Re: [PATCH v3 02/14] iommu: Report domain nesting info
On Tue, Jun 30, 2020 at 02:00:49AM +, Tian, Kevin wrote: > > From: Liu, Yi L > > Sent: Monday, June 29, 2020 8:23 PM > > > > Hi Stefan, > > > > > From: Stefan Hajnoczi > > > Sent: Monday, June 29, 2020 5:25 PM > > > > > > On Wed, Jun 24, 2020 at 01:55:15AM -0700, Liu Yi L wrote: > > > > +/* > > > > + * struct iommu_nesting_info - Information for nesting-capable IOMMU. > > > > + * user space should check it before using > > > > + * nesting capability. > > > > + * > > > > + * @size: size of the whole structure > > > > + * @format:PASID table entry format, the same definition with > > > > + * @format of struct iommu_gpasid_bind_data. > > > > + * @features: supported nesting features. > > > > + * @flags: currently reserved for future extension. > > > > + * @data: vendor specific cap info. > > > > + * > > > > + * > > > > +---++ > > > > + * | feature | Notes > > > > | > > > > + * > > > > > +===+=== > > > > > =+ > > > > + * | SYSWIDE_PASID | Kernel manages PASID in system wide, PASIDs > > used | > > > > + * | | in the system should be allocated by host kernel > > > > | > > > > + * > > > > +---++ > > > > + * | BIND_PGTBL| bind page tables to host PASID, the PASID could > > > > | > > > > + * | | either be a host PASID passed in bind request or > > > > | > > > > + * | | default PASIDs (e.g. default PASID of > > > > aux-domain) | > > > > + * > > > > +---++ > > > > + * | CACHE_INVLD | mandatory feature for nesting capable IOMMU > > | > > > > + * > > > > +---++ > > > > > > This feature description is vague about what CACHE_INVLD does and how > > to > > > use it. If I understand correctly, the presence of this feature means > > > that VFIO_IOMMU_NESTING_OP_CACHE_INVLD must be used? > > > > > > The same kind of clarification could be done for SYSWIDE_PASID and > > > BIND_PGTBL too. > > > > For SYSWIDE_PASID and BIND_PGTBL, yes, presence of the feature bit > > means must use. So the two are requirements to user space if it wants > > to setup nesting. While for CACHE_INVLD, it's kind of availability > > here. How about removing CACHE_INVLD as presence of BIND_PGTBL should > > indicates support of CACHE_INVLD? > > > > So far this assumption is correct but it may not be true when thinking > forward. > For example, a vendor might find a way to allow the owner of 1st-level page > table to directly invalidate cache w/o going through host IOMMU driver. From > this angle I feel explicitly reporting this capability is more robust. > > Regarding to the description, what about below? > > -- > SYSWIDE_PASID: PASIDs are managed in system-wide, instead of per device. > When a device is assigned to userspace or VM, proper uAPI (provided by > userspace driver framework, e.g. VFIO) must be used to allocate/free PASIDs > for the assigned device. > > BIND_PGTBL: The owner of the first-level/stage-1 page table must explicitly > bind the page table to associated PASID (either the one specified in bind > request or the default PASID of the iommu domain), through VFIO_IOMMU > _NESTING_OP > > CACHE_INVLD: The owner of the first-level/stage-1 page table must > explicitly invalidate the IOMMU cache through VFIO_IOMMU_NESTING_OP, > according to vendor-specific requirement when changing the page table. > -- Mentioning the API to allocate/free PASIDs and VFIO_IOMMU_NESTING_OP has made this clearer. This lets someone reading the documentation know where to look for further information on using these features. Thank you! Stefan signature.asc Description: PGP signature ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
RE: [PATCH v3 02/14] iommu: Report domain nesting info
> From: Alex Williamson
> Sent: Friday, July 3, 2020 1:55 AM
>
> On Wed, 24 Jun 2020 01:55:15 -0700
> Liu Yi L wrote:
>
> > IOMMUs that support nesting translation needs report the capability
> > info to userspace, e.g. the format of first level/stage paging structures.
> >
> > This patch reports nesting info by DOMAIN_ATTR_NESTING. Caller can get
> > nesting info after setting DOMAIN_ATTR_NESTING.
> >
> > v2 -> v3:
> > *) remvoe cap/ecap_mask in iommu_nesting_info.
> > *) reuse DOMAIN_ATTR_NESTING to get nesting info.
> > *) return an empty iommu_nesting_info for SMMU drivers per Jean'
> >suggestion.
> >
> > 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
> > ---
> > drivers/iommu/arm-smmu-v3.c | 29 --
> > drivers/iommu/arm-smmu.c| 29 --
> > include/uapi/linux/iommu.h | 59
> > +
> > 3 files changed, 113 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
> > index f578677..0c45d4d 100644
> > --- a/drivers/iommu/arm-smmu-v3.c
> > +++ b/drivers/iommu/arm-smmu-v3.c
> > @@ -3019,6 +3019,32 @@ static struct iommu_group
> *arm_smmu_device_group(struct device *dev)
> > return group;
> > }
> >
> > +static int arm_smmu_domain_nesting_info(struct arm_smmu_domain
> *smmu_domain,
> > + void *data)
> > +{
> > + struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
> > + u32 size;
> > +
> > + if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
> > + return -ENODEV;
> > +
> > + size = sizeof(struct iommu_nesting_info);
> > +
> > + /*
> > +* if provided buffer size is not equal to the size, should
> > +* return 0 and also the expected buffer size to caller.
> > +*/
> > + if (info->size != size) {
> > + info->size = size;
> > + return 0;
> > + }
> > +
> > + /* report an empty iommu_nesting_info for now */
> > + memset(info, 0x0, size);
> > + info->size = size;
> > + return 0;
> > +}
> > +
> > static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> > enum iommu_attr attr, void *data) { @@ -
> 3028,8 +3054,7 @@
> > static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> > case IOMMU_DOMAIN_UNMANAGED:
> > switch (attr) {
> > case DOMAIN_ATTR_NESTING:
> > - *(int *)data = (smmu_domain->stage ==
> ARM_SMMU_DOMAIN_NESTED);
> > - return 0;
> > + return arm_smmu_domain_nesting_info(smmu_domain,
> data);
> > default:
> > return -ENODEV;
> > }
> > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index
> > 243bc4c..908607d 100644
> > --- a/drivers/iommu/arm-smmu.c
> > +++ b/drivers/iommu/arm-smmu.c
> > @@ -1506,6 +1506,32 @@ static struct iommu_group
> *arm_smmu_device_group(struct device *dev)
> > return group;
> > }
> >
> > +static int arm_smmu_domain_nesting_info(struct arm_smmu_domain
> *smmu_domain,
> > + void *data)
> > +{
> > + struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
> > + u32 size;
> > +
> > + if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
> > + return -ENODEV;
> > +
> > + size = sizeof(struct iommu_nesting_info);
> > +
> > + /*
> > +* if provided buffer size is not equal to the size, should
> > +* return 0 and also the expected buffer size to caller.
