aboutsummaryrefslogtreecommitdiff
path: root/include/linux/vfio.h
blob: e05ddc6fe6a55607d1ac65a2a0949ad45c078230 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * VFIO API definition
 *
 * Copyright (C) 2012 Red Hat, Inc.  All rights reserved.
 *     Author: Alex Williamson <alex.williamson@redhat.com>
 */
#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 kvm;

/*
 * VFIO devices can be placed in a set, this allows all devices to share this
 * structure and the VFIO core will provide a lock that is held around
 * open_device()/close_device() for all devices in the set.
 */
struct vfio_device_set {
	void *set_id;
	struct mutex lock;
	struct list_head device_list;
	unsigned int device_count;
};

struct vfio_device {
	struct device *dev;
	const struct vfio_device_ops *ops;
	/*
	 * mig_ops is a static property of the vfio_device which must be set
	 * prior to registering the vfio_device.
	 */
	const struct vfio_migration_ops *mig_ops;
	struct vfio_group *group;
	struct vfio_device_set *dev_set;
	struct list_head dev_set_list;
	unsigned int migration_flags;
	/* Driver must reference the kvm during open_device or never touch it */
	struct kvm *kvm;

	/* Members below here are private, not for driver use */
	refcount_t refcount;
	unsigned int open_count;
	struct completion comp;
	struct list_head group_next;
	struct list_head iommu_entry;
};

/**
 * struct vfio_device_ops - VFIO bus driver device callbacks
 *
 * @open_device: Called when the first file descriptor is opened for this device
 * @close_device: Opposite of open_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
 * @match: Optional device name match callback (return: 0 for no-match, >0 for
 *         match, -errno for abort (ex. match with insufficient or incorrect
 *         additional args)
 * @dma_unmap: Called when userspace unmaps IOVA from the container
 *             this device is attached to.
 * @device_feature: Optional, fill in the VFIO_DEVICE_FEATURE ioctl
 */
struct vfio_device_ops {
	char	*name;
	int	(*open_device)(struct vfio_device *vdev);
	void	(*close_device)(struct vfio_device *vdev);
	ssize_t	(*read)(struct vfio_device *vdev, char __user *buf,
			size_t count, loff_t *ppos);
	ssize_t	(*write)(struct vfio_device *vdev, const char __user *buf,
			 size_t count, loff_t *size);
	long	(*ioctl)(struct vfio_device *vdev, unsigned int cmd,
			 unsigned long arg);
	int	(*mmap)(struct vfio_device *vdev, struct vm_area_struct *vma);
	void	(*request)(struct vfio_device *vdev, unsigned int count);
	int	(*match)(struct vfio_device *vdev, char *buf);
	void	(*dma_unmap)(struct vfio_device *vdev, u64 iova, u64 length);
	int	(*device_feature)(struct vfio_device *device, u32 flags,
				  void __user *arg, size_t argsz);
};

/**
 * @migration_set_state: Optional callback to change the migration state for
 *         devices that support migration. It's mandatory for
 *         VFIO_DEVICE_FEATURE_MIGRATION migration support.
 *         The returned FD is used for data transfer according to the FSM
 *         definition. The driver is responsible to ensure that FD reaches end
 *         of stream or error whenever the migration FSM leaves a data transfer
 *         state or before close_device() returns.
 * @migration_get_state: Optional callback to get the migration state for
 *         devices that support migration. It's mandatory for
 *         VFIO_DEVICE_FEATURE_MIGRATION migration support.
 */
struct vfio_migration_ops {
	struct file *(*migration_set_state)(
		struct vfio_device *device,
		enum vfio_device_mig_state new_state);
	int (*migration_get_state)(struct vfio_device *device,
				   enum vfio_device_mig_state *curr_state);
};

/**
 * vfio_check_feature - Validate user input for the VFIO_DEVICE_FEATURE ioctl
 * @flags: Arg from the device_feature op
 * @argsz: Arg from the device_feature op
 * @supported_ops: Combination of VFIO_DEVICE_FEATURE_GET and SET the driver
 *                 supports
 * @minsz: Minimum data size the driver accepts
 *
 * For use in a driver's device_feature op. Checks that the inputs to the
 * VFIO_DEVICE_FEATURE ioctl are correct for the driver's feature. Returns 1 if
 * the driver should execute the get or set, otherwise the relevant
 * value should be returned.
 */
static inline int vfio_check_feature(u32 flags, size_t argsz, u32 supported_ops,
				    size_t minsz)
{
	if ((flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET)) &
	    ~supported_ops)
		return -EINVAL;
	if (flags & VFIO_DEVICE_FEATURE_PROBE)
		return 0;
	/* Without PROBE one of GET or SET must be requested */
	if (!(flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET)))
		return -EINVAL;
	if (argsz < minsz)
		return -EINVAL;
	return 1;
}

void vfio_init_group_dev(struct vfio_device *device, struct device *dev,
			 const struct vfio_device_ops *ops);
void vfio_uninit_group_dev(struct vfio_device *device);
int vfio_register_group_dev(struct vfio_device *device);
int vfio_register_emulated_iommu_dev(struct vfio_device *device);
void vfio_unregister_group_dev(struct vfio_device *device);

int vfio_assign_device_set(struct vfio_device *device, void *set_id);

int vfio_mig_get_next_state(struct vfio_device *device,
			    enum vfio_device_mig_state cur_fsm,
			    enum vfio_device_mig_state new_fsm,
			    enum vfio_device_mig_state *next_fsm);

/*
 * External user API
 */
struct iommu_group *vfio_file_iommu_group(struct file *file);
bool vfio_file_enforced_coherent(struct file *file);
void vfio_file_set_kvm(struct file *file, struct kvm *kvm);
bool vfio_file_has_dev(struct file *file, struct vfio_device *device);

#define VFIO_PIN_PAGES_MAX_ENTRIES	(PAGE_SIZE/sizeof(unsigned long))

int vfio_pin_pages(struct vfio_device *device, dma_addr_t iova,
		   int npage, int prot, struct page **pages);
void vfio_unpin_pages(struct vfio_device *device, dma_addr_t iova, int npage);
int vfio_dma_rw(struct vfio_device *device, dma_addr_t iova,
		void *data, size_t len, bool write);

/*
 * Sub-module helpers
 */
struct vfio_info_cap {
	struct vfio_info_cap_header *buf;
	size_t size;
};
struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps,
					       size_t size, u16 id,
					       u16 version);
void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset);

int vfio_info_add_capability(struct vfio_info_cap *caps,
			     struct vfio_info_cap_header *cap, size_t size);

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)
void vfio_spapr_pci_eeh_open(struct pci_dev *pdev);
void vfio_spapr_pci_eeh_release(struct pci_dev *pdev);
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;
};

int vfio_virqfd_enable(void *opaque, int (*handler)(void *, void *),
		       void (*thread)(void *, void *), void *data,
		       struct virqfd **pvirqfd, int fd);
void vfio_virqfd_disable(struct virqfd **pvirqfd);

#endif /* VFIO_H */