vhost-backend.c (12754B)
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 int ret; 28 29 assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL); 30 31 ret = ioctl(fd, request, arg); 32 return ret < 0 ? -errno : ret; 33 } 34 35 static int vhost_kernel_init(struct vhost_dev *dev, void *opaque, Error **errp) 36 { 37 assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL); 38 39 dev->opaque = opaque; 40 41 return 0; 42 } 43 44 static int vhost_kernel_cleanup(struct vhost_dev *dev) 45 { 46 int fd = (uintptr_t) dev->opaque; 47 48 assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL); 49 50 return close(fd) < 0 ? -errno : 0; 51 } 52 53 static int vhost_kernel_memslots_limit(struct vhost_dev *dev) 54 { 55 int limit = 64; 56 char *s; 57 58 if (g_file_get_contents("/sys/module/vhost/parameters/max_mem_regions", 59 &s, NULL, NULL)) { 60 uint64_t val = g_ascii_strtoull(s, NULL, 10); 61 if (val < INT_MAX && val > 0) { 62 g_free(s); 63 return val; 64 } 65 error_report("ignoring invalid max_mem_regions value in vhost module:" 66 " %s", s); 67 } 68 g_free(s); 69 return limit; 70 } 71 72 static int vhost_kernel_net_set_backend(struct vhost_dev *dev, 73 struct vhost_vring_file *file) 74 { 75 return vhost_kernel_call(dev, VHOST_NET_SET_BACKEND, file); 76 } 77 78 static int vhost_kernel_scsi_set_endpoint(struct vhost_dev *dev, 79 struct vhost_scsi_target *target) 80 { 81 return vhost_kernel_call(dev, VHOST_SCSI_SET_ENDPOINT, target); 82 } 83 84 static int vhost_kernel_scsi_clear_endpoint(struct vhost_dev *dev, 85 struct vhost_scsi_target *target) 86 { 87 return vhost_kernel_call(dev, VHOST_SCSI_CLEAR_ENDPOINT, target); 88 } 89 90 static int vhost_kernel_scsi_get_abi_version(struct vhost_dev *dev, int *version) 91 { 92 return vhost_kernel_call(dev, VHOST_SCSI_GET_ABI_VERSION, version); 93 } 94 95 static int vhost_kernel_set_log_base(struct vhost_dev *dev, uint64_t base, 96 struct vhost_log *log) 97 { 98 return vhost_kernel_call(dev, VHOST_SET_LOG_BASE, &base); 99 } 100 101 static int vhost_kernel_set_mem_table(struct vhost_dev *dev, 102 struct vhost_memory *mem) 103 { 104 return vhost_kernel_call(dev, VHOST_SET_MEM_TABLE, mem); 105 } 106 107 static int vhost_kernel_set_vring_addr(struct vhost_dev *dev, 108 struct vhost_vring_addr *addr) 109 { 110 return vhost_kernel_call(dev, VHOST_SET_VRING_ADDR, addr); 111 } 112 113 static int vhost_kernel_set_vring_endian(struct vhost_dev *dev, 114 struct vhost_vring_state *ring) 115 { 116 return vhost_kernel_call(dev, VHOST_SET_VRING_ENDIAN, ring); 117 } 118 119 static int vhost_kernel_set_vring_num(struct vhost_dev *dev, 120 struct vhost_vring_state *ring) 121 { 122 return vhost_kernel_call(dev, VHOST_SET_VRING_NUM, ring); 123 } 124 125 static int vhost_kernel_set_vring_base(struct vhost_dev *dev, 126 struct vhost_vring_state *ring) 127 { 128 return vhost_kernel_call(dev, VHOST_SET_VRING_BASE, ring); 129 } 130 131 static int vhost_kernel_get_vring_base(struct vhost_dev *dev, 132 struct vhost_vring_state *ring) 133 { 134 return vhost_kernel_call(dev, VHOST_GET_VRING_BASE, ring); 135 } 136 137 static int vhost_kernel_set_vring_kick(struct vhost_dev *dev, 138 struct vhost_vring_file *file) 139 { 140 return vhost_kernel_call(dev, VHOST_SET_VRING_KICK, file); 141 } 142 143 static int vhost_kernel_set_vring_call(struct vhost_dev *dev, 144 struct vhost_vring_file *file) 145 { 146 return vhost_kernel_call(dev, VHOST_SET_VRING_CALL, file); 147 } 148 149 static int vhost_kernel_set_vring_err(struct vhost_dev *dev, 150 struct vhost_vring_file *file) 151 { 152 return vhost_kernel_call(dev, VHOST_SET_VRING_ERR, file); 153 } 154 155 static int vhost_kernel_set_vring_busyloop_timeout(struct vhost_dev *dev, 156 struct