This adds two new aux-domain APIs for a use case like vfio/mdev where sub-devices derived from an aux-domain capable device are created and put in an iommu_group.
/** * iommu_aux_attach_group - attach an aux-domain to an iommu_group which * contains sub-devices (for example mdevs) derived * from @dev. * @domain: an aux-domain; * @group: an iommu_group which contains sub-devices derived from @dev; * @dev: the physical device which supports IOMMU_DEV_FEAT_AUX. * * Returns 0 on success, or an error value. */ int iommu_aux_attach_group(struct iommu_domain *domain, struct iommu_group *group, struct device *dev) /** * iommu_aux_detach_group - detach an aux-domain from an iommu_group * * @domain: an aux-domain; * @group: an iommu_group which contains sub-devices derived from @dev; * @dev: the physical device which supports IOMMU_DEV_FEAT_AUX. * * @domain must have been attached to @group via iommu_aux_attach_group(). */ void iommu_aux_detach_group(struct iommu_domain *domain, struct iommu_group *group, struct device *dev) It also adds a flag in the iommu_group data structure to identify an iommu_group with aux-domain attached from those normal ones. Signed-off-by: Lu Baolu <baolu...@linux.intel.com> --- drivers/iommu/iommu.c | 58 +++++++++++++++++++++++++++++++++++++++++++ include/linux/iommu.h | 17 +++++++++++++ 2 files changed, 75 insertions(+) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index e1fdd3531d65..cad5a19ebf22 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -45,6 +45,7 @@ struct iommu_group { struct iommu_domain *default_domain; struct iommu_domain *domain; struct list_head entry; + unsigned int aux_domain_attached:1; }; struct group_device { @@ -2759,6 +2760,63 @@ int iommu_aux_get_pasid(struct iommu_domain *domain, struct device *dev) } EXPORT_SYMBOL_GPL(iommu_aux_get_pasid); +/** + * iommu_aux_attach_group - attach an aux-domain to an iommu_group which + * contains sub-devices (for example mdevs) derived + * from @dev. + * @domain: an aux-domain; + * @group: an iommu_group which contains sub-devices derived from @dev; + * @dev: the physical device which supports IOMMU_DEV_FEAT_AUX. + * + * Returns 0 on success, or an error value. + */ +int iommu_aux_attach_group(struct iommu_domain *domain, + struct iommu_group *group, struct device *dev) +{ + int ret = -EBUSY; + + mutex_lock(&group->mutex); + if (group->domain) + goto out_unlock; + + ret = iommu_aux_attach_device(domain, dev); + if (!ret) { + group->domain = domain; + group->aux_domain_attached = true; + } + +out_unlock: + mutex_unlock(&group->mutex); + return ret; +} +EXPORT_SYMBOL_GPL(iommu_aux_attach_group); + +/** + * iommu_aux_detach_group - detach an aux-domain from an iommu_group + * + * @domain: an aux-domain; + * @group: an iommu_group which contains sub-devices derived from @dev; + * @dev: the physical device which supports IOMMU_DEV_FEAT_AUX. + * + * @domain must have been attached to @group via iommu_aux_attach_group(). + */ +void iommu_aux_detach_group(struct iommu_domain *domain, + struct iommu_group *group, struct device *dev) +{ + mutex_lock(&group->mutex); + + if (WARN_ON(!group->aux_domain_attached || group->domain != domain)) + goto out_unlock; + + iommu_aux_detach_device(domain, dev); + group->aux_domain_attached = false; + group->domain = NULL; + +out_unlock: + mutex_unlock(&group->mutex); +} +EXPORT_SYMBOL_GPL(iommu_aux_detach_group); + /** * iommu_sva_bind_device() - Bind a process address space to a device * @dev: the device diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 5657d4fef9f2..9506551139ab 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -635,6 +635,10 @@ bool iommu_dev_feature_enabled(struct device *dev, enum iommu_dev_features f); int iommu_aux_attach_device(struct iommu_domain *domain, struct device *dev); void iommu_aux_detach_device(struct iommu_domain *domain, struct device *dev); int iommu_aux_get_pasid(struct iommu_domain *domain, struct device *dev); +int iommu_aux_attach_group(struct iommu_domain *domain, + struct iommu_group *group, struct device *dev); +void iommu_aux_detach_group(struct iommu_domain *domain, + struct iommu_group *group, struct device *dev); struct iommu_sva *iommu_sva_bind_device(struct device *dev, struct mm_struct *mm, @@ -1023,6 +1027,19 @@ iommu_aux_get_pasid(struct iommu_domain *domain, struct device *dev) return -ENODEV; } +static inline int +iommu_aux_attach_group(struct iommu_domain *domain, + struct iommu_group *group, struct device *dev) +{ + return -ENODEV; +} + +static inline void +iommu_aux_detach_group(struct iommu_domain *domain, + struct iommu_group *group, struct device *dev) +{ +} + static inline struct iommu_sva * iommu_sva_bind_device(struct device *dev, struct mm_struct *mm, void *drvdata) { -- 2.17.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu