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);
struct device;
struct iommu_domain;
struct notifier_block;
+struct iommu_sva;
/* iommu fault flags */
#define IOMMU_FAULT_READ 0x0
typedef int (*iommu_fault_handler_t)(struct iommu_domain *,
struct device *, unsigned long, int, void *);
+typedef int (*iommu_mm_exit_handler_t)(struct device *dev, struct iommu_sva *,
+ void *);
struct iommu_domain_geometry {
dma_addr_t aperture_start; /* First address that can be mapped */
/* Per device IOMMU features */
enum iommu_dev_features {
IOMMU_DEV_FEAT_AUX, /* Aux-domain feature */
+ IOMMU_DEV_FEAT_SVA, /* Shared Virtual Addresses */
+};
+
+#define IOMMU_PASID_INVALID (-1U)
+
+/**
+ * struct iommu_sva_ops - device driver callbacks for an SVA context
+ *
+ * @mm_exit: called when the mm is about to be torn down by exit_mmap. After
+ * @mm_exit returns, the device must not issue any more transaction
+ * with the PASID given as argument.
+ *
+ * The @mm_exit handler is allowed to sleep. Be careful about the
+ * locks taken in @mm_exit, because they might lead to deadlocks if
+ * they are also held when dropping references to the mm. Consider the
+ * following call chain:
+ * mutex_lock(A); mmput(mm) -> exit_mm() -> @mm_exit() -> mutex_lock(A)
+ * Using mmput_async() prevents this scenario.
+ *
+ */
+struct iommu_sva_ops {
+ iommu_mm_exit_handler_t mm_exit;
};
#ifdef CONFIG_IOMMU_API
* @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
+ * @sva_bind: Bind process address space to device
+ * @sva_unbind: Unbind process address space from device
+ * @sva_get_pasid: Get PASID associated to a SVA handle
* @pgsize_bitmap: bitmap of all possible supported page sizes
*/
struct iommu_ops {
void (*aux_detach_dev)(struct iommu_domain *domain, struct device *dev);
int (*aux_get_pasid)(struct iommu_domain *domain, struct device *dev);
+ struct iommu_sva *(*sva_bind)(struct device *dev, struct mm_struct *mm,
+ void *drvdata);
+ void (*sva_unbind)(struct iommu_sva *handle);
+ int (*sva_get_pasid)(struct iommu_sva *handle);
+
unsigned long pgsize_bitmap;
};
u32 ids[1];
};
+/**
+ * struct iommu_sva - handle to a device-mm bond
+ */
+struct iommu_sva {
+ struct device *dev;
+ const struct iommu_sva_ops *ops;
+};
+
int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode,
const struct iommu_ops *ops);
void iommu_fwspec_free(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);
+struct iommu_sva *iommu_sva_bind_device(struct device *dev,
+ struct mm_struct *mm,
+ void *drvdata);
+void iommu_sva_unbind_device(struct iommu_sva *handle);
+int iommu_sva_set_ops(struct iommu_sva *handle,
+ const struct iommu_sva_ops *ops);
+int iommu_sva_get_pasid(struct iommu_sva *handle);
+
#else /* CONFIG_IOMMU_API */
struct iommu_ops {};
return -ENODEV;
}
+static inline struct iommu_sva *
+iommu_sva_bind_device(struct device *dev, struct mm_struct *mm, void *drvdata)
+{
+ return NULL;
+}
+
+static inline void iommu_sva_unbind_device(struct iommu_sva *handle)
+{
+}
+
+static inline int iommu_sva_set_ops(struct iommu_sva *handle,
+ const struct iommu_sva_ops *ops)
+{
+ return -EINVAL;
+}
+
+static inline int iommu_sva_get_pasid(struct iommu_sva *handle)
+{
+ return IOMMU_PASID_INVALID;
+}
+
#endif /* CONFIG_IOMMU_API */
#ifdef CONFIG_IOMMU_DEBUGFS