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_busyloop_timeout(struct vhost_dev *dev, 150 struct vhost_vring_state *s) 151 { 152 return vhost_kernel_call(dev, VHOST_SET_VRING_BUSYLOOP_TIMEOUT, s); 153 } 154 155 static int vhost_kernel_set_features(struct vhost_dev *dev, 156 uint64_t features) 157 { 158 return vhost_kernel_call(dev, VHOST_SET_FEATURES, &features); 159 } 160 161 static int vhost_kernel_set_backend_cap(struct vhost_dev *dev) 162 { 163 uint64_t features; 164 uint64_t f = 0x1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2; 165 int r; 166 167 if (vhost_kernel_call(dev, VHOST_GET_BACKEND_FEATURES, &features)) { 168 return 0; 169 } 170 171 features &= f; 172 r = vhost_kernel_call(dev, VHOST_SET_BACKEND_FEATURES, 173 &features); 174 if (r) { 175 return 0; 176 } 177 178 dev->backend_cap = features; 179 180 return 0; 181 } 182 183 static int vhost_kernel_get_features(struct vhost_dev *dev, 184 uint64_t *features) 185 { 186 return vhost_kernel_call(dev, VHOST_GET_FEATURES, features); 187 } 188 189 static int vhost_kernel_set_owner(struct vhost_dev *dev) 190 { 191 return vhost_kernel_call(dev, VHOST_SET_OWNER, NULL); 192 } 193 194 static int vhost_kernel_reset_device(struct vhost_dev *dev) 195 { 196 return vhost_kernel_call(dev, VHOST_RESET_OWNER, NULL); 197 } 198 199 static int vhost_kernel_get_vq_index(struct vhost_dev *dev, int idx) 200 { 201 assert(idx >= dev->vq_index && idx < dev->vq_index + dev->nvqs); 202 203 return idx - dev->vq_index; 204 } 205 206 static int vhost_kernel_vsock_set_guest_cid(struct vhost_dev *dev, 207 uint64_t guest_cid) 208 { 209 return vhost_kernel_call(dev, VHOST_VSOCK_SET_GUEST_CID, &guest_cid); 210 } 211 212 static int vhost_kernel_vsock_set_running(struct vhost_dev *dev, int start) 213 { 214 return vhost_kernel_call(dev, VHOST_VSOCK_SET_RUNNING, &start); 215 } 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 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 .vhost_vsock_set_guest_cid = vhost_kernel_vsock_set_guest_cid, 321 .vhost_vsock_set_running = vhost_kernel_vsock_set_running, 322 .vhost_set_iotlb_callback = vhost_kernel_set_iotlb_callback, 323 .vhost_send_device_iotlb_msg = vhost_kernel_send_device_iotlb_msg, 324 }; 325 #endif 326 327 int vhost_backend_update_device_iotlb(struct vhost_dev *dev, 328 uint64_t iova, uint64_t uaddr, 329 uint64_t len, 330 IOMMUAccessFlags perm) 331 { 332 struct vhost_iotlb_msg imsg; 333 334 imsg.iova = iova; 335 imsg.uaddr = uaddr; 336 imsg.size = len; 337 imsg.type = VHOST_IOTLB_UPDATE; 338 339 switch (perm) { 340 case IOMMU_RO: 341 imsg.perm = VHOST_ACCESS_RO; 342 break; 343 case IOMMU_WO: 344 imsg.perm = VHOST_ACCESS_WO; 345 break; 346 case IOMMU_RW: 347 imsg.perm = VHOST_ACCESS_RW; 348 break; 349 default: 350 return -EINVAL; 351 } 352 353 if (dev->vhost_ops && dev->vhost_ops->vhost_send_device_iotlb_msg) 354 return dev->vhost_ops->vhost_send_device_iotlb_msg(dev, &imsg); 355 356 return -ENODEV; 357 } 358 359 int vhost_backend_invalidate_device_iotlb(struct vhost_dev *dev, 360 uint64_t iova, uint64_t len) 361 { 362 struct vhost_iotlb_msg imsg; 363 364 imsg.iova = iova; 365 imsg.size = len; 366 imsg.type = VHOST_IOTLB_INVALIDATE; 367 368 if (dev->vhost_ops && dev->vhost_ops->vhost_send_device_iotlb_msg) 369 return dev->vhost_ops->vhost_send_device_iotlb_msg(dev, &imsg); 370 371 return -ENODEV; 372 } 373 374 int vhost_backend_handle_iotlb_msg(struct vhost_dev *dev, 375 struct vhost_iotlb_msg *imsg) 376 { 377 int ret = 0; 378 379 if (unlikely(!dev->vdev)) { 380 error_report("Unexpected IOTLB message when virtio device is stopped"); 381 return -EINVAL; 382 } 383 384 switch (imsg->type) { 385 case VHOST_IOTLB_MISS: 386 ret = vhost_device_iotlb_miss(dev, imsg->iova, 387 imsg->perm != VHOST_ACCESS_RO); 388 break; 389 case VHOST_IOTLB_ACCESS_FAIL: 390 /* FIXME: report device iotlb error */ 391 error_report("Access failure IOTLB message type not supported"); 392 ret = -ENOTSUP; 393 break; 394 case VHOST_IOTLB_UPDATE: 395 case VHOST_IOTLB_INVALIDATE: 396 default: 397 error_report("Unexpected IOTLB message type"); 398 ret = -EINVAL; 399 break; 400 } 401 402 return ret; 403 } 404