> > +*/
> > + if (info->size != size) {
> > + info->size = size;
> > + return 0;
> > + }
> > +
> > + /* report an empty iommu_nesting_info for now */
> > + memset(info, 0x0, size);
> > + info->size = size;
> > + return 0;
> > +}
> > +
> > static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> > enum iommu_attr attr, void *data) { @@ -
> 1515,8 +1541,7 @@
> > static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> > case IOMMU_DOMAIN_UNMANAGED:
> > switch (attr) {
> > case DOMAIN_ATTR_NESTING:
> > - *(int *)data = (smmu_domain->stage ==
> ARM_SMMU_DOMAIN_NESTED);
> > - return 0;
> > + return arm_smmu_domain_nesting_info(smmu_domain,
> data);
> > default:
> > return -ENODEV;
> > }
> > diff --git a/include/uapi/linux/iommu.h b/include/uapi/linux/iommu.h
> > index 1afc661..898c99a 100644
> > --- a/include/uapi/linux/iommu.h
> > +++ b/include/uapi/linux/iommu.h
> > @@ -332,4 +332,63 @@ struct iommu_gpasid_bind_data {
> > } vendor;
> > };
> >
> > +/*
> > + * struct iommu_nesting_info - Information for nesting-capable IOMMU.
Re: [PATCH v3 02/14] iommu: Report domain nesting info
On Wed, 24 Jun 2020 01:55:15 -0700
Liu Yi L wrote:
> IOMMUs that support nesting translation needs report the capability info
> to userspace, e.g. the format of first level/stage paging structures.
>
> This patch reports nesting info by DOMAIN_ATTR_NESTING. Caller can get
> nesting info after setting DOMAIN_ATTR_NESTING.
>
> v2 -> v3:
> *) remvoe cap/ecap_mask in iommu_nesting_info.
> *) reuse DOMAIN_ATTR_NESTING to get nesting info.
> *) return an empty iommu_nesting_info for SMMU drivers per Jean'
>suggestion.
>
> 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
> ---
> drivers/iommu/arm-smmu-v3.c | 29 --
> drivers/iommu/arm-smmu.c| 29 --
> include/uapi/linux/iommu.h | 59
> +
> 3 files changed, 113 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
> index f578677..0c45d4d 100644
> --- a/drivers/iommu/arm-smmu-v3.c
> +++ b/drivers/iommu/arm-smmu-v3.c
> @@ -3019,6 +3019,32 @@ static struct iommu_group
> *arm_smmu_device_group(struct device *dev)
> return group;
> }
>
> +static int arm_smmu_domain_nesting_info(struct arm_smmu_domain *smmu_domain,
> + void *data)
> +{
> + struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
> + u32 size;
> +
> + if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
> + return -ENODEV;
> +
> + size = sizeof(struct iommu_nesting_info);
> +
> + /*
> + * if provided buffer size is not equal to the size, should
> + * return 0 and also the expected buffer size to caller.
> + */
> + if (info->size != size) {
> + info->size = size;
> + return 0;
> + }
> +
> + /* report an empty iommu_nesting_info for now */
> + memset(info, 0x0, size);
> + info->size = size;
> + return 0;
> +}
> +
> static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> enum iommu_attr attr, void *data)
> {
> @@ -3028,8 +3054,7 @@ static int arm_smmu_domain_get_attr(struct iommu_domain
> *domain,
> case IOMMU_DOMAIN_UNMANAGED:
> switch (attr) {
> case DOMAIN_ATTR_NESTING:
> - *(int *)data = (smmu_domain->stage ==
> ARM_SMMU_DOMAIN_NESTED);
> - return 0;
> + return arm_smmu_domain_nesting_info(smmu_domain, data);
> default:
> return -ENODEV;
> }
> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> index 243bc4c..908607d 100644
> --- a/drivers/iommu/arm-smmu.c
> +++ b/drivers/iommu/arm-smmu.c
> @@ -1506,6 +1506,32 @@ static struct iommu_group
> *arm_smmu_device_group(struct device *dev)
> return group;
> }
>
> +static int arm_smmu_domain_nesting_info(struct arm_smmu_domain *smmu_domain,
> + void *data)
> +{
> + struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
> + u32 size;
> +
> + if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
> + return -ENODEV;
> +
> + size = sizeof(struct iommu_nesting_info);
> +
> + /*
> + * if provided buffer size is not equal to the size, should
> + * return 0 and also the expected buffer size to caller.
> + */
> + if (info->size != size) {
> + info->size = size;
> + return 0;
> + }
> +
> + /* report an empty iommu_nesting_info for now */
> + memset(info, 0x0, size);
> + info->size = size;
> + return 0;
> +}
> +
> static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> enum iommu_attr attr, void *data)
> {
> @@ -1515,8 +1541,7 @@ static int arm_smmu_domain_get_attr(struct iommu_domain
> *domain,
> case IOMMU_DOMAIN_UNMANAGED:
> switch (attr) {
> case DOMAIN_ATTR_NESTING:
> - *(int *)data = (smmu_domain->stage ==
> ARM_SMMU_DOMAIN_NESTED);
> - return 0;
> + return arm_smmu_domain_nesting_info(smmu_domain, data);
> default:
> return -ENODEV;
> }
> diff --git a/include/uapi/linux/iommu.h b/include/uapi/linux/iommu.h
> index 1afc661..898c99a 100644
> --- a/include/uapi/linux/iommu.h
> +++ b/include/uapi/linux/iommu.h
> @@ -332,4 +332,63 @@ struct iommu_gpasid_bind_data {
> } vendor;
> };
>
> +/*
> + * struct iommu_nesting_info - Information for nesting-capable IOMMU.
