Merge pull request #493 from swapnili/use-linux-vfio-header

Use linux vfio header

3 files changed, 1308 insertions, 61 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8715625..768d1a6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -40,6 +40,7 @@ find_package(PkgConfig REQUIRED)
 pkg_check_modules(JSON REQUIRED json-c)
 
 include_directories(${CMAKE_SOURCE_DIR}/include)
+include_directories(${CMAKE_SOURCE_DIR}/linux-headers/)
 include_directories(${CMAKE_SOURCE_DIR}/lib)
 include_directories(${JSON_INCLUDE_DIRS})
 
diff --git a/include/vfio-user.h b/include/vfio-user.h
index 053ead2..09a756e 100644
--- a/include/vfio-user.h
+++ b/include/vfio-user.h
@@ -133,67 +133,6 @@ struct vfio_user_irq_info {
     uint32_t    subindex;
 } __attribute__((packed));
 
-#if LINUX_VERSION_CODE < KERNEL_VERSION(5,8,0)
-
-/* copied from <linux/vfio.h> */
-
-#define VFIO_DEVICE_STATE_STOP      (0)
-#define VFIO_DEVICE_STATE_RUNNING   (1 << 0)
-#define VFIO_DEVICE_STATE_SAVING    (1 << 1)
-#define VFIO_DEVICE_STATE_RESUMING  (1 << 2)
-#define VFIO_DEVICE_STATE_MASK      (VFIO_DEVICE_STATE_RUNNING | \
-				     VFIO_DEVICE_STATE_SAVING |  \
-				     VFIO_DEVICE_STATE_RESUMING)
-
-#define VFIO_DEVICE_STATE_VALID(state) \
-	(state & VFIO_DEVICE_STATE_RESUMING ? \
-	(state & VFIO_DEVICE_STATE_MASK) == VFIO_DEVICE_STATE_RESUMING : 1)
-
-#define VFIO_DEVICE_STATE_IS_ERROR(state) \
-	((state & VFIO_DEVICE_STATE_MASK) == (VFIO_DEVICE_STATE_SAVING | \
-					      VFIO_DEVICE_STATE_RESUMING))
-
-#define VFIO_DEVICE_STATE_SET_ERROR(state) \
-	((state & ~VFIO_DEVICE_STATE_MASK) | VFIO_DEVICE_SATE_SAVING | \
-					     VFIO_DEVICE_STATE_RESUMING)
-
-/* RHEL kernels have some of it backported */
-#ifndef VFIO_REGION_TYPE_MIGRATION /* not a RHEL kernel */
-#define VFIO_REGION_TYPE_MIGRATION              (3)
-#define VFIO_REGION_SUBTYPE_MIGRATION           (1)
-
-struct vfio_device_migration_info {
-	__u32 device_state;         /* VFIO device state */
-	__u32 reserved;
-	__u64 pending_bytes;
-	__u64 data_offset;
-	__u64 data_size;
-};
-#endif /* not a RHEL kernel */
-
-struct vfio_bitmap {
-	__u64        pgsize;	/* page size for bitmap in bytes */
-	__u64        size;	/* in bytes */
-	__u64 *data;	/* one bit per page */
-};
-
-struct vfio_iommu_type1_dirty_bitmap {
-	__u32        argsz;
-	__u32        flags;
-#define VFIO_IOMMU_DIRTY_PAGES_FLAG_START	(1 << 0)
-#define VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP	(1 << 1)
-#define VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP	(1 << 2)
-	__u8         data[];
-};
-
-struct vfio_iommu_type1_dirty_bitmap_get {
-	__u64              iova;	/* IO virtual address */
-	__u64              size;	/* Size of iova range */
-	struct vfio_bitmap bitmap;
-};
-
-#endif /* LINUX_VERSION_CODE < KERNEL_VERSION(5,8,0) */
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/linux-headers/linux/vfio.h b/linux-headers/linux/vfio.h
new file mode 100644
index 0000000..1b22c22
--- /dev/null
+++ b/linux-headers/linux/vfio.h
@@ -0,0 +1,1307 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * 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/types.h>
+#include <linux/ioctl.h>
+
+#define VFIO_API_VERSION	0
+
+
+/* Kernel & User level defines for VFIO IOCTLs. */
+
+/* Extensions */
+
+#define VFIO_TYPE1_IOMMU		1
+#define VFIO_SPAPR_TCE_IOMMU		2
+#define VFIO_TYPE1v2_IOMMU		3
+/*
+ * IOMMU enforces DMA cache coherence (ex. PCIe NoSnoop stripping).  This
+ * capability is subject to change as groups are added or removed.
+ */
+#define VFIO_DMA_CC_IOMMU		4
+
+/* Check if EEH is supported */
+#define VFIO_EEH			5
+
+/* Two-stage IOMMU */
+#define VFIO_TYPE1_NESTING_IOMMU	6	/* Implies v2 */
+
+#define VFIO_SPAPR_TCE_v2_IOMMU		7
+
+/*
+ * The No-IOMMU IOMMU offers no translation or isolation for devices and
+ * supports no ioctls outside of VFIO_CHECK_EXTENSION.  Use of VFIO's No-IOMMU
+ * code will taint the host kernel and should be used with extreme caution.
+ */
+#define VFIO_NOIOMMU_IOMMU		8
+
+/*
+ * The IOCTL interface is designed for extensibility by embedding the
+ * structure length (argsz) and flags into structures passed between
+ * kernel and userspace.  We therefore use the _IO() macro for these
+ * defines to avoid implicitly embedding a size into the ioctl request.
+ * As structure fields are added, argsz will increase to match and flag
+ * bits will be defined to indicate additional fields with valid data.
+ * It's *always* the caller's responsibility to indicate the size of
+ * the structure passed by setting argsz appropriately.
+ */
+
+#define VFIO_TYPE	(';')
+#define VFIO_BASE	100
+
+/*
+ * For extension of INFO ioctls, VFIO makes use of a capability chain
+ * designed after PCI/e capabilities.  A flag bit indicates whether
+ * this capability chain is supported and a field defined in the fixed
+ * structure defines the offset of the first capability in the chain.
+ * This field is only valid when the corresponding bit in the flags
+ * bitmap is set.  This offset field is relative to the start of the
+ * INFO buffer, as is the next field within each capability header.
+ * The id within the header is a shared address space per INFO ioctl,
+ * while the version field is specific to the capability id.  The
+ * contents following the header are specific to the capability id.
+ */
+struct vfio_info_cap_header {
+	__u16	id;		/* Identifies capability */
+	__u16	version;	/* Version specific to the capability ID */
+	__u32	next;		/* Offset of next capability */
+};
+
+/*
+ * Callers of INFO ioctls passing insufficiently sized buffers will see
+ * the capability chain flag bit set, a zero value for the first capability
+ * offset (if available within the provided argsz), and argsz will be
+ * updated to report the necessary buffer size.  For compatibility, the
+ * INFO ioctl will not report error in this case, but the capability chain
+ * will not be available.
+ */
+
+/* -------- IOCTLs for VFIO file descriptor (/dev/vfio/vfio) -------- */
+
+/**
+ * VFIO_GET_API_VERSION - _IO(VFIO_TYPE, VFIO_BASE + 0)
+ *
+ * Report the version of the VFIO API.  This allows us to bump the entire
+ * API version should we later need to add or change features in incompatible
+ * ways.
+ * Return: VFIO_API_VERSION
+ * Availability: Always
+ */
+#define VFIO_GET_API_VERSION		_IO(VFIO_TYPE, VFIO_BASE + 0)
+
+/**
+ * VFIO_CHECK_EXTENSION - _IOW(VFIO_TYPE, VFIO_BASE + 1, __u32)
+ *
+ * Check whether an extension is supported.
+ * Return: 0 if not supported, 1 (or some other positive integer) if supported.
+ * Availability: Always
+ */
+#define VFIO_CHECK_EXTENSION		_IO(VFIO_TYPE, VFIO_BASE + 1)
+
+/**
+ * VFIO_SET_IOMMU - _IOW(VFIO_TYPE, VFIO_BASE + 2, __s32)
+ *
+ * Set the iommu to the given type.  The type must be supported by an
+ * iommu driver as verified by calling CHECK_EXTENSION using the same
+ * type.  A group must be set to this file descriptor before this
+ * ioctl is available.  The IOMMU interfaces enabled by this call are
+ * specific to the value set.
