1 // SPDX-License-Identifier: GPL-2.0 2 /* Simple test of virtio code, entirely in userpsace. */ 3 #define _GNU_SOURCE 4 #include <sched.h> 5 #include <err.h> 6 #include <linux/kernel.h> 7 #include <linux/err.h> 8 #include <linux/virtio.h> 9 #include <linux/vringh.h> 10 #include <linux/virtio_ring.h> 11 #include <linux/virtio_config.h> 12 #include <linux/uaccess.h> 13 #include <sys/types.h> 14 #include <sys/stat.h> 15 #include <sys/mman.h> 16 #include <sys/wait.h> 17 #include <fcntl.h> 18 19 #define USER_MEM (1024*1024) 20 void *__user_addr_min, *__user_addr_max; 21 void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end; 22 static u64 user_addr_offset; 23 24 #define RINGSIZE 256 25 #define ALIGN 4096 26 27 static bool never_notify_host(struct virtqueue *vq) 28 { 29 abort(); 30 } 31 32 static void never_callback_guest(struct virtqueue *vq) 33 { 34 abort(); 35 } 36 37 static bool getrange_iov(struct vringh *vrh, u64 addr, struct vringh_range *r) 38 { 39 if (addr < (u64)(unsigned long)__user_addr_min - user_addr_offset) 40 return false; 41 if (addr >= (u64)(unsigned long)__user_addr_max - user_addr_offset) 42 return false; 43 44 r->start = (u64)(unsigned long)__user_addr_min - user_addr_offset; 45 r->end_incl = (u64)(unsigned long)__user_addr_max - 1 - user_addr_offset; 46 r->offset = user_addr_offset; 47 return true; 48 } 49 50 /* We return single byte ranges. */ 51 static bool getrange_slow(struct vringh *vrh, u64 addr, struct vringh_range *r) 52 { 53 if (addr < (u64)(unsigned long)__user_addr_min - user_addr_offset) 54 return false; 55 if (addr >= (u64)(unsigned long)__user_addr_max - user_addr_offset) 56 return false; 57 58 r->start = addr; 59 r->end_incl = r->start; 60 r->offset = user_addr_offset; 61 return true; 62 } 63 64 struct guest_virtio_device { 65 struct virtio_device vdev; 66 int to_host_fd; 67 unsigned long notifies; 68 }; 69 70 static bool parallel_notify_host(struct virtqueue *vq) 71 { 72 int rc; 73 struct guest_virtio_device *gvdev; 74 75 gvdev = container_of(vq->vdev, struct guest_virtio_device, vdev); 76 rc = write(gvdev->to_host_fd, "", 1); 77 if (rc < 0) 78 return false; 79 gvdev->notifies++; 80 return true; 81 } 82 83 static bool no_notify_host(struct virtqueue *vq) 84 { 85 return true; 86 } 87 88 #define NUM_XFERS (10000000) 89 90 /* We aim for two "distant" cpus. */ 91 static void find_cpus(unsigned int *first, unsigned int *last) 92 { 93 unsigned int i; 94 95 *first = -1U; 96 *last = 0; 97 for (i = 0; i < 4096; i++) { 98 cpu_set_t set; 99 CPU_ZERO(&set); 100 CPU_SET(i, &set); 101 if (sched_setaffinity(getpid(), sizeof(set), &set) == 0) { 102 if (i < *first) 103 *first = i; 104 if (i > *last) 105 *last = i; 106 } 107 } 108 } 109 110 /* Opencoded version for fast mode */ 111 static inline int vringh_get_head(struct vringh *vrh, u16 *head) 112 { 113 u16 avail_idx, i; 114 int err; 115 116 err = get_user(avail_idx, &vrh->vring.avail->idx); 117 if (err) 118 return err; 119 120 if (vrh->last_avail_idx == avail_idx) 121 return 0; 122 123 /* Only get avail ring entries after they have been exposed by guest. */ 124 virtio_rmb(vrh->weak_barriers); 125 