> + * user space should check it before using
> + * nesting capability.
> + *
> + * @size:size of the whole structure
> + * @format: PASID table
RE: [PATCH v3 02/14] iommu: Report domain nesting info
> From: Tian, Kevin > Sent: Tuesday, June 30, 2020 10:01 AM > > > From: Liu, Yi L > > Sent: Monday, June 29, 2020 8:23 PM > > > > Hi Stefan, > > > > > From: Stefan Hajnoczi > > > Sent: Monday, June 29, 2020 5:25 PM > > > > > > On Wed, Jun 24, 2020 at 01:55:15AM -0700, Liu Yi L wrote: > > > > +/* > > > > + * struct iommu_nesting_info - Information for nesting-capable IOMMU. > > > > + * user space should check it before using > > > > + * nesting capability. > > > > + * > > > > + * @size: size of the whole structure > > > > + * @format:PASID table entry format, the same definition with > > > > + * @format of struct iommu_gpasid_bind_data. > > > > + * @features: supported nesting features. > > > > + * @flags: currently reserved for future extension. > > > > + * @data: vendor specific cap info. > > > > + * > > > > + * > > > > +---++ > > > > + * | feature | Notes > > > > | > > > > + * > > > > > +===+=== > > > > > =+ > > > > + * | SYSWIDE_PASID | Kernel manages PASID in system wide, PASIDs > > used | > > > > + * | | in the system should be allocated by host kernel > > > > | > > > > + * > > > > +---++ > > > > + * | BIND_PGTBL| bind page tables to host PASID, the PASID could > > > > | > > > > + * | | either be a host PASID passed in bind request or > > > > | > > > > + * | | default PASIDs (e.g. default PASID of > > > > aux-domain) | > > > > + * > > > > +---++ > > > > + * | CACHE_INVLD | mandatory feature for nesting capable IOMMU > > | > > > > + * > > > > +---++ > > > > > > This feature description is vague about what CACHE_INVLD does and how > > to > > > use it. If I understand correctly, the presence of this feature means > > > that VFIO_IOMMU_NESTING_OP_CACHE_INVLD must be used? > > > > > > The same kind of clarification could be done for SYSWIDE_PASID and > > > BIND_PGTBL too. > > > > For SYSWIDE_PASID and BIND_PGTBL, yes, presence of the feature bit > > means must use. So the two are requirements to user space if it wants > > to setup nesting. While for CACHE_INVLD, it's kind of availability > > here. How about removing CACHE_INVLD as presence of BIND_PGTBL should > > indicates support of CACHE_INVLD? > > > > So far this assumption is correct but it may not be true when thinking > forward. > For example, a vendor might find a way to allow the owner of 1st-level page > table to directly invalidate cache w/o going through host IOMMU driver. From > this angle I feel explicitly reporting this capability is more robust. I see. explicitly require 1st-level page table owner to do cache invalidation after modifying page table is fair to me. > Regarding to the description, what about below? > > -- > SYSWIDE_PASID: PASIDs are managed in system-wide, instead of per device. > When a device is assigned to userspace or VM, proper uAPI (provided by > userspace driver framework, e.g. VFIO) must be used to allocate/free PASIDs > for the assigned device. > > BIND_PGTBL: The owner of the first-level/stage-1 page table must explicitly > bind the page table to associated PASID (either the one specified in bind > request or the default PASID of the iommu domain), through VFIO_IOMMU > _NESTING_OP > > CACHE_INVLD: The owner of the first-level/stage-1 page table must > explicitly invalidate the IOMMU cache through VFIO_IOMMU_NESTING_OP, > according to vendor-specific requirement when changing the page table. > -- thanks for the statements, will apply. Regards, Yi Liu > Thanks > Kevin > > ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
RE: [PATCH v3 02/14] iommu: Report domain nesting info
> From: Liu, Yi L > Sent: Monday, June 29, 2020 8:23 PM > > Hi Stefan, > > > From: Stefan Hajnoczi > > Sent: Monday, June 29, 2020 5:25 PM > > > > On Wed, Jun 24, 2020 at 01:55:15AM -0700, Liu Yi L wrote: > > > +/* > > > + * struct iommu_nesting_info - Information for nesting-capable IOMMU. > > > + * user space should check it before using > > > + * nesting capability. > > > + * > > > + * @size:size of the whole structure > > > + * @format: PASID table entry format, the same definition with > > > + * @format of struct iommu_gpasid_bind_data. > > > + * @features:supported nesting features. > > > + * @flags: currently reserved for future extension. > > > + * @data:vendor specific cap info. > > > + * > > > + * +---++ > > > + * | feature | Notes | > > > + * > > > +===+=== > > > =+ > > > + * | SYSWIDE_PASID | Kernel manages PASID in system wide, PASIDs > used | > > > + * | | in the system should be allocated by host kernel | > > > + * +---++ > > > + * | BIND_PGTBL| bind page tables to host PASID, the PASID could | > > > + * | | either be a host PASID passed in bind request or | > > > + * | | default PASIDs (e.g. default PASID of aux-domain) | > > > + * +---++ > > > + * | CACHE_INVLD | mandatory feature for nesting capable IOMMU > | > > > + * +---++ > > > > This feature description is vague about what CACHE_INVLD does and how > to > > use it. If I understand correctly, the presence of this feature means > > that VFIO_IOMMU_NESTING_OP_CACHE_INVLD must be used? > > > > The same kind of clarification could be done for SYSWIDE_PASID and > > BIND_PGTBL too. > > For SYSWIDE_PASID and BIND_PGTBL, yes, presence of the feature bit > means must use. So the two are requirements to user space if it wants > to setup nesting. While for CACHE_INVLD, it's kind of availability > here. How about removing CACHE_INVLD as presence of BIND_PGTBL should > indicates support of CACHE_INVLD? > So far this assumption is correct but it may not be true when thinking forward. For example, a vendor might find a way to allow the owner of 1st-level page table to directly invalidate cache w/o going through host IOMMU driver. From this angle I feel explicitly reporting this capability is more robust. Regarding to the description, what about below? -- SYSWIDE_PASID: PASIDs are managed in system-wide, instead of per device. When a device is assigned to userspace or VM, proper uAPI (provided by userspace driver framework, e.g. VFIO) must be used to allocate/free PASIDs for the assigned device. BIND_PGTBL: The owner of the first-level/stage-1 page table must explicitly bind the page table to associated PASID (either the one specified in bind request or the default PASID of the iommu domain), through VFIO_IOMMU _NESTING_OP CACHE_INVLD: The owner of the first-level/stage-1 page table must explicitly invalidate the IOMMU cache through VFIO_IOMMU_NESTING_OP, according to vendor-specific requirement when changing the page table. -- Thanks Kevin ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
RE: [PATCH v3 02/14] iommu: Report domain nesting info
> From: Liu, Yi L
> Sent: Saturday, June 27, 2020 2:53 PM
>
> Hi Robin,
>
> > From: Robin Murphy
> > Sent: Saturday, June 27, 2020 12:05 AM
> >
> > On 2020-06-26 08:47, Jean-Philippe Brucker wrote:
> > > On Wed, Jun 24, 2020 at 01:55:15AM -0700, Liu Yi L wrote:
> > >> IOMMUs that support nesting translation needs report the capability
> > >> info to userspace, e.g. the format of first level/stage paging
> > >> structures.
