1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * VFIO API definition
4 *
5 * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
6 * Author: Alex Williamson <alex.williamson@redhat.com>
7 */
8 #ifndef VFIO_H
9 #define VFIO_H
10
11
12 #include <linux/iommu.h>
13 #include <linux/mm.h>
14 #include <linux/workqueue.h>
15 #include <linux/poll.h>
16 #include <uapi/linux/vfio.h>
17
18 struct kvm;
19
20 /*
21 * VFIO devices can be placed in a set, this allows all devices to share this
22 * structure and the VFIO core will provide a lock that is held around
23 * open_device()/close_device() for all devices in the set.
24 */
25 struct vfio_device_set {
26 void *set_id;
27 struct mutex lock;
28 struct list_head device_list;
29 unsigned int device_count;
30 };
31
32 struct vfio_device {
33 struct device *dev;
34 const struct vfio_device_ops *ops;
35 /*
36 * mig_ops is a static property of the vfio_device which must be set
37 * prior to registering the vfio_device.
38 */
39 const struct vfio_migration_ops *mig_ops;
40 struct vfio_group *group;
41 struct vfio_device_set *dev_set;
42 struct list_head dev_set_list;
43 unsigned int migration_flags;
44 /* Driver must reference the kvm during open_device or never touch it */
45 struct kvm *kvm;
46
47 /* Members below here are private, not for driver use */
48 refcount_t refcount;
49 unsigned int open_count;
50 struct completion comp;
51 struct list_head group_next;
52 };
53
54 /**
55 * struct vfio_device_ops - VFIO bus driver device callbacks
56 *
57 * @open_device: Called when the first file descriptor is opened for this device
58 * @close_device: Opposite of open_device
59 * @read: Perform read(2) on device file descriptor
60 * @write: Perform write(2) on device file descriptor
61 * @ioctl: Perform ioctl(2) on device file descriptor, supporting VFIO_DEVICE_*
62 * operations documented below
63 * @mmap: Perform mmap(2) on a region of the device file descriptor
64 * @request: Request for the bus driver to release the device
65 * @match: Optional device name match callback (return: 0 for no-match, >0 for
66 * match, -errno for abort (ex. match with insufficient or incorrect
67 * additional args)
68 * @device_feature: Optional, fill in the VFIO_DEVICE_FEATURE ioctl
69 */
70 struct vfio_device_ops {
71 char *name;
72 int (*open_device)(struct vfio_device *vdev);
73 void (*close_device)(struct vfio_device *vdev);
74 ssize_t (*read)(struct vfio_device *vdev, char __user *buf,
75 size_t count, loff_t *ppos);
76 ssize_t (*write)(struct vfio_device *vdev, const char __user *buf,
77 size_t count, loff_t *size);
78 long (*ioctl)(struct vfio_device *vdev, unsigned int cmd,
79 unsigned long arg);
80 int (*mmap)(struct vfio_device *vdev, struct vm_area_struct *vma);
81 void (*request)(struct vfio_device *vdev, unsigned int count);
82 int (*match)(struct vfio_device *vdev, char *buf);
83 int (*device_feature)(struct vfio_device *device, u32 flags,
84 void __user *arg, size_t argsz);
85 };
86
87 /**
88 * @migration_set_state: Optional callback to change the migration state for
89 * devices that support migration. It's mandatory for
90 * VFIO_DEVICE_FEATURE_MIGRATION migration support.
91 * The returned FD is used for data transfer according to the FSM
92 * definition. The driver is responsible to ensure that FD reaches end
93 * of stream or error whenever the migration FSM leaves a data transfer
94 * state or before close_device() returns.
95 * @migration_get_state: Optional callback to get the migration state for
96 * devices that support migration. It's mandatory for
97 * VFIO_DEVICE_FEATURE_MIGRATION migration support.
98 */
99 struct vfio_migration_ops {
100 struct file *(*migration_set_state)(
101 struct vfio_device *device,
102 enum vfio_device_mig_state new_state);
103 int (*migration_get_state)(struct vfio_device *device,
104 enum vfio_device_mig_state *curr_state);
105 };
106
107 /**
108 * vfio_check_feature - Validate user input for the VFIO_DEVICE_FEATURE ioctl
109 * @flags: Arg from the device_feature op
110 * @argsz: Arg from the device_feature op
111 * @supported_ops: Combination of VFIO_DEVICE_FEATURE_GET and SET the driver
112 * supports
113 * @minsz: Minimum data size the driver accepts
114 *
115 * For use in a driver's device_feature op. Checks that the inputs to the
116 * VFIO_DEVICE_FEATURE ioctl are correct for the driver's feature. Returns 1 if
117 * the driver should execute the get or set, otherwise the relevant
118 * value should be returned.