126 i = vrh->last_avail_idx & (vrh->vring.num - 1); 127 128 err = get_user(*head, &vrh->vring.avail->ring[i]); 129 if (err) 130 return err; 131 132 vrh->last_avail_idx++; 133 return 1; 134 } 135 136 static int parallel_test(u64 features, 137 bool (*getrange)(struct vringh *vrh, 138 u64 addr, struct vringh_range *r), 139 bool fast_vringh) 140 { 141 void *host_map, *guest_map; 142 int fd, mapsize, to_guest[2], to_host[2]; 143 unsigned long xfers = 0, notifies = 0, receives = 0; 144 unsigned int first_cpu, last_cpu; 145 cpu_set_t cpu_set; 146 char buf[128]; 147 148 /* Create real file to mmap. */ 149 fd = open("/tmp/vringh_test-file", O_RDWR|O_CREAT|O_TRUNC, 0600); 150 if (fd < 0) 151 err(1, "Opening /tmp/vringh_test-file"); 152 153 /* Extra room at the end for some data, and indirects */ 154 mapsize = vring_size(RINGSIZE, ALIGN) 155 + RINGSIZE * 2 * sizeof(int) 156 + RINGSIZE * 6 * sizeof(struct vring_desc); 157 mapsize = (mapsize + getpagesize() - 1) & ~(getpagesize() - 1); 158 ftruncate(fd, mapsize); 159 160 /* Parent and child use separate addresses, to check our mapping logic! */ 161 host_map = mmap(NULL, mapsize, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); 162 guest_map = mmap(NULL, mapsize, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); 163 164 pipe(to_guest); 165 pipe(to_host); 166 167 CPU_ZERO(&cpu_set); 168 find_cpus(&first_cpu, &last_cpu); 169 printf("Using CPUS %u and %u\n", first_cpu, last_cpu); 170 fflush(stdout); 171 172 if (fork() != 0) { 173 struct vringh vrh; 174 int status, err, rlen = 0; 175 char rbuf[5]; 176 177 /* We are the host: never access guest addresses! */ 178 munmap(guest_map, mapsize); 179 180 __user_addr_min = host_map; 181 __user_addr_max = __user_addr_min + mapsize; 182 user_addr_offset = host_map - guest_map; 183 assert(user_addr_offset); 184 185 close(to_guest[0]); 186 close(to_host[1]); 187 188 vring_init(&vrh.vring, RINGSIZE, host_map, ALIGN); 189 vringh_init_user(&vrh, features, RINGSIZE, true, 190 vrh.vring.desc, vrh.vring.avail, vrh.vring.used); 191 CPU_SET(first_cpu, &cpu_set); 192 if (sched_setaffinity(getpid(), sizeof(cpu_set), &cpu_set)) 193 errx(1, "Could not set affinity to cpu %u", first_cpu); 194 195 while (xfers < NUM_XFERS) { 196 struct iovec host_riov[2], host_wiov[2]; 197 struct vringh_iov riov, wiov; 198 u16 head, written; 199 200 if (fast_vringh) { 201 for (;;) { 202 err = vringh_get_head(&vrh, &head); 203 if (err != 0) 204 break; 205 err = vringh_need_notify_user(&vrh); 206 if (err < 0) 207 errx(1, "vringh_need_notify_user: %i", 208 err); 209 if (err) { 210 write(to_guest[1], "", 1); 211 notifies++; 212 } 213 } 214 if (err != 1) 215 errx(1, "vringh_get_head"); 216 written = 0; 217 goto complete; 218 } else { 219 vringh_iov_init(&riov, 220 host_riov, 221 ARRAY_SIZE(host_riov)); 222 vringh_iov_init(&wiov, 223 host_wiov, 224 ARRAY_SIZE(host_wiov)); 225 226 err = vringh_getdesc_user(&vrh, &riov, &wiov, 227 getrange, &head); 228 } 229 if (err == 0) { 230 err = vringh_need_notify_user(&vrh); 231 if (err < 0) 232 errx(1, "vringh_need_notify_user: %i", 233 err); 234 if (err) { 235 write(to_guest[1], "", 