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 #include <linux/iova_bitmap.h> 18 19 struct kvm; 20 struct iommufd_ctx; 21 struct iommufd_device; 22 struct iommufd_access; 23 24 /* 25 * VFIO devices can be placed in a set, this allows all devices to share this 26 * structure and the VFIO core will provide a lock that is held around 27 * open_device()/close_device() for all devices in the set. 28 */ 29 struct vfio_device_set { 30 void *set_id; 31 struct mutex lock; 32 struct list_head device_list; 33 unsigned int device_count; 34 }; 35 36 struct vfio_device { 37 struct device *dev; 38 const struct vfio_device_ops *ops; 39 /* 40 * mig_ops/log_ops is a static property of the vfio_device which must 41 * be set prior to registering the vfio_device. 42 */ 43 const struct vfio_migration_ops *mig_ops; 44 const struct vfio_log_ops *log_ops; 45 struct vfio_group *group; 46 struct vfio_device_set *dev_set; 47 struct list_head dev_set_list; 48 unsigned int migration_flags; 49 struct kvm *kvm; 50 51 /* Members below here are private, not for driver use */ 52 unsigned int index; 53 struct device device; /* device.kref covers object life circle */ 54 refcount_t refcount; /* user count on registered device*/ 55 unsigned int open_count; 56 struct completion comp; 57 struct list_head group_next; 58 struct list_head iommu_entry; 59 struct iommufd_access *iommufd_access; 60 void (*put_kvm)(struct kvm *kvm); 61 #if IS_ENABLED(CONFIG_IOMMUFD) 62 struct iommufd_device *iommufd_device; 63 bool iommufd_attached; 64 #endif 65 }; 66 67 /** 68 * struct vfio_device_ops - VFIO bus driver device callbacks 69 * 70 * @init: initialize private fields in device structure 71 * @release: Reclaim private fields in device structure 72 * @bind_iommufd: Called when binding the device to an iommufd 73 * @unbind_iommufd: Opposite of bind_iommufd 74 * @attach_ioas: Called when attaching device to an IOAS/HWPT managed by the 75 * bound iommufd. Undo in unbind_iommufd. 76 * @open_device: Called when the first file descriptor is opened for this device 77 * @close_device: Opposite of open_device 78 * @read: Perform read(2) on device file descriptor 79 * @write: Perform write(2) on device file descriptor 80 * @ioctl: Perform ioctl(2) on device file descriptor, supporting VFIO_DEVICE_* 81 * operations documented below 82 * @mmap: Perform mmap(2) on a region of the device file descriptor 83 * @request: Request for the bus driver to release the device 84 * @match: Optional device name match callback (return: 0 for no-match, >0 for 85 * match, -errno for abort (ex. match with insufficient or incorrect 86 * additional args) 87 * @dma_unmap: Called when userspace unmaps IOVA from the container 88 * this device is attached to. 89 * @device_feature: Optional, fill in the VFIO_DEVICE_FEATURE ioctl 90 */ 91 struct vfio_device_ops { 92 char *name; 93 int (*init)(struct vfio_device *vdev); 94 void (*release)(struct vfio_device *vdev); 95 int (*bind_iommufd)(struct vfio_device *vdev, 96 struct iommufd_ctx *ictx, u32 *out_device_id); 97 void (*unbind_iommufd)(struct vfio_device *vdev); 98 int (*attach_ioas)(struct vfio_device *vdev, u32 *pt_id); 99 int (*open_device)(struct vfio_device *vdev); 100 void (*close_device)(struct vfio_device *vdev); 101 ssize_t (*read)(struct vfio_device *vdev, char __user *buf, 102 size_t count, loff_t *ppos); 103 ssize_t (*write)(struct vfio_device *vdev, const char __user *buf, 104 size_t count, loff_t *size); 105 long (*ioctl)(struct vfio_device *vdev, unsigned int cmd, 106 unsigned long arg); 107 int (*mmap)(struct vfio_device *vdev, struct vm_area_struct *vma); 108 void (*request)(struct vfio_device *vdev, unsigned int count); 109 int (*match)(struct vfio_device *vdev, char *buf); 110 void (*dma_unmap)(struct vfio_device *vdev, u64 iova, u64 length); 111 int (*device_feature)(struct vfio_device *device, u32 flags, 112 void __user *arg, size_t argsz); 113 }; 114 115 #if IS_ENABLED(CONFIG_IOMMUFD) 116 int vfio_iommufd_physical_bind(struct vfio_device *vdev, 117 struct iommufd_ctx *ictx, u32 *out_device_id); 118 void vfio_iommufd_physical_unbind(struct vfio_device *vdev); 119 int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id); 120 int vfio_iommufd_emulated_bind(struct vfio_device *vdev, 121 struct iommufd_ctx *ictx, u32 *out_device_id); 122 void vfio_iommufd_emulated_unbind(struct vfio_device *vdev); 123 int vfio_iommufd_emulated_attach_ioas(struct vfio_device *vdev, u32 *pt_id); 124 #else 125 #define vfio_iommufd_physical_bind \ 126 ((int (*)(struct vfio_device *vdev, struct iommufd_ctx *ictx, \ 127 u32 *out_device_id)) NULL) 128 #define vfio_iommufd_physical_unbind \ 129 ((void (*)(struct vfio_device *vdev)) NULL) 130 #define vfio_iommufd_physical_attach_ioas \ 131 ((int (*)(struct vfio_device *vdev, u32 *pt_id)) NULL) 132 #define vfio_iommufd_emulated_bind \ 133 ((int (*)(struct vfio_device *vdev, struct iommufd_ctx *ictx, \ 134 u32 *out_device_id)) NULL) 135 #define vfio_iommufd_emulated_unbind \ 136 ((void (*)(struct vfio_device *vdev)) NULL) 137 #define vfio_iommufd_emulated_attach_ioas \ 138 ((int (*)(struct vfio_device *vdev, u32 *pt_id)) NULL) 139 #endif 140 141 /** 142 * @migration_set_state: Optional callback to change the migration state for 143 * devices that support migration. It's mandatory for 144 * VFIO_DEVICE_FEATURE_MIGRATION migration support. 145 * The returned FD is used for data transfer according to the FSM 146 * definition. The driver is responsible to ensure that FD reaches end 147 * of stream or error whenever the migration FSM leaves a data transfer 148 * state or before close_device() returns. 149 * @migration_get_state: Optional callback to get the migration state for 150 * devices that support migration. It's mandatory for 151 * VFIO_DEVICE_FEATURE_MIGRATION migration support. 152 * @migration_get_data_size: Optional callback to get the estimated data 153 * length that will be required to complete stop copy. It's mandatory for 154 * VFIO_DEVICE_FEATURE_MIGRATION migration support. 155 */ 156 struct vfio_migration_ops { 157 struct file *(*migration_set_state)( 158 struct vfio_device *device, 159 enum vfio_device_mig_state new_state); 160 int (*migration_get_state)(struct vfio_device *device, 161 enum vfio_device_mig_state *curr_state); 162 int (*migration_get_data_size)(struct vfio_device *device, 163 unsigned long *stop_copy_length); 164 }; 165 166 /** 167 * @log_start: Optional callback to ask the device start DMA logging. 168 * @log_stop: Optional callback to ask the device stop DMA logging. 169 * @log_read_and_clear: Optional callback to ask the device read 170 * and clear the dirty DMAs in some given range. 171 * 172 * The vfio core implementation of the DEVICE_FEATURE_DMA_LOGGING_ set 173 * of features does not track logging state relative to the device, 174 * therefore the device implementation of vfio_log_ops must handle 175 * arbitrary user requests. This includes rejecting subsequent calls 176 * to log_start without an intervening log_stop, as well as graceful 177 * handling of log_stop and log_read_and_clear from invalid states. 178 */ 179 struct vfio_log_ops { 180 int (*log_start)(struct vfio_device *device, 181 struct rb_root_cached *ranges, u32 nnodes, u64 *page_size); 182 int (*log_stop)(struct vfio_device *device); 183 int (*log_read_and_clear)(struct vfio_device *device, 184 unsigned long iova, unsigned long length, 185 struct iova_bitmap *dirty); 186 }; 187 188 /** 189 * vfio_check_feature - Validate user input for the VFIO_DEVICE_FEATURE ioctl 190 * @flags: Arg from the device_feature op 191 * @argsz: Arg from the device_feature op 192 * @supported_ops: Combination of VFIO_DEVICE_FEATURE_GET and SET the driver 193 * supports 194 * @minsz: Minimum data size the driver accepts 195 * 196 * For use in a driver's device_feature op. Checks that the inputs to the 197 * VFIO_DEVICE_FEATURE ioctl are correct for the driver's feature. Returns 1 if 198 * the driver should execute the get or set, otherwise the relevant 199 * value should be returned. 