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 pipe_ret, 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_ret = pipe(to_guest); 165 assert(!pipe_ret); 166 167 pipe_ret = pipe(to_host); 168 assert(!pipe_ret); 169 170 CPU_ZERO(&cpu_set); 171 find_cpus(&first_cpu, &last_cpu); 172 printf("Using CPUS %u and %u\n", first_cpu, last_cpu); 173 fflush(stdout); 174 175 if (fork() != 0) { 176 struct vringh vrh; 177 int status, err, rlen = 0; 178 char rbuf[5]; 179 180 /* We are the host: never access guest addresses! */ 181 munmap(guest_map, mapsize); 182 183 __user_addr_min = host_map; 184 __user_addr_max = __user_addr_min + mapsize; 185 user_addr_offset = host_map - guest_map; 186 assert(user_addr_offset); 187 188 close(to_guest[0]); 189 close(to_host[1]); 190 191 vring_init(&vrh.vring, RINGSIZE, host_map, ALIGN); 192 vringh_init_user(&vrh, features, RINGSIZE, true, 193 vrh.vring.desc, vrh.vring.avail, vrh.vring.used); 194 CPU_SET(first_cpu, &cpu_set); 195 if (sched_setaffinity(getpid(), sizeof(cpu_set), &cpu_set)) 196 errx(1, "Could not set affinity to cpu %u", first_cpu); 197 198 while (xfers < NUM_XFERS) { 199 struct iovec host_riov[2], host_wiov[2]; 200 struct vringh_iov riov, wiov; 201 u16 head, written; 202 203 if (fast_vringh) { 204 for (;;) { 205 err = vringh_get_head(&vrh, &head); 206 if (err != 0) 207 break; 208 err = vringh_need_notify_user(&vrh); 209 if (err < 0) 210 errx(1, "vringh_need_notify_user: %i", 211 err); 212 if (err) { 213 write(to_guest[1], "", 1); 214 notifies++; 215 } 216 } 217 if (err != 1) 218 errx(1, "vringh_get_head"); 219 written = 0; 220 goto complete; 221 } else { 222 vringh_iov_init(&riov, 223 host_riov, 224 ARRAY_SIZE(host_riov)); 225 vringh_iov_init(&wiov, 226 host_wiov, 227 ARRAY_SIZE(host_wiov)); 228 229 err = vringh_getdesc_user(&vrh, &riov, &wiov, 230 getrange, &head); 231 } 232 if (err == 0) { 233 err = vringh_need_notify_user(&vrh); 234 if (err < 0) 235 errx(1, "vringh_need_notify_user: %i", 236 err); 237 if (err) { 238 write(to_guest[1], "", 1); 239 notifies++; 240 } 241 242 if (!vringh_notify_enable_user(&vrh)) 243 continue; 244 245 /* Swallow all notifies at once. */ 246 if (read(to_host[0], buf, sizeof(buf)) < 1) 247 break; 248 249 vringh_notify_disable_user(&vrh); 250 receives++; 251 continue; 252 } 253 if (err != 1) 254 errx(1, "vringh_getdesc_user: %i", err); 255 256 /* We simply copy bytes. */ 257 if (riov.used) { 258 rlen = vringh_iov_pull_user(&riov, rbuf, 259 sizeof(rbuf)); 260 if (rlen != 4) 261 errx(1, "vringh_iov_pull_user: %i", 262 rlen); 263 assert(riov.i == riov.used); 264 written = 0; 265 } else { 266 err = vringh_iov_push_user(&wiov, rbuf, rlen); 267 if (err != rlen) 268 errx(1, "vringh_iov_push_user: %i", 269 err); 270 assert(wiov.i == wiov.used); 271 written = err; 272 } 273 complete: 274 xfers++; 275 276 err = vringh_complete_user(&vrh, head, written); 277 if (err != 0) 278 errx(1, "vringh_complete_user: %i", err); 279 } 280 281 err = vringh_need_notify_user(&vrh); 282 if (err < 0) 283 errx(1, "vringh_need_notify_user: %i", err); 284 if (err) { 285 write(to_guest[1], "", 1); 286 notifies++; 287 } 288 wait(&status); 289 if (!WIFEXITED(status)) 290 errx(1, "Child died with signal %i?", WTERMSIG(status)); 291 if (WEXITSTATUS(status) != 0) 292 errx(1, "Child exited %i?", WEXITSTATUS(status)); 293 printf("Host: notified %lu, pinged %lu\n", notifies, receives); 294 return 0; 295 } else { 296 struct guest_virtio_device gvdev; 297 struct virtqueue *vq; 298 unsigned int *data; 299 struct vring_desc *indirects; 300 unsigned int finished = 0; 301 302 /* We pass sg[]s pointing into here, but we need RINGSIZE+1 */ 303 data = guest_map + vring_size(RINGSIZE, ALIGN); 304 indirects = (void *)data + (RINGSIZE + 1) * 2 * sizeof(int); 305 306 /* We are the guest. */ 307 munmap(host_map, mapsize); 308 309 close(to_guest[1]); 310 close(to_host[0]); 311 312 gvdev.vdev.features = features; 313 INIT_LIST_HEAD(&gvdev.vdev.vqs); 314 spin_lock_init(&gvdev.vdev.vqs_list_lock); 315 gvdev.to_host_fd = to_host[1]; 316 gvdev.notifies = 0; 317 318 CPU_SET(first_cpu, &cpu_set); 319 if (sched_setaffinity(getpid(), sizeof(cpu_set), &cpu_set)) 320 err(1, "Could not set affinity to cpu %u", first_cpu); 321 322 vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &gvdev.vdev, true, 323 false, guest_map, 324 fast_vringh ? no_notify_host 325 : parallel_notify_host, 326 never_callback_guest, "guest vq"); 327 328 /* Don't kfree indirects. */ 329 __kfree_ignore_start = indirects; 330 __kfree_ignore_end = indirects + RINGSIZE * 6; 331 332 while (xfers < NUM_XFERS) { 333 struct scatterlist sg[4]; 334 unsigned int num_sg, len; 335 int *dbuf, err; 336 bool output = !(xfers % 2); 337 338 /* Consume bufs. */ 339 while ((dbuf = virtqueue_get_buf(vq, &len)) != NULL) { 340 if (len == 4) 341 assert(*dbuf == finished - 1); 342 else if (!fast_vringh) 343 assert(*dbuf == finished); 344 finished++; 345 } 346 347 /* Produce a buffer. */ 348 dbuf = data + (xfers % (RINGSIZE + 1)); 349 350 if (output) 351 *dbuf = xfers; 352 else 353 *dbuf = -1; 354 355 switch ((xfers / sizeof(*dbuf)) % 4) { 356 case 0: 357 /* Nasty three-element sg list. */ 358 sg_init_table(sg, num_sg = 3); 359 sg_set_buf(&sg[0], (void *)dbuf, 1); 360 sg_set_buf(&sg[1], (void *)dbuf + 1, 2); 361 sg_set_buf(&sg[2], (void *)dbuf + 3, 1); 362 break; 363 case 1: 364 sg_init_table(sg, num_sg = 2); 365 sg_set_buf(&sg[0], (void *)dbuf, 1); 366 sg_set_buf(&sg[1], (void *)dbuf + 1, 3); 367 break; 368 case 2: 369 sg_init_table(sg, num_sg = 1); 370 sg_set_buf(&sg[0], (void *)dbuf, 4); 371 break; 372 case 3: 373 sg_init_table(sg, num_sg = 4); 374 sg_set_buf(&sg[0], (void *)dbuf, 1); 375 sg_set_buf(&sg[1], (void *)dbuf + 1, 1); 376 sg_set_buf(&sg[2], (void *)dbuf + 2, 1); 377 sg_set_buf(&sg[3], (void *)dbuf + 3, 1); 378 break; 379 } 380 381 /* May allocate an indirect, so force it to allocate 382 * user addr */ 383 __kmalloc_fake = indirects + (xfers % RINGSIZE) * 4; 384 if (output) 385 err = virtqueue_add_outbuf(vq, sg, num_sg, dbuf, 386 GFP_KERNEL); 387 else 388 err = virtqueue_add_inbuf(vq, sg, num_sg, 389 dbuf, GFP_KERNEL); 390 391 if (err == -ENOSPC) { 392 if (!virtqueue_enable_cb_delayed(vq)) 393 continue; 394 /* Swallow all notifies at once. */ 395 if (read(to_guest[0], buf, sizeof(buf)) < 1) 396 break; 397 398 receives++; 399 virtqueue_disable_cb(vq); 400 continue; 401 } 402 403 if (err) 404 errx(1, "virtqueue_add_in/outbuf: %i", err); 405 406 xfers++; 407 virtqueue_kick(vq); 408 } 409 410 /* Any extra? */ 411 while (finished != xfers) { 412 int *dbuf; 413 unsigned int len; 414 415 /* Consume bufs. */ 416 dbuf = virtqueue_get_buf(vq, &len); 417 if (dbuf) { 418 if (len == 4) 419 assert(*dbuf == finished - 1); 420 else 421 assert(len == 0); 422 finished++; 423 continue; 424 } 425 426 if (!virtqueue_enable_cb_delayed(vq)) 427 continue; 428 if (read(to_guest[0], buf, sizeof(buf)) < 1) 429 break; 430 431 receives++; 432 virtqueue_disable_cb(vq); 433 } 434 435 printf("Guest: notified %lu, pinged %lu\n", 436 gvdev.notifies, receives); 437 vring_del_virtqueue(vq); 438 return 0; 439 } 440 } 441 442 int main(int argc, char *argv[]) 443 { 444 struct virtio_device vdev; 445 struct virtqueue *vq; 446 struct vringh vrh; 447 struct scatterlist guest_sg[RINGSIZE], *sgs[2]; 448 struct iovec host_riov[2], host_wiov[2]; 449 struct vringh_iov riov, wiov; 450 struct vring_used_elem used[RINGSIZE]; 451 char buf[28]; 452 u16 head; 453 int err; 454 unsigned i; 455 void *ret; 456 bool (*getrange)(struct vringh *vrh, u64 addr, struct vringh_range *r); 457 bool fast_vringh = false, parallel = false; 458 459 getrange = getrange_iov; 460 vdev.features = 0; 461 INIT_LIST_HEAD(&vdev.vqs); 462 spin_lock_init(&vdev.vqs_list_lock); 463 464 while (argv[1]) { 465 if (strcmp(argv[1], "--indirect") == 0) 466 __virtio_set_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC); 467 else if (strcmp(argv[1], "--eventidx") == 0) 468 __virtio_set_bit(&vdev, VIRTIO_RING_F_EVENT_IDX); 469 else if (strcmp(argv[1], "--virtio-1") == 0) 470 __virtio_set_bit(&vdev, VIRTIO_F_VERSION_1); 471 else if (strcmp(argv[1], "--slow-range") == 0) 472 getrange = getrange_slow; 473 else if (strcmp(argv[1], "--fast-vringh") == 0) 474 fast_vringh = true; 475 else if (strcmp(argv[1], "--parallel") == 0) 476 parallel = true; 477 else 478 errx(1, "Unknown arg %s", argv[1]); 479 argv++; 480 } 481 482 if (parallel) 483 return parallel_test(vdev.features, getrange, fast_vringh); 484 485 if (posix_memalign(&__user_addr_min, PAGE_SIZE, USER_MEM) != 0) 486 abort(); 487 __user_addr_max = __user_addr_min + USER_MEM; 488 memset(__user_addr_min, 0, vring_size(RINGSIZE, ALIGN)); 489 490 /* Set up guest side. */ 491 vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &vdev, true, false, 492 __user_addr_min, 493 never_notify_host, never_callback_guest, 494 "guest vq"); 495 496 /* Set up host side. */ 497 