1 /* 2 * vhost-backend 3 * 4 * Copyright (c) 2013 Virtual Open Systems Sarl. 5 * 6 * This work is licensed under the terms of the GNU GPL, version 2 or later. 7 * See the COPYING file in the top-level directory. 8 * 9 */ 10 11 #include "qemu/osdep.h" 12 #include "hw/virtio/vhost.h" 13 #include "hw/virtio/vhost-backend.h" 14 #include "qemu/error-report.h" 15 #include "qemu/main-loop.h" 16 #include "standard-headers/linux/vhost_types.h" 17 18 #include "hw/virtio/vhost-vdpa.h" 19 #ifdef CONFIG_VHOST_KERNEL 20 #include <linux/vhost.h> 21 #include <sys/ioctl.h> 22 23 static int vhost_kernel_call(struct vhost_dev *dev, unsigned long int request, 24 void *arg) 25 { 26 int fd = (uintptr_t) dev->opaque; 27 28 assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL); 29 30 return ioctl(fd, request, arg); 31 } 32 33 static int vhost_kernel_init(struct vhost_dev *dev, void *opaque) 34 { 35 assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL); 36 37 dev->opaque = opaque; 38 39 return 0; 40 } 41 42 static int vhost_kernel_cleanup(struct vhost_dev *dev) 43 { 44 int fd = (uintptr_t) dev->opaque; 45 46 assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL); 47 48 return close(fd); 49 } 50 51 static int vhost_kernel_memslots_limit(struct vhost_dev *dev) 52 { 53 int limit = 64; 54 char *s; 55 56 if (g_file_get_contents("/sys/module/vhost/parameters/max_mem_regions", 57 &s, NULL, NULL)) { 58 uint64_t val = g_ascii_strtoull(s, NULL, 10); 59 if (!((val == G_MAXUINT64 || !val) && errno)) { 60 g_free(s); 61 return val; 62 } 63 error_report("ignoring invalid max_mem_regions value in vhost module:" 64 " %s", s); 65 } 66 g_free(s); 67 return limit; 68 } 69 70 static int vhost_kernel_net_set_backend(struct vhost_dev *dev, 71 struct vhost_vring_file *file) 72 { 73 return vhost_kernel_call(dev, VHOST_NET_SET_BACKEND, file); 74 } 75 76 static int vhost_kernel_scsi_set_endpoint(struct vhost_dev *dev, 77 struct vhost_scsi_target *target) 78 { 79 return vhost_kernel_call(dev, VHOST_SCSI_SET_ENDPOINT, target); 80 } 81 82 static int vhost_kernel_scsi_clear_endpoint(struct vhost_dev *dev, 83 struct vhost_scsi_target *target) 84 { 85 return vhost_kernel_call(dev, VHOST_SCSI_CLEAR_ENDPOINT, target); 86 } 87 88 static int vhost_kernel_scsi_get_abi_version(struct vhost_dev *dev, int *version) 89 { 90 return vhost_kernel_call(dev, VHOST_SCSI_GET_ABI_VERSION, version); 91 } 92 93 static int vhost_kernel_set_log_base(struct vhost_dev *dev, uint64_t base, 94 struct vhost_log *log) 95 { 96 return vhost_kernel_call(dev, VHOST_SET_LOG_BASE, &base); 97 } 98 99 static int vhost_kernel_set_mem_table(struct vhost_dev *dev, 100 struct vhost_memory *mem) 101 { 102 return vhost_kernel_call(dev, VHOST_SET_MEM_TABLE, mem); 103 } 104 105 static int vhost_kernel_set_vring_addr(struct vhost_dev *dev, 106 struct vhost_vring_addr *addr) 107 { 108 return vhost_kernel_call(dev, VHOST_SET_VRING_ADDR, addr); 109 } 110 111 static int vhost_kernel_set_vring_endian(struct vhost_dev *dev, 112 struct vhost_vring_state *ring) 113 { 114 return vhost_kernel_call(dev, VHOST_SET_VRING_ENDIAN, ring); 115 } 116 117 static int vhost_kernel_set_vring_num(struct vhost_dev *dev, 118 struct vhost_vring_state *ring) 119 { 120 return vhost_kernel_call(dev, VHOST_SET_VRING_NUM, ring); 121 } 122 123 static int vhost_kernel_set_vring_base(struct vhost_dev *dev, 124 struct vhost_vring_state *ring) 125 { 126 return vhost_kernel_call(dev, VHOST_SET_VRING_BASE, ring); 127 } 128 129 static int vhost_kernel_get_vring_base(struct vhost_dev *dev, 130 struct vhost_vring_state *ring) 131 { 132 return vhost_kernel_call(dev, VHOST_GET_VRING_BASE, ring); 133 } 134 135 static int vhost_kernel_set_vring_kick(struct vhost_dev *dev, 136 struct vhost_vring_file *file) 137 { 138 return vhost_kernel_call(dev, VHOST_SET_VRING_KICK, file); 139 } 140 141 static int vhost_kernel_set_vring_call(struct vhost_dev *dev, 142 struct vhost_vring_file *file) 143 { 144 return vhost_kernel_call(dev, VHOST_SET_VRING_CALL, file); 145 } 146 147 static int vhost_kernel_set_vring_busyloop_timeout(struct vhost_dev *dev, 148 struct vhost_vring_state *s) 149 { 150 return vhost_kernel_call(dev, VHOST_SET_VRING_BUSYLOOP_TIMEOUT, s); 151 } 152 153 static int vhost_kernel_set_features(struct vhost_dev *dev, 154 uint64_t features) 155 { 156 return vhost_kernel_call(dev, VHOST_SET_FEATURES, &features); 157 } 158 159 static int vhost_kernel_set_backend_cap(struct vhost_dev *dev) 160 { 161 uint64_t features; 162 uint64_t f = 0x1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2; 163 int r; 164 165 if (vhost_kernel_call(dev, VHOST_GET_BACKEND_FEATURES, &features)) { 166 return 0; 167 } 168 169 features &= f; 170 r = vhost_kernel_call(dev, VHOST_SET_BACKEND_FEATURES, 171 &features); 172 if (r) { 173 return 0; 174 } 175 176 dev->backend_cap = features; 177 178 return 0; 179 } 180 181 static int vhost_kernel_get_features(struct vhost_dev *dev, 182 uint64_t *features) 183 { 184 return vhost_kernel_call(dev, VHOST_GET_FEATURES, features); 185 } 186 187 static int vhost_kernel_set_owner(struct vhost_dev *dev) 188 { 189 return vhost_kernel_call(dev, VHOST_SET_OWNER, NULL); 190 } 191 192 static int vhost_kernel_reset_device(struct vhost_dev *dev) 193 { 194 return vhost_kernel_call(dev, VHOST_RESET_OWNER, NULL); 195 } 196 197 static int vhost_kernel_get_vq_index(struct vhost_dev *dev, int idx) 198 { 199 assert(idx >= dev->vq_index && idx < dev->vq_index + dev->nvqs); 200 201 return idx - dev->vq_index; 202 } 203 204 #ifdef CONFIG_VHOST_VSOCK 205 static int vhost_kernel_vsock_set_guest_cid(struct vhost_dev *dev, 206 uint64_t guest_cid) 207 { 208 return vhost_kernel_call(dev, VHOST_VSOCK_SET_GUEST_CID, &guest_cid); 209 } 210 211 static int vhost_kernel_vsock_set_running(struct vhost_dev *dev, int start) 212 { 213 return vhost_kernel_call(dev, VHOST_VSOCK_SET_RUNNING, &start); 214 } 215 #endif /* CONFIG_VHOST_VSOCK */ 216 217 static void vhost_kernel_iotlb_read(void *opaque) 218 { 219 struct vhost_dev *dev = opaque; 220 ssize_t len; 221 222 if (dev->backend_cap & 223 (0x1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2)) { 224 struct vhost_msg_v2 msg; 225 226 while ((len = read((uintptr_t)dev->opaque, &msg, sizeof msg)) > 0) { 227 if (len < sizeof msg) { 228 error_report("Wrong vhost message len: %d", (int)len); 229 break; 230 } 231 if (msg.type != VHOST_IOTLB_MSG_V2) { 232 error_report("Unknown vhost iotlb message type"); 233 break; 234 } 235 236 vhost_backend_handle_iotlb_msg(dev, &msg.iotlb); 237 } 238 } else { 239 struct vhost_msg msg; 240 241 while ((len = read((uintptr_t)dev->opaque, &msg, sizeof msg)) > 0) { 242 if (len < sizeof msg) { 243 error_report("Wrong vhost message len: %d", (int)len); 244 break; 245 } 246 if (msg.type != VHOST_IOTLB_MSG) { 247 error_report("Unknown vhost iotlb message type"); 248 break; 249 } 250 251 vhost_backend_handle_iotlb_msg(dev, &msg.iotlb); 252 } 253 } 254 } 255 256 static int vhost_kernel_send_device_iotlb_msg(struct vhost_dev *dev, 257 struct vhost_iotlb_msg *imsg) 258 { 259 if (dev->backend_cap & (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2)) { 260 struct vhost_msg_v2 msg = {}; 261 262 msg.type = VHOST_IOTLB_MSG_V2; 263 msg.iotlb = *imsg; 264 265 if (write((uintptr_t)dev->opaque, &msg, sizeof msg) != sizeof msg) { 266 error_report("Fail to update device iotlb"); 267 return -EFAULT; 268 } 269 } else { 270 struct vhost_msg msg = {}; 271 272 msg.type = VHOST_IOTLB_MSG; 273 msg.iotlb = *imsg; 274 275 if (write((uintptr_t)dev->opaque, &msg, sizeof msg) != sizeof msg) { 276 error_report("Fail to update device iotlb"); 277 return -EFAULT; 278 } 279 } 280 281 return 0; 282 } 283 284 static void vhost_kernel_set_iotlb_callback(struct vhost_dev *dev, 285 int enabled) 286 { 287 if (enabled) 288 qemu_set_fd_handler((uintptr_t)dev->opaque, 289 vhost_kernel_iotlb_read, NULL, dev); 290 else 291 qemu_set_fd_handler((uintptr_t)dev->opaque, NULL, NULL, NULL); 292 } 293 294 static const VhostOps kernel_ops = { 295 .backend_type = VHOST_BACKEND_TYPE_KERNEL, 296 .vhost_backend_init = vhost_kernel_init, 297 .vhost_backend_cleanup = vhost_kernel_cleanup, 298 .vhost_backend_memslots_limit = vhost_kernel_memslots_limit, 299 .vhost_net_set_backend = vhost_kernel_net_set_backend, 300 .vhost_scsi_set_endpoint = vhost_kernel_scsi_set_endpoint, 301 .vhost_scsi_clear_endpoint = vhost_kernel_scsi_clear_endpoint, 302 .vhost_scsi_get_abi_version = vhost_kernel_scsi_get_abi_version, 303 .vhost_set_log_base = vhost_kernel_set_log_base, 304 .vhost_set_mem_table = vhost_kernel_set_mem_table, 305 .vhost_set_vring_addr = vhost_kernel_set_vring_addr, 306 .vhost_set_vring_endian = vhost_kernel_set_vring_endian, 307 .vhost_set_vring_num = vhost_kernel_set_vring_num, 308 .vhost_set_vring_base = vhost_kernel_set_vring_base, 309 .vhost_get_vring_base = vhost_kernel_get_vring_base, 310 .vhost_set_vring_kick = vhost_kernel_set_vring_kick, 311 .vhost_set_vring_call = vhost_kernel_set_vring_call, 312 .vhost_set_vring_busyloop_timeout = 313 vhost_kernel_set_vring_busyloop_timeout, 314 .vhost_set_features = vhost_kernel_set_features, 315 .vhost_get_features = vhost_kernel_get_features, 316 .vhost_set_backend_cap = vhost_kernel_set_backend_cap, 317 .vhost_set_owner = vhost_kernel_set_owner, 318 .vhost_reset_device = vhost_kernel_reset_device, 319 .vhost_get_vq_index = vhost_kernel_get_vq_index, 320 #ifdef CONFIG_VHOST_VSOCK 321 .vhost_vsock_set_guest_cid = vhost_kernel_vsock_set_guest_cid, 322 .vhost_vsock_set_running = vhost_kernel_vsock_set_running, 323 #endif /* CONFIG_VHOST_VSOCK */ 324 .vhost_set_iotlb_callback = vhost_kernel_set_iotlb_callback, 325 .vhost_send_device_iotlb_msg = vhost_kernel_send_device_iotlb_msg, 326 }; 327 #endif 328 329 int vhost_set_backend_type(struct vhost_dev *dev, VhostBackendType backend_type) 330 { 331 int r = 0; 332 333 switch (backend_type) { 334 #ifdef CONFIG_VHOST_KERNEL 335 case VHOST_BACKEND_TYPE_KERNEL: 336 dev->vhost_ops = &kernel_ops; 337 break; 338 #endif 339 #ifdef CONFIG_VHOST_USER 340 case VHOST_BACKEND_TYPE_USER: 341 dev->vhost_ops = &user_ops; 342 break; 343 #endif 344 #ifdef CONFIG_VHOST_VDPA 345 case VHOST_BACKEND_TYPE_VDPA: 346 dev->vhost_ops = &vdpa_ops; 347 break; 348 #endif 349 default: 350 error_report("Unknown vhost backend type"); 351 r = -1; 352 } 353 354 return r; 355 } 356 357 int vhost_backend_update_device_iotlb(struct vhost_dev *dev, 358 uint64_t iova, uint64_t uaddr, 359 uint64_t len, 360 IOMMUAccessFlags perm) 361 { 362 struct vhost_iotlb_msg imsg; 363 364 imsg.iova = iova; 365 imsg.uaddr = uaddr; 366 imsg.size = len; 367 imsg.type = VHOST_IOTLB_UPDATE; 368 369 switch (perm) { 370 case IOMMU_RO: 371 imsg.perm = VHOST_ACCESS_RO; 372 break; 373 case IOMMU_WO: 374 imsg.perm = VHOST_ACCESS_WO; 375 break; 376 case IOMMU_RW: 377 imsg.perm = VHOST_ACCESS_RW; 378 break; 379 default: 380 return -EINVAL; 381 } 382 383 if (dev->vhost_ops && dev->vhost_ops->vhost_send_device_iotlb_msg) 384 return dev->vhost_ops->vhost_send_device_iotlb_msg(dev, &imsg); 385 386 return -ENODEV; 387 } 388 389 int vhost_backend_invalidate_device_iotlb(struct vhost_dev *dev, 390 uint64_t iova, uint64_t len) 391 { 392 struct vhost_iotlb_msg imsg; 393 394 imsg.iova = iova; 395 imsg.size = len; 396 imsg.type = VHOST_IOTLB_INVALIDATE; 397 398 if (dev->vhost_ops && dev->vhost_ops->vhost_send_device_iotlb_msg) 399 return dev->vhost_ops->vhost_send_device_iotlb_msg(dev, &imsg); 400 401 return -ENODEV; 402 } 403 404 int vhost_backend_handle_iotlb_msg(struct vhost_dev *dev, 405 struct vhost_iotlb_msg *imsg) 406 { 407 int ret = 0; 408 409 switch (imsg->type) { 410 case VHOST_IOTLB_MISS: 411 ret = vhost_device_iotlb_miss(dev, imsg->iova, 412 imsg->perm != VHOST_ACCESS_RO); 413 break; 414 case VHOST_IOTLB_ACCESS_FAIL: 415 /* FIXME: report device iotlb error */ 416 error_report("Access failure IOTLB message type not supported"); 417 ret = -ENOTSUP; 418 break; 419 case VHOST_IOTLB_UPDATE: 420 case VHOST_IOTLB_INVALIDATE: 421 default: 422 error_report("Unexpected IOTLB message type"); 423 ret = -EINVAL; 424 break; 425 } 426 427 return ret; 428 } 429