200 */ 201 static inline int vfio_check_feature(u32 flags, size_t argsz, u32 supported_ops, 202 size_t minsz) 203 { 204 if ((flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET)) & 205 ~supported_ops) 206 return -EINVAL; 207 if (flags & VFIO_DEVICE_FEATURE_PROBE) 208 return 0; 209 /* Without PROBE one of GET or SET must be requested */ 210 if (!(flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET))) 211 return -EINVAL; 212 if (argsz < minsz) 213 return -EINVAL; 214 return 1; 215 } 216 217 struct vfio_device *_vfio_alloc_device(size_t size, struct device *dev, 218 const struct vfio_device_ops *ops); 219 #define vfio_alloc_device(dev_struct, member, dev, ops) \ 220 container_of(_vfio_alloc_device(sizeof(struct dev_struct) + \ 221 BUILD_BUG_ON_ZERO(offsetof( \ 222 struct dev_struct, member)), \ 223 dev, ops), \ 224 struct dev_struct, member) 225 226 static inline void vfio_put_device(struct vfio_device *device) 227 { 228 put_device(&device->device); 229 } 230 231 int vfio_register_group_dev(struct vfio_device *device); 232 int vfio_register_emulated_iommu_dev(struct vfio_device *device); 233 void vfio_unregister_group_dev(struct vfio_device *device); 234 235 int vfio_assign_device_set(struct vfio_device *device, void *set_id); 236 unsigned int vfio_device_set_open_count(struct vfio_device_set *dev_set); 237 238 int vfio_mig_get_next_state(struct vfio_device *device, 239 enum vfio_device_mig_state cur_fsm, 240 enum vfio_device_mig_state new_fsm, 241 enum vfio_device_mig_state *next_fsm); 242 243 /* 244 * External user API 245 */ 246 struct iommu_group *vfio_file_iommu_group(struct file *file); 247 bool vfio_file_is_group(struct file *file); 248 bool vfio_file_enforced_coherent(struct file *file); 249 void vfio_file_set_kvm(struct file *file, struct kvm *kvm); 250 bool vfio_file_has_dev(struct file *file, struct vfio_device *device); 251 252 #define VFIO_PIN_PAGES_MAX_ENTRIES (PAGE_SIZE/sizeof(unsigned long)) 253 254 int vfio_pin_pages(struct vfio_device *device, dma_addr_t iova, 255 int npage, int prot, struct page **pages); 256 void vfio_unpin_pages(struct vfio_device *device, dma_addr_t iova, int npage); 257 int vfio_dma_rw(struct vfio_device *device, dma_addr_t iova, 258 void *data, size_t len, bool write); 259 260 /* 261 * Sub-module helpers 262 */ 263 struct vfio_info_cap { 264 struct vfio_info_cap_header *buf; 265 size_t size; 266 }; 267 struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps, 268 size_t size, u16 id, 269 u16 version); 270 void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset); 271 272 int vfio_info_add_capability(struct vfio_info_cap *caps, 273 struct vfio_info_cap_header *cap, size_t size); 274 275 int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr, 276 int num_irqs, int max_irq_type, 277 size_t *data_size); 278 279 /* 280 * IRQfd - generic 281 */ 282 struct virqfd { 283 void *opaque; 284 struct eventfd_ctx *eventfd; 285 int (*handler)(void *, void *); 286 void (*thread)(void *, void *); 287 void *data; 288 struct work_struct inject; 289 wait_queue_entry_t wait; 290 poll_table pt; 291 struct work_struct shutdown; 292 struct virqfd **pvirqfd; 293 }; 294 295 int vfio_virqfd_enable(void *opaque, int (*handler)(void *, void *), 296 void (*thread)(void *, void *), void *data, 297 struct virqfd **pvirqfd, int fd); 298 void vfio_virqfd_disable(struct virqfd **pvirqfd); 299 300 #endif /* VFIO_H */ 301