[PATCH v2 2/5] vfio: VFIO core header
From: Alex Williamson
Date: Mon Jan 23 2012 - 12:21:31 EST
This defines both the user and bus driver APIs.
Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
---
Documentation/ioctl/ioctl-number.txt | 1
include/linux/vfio.h | 395 ++++++++++++++++++++++++++++++++++
2 files changed, 396 insertions(+), 0 deletions(-)
create mode 100644 include/linux/vfio.h
diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt
index 2550754..79c5ef8 100644
--- a/Documentation/ioctl/ioctl-number.txt
+++ b/Documentation/ioctl/ioctl-number.txt
@@ -88,6 +88,7 @@ Code Seq#(hex) Include File Comments
and kernel/power/user.c
'8' all SNP8023 advanced NIC card
<mailto:mcr@xxxxxxxxxxx>
+';' 64-83 linux/vfio.h
'@' 00-0F linux/radeonfb.h conflict!
'@' 00-0F drivers/video/aty/aty128fb.c conflict!
'A' 00-1F linux/apm_bios.h conflict!
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
new file mode 100644
index 0000000..797dbe4
--- /dev/null
+++ b/include/linux/vfio.h
@@ -0,0 +1,395 @@
+/*
+ * VFIO API definition
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
+ * Author: Alex Williamson <alex.williamson@xxxxxxxxxx>
+ *
+ * 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>
+
+#ifdef __KERNEL__ /* Internal VFIO-core/bus driver API */
+
+/**
+ * struct vfio_device_ops - VFIO bus driver device callbacks
+ *
+ * @match: Return true if buf describes the device
+ * @claim: Force driver to attach to device
+ * @open: Called when userspace receives 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
+ */
+struct vfio_device_ops {
+ bool (*match)(struct device *dev, const char *buf);
+ int (*claim)(struct device *dev);
+ 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);
+};
+
+/**
+ * vfio_group_add_dev() - Add a device to the vfio-core
+ *
+ * @dev: Device to add
+ * @ops: VFIO bus driver callbacks for device
+ *
+ * This registration makes the VFIO core aware of the device, creates
+ * groups objects as required and exposes chardevs under /dev/vfio.
+ *
+ * Return 0 on success, errno on failure.
+ */
+extern int vfio_group_add_dev(struct device *dev,
+ const struct vfio_device_ops *ops);
+
+/**
+ * vfio_group_del_dev() - Remove a device from the vfio-core
+ *
+ * @dev: Device to remove
+ *
+ * Remove a device previously added to the VFIO core, removing groups
+ * and chardevs as necessary.
+ */
+extern void vfio_group_del_dev(struct device *dev);
+
+/**
+ * vfio_bind_dev() - Indicate device is bound to the VFIO bus driver and
+ * register private data structure for ops callbacks.
+ *
+ * @dev: Device being bound
+ * @device_data: VFIO bus driver private data
+ *
+ * This registration indicate that a device previously registered with
+ * vfio_group_add_dev() is now available for use by the VFIO core. When
+ * all devices within a group are available, the group is viable and my
+ * be used by userspace drivers. Typically called from VFIO bus driver
+ * probe function.
+ *
+ * Return 0 on success, errno on failure
+ */
+extern int vfio_bind_dev(struct device *dev, void *device_data);
+
+/**
+ * vfio_unbind_dev() - Indicate device is unbinding from VFIO bus driver
+ *
+ * @dev: Device being unbound
+ *
+ * De-registration of the device previously registered with vfio_bind_dev()
+ * from VFIO. Upon completion, the device is no longer available for use by
+ * the VFIO core. Typically called from the VFIO bus driver remove function.
+ * The VFIO core will attempt to release the device from users and may take
+ * measures to free the device and/or block as necessary.
+ *
+ * Returns pointer to private device_data structure registered with
+ * vfio_bind_dev().
+ */
+extern void *vfio_unbind_dev(struct device *dev);
+
+
+/**
+ * offsetofend(TYPE, MEMBER)
+ *
+ * @TYPE: The type of the structure
+ * @MEMBER: The member within the structure to get the end offset of
+ *
+ * Simple helper macro for dealing with variable sized structures passed
+ * from user space. This allows us to easily determine if the provided
+ * structure is sized to include various fields.
+ */
+#define offsetofend(TYPE, MEMBER) ({ \
+ TYPE tmp; \
+ offsetof(TYPE, MEMBER) + sizeof(tmp.MEMBER); }) \
+
+#endif /* __KERNEL__ */
+
+/* Kernel & User level defines for VFIO IOCTLs. */
+
+/*
+ * 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
+
+/* --------------- IOCTLs for GROUP file descriptors --------------- */
+
+/**
+ * VFIO_GROUP_GET_INFO - _IOR(VFIO_TYPE, VFIO_BASE + 0, struct vfio_group_info)
+ *
+ * Retrieve information about the group. Fills in provided
+ * struct vfio_group_info. Caller sets argsz.
+ */
+struct vfio_group_info {
+ __u32 argsz;
+ __u32 flags;
+#define VFIO_GROUP_FLAGS_VIABLE (1 << 0)
+#define VFIO_GROUP_FLAGS_MM_LOCKED (1 << 1)
+};
+
+#define VFIO_GROUP_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 0)
+
+/**
+ * VFIO_GROUP_MERGE - _IOW(VFIO_TYPE, VFIO_BASE + 1, __s32)
+ *
+ * Merge group indicated by passed file descriptor into current group.
