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 #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 struct iommufd_ctx *iommufd_ictx; 64 bool iommufd_attached; 65 #endif 66 }; 67 68 /** 69 * struct vfio_device_ops - VFIO bus driver device callbacks 70 * 71 * @init: initialize private fields in device structure 72 * @release: Reclaim private fields in device structure 73 * @bind_iommufd: Called when binding the device to an iommufd 74 * @unbind_iommufd: Opposite of bind_iommufd 75 * @attach_ioas: Called when attaching device to an IOAS/HWPT managed by the 76 * bound iommufd. Undo in unbind_iommufd. 77 * @open_device: Called when the first file descriptor is opened for this device 78 * @close_device: Opposite of open_device 79 * @read: Perform read(2) on device file descriptor 80 * @write: Perform write(2) on device file descriptor 81 * @ioctl: Perform ioctl(2) on device file descriptor, supporting VFIO_DEVICE_* 82 * operations documented below 83 * @mmap: Perform mmap(2) on a region of the device file descriptor 84 * @request: Request for the bus driver to release the device 85 * @match: Optional device name match callback (return: 0 for no-match, >0 for 86 * match, -errno for abort (ex. match with insufficient or incorrect 87 * additional args) 88 * @dma_unmap: Called when userspace unmaps IOVA from the container 89 * this device is attached to. 90 * @device_feature: Optional, fill in the VFIO_DEVICE_FEATURE ioctl 91 */ 92 struct vfio_device_ops { 93 char *name; 94 int (*init)(struct vfio_device *vdev); 95 void (*release)(struct vfio_device *vdev); 96 int (*bind_iommufd)(struct vfio_device *vdev, 97 struct iommufd_ctx *ictx, u32 *out_device_id); 98 void (*unbind_iommufd)(struct vfio_device *vdev); 99 int (*attach_ioas)(struct vfio_device *vdev, u32 *pt_id); 100 int (*open_device)(struct vfio_device *vdev); 101 void (*close_device)(struct vfio_device *vdev); 102 ssize_t (*read)(struct vfio_device *vdev, char __user *buf, 103 size_t count, loff_t *ppos); 104 ssize_t (*write)(struct vfio_device *vdev, const char __user *buf, 105 size_t count, loff_t *size); 106 long (*ioctl)(struct vfio_device *vdev, unsigned int cmd, 107 unsigned long arg); 108 int (*mmap)(struct vfio_device *vdev, struct vm_area_struct *vma); 109 void (*request)(struct vfio_device *vdev, unsigned int count); 110 int (*match)(struct vfio_device *vdev, char *buf); 111 void (*dma_unmap)(struct vfio_device *vdev, u64 iova, u64 length); 112 int (*device_feature)(struct vfio_device *device, u32 flags, 113 void __user *arg, size_t argsz); 114 }; 115 116 #if IS_ENABLED(CONFIG_IOMMUFD) 117 int vfio_iommufd_physical_bind(struct vfio_device *vdev, 118 struct iommufd_ctx *ictx, u32 *out_device_id); 119 void vfio_iommufd_physical_unbind(struct vfio_device *vdev); 120 int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id); 121 int vfio_iommufd_emulated_bind(struct vfio_device *vdev, 122 struct iommufd_ctx *ictx, u32 *out_device_id); 123 void vfio_iommufd_emulated_unbind(struct vfio_device *vdev); 124 int vfio_iommufd_emulated_attach_ioas(struct vfio_device *vdev, u32 *pt_id); 125 #else 126 #define vfio_iommufd_physical_bind \ 127 ((int (*)(struct vfio_device *vdev, struct iommufd_ctx *ictx, \ 128 u32 *out_device_id)) NULL) 129 #define vfio_iommufd_physical_unbind \ 130 ((void (*)(struct vfio_device *vdev)) NULL) 131 #define vfio_iommufd_physical_attach_ioas \ 132 ((int (*)(struct vfio_device *vdev, u32 *pt_id)) NULL) 133 #define vfio_iommufd_emulated_bind \ 134 ((int (*)(struct vfio_device *vdev, struct iommufd_ctx *ictx, \ 135 u32 *out_device_id)) NULL) 136 #define vfio_iommufd_emulated_unbind \ 137 ((void (*)(struct vfio_device *vdev)) NULL) 138 #define vfio_iommufd_emulated_attach_ioas \ 139 ((int (*)(struct vfio_device *vdev, u32 *pt_id)) NULL) 140 #endif 141 142 /** 143 * @migration_set_state: Optional callback to change the migration state for 144 * devices that support migration. It's mandatory for 145 * VFIO_DEVICE_FEATURE_MIGRATION migration support. 146 * The returned FD is used for data transfer according to the FSM 147 * definition. The driver is responsible to ensure that FD reaches end 148 * of stream or error whenever the migration FSM leaves a data transfer 149 * state or before close_device() returns. 150 * @migration_get_state: Optional callback to get the migration state for 151 * devices that support migration. It's mandatory for 152 * VFIO_DEVICE_FEATURE_MIGRATION migration support. 153 * @migration_get_data_size: Optional callback to get the estimated data 154 * length that will be required to complete stop copy. It's mandatory for 155 * VFIO_DEVICE_FEATURE_MIGRATION migration support. 156 */ 157 struct vfio_migration_ops { 158 struct file *(*migration_set_state)( 159 struct vfio_device *device, 160 enum vfio_device_mig_state new_state); 161 int (*migration_get_state)(struct vfio_device *device, 162 enum vfio_device_mig_state *curr_state); 163 int (*migration_get_data_size)(struct vfio_device *device, 164 unsigned long *stop_copy_length); 165 }; 166 167 /** 168 * @log_start: Optional callback to ask the device start DMA logging. 