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_get_vq_index(struct vhost_dev *dev, int idx) 201 { 202 assert(idx >= dev->vq_index && idx < dev->vq_index + dev->nvqs); 203 204 return idx - dev->vq_index; 205 } 206 207 static int vhost_kernel_vsock_set_guest_cid(struct vhost_dev *dev, 208 uint64_t guest_cid) 209 { 210 return vhost_kernel_call(dev, VHOST_VSOCK_SET_GUEST_CID, &guest_cid); 211 } 212 213 static int vhost_kernel_vsock_set_running(struct vhost_dev *dev, int start) 214 { 215 return vhost_kernel_call(dev, VHOST_VSOCK_SET_RUNNING, &start); 216 } 217 218 static void vhost_kernel_iotlb_read(void *opaque) 219 { 220 struct vhost_dev *dev = opaque; 221 ssize_t len; 222 223 if (dev->backend_cap & 224 (0x1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2)) { 225 struct vhost_msg_v2 msg; 226 227 while ((len = read((uintptr_t)dev->opaque, &msg, sizeof msg)) > 0) { 228 if (len < sizeof msg) { 229 error_report("Wrong vhost message len: %d", (int)len); 230 break; 231 } 232 if (msg.type != VHOST_IOTLB_MSG_V2) { 233 error_report("Unknown vhost iotlb message type"); 234 break; 235 } 236 237 vhost_backend_handle_iotlb_msg(dev, &msg.iotlb); 238 } 239 } else { 240 struct vhost_msg msg; 241 242 while ((len = read((uintptr_t)dev->opaque, &msg, sizeof msg)) > 0) { 243 if (len < sizeof msg) { 244 error_report("Wrong vhost message len: %d", (int)len); 245 break; 246 } 247 if (msg.type != VHOST_IOTLB_MSG) { 248 error_report("Unknown vhost iotlb message type"); 249 break; 250 } 251 252 vhost_backend_handle_iotlb_msg(dev, &msg.iotlb); 253 } 254 } 255 } 256 257 static int vhost_kernel_send_device_iotlb_msg(struct vhost_dev *dev, 258 struct vhost_iotlb_msg *imsg) 259 { 260 if (dev->backend_cap & (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2)) { 261 struct vhost_msg_v2 msg = {}; 262 263 msg.type = VHOST_IOTLB_MSG_V2; 264 msg.iotlb = *imsg; 265 266 if (write((uintptr_t)dev->opaque, &msg, sizeof msg) != sizeof msg) { 267 error_report("Fail to update device iotlb"); 268 return -EFAULT; 269 } 270 } else { 271 struct vhost_msg msg = {}; 272 273 msg.type = VHOST_IOTLB_MSG; 274 msg.iotlb = *imsg; 275 276 if (write((uintptr_t)dev->opaque, &msg, sizeof msg) != sizeof msg) { 277 error_report("Fail to update device iotlb"); 278 return -EFAULT; 279 } 280 } 281 282 return 0; 283 } 284 285 static void vhost_kernel_set_iotlb_callback(struct vhost_dev *dev, 286 int enabled) 287 { 288 if (enabled) 289 qemu_set_fd_handler((uintptr_t)dev->opaque, 290 vhost_kernel_iotlb_read, NULL, dev); 291 else 292 qemu_set_fd_handler((uintptr_t)dev->opaque, NULL, NULL, NULL); 293 } 294 295 const VhostOps kernel_ops = { 296 .backend_type = VHOST_BACKEND_TYPE_KERNEL, 297 .vhost_backend_init = vhost_kernel_init, 298 .vhost_backend_cleanup = vhost_kernel_cleanup, 299 .vhost_backend_memslots_limit = vhost_kernel_memslots_limit, 300 .vhost_net_set_backend = vhost_kernel_net_set_backend, 301 .vhost_scsi_set_endpoint = vhost_kernel_scsi_set_endpoint, 302 .vhost_scsi_clear_endpoint = vhost_kernel_scsi_clear_endpoint, 303 .vhost_scsi_get_abi_version = vhost_kernel_scsi_get_abi_version, 304 .vhost_set_log_base = vhost_kernel_set_log_base, 305 .vhost_set_mem_table = vhost_kernel_set_mem_table, 306 .vhost_set_vring_addr = vhost_kernel_set_vring_addr, 307 .vhost_set_vring_endian = vhost_kernel_set_vring_endian, 308 .vhost_set_vring_num = vhost_kernel_set_vring_num, 309 .vhost_set_vring_base = vhost_kernel_set_vring_base, 310 .vhost_get_vring_base = vhost_kernel_get_vring_base, 311 .vhost_set_vring_kick = vhost_kernel_set_vring_kick, 312 .vhost_set_vring_call = vhost_kernel_set_vring_call, 313 .vhost_set_vring_err = vhost_kernel_set_vring_err, 314 .vhost_set_vring_busyloop_timeout = 315 vhost_kernel_set_vring_busyloop_timeout, 316 .vhost_set_features = vhost_kernel_set_features, 317 .vhost_get_features = vhost_kernel_get_features, 318 .vhost_set_backend_cap = vhost_kernel_set_backend_cap, 319 .vhost_set_owner = vhost_kernel_set_owner, 320 .vhost_get_vq_index = vhost_kernel_get_vq_index, 321 .vhost_vsock_set_guest_cid = vhost_kernel_vsock_set_guest_cid, 322 .vhost_vsock_set_running = vhost_kernel_vsock_set_running, 323 .vhost_set_iotlb_callback = vhost_kernel_set_iotlb_callback, 324 .vhost_send_device_iotlb_msg = vhost_kernel_send_device_iotlb_msg, 325 }; 326 #endif 327 328 int vhost_backend_update_device_iotlb(struct vhost_dev *dev, 329 uint64_t iova, uint64_t uaddr, 330 uint64_t len, 331 IOMMUAccessFlags perm) 332 { 333 struct vhost_iotlb_msg imsg; 334 335 imsg.iova = iova; 336 imsg.uaddr = uaddr; 337 imsg.size = len; 338 imsg.type = VHOST_IOTLB_UPDATE; 339 340 switch (perm) { 341 case IOMMU_RO: 342 imsg.perm = VHOST_ACCESS_RO; 343 break; 344 case IOMMU_WO: 345 imsg.perm = VHOST_ACCESS_WO; 346 break; 347 case IOMMU_RW: 348 imsg.perm = VHOST_ACCESS_RW; 349 break; 350 default: 351 return -EINVAL; 352 } 353 354 if (dev->vhost_ops && dev->vhost_ops->vhost_send_device_iotlb_msg) 355 return dev->vhost_ops->vhost_send_device_iotlb_msg(dev, &imsg); 356 357 return -ENODEV; 358 } 359 360 int vhost_backend_invalidate_device_iotlb(struct vhost_dev *dev, 361 uint64_t iova, uint64_t len) 362 { 363 struct vhost_iotlb_msg imsg; 364 365 imsg.iova = iova; 366 imsg.size = len; 367 imsg.type = VHOST_IOTLB_INVALIDATE; 368 369 if (dev->vhost_ops && dev->vhost_ops->vhost_send_device_iotlb_msg) 370 return dev->vhost_ops->vhost_send_device_iotlb_msg(dev, &imsg); 371 372 return -ENODEV; 373 } 374 375 int vhost_backend_handle_iotlb_msg(struct vhost_dev *dev, 376 struct vhost_iotlb_msg *imsg) 377 { 378 int ret = 0; 379 380 if (unlikely(!dev->vdev)) { 381 error_report("Unexpected IOTLB message when virtio device is stopped"); 382 return -EINVAL; 383 } 384 385 switch (imsg->type) { 386 case VHOST_IOTLB_MISS: 387 ret = vhost_device_iotlb_miss(dev, imsg->iova, 388 imsg->perm != VHOST_ACCESS_RO); 389 break; 390 case VHOST_IOTLB_ACCESS_FAIL: 391 /* FIXME: report device iotlb error */ 392 error_report("Access failure IOTLB message type not supported"); 393 ret = -ENOTSUP; 394 break; 395 case VHOST_IOTLB_UPDATE: 396 case VHOST_IOTLB_INVALIDATE: 397 default: 398 error_report("Unexpected IOTLB message type"); 399 ret = -EINVAL; 400 break; 401 } 402 403 return ret; 404 } 405