> > >>
> > >> This patch reports nesting info by DOMAIN_ATTR_NESTING. Caller can
> > >> get nesting info after setting DOMAIN_ATTR_NESTING.
> > >>
> > >> v2 -> v3:
> > >> *) remvoe cap/ecap_mask in iommu_nesting_info.
> > >> *) reuse DOMAIN_ATTR_NESTING to get nesting info.
> > >> *) return an empty iommu_nesting_info for SMMU drivers per Jean'
> > >> suggestion.
> > >>
> > >> 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
> > >> ---
> > >> drivers/iommu/arm-smmu-v3.c | 29 --
> > >> drivers/iommu/arm-smmu.c| 29 --
> > >
> > > Looks reasonable to me. Please move the SMMU changes to a separate
> > > patch and Cc the SMMU maintainers:
> >
> > Cheers Jean, I'll admit I've been skipping over a lot of these patches
> > lately :)
> >
> > A couple of comments below...
> >
> > >
> > > Cc: Will Deacon
> > > Cc: Robin Murphy
> > >
> > > Thanks,
> > > Jean
> > >
> > >> include/uapi/linux/iommu.h | 59
> > +
> > >> 3 files changed, 113 insertions(+), 4 deletions(-)
> > >>
> > >> diff --git a/drivers/iommu/arm-smmu-v3.c
> > >> b/drivers/iommu/arm-smmu-v3.c index f578677..0c45d4d 100644
> > >> --- a/drivers/iommu/arm-smmu-v3.c
> > >> +++ b/drivers/iommu/arm-smmu-v3.c
> > >> @@ -3019,6 +3019,32 @@ static struct iommu_group
> > *arm_smmu_device_group(struct device *dev)
> > >> return group;
> > >> }
> > >>
> > >> +static int arm_smmu_domain_nesting_info(struct arm_smmu_domain
> > *smmu_domain,
> > >> +void *data)
> > >> +{
> > >> +struct iommu_nesting_info *info = (struct iommu_nesting_info *)
> data;
> > >> +u32 size;
> > >> +
> > >> +if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
> > >> +return -ENODEV;
> > >> +
> > >> +size = sizeof(struct iommu_nesting_info);
> > >> +
> > >> +/*
> > >> + * if provided buffer size is not equal to the size, should
> > >> + * return 0 and also the expected buffer size to caller.
> > >> + */
> > >> +if (info->size != size) {
> > >> +info->size = size;
> > >> +return 0;
> > >> +}
> > >> +
> > >> +/* report an empty iommu_nesting_info for now */
> > >> +memset(info, 0x0, size);
> > >> +info->size = size;
> > >> +return 0;
> > >> +}
> > >> +
> > >> static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> > >> enum iommu_attr attr, void *data)
> > >> {
> > >> @@ -3028,8 +3054,7 @@ static int arm_smmu_domain_get_attr(struct
> > iommu_domain *domain,
> > >> case IOMMU_DOMAIN_UNMANAGED:
> > >> switch (attr) {
> > >> case DOMAIN_ATTR_NESTING:
> > >> -*(int *)data = (smmu_domain->stage ==
> > ARM_SMMU_DOMAIN_NESTED);
> > >> -return 0;
> > >> +return
> arm_smmu_domain_nesting_info(smmu_domain,
> > data);
> > >> default:
> > >> return -ENODEV;
> > >> }
> > >> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> > >> index 243bc4c..908607d 100644
> > >> --- a/drivers/iommu/arm-smmu.c
> > >> +++ b/drivers/iommu/arm-smmu.c
> > >> @@ -1506,6 +1506,32 @@ static struct iommu_group
> > *arm_smmu_device_group(struct device *dev)
> > >> return group;
> > >> }
> > >>
> > >> +static int arm_smmu_domain_nesting_info(struct arm_smmu_domain
> > *smmu_domain,
> > >> +void *data)
> > >> +{
> > >> +struct iommu_nesting_info *info = (struct iommu_nesting_info *)
> data;
> > >> +u32 size;
> > >> +
> > >> +if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
> > >> +return -ENODEV;
> > >> +
> > >> +size = sizeof(struct iommu_nesting_info);
> > >> +
> > >> +/*
> > >> + * if provided buffer size is not equal to the size, should
> > >> + * return 0 and also the expected buffer size to caller.