169 * @log_stop: Optional callback to ask the device stop DMA logging. 170 * @log_read_and_clear: Optional callback to ask the device read 171 * and clear the dirty DMAs in some given range. 172 * 173 * The vfio core implementation of the DEVICE_FEATURE_DMA_LOGGING_ set 174 * of features does not track logging state relative to the device, 175 * therefore the device implementation of vfio_log_ops must handle 176 * arbitrary user requests. This includes rejecting subsequent calls 177 * to log_start without an intervening log_stop, as well as graceful 178 * handling of log_stop and log_read_and_clear from invalid states. 179 */ 180 struct vfio_log_ops { 181 int (*log_start)(struct vfio_device *device, 182 struct rb_root_cached *ranges, u32 nnodes, u64 *page_size); 183 int (*log_stop)(struct vfio_device *device); 184 int (*log_read_and_clear)(struct vfio_device *device, 185 unsigned long iova, unsigned long length, 186 struct iova_bitmap *dirty); 187 }; 188 189 /** 190 * vfio_check_feature - Validate user input for the VFIO_DEVICE_FEATURE ioctl 191 * @flags: Arg from the device_feature op 192 * @argsz: Arg from the device_feature op 193 * @supported_ops: Combination of VFIO_DEVICE_FEATURE_GET and SET the driver 194 * supports 195 * @minsz: Minimum data size the driver accepts 196 * 197 * For use in a driver's device_feature op. Checks that the inputs to the 198 * VFIO_DEVICE_FEATURE ioctl are correct for the driver's feature. Returns 1 if 199 * the driver should execute the get or set, otherwise the relevant 200 * value should be returned. 201 */ vfio_check_feature(u32 flags,size_t argsz,u32 supported_ops,size_t minsz)202 static inline int vfio_check_feature(u32 flags, size_t argsz, u32 supported_ops, 203 size_t minsz) 204 { 205 if ((flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET)) & 206 ~supported_ops) 207 return -EINVAL; 208 if (flags & VFIO_DEVICE_FEATURE_PROBE) 209 return 0; 210 /* Without PROBE one of GET or SET must be requested */ 211 if (!(flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET))) 212 return -EINVAL; 213 if (argsz < minsz) 214 return -EINVAL; 215 return 1; 216 } 217 218 struct vfio_device *_vfio_alloc_device(size_t size, struct device *dev, 219 const struct vfio_device_ops *ops); 220 #define vfio_alloc_device(dev_struct, member, dev, ops) \ 221 container_of(_vfio_alloc_device(sizeof(struct dev_struct) + \ 222 BUILD_BUG_ON_ZERO(offsetof( \ 223 struct dev_struct, member)), \ 224 dev, ops), \ 225 struct dev_struct, member) 226 vfio_put_device(struct vfio_device * device)227 static inline void vfio_put_device(struct vfio_device *device) 228 { 229 put_device(&device->device); 230 } 231 232 int vfio_register_group_dev(struct vfio_device *device); 233 int vfio_register_emulated_iommu_dev(struct vfio_device *device); 234 void vfio_unregister_group_dev(struct vfio_device *device); 235 236 int vfio_assign_device_set(struct vfio_device *device, void *set_id); 237 unsigned int vfio_device_set_open_count(struct vfio_device_set *dev_set); 238 239 int vfio_mig_get_next_state(struct vfio_device *device, 240 enum vfio_device_mig_state cur_fsm, 241 enum vfio_device_mig_state new_fsm, 242 enum vfio_device_mig_state *next_fsm); 243 244 /* 245 * External user API 246 */ 247 struct iommu_group *vfio_file_iommu_group(struct file *file); 248 bool vfio_file_is_group(struct file *file); 249 bool vfio_file_enforced_coherent(struct file *file); 250 void vfio_file_set_kvm(struct file *file, struct kvm *kvm); 251 bool vfio_file_has_dev(struct file *file, struct vfio_device *device); 252 253 #define VFIO_PIN_PAGES_MAX_ENTRIES (PAGE_SIZE/sizeof(unsigned long)) 254 255 int vfio_pin_pages(struct vfio_device *device, dma_addr_t iova, 256 int npage, int prot, struct page **pages); 257 void vfio_unpin_pages(struct vfio_device *device, dma_addr_t iova, int npage); 258 int vfio_dma_rw(struct vfio_device *device, dma_addr_t iova, 259 void *data, size_t len, bool write); 260 261 /* 262 * Sub-module helpers 263 */ 264 struct vfio_info_cap { 265 struct vfio_info_cap_header *buf; 266 size_t size; 267 }; 268 struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps, 269 size_t size, u16 id, 270 u16 version); 271 void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset); 272 273 int vfio_info_add_capability(struct vfio_info_cap *caps, 274 struct vfio_info_cap_header *cap, size_t size); 275 276 int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr, 277 int num_irqs, int max_irq_type, 278 size_t *data_size); 279 280 /* 281 * IRQfd - generic 282 */ 283 struct virqfd { 284 void *opaque; 285 struct eventfd_ctx *eventfd; 286 int (*handler)(void *, void *); 287 void (*thread)(void *, void *); 288 void *data; 289 struct work_struct inject; 290 wait_queue_entry_t wait; 291 poll_table pt; 292 struct work_struct shutdown; 293 struct virqfd **pvirqfd; 294 }; 295 296 int vfio_virqfd_enable(void *opaque, int (*handler)(void *, void *), 297 void (*thread)(void *, void *), void *data, 298 struct virqfd **pvirqfd, int fd); 299 void vfio_virqfd_disable(struct virqfd **pvirqfd); 300 301 #endif /* VFIO_H */ 302