diff mbox series

[v2,7/8] iommu/arm-smmu-v3: Implement IOMMU_HWPT_ALLOC_NEST_PARENT

Message ID 7-v2-621370057090+91fec-smmuv3_nesting_jgg@nvidia.com (mailing list archive)
State New, archived
Headers show
Series Initial support for SMMUv3 nested translation | expand

Commit Message

Jason Gunthorpe Aug. 27, 2024, 3:51 p.m. UTC
For SMMUv3 the parent must be a S2 domain, which can be composed
into a IOMMU_DOMAIN_NESTED.

In future the S2 parent will also need a VMID linked to the VIOMMU and
even to KVM.

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

Comments

Nicolin Chen Aug. 27, 2024, 8:16 p.m. UTC | #1
On Tue, Aug 27, 2024 at 12:51:37PM -0300, Jason Gunthorpe wrote:
> For SMMUv3 the parent must be a S2 domain, which can be composed
> into a IOMMU_DOMAIN_NESTED.
> 
> In future the S2 parent will also need a VMID linked to the VIOMMU and
> even to KVM.
> 
> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Tian, Kevin Aug. 30, 2024, 7:58 a.m. UTC | #2
> From: Jason Gunthorpe <jgg@nvidia.com>
> Sent: Tuesday, August 27, 2024 11:52 PM
> 
> For SMMUv3 the parent must be a S2 domain, which can be composed
> into a IOMMU_DOMAIN_NESTED.
> 
> In future the S2 parent will also need a VMID linked to the VIOMMU and
> even to KVM.
> 
> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Reviewed-by: Kevin Tian <kevin.tian@intel.com>, with a nit:

> @@ -3103,7 +3103,8 @@ arm_smmu_domain_alloc_user(struct device *dev,
> u32 flags,
>  			   const struct iommu_user_data *user_data)
>  {
>  	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
> -	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING;
> +	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING |
> +				 IOMMU_HWPT_ALLOC_NEST_PARENT;

lowercase for variable name.
Jason Gunthorpe Aug. 30, 2024, 1:55 p.m. UTC | #3
On Fri, Aug 30, 2024 at 07:58:09AM +0000, Tian, Kevin wrote:
> > @@ -3103,7 +3103,8 @@ arm_smmu_domain_alloc_user(struct device *dev,
> > u32 flags,
> >  			   const struct iommu_user_data *user_data)
> >  {
> >  	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
> > -	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING;
> > +	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING |
> > +				 IOMMU_HWPT_ALLOC_NEST_PARENT;
> 
> lowercase for variable name.

Ah, but it is constant :) I have no idea if there is a style consensus
here

Thanks,
Jason
Mostafa Saleh Aug. 30, 2024, 3:27 p.m. UTC | #4
Hi Jason,

On Tue, Aug 27, 2024 at 12:51:37PM -0300, Jason Gunthorpe wrote:
> For SMMUv3 the parent must be a S2 domain, which can be composed
> into a IOMMU_DOMAIN_NESTED.
> 
> In future the S2 parent will also need a VMID linked to the VIOMMU and
> even to KVM.
> 
> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
> ---
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 11 ++++++++++-
>  1 file changed, 10 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> index ec2fcdd4523a26..8db3db6328f8b7 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -3103,7 +3103,8 @@ arm_smmu_domain_alloc_user(struct device *dev, u32 flags,
>  			   const struct iommu_user_data *user_data)
>  {
>  	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
> -	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING;
> +	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING |
> +				 IOMMU_HWPT_ALLOC_NEST_PARENT;
>  	struct arm_smmu_domain *smmu_domain;
>  	int ret;
>  
> @@ -3116,6 +3117,14 @@ arm_smmu_domain_alloc_user(struct device *dev, u32 flags,
>  	if (!smmu_domain)
>  		return ERR_PTR(-ENOMEM);
>  
> +	if (flags & IOMMU_HWPT_ALLOC_NEST_PARENT) {
> +		if (!(master->smmu->features & ARM_SMMU_FEAT_NESTING)) {
> +			ret = -EOPNOTSUPP;
I think that should be:
	ret = ERR_PTR(-EOPNOTSUPP);

Thanks,
Mostafa
> +			goto err_free;
> +		}
> +		smmu_domain->stage = ARM_SMMU_DOMAIN_S2;
> +	}
> +
>  	smmu_domain->domain.type = IOMMU_DOMAIN_UNMANAGED;
>  	smmu_domain->domain.ops = arm_smmu_ops.default_domain_ops;
>  	ret = arm_smmu_domain_finalise(smmu_domain, master->smmu, flags);
> -- 
> 2.46.0
>
Jason Gunthorpe Aug. 30, 2024, 5:18 p.m. UTC | #5
On Fri, Aug 30, 2024 at 03:27:00PM +0000, Mostafa Saleh wrote:
> Hi Jason,
> 
> On Tue, Aug 27, 2024 at 12:51:37PM -0300, Jason Gunthorpe wrote:
> > For SMMUv3 the parent must be a S2 domain, which can be composed
> > into a IOMMU_DOMAIN_NESTED.
> > 
> > In future the S2 parent will also need a VMID linked to the VIOMMU and
> > even to KVM.
> > 
> > Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
> > ---
> >  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 11 ++++++++++-
> >  1 file changed, 10 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> > index ec2fcdd4523a26..8db3db6328f8b7 100644
> > --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> > +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> > @@ -3103,7 +3103,8 @@ arm_smmu_domain_alloc_user(struct device *dev, u32 flags,
> >  			   const struct iommu_user_data *user_data)
> >  {
> >  	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
> > -	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING;
> > +	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING |
> > +				 IOMMU_HWPT_ALLOC_NEST_PARENT;
> >  	struct arm_smmu_domain *smmu_domain;
> >  	int ret;
> >  
> > @@ -3116,6 +3117,14 @@ arm_smmu_domain_alloc_user(struct device *dev, u32 flags,
> >  	if (!smmu_domain)
> >  		return ERR_PTR(-ENOMEM);
> >  
> > +	if (flags & IOMMU_HWPT_ALLOC_NEST_PARENT) {
> > +		if (!(master->smmu->features & ARM_SMMU_FEAT_NESTING)) {
> > +			ret = -EOPNOTSUPP;
> I think that should be:
> 	ret = ERR_PTR(-EOPNOTSUPP);

