v4.19.13 snapshot.
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
new file mode 100644
index 0000000..66741ab
--- /dev/null
+++ b/include/linux/vfio.h
@@ -0,0 +1,201 @@
+/*
+ * VFIO API definition
+ *
+ * Copyright (C) 2012 Red Hat, Inc.  All rights reserved.
+ *     Author: Alex Williamson <alex.williamson@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef VFIO_H
+#define VFIO_H
+
+
+#include <linux/iommu.h>
+#include <linux/mm.h>
+#include <linux/workqueue.h>
+#include <linux/poll.h>
+#include <uapi/linux/vfio.h>
+
+/**
+ * struct vfio_device_ops - VFIO bus driver device callbacks
+ *
+ * @open: Called when userspace creates new file descriptor for device
+ * @release: Called when userspace releases file descriptor for device
+ * @read: Perform read(2) on device file descriptor
+ * @write: Perform write(2) on device file descriptor
+ * @ioctl: Perform ioctl(2) on device file descriptor, supporting VFIO_DEVICE_*
+ *         operations documented below
+ * @mmap: Perform mmap(2) on a region of the device file descriptor
+ * @request: Request for the bus driver to release the device
+ */
+struct vfio_device_ops {
+	char	*name;
+	int	(*open)(void *device_data);
+	void	(*release)(void *device_data);
+	ssize_t	(*read)(void *device_data, char __user *buf,
+			size_t count, loff_t *ppos);
+	ssize_t	(*write)(void *device_data, const char __user *buf,
+			 size_t count, loff_t *size);
+	long	(*ioctl)(void *device_data, unsigned int cmd,
+			 unsigned long arg);
+	int	(*mmap)(void *device_data, struct vm_area_struct *vma);
+	void	(*request)(void *device_data, unsigned int count);
+};
+
+extern struct iommu_group *vfio_iommu_group_get(struct device *dev);
+extern void vfio_iommu_group_put(struct iommu_group *group, struct device *dev);
+
+extern int vfio_add_group_dev(struct device *dev,
+			      const struct vfio_device_ops *ops,
+			      void *device_data);
+
+extern void *vfio_del_group_dev(struct device *dev);
+extern struct vfio_device *vfio_device_get_from_dev(struct device *dev);
+extern void vfio_device_put(struct vfio_device *device);
+extern void *vfio_device_data(struct vfio_device *device);
+
+/**
+ * struct vfio_iommu_driver_ops - VFIO IOMMU driver callbacks
+ */
+struct vfio_iommu_driver_ops {
+	char		*name;
+	struct module	*owner;
+	void		*(*open)(unsigned long arg);
+	void		(*release)(void *iommu_data);
+	ssize_t		(*read)(void *iommu_data, char __user *buf,
+				size_t count, loff_t *ppos);
+	ssize_t		(*write)(void *iommu_data, const char __user *buf,
+				 size_t count, loff_t *size);
+	long		(*ioctl)(void *iommu_data, unsigned int cmd,
+				 unsigned long arg);
+	int		(*mmap)(void *iommu_data, struct vm_area_struct *vma);
+	int		(*attach_group)(void *iommu_data,
+					struct iommu_group *group);
+	void		(*detach_group)(void *iommu_data,
+					struct iommu_group *group);
+	int		(*pin_pages)(void *iommu_data, unsigned long *user_pfn,
+				     int npage, int prot,
+				     unsigned long *phys_pfn);
+	int		(*unpin_pages)(void *iommu_data,
+				       unsigned long *user_pfn, int npage);
+	int		(*register_notifier)(void *iommu_data,
+					     unsigned long *events,
+					     struct notifier_block *nb);
+	int		(*unregister_notifier)(void *iommu_data,
+					       struct notifier_block *nb);
+};
+
+extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
+
+extern void vfio_unregister_iommu_driver(
+				const struct vfio_iommu_driver_ops *ops);
+
+/*
+ * External user API
+ */
+extern struct vfio_group *vfio_group_get_external_user(struct file *filep);
+extern void vfio_group_put_external_user(struct vfio_group *group);
+extern bool vfio_external_group_match_file(struct vfio_group *group,
+					   struct file *filep);
+extern int vfio_external_user_iommu_id(struct vfio_group *group);
+extern long vfio_external_check_extension(struct vfio_group *group,
+					  unsigned long arg);
+
+#define VFIO_PIN_PAGES_MAX_ENTRIES	(PAGE_SIZE/sizeof(unsigned long))
+
+extern int vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
+			  int npage, int prot, unsigned long *phys_pfn);
+extern int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn,
+			    int npage);
+
+/* each type has independent events */
+enum vfio_notify_type {
+	VFIO_IOMMU_NOTIFY = 0,
+	VFIO_GROUP_NOTIFY = 1,
+};
+
+/* events for VFIO_IOMMU_NOTIFY */
+#define VFIO_IOMMU_NOTIFY_DMA_UNMAP	BIT(0)
+
+/* events for VFIO_GROUP_NOTIFY */
+#define VFIO_GROUP_NOTIFY_SET_KVM	BIT(0)
+
+extern int vfio_register_notifier(struct device *dev,
+				  enum vfio_notify_type type,
+				  unsigned long *required_events,
+				  struct notifier_block *nb);
+extern int vfio_unregister_notifier(struct device *dev,
+				    enum vfio_notify_type type,
+				    struct notifier_block *nb);
+
+struct kvm;
+extern void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm);
+
+/*
+ * Sub-module helpers
+ */
+struct vfio_info_cap {
+	struct vfio_info_cap_header *buf;
+	size_t size;
+};
+extern struct vfio_info_cap_header *vfio_info_cap_add(
+		struct vfio_info_cap *caps, size_t size, u16 id, u16 version);
+extern void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset);
+
+extern int vfio_info_add_capability(struct vfio_info_cap *caps,
+				    struct vfio_info_cap_header *cap,
+				    size_t size);
+
+extern int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr,
+					      int num_irqs, int max_irq_type,
+					      size_t *data_size);
+
+struct pci_dev;
+#if IS_ENABLED(CONFIG_VFIO_SPAPR_EEH)
+extern void vfio_spapr_pci_eeh_open(struct pci_dev *pdev);
+extern void vfio_spapr_pci_eeh_release(struct pci_dev *pdev);
+extern long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
+				       unsigned int cmd,
+				       unsigned long arg);
+#else
+static inline void vfio_spapr_pci_eeh_open(struct pci_dev *pdev)
+{
+}
+
+static inline void vfio_spapr_pci_eeh_release(struct pci_dev *pdev)
+{
+}
+
+static inline long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
+					      unsigned int cmd,
+					      unsigned long arg)
+{
+	return -ENOTTY;
+}
+#endif /* CONFIG_VFIO_SPAPR_EEH */
+
+/*
+ * IRQfd - generic
+ */
+struct virqfd {
+	void			*opaque;
+	struct eventfd_ctx	*eventfd;
+	int			(*handler)(void *, void *);
+	void			(*thread)(void *, void *);
+	void			*data;
+	struct work_struct	inject;
+	wait_queue_entry_t		wait;
+	poll_table		pt;
+	struct work_struct	shutdown;
+	struct virqfd		**pvirqfd;
+};
+
+extern int vfio_virqfd_enable(void *opaque,
+			      int (*handler)(void *, void *),
+			      void (*thread)(void *, void *),
+			      void *data, struct virqfd **pvirqfd, int fd);
+extern void vfio_virqfd_disable(struct virqfd **pvirqfd);
+
+#endif /* VFIO_H */