+ * Current group may be in use, group indicated by file descriptor
+ * cannot be in use (no open iommu or devices).
+ */
+#define VFIO_GROUP_MERGE _IOW(VFIO_TYPE, VFIO_BASE + 1, __s32)
+
+/**
+ * VFIO_GROUP_UNMERGE - _IO(VFIO_TYPE, VFIO_BASE + 2)
+ *
+ * Remove the current group from a merged set. The current group cannot
+ * have any open devices.
+ */
+#define VFIO_GROUP_UNMERGE _IO(VFIO_TYPE, VFIO_BASE + 2)
+
+/**
+ * VFIO_GROUP_GET_IOMMU_FD - _IO(VFIO_TYPE, VFIO_BASE + 3)
+ *
+ * Return a new file descriptor for the IOMMU object. The IOMMU object
+ * is shared among members of a merged group.
+ */
+#define VFIO_GROUP_GET_IOMMU_FD _IO(VFIO_TYPE, VFIO_BASE + 3)
+
+/**
+ * VFIO_GROUP_GET_DEVICE_FD - _IOW(VFIO_TYPE, VFIO_BASE + 4, char)
+ *
+ * Return a new file descriptor for the device object described by
+ * the provided char array.
+ */
+#define VFIO_GROUP_GET_DEVICE_FD _IOW(VFIO_TYPE, VFIO_BASE + 4, char)
+
+
+/* --------------- IOCTLs for IOMMU file descriptors --------------- */
+
+/**
+ * VFIO_IOMMU_GET_INFO - _IOR(VFIO_TYPE, VFIO_BASE + 5, struct vfio_iommu_info)
+ *
+ * Retrieve information about the IOMMU object. Fills in provided
+ * struct vfio_iommu_info. Caller sets argsz.
+ */
+struct vfio_iommu_info {
+ __u32 argsz;
+ __u32 flags;
+ __u64 iova_start; /* IOVA base address */
+ __u64 iova_size; /* IOVA window size */
+ __u64 iova_entries; /* Number mapping entries available */
+ __u64 iova_pgsizes; /* Bitmap of supported page sizes */
+};
+
+#define VFIO_IOMMU_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 5)
+
+/**
+ * VFIO_IOMMU_MAP_DMA - _IOW(VFIO_TYPE, VFIO_BASE + 6, 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_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 + 6)
+
+/**
+ * VFIO_IOMMU_UNMAP_DMA - _IOW(VFIO_TYPE, VFIO_BASE + 7, struct vfio_dma_unmap)
+ *
+ * Unmap IO virtual addresses using the provided struct vfio_dma_unmap.
+ * Caller sets argsz.
+ */
+struct vfio_dma_unmap {
+ __u32 argsz;
+ __u32 flags;
+ __u64 iova; /* IO virtual address */
+ __u64 size; /* Size of mapping (bytes) */
+};
+
+#define VFIO_IOMMU_UNMAP_DMA _IO(VFIO_TYPE, VFIO_BASE + 7)
+
+
+/* --------------- IOCTLs for DEVICE file descriptors --------------- */
+
+/**
+ * VFIO_DEVICE_GET_INFO - _IOR(VFIO_TYPE, VFIO_BASE + 8,
+ * struct vfio_device_info)
+ *
+ * Retrieve information about the device. Fills in provided
+ * struct vfio_device_info. Caller sets argsz.
+ */
+struct vfio_device_info {
+ __u32 argsz;
+ __u32 flags;
+#define VFIO_DEVICE_FLAGS_RESET (1 << 0) /* Device supports reset */
+ __u32 num_regions; /* Max region index + 1 */
+ __u32 num_irqs; /* Max IRQ index + 1 */
+};
+
+#define VFIO_DEVICE_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 8)
+
+/**
+ * VFIO_DEVICE_GET_REGION_INFO - _IOWR(VFIO_TYPE, VFIO_BASE + 9,
+ * 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).
+ */
+struct vfio_region_info {
+ __u32 argsz;
+ __u32 flags;
+#define VFIO_REGION_INFO_FLAG_MMAP (1 << 0) /* Region supports mmap */
+#define VFIO_REGION_INFO_FLAG_RO (1 << 1) /* Region is read-only */
+ __u32 index; /* Region index */
+ __u32 resv; /* Reserved for alignment */
+ __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 + 9)
+
+/**
+ * VFIO_DEVICE_GET_IRQ_INFO - _IOWR(VFIO_TYPE, VFIO_BASE + 10,
+ * 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 */
+ __s32 count; /* Number of IRQs within this index */
+};
+
+#define VFIO_DEVICE_GET_IRQ_INFO _IO(VFIO_TYPE, VFIO_BASE + 10)
+
+/**
+ * VFIO_DEVICE_SET_IRQS - _IOW(VFIO_TYPE, VFIO_BASE + 11, 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;
+ __s32 start;
+ __s32 count;
+ __u8 data[];
+};
+
+#define VFIO_DEVICE_SET_IRQS _IO(VFIO_TYPE, VFIO_BASE + 11)
+
+#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 + 12)
+ *
+ * Reset a device.
+ */
+#define VFIO_DEVICE_RESET _IO(VFIO_TYPE, VFIO_BASE + 12)
+
+#endif /* VFIO_H */
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/