+ * Return: 0 on success, -errno on failure
+ * Availability: When VFIO group attached
+ */
+#define VFIO_SET_IOMMU			_IO(VFIO_TYPE, VFIO_BASE + 2)
+
+/* -------- IOCTLs for GROUP file descriptors (/dev/vfio/$GROUP) -------- */
+
+/**
+ * VFIO_GROUP_GET_STATUS - _IOR(VFIO_TYPE, VFIO_BASE + 3,
+ *						struct vfio_group_status)
+ *
+ * Retrieve information about the group.  Fills in provided
+ * struct vfio_group_info.  Caller sets argsz.
+ * Return: 0 on succes, -errno on failure.
+ * Availability: Always
+ */
+struct vfio_group_status {
+	__u32	argsz;
+	__u32	flags;
+#define VFIO_GROUP_FLAGS_VIABLE		(1 << 0)
+#define VFIO_GROUP_FLAGS_CONTAINER_SET	(1 << 1)
+};
+#define VFIO_GROUP_GET_STATUS		_IO(VFIO_TYPE, VFIO_BASE + 3)
+
+/**
+ * VFIO_GROUP_SET_CONTAINER - _IOW(VFIO_TYPE, VFIO_BASE + 4, __s32)
+ *
+ * Set the container for the VFIO group to the open VFIO file
+ * descriptor provided.  Groups may only belong to a single
+ * container.  Containers may, at their discretion, support multiple
+ * groups.  Only when a container is set are all of the interfaces
+ * of the VFIO file descriptor and the VFIO group file descriptor
+ * available to the user.
+ * Return: 0 on success, -errno on failure.
+ * Availability: Always
+ */
+#define VFIO_GROUP_SET_CONTAINER	_IO(VFIO_TYPE, VFIO_BASE + 4)
+
+/**
+ * VFIO_GROUP_UNSET_CONTAINER - _IO(VFIO_TYPE, VFIO_BASE + 5)
+ *
+ * Remove the group from the attached container.  This is the
+ * opposite of the SET_CONTAINER call and returns the group to
+ * an initial state.  All device file descriptors must be released
+ * prior to calling this interface.  When removing the last group
+ * from a container, the IOMMU will be disabled and all state lost,
+ * effectively also returning the VFIO file descriptor to an initial
+ * state.
+ * Return: 0 on success, -errno on failure.
+ * Availability: When attached to container
+ */
+#define VFIO_GROUP_UNSET_CONTAINER	_IO(VFIO_TYPE, VFIO_BASE + 5)
+
+/**
+ * VFIO_GROUP_GET_DEVICE_FD - _IOW(VFIO_TYPE, VFIO_BASE + 6, char)
+ *
+ * Return a new file descriptor for the device object described by
+ * the provided string.  The string should match a device listed in
+ * the devices subdirectory of the IOMMU group sysfs entry.  The
+ * group containing the device must already be added to this context.
+ * Return: new file descriptor on success, -errno on failure.
+ * Availability: When attached to container
+ */
+#define VFIO_GROUP_GET_DEVICE_FD	_IO(VFIO_TYPE, VFIO_BASE + 6)
+
+/* --------------- IOCTLs for DEVICE file descriptors --------------- */
+
+/**
+ * VFIO_DEVICE_GET_INFO - _IOR(VFIO_TYPE, VFIO_BASE + 7,
+ *						struct vfio_device_info)
+ *
+ * Retrieve information about the device.  Fills in provided
+ * struct vfio_device_info.  Caller sets argsz.
+ * Return: 0 on success, -errno on failure.
+ */
+struct vfio_device_info {
+	__u32	argsz;
+	__u32	flags;
+#define VFIO_DEVICE_FLAGS_RESET	(1 << 0)	/* Device supports reset */
+#define VFIO_DEVICE_FLAGS_PCI	(1 << 1)	/* vfio-pci device */
+#define VFIO_DEVICE_FLAGS_PLATFORM (1 << 2)	/* vfio-platform device */
+#define VFIO_DEVICE_FLAGS_AMBA  (1 << 3)	/* vfio-amba device */
+#define VFIO_DEVICE_FLAGS_CCW	(1 << 4)	/* vfio-ccw device */
+#define VFIO_DEVICE_FLAGS_AP	(1 << 5)	/* vfio-ap device */
+	__u32	num_regions;	/* Max region index + 1 */
+	__u32	num_irqs;	/* Max IRQ index + 1 */
+};
+#define VFIO_DEVICE_GET_INFO		_IO(VFIO_TYPE, VFIO_BASE + 7)
+
+/*
+ * Vendor driver using Mediated device framework should provide device_api
+ * attribute in supported type attribute groups. Device API string should be one
+ * of the following corresponding to device flags in vfio_device_info structure.
+ */
+
+#define VFIO_DEVICE_API_PCI_STRING		"vfio-pci"
+#define VFIO_DEVICE_API_PLATFORM_STRING		"vfio-platform"
+#define VFIO_DEVICE_API_AMBA_STRING		"vfio-amba"
+#define VFIO_DEVICE_API_CCW_STRING		"vfio-ccw"
+#define VFIO_DEVICE_API_AP_STRING		"vfio-ap"
+
+/**
+ * VFIO_DEVICE_GET_REGION_INFO - _IOWR(VFIO_TYPE, VFIO_BASE + 8,
+ *				       struct vfio_region_info)
+ *
+ * Retrieve information about a device region.  Caller provides
+ * struct vfio_region_info with index value set.  Caller sets argsz.
+ * Implementation of region mapping is bus driver specific.  This is
+ * intended to describe MMIO, I/O port, as well as bus specific
+ * regions (ex. PCI config space).  Zero sized regions may be used
+ * to describe unimplemented regions (ex. unimplemented PCI BARs).
+ * Return: 0 on success, -errno on failure.
+ */
+struct vfio_region_info {
+	__u32	argsz;
+	__u32	flags;
+#define VFIO_REGION_INFO_FLAG_READ	(1 << 0) /* Region supports read */
+#define VFIO_REGION_INFO_FLAG_WRITE	(1 << 1) /* Region supports write */
+#define VFIO_REGION_INFO_FLAG_MMAP	(1 << 2) /* Region supports mmap */
+#define VFIO_REGION_INFO_FLAG_CAPS	(1 << 3) /* Info supports caps */
+	__u32	index;		/* Region index */
+	__u32	cap_offset;	/* Offset within info struct of first cap */
+	__u64	size;		/* Region size (bytes) */
+	__u64	offset;		/* Region offset from start of device fd */
+};
+#define VFIO_DEVICE_GET_REGION_INFO	_IO(VFIO_TYPE, VFIO_BASE + 8)
+
+/*
+ * The sparse mmap capability allows finer granularity of specifying areas
+ * within a region with mmap support.  When specified, the user should only
+ * mmap the offset ranges specified by the areas array.  mmaps outside of the
+ * areas specified may fail (such as the range covering a PCI MSI-X table) or
+ * may result in improper device behavior.
+ *
+ * The structures below define version 1 of this capability.
+ */
+#define VFIO_REGION_INFO_CAP_SPARSE_MMAP	1
+
+struct vfio_region_sparse_mmap_area {
+	__u64	offset;	/* Offset of mmap'able area within region */
+	__u64	size;	/* Size of mmap'able area */
+};
+
+struct vfio_region_info_cap_sparse_mmap {
+	struct vfio_info_cap_header header;
+	__u32	nr_areas;
+	__u32	reserved;
+	struct vfio_region_sparse_mmap_area areas[];
+};
+
+/*
+ * The device specific type capability allows regions unique to a specific
+ * device or class of devices to be exposed.  This helps solve the problem for
+ * vfio bus drivers of defining which region indexes correspond to which region
+ * on the device, without needing to resort to static indexes, as done by
+ * vfio-pci.  For instance, if we were to go back in time, we might remove
+ * VFIO_PCI_VGA_REGION_INDEX and let vfio-pci simply define that all indexes
+ * greater than or equal to VFIO_PCI_NUM_REGIONS are device specific and we'd
+ * make a "VGA" device specific type to describe the VGA access space.  This
+ * means that non-VGA devices wouldn't need to waste this index, and thus the
+ * address space associated with it due to implementation of device file
+ * descriptor offsets in vfio-pci.
