diff options
Diffstat (limited to 'drivers/iommu/iommu.c')
-rw-r--r-- | drivers/iommu/iommu.c | 211 |
1 files changed, 202 insertions, 9 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 109de67d5d72..67ee6623f9b2 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -45,10 +45,6 @@ static unsigned int iommu_def_domain_type = IOMMU_DOMAIN_DMA; #endif static bool iommu_dma_strict __read_mostly = true; -struct iommu_callback_data { - const struct iommu_ops *ops; -}; - struct iommu_group { struct kobject kobj; struct kobject *devices_kobj; @@ -1217,9 +1213,6 @@ static int iommu_bus_init(struct bus_type *bus, const struct iommu_ops *ops) { int err; struct notifier_block *nb; - struct iommu_callback_data cb = { - .ops = ops, - }; nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL); if (!nb) @@ -1231,7 +1224,7 @@ static int iommu_bus_init(struct bus_type *bus, const struct iommu_ops *ops) if (err) goto out_free; - err = bus_for_each_dev(bus, NULL, &cb, add_iommu_group); + err = bus_for_each_dev(bus, NULL, NULL, add_iommu_group); if (err) goto out_err; @@ -1240,7 +1233,7 @@ static int iommu_bus_init(struct bus_type *bus, const struct iommu_ops *ops) out_err: /* Clean up */ - bus_for_each_dev(bus, NULL, &cb, remove_iommu_group); + bus_for_each_dev(bus, NULL, NULL, remove_iommu_group); bus_unregister_notifier(bus, nb); out_free: @@ -2039,3 +2032,203 @@ 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); + +/** + * iommu_sva_bind_device() - Bind a process address space to a device + * @dev: the device + * @mm: the mm to bind, caller must hold a reference to it + * + * Create a bond between device and address space, allowing the device to access + * the mm using the returned PASID. If a bond already exists between @device and + * @mm, it is returned and an additional reference is taken. Caller must call + * iommu_sva_unbind_device() to release each reference. + * + * iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA) must be called first, to + * initialize the required SVA features. + * + * On error, returns an ERR_PTR value. + */ +struct iommu_sva * +iommu_sva_bind_device(struct device *dev, struct mm_struct *mm, void *drvdata) +{ + struct iommu_group *group; + struct iommu_sva *handle = ERR_PTR(-EINVAL); + const struct iommu_ops *ops = dev->bus->iommu_ops; + + if (!ops || !ops->sva_bind) + return ERR_PTR(-ENODEV); + + group = iommu_group_get(dev); + if (!group) + return ERR_PTR(-ENODEV); + + /* Ensure device count and domain don't change while we're binding */ + mutex_lock(&group->mutex); + + /* + * To keep things simple, SVA currently doesn't support IOMMU groups + * with more than one device. Existing SVA-capable systems are not + * affected by the problems that required IOMMU groups (lack of ACS + * isolation, device ID aliasing and other hardware issues). + */ + if (iommu_group_device_count(group) != 1) + goto out_unlock; + + handle = ops->sva_bind(dev, mm, drvdata); + +out_unlock: + mutex_unlock(&group->mutex); + iommu_group_put(group); + + return handle; +} +EXPORT_SYMBOL_GPL(iommu_sva_bind_device); + +/** + * iommu_sva_unbind_device() - Remove a bond created with iommu_sva_bind_device + * @handle: the handle returned by iommu_sva_bind_device() + * + * Put reference to a bond between device and address space. The device should + * not be issuing any more transaction for this PASID. All outstanding page + * requests for this PASID must have been flushed to the IOMMU. + * + * Returns 0 on success, or an error value + */ +void iommu_sva_unbind_device(struct iommu_sva *handle) +{ + struct iommu_group *group; + struct device *dev = handle->dev; + const struct iommu_ops *ops = dev->bus->iommu_ops; + + if (!ops || !ops->sva_unbind) + return; + + group = iommu_group_get(dev); + if (!group) + return; + + mutex_lock(&group->mutex); + ops->sva_unbind(handle); + mutex_unlock(&group->mutex); + + iommu_group_put(group); +} +EXPORT_SYMBOL_GPL(iommu_sva_unbind_device); + +int iommu_sva_set_ops(struct iommu_sva *handle, + const struct iommu_sva_ops *sva_ops) +{ + if (handle->ops && handle->ops != sva_ops) + return -EEXIST; + + handle->ops = sva_ops; + return 0; +} +EXPORT_SYMBOL_GPL(iommu_sva_set_ops); + +int iommu_sva_get_pasid(struct iommu_sva *handle) +{ + const struct iommu_ops *ops = handle->dev->bus->iommu_ops; + + if (!ops || !ops->sva_get_pasid) + return IOMMU_PASID_INVALID; + + return ops->sva_get_pasid(handle); +} +EXPORT_SYMBOL_GPL(iommu_sva_get_pasid); |