diff mbox series

[v5,01/19] iommu: Add IOMMU_CAP_ENFORCE_CACHE_COHERENCY

Message ID 1-v5-4001c2997bd0+30c-iommufd_jgg@nvidia.com (mailing list archive)
State Not Applicable
Headers show
Series IOMMUFD Generic interface | expand

Checks

Context Check Description
netdev/tree_selection success Not a local patch

Commit Message

Jason Gunthorpe Nov. 16, 2022, 9 p.m. UTC 
This queries if a domain linked to a device should expect to support
enforce_cache_coherency() so iommufd can negotiate the rules for when a
domain should be shared or not.

For iommufd a device that declares IOMMU_CAP_ENFORCE_CACHE_COHERENCY will
not be attached to a domain that does not support it.

Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Yi Liu <yi.l.liu@intel.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---
 drivers/iommu/amd/iommu.c   |  2 ++
 drivers/iommu/intel/iommu.c | 16 +++++++++++-----
 include/linux/iommu.h       |  5 +++++
 3 files changed, 18 insertions(+), 5 deletions(-)

Comments

Yi Liu Nov. 23, 2022, 8:30 a.m. UTC | #1 
On 2022/11/17 05:00, Jason Gunthorpe wrote:
> This queries if a domain linked to a device should expect to support
> enforce_cache_coherency() so iommufd can negotiate the rules for when a
> domain should be shared or not.
> 
> For iommufd a device that declares IOMMU_CAP_ENFORCE_CACHE_COHERENCY will
> not be attached to a domain that does not support it.
> 
> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> Tested-by: Nicolin Chen <nicolinc@nvidia.com>
> Tested-by: Yi Liu <yi.l.liu@intel.com>
> Tested-by: Lixiao Yang <lixiao.yang@intel.com>
> Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>

looks like Yu He's test-by was missed. :-) She has given it in below link.

https://lore.kernel.org/kvm/DM6PR11MB268429C4986C7808760CCE72E0049@DM6PR11MB2684.namprd11.prod.outlook.com/

> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
> ---
>   drivers/iommu/amd/iommu.c   |  2 ++
>   drivers/iommu/intel/iommu.c | 16 +++++++++++-----
>   include/linux/iommu.h       |  5 +++++
>   3 files changed, 18 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
> index 45299eb7e8e306..240c535e317cc7 100644
> --- a/drivers/iommu/amd/iommu.c
> +++ b/drivers/iommu/amd/iommu.c
> @@ -2278,6 +2278,8 @@ static bool amd_iommu_capable(struct device *dev, enum iommu_cap cap)
>   		return false;
>   	case IOMMU_CAP_PRE_BOOT_PROTECTION:
>   		return amdr_ivrs_remap_support;
> +	case IOMMU_CAP_ENFORCE_CACHE_COHERENCY:
> +		return true;
>   	default:
>   		break;
>   	}
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index f298e51d5aa67a..157c9727411076 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -4450,14 +4450,20 @@ static bool intel_iommu_enforce_cache_coherency(struct iommu_domain *domain)
>   
>   static bool intel_iommu_capable(struct device *dev, enum iommu_cap cap)
>   {
> -	if (cap == IOMMU_CAP_CACHE_COHERENCY)
> +	struct device_domain_info *info = dev_iommu_priv_get(dev);
> +
> +	switch (cap) {
> +	case IOMMU_CAP_CACHE_COHERENCY:
>   		return true;
> -	if (cap == IOMMU_CAP_INTR_REMAP)
> +	case IOMMU_CAP_INTR_REMAP:
>   		return irq_remapping_enabled == 1;
> -	if (cap == IOMMU_CAP_PRE_BOOT_PROTECTION)
> +	case IOMMU_CAP_PRE_BOOT_PROTECTION:
>   		return dmar_platform_optin();
> -
> -	return false;
> +	case IOMMU_CAP_ENFORCE_CACHE_COHERENCY:
> +		return ecap_sc_support(info->iommu->ecap);
> +	default:
> +		return false;
> +	}
>   }
>   
>   static struct iommu_device *intel_iommu_probe_device(struct device *dev)
> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
> index 68d7d304cdb761..a09fd32d8cc273 100644
> --- a/include/linux/iommu.h
> +++ b/include/linux/iommu.h
> @@ -124,6 +124,11 @@ enum iommu_cap {
>   	IOMMU_CAP_NOEXEC,		/* IOMMU_NOEXEC flag */
>   	IOMMU_CAP_PRE_BOOT_PROTECTION,	/* Firmware says it used the IOMMU for
>   					   DMA protection and we should too */
> +	/*
> +	 * Per-device flag indicating if enforce_cache_coherency() will work on
> +	 * this device.
> +	 */
> +	IOMMU_CAP_ENFORCE_CACHE_COHERENCY,
>   };
>   
>   /* These are the possible reserved region types */
Jason Gunthorpe Nov. 23, 2022, 4:56 p.m. UTC | #2 
On Wed, Nov 23, 2022 at 04:30:23PM +0800, Yi Liu wrote:
> On 2022/11/17 05:00, Jason Gunthorpe wrote:
> > This queries if a domain linked to a device should expect to support
> > enforce_cache_coherency() so iommufd can negotiate the rules for when a
> > domain should be shared or not.
> > 
> > For iommufd a device that declares IOMMU_CAP_ENFORCE_CACHE_COHERENCY will
> > not be attached to a domain that does not support it.
> > 
> > Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
> > Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> > Tested-by: Nicolin Chen <nicolinc@nvidia.com>
> > Tested-by: Yi Liu <yi.l.liu@intel.com>
> > Tested-by: Lixiao Yang <lixiao.yang@intel.com>
> > Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
> 
> looks like Yu He's test-by was missed. :-) She has given it in below link.