> > >> + */
> > >> +if (info->size != size) {
> > >> +info->size = size;
> > >> +return 0;
> > >> +}
> > >> +
> > >> +/* report an empty iommu_nesting_info for now */
> > >> +
RE: [PATCH v3 02/14] iommu: Report domain nesting info
Hi Stefan, > From: Stefan Hajnoczi > Sent: Monday, June 29, 2020 5:25 PM > > On Wed, Jun 24, 2020 at 01:55:15AM -0700, Liu Yi L wrote: > > +/* > > + * struct iommu_nesting_info - Information for nesting-capable IOMMU. > > + * user space should check it before using > > + * nesting capability. > > + * > > + * @size: size of the whole structure > > + * @format:PASID table entry format, the same definition with > > + * @format of struct iommu_gpasid_bind_data. > > + * @features: supported nesting features. > > + * @flags: currently reserved for future extension. > > + * @data: vendor specific cap info. > > + * > > + * +---++ > > + * | feature | Notes | > > + * > +===+=== > =+ > > + * | SYSWIDE_PASID | Kernel manages PASID in system wide, PASIDs used | > > + * | | in the system should be allocated by host kernel | > > + * +---++ > > + * | BIND_PGTBL| bind page tables to host PASID, the PASID could | > > + * | | either be a host PASID passed in bind request or | > > + * | | default PASIDs (e.g. default PASID of aux-domain) | > > + * +---++ > > + * | CACHE_INVLD | mandatory feature for nesting capable IOMMU | > > + * +---++ > > This feature description is vague about what CACHE_INVLD does and how to > use it. If I understand correctly, the presence of this feature means > that VFIO_IOMMU_NESTING_OP_CACHE_INVLD must be used? > > The same kind of clarification could be done for SYSWIDE_PASID and > BIND_PGTBL too. For SYSWIDE_PASID and BIND_PGTBL, yes, presence of the feature bit means must use. So the two are requirements to user space if it wants to setup nesting. While for CACHE_INVLD, it's kind of availability here. How about removing CACHE_INVLD as presence of BIND_PGTBL should indicates support of CACHE_INVLD? Regards, Yi Liu > Stefan ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
Re: [PATCH v3 02/14] iommu: Report domain nesting info
On Wed, Jun 24, 2020 at 01:55:15AM -0700, Liu Yi L wrote: > +/* > + * struct iommu_nesting_info - Information for nesting-capable IOMMU. > + * user space should check it before using > + * nesting capability. > + * > + * @size:size of the whole structure > + * @format: PASID table entry format, the same definition with > + * @format of struct iommu_gpasid_bind_data. > + * @features:supported nesting features. > + * @flags: currently reserved for future extension. > + * @data:vendor specific cap info. > + * > + * +---++ > + * | feature | Notes | > + * +===++ > + * | SYSWIDE_PASID | Kernel manages PASID in system wide, PASIDs used | > + * | | in the system should be allocated by host kernel | > + * +---++ > + * | BIND_PGTBL| bind page tables to host PASID, the PASID could | > + * | | either be a host PASID passed in bind request or | > + * | | default PASIDs (e.g. default PASID of aux-domain) | > + * +---++ > + * | CACHE_INVLD | mandatory feature for nesting capable IOMMU | > + * +---++ This feature description is vague about what CACHE_INVLD does and how to use it. If I understand correctly, the presence of this feature means that VFIO_IOMMU_NESTING_OP_CACHE_INVLD must be used? The same kind of clarification could be done for SYSWIDE_PASID and BIND_PGTBL too. Stefan signature.asc Description: PGP signature ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
RE: [PATCH v3 02/14] iommu: Report domain nesting info
Hi Robin,
> From: Robin Murphy
> Sent: Saturday, June 27, 2020 12:05 AM
>
> On 2020-06-26 08:47, Jean-Philippe Brucker wrote:
> > On Wed, Jun 24, 2020 at 01:55:15AM -0700, Liu Yi L wrote:
> >> IOMMUs that support nesting translation needs report the capability
> >> info to userspace, e.g. the format of first level/stage paging structures.
> >>
> >> This patch reports nesting info by DOMAIN_ATTR_NESTING. Caller can
> >> get nesting info after setting DOMAIN_ATTR_NESTING.
> >>
> >> v2 -> v3:
> >> *) remvoe cap/ecap_mask in iommu_nesting_info.
> >> *) reuse DOMAIN_ATTR_NESTING to get nesting info.
> >> *) return an empty iommu_nesting_info for SMMU drivers per Jean'
> >> suggestion.
> >>
> >> 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
> >> ---
> >> drivers/iommu/arm-smmu-v3.c | 29 --
> >> drivers/iommu/arm-smmu.c| 29 --
> >
> > Looks reasonable to me. Please move the SMMU changes to a separate
> > patch and Cc the SMMU maintainers:
>
> Cheers Jean, I'll admit I've been skipping over a lot of these patches lately
> :)
>
> A couple of comments below...
>
> >
> > Cc: Will Deacon
> > Cc: Robin Murphy
> >
> > Thanks,
> > Jean
> >
> >> include/uapi/linux/iommu.h | 59
> +
> >> 3 files changed, 113 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/drivers/iommu/arm-smmu-v3.c
> >> b/drivers/iommu/arm-smmu-v3.c index f578677..0c45d4d 100644
> >> --- a/drivers/iommu/arm-smmu-v3.c
> >> +++ b/drivers/iommu/arm-smmu-v3.c
> >> @@ -3019,6 +3019,32 @@ static struct iommu_group
> *arm_smmu_device_group(struct device *dev)
> >>return group;
> >> }
> >>
> >> +static int arm_smmu_domain_nesting_info(struct arm_smmu_domain
> *smmu_domain,
> >> + void *data)
> >> +{
> >> + struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
> >> + u32 size;
> >> +
> >> + if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
> >> + return -ENODEV;
> >> +
> >> + size = sizeof(struct iommu_nesting_info);
> >> +
> >> + /*
> >> + * if provided buffer size is not equal to the size, should
> >> + * return 0 and also the expected buffer size to caller.
> >> + */
> >> + if (info->size != size) {
> >> + info->size = size;
> >> + return 0;
> >> + }
> >> +
> >> + /* report an empty iommu_nesting_info for now */
> >> + memset(info, 0x0, size);
> >> + info->size = size;
> >> + return 0;
> >> +}
> >> +
> >> static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> >>enum iommu_attr attr, void *data)
> >> {
> >> @@ -3028,8 +3054,7 @@ static int arm_smmu_domain_get_attr(struct
> iommu_domain *domain,
> >>case IOMMU_DOMAIN_UNMANAGED:
> >>switch (attr) {
> >>case DOMAIN_ATTR_NESTING:
> >> - *(int *)data = (smmu_domain->stage ==
> ARM_SMMU_DOMAIN_NESTED);
> >> - return 0;
> >> + return arm_smmu_domain_nesting_info(smmu_domain,
> data);
> >>default:
> >>return -ENODEV;
> >>}
> >> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> >> index 243bc4c..908607d 100644
> >> --- a/drivers/iommu/arm-smmu.c
> >> +++ b/drivers/iommu/arm-smmu.c
> >> @@ -1506,6 +1506,32 @@ static struct iommu_group
> *arm_smmu_device_group(struct device *dev)
> >>return group;
> >> }
> >>
> >> +static int arm_smmu_domain_nesting_info(struct arm_smmu_domain
> *smmu_domain,
> >> + void *data)
> >> +{
> >> + struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
> >> + u32 size;
> >> +
> >> + if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
> >> + return -ENODEV;
> >> +
> >> + size = sizeof(struct iommu_nesting_info);
> >> +
> >> + /*
> >> + * if provided buffer size is not equal to the size, should
> >> + * return 0 and also the expected buffer size to caller.