1); 236 notifies++; 237 } 238 239 if (!vringh_notify_enable_user(&vrh)) 240 continue; 241 242 /* Swallow all notifies at once. */ 243 if (read(to_host[0], buf, sizeof(buf)) < 1) 244 break; 245 246 vringh_notify_disable_user(&vrh); 247 receives++; 248 continue; 249 } 250 if (err != 1) 251 errx(1, "vringh_getdesc_user: %i", err); 252 253 /* We simply copy bytes. */ 254 if (riov.used) { 255 rlen = vringh_iov_pull_user(&riov, rbuf, 256 sizeof(rbuf)); 257 if (rlen != 4) 258 errx(1, "vringh_iov_pull_user: %i", 259 rlen); 260 assert(riov.i == riov.used); 261 written = 0; 262 } else { 263 err = vringh_iov_push_user(&wiov, rbuf, rlen); 264 if (err != rlen) 265 errx(1, "vringh_iov_push_user: %i", 266 err); 267 assert(wiov.i == wiov.used); 268 written = err; 269 } 270 complete: 271 xfers++; 272 273 err = vringh_complete_user(&vrh, head, written); 274 if (err != 0) 275 errx(1, "vringh_complete_user: %i", err); 276 } 277 278 err = vringh_need_notify_user(&vrh); 279 if (err < 0) 280 errx(1, "vringh_need_notify_user: %i", err); 281 if (err) { 282 write(to_guest[1], "", 1); 283 notifies++; 284 } 285 wait(&status); 286 if (!WIFEXITED(status)) 287 errx(1, "Child died with signal %i?", WTERMSIG(status)); 288 if (WEXITSTATUS(status) != 0) 289 errx(1, "Child exited %i?", WEXITSTATUS(status)); 290 printf("Host: notified %lu, pinged %lu\n", notifies, receives); 291 return 0; 292 } else { 293 struct guest_virtio_device gvdev; 294 struct virtqueue *vq; 295 unsigned int *data; 296 struct vring_desc *indirects; 297 unsigned int finished = 0; 298 299 /* We pass sg[]s pointing into here, but we need RINGSIZE+1 */ 300 data = guest_map + vring_size(RINGSIZE, ALIGN); 301 indirects = (void *)data + (RINGSIZE + 1) * 2 * sizeof(int); 302 303 /* We are the guest. */ 304 munmap(host_map, mapsize); 305 306 close(to_guest[1]); 307 close(to_host[0]); 308 309 gvdev.vdev.features = features; 310 INIT_LIST_HEAD(&gvdev.vdev.vqs); 311 gvdev.to_host_fd = to_host[1]; 312 gvdev.notifies = 0; 313 314 CPU_SET(first_cpu, &cpu_set); 315 if (sched_setaffinity(getpid(), sizeof(cpu_set), &cpu_set)) 316 err(1, "Could not set affinity to cpu %u", first_cpu); 317 318 vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &gvdev.vdev, true, 319 false, guest_map, 320 fast_vringh ? no_notify_host 321 : parallel_notify_host, 322 never_callback_guest, "guest vq"); 323 324 /* Don't kfree indirects. */ 325 __kfree_ignore_start = indirects; 326 __kfree_ignore_end = indirects + RINGSIZE * 6; 327 328 while (xfers < NUM_XFERS) { 329 struct scatterlist sg[4]; 330 unsigned int num_sg, len; 331 int *dbuf, err; 332 bool output = !(xfers % 2); 333 334 /* Consume bufs. */ 335 while ((dbuf = virtqueue_get_buf(vq, &len)) != NULL) { 336 if (len == 4) 337 assert(*dbuf == finished - 1); 338 else if (!fast_vringh) 339 assert(*dbuf == finished); 340 finished++; 341 } 342 343 /* Produce a buffer. */ 344 dbuf = data + (xfers % (RINGSIZE + 1)); 345 346 if (output) 347 *dbuf = xfers; 348 else 349 *dbuf = -1; 350 351 switch ((xfers / sizeof(*dbuf)) % 4) { 352 case 0: 353 /* Nasty three-element sg list. */ 354 sg_init_table(sg, num_sg = 3); 355 