+ *
+ * The current implementation is now part of the user ABI, so we can't use this
+ * for VGA, but there are other upcoming use cases, such as opregions for Intel
+ * IGD devices and framebuffers for vGPU devices.  We missed VGA, but we'll
+ * use this for future additions.
+ *
+ * The structure below defines version 1 of this capability.
+ */
+#define VFIO_REGION_INFO_CAP_TYPE	2
+
+struct vfio_region_info_cap_type {
+	struct vfio_info_cap_header header;
+	__u32 type;	/* global per bus driver */
+	__u32 subtype;	/* type specific */
+};
+
+/*
+ * List of region types, global per bus driver.
+ * If you introduce a new type, please add it here.
+ */
+
+/* PCI region type containing a PCI vendor part */
+#define VFIO_REGION_TYPE_PCI_VENDOR_TYPE	(1 << 31)
+#define VFIO_REGION_TYPE_PCI_VENDOR_MASK	(0xffff)
+#define VFIO_REGION_TYPE_GFX                    (1)
+#define VFIO_REGION_TYPE_CCW			(2)
+#define VFIO_REGION_TYPE_MIGRATION              (3)
+
+/* sub-types for VFIO_REGION_TYPE_PCI_* */
+
+/* 8086 vendor PCI sub-types */
+#define VFIO_REGION_SUBTYPE_INTEL_IGD_OPREGION	(1)
+#define VFIO_REGION_SUBTYPE_INTEL_IGD_HOST_CFG	(2)
+#define VFIO_REGION_SUBTYPE_INTEL_IGD_LPC_CFG	(3)
+
+/* 10de vendor PCI sub-types */
+/*
+ * NVIDIA GPU NVlink2 RAM is coherent RAM mapped onto the host address space.
+ */
+#define VFIO_REGION_SUBTYPE_NVIDIA_NVLINK2_RAM	(1)
+
+/* 1014 vendor PCI sub-types */
+/*
+ * IBM NPU NVlink2 ATSD (Address Translation Shootdown) register of NPU
+ * to do TLB invalidation on a GPU.
+ */
+#define VFIO_REGION_SUBTYPE_IBM_NVLINK2_ATSD	(1)
+
+/* sub-types for VFIO_REGION_TYPE_GFX */
+#define VFIO_REGION_SUBTYPE_GFX_EDID            (1)
+
+/**
+ * struct vfio_region_gfx_edid - EDID region layout.
+ *
+ * Set display link state and EDID blob.
+ *
+ * The EDID blob has monitor information such as brand, name, serial
+ * number, physical size, supported video modes and more.
+ *
+ * This special region allows userspace (typically qemu) set a virtual
+ * EDID for the virtual monitor, which allows a flexible display
+ * configuration.
+ *
+ * For the edid blob spec look here:
+ *    https://en.wikipedia.org/wiki/Extended_Display_Identification_Data
+ *
+ * On linux systems you can find the EDID blob in sysfs:
+ *    /sys/class/drm/${card}/${connector}/edid
+ *
+ * You can use the edid-decode ulility (comes with xorg-x11-utils) to
+ * decode the EDID blob.
+ *
+ * @edid_offset: location of the edid blob, relative to the
+ *               start of the region (readonly).
+ * @edid_max_size: max size of the edid blob (readonly).
+ * @edid_size: actual edid size (read/write).
+ * @link_state: display link state (read/write).
+ * VFIO_DEVICE_GFX_LINK_STATE_UP: Monitor is turned on.
+ * VFIO_DEVICE_GFX_LINK_STATE_DOWN: Monitor is turned off.
+ * @max_xres: max display width (0 == no limitation, readonly).
+ * @max_yres: max display height (0 == no limitation, readonly).
+ *
+ * EDID update protocol:
+ *   (1) set link-state to down.
+ *   (2) update edid blob and size.
+ *   (3) set link-state to up.
+ */
+struct vfio_region_gfx_edid {
+	__u32 edid_offset;
+	__u32 edid_max_size;
+	__u32 edid_size;
+	__u32 max_xres;
+	__u32 max_yres;
+	__u32 link_state;
+#define VFIO_DEVICE_GFX_LINK_STATE_UP    1
+#define VFIO_DEVICE_GFX_LINK_STATE_DOWN  2
+};
+
+/* sub-types for VFIO_REGION_TYPE_CCW */
+#define VFIO_REGION_SUBTYPE_CCW_ASYNC_CMD	(1)
+#define VFIO_REGION_SUBTYPE_CCW_SCHIB		(2)
+#define VFIO_REGION_SUBTYPE_CCW_CRW		(3)
+
+/* sub-types for VFIO_REGION_TYPE_MIGRATION */
+#define VFIO_REGION_SUBTYPE_MIGRATION           (1)
+
+/*
+ * The structure vfio_device_migration_info is placed at the 0th offset of
+ * the VFIO_REGION_SUBTYPE_MIGRATION region to get and set VFIO device related
+ * migration information. Field accesses from this structure are only supported
+ * at their native width and alignment. Otherwise, the result is undefined and
+ * vendor drivers should return an error.
+ *
+ * device_state: (read/write)
+ *      - The user application writes to this field to inform the vendor driver
+ *        about the device state to be transitioned to.
+ *      - The vendor driver should take the necessary actions to change the
+ *        device state. After successful transition to a given state, the
+ *        vendor driver should return success on write(device_state, state)
+ *        system call. If the device state transition fails, the vendor driver
+ *        should return an appropriate -errno for the fault condition.
+ *      - On the user application side, if the device state transition fails,
+ *	  that is, if write(device_state, state) returns an error, read
+ *	  device_state again to determine the current state of the device from
+ *	  the vendor driver.
+ *      - The vendor driver should return previous state of the device unless
+ *        the vendor driver has encountered an internal error, in which case
+ *        the vendor driver may report the device_state VFIO_DEVICE_STATE_ERROR.
+ *      - The user application must use the device reset ioctl to recover the
+ *        device from VFIO_DEVICE_STATE_ERROR state. If the device is
+ *        indicated to be in a valid device state by reading device_state, the
+ *        user application may attempt to transition the device to any valid
+ *        state reachable from the current state or terminate itself.
+ *
+ *      device_state consists of 3 bits:
+ *      - If bit 0 is set, it indicates the _RUNNING state. If bit 0 is clear,
+ *        it indicates the _STOP state. When the device state is changed to
+ *        _STOP, driver should stop the device before write() returns.
+ *      - If bit 1 is set, it indicates the _SAVING state, which means that the
+ *        driver should start gathering device state information that will be
+ *        provided to the VFIO user application to save the device's state.
+ *      - If bit 2 is set, it indicates the _RESUMING state, which means that
+ *        the driver should prepare to resume the device. Data provided through
+ *        the migration region should be used to resume the device.
+ *      Bits 3 - 31 are reserved for future use. To preserve them, the user
+ *      application should perform a read-modify-write operation on this
+ *      field when modifying the specified bits.
+ *
+ *  +------- _RESUMING
+ *  |+------ _SAVING
+ *  ||+----- _RUNNING
+ *  |||
+ *  000b => Device Stopped, not saving or resuming
+ *  001b => Device running, which is the default state
+ *  010b => Stop the device & save the device state, stop-and-copy state
+ *  011b => Device running and save the device state, pre-copy state
+ *  100b => Device stopped and the device state is resuming
+ *  101b => Invalid state
+ *  110b => Error state
+ *  111b => Invalid state
+ *
+ * State transitions:
+ *
+ *              _RESUMING  _RUNNING    Pre-copy    Stop-and-copy   _STOP
+ *                (100b)     (001b)     (011b)        (010b)       (000b)
+ * 0. Running or default state
+ *                             |
+ *
+ * 1. Normal Shutdown (optional)
+ *                             |------------------------------------->|
+ *
+ * 2. Save the state or suspend
+ *                             |------------------------->|---------->|
+ *
+ * 3. Save the state during live migration
+ *                             |----------->|------------>|---------->|
+ *
+ * 4. Resuming
+ *                  |<---------|
+ *
+ * 5. Resumed
+ *                  |--------->|
+ *
+ * 0. Default state of VFIO device is _RUNNNG when the user application starts.