> >> + */
> >> + if (info->size != size) {
> >> + info->size = size;
> >> + return 0;
> >> + }
> >> +
> >> + /* report an empty iommu_nesting_info for now */
> >> + memset(info, 0x0, size);
> >> + info->size = size;
> >> + return 0;
> >> +}
> >> +
> >> static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> >>enum iommu_attr attr, void *data)
> >> {
> >> @@ -1515,8 +1541,7 @@ static int arm_smmu_domain_get_attr(struct
> iommu_domain *domain,
> >>case IOMMU_DOMAIN_UNMANAGED:
> >>switch (attr) {
> >>case DOMAIN_ATTR_NESTING:
> >> - *(int *)data = (smmu_domain->stage ==
> ARM_SMMU_DOMAIN_NESTED);
> >> - return 0;
> >> + return
RE: [PATCH v3 02/14] iommu: Report domain nesting info
> From: Jean-Philippe Brucker
> Sent: Friday, June 26, 2020 3:48 PM
>
> On Wed, Jun 24, 2020 at 01:55:15AM -0700, Liu Yi L wrote:
> > IOMMUs that support nesting translation needs report the capability
> > info to userspace, e.g. the format of first level/stage paging structures.
> >
> > This patch reports nesting info by DOMAIN_ATTR_NESTING. Caller can get
> > nesting info after setting DOMAIN_ATTR_NESTING.
> >
> > v2 -> v3:
> > *) remvoe cap/ecap_mask in iommu_nesting_info.
> > *) reuse DOMAIN_ATTR_NESTING to get nesting info.
> > *) return an empty iommu_nesting_info for SMMU drivers per Jean'
> >suggestion.
> >
> > 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
> > ---
> > drivers/iommu/arm-smmu-v3.c | 29 --
> > drivers/iommu/arm-smmu.c| 29 --
>
> Looks reasonable to me. Please move the SMMU changes to a separate patch
> and Cc the SMMU maintainers:
>
> Cc: Will Deacon
> Cc: Robin Murphy
got you. will do it.
Regards,
Yi Liu
> Thanks,
> Jean
>
> > include/uapi/linux/iommu.h | 59
> > +
> > 3 files changed, 113 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
> > index f578677..0c45d4d 100644
> > --- a/drivers/iommu/arm-smmu-v3.c
> > +++ b/drivers/iommu/arm-smmu-v3.c
> > @@ -3019,6 +3019,32 @@ static struct iommu_group
> *arm_smmu_device_group(struct device *dev)
> > return group;
> > }
> >
> > +static int arm_smmu_domain_nesting_info(struct arm_smmu_domain
> *smmu_domain,
> > + void *data)
> > +{
> > + struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
> > + u32 size;
> > +
> > + if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
> > + return -ENODEV;
> > +
> > + size = sizeof(struct iommu_nesting_info);
> > +
> > + /*
> > +* if provided buffer size is not equal to the size, should
> > +* return 0 and also the expected buffer size to caller.
> > +*/
> > + if (info->size != size) {
> > + info->size = size;
> > + return 0;
> > + }
> > +
> > + /* report an empty iommu_nesting_info for now */
> > + memset(info, 0x0, size);
> > + info->size = size;
> > + return 0;
> > +}
> > +
> > static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> > enum iommu_attr attr, void *data) { @@ -
> 3028,8 +3054,7 @@
> > static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> > case IOMMU_DOMAIN_UNMANAGED:
> > switch (attr) {
> > case DOMAIN_ATTR_NESTING:
> > - *(int *)data = (smmu_domain->stage ==
> ARM_SMMU_DOMAIN_NESTED);
> > - return 0;
> > + return arm_smmu_domain_nesting_info(smmu_domain,
> data);
> > default:
> > return -ENODEV;
> > }
> > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index
> > 243bc4c..908607d 100644
> > --- a/drivers/iommu/arm-smmu.c
> > +++ b/drivers/iommu/arm-smmu.c
> > @@ -1506,6 +1506,32 @@ static struct iommu_group
> *arm_smmu_device_group(struct device *dev)
> > return group;
> > }
> >
> > +static int arm_smmu_domain_nesting_info(struct arm_smmu_domain
> *smmu_domain,
> > + void *data)
> > +{
> > + struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
> > + u32 size;
> > +
> > + if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
> > + return -ENODEV;
> > +
> > + size = sizeof(struct iommu_nesting_info);
> > +
> > + /*
> > +* if provided buffer size is not equal to the size, should
> > +* return 0 and also the expected buffer size to caller.
> > +*/
> > + if (info->size != size) {
> > + info->size = size;
> > + return 0;
> > + }
> > +
> > + /* report an empty iommu_nesting_info for now */
> > + memset(info, 0x0, size);
> > + info->size = size;
> > + return 0;
> > +}
> > +
> > static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> > enum iommu_attr attr, void *data) { @@ -
> 1515,8 +1541,7 @@
> > static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> > case IOMMU_DOMAIN_UNMANAGED:
> > switch (attr) {
> > case DOMAIN_ATTR_NESTING:
> > - *(int *)data = (smmu_domain->stage ==
> ARM_SMMU_DOMAIN_NESTED);
> > - return 0;
> > + return arm_smmu_domain_nesting_info(smmu_domain,
> data);
> > default:
> > return -ENODEV;
> > }
> > diff --git a/include/uapi/linux/iommu.h b/include/uapi/linux/iommu.h
> > index 1afc661..898c99a 100644
> > ---
Re: [PATCH v3 02/14] iommu: Report domain nesting info
On 2020-06-26 08:47, Jean-Philippe Brucker wrote:
On Wed, Jun 24, 2020 at 01:55:15AM -0700, Liu Yi L wrote:
IOMMUs that support nesting translation needs report the capability info
to userspace, e.g. the format of first level/stage paging structures.