sg_set_buf(&sg[0], (void *)dbuf, 1); 356 sg_set_buf(&sg[1], (void *)dbuf + 1, 2); 357 sg_set_buf(&sg[2], (void *)dbuf + 3, 1); 358 break; 359 case 1: 360 sg_init_table(sg, num_sg = 2); 361 sg_set_buf(&sg[0], (void *)dbuf, 1); 362 sg_set_buf(&sg[1], (void *)dbuf + 1, 3); 363 break; 364 case 2: 365 sg_init_table(sg, num_sg = 1); 366 sg_set_buf(&sg[0], (void *)dbuf, 4); 367 break; 368 case 3: 369 sg_init_table(sg, num_sg = 4); 370 sg_set_buf(&sg[0], (void *)dbuf, 1); 371 sg_set_buf(&sg[1], (void *)dbuf + 1, 1); 372 sg_set_buf(&sg[2], (void *)dbuf + 2, 1); 373 sg_set_buf(&sg[3], (void *)dbuf + 3, 1); 374 break; 375 } 376 377 /* May allocate an indirect, so force it to allocate 378 * user addr */ 379 __kmalloc_fake = indirects + (xfers % RINGSIZE) * 4; 380 if (output) 381 err = virtqueue_add_outbuf(vq, sg, num_sg, dbuf, 382 GFP_KERNEL); 383 else 384 err = virtqueue_add_inbuf(vq, sg, num_sg, 385 dbuf, GFP_KERNEL); 386 387 if (err == -ENOSPC) { 388 if (!virtqueue_enable_cb_delayed(vq)) 389 continue; 390 /* Swallow all notifies at once. */ 391 if (read(to_guest[0], buf, sizeof(buf)) < 1) 392 break; 393 394 receives++; 395 virtqueue_disable_cb(vq); 396 continue; 397 } 398 399 if (err) 400 errx(1, "virtqueue_add_in/outbuf: %i", err); 401 402 xfers++; 403 virtqueue_kick(vq); 404 } 405 406 /* Any extra? */ 407 while (finished != xfers) { 408 int *dbuf; 409 unsigned int len; 410 411 /* Consume bufs. */ 412 dbuf = virtqueue_get_buf(vq, &len); 413 if (dbuf) { 414 if (len == 4) 415 assert(*dbuf == finished - 1); 416 else 417 assert(len == 0); 418 finished++; 419 continue; 420 } 421 422 if (!virtqueue_enable_cb_delayed(vq)) 423 continue; 424 if (read(to_guest[0], buf, sizeof(buf)) < 1) 425 break; 426 427 receives++; 428 virtqueue_disable_cb(vq); 429 } 430 431 printf("Guest: notified %lu, pinged %lu\n", 432 gvdev.notifies, receives); 433 vring_del_virtqueue(vq); 434 return 0; 435 } 436 } 437 438 int main(int argc, char *argv[]) 439 { 440 struct virtio_device vdev; 441 struct virtqueue *vq; 442 struct vringh vrh; 443 struct scatterlist guest_sg[RINGSIZE], *sgs[2]; 444 struct iovec host_riov[2], host_wiov[2]; 445 struct vringh_iov riov, wiov; 446 struct vring_used_elem used[RINGSIZE]; 447 char buf[28]; 448 u16 head; 449 int err; 450 unsigned i; 451 void *ret; 452 bool (*getrange)(struct vringh *vrh, u64 addr, struct vringh_range *r); 453 bool fast_vringh = false, parallel = false; 454 455 getrange = getrange_iov; 456 vdev.features = 0; 457 INIT_LIST_HEAD(&vdev.vqs); 458 459 while (argv[1]) { 460 if (strcmp(argv[1], "--indirect") == 0) 461 __virtio_set_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC); 462 else if (strcmp(argv[1], "--eventidx") == 0) 463 __virtio_set_bit(&vdev, VIRTIO_RING_F_EVENT_IDX); 464 else if (strcmp(argv[1], "--virtio-1") == 0) 465 __virtio_set_bit(&vdev, VIRTIO_F_VERSION_1); 466 else if (strcmp(argv[1], "--slow-range") == 0) 467 getrange = getrange_slow; 468 else if (strcmp(argv[1], "--fast-vringh") == 0) 469 fast_vringh = true; 470 else if (strcmp(argv[1], "--parallel") == 0) 471 parallel = true; 472 else 473 errx(1, "Unknown arg %s", argv[1]); 474 argv++; 475 } 476 477 