Oops, I fixed it thanks

Jason
diff mbox series

Patch

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 45299eb7e8e306..240c535e317cc7 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2278,6 +2278,8 @@  static bool amd_iommu_capable(struct device *dev, enum iommu_cap cap)
 		return false;
 	case IOMMU_CAP_PRE_BOOT_PROTECTION:
 		return amdr_ivrs_remap_support;
+	case IOMMU_CAP_ENFORCE_CACHE_COHERENCY:
+		return true;
 	default:
 		break;
 	}
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index f298e51d5aa67a..157c9727411076 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4450,14 +4450,20 @@  static bool intel_iommu_enforce_cache_coherency(struct iommu_domain *domain)
 
 static bool intel_iommu_capable(struct device *dev, enum iommu_cap cap)
 {
-	if (cap == IOMMU_CAP_CACHE_COHERENCY)
+	struct device_domain_info *info = dev_iommu_priv_get(dev);
+
+	switch (cap) {
+	case IOMMU_CAP_CACHE_COHERENCY:
 		return true;
-	if (cap == IOMMU_CAP_INTR_REMAP)
+	case IOMMU_CAP_INTR_REMAP:
 		return irq_remapping_enabled == 1;
-	if (cap == IOMMU_CAP_PRE_BOOT_PROTECTION)
+	case IOMMU_CAP_PRE_BOOT_PROTECTION:
 		return dmar_platform_optin();
-
-	return false;
+	case IOMMU_CAP_ENFORCE_CACHE_COHERENCY:
+		return ecap_sc_support(info->iommu->ecap);
+	default:
+		return false;
+	}
 }
 
 static struct iommu_device *intel_iommu_probe_device(struct device *dev)
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 68d7d304cdb761..a09fd32d8cc273 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -124,6 +124,11 @@  enum iommu_cap {
 	IOMMU_CAP_NOEXEC,		/* IOMMU_NOEXEC flag */
 	IOMMU_CAP_PRE_BOOT_PROTECTION,	/* Firmware says it used the IOMMU for
 					   DMA protection and we should too */
+	/*
+	 * Per-device flag indicating if enforce_cache_coherency() will work on
+	 * this device.
+	 */
+	IOMMU_CAP_ENFORCE_CACHE_COHERENCY,
 };
 
 /* These are the possible reserved region types */