This patch reports nesting info by DOMAIN_ATTR_NESTING. Caller can get
nesting info after setting DOMAIN_ATTR_NESTING.
v2 -> v3:
*) remvoe cap/ecap_mask in iommu_nesting_info.
*) reuse DOMAIN_ATTR_NESTING to get nesting info.
*) return an empty iommu_nesting_info for SMMU drivers per Jean'
suggestion.
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
---
drivers/iommu/arm-smmu-v3.c | 29 --
drivers/iommu/arm-smmu.c| 29 --
Looks reasonable to me. Please move the SMMU changes to a separate patch
and Cc the SMMU maintainers:
Cheers Jean, I'll admit I've been skipping over a lot of these patches
lately :)
A couple of comments below...
Cc: Will Deacon
Cc: Robin Murphy
Thanks,
Jean
include/uapi/linux/iommu.h | 59 +
3 files changed, 113 insertions(+), 4 deletions(-)
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index f578677..0c45d4d 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -3019,6 +3019,32 @@ static struct iommu_group *arm_smmu_device_group(struct
device *dev)
return group;
}
+static int arm_smmu_domain_nesting_info(struct arm_smmu_domain *smmu_domain,
+ void *data)
+{
+ struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
+ u32 size;
+
+ if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
+ return -ENODEV;
+
+ size = sizeof(struct iommu_nesting_info);
+
+ /*
+* if provided buffer size is not equal to the size, should
+* return 0 and also the expected buffer size to caller.
+*/
+ if (info->size != size) {
+ info->size = size;
+ return 0;
+ }
+
+ /* report an empty iommu_nesting_info for now */
+ memset(info, 0x0, size);
+ info->size = size;
+ return 0;
+}
+
static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
enum iommu_attr attr, void *data)
{
@@ -3028,8 +3054,7 @@ static int arm_smmu_domain_get_attr(struct iommu_domain
*domain,
case IOMMU_DOMAIN_UNMANAGED:
switch (attr) {
case DOMAIN_ATTR_NESTING:
- *(int *)data = (smmu_domain->stage ==
ARM_SMMU_DOMAIN_NESTED);
- return 0;
+ return arm_smmu_domain_nesting_info(smmu_domain, data);
default:
return -ENODEV;
}
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 243bc4c..908607d 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1506,6 +1506,32 @@ static struct iommu_group *arm_smmu_device_group(struct
device *dev)
return group;
}
+static int arm_smmu_domain_nesting_info(struct arm_smmu_domain *smmu_domain,
+ void *data)
+{
+ struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
+ u32 size;
+
+ if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
+ return -ENODEV;
+
+ size = sizeof(struct iommu_nesting_info);
+
+ /*
+* if provided buffer size is not equal to the size, should
+* return 0 and also the expected buffer size to caller.
+*/
+ if (info->size != size) {
+ info->size = size;
+ return 0;
+ }
+
+ /* report an empty iommu_nesting_info for now */
+ memset(info, 0x0, size);
+ info->size = size;
+ return 0;
+}
+
static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
enum iommu_attr attr, void *data)
{
@@ -1515,8 +1541,7 @@ static int arm_smmu_domain_get_attr(struct iommu_domain
*domain,
case IOMMU_DOMAIN_UNMANAGED:
switch (attr) {
case DOMAIN_ATTR_NESTING:
- *(int *)data = (smmu_domain->stage ==
ARM_SMMU_DOMAIN_NESTED);
- return 0;
+ return arm_smmu_domain_nesting_info(smmu_domain, data);
default:
return -ENODEV;
}
diff --git a/include/uapi/linux/iommu.h b/include/uapi/linux/iommu.h
index 1afc661..898c99a 100644
--- a/include/uapi/linux/iommu.h
+++ b/include/uapi/linux/iommu.h
@@ -332,4 +332,63 @@ struct iommu_gpasid_bind_data {
} vendor;
};
+/*
+ * struct iommu_nesting_info - Information for nesting-capable IOMMU.
+ *
Re: [PATCH v3 02/14] iommu: Report domain nesting info
On Wed, Jun 24, 2020 at 01:55:15AM -0700, Liu Yi L wrote:
> IOMMUs that support nesting translation needs report the capability info
> to userspace, e.g. the format of first level/stage paging structures.
>
> This patch reports nesting info by DOMAIN_ATTR_NESTING. Caller can get
> nesting info after setting DOMAIN_ATTR_NESTING.
>
> v2 -> v3:
> *) remvoe cap/ecap_mask in iommu_nesting_info.
> *) reuse DOMAIN_ATTR_NESTING to get nesting info.
> *) return an empty iommu_nesting_info for SMMU drivers per Jean'
>suggestion.
>
> 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
> ---
> drivers/iommu/arm-smmu-v3.c | 29 --
> drivers/iommu/arm-smmu.c| 29 --
Looks reasonable to me. Please move the SMMU changes to a separate patch
and Cc the SMMU maintainers:
Cc: Will Deacon
Cc: Robin Murphy
Thanks,
Jean
> include/uapi/linux/iommu.h | 59
> +
> 3 files changed, 113 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
> index f578677..0c45d4d 100644
> --- a/drivers/iommu/arm-smmu-v3.c
> +++ b/drivers/iommu/arm-smmu-v3.c
> @@ -3019,6 +3019,32 @@ static struct iommu_group
> *arm_smmu_device_group(struct device *dev)
> return group;
> }
>
> +static int arm_smmu_domain_nesting_info(struct arm_smmu_domain *smmu_domain,
> + void *data)
> +{
> + struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
> + u32 size;
> +
> + if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
> + return -ENODEV;
> +
> + size = sizeof(struct iommu_nesting_info);
> +
> + /*
> + * if provided buffer size is not equal to the size, should
> + * return 0 and also the expected buffer size to caller.