+ * 1. During normal shutdown of the user application, the user application may
+ *    optionally change the VFIO device state from _RUNNING to _STOP. This
+ *    transition is optional. The vendor driver must support this transition but
+ *    must not require it.
+ * 2. When the user application saves state or suspends the application, the
+ *    device state transitions from _RUNNING to stop-and-copy and then to _STOP.
+ *    On state transition from _RUNNING to stop-and-copy, driver must stop the
+ *    device, save the device state and send it to the application through the
+ *    migration region. The sequence to be followed for such transition is given
+ *    below.
+ * 3. In live migration of user application, the state transitions from _RUNNING
+ *    to pre-copy, to stop-and-copy, and to _STOP.
+ *    On state transition from _RUNNING to pre-copy, the driver should start
+ *    gathering the device state while the application is still running and send
+ *    the device state data to application through the migration region.
+ *    On state transition from pre-copy to stop-and-copy, the driver must stop
+ *    the device, save the device state and send it to the user application
+ *    through the migration region.
+ *    Vendor drivers must support the pre-copy state even for implementations
+ *    where no data is provided to the user before the stop-and-copy state. The
+ *    user must not be required to consume all migration data before the device
+ *    transitions to a new state, including the stop-and-copy state.
+ *    The sequence to be followed for above two transitions is given below.
+ * 4. To start the resuming phase, the device state should be transitioned from
+ *    the _RUNNING to the _RESUMING state.
+ *    In the _RESUMING state, the driver should use the device state data
+ *    received through the migration region to resume the device.
+ * 5. After providing saved device data to the driver, the application should
+ *    change the state from _RESUMING to _RUNNING.
+ *
+ * reserved:
+ *      Reads on this field return zero and writes are ignored.
+ *
+ * pending_bytes: (read only)
+ *      The number of pending bytes still to be migrated from the vendor driver.
+ *
+ * data_offset: (read only)
+ *      The user application should read data_offset field from the migration
+ *      region. The user application should read the device data from this
+ *      offset within the migration region during the _SAVING state or write
+ *      the device data during the _RESUMING state. See below for details of
+ *      sequence to be followed.
+ *
+ * data_size: (read/write)
+ *      The user application should read data_size to get the size in bytes of
+ *      the data copied in the migration region during the _SAVING state and
+ *      write the size in bytes of the data copied in the migration region
+ *      during the _RESUMING state.
+ *
+ * The format of the migration region is as follows:
+ *  ------------------------------------------------------------------
+ * |vfio_device_migration_info|    data section                      |
+ * |                          |     ///////////////////////////////  |
+ * ------------------------------------------------------------------
+ *   ^                              ^
+ *  offset 0-trapped part        data_offset
+ *
+ * The structure vfio_device_migration_info is always followed by the data
+ * section in the region, so data_offset will always be nonzero. The offset
+ * from where the data is copied is decided by the kernel driver. The data
+ * section can be trapped, mmapped, or partitioned, depending on how the kernel
+ * driver defines the data section. The data section partition can be defined
+ * as mapped by the sparse mmap capability. If mmapped, data_offset must be
+ * page aligned, whereas initial section which contains the
+ * vfio_device_migration_info structure, might not end at the offset, which is
+ * page aligned. The user is not required to access through mmap regardless
+ * of the capabilities of the region mmap.
+ * The vendor driver should determine whether and how to partition the data
+ * section. The vendor driver should return data_offset accordingly.
+ *
+ * The sequence to be followed while in pre-copy state and stop-and-copy state
+ * is as follows:
+ * a. Read pending_bytes, indicating the start of a new iteration to get device
+ *    data. Repeated read on pending_bytes at this stage should have no side
+ *    effects.
+ *    If pending_bytes == 0, the user application should not iterate to get data
+ *    for that device.
+ *    If pending_bytes > 0, perform the following steps.
+ * b. Read data_offset, indicating that the vendor driver should make data
+ *    available through the data section. The vendor driver should return this
+ *    read operation only after data is available from (region + data_offset)
+ *    to (region + data_offset + data_size).
+ * c. Read data_size, which is the amount of data in bytes available through
+ *    the migration region.
+ *    Read on data_offset and data_size should return the offset and size of
+ *    the current buffer if the user application reads data_offset and
+ *    data_size more than once here.
+ * d. Read data_size bytes of data from (region + data_offset) from the
+ *    migration region.
+ * e. Process the data.
+ * f. Read pending_bytes, which indicates that the data from the previous
+ *    iteration has been read. If pending_bytes > 0, go to step b.
+ *
+ * The user application can transition from the _SAVING|_RUNNING
+ * (pre-copy state) to the _SAVING (stop-and-copy) state regardless of the
+ * number of pending bytes. The user application should iterate in _SAVING
+ * (stop-and-copy) until pending_bytes is 0.
+ *
+ * The sequence to be followed while _RESUMING device state is as follows:
+ * While data for this device is available, repeat the following steps:
+ * a. Read data_offset from where the user application should write data.
+ * b. Write migration data starting at the migration region + data_offset for
+ *    the length determined by data_size from the migration source.
+ * c. Write data_size, which indicates to the vendor driver that data is
+ *    written in the migration region. Vendor driver must return this write
+ *    operations on consuming data. Vendor driver should apply the
+ *    user-provided migration region data to the device resume state.
+ *
+ * If an error occurs during the above sequences, the vendor driver can return
+ * an error code for next read() or write() operation, which will terminate the
+ * loop. The user application should then take the next necessary action, for
+ * example, failing migration or terminating the user application.
+ *
+ * For the user application, data is opaque. The user application should write
+ * data in the same order as the data is received and the data should be of
+ * same transaction size at the source.
+ */
+
+struct vfio_device_migration_info {
+	__u32 device_state;         /* VFIO device state */
+#define VFIO_DEVICE_STATE_STOP      (0)
+#define VFIO_DEVICE_STATE_RUNNING   (1 << 0)
+#define VFIO_DEVICE_STATE_SAVING    (1 << 1)
+#define VFIO_DEVICE_STATE_RESUMING  (1 << 2)
+#define VFIO_DEVICE_STATE_MASK      (VFIO_DEVICE_STATE_RUNNING | \
+				     VFIO_DEVICE_STATE_SAVING |  \
+				     VFIO_DEVICE_STATE_RESUMING)
+
+#define VFIO_DEVICE_STATE_VALID(state) \
+	(state & VFIO_DEVICE_STATE_RESUMING ? \
+	(state & VFIO_DEVICE_STATE_MASK) == VFIO_DEVICE_STATE_RESUMING : 1)
+
+#define VFIO_DEVICE_STATE_IS_ERROR(state) \
+	((state & VFIO_DEVICE_STATE_MASK) == (VFIO_DEVICE_STATE_SAVING | \
+					      VFIO_DEVICE_STATE_RESUMING))
+
+#define VFIO_DEVICE_STATE_SET_ERROR(state) \
+	((state & ~VFIO_DEVICE_STATE_MASK) | VFIO_DEVICE_SATE_SAVING | \
+					     VFIO_DEVICE_STATE_RESUMING)
+
+	__u32 reserved;
+	__u64 pending_bytes;
+	__u64 data_offset;
+	__u64 data_size;
+};
+
+/*
+ * The MSIX mappable capability informs that MSIX data of a BAR can be mmapped
+ * which allows direct access to non-MSIX registers which happened to be within
+ * the same system page.
+ *
+ * Even though the userspace gets direct access to the MSIX data, the existing
+ * VFIO_DEVICE_SET_IRQS interface must still be used for MSIX configuration.
+ */
+#define VFIO_REGION_INFO_CAP_MSIX_MAPPABLE	3
+
+/*
+ * Capability with compressed real address (aka SSA - small system address)
+ * where GPU RAM is mapped on a system bus. Used by a GPU for DMA routing
+ * and by the userspace to associate a NVLink bridge with a GPU.