vhost_vring_state *s) 157 { 158 return vhost_kernel_call(dev, VHOST_SET_VRING_BUSYLOOP_TIMEOUT, s); 159 } 160 161 static int vhost_kernel_set_features(struct vhost_dev *dev, 162 uint64_t features) 163 { 164 return vhost_kernel_call(dev, VHOST_SET_FEATURES, &features); 165 } 166 167 static int vhost_kernel_set_backend_cap(struct vhost_dev *dev) 168 { 169 uint64_t features; 170 uint64_t f = 0x1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2; 171 int r; 172 173 if (vhost_kernel_call(dev, VHOST_GET_BACKEND_FEATURES, &features)) { 174 return 0; 175 } 176 177 features &= f; 178 r = vhost_kernel_call(dev, VHOST_SET_BACKEND_FEATURES, 179 &features); 180 if (r) { 181 return 0; 182 } 183 184 dev->backend_cap = features; 185 186 return 0; 187 } 188 189 static int vhost_kernel_get_features(struct vhost_dev *dev, 190 uint64_t *features) 191 { 192 return vhost_kernel_call(dev, VHOST_GET_FEATURES, features); 193 } 194 195 static int vhost_kernel_set_owner(struct vhost_dev *dev) 196 { 197 return vhost_kernel_call(dev, VHOST_SET_OWNER, NULL); 198 } 199 200 static int vhost_kernel_reset_device(struct vhost_dev *dev) 201 { 202 return vhost_kernel_call(dev, VHOST_RESET_OWNER, NULL); 203 } 204 205 static int vhost_kernel_get_vq_index(struct vhost_dev *dev, int idx) 206 { 207 assert(idx >= dev->vq_index && idx < dev->vq_index + dev->nvqs); 208 209 return idx - dev->vq_index; 210 } 211 212 static int vhost_kernel_vsock_set_guest_cid(struct vhost_dev *dev, 213 uint64_t guest_cid) 214 { 215 return vhost_kernel_call(dev, VHOST_VSOCK_SET_GUEST_CID, &guest_cid); 216 } 217 218 static int vhost_kernel_vsock_set_running(struct vhost_dev *dev, int start) 219 { 220 return vhost_kernel_call(dev, VHOST_VSOCK_SET_RUNNING, &start); 221 } 222 223 static void vhost_kernel_iotlb_read(void *opaque) 224 { 225 struct vhost_dev *dev = opaque; 226 ssize_t len; 227 228 if (dev->backend_cap & 229 (0x1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2)) { 230 struct vhost_msg_v2 msg; 231 232 while ((len = read((uintptr_t)dev->opaque, &msg, sizeof msg)) > 0) { 233 if (len < sizeof msg) { 234 error_report("Wrong vhost message len: %d", (int)len); 235 break; 236 } 237 if (msg.type != VHOST_IOTLB_MSG_V2) { 238 error_report("Unknown vhost iotlb message type"); 239 break; 240 } 241 242 vhost_backend_handle_iotlb_msg(dev, &msg.iotlb); 243 } 244 } else { 245 struct vhost_msg msg; 246 247 while ((len = read((uintptr_t)dev->opaque, &msg, sizeof msg)) > 0) { 248 if (len < sizeof msg) { 249 error_report("Wrong vhost message len: %d", (int)len); 250 break; 251 } 252 if (msg.type != VHOST_IOTLB_MSG) { 253 error_report("Unknown vhost iotlb message type"); 254 break; 255 } 256 257 vhost_backend_handle_iotlb_msg(dev, &msg.iotlb); 258 } 259 } 260 } 261 262 static int vhost_kernel_send_device_iotlb_msg(struct vhost_dev *dev, 263 struct vhost_iotlb_msg *imsg) 264 { 265 if (dev->backend_cap & (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2)) { 266 struct vhost_msg_v2 msg = {}; 267 268 msg.type = VHOST_IOTLB_MSG_V2; 269 msg.iotlb = *imsg; 270 271 if (write((uintptr_t)dev->opaque, &msg, sizeof msg) != sizeof msg) { 272 error_report("Fail to update device iotlb"); 273 return -EFAULT; 274 } 275 } else { 276 struct vhost_msg msg = {}; 277 278 msg.type = VHOST_IOTLB_MSG; 279 msg.iotlb = *imsg; 280 281 if (write((uintptr_t)dev->opaque, &msg, sizeof msg) != sizeof msg) { 282 error_report("Fail to update device iotlb"); 283 return -EFAULT; 284 } 285 } 286 287 return 0; 288 } 289 290 static void vhost_kernel_set_iotlb_callback(struct vhost_dev *dev, 291 int enabled) 292 { 293 if (enabled) 294 qemu_set_fd_handler((uintptr_t)dev->opaque, 295 vhost_kernel_iotlb_read, NULL, dev); 296 else 297 