diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 109de67d5d72..344e27e8f188 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -2039,3 +2039,99 @@ int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids) return 0; } EXPORT_SYMBOL_GPL(iommu_fwspec_add_ids); + +/* + * Per device IOMMU features. + */ +bool iommu_dev_has_feature(struct device *dev, enum iommu_dev_features feat) +{ + const struct iommu_ops *ops = dev->bus->iommu_ops; + + if (ops && ops->dev_has_feat) + return ops->dev_has_feat(dev, feat); + + return false; +} +EXPORT_SYMBOL_GPL(iommu_dev_has_feature); + +int iommu_dev_enable_feature(struct device *dev, enum iommu_dev_features feat) +{ + const struct iommu_ops *ops = dev->bus->iommu_ops; + + if (ops && ops->dev_enable_feat) + return ops->dev_enable_feat(dev, feat); + + return -ENODEV; +} +EXPORT_SYMBOL_GPL(iommu_dev_enable_feature); + +/* + * The device drivers should do the necessary cleanups before calling this. + * For example, before disabling the aux-domain feature, the device driver + * should detach all aux-domains. Otherwise, this will return -EBUSY. + */ +int iommu_dev_disable_feature(struct device *dev, enum iommu_dev_features feat) +{ + const struct iommu_ops *ops = dev->bus->iommu_ops; + + if (ops && ops->dev_disable_feat) + return ops->dev_disable_feat(dev, feat); + + return -EBUSY; +} +EXPORT_SYMBOL_GPL(iommu_dev_disable_feature); + +bool iommu_dev_feature_enabled(struct device *dev, enum iommu_dev_features feat) +{ + const struct iommu_ops *ops = dev->bus->iommu_ops; + + if (ops && ops->dev_feat_enabled) + return ops->dev_feat_enabled(dev, feat); + + return false; +} +EXPORT_SYMBOL_GPL(iommu_dev_feature_enabled); + +/* + * Aux-domain specific attach/detach. + * + * Only works if iommu_dev_feature_enabled(dev, IOMMU_DEV_FEAT_AUX) returns + * true. Also, as long as domains are attached to a device through this + * interface, any tries to call iommu_attach_device() should fail + * (iommu_detach_device() can't fail, so we fail when trying to re-attach). + * This should make us safe against a device being attached to a guest as a + * whole while there are still pasid users on it (aux and sva). + */ +int iommu_aux_attach_device(struct iommu_domain *domain, struct device *dev) +{ + int ret = -ENODEV; + + if (domain->ops->aux_attach_dev) + ret = domain->ops->aux_attach_dev(domain, dev); + + if (!ret) + trace_attach_device_to_domain(dev); + + return ret; +} +EXPORT_SYMBOL_GPL(iommu_aux_attach_device); + +void iommu_aux_detach_device(struct iommu_domain *domain, struct device *dev) +{ + if (domain->ops->aux_detach_dev) { + domain->ops->aux_detach_dev(domain, dev); + trace_detach_device_from_domain(dev); + } +} +EXPORT_SYMBOL_GPL(iommu_aux_detach_device); + +int iommu_aux_get_pasid(struct iommu_domain *domain, struct device *dev) +{ + int ret = -ENODEV; + + if (domain->ops->aux_get_pasid) + ret = domain->ops->aux_get_pasid(domain, dev); + + return ret; +} +EXPORT_SYMBOL_GPL(iommu_aux_get_pasid); diff --git a/include/linux/iommu.h b/include/linux/iommu.h index ffbbc7e39cee..8239ece9fdfc 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -156,6 +156,11 @@ struct iommu_resv_region { enum iommu_resv_type type; }; +/* Per device IOMMU features */ +enum iommu_dev_features { + IOMMU_DEV_FEAT_AUX, /* Aux-domain feature */ +}; + #ifdef CONFIG_IOMMU_API /** @@ -186,6 +191,11 @@ struct iommu_resv_region { * @of_xlate: add OF master IDs to iommu grouping * @is_attach_deferred: Check if domain attach should be deferred from iommu * driver init to device driver init (default no) + * @dev_has/enable/disable_feat: per device entries to check/enable/disable + * iommu specific features. + * @dev_feat_enabled: check enabled feature + * @aux_attach/detach_dev: aux-domain specific attach/detach entries. + * @aux_get_pasid: get the pasid given an aux-domain * @pgsize_bitmap: bitmap of all possible supported page sizes */ struct iommu_ops { @@ -230,6 +240,17 @@ struct iommu_ops { int (*of_xlate)(struct device *dev, struct of_phandle_args *args); bool (*is_attach_deferred)(struct iommu_domain *domain, struct device *dev); + /* Per device IOMMU features */ + bool (*dev_has_feat)(struct device *dev, enum iommu_dev_features f); + bool (*dev_feat_enabled)(struct device *dev, enum iommu_dev_features f); + int (*dev_enable_feat)(struct device *dev, enum iommu_dev_features f); + int (*dev_disable_feat)(struct device *dev, enum iommu_dev_features f); + + /* Aux-domain specific attach/detach entries */ + int (*aux_attach_dev)(struct iommu_domain *domain, struct device *dev); + void (*aux_detach_dev)(struct iommu_domain *domain, struct device *dev); + int (*aux_get_pasid)(struct iommu_domain *domain, struct device *dev); + unsigned long pgsize_bitmap; }; @@ -416,6 +437,14 @@ static inline void dev_iommu_fwspec_set(struct device *dev, int iommu_probe_device(struct device *dev); void iommu_release_device(struct device *dev); +bool iommu_dev_has_feature(struct device *dev, enum iommu_dev_features f); +int iommu_dev_enable_feature(struct device *dev, enum iommu_dev_features f); +int iommu_dev_disable_feature(struct device *dev, enum iommu_dev_features f); +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); + #else /* CONFIG_IOMMU_API */ struct iommu_ops {}; @@ -700,6 +729,47 @@ const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode) return NULL; } +static inline bool +iommu_dev_has_feature(struct device *dev, enum iommu_dev_features feat) +{ + return false; +} + +static inline bool +iommu_dev_feature_enabled(struct device *dev, enum iommu_dev_features feat) +{ + return false; +} + +static inline int +iommu_dev_enable_feature(struct device *dev, enum iommu_dev_features feat) +{ + return -ENODEV; +} + +static inline int +iommu_dev_disable_feature(struct device *dev, enum iommu_dev_features feat) +{ + return -ENODEV; +} + +static inline int +iommu_aux_attach_device(struct iommu_domain *domain, struct device *dev) +{ + return -ENODEV; +} + +static inline void +iommu_aux_detach_device(struct iommu_domain *domain, struct device *dev) +{ +} + +static inline int +iommu_aux_get_pasid(struct iommu_domain *domain, struct device *dev) +{ + return -ENODEV; +} + #endif /* CONFIG_IOMMU_API */ #ifdef CONFIG_IOMMU_DEBUGFS