1 // SPDX-License-Identifier: GPL-2.0
2 /* Simple test of virtio code, entirely in userspace. */
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
never_notify_host(struct virtqueue * vq)27 static bool never_notify_host(struct virtqueue *vq)
28 {
29 abort();
30 }
31
never_callback_guest(struct virtqueue * vq)32 static void never_callback_guest(struct virtqueue *vq)
33 {
34 abort();
35 }
36
getrange_iov(struct vringh * vrh,u64 addr,struct vringh_range * r)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. */
getrange_slow(struct vringh * vrh,u64 addr,struct vringh_range * r)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
parallel_notify_host(struct virtqueue * vq)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
no_notify_host(struct virtqueue * vq)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. */
find_cpus(unsigned int * first,unsigned int * last)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 */
vringh_get_head(struct vringh * vrh,u16 * head)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
parallel_test(u64 features,bool (* getrange)(struct vringh * vrh,u64 addr,struct vringh_range * r),bool fast_vringh)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 if (host_map == MAP_FAILED)
163 err(1, "mmap host_map");
164
165 guest_map = mmap(NULL, mapsize, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
166 if (guest_map == MAP_FAILED)
167 err(1, "mmap guest_map");
168
169 pipe_ret = pipe(to_guest);
170 assert(!pipe_ret);
171
172 pipe_ret = pipe(to_host);
173 assert(!pipe_ret);
174
175 CPU_ZERO(&cpu_set);
176 find_cpus(&first_cpu, &last_cpu);
177 printf("Using CPUS %u and %u\n", first_cpu, last_cpu);
178 fflush(stdout);
179
180 if (fork() != 0) {
181 struct vringh vrh;
182 int status, err, rlen = 0;
183 char rbuf[5];
184
185 /* We are the host: never access guest addresses! */
186 munmap(guest_map, mapsize);
187
188 __user_addr_min = host_map;
189 __user_addr_max = __user_addr_min + mapsize;
190 user_addr_offset = host_map - guest_map;
191 assert(user_addr_offset);
192
193 close(to_guest[0]);
194 close(to_host[1]);
195
196 vring_init(&vrh.vring, RINGSIZE, host_map, ALIGN);
197 vringh_init_user(&vrh, features, RINGSIZE, true,
198 vrh.vring.desc, vrh.vring.avail, vrh.vring.used);
199 CPU_SET(first_cpu, &cpu_set);
200 if (sched_setaffinity(getpid(), sizeof(cpu_set), &cpu_set))
201 errx(1, "Could not set affinity to cpu %u", first_cpu);
202
203 while (xfers < NUM_XFERS) {
204 struct iovec host_riov[2], host_wiov[2];
205 struct vringh_iov riov, wiov;
206 u16 head, written;
207
208 if (fast_vringh) {
209 for (;;) {
210 err = vringh_get_head(&vrh, &head);
211 if (err != 0)
212 break;
213 err = vringh_need_notify_user(&vrh);
214 if (err < 0)
215 errx(1, "vringh_need_notify_user: %i",
216 err);
217 if (err) {
218 write(to_guest[1], "", 1);
219 notifies++;
220 }
221 }
222 if (err != 1)
223 errx(1, "vringh_get_head");
224 written = 0;
225 goto complete;
226 } else {
227 vringh_iov_init(&riov,
228 host_riov,
229 ARRAY_SIZE(host_riov));
230 vringh_iov_init(&wiov,
231 host_wiov,
232 ARRAY_SIZE(host_wiov));
233
234 err = vringh_getdesc_user(&vrh, &riov, &wiov,
235 getrange, &head);
236 }
237 if (err == 0) {
238 err = vringh_need_notify_user(&vrh);
239 if (err < 0)
240 errx(1, "vringh_need_notify_user: %i",
241 err);
242 if (err) {
243 write(to_guest[1], "", 1);
244 notifies++;
245 }
246
247 if (!vringh_notify_enable_user(&vrh))
248 continue;
249
250 /* Swallow all notifies at once. */
251 if (read(to_host[0], buf, sizeof(buf)) < 1)
252 break;
253
254 vringh_notify_disable_user(&vrh);
255 receives++;
256 continue;
257 }
258 if (err != 1)
259 errx(1, "vringh_getdesc_user: %i", err);
260
261 /* We simply copy bytes. */
262 if (riov.used) {
263 rlen = vringh_iov_pull_user(&riov, rbuf,
264 sizeof(rbuf));
265 if (rlen != 4)
266 errx(1, "vringh_iov_pull_user: %i",
267 rlen);
268 assert(riov.i == riov.used);
269 written = 0;
270 } else {
271 err = vringh_iov_push_user(&wiov, rbuf, rlen);
272 if (err != rlen)
273 errx(1, "vringh_iov_push_user: %i",
274 err);
275 assert(wiov.i == wiov.used);
276 written = err;
277 }
278 complete:
279 xfers++;
280
281 err = vringh_complete_user(&vrh, head, written);
282 if (err != 0)
283 errx(1, "vringh_complete_user: %i", err);
284 }
285
286 err = vringh_need_notify_user(&vrh);
287 if (err < 0)
288 errx(1, "vringh_need_notify_user: %i", err);
289 if (err) {
290 write(to_guest[1], "", 1);
291 notifies++;
292 }
293 wait(&status);
294 if (!WIFEXITED(status))
295 errx(1, "Child died with signal %i?", WTERMSIG(status));
296 if (WEXITSTATUS(status) != 0)
297 errx(1, "Child exited %i?", WEXITSTATUS(status));
298 printf("Host: notified %lu, pinged %lu\n", notifies, receives);
299 return 0;
300 } else {
301 struct guest_virtio_device gvdev;
302 struct virtqueue *vq;
303 unsigned int *data;
304 