Read again :)

static struct iommu_domain *
arm_smmu_domain_alloc_user(struct device *dev, u32 flags,
			   struct iommu_domain *parent,
			   const struct iommu_user_data *user_data)
{
	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING |
				 IOMMU_HWPT_ALLOC_NEST_PARENT;
	struct arm_smmu_domain *smmu_domain;
	int ret;
     ^^^^^^^^^^^^^^

err_free:
	kfree(smmu_domain);
	return ERR_PTR(ret);
           ^^^^^^^^^^^^^^^^^^

Jason
Mostafa Saleh Sept. 2, 2024, 8:57 a.m. UTC | #6
On Fri, Aug 30, 2024 at 02:18:17PM -0300, Jason Gunthorpe wrote:
> On Fri, Aug 30, 2024 at 03:27:00PM +0000, Mostafa Saleh wrote:
> > Hi Jason,
> > 
> > On Tue, Aug 27, 2024 at 12:51:37PM -0300, Jason Gunthorpe wrote:
> > > For SMMUv3 the parent must be a S2 domain, which can be composed
> > > into a IOMMU_DOMAIN_NESTED.
> > > 
> > > In future the S2 parent will also need a VMID linked to the VIOMMU and
> > > even to KVM.
> > > 
> > > Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
> > > ---
> > >  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 11 ++++++++++-
> > >  1 file changed, 10 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> > > index ec2fcdd4523a26..8db3db6328f8b7 100644
> > > --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> > > +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> > > @@ -3103,7 +3103,8 @@ arm_smmu_domain_alloc_user(struct device *dev, u32 flags,
> > >  			   const struct iommu_user_data *user_data)
> > >  {
> > >  	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
> > > -	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING;
> > > +	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING |
> > > +				 IOMMU_HWPT_ALLOC_NEST_PARENT;
> > >  	struct arm_smmu_domain *smmu_domain;
> > >  	int ret;
> > >  
> > > @@ -3116,6 +3117,14 @@ arm_smmu_domain_alloc_user(struct device *dev, u32 flags,
> > >  	if (!smmu_domain)
> > >  		return ERR_PTR(-ENOMEM);
> > >  
> > > +	if (flags & IOMMU_HWPT_ALLOC_NEST_PARENT) {
> > > +		if (!(master->smmu->features & ARM_SMMU_FEAT_NESTING)) {
> > > +			ret = -EOPNOTSUPP;
> > I think that should be:
> > 	ret = ERR_PTR(-EOPNOTSUPP);
> 
> Read again :)

Oops, sorry about the noise.

Thanks,
Mostafa
> 
> static struct iommu_domain *
> arm_smmu_domain_alloc_user(struct device *dev, u32 flags,
> 			   struct iommu_domain *parent,
> 			   const struct iommu_user_data *user_data)
> {
> 	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
> 	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING |
> 				 IOMMU_HWPT_ALLOC_NEST_PARENT;
> 	struct arm_smmu_domain *smmu_domain;
> 	int ret;
>      ^^^^^^^^^^^^^^
> 
> err_free:
> 	kfree(smmu_domain);
> 	return ERR_PTR(ret);
>            ^^^^^^^^^^^^^^^^^^
> 
> Jason
diff mbox series

Patch

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index ec2fcdd4523a26..8db3db6328f8b7 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -3103,7 +3103,8 @@  arm_smmu_domain_alloc_user(struct device *dev, u32 flags,
 			   const struct iommu_user_data *user_data)
 {
 	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
-	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING;
+	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING |
+				 IOMMU_HWPT_ALLOC_NEST_PARENT;
 	struct arm_smmu_domain *smmu_domain;
 	int ret;
 
@@ -3116,6 +3117,14 @@  arm_smmu_domain_alloc_user(struct device *dev, u32 flags,
 	if (!smmu_domain)
 		return ERR_PTR(-ENOMEM);
 
+	if (flags & IOMMU_HWPT_ALLOC_NEST_PARENT) {
+		if (!(master->smmu->features & ARM_SMMU_FEAT_NESTING)) {
+			ret = -EOPNOTSUPP;
+			goto err_free;
+		}
+		smmu_domain->stage = ARM_SMMU_DOMAIN_S2;
+	}
+
 	smmu_domain->domain.type = IOMMU_DOMAIN_UNMANAGED;
 	smmu_domain->domain.ops = arm_smmu_ops.default_domain_ops;
 	ret = arm_smmu_domain_finalise(smmu_domain, master->smmu, flags);