vring_init(&vrh.vring, RINGSIZE, __user_addr_min, ALIGN); 498 vringh_init_user(&vrh, vdev.features, RINGSIZE, true, 499 vrh.vring.desc, vrh.vring.avail, vrh.vring.used); 500 501 /* No descriptor to get yet... */ 502 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head); 503 if (err != 0) 504 errx(1, "vringh_getdesc_user: %i", err); 505 506 /* Guest puts in a descriptor. */ 507 memcpy(__user_addr_max - 1, "a", 1); 508 sg_init_table(guest_sg, 1); 509 sg_set_buf(&guest_sg[0], __user_addr_max - 1, 1); 510 sg_init_table(guest_sg+1, 1); 511 sg_set_buf(&guest_sg[1], __user_addr_max - 3, 2); 512 sgs[0] = &guest_sg[0]; 513 sgs[1] = &guest_sg[1]; 514 515 /* May allocate an indirect, so force it to allocate user addr */ 516 __kmalloc_fake = __user_addr_min + vring_size(RINGSIZE, ALIGN); 517 err = virtqueue_add_sgs(vq, sgs, 1, 1, &err, GFP_KERNEL); 518 if (err) 519 errx(1, "virtqueue_add_sgs: %i", err); 520 __kmalloc_fake = NULL; 521 522 /* Host retreives it. */ 523 vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov)); 524 vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov)); 525 526 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head); 527 if (err != 1) 528 errx(1, "vringh_getdesc_user: %i", err); 529 530 assert(riov.used == 1); 531 assert(riov.iov[0].iov_base == __user_addr_max - 1); 532 assert(riov.iov[0].iov_len == 1); 533 if (getrange != getrange_slow) { 534 assert(wiov.used == 1); 535 assert(wiov.iov[0].iov_base == __user_addr_max - 3); 536 assert(wiov.iov[0].iov_len == 2); 537 } else { 538 assert(wiov.used == 2); 539 assert(wiov.iov[0].iov_base == __user_addr_max - 3); 540 assert(wiov.iov[0].iov_len == 1); 541 assert(wiov.iov[1].iov_base == __user_addr_max - 2); 542 assert(wiov.iov[1].iov_len == 1); 543 } 544 545 err = vringh_iov_pull_user(&riov, buf, 5); 546 if (err != 1) 547 errx(1, "vringh_iov_pull_user: %i", err); 548 assert(buf[0] == 'a'); 549 assert(riov.i == 1); 550 assert(vringh_iov_pull_user(&riov, buf, 5) == 0); 551 552 memcpy(buf, "bcdef", 5); 553 err = vringh_iov_push_user(&wiov, buf, 5); 554 if (err != 2) 555 errx(1, "vringh_iov_push_user: %i", err); 556 assert(memcmp(__user_addr_max - 3, "bc", 2) == 0); 557 assert(wiov.i == wiov.used); 558 assert(vringh_iov_push_user(&wiov, buf, 5) == 0); 559 560 /* Host is done. */ 561 err = vringh_complete_user(&vrh, head, err); 562 if (err != 0) 563 errx(1, "vringh_complete_user: %i", err); 564 565 /* Guest should see used token now. */ 566 __kfree_ignore_start = __user_addr_min + vring_size(RINGSIZE, ALIGN); 567 __kfree_ignore_end = __kfree_ignore_start + 1; 568 ret = virtqueue_get_buf(vq, &i); 569 if (ret != &err) 570 errx(1, "virtqueue_get_buf: %p", ret); 571 assert(i == 2); 572 573 /* Guest puts in a huge descriptor. */ 574 sg_init_table(guest_sg, RINGSIZE); 575 for (i = 0; i < RINGSIZE; i++) { 576 sg_set_buf(&guest_sg[i], 577 __user_addr_max - USER_MEM/4, USER_MEM/4); 578 } 579 580 /* Fill contents with recognisable garbage. */ 581 