qemu_set_fd_handler((uintptr_t)dev->opaque, NULL, NULL, NULL); 298 } 299 300 const VhostOps kernel_ops = { 301 .backend_type = VHOST_BACKEND_TYPE_KERNEL, 302 .vhost_backend_init = vhost_kernel_init, 303 .vhost_backend_cleanup = vhost_kernel_cleanup, 304 .vhost_backend_memslots_limit = vhost_kernel_memslots_limit, 305 .vhost_net_set_backend = vhost_kernel_net_set_backend, 306 .vhost_scsi_set_endpoint = vhost_kernel_scsi_set_endpoint, 307 .vhost_scsi_clear_endpoint = vhost_kernel_scsi_clear_endpoint, 308 .vhost_scsi_get_abi_version = vhost_kernel_scsi_get_abi_version, 309 .vhost_set_log_base = vhost_kernel_set_log_base, 310 .vhost_set_mem_table = vhost_kernel_set_mem_table, 311 .vhost_set_vring_addr = vhost_kernel_set_vring_addr, 312 .vhost_set_vring_endian = vhost_kernel_set_vring_endian, 313 .vhost_set_vring_num = vhost_kernel_set_vring_num, 314 .vhost_set_vring_base = vhost_kernel_set_vring_base, 315 .vhost_get_vring_base = vhost_kernel_get_vring_base, 316 .vhost_set_vring_kick = vhost_kernel_set_vring_kick, 317 .vhost_set_vring_call = vhost_kernel_set_vring_call, 318 .vhost_set_vring_err = vhost_kernel_set_vring_err, 319 .vhost_set_vring_busyloop_timeout = 320 vhost_kernel_set_vring_busyloop_timeout, 321 .vhost_set_features = vhost_kernel_set_features, 322 .vhost_get_features = vhost_kernel_get_features, 323 .vhost_set_backend_cap = vhost_kernel_set_backend_cap, 324 .vhost_set_owner = vhost_kernel_set_owner, 325 .vhost_reset_device = vhost_kernel_reset_device, 326 .vhost_get_vq_index = vhost_kernel_get_vq_index, 327 .vhost_vsock_set_guest_cid = vhost_kernel_vsock_set_guest_cid, 328 .vhost_vsock_set_running = vhost_kernel_vsock_set_running, 329 .vhost_set_iotlb_callback = vhost_kernel_set_iotlb_callback, 330 .vhost_send_device_iotlb_msg = vhost_kernel_send_device_iotlb_msg, 331 }; 332 #endif 333 334 int vhost_backend_update_device_iotlb(struct vhost_dev *dev, 335 uint64_t iova, uint64_t uaddr, 336 uint64_t len, 337 IOMMUAccessFlags perm) 338 { 339 struct vhost_iotlb_msg imsg; 340 341 imsg.iova = iova; 342 imsg.uaddr = uaddr; 343 imsg.size = len; 344 imsg.type = VHOST_IOTLB_UPDATE; 345 346 switch (perm) { 347 case IOMMU_RO: 348 imsg.perm = VHOST_ACCESS_RO; 349 break; 350 case IOMMU_WO: 351 imsg.perm = VHOST_ACCESS_WO; 352 break; 353 case IOMMU_RW: 354 imsg.perm = VHOST_ACCESS_RW; 355 break; 356 default: 357 return -EINVAL; 358 } 359 360 if (dev->vhost_ops && dev->vhost_ops->vhost_send_device_iotlb_msg) 361 return dev->vhost_ops->vhost_send_device_iotlb_msg(dev, &imsg); 362 363 return -ENODEV; 364 } 365 366 int vhost_backend_invalidate_device_iotlb(struct vhost_dev *dev, 367 uint64_t iova, uint64_t len) 368 { 369 struct vhost_iotlb_msg imsg; 370 371 imsg.iova = iova; 372 imsg.size = len; 373 imsg.type = VHOST_IOTLB_INVALIDATE; 374 375 if (dev->vhost_ops && dev->vhost_ops->vhost_send_device_iotlb_msg) 376 return dev->vhost_ops->vhost_send_device_iotlb_msg(dev, &imsg); 377 378 return -ENODEV; 379 } 380 381 int vhost_backend_handle_iotlb_msg(struct vhost_dev *dev, 382 struct vhost_iotlb_msg *imsg) 383 { 384 int ret = 0; 385 386 if (unlikely(!dev->vdev)) { 387 error_report("Unexpected IOTLB message when virtio device is stopped"); 388 return -EINVAL; 389 } 390 391 switch (imsg->type) { 392 case VHOST_IOTLB_MISS: 393 ret = vhost_device_iotlb_miss(dev, imsg->iova, 394 imsg->perm != VHOST_ACCESS_RO); 395 break; 396 case VHOST_IOTLB_ACCESS_FAIL: 397 /* FIXME: report device iotlb error */ 398 error_report("Access failure IOTLB message type not supported"); 399 ret = -ENOTSUP; 400 break; 401 case VHOST_IOTLB_UPDATE: 402 case VHOST_IOTLB_INVALIDATE: 403 default: 404 error_report("Unexpected IOTLB message type"); 405 ret = -EINVAL; 406 break; 407 } 408 409 return ret; 410 }