if (parallel) 478 return parallel_test(vdev.features, getrange, fast_vringh); 479 480 if (posix_memalign(&__user_addr_min, PAGE_SIZE, USER_MEM) != 0) 481 abort(); 482 __user_addr_max = __user_addr_min + USER_MEM; 483 memset(__user_addr_min, 0, vring_size(RINGSIZE, ALIGN)); 484 485 /* Set up guest side. */ 486 vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &vdev, true, false, 487 __user_addr_min, 488 never_notify_host, never_callback_guest, 489 "guest vq"); 490 491 /* Set up host side. */ 492 vring_init(&vrh.vring, RINGSIZE, __user_addr_min, ALIGN); 493 vringh_init_user(&vrh, vdev.features, RINGSIZE, true, 494 vrh.vring.desc, vrh.vring.avail, vrh.vring.used); 495 496 /* No descriptor to get yet... */ 497 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head); 498 if (err != 0) 499 errx(1, "vringh_getdesc_user: %i", err); 500 501 /* Guest puts in a descriptor. */ 502 memcpy(__user_addr_max - 1, "a", 1); 503 sg_init_table(guest_sg, 1); 504 sg_set_buf(&guest_sg[0], __user_addr_max - 1, 1); 505 sg_init_table(guest_sg+1, 1); 506 sg_set_buf(&guest_sg[1], __user_addr_max - 3, 2); 507 sgs[0] = &guest_sg[0]; 508 sgs[1] = &guest_sg[1]; 509 510 /* May allocate an indirect, so force it to allocate user addr */ 511 __kmalloc_fake = __user_addr_min + vring_size(RINGSIZE, ALIGN); 512 err = virtqueue_add_sgs(vq, sgs, 1, 1, &err, GFP_KERNEL); 513 if (err) 514 errx(1, "virtqueue_add_sgs: %i", err); 515 __kmalloc_fake = NULL; 516 517 /* Host retreives it. */ 518 vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov)); 519 vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov)); 520 521 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head); 522 if (err != 1) 523 errx(1, "vringh_getdesc_user: %i", err); 524 525 assert(riov.used == 1); 526 assert(riov.iov[0].iov_base == __user_addr_max - 1); 527 assert(riov.iov[0].iov_len == 1); 528 if (getrange != getrange_slow) { 529 assert(wiov.used == 1); 530 assert(wiov.iov[0].iov_base == __user_addr_max - 3); 531 assert(wiov.iov[0].iov_len == 2); 532 } else { 533 assert(wiov.used == 2); 534 assert(wiov.iov[0].iov_base == __user_addr_max - 3); 535 assert(wiov.iov[0].iov_len == 1); 536 assert(wiov.iov[1].iov_base == __user_addr_max - 2); 537 assert(wiov.iov[1].iov_len == 1); 538 } 539 540 err = vringh_iov_pull_user(&riov, buf, 5); 541 if (err != 1) 542 errx(1, "vringh_iov_pull_user: %i", err); 543 assert(buf[0] == 'a'); 544 assert(riov.i == 1); 545 assert(vringh_iov_pull_user(&riov, buf, 5) == 0); 546 547 memcpy(buf, "bcdef", 5); 548 err = vringh_iov_push_user(&wiov, buf, 5); 549 if (err != 2) 550 errx(1, "vringh_iov_push_user: %i", err); 551 assert(memcmp(__user_addr_max - 3, "bc", 2) == 0); 552 assert(wiov.i == wiov.used); 553 assert(vringh_iov_push_user(&wiov, buf, 5) == 0); 554 555 /* Host is done. */ 556 err = vringh_complete_user(&vrh, head, err); 557 if (err != 0) 558 errx(1, "vringh_complete_user: %i", err); 559 560 /* Guest should see used token now. */ 561 __kfree_ignore_start = __user_addr_min + vring_size(RINGSIZE, ALIGN); 562 __kfree_ignore_end = __kfree_ignore_start + 1; 563 ret = virtqueue_get_buf(vq, &i); 564 if (ret != &err) 565 errx(1, "virtqueue_get_buf: %p", ret); 566 assert(i == 2); 567 568 /* Guest puts in a huge descriptor. */ 569 sg_init_table(guest_sg, RINGSIZE); 570 for (i = 0; i < RINGSIZE; i++) { 571 sg_set_buf(&guest_sg[i], 572 __user_addr_max - USER_MEM/4, USER_MEM/4); 573 } 574 575 /* Fill contents with recognisable garbage. */ 576 for (i = 0; i < USER_MEM/4; i++) 577 ((char *)__user_addr_max - USER_MEM/4)[i] = i; 578 579 /* This will allocate an indirect, so force it to allocate user addr */ 580 __kmalloc_fake = __user_addr_min + vring_size(RINGSIZE, ALIGN); 581 err = virtqueue_add_outbuf(vq, guest_sg, RINGSIZE, &err, GFP_KERNEL); 582 if (err) 583 errx(1, "virtqueue_add_outbuf (large): %i", err); 584 __kmalloc_fake = NULL; 585 586 /* Host picks it up (allocates new iov). */ 587 vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov)); 588 vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov)); 589 590 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head); 591 if (err != 1) 592 errx(1, "vringh_getdesc_user: %i", err); 593 594 assert(riov.max_num & VRINGH_IOV_ALLOCATED); 595 assert(riov.iov != host_riov); 596 if (getrange != getrange_slow) 597 assert(riov.used == RINGSIZE); 598 else 599 assert(riov.used == RINGSIZE * USER_MEM/4); 600 601 assert(!(wiov.max_num & VRINGH_IOV_ALLOCATED)); 602 assert(wiov.used == 0); 603 604 /* Pull data back out (in odd chunks), should be as expected. */ 605 for (i = 0; i < RINGSIZE * USER_MEM/4; i += 3) { 606 err = vringh_iov_pull_user(&riov, buf, 3); 607 if (err != 3 && i + err != RINGSIZE * USER_MEM/4) 608 errx(1, "vringh_iov_pull_user large: %i", err); 609 assert(buf[0] == (char)i); 610 assert(err < 2 || buf[1] == (char)(i + 1)); 611 assert(err < 3 || buf[2] == (char)(i + 2)); 612 } 613 assert(riov.i == riov.used); 614 vringh_iov_cleanup(&riov); 615 vringh_iov_cleanup(&wiov); 616 617 /* Complete using multi interface, just because we can. */ 618 used[0].id = head; 619 used[0].len = 0; 620 err = vringh_complete_multi_user(&vrh, used, 1); 621 if (err) 622 errx(1, "vringh_complete_multi_user(1): %i", err); 623 624 /* Free up those descriptors. */ 625 ret = virtqueue_get_buf(vq, &i); 626 if (ret != &err) 627 errx(1, "virtqueue_get_buf: %p", ret); 628 629 /* Add lots of descriptors. */ 630 sg_init_table(guest_sg, 1); 631 sg_set_buf(&guest_sg[0], __user_addr_max - 1, 1); 632 for (i = 0; i < RINGSIZE; i++) { 633 err = virtqueue_add_outbuf(vq, guest_sg, 1, &err, GFP_KERNEL); 634 if (err) 635 errx(1, "virtqueue_add_outbuf (multiple): %i", err); 636 } 637 638 /* Now get many, and consume them all at once. */ 639 vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov)); 640 vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov)); 641 642 for (i = 0; i < RINGSIZE; i++) { 643 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head); 644 if (err != 1) 645 errx(1, "vringh_getdesc_user: %i", err); 646 used[i].id = head; 647 used[i].len = 0; 648 } 649 /* Make sure it wraps around ring, to test! */ 650 assert(vrh.vring.used->idx % RINGSIZE != 0); 651 err = vringh_complete_multi_user(&vrh, used, RINGSIZE); 652 if (err) 653 