> + */
> + if (info->size != size) {
> + info->size = size;
> + return 0;
> + }
> +
> + /* report an empty iommu_nesting_info for now */
> + memset(info, 0x0, size);
> + info->size = size;
> + return 0;
> +}
> +
> static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> enum iommu_attr attr, void *data)
> {
> @@ -3028,8 +3054,7 @@ static int arm_smmu_domain_get_attr(struct iommu_domain
> *domain,
> case IOMMU_DOMAIN_UNMANAGED:
> switch (attr) {
> case DOMAIN_ATTR_NESTING:
> - *(int *)data = (smmu_domain->stage ==
> ARM_SMMU_DOMAIN_NESTED);
> - return 0;
> + return arm_smmu_domain_nesting_info(smmu_domain, data);
> default:
> return -ENODEV;
> }
> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> index 243bc4c..908607d 100644
> --- a/drivers/iommu/arm-smmu.c
> +++ b/drivers/iommu/arm-smmu.c
> @@ -1506,6 +1506,32 @@ static struct iommu_group
> *arm_smmu_device_group(struct device *dev)
> return group;
> }
>
> +static int arm_smmu_domain_nesting_info(struct arm_smmu_domain *smmu_domain,
> + void *data)
> +{
> + struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
> + u32 size;
> +
> + if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
> + return -ENODEV;
> +
> + size = sizeof(struct iommu_nesting_info);
> +
> + /*
> + * if provided buffer size is not equal to the size, should
> + * return 0 and also the expected buffer size to caller.
> + */
> + if (info->size != size) {
> + info->size = size;
> + return 0;
> + }
> +
> + /* report an empty iommu_nesting_info for now */
> + memset(info, 0x0, size);
> + info->size = size;
> + return 0;
> +}
> +
> static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
> enum iommu_attr attr, void *data)
> {
> @@ -1515,8 +1541,7 @@ static int arm_smmu_domain_get_attr(struct iommu_domain
> *domain,
> case IOMMU_DOMAIN_UNMANAGED:
> switch (attr) {
> case DOMAIN_ATTR_NESTING:
> - *(int *)data = (smmu_domain->stage ==
> ARM_SMMU_DOMAIN_NESTED);
> - return 0;
> + return arm_smmu_domain_nesting_info(smmu_domain, data);
> default:
> return -ENODEV;
> }
> diff --git a/include/uapi/linux/iommu.h b/include/uapi/linux/iommu.h
> index 1afc661..898c99a 100644
> --- a/include/uapi/linux/iommu.h
> +++ b/include/uapi/linux/iommu.h
> @@ -332,4 +332,63 @@ struct iommu_gpasid_bind_data {
> } vendor;
> };
>
> +/*
> + * struct iommu_nesting_info - Information for nesting-capable IOMMU.
> + * user space
[PATCH v3 02/14] iommu: Report domain nesting info
IOMMUs that support nesting translation needs report the capability info
to userspace, e.g. the format of first level/stage paging structures.
This patch reports nesting info by DOMAIN_ATTR_NESTING. Caller can get
nesting info after setting DOMAIN_ATTR_NESTING.
v2 -> v3:
*) remvoe cap/ecap_mask in iommu_nesting_info.
*) reuse DOMAIN_ATTR_NESTING to get nesting info.
*) return an empty iommu_nesting_info for SMMU drivers per Jean'
suggestion.
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
---
drivers/iommu/arm-smmu-v3.c | 29 --
drivers/iommu/arm-smmu.c| 29 --
include/uapi/linux/iommu.h | 59 +
3 files changed, 113 insertions(+), 4 deletions(-)
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index f578677..0c45d4d 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -3019,6 +3019,32 @@ static struct iommu_group *arm_smmu_device_group(struct
device *dev)
return group;
}
+static int arm_smmu_domain_nesting_info(struct arm_smmu_domain *smmu_domain,
+ void *data)
+{
+ struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
+ u32 size;
+
+ if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
+ return -ENODEV;
+
+ size = sizeof(struct iommu_nesting_info);
+
+ /*
+* if provided buffer size is not equal to the size, should
+* return 0 and also the expected buffer size to caller.
+*/
+ if (info->size != size) {
+ info->size = size;
+ return 0;
+ }
+
+ /* report an empty iommu_nesting_info for now */
+ memset(info, 0x0, size);
+ info->size = size;
+ return 0;
+}
+
static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
enum iommu_attr attr, void *data)
{
@@ -3028,8 +3054,7 @@ static int arm_smmu_domain_get_attr(struct iommu_domain
*domain,
case IOMMU_DOMAIN_UNMANAGED:
switch (attr) {
case DOMAIN_ATTR_NESTING:
- *(int *)data = (smmu_domain->stage ==
ARM_SMMU_DOMAIN_NESTED);
- return 0;
+ return arm_smmu_domain_nesting_info(smmu_domain, data);
default:
return -ENODEV;
}
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 243bc4c..908607d 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1506,6 +1506,32 @@ static struct iommu_group *arm_smmu_device_group(struct
device *dev)
return group;
}
+static int arm_smmu_domain_nesting_info(struct arm_smmu_domain *smmu_domain,
+ void *data)
+{
+ struct iommu_nesting_info *info = (struct iommu_nesting_info *) data;
+ u32 size;
+
+ if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
+ return -ENODEV;
+
+ size = sizeof(struct iommu_nesting_info);
+
+ /*
+* if provided buffer size is not equal to the size, should
+* return 0 and also the expected buffer size to caller.
+*/
+ if (info->size != size) {
+ info->size = size;
+ return 0;
+ }
+
+ /* report an empty iommu_nesting_info for now */
+ memset(info, 0x0, size);
+ info->size = size;
+ return 0;
+}
+
static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
enum iommu_attr attr, void *data)
{
@@ -1515,8 +1541,7 @@ static int arm_smmu_domain_get_attr(struct iommu_domain
*domain,
case IOMMU_DOMAIN_UNMANAGED:
switch (attr) {
case DOMAIN_ATTR_NESTING:
- *(int *)data = (smmu_domain->stage ==
ARM_SMMU_DOMAIN_NESTED);
- return 0;
+ return arm_smmu_domain_nesting_info(smmu_domain, data);
default:
return -ENODEV;
}
diff --git a/include/uapi/linux/iommu.h b/include/uapi/linux/iommu.h
index 1afc661..898c99a 100644
--- a/include/uapi/linux/iommu.h
+++ b/include/uapi/linux/iommu.h
@@ -332,4 +332,63 @@ struct iommu_gpasid_bind_data {
} vendor;
};
+/*
+ * struct iommu_nesting_info - Information for nesting-capable IOMMU.
+ * user space should check it before using
+ * nesting capability.
+ *
+ * @size: size of the whole structure
+ * @format:PASID table entry format, the same definition with
+ * @format of struct iommu_gpasid_bind_data.
+ * @features: supported nesting features.
+ * @flags: currently reserved for future extension.
+ * @data:
