--
> >  include/linux/intel-iommu.h | 16 +
> >  2 files changed, 95 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> > index a9504cb..9f7ad1a 100644
> > --- a/drivers/iommu/intel/iommu.c
> > +++ b/drivers/iommu/intel/iommu.c
> > @@ -5659,12 +5659,16 @@ static inline bool iommu_pasid_support(void)
> >  static inline bool nested_mode_support(void)
> >  {
> > struct dmar_drhd_unit *drhd;
> > -   struct intel_iommu *iommu;
> > +   struct intel_iommu *iommu, *prev = NULL;
> > bool ret = true;
> >
> > rcu_read_lock();
> > for_each_active_iommu(iommu, drhd) {
> > -   if (!sm_supported(iommu) || !ecap_nest(iommu->ecap)) {
> > +   if (!prev)
> > +   prev = iommu;
> > +   if (!sm_supported(iommu) || !ecap_nest(iommu->ecap) ||
> > +   (VTD_CAP_MASK & (iommu->cap ^ prev->cap)) ||
> > +   (VTD_ECAP_MASK & (iommu->ecap ^ prev->ecap))) {
> > ret = false;
> > break;> }
> > @@ -6079,6 +6083,78 @@ intel_iommu_domain_set_attr(struct iommu_domain
> *domain,
> > return ret;
> >  }
> >
> > +static int intel_iommu_get_nesting_info(struct iommu_domain *domain,
> > +   struct iommu_nesting_info *info)
> > +{
> > +   struct dmar_domain *dmar_domain = to_dmar_domain(domain);
> > +   u64 cap = VTD_CAP_MASK, ecap = VTD_ECAP_MASK;
> > +   struct device_domain_info *domain_info;
> > +   struct iommu_nesting_info_vtd vtd;
> > +   unsigned long flags;
> > +   unsigned int size;
> > +
> > +   if (domain->type != IOMMU_DOMAIN_UNMANAGED ||
> > +   !(dmar_domain->flags & DOMAIN_FLAG_NESTING_MODE))
> > +   return -ENODEV;
> > +
> > +   if (!info)
> > +   return -EINVAL;
> > +
> > +   size = sizeof(struct iommu_nesting_info) +
> > +   sizeof(struct iommu_nesting_info_vtd);
> > +   /*
> > +* if provided buffer size is smaller than expected, should
> > +* return 0 and also the expected buffer size to caller.
> > +*/
> > +   if (info->size < size) {
> > +   info->size = size;
> > +   return 0;
> > +   }
> > +
> > +   spin_lock_irqsave(_domain_lock, flags);
> > +   /*
> > +* arbitrary select the first domain_info as all nesting
> > +* related capabilities should be consistent across iommu
> > +* units.
> > +*/
> > +   domain_info = list_first_entry(_domain->devices,
> > +  struct device_domain_info, link);
> > +   cap &= domain_info->iommu->cap;
> > +   ecap &= domain_info->iommu->ecap;
> > +   spin_unlock_irqrestore(_domain_lock, flags);
> > +
> > +   info->format = IOMMU_PASID_FORMAT_INTEL_VTD;
> > +   info->features = IOMMU_NESTING_FEAT_SYSWIDE_PASID |
> > +IOMMU_NESTING_FEAT_BIND_PGTBL |
> > +IOMMU_NESTING_FEAT_CACHE_INVLD;
> > +   info->addr_width = dmar_domain->gaw;
> > +   info->pasid_bits = ilog2(intel_pasid_max_id);
> > +   info->padding = 0;
> > +   vtd.flags = 0;
> > +   vtd.padding = 0;
> > +   vtd.cap_reg = cap;
> > +   vtd.ecap_reg = ecap;
> > +
> > +   memcpy(info->data, , sizeof(vtd));
> > +   return 0;
> > +}
> > +
> > +static int intel_iommu_domain_get_attr(struct iommu_domain *domain,
> > +  enum iommu_attr attr, void *data)
> > +{
> > +   switch (attr) {
> > +   case DOMAIN_ATTR_NESTING:
> > +   {
> > +   struct iommu_nesting_info *info =
> > +   (struct iommu_nesting_info *)data;
> > +
> > +   return intel_iommu_get_nesting_info(domain, info);
> > +   }
> > +   default:
> > +   return -ENODEV;
> -ENOENT?

arm_smmu_domain_get_attr() is using -ENODEV, so I used the same. I can
modify it if -ENOENT is better. :-)

Regards,
Yi Liu

> > +   }
> > +}
> > +
> >  /*
> >   * Check that the device does not live on an external facing PCI port that 
> > is
> >   * marked as untrusted. Such devices should not be able to apply quirks and
> > @@ -6101,6 +6177,7 @@ const struct iommu_ops intel_iommu_ops = {
> > .domain_alloc   = intel_iommu_domain_alloc,
> > .domain_free= intel_iommu_domain_free,
> > .domain_set_attr 

Re: [PATCH v5 15/15] iommu/vt-d: Support reporting nesting capability info

2020-07-17 Thread Auger Eric
Hi Yi,

Missing a proper commit message. You can comment on the fact you only
support the case where all the physical iomms have the same CAP/ECAP MASKS

On 7/12/20 1:21 PM, Liu Yi L wrote:
> Cc: Kevin Tian 
> CC: Jacob Pan 
> Cc: Alex Williamson 
> Cc: Eric Auger 
> Cc: Jean-Philippe Brucker 
> Cc: Joerg Roedel 
> Cc: Lu Baolu 
> Signed-off-by: Liu Yi L 
> Signed-off-by: Jacob Pan 
> ---
> v2 -> v3:
> *) remove cap/ecap_mask in iommu_nesting_info.
> ---
>  drivers/iommu/intel/iommu.c | 81 
> +++--
>  include/linux/intel-iommu.h | 16 +
>  2 files changed, 95 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index a9504cb..9f7ad1a 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -5659,12 +5659,16 @@ static inline bool iommu_pasid_support(void)
>  static inline bool nested_mode_support(void)
>  {
>   struct dmar_drhd_unit *drhd;
> - struct intel_iommu *iommu;
> + struct intel_iommu *iommu, *prev = NULL;
>   bool ret = true;
>  
>   rcu_read_lock();
>   for_each_active_iommu(iommu, drhd) {
> - if (!sm_supported(iommu) || !ecap_nest(iommu->ecap)) {
> + if (!prev)
> + prev = iommu;
> + if (!sm_supported(iommu) || !ecap_nest(iommu->ecap) ||
> + (VTD_CAP_MASK & (iommu->cap ^ prev->cap)) ||
> + (VTD_ECAP_MASK & (iommu->ecap ^ prev->ecap))) {
>   ret = false;
>   break;> }
> @@ -6079,6 +6083,78 @@ intel_iommu_domain_set_attr(struct iommu_domain 
> *domain,
>   return ret;
>  }
>  
> +static int intel_iommu_get_nesting_info(struct iommu_domain *domain,
> + struct iommu_nesting_info *info)
> +{
> + struct dmar_domain *dmar_domain = to_dmar_domain(domain);
> + u64 cap = VTD_CAP_MASK, ecap = VTD_ECAP_MASK;
> + struct device_domain_info *domain_info;
> + struct iommu_nesting_info_vtd vtd;
> + unsigned long flags;
> + unsigned int size;
> +
> + if (domain->type != IOMMU_DOMAIN_UNMANAGED ||
> + !(dmar_domain->flags & DOMAIN_FLAG_NESTING_MODE))
> + return -ENODEV;
> +
> + if (!info)
> + return -EINVAL;
> +
> + size = sizeof(struct iommu_nesting_info) +
> + sizeof(struct iommu_nesting_info_vtd);
> + /*
> +  * if provided buffer size is smaller than expected, should
> +  * return 0 and also the expected buffer size to caller.
> +  */
> + if (info->size < size) {
> + info->size = size;
> + return 0;
> + }
> +
> + spin_lock_irqsave(_domain_lock, flags);
> + /*
> +  * arbitrary select the first domain_info as all nesting
> +  * related capabilities should be consistent across iommu
> +  * units.
> +  */
> + domain_info = list_first_entry(_domain->devices,
> +struct device_domain_info, link);
> + cap &= domain_info->iommu->cap;
> + ecap &= domain_info->iommu->ecap;
> + spin_unlock_irqrestore(_domain_lock, flags);
> +
> + info->format = IOMMU_PASID_FORMAT_INTEL_VTD;
> + info->features = IOMMU_NESTING_FEAT_SYSWIDE_PASID |
> +  IOMMU_NESTING_FEAT_BIND_PGTBL |
> +  IOMMU_NESTING_FEAT_CACHE_INVLD;
> + info->addr_width = dmar_domain->gaw;
> + info->pasid_bits = ilog2(intel_pasid_max_id);
> + info->padding = 0;
> + vtd.flags = 0;
> + vtd.padding = 0;
> + vtd.cap_reg = cap;
> + vtd.ecap_reg = ecap;
> +
> + memcpy(info->data, , sizeof(vtd));
> + return 0;
> +}
> +
> +static int intel_iommu_domain_get_attr(struct iommu_domain *domain,
> +enum iommu_attr attr, void *data)
> +{
> + switch (attr) {
> + case DOMAIN_ATTR_NESTING:
> + {
> + struct iommu_nesting_info *info =
> + (struct iommu_nesting_info *)data;
> +
> + return intel_iommu_get_nesting_info(domain, info);
> + }
> + default:
> + return -ENODEV;
-ENOENT?
> + }
> +}
> +
>  /*
>   * Check that the device does not live on an external facing PCI port that is
>   * marked as untrusted. Such devices should not be able to apply quirks and
> @@ -6101,6 +6177,7 @@ const struct iommu_ops intel_iommu_ops = {
>   .domain_alloc   = intel_iommu_domain_alloc,
>   .domain_free= intel_iommu_domain_free,
>   .domain_set_attr= intel_iommu_domain_set_attr,
> + .domain_get_attr= intel_iommu_domain_get_attr,
>   .attach_dev = intel_iommu_attach_device,
>   .detach_dev = intel_iommu_detach_device,
>   .aux_attach_dev = intel_iommu_aux_attach_device,
> diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
> index 18f292e..c4ed0d4 100644
> ---