119 */
vfio_check_feature(u32 flags,size_t argsz,u32 supported_ops,size_t minsz)120 static inline int vfio_check_feature(u32 flags, size_t argsz, u32 supported_ops,
121 size_t minsz)
122 {
123 if ((flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET)) &
124 ~supported_ops)
125 return -EINVAL;
126 if (flags & VFIO_DEVICE_FEATURE_PROBE)
127 return 0;
128 /* Without PROBE one of GET or SET must be requested */
129 if (!(flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET)))
130 return -EINVAL;
131 if (argsz < minsz)
132 return -EINVAL;
133 return 1;
134 }
135
136 void vfio_init_group_dev(struct vfio_device *device, struct device *dev,
137 const struct vfio_device_ops *ops);
138 void vfio_uninit_group_dev(struct vfio_device *device);
139 int vfio_register_group_dev(struct vfio_device *device);
140 int vfio_register_emulated_iommu_dev(struct vfio_device *device);
141 void vfio_unregister_group_dev(struct vfio_device *device);
142
143 int vfio_assign_device_set(struct vfio_device *device, void *set_id);
144
145 int vfio_mig_get_next_state(struct vfio_device *device,
146 enum vfio_device_mig_state cur_fsm,
147 enum vfio_device_mig_state new_fsm,
148 enum vfio_device_mig_state *next_fsm);
149
150 /*
151 * External user API
152 */
153 extern struct iommu_group *vfio_file_iommu_group(struct file *file);
154 extern bool vfio_file_enforced_coherent(struct file *file);
155 extern void vfio_file_set_kvm(struct file *file, struct kvm *kvm);
156 extern bool vfio_file_has_dev(struct file *file, struct vfio_device *device);
157
158 #define VFIO_PIN_PAGES_MAX_ENTRIES (PAGE_SIZE/sizeof(unsigned long))
159
160 extern int vfio_pin_pages(struct vfio_device *device, unsigned long *user_pfn,
161 int npage, int prot, unsigned long *phys_pfn);
162 extern int vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn,
163 int npage);
164 extern int vfio_dma_rw(struct vfio_device *device, dma_addr_t user_iova,
165 void *data, size_t len, bool write);
166
167 /* each type has independent events */
168 enum vfio_notify_type {
169 VFIO_IOMMU_NOTIFY = 0,
170 };
171
172 /* events for VFIO_IOMMU_NOTIFY */
173 #define VFIO_IOMMU_NOTIFY_DMA_UNMAP BIT(0)
174
175 extern int vfio_register_notifier(struct vfio_device *device,
176 enum vfio_notify_type type,
177 unsigned long *required_events,
178 struct notifier_block *nb);
179 extern int vfio_unregister_notifier(struct vfio_device *device,
180 enum vfio_notify_type type,
181 struct notifier_block *nb);
182
183
184 /*
185 * Sub-module helpers
186 */
187 struct vfio_info_cap {
188 struct vfio_info_cap_header *buf;
189 size_t size;
190 };
191 extern struct vfio_info_cap_header *vfio_info_cap_add(
192 struct vfio_info_cap *caps, size_t size, u16 id, u16 version);
193 extern void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset);
194
195 extern int vfio_info_add_capability(struct vfio_info_cap *caps,
196 struct vfio_info_cap_header *cap,
197 size_t size);
198
199 extern int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr,
200 int num_irqs, int max_irq_type,
201 size_t *data_size);
202
203 struct pci_dev;
204 #if IS_ENABLED(CONFIG_VFIO_SPAPR_EEH)
205 extern void vfio_spapr_pci_eeh_open(struct pci_dev *pdev);
206 extern void vfio_spapr_pci_eeh_release(struct pci_dev *pdev);
207 extern long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
208 unsigned int cmd,
209 unsigned long arg);
210 #else
vfio_spapr_pci_eeh_open(struct pci_dev * pdev)211 static inline void vfio_spapr_pci_eeh_open(struct pci_dev *pdev)
212 {
213 }
214
vfio_spapr_pci_eeh_release(struct pci_dev * pdev)215 static inline void vfio_spapr_pci_eeh_release(struct pci_dev *pdev)
216 {
217 }
218
vfio_spapr_iommu_eeh_ioctl(struct iommu_group * group,unsigned int cmd,unsigned long arg)219 static inline long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
220 unsigned int cmd,
221 unsigned long arg)
222 {
223 return -ENOTTY;
224 }
225 #endif /* CONFIG_VFIO_SPAPR_EEH */
226
227 /*
228 * IRQfd - generic
229 */
230 struct virqfd {
231 void *opaque;
232 struct eventfd_ctx *eventfd;
233 int (*handler)(void *, void *);
234 void (*thread)(void *, void *);
235 void *data;
236 struct work_struct inject;
237 wait_queue_entry_t wait;
238 poll_table pt;
239 struct work_struct shutdown;
240 struct virqfd **pvirqfd;
241 };
242
243 extern int vfio_virqfd_enable(void *opaque,
244 int (*handler)(void *, void *),
245 void (*thread)(void *, void *),
246 void *data, struct virqfd **pvirqfd, int fd);
247 extern void vfio_virqfd_disable(struct virqfd **pvirqfd);
248
249 #endif /* VFIO_H */
250