+ */
+#define VFIO_REGION_INFO_CAP_NVLINK2_SSATGT	4
+
+struct vfio_region_info_cap_nvlink2_ssatgt {
+	struct vfio_info_cap_header header;
+	__u64 tgt;
+};
+
+/*
+ * Capability with an NVLink link speed. The value is read by
+ * the NVlink2 bridge driver from the bridge's "ibm,nvlink-speed"
+ * property in the device tree. The value is fixed in the hardware
+ * and failing to provide the correct value results in the link
+ * not working with no indication from the driver why.
+ */
+#define VFIO_REGION_INFO_CAP_NVLINK2_LNKSPD	5
+
+struct vfio_region_info_cap_nvlink2_lnkspd {
+	struct vfio_info_cap_header header;
+	__u32 link_speed;
+	__u32 __pad;
+};
+
+/**
+ * VFIO_DEVICE_GET_IRQ_INFO - _IOWR(VFIO_TYPE, VFIO_BASE + 9,
+ *				    struct vfio_irq_info)
+ *
+ * Retrieve information about a device IRQ.  Caller provides
+ * struct vfio_irq_info with index value set.  Caller sets argsz.
+ * Implementation of IRQ mapping is bus driver specific.  Indexes
+ * using multiple IRQs are primarily intended to support MSI-like
+ * interrupt blocks.  Zero count irq blocks may be used to describe
+ * unimplemented interrupt types.
+ *
+ * The EVENTFD flag indicates the interrupt index supports eventfd based
+ * signaling.
+ *
+ * The MASKABLE flags indicates the index supports MASK and UNMASK
+ * actions described below.
+ *
+ * AUTOMASKED indicates that after signaling, the interrupt line is
+ * automatically masked by VFIO and the user needs to unmask the line
+ * to receive new interrupts.  This is primarily intended to distinguish
+ * level triggered interrupts.
+ *
+ * The NORESIZE flag indicates that the interrupt lines within the index
+ * are setup as a set and new subindexes cannot be enabled without first
+ * disabling the entire index.  This is used for interrupts like PCI MSI
+ * and MSI-X where the driver may only use a subset of the available
+ * indexes, but VFIO needs to enable a specific number of vectors
+ * upfront.  In the case of MSI-X, where the user can enable MSI-X and
+ * then add and unmask vectors, it's up to userspace to make the decision
+ * whether to allocate the maximum supported number of vectors or tear
+ * down setup and incrementally increase the vectors as each is enabled.
+ */
+struct vfio_irq_info {
+	__u32	argsz;
+	__u32	flags;
+#define VFIO_IRQ_INFO_EVENTFD		(1 << 0)
+#define VFIO_IRQ_INFO_MASKABLE		(1 << 1)
+#define VFIO_IRQ_INFO_AUTOMASKED	(1 << 2)
+#define VFIO_IRQ_INFO_NORESIZE		(1 << 3)
+	__u32	index;		/* IRQ index */
+	__u32	count;		/* Number of IRQs within this index */
+};
+#define VFIO_DEVICE_GET_IRQ_INFO	_IO(VFIO_TYPE, VFIO_BASE + 9)
+
+/**
+ * VFIO_DEVICE_SET_IRQS - _IOW(VFIO_TYPE, VFIO_BASE + 10, struct vfio_irq_set)
+ *
+ * Set signaling, masking, and unmasking of interrupts.  Caller provides
+ * struct vfio_irq_set with all fields set.  'start' and 'count' indicate
+ * the range of subindexes being specified.
+ *
+ * The DATA flags specify the type of data provided.  If DATA_NONE, the
+ * operation performs the specified action immediately on the specified
+ * interrupt(s).  For example, to unmask AUTOMASKED interrupt [0,0]:
+ * flags = (DATA_NONE|ACTION_UNMASK), index = 0, start = 0, count = 1.
+ *
+ * DATA_BOOL allows sparse support for the same on arrays of interrupts.
+ * For example, to mask interrupts [0,1] and [0,3] (but not [0,2]):
+ * flags = (DATA_BOOL|ACTION_MASK), index = 0, start = 1, count = 3,
+ * data = {1,0,1}
+ *
+ * DATA_EVENTFD binds the specified ACTION to the provided __s32 eventfd.
+ * A value of -1 can be used to either de-assign interrupts if already
+ * assigned or skip un-assigned interrupts.  For example, to set an eventfd
+ * to be trigger for interrupts [0,0] and [0,2]:
+ * flags = (DATA_EVENTFD|ACTION_TRIGGER), index = 0, start = 0, count = 3,
+ * data = {fd1, -1, fd2}
+ * If index [0,1] is previously set, two count = 1 ioctls calls would be
+ * required to set [0,0] and [0,2] without changing [0,1].
+ *
+ * Once a signaling mechanism is set, DATA_BOOL or DATA_NONE can be used
+ * with ACTION_TRIGGER to perform kernel level interrupt loopback testing
+ * from userspace (ie. simulate hardware triggering).
+ *
+ * Setting of an event triggering mechanism to userspace for ACTION_TRIGGER
+ * enables the interrupt index for the device.  Individual subindex interrupts
+ * can be disabled using the -1 value for DATA_EVENTFD or the index can be
+ * disabled as a whole with: flags = (DATA_NONE|ACTION_TRIGGER), count = 0.
+ *
+ * Note that ACTION_[UN]MASK specify user->kernel signaling (irqfds) while
+ * ACTION_TRIGGER specifies kernel->user signaling.
+ */
+struct vfio_irq_set {
+	__u32	argsz;
+	__u32	flags;
+#define VFIO_IRQ_SET_DATA_NONE		(1 << 0) /* Data not present */
+#define VFIO_IRQ_SET_DATA_BOOL		(1 << 1) /* Data is bool (u8) */
+#define VFIO_IRQ_SET_DATA_EVENTFD	(1 << 2) /* Data is eventfd (s32) */
+#define VFIO_IRQ_SET_ACTION_MASK	(1 << 3) /* Mask interrupt */
+#define VFIO_IRQ_SET_ACTION_UNMASK	(1 << 4) /* Unmask interrupt */
+#define VFIO_IRQ_SET_ACTION_TRIGGER	(1 << 5) /* Trigger interrupt */
+	__u32	index;
+	__u32	start;
+	__u32	count;
+	__u8	data[];
+};
+#define VFIO_DEVICE_SET_IRQS		_IO(VFIO_TYPE, VFIO_BASE + 10)
+
+#define VFIO_IRQ_SET_DATA_TYPE_MASK	(VFIO_IRQ_SET_DATA_NONE | \
+					 VFIO_IRQ_SET_DATA_BOOL | \
+					 VFIO_IRQ_SET_DATA_EVENTFD)
+#define VFIO_IRQ_SET_ACTION_TYPE_MASK	(VFIO_IRQ_SET_ACTION_MASK | \
+					 VFIO_IRQ_SET_ACTION_UNMASK | \
+					 VFIO_IRQ_SET_ACTION_TRIGGER)
+/**
+ * VFIO_DEVICE_RESET - _IO(VFIO_TYPE, VFIO_BASE + 11)
+ *
+ * Reset a device.
+ */
+#define VFIO_DEVICE_RESET		_IO(VFIO_TYPE, VFIO_BASE + 11)
+
+/*
+ * The VFIO-PCI bus driver makes use of the following fixed region and
+ * IRQ index mapping.  Unimplemented regions return a size of zero.
+ * Unimplemented IRQ types return a count of zero.
+ */
+
+enum {
+	VFIO_PCI_BAR0_REGION_INDEX,
+	VFIO_PCI_BAR1_REGION_INDEX,
+	VFIO_PCI_BAR2_REGION_INDEX,
+	VFIO_PCI_BAR3_REGION_INDEX,
+	VFIO_PCI_BAR4_REGION_INDEX,
+	VFIO_PCI_BAR5_REGION_INDEX,
+	VFIO_PCI_ROM_REGION_INDEX,
+	VFIO_PCI_CONFIG_REGION_INDEX,
+	/*
+	 * Expose VGA regions defined for PCI base class 03, subclass 00.
+	 * This includes I/O port ranges 0x3b0 to 0x3bb and 0x3c0 to 0x3df
+	 * as well as the MMIO range 0xa0000 to 0xbffff.  Each implemented
+	 * range is found at it's identity mapped offset from the region
+	 * offset, for example 0x3b0 is region_info.offset + 0x3b0.  Areas
+	 * between described ranges are unimplemented.