for (i = 0; i < USER_MEM/4; i++) 582 ((char *)__user_addr_max - USER_MEM/4)[i] = i; 583 584 /* This will allocate an indirect, so force it to allocate user addr */ 585 __kmalloc_fake = __user_addr_min + vring_size(RINGSIZE, ALIGN); 586 err = virtqueue_add_outbuf(vq, guest_sg, RINGSIZE, &err, GFP_KERNEL); 587 if (err) 588 errx(1, "virtqueue_add_outbuf (large): %i", err); 589 __kmalloc_fake = NULL; 590 591 /* Host picks it up (allocates new iov). */ 592 vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov)); 593 vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov)); 594 595 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head); 596 if (err != 1) 597 errx(1, "vringh_getdesc_user: %i", err); 598 599 assert(riov.max_num & VRINGH_IOV_ALLOCATED); 600 assert(riov.iov != host_riov); 601 if (getrange != getrange_slow) 602 assert(riov.used == RINGSIZE); 603 else 604 assert(riov.used == RINGSIZE * USER_MEM/4); 605 606 assert(!(wiov.max_num & VRINGH_IOV_ALLOCATED)); 607 assert(wiov.used == 0); 608 609 /* Pull data back out (in odd chunks), should be as expected. */ 610 for (i = 0; i < RINGSIZE * USER_MEM/4; i += 3) { 611 err = vringh_iov_pull_user(&riov, buf, 3); 612 if (err != 3 && i + err != RINGSIZE * USER_MEM/4) 613 errx(1, "vringh_iov_pull_user large: %i", err); 614 assert(buf[0] == (char)i); 615 assert(err < 2 || buf[1] == (char)(i + 1)); 616 assert(err < 3 || buf[2] == (char)(i + 2)); 617 } 618 assert(riov.i == riov.used); 619 vringh_iov_cleanup(&riov); 620 vringh_iov_cleanup(&wiov); 621 622 /* Complete using multi interface, just because we can. */ 623 used[0].id = head; 624 used[0].len = 0; 625 err = vringh_complete_multi_user(&vrh, used, 1); 626 if (err) 627 errx(1, "vringh_complete_multi_user(1): %i", err); 628 629 /* Free up those descriptors. */ 630 ret = virtqueue_get_buf(vq, &i); 631 if (ret != &err) 632 errx(1, "virtqueue_get_buf: %p", ret); 633 634 /* Add lots of descriptors. */ 635 sg_init_table(guest_sg, 1); 636 sg_set_buf(&guest_sg[0], __user_addr_max - 1, 1); 637 for (i = 0; i < RINGSIZE; i++) { 638 err = virtqueue_add_outbuf(vq, guest_sg, 1, &err, GFP_KERNEL); 639 if (err) 640 errx(1, "virtqueue_add_outbuf (multiple): %i", err); 641 } 642 643 /* Now get many, and consume them all at once. */ 644 vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov)); 645 vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov)); 646 647 for (i = 0; i < RINGSIZE; i++) { 648 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head); 649 if (err != 1) 650 errx(1, "vringh_getdesc_user: %i", err); 651 used[i].id = head; 652 used[i].len = 0; 653 } 654 /* Make sure it wraps around ring, to test! */ 655 assert(vrh.vring.used->idx % RINGSIZE != 0); 656 err = vringh_complete_multi_user(&vrh, used, RINGSIZE); 657 if (err) 658 errx(1, "vringh_complete_multi_user: %i", err); 659 660 /* Free those buffers. */ 661 for (i = 0; i < RINGSIZE; i++) { 662 unsigned len; 663 assert(virtqueue_get_buf(vq, &len) != NULL); 