errx(1, "vringh_complete_multi_user: %i", err); 654 655 /* Free those buffers. */ 656 for (i = 0; i < RINGSIZE; i++) { 657 unsigned len; 658 assert(virtqueue_get_buf(vq, &len) != NULL); 659 } 660 661 /* Test weird (but legal!) indirect. */ 662 if (__virtio_test_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC)) { 663 char *data = __user_addr_max - USER_MEM/4; 664 struct vring_desc *d = __user_addr_max - USER_MEM/2; 665 struct vring vring; 666 667 /* Force creation of direct, which we modify. */ 668 __virtio_clear_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC); 669 vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &vdev, true, 670 false, __user_addr_min, 671 never_notify_host, 672 never_callback_guest, 673 "guest vq"); 674 675 sg_init_table(guest_sg, 4); 676 sg_set_buf(&guest_sg[0], d, sizeof(*d)*2); 677 sg_set_buf(&guest_sg[1], d + 2, sizeof(*d)*1); 678 sg_set_buf(&guest_sg[2], data + 6, 4); 679 sg_set_buf(&guest_sg[3], d + 3, sizeof(*d)*3); 680 681 err = virtqueue_add_outbuf(vq, guest_sg, 4, &err, GFP_KERNEL); 682 if (err) 683 errx(1, "virtqueue_add_outbuf (indirect): %i", err); 684 685 vring_init(&vring, RINGSIZE, __user_addr_min, ALIGN); 686 687 /* They're used in order, but double-check... */ 688 assert(vring.desc[0].addr == (unsigned long)d); 689 assert(vring.desc[1].addr == (unsigned long)(d+2)); 690 assert(vring.desc[2].addr == (unsigned long)data + 6); 691 assert(vring.desc[3].addr == (unsigned long)(d+3)); 692 vring.desc[0].flags |= VRING_DESC_F_INDIRECT; 693 vring.desc[1].flags |= VRING_DESC_F_INDIRECT; 694 vring.desc[3].flags |= VRING_DESC_F_INDIRECT; 695 696 /* First indirect */ 697 d[0].addr = (unsigned long)data; 698 d[0].len = 1; 699 d[0].flags = VRING_DESC_F_NEXT; 700 d[0].next = 1; 701 d[1].addr = (unsigned long)data + 1; 702 d[1].len = 2; 703 d[1].flags = 0; 704 705 /* Second indirect */ 706 d[2].addr = (unsigned long)data + 3; 707 d[2].len = 3; 708 d[2].flags = 0; 709 710 /* Third indirect */ 711 d[3].addr = (unsigned long)data + 10; 712 d[3].len = 5; 713 d[3].flags = VRING_DESC_F_NEXT; 714 d[3].next = 1; 715 d[4].addr = (unsigned long)data + 15; 716 d[4].len = 6; 717 d[4].flags = VRING_DESC_F_NEXT; 718 d[4].next = 2; 719 d[5].addr = (unsigned long)data + 21; 720 d[5].len = 7; 721 d[5].flags = 0; 722 723 /* Host picks it up (allocates new iov). */ 724 vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov)); 725 vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov)); 726 727 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head); 728 if (err != 1) 729 errx(1, "vringh_getdesc_user: %i", err); 730 731 if (head != 0) 732 errx(1, "vringh_getdesc_user: head %i not 0", head); 733 734 assert(riov.max_num & VRINGH_IOV_ALLOCATED); 735 if (getrange != getrange_slow) 736 assert(riov.used == 7); 737 else 738 assert(riov.used == 28); 739 err = vringh_iov_pull_user(&riov, buf, 29); 740 assert(err == 28); 741 742 /* Data should be linear. */ 743 for (i = 0; i < err; i++) 744 assert(buf[i] == i); 745 vringh_iov_cleanup(&riov); 746 } 747 748 /* Don't leak memory... */ 749 vring_del_virtqueue(vq); 750 free(__user_addr_min); 751 752 return 0; 753 } 754