+	 */
+	VFIO_PCI_VGA_REGION_INDEX,
+	VFIO_PCI_NUM_REGIONS = 9 /* Fixed user ABI, region indexes >=9 use */
+				 /* device specific cap to define content. */
+};
+
+enum {
+	VFIO_PCI_INTX_IRQ_INDEX,
+	VFIO_PCI_MSI_IRQ_INDEX,
+	VFIO_PCI_MSIX_IRQ_INDEX,
+	VFIO_PCI_ERR_IRQ_INDEX,
+	VFIO_PCI_REQ_IRQ_INDEX,
+	VFIO_PCI_NUM_IRQS
+};
+
+/*
+ * The vfio-ccw bus driver makes use of the following fixed region and
+ * IRQ index mapping. Unimplemented regions return a size of zero.
+ * Unimplemented IRQ types return a count of zero.
+ */
+
+enum {
+	VFIO_CCW_CONFIG_REGION_INDEX,
+	VFIO_CCW_NUM_REGIONS
+};
+
+enum {
+	VFIO_CCW_IO_IRQ_INDEX,
+	VFIO_CCW_CRW_IRQ_INDEX,
+	VFIO_CCW_NUM_IRQS
+};
+
+/**
+ * VFIO_DEVICE_GET_PCI_HOT_RESET_INFO - _IORW(VFIO_TYPE, VFIO_BASE + 12,
+ *					      struct vfio_pci_hot_reset_info)
+ *
+ * Return: 0 on success, -errno on failure:
+ *	-enospc = insufficient buffer, -enodev = unsupported for device.
+ */
+struct vfio_pci_dependent_device {
+	__u32	group_id;
+	__u16	segment;
+	__u8	bus;
+	__u8	devfn; /* Use PCI_SLOT/PCI_FUNC */
+};
+
+struct vfio_pci_hot_reset_info {
+	__u32	argsz;
+	__u32	flags;
+	__u32	count;
+	struct vfio_pci_dependent_device	devices[];
+};
+
+#define VFIO_DEVICE_GET_PCI_HOT_RESET_INFO	_IO(VFIO_TYPE, VFIO_BASE + 12)
+
+/**
+ * VFIO_DEVICE_PCI_HOT_RESET - _IOW(VFIO_TYPE, VFIO_BASE + 13,
+ *				    struct vfio_pci_hot_reset)
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+struct vfio_pci_hot_reset {
+	__u32	argsz;
+	__u32	flags;
+	__u32	count;
+	__s32	group_fds[];
+};
+
+#define VFIO_DEVICE_PCI_HOT_RESET	_IO(VFIO_TYPE, VFIO_BASE + 13)
+
+/**
+ * VFIO_DEVICE_QUERY_GFX_PLANE - _IOW(VFIO_TYPE, VFIO_BASE + 14,
+ *                                    struct vfio_device_query_gfx_plane)
+ *
+ * Set the drm_plane_type and flags, then retrieve the gfx plane info.
+ *
+ * flags supported:
+ * - VFIO_GFX_PLANE_TYPE_PROBE and VFIO_GFX_PLANE_TYPE_DMABUF are set
+ *   to ask if the mdev supports dma-buf. 0 on support, -EINVAL on no
+ *   support for dma-buf.
+ * - VFIO_GFX_PLANE_TYPE_PROBE and VFIO_GFX_PLANE_TYPE_REGION are set
+ *   to ask if the mdev supports region. 0 on support, -EINVAL on no
+ *   support for region.
+ * - VFIO_GFX_PLANE_TYPE_DMABUF or VFIO_GFX_PLANE_TYPE_REGION is set
+ *   with each call to query the plane info.
+ * - Others are invalid and return -EINVAL.
+ *
+ * Note:
+ * 1. Plane could be disabled by guest. In that case, success will be
+ *    returned with zero-initialized drm_format, size, width and height
+ *    fields.
+ * 2. x_hot/y_hot is set to 0xFFFFFFFF if no hotspot information available
+ *
+ * Return: 0 on success, -errno on other failure.
+ */
+struct vfio_device_gfx_plane_info {
+	__u32 argsz;
+	__u32 flags;
+#define VFIO_GFX_PLANE_TYPE_PROBE (1 << 0)
+#define VFIO_GFX_PLANE_TYPE_DMABUF (1 << 1)
+#define VFIO_GFX_PLANE_TYPE_REGION (1 << 2)
+	/* in */
+	__u32 drm_plane_type;	/* type of plane: DRM_PLANE_TYPE_* */
+	/* out */
+	__u32 drm_format;	/* drm format of plane */
+	__u64 drm_format_mod;   /* tiled mode */
+	__u32 width;	/* width of plane */
+	__u32 height;	/* height of plane */
+	__u32 stride;	/* stride of plane */
+	__u32 size;	/* size of plane in bytes, align on page*/
+	__u32 x_pos;	/* horizontal position of cursor plane */
+	__u32 y_pos;	/* vertical position of cursor plane*/
+	__u32 x_hot;    /* horizontal position of cursor hotspot */
+	__u32 y_hot;    /* vertical position of cursor hotspot */
+	union {
+		__u32 region_index;	/* region index */
+		__u32 dmabuf_id;	/* dma-buf id */
+	};
+};
+
+#define VFIO_DEVICE_QUERY_GFX_PLANE _IO(VFIO_TYPE, VFIO_BASE + 14)
+
+/**
+ * VFIO_DEVICE_GET_GFX_DMABUF - _IOW(VFIO_TYPE, VFIO_BASE + 15, __u32)
+ *
+ * Return a new dma-buf file descriptor for an exposed guest framebuffer
+ * described by the provided dmabuf_id. The dmabuf_id is returned from VFIO_
+ * DEVICE_QUERY_GFX_PLANE as a token of the exposed guest framebuffer.
+ */
+
+#define VFIO_DEVICE_GET_GFX_DMABUF _IO(VFIO_TYPE, VFIO_BASE + 15)
+
+/**
+ * VFIO_DEVICE_IOEVENTFD - _IOW(VFIO_TYPE, VFIO_BASE + 16,
+ *                              struct vfio_device_ioeventfd)
+ *
+ * Perform a write to the device at the specified device fd offset, with
+ * the specified data and width when the provided eventfd is triggered.
+ * vfio bus drivers may not support this for all regions, for all widths,
+ * or at all.  vfio-pci currently only enables support for BAR regions,
+ * excluding the MSI-X vector table.
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+struct vfio_device_ioeventfd {
+	__u32	argsz;
+	__u32	flags;
+#define VFIO_DEVICE_IOEVENTFD_8		(1 << 0) /* 1-byte write */
+#define VFIO_DEVICE_IOEVENTFD_16	(1 << 1) /* 2-byte write */
+#define VFIO_DEVICE_IOEVENTFD_32	(1 << 2) /* 4-byte write */
+#define VFIO_DEVICE_IOEVENTFD_64	(1 << 3) /* 8-byte write */
+#define VFIO_DEVICE_IOEVENTFD_SIZE_MASK	(0xf)
+	__u64	offset;			/* device fd offset of write */
+	__u64	data;			/* data to be written */
+	__s32	fd;			/* -1 for de-assignment */
+};
+
+#define VFIO_DEVICE_IOEVENTFD		_IO(VFIO_TYPE, VFIO_BASE + 16)
+
+/**
+ * VFIO_DEVICE_FEATURE - _IORW(VFIO_TYPE, VFIO_BASE + 17,
+ *			       struct vfio_device_feature)
+ *
+ * Get, set, or probe feature data of the device.  The feature is selected
+ * using the FEATURE_MASK portion of the flags field.  Support for a feature
+ * can be probed by setting both the FEATURE_MASK and PROBE bits.  A probe
+ * may optionally include the GET and/or SET bits to determine read vs write
+ * access of the feature respectively.  Probing a feature will return success
+ * if the feature is supported and all of the optionally indicated GET/SET
+ * methods are supported.  The format of the data portion of the structure is
+ * specific to the given feature.  The data portion is not required for
+ * probing.  GET and SET are mutually exclusive, except for use with PROBE.
+ *
+ * Return 0 on success, -errno on failure.