664 } 665 666 /* Test weird (but legal!) indirect. */ 667 if (__virtio_test_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC)) { 668 char *data = __user_addr_max - USER_MEM/4; 669 struct vring_desc *d = __user_addr_max - USER_MEM/2; 670 struct vring vring; 671 672 /* Force creation of direct, which we modify. */ 673 __virtio_clear_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC); 674 vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &vdev, true, 675 false, __user_addr_min, 676 never_notify_host, 677 never_callback_guest, 678 "guest vq"); 679 680 sg_init_table(guest_sg, 4); 681 sg_set_buf(&guest_sg[0], d, sizeof(*d)*2); 682 sg_set_buf(&guest_sg[1], d + 2, sizeof(*d)*1); 683 sg_set_buf(&guest_sg[2], data + 6, 4); 684 sg_set_buf(&guest_sg[3], d + 3, sizeof(*d)*3); 685 686 err = virtqueue_add_outbuf(vq, guest_sg, 4, &err, GFP_KERNEL); 687 if (err) 688 errx(1, "virtqueue_add_outbuf (indirect): %i", err); 689 690 vring_init(&vring, RINGSIZE, __user_addr_min, ALIGN); 691 692 /* They're used in order, but double-check... */ 693 assert(vring.desc[0].addr == (unsigned long)d); 694 assert(vring.desc[1].addr == (unsigned long)(d+2)); 695 assert(vring.desc[2].addr == (unsigned long)data + 6); 696 assert(vring.desc[3].addr == (unsigned long)(d+3)); 697 vring.desc[0].flags |= VRING_DESC_F_INDIRECT; 698 vring.desc[1].flags |= VRING_DESC_F_INDIRECT; 699 vring.desc[3].flags |= VRING_DESC_F_INDIRECT; 700 701 /* First indirect */ 702 d[0].addr = (unsigned long)data; 703 d[0].len = 1; 704 d[0].flags = VRING_DESC_F_NEXT; 705 d[0].next = 1; 706 d[1].addr = (unsigned long)data + 1; 707 d[1].len = 2; 708 d[1].flags = 0; 709 710 /* Second indirect */ 711 d[2].addr = (unsigned long)data + 3; 712 d[2].len = 3; 713 d[2].flags = 0; 714 715 /* Third indirect */ 716 d[3].addr = (unsigned long)data + 10; 717 d[3].len = 5; 718 d[3].flags = VRING_DESC_F_NEXT; 719 d[3].next = 1; 720 d[4].addr = (unsigned long)data + 15; 721 d[4].len = 6; 722 d[4].flags = VRING_DESC_F_NEXT; 723 d[4].next = 2; 724 d[5].addr = (unsigned long)data + 21; 725 d[5].len = 7; 726 d[5].flags = 0; 727 728 /* Host picks it up (allocates new iov). */ 729 vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov)); 730 vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov)); 731 732 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head); 733 if (err != 1) 734 errx(1, "vringh_getdesc_user: %i", err); 735 736 if (head != 0) 737 errx(1, "vringh_getdesc_user: head %i not 0", head); 738 739 assert(riov.max_num & VRINGH_IOV_ALLOCATED); 740 if (getrange != getrange_slow) 741 assert(riov.used == 7); 742 else 743 assert(riov.used == 28); 744 err = vringh_iov_pull_user(&riov, buf, 29); 745 assert(err == 28); 746 747 /* Data should be linear. */ 748 for (i = 0; i < err; i++) 749 assert(buf[i] == i); 750 vringh_iov_cleanup(&riov); 751 } 752 753 /* Don't leak memory... */ 754 vring_del_virtqueue(vq); 755 free(__user_addr_min); 756 757 return 0; 758 } 759