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