+ */
+struct vfio_device_feature {
+	__u32	argsz;
+	__u32	flags;
+#define VFIO_DEVICE_FEATURE_MASK	(0xffff) /* 16-bit feature index */
+#define VFIO_DEVICE_FEATURE_GET		(1 << 16) /* Get feature into data[] */
+#define VFIO_DEVICE_FEATURE_SET		(1 << 17) /* Set feature from data[] */
+#define VFIO_DEVICE_FEATURE_PROBE	(1 << 18) /* Probe feature support */
+	__u8	data[];
+};
+
+#define VFIO_DEVICE_FEATURE		_IO(VFIO_TYPE, VFIO_BASE + 17)
+
+/*
+ * Provide support for setting a PCI VF Token, which is used as a shared
+ * secret between PF and VF drivers.  This feature may only be set on a
+ * PCI SR-IOV PF when SR-IOV is enabled on the PF and there are no existing
+ * open VFs.  Data provided when setting this feature is a 16-byte array
+ * (__u8 b[16]), representing a UUID.
+ */
+#define VFIO_DEVICE_FEATURE_PCI_VF_TOKEN	(0)
+
+/* -------- API for Type1 VFIO IOMMU -------- */
+
+/**
+ * VFIO_IOMMU_GET_INFO - _IOR(VFIO_TYPE, VFIO_BASE + 12, struct vfio_iommu_info)
+ *
+ * Retrieve information about the IOMMU object. Fills in provided
+ * struct vfio_iommu_info. Caller sets argsz.
+ *
+ * XXX Should we do these by CHECK_EXTENSION too?
+ */
+struct vfio_iommu_type1_info {
+	__u32	argsz;
+	__u32	flags;
+#define VFIO_IOMMU_INFO_PGSIZES (1 << 0)	/* supported page sizes info */
+#define VFIO_IOMMU_INFO_CAPS	(1 << 1)	/* Info supports caps */
+	__u64	iova_pgsizes;	/* Bitmap of supported page sizes */
+	__u32   cap_offset;	/* Offset within info struct of first cap */
+};
+
+/*
+ * The IOVA capability allows to report the valid IOVA range(s)
+ * excluding any non-relaxable reserved regions exposed by
+ * devices attached to the container. Any DMA map attempt
+ * outside the valid iova range will return error.
+ *
+ * The structures below define version 1 of this capability.
+ */
+#define VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE  1
+
+struct vfio_iova_range {
+	__u64	start;
+	__u64	end;
+};
+
+struct vfio_iommu_type1_info_cap_iova_range {
+	struct	vfio_info_cap_header header;
+	__u32	nr_iovas;
+	__u32	reserved;
+	struct	vfio_iova_range iova_ranges[];
+};
+
+/*
+ * The migration capability allows to report supported features for migration.
+ *
+ * The structures below define version 1 of this capability.
+ *
+ * The existence of this capability indicates that IOMMU kernel driver supports
+ * dirty page logging.
+ *
+ * pgsize_bitmap: Kernel driver returns bitmap of supported page sizes for dirty
+ * page logging.
+ * max_dirty_bitmap_size: Kernel driver returns maximum supported dirty bitmap
+ * size in bytes that can be used by user applications when getting the dirty
+ * bitmap.
+ */
+#define VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION  2
+
+struct vfio_iommu_type1_info_cap_migration {
+	struct	vfio_info_cap_header header;
+	__u32	flags;
+	__u64	pgsize_bitmap;
+	__u64	max_dirty_bitmap_size;		/* in bytes */
+};
+
+#define VFIO_IOMMU_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 12)
+
+/**
+ * VFIO_IOMMU_MAP_DMA - _IOW(VFIO_TYPE, VFIO_BASE + 13, struct vfio_dma_map)
+ *
+ * Map process virtual addresses to IO virtual addresses using the
+ * provided struct vfio_dma_map. Caller sets argsz. READ &/ WRITE required.
+ */
+struct vfio_iommu_type1_dma_map {
+	__u32	argsz;
+	__u32	flags;
+#define VFIO_DMA_MAP_FLAG_READ (1 << 0)		/* readable from device */
+#define VFIO_DMA_MAP_FLAG_WRITE (1 << 1)	/* writable from device */
+	__u64	vaddr;				/* Process virtual address */
+	__u64	iova;				/* IO virtual address */
+	__u64	size;				/* Size of mapping (bytes) */
+};
+
+#define VFIO_IOMMU_MAP_DMA _IO(VFIO_TYPE, VFIO_BASE + 13)
+
+struct vfio_bitmap {
+	__u64        pgsize;	/* page size for bitmap in bytes */
+	__u64        size;	/* in bytes */
+	__u64		*data;	/* one bit per page */
+};
+
+/**
+ * VFIO_IOMMU_UNMAP_DMA - _IOWR(VFIO_TYPE, VFIO_BASE + 14,
+ *							struct vfio_dma_unmap)
+ *
+ * Unmap IO virtual addresses using the provided struct vfio_dma_unmap.
+ * Caller sets argsz.  The actual unmapped size is returned in the size
+ * field.  No guarantee is made to the user that arbitrary unmaps of iova
+ * or size different from those used in the original mapping call will
+ * succeed.
+ * VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP should be set to get the dirty bitmap
+ * before unmapping IO virtual addresses. When this flag is set, the user must
+ * provide a struct vfio_bitmap in data[]. User must provide zero-allocated
+ * memory via vfio_bitmap.data and its size in the vfio_bitmap.size field.
+ * A bit in the bitmap represents one page, of user provided page size in
+ * vfio_bitmap.pgsize field, consecutively starting from iova offset. Bit set
+ * indicates that the page at that offset from iova is dirty. A Bitmap of the
+ * pages in the range of unmapped size is returned in the user-provided
+ * vfio_bitmap.data.
+ */
+struct vfio_iommu_type1_dma_unmap {
+	__u32	argsz;
+	__u32	flags;
+#define VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP (1 << 0)
+	__u64	iova;				/* IO virtual address */
+	__u64	size;				/* Size of mapping (bytes) */
+	__u8    data[];
+};
+
+#define VFIO_IOMMU_UNMAP_DMA _IO(VFIO_TYPE, VFIO_BASE + 14)
+
+/*
+ * IOCTLs to enable/disable IOMMU container usage.
+ * No parameters are supported.
+ */
+#define VFIO_IOMMU_ENABLE	_IO(VFIO_TYPE, VFIO_BASE + 15)
+#define VFIO_IOMMU_DISABLE	_IO(VFIO_TYPE, VFIO_BASE + 16)
+
+/**
+ * VFIO_IOMMU_DIRTY_PAGES - _IOWR(VFIO_TYPE, VFIO_BASE + 17,
+ *                                     struct vfio_iommu_type1_dirty_bitmap)
+ * IOCTL is used for dirty pages logging.
+ * Caller should set flag depending on which operation to perform, details as
+ * below:
+ *
+ * Calling the IOCTL with VFIO_IOMMU_DIRTY_PAGES_FLAG_START flag set, instructs
+ * the IOMMU driver to log pages that are dirtied or potentially dirtied by
+ * the device; designed to be used when a migration is in progress. Dirty pages
+ * are logged until logging is disabled by user application by calling the IOCTL
+ * with VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP flag.
+ *
+ * Calling the IOCTL with VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP flag set, instructs
+ * the IOMMU driver to stop logging dirtied pages.
+ *
+ * Calling the IOCTL with VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP flag set
+ * returns the dirty pages bitmap for IOMMU container for a given IOVA range.
+ * The user must specify the IOVA range and the pgsize through the structure
+ * vfio_iommu_type1_dirty_bitmap_get in the data[] portion. This interface
+ * supports getting a bitmap of the smallest supported pgsize only and can be
+ * modified in future to get a bitmap of any specified supported pgsize. The
+ * user must provide a zeroed memory area for the bitmap memory and specify its
+ * size in bitmap.size. One bit is used to represent one page consecutively
+ * starting from iova offset. The user should provide page size in bitmap.pgsize
+ * field. A bit set in the bitmap indicates that the page at that offset from
+ * iova is dirty. The caller must set argsz to a value including the size of
+ * structure vfio_iommu_type1_dirty_bitmap_get, but excluding the size of the
+ * actual bitmap. If dirty pages logging is not enabled, an error will be
+ * returned.
+ *
+ * Only one of the flags _START, _STOP and _GET may be specified at a time.
+ *
+ */
+struct vfio_iommu_type1_dirty_bitmap {
+	__u32        argsz;
+	__u32        flags;
+#define VFIO_IOMMU_DIRTY_PAGES_FLAG_START	(1 << 0)
+#define VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP	(1 << 1)
+#define VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP	(1 << 2)
+	__u8         data[];
+};
+
+struct vfio_iommu_type1_dirty_bitmap_get {
+	__u64              iova;	/* IO virtual address */
+	__u64              size;	/* Size of iova range */
+	struct vfio_bitmap bitmap;
+};
+
+#define VFIO_IOMMU_DIRTY_PAGES             _IO(VFIO_TYPE, VFIO_BASE + 17)
+
+/* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */
+
+/*
+ * The SPAPR TCE DDW info struct provides the information about
+ * the details of Dynamic DMA window capability.
+ *
+ * @pgsizes contains a page size bitmask, 4K/64K/16M are supported.
+ * @max_dynamic_windows_supported tells the maximum number of windows
+ * which the platform can create.
+ * @levels tells the maximum number of levels in multi-level IOMMU tables;
+ * this allows splitting a table into smaller chunks which reduces
+ * the amount of physically contiguous memory required for the table.
+ */
+struct vfio_iommu_spapr_tce_ddw_info {
+	__u64 pgsizes;			/* Bitmap of supported page sizes */
+	__u32 max_dynamic_windows_supported;
+	__u32 levels;
+};
+
+/*
+ * The SPAPR TCE info struct provides the information about the PCI bus
+ * address ranges available for DMA, these values are programmed into
+ * the hardware so the guest has to know that information.
+ *
+ * The DMA 32 bit window start is an absolute PCI bus address.
+ * The IOVA address passed via map/unmap ioctls are absolute PCI bus
+ * addresses too so the window works as a filter rather than an offset
+ * for IOVA addresses.
+ *
+ * Flags supported:
+ * - VFIO_IOMMU_SPAPR_INFO_DDW: informs the userspace that dynamic DMA windows
+ *   (DDW) support is present. @ddw is only supported when DDW is present.
+ */
+struct vfio_iommu_spapr_tce_info {
+	__u32 argsz;
+	__u32 flags;
+#define VFIO_IOMMU_SPAPR_INFO_DDW	(1 << 0)	/* DDW supported */
+	__u32 dma32_window_start;	/* 32 bit window start (bytes) */
+	__u32 dma32_window_size;	/* 32 bit window size (bytes) */
+	struct vfio_iommu_spapr_tce_ddw_info ddw;
+};
+
+#define VFIO_IOMMU_SPAPR_TCE_GET_INFO	_IO(VFIO_TYPE, VFIO_BASE + 12)
+
+/*
+ * EEH PE operation struct provides ways to:
+ * - enable/disable EEH functionality;
+ * - unfreeze IO/DMA for frozen PE;
+ * - read PE state;
+ * - reset PE;
+ * - configure PE;
+ * - inject EEH error.
+ */
+struct vfio_eeh_pe_err {
+	__u32 type;
+	__u32 func;
+	__u64 addr;
+	__u64 mask;
+};
+
+struct vfio_eeh_pe_op {
+	__u32 argsz;
+	__u32 flags;
+	__u32 op;
+	union {
+		struct vfio_eeh_pe_err err;
+	};
+};
+
+#define VFIO_EEH_PE_DISABLE		0	/* Disable EEH functionality */
+#define VFIO_EEH_PE_ENABLE		1	/* Enable EEH functionality  */
+#define VFIO_EEH_PE_UNFREEZE_IO		2	/* Enable IO for frozen PE   */
+#define VFIO_EEH_PE_UNFREEZE_DMA	3	/* Enable DMA for frozen PE  */
+#define VFIO_EEH_PE_GET_STATE		4	/* PE state retrieval        */
+#define  VFIO_EEH_PE_STATE_NORMAL	0	/* PE in functional state    */
+#define  VFIO_EEH_PE_STATE_RESET	1	/* PE reset in progress      */
+#define  VFIO_EEH_PE_STATE_STOPPED	2	/* Stopped DMA and IO        */
+#define  VFIO_EEH_PE_STATE_STOPPED_DMA	4	/* Stopped DMA only          */
+#define  VFIO_EEH_PE_STATE_UNAVAIL	5	/* State unavailable         */
+#define VFIO_EEH_PE_RESET_DEACTIVATE	5	/* Deassert PE reset         */
+#define VFIO_EEH_PE_RESET_HOT		6	/* Assert hot reset          */
+#define VFIO_EEH_PE_RESET_FUNDAMENTAL	7	/* Assert fundamental reset  */
+#define VFIO_EEH_PE_CONFIGURE		8	/* PE configuration          */
+#define VFIO_EEH_PE_INJECT_ERR		9	/* Inject EEH error          */
+
+#define VFIO_EEH_PE_OP			_IO(VFIO_TYPE, VFIO_BASE + 21)
+
+/**
+ * VFIO_IOMMU_SPAPR_REGISTER_MEMORY - _IOW(VFIO_TYPE, VFIO_BASE + 17, struct vfio_iommu_spapr_register_memory)
+ *
+ * Registers user space memory where DMA is allowed. It pins
+ * user pages and does the locked memory accounting so
+ * subsequent VFIO_IOMMU_MAP_DMA/VFIO_IOMMU_UNMAP_DMA calls
+ * get faster.
+ */
+struct vfio_iommu_spapr_register_memory {
+	__u32	argsz;
+	__u32	flags;
+	__u64	vaddr;				/* Process virtual address */
+	__u64	size;				/* Size of mapping (bytes) */
+};
+#define VFIO_IOMMU_SPAPR_REGISTER_MEMORY	_IO(VFIO_TYPE, VFIO_BASE + 17)
+
+/**
+ * VFIO_IOMMU_SPAPR_UNREGISTER_MEMORY - _IOW(VFIO_TYPE, VFIO_BASE + 18, struct vfio_iommu_spapr_register_memory)
+ *
+ * Unregisters user space memory registered with
+ * VFIO_IOMMU_SPAPR_REGISTER_MEMORY.
+ * Uses vfio_iommu_spapr_register_memory for parameters.
+ */
+#define VFIO_IOMMU_SPAPR_UNREGISTER_MEMORY	_IO(VFIO_TYPE, VFIO_BASE + 18)
+
+/**
+ * VFIO_IOMMU_SPAPR_TCE_CREATE - _IOWR(VFIO_TYPE, VFIO_BASE + 19, struct vfio_iommu_spapr_tce_create)
+ *
+ * Creates an additional TCE table and programs it (sets a new DMA window)
+ * to every IOMMU group in the container. It receives page shift, window
+ * size and number of levels in the TCE table being created.
+ *
+ * It allocates and returns an offset on a PCI bus of the new DMA window.
+ */
+struct vfio_iommu_spapr_tce_create {
+	__u32 argsz;
+	__u32 flags;
+	/* in */
+	__u32 page_shift;
+	__u32 __resv1;
+	__u64 window_size;
+	__u32 levels;
+	__u32 __resv2;
+	/* out */
+	__u64 start_addr;
+};
+#define VFIO_IOMMU_SPAPR_TCE_CREATE	_IO(VFIO_TYPE, VFIO_BASE + 19)
+
+/**
+ * VFIO_IOMMU_SPAPR_TCE_REMOVE - _IOW(VFIO_TYPE, VFIO_BASE + 20, struct vfio_iommu_spapr_tce_remove)
+ *
+ * Unprograms a TCE table from all groups in the container and destroys it.
+ * It receives a PCI bus offset as a window id.
+ */
+struct vfio_iommu_spapr_tce_remove {
+	__u32 argsz;
+	__u32 flags;
+	/* in */
+	__u64 start_addr;
+};
+#define VFIO_IOMMU_SPAPR_TCE_REMOVE	_IO(VFIO_TYPE, VFIO_BASE + 20)
+
+/* ***************************************************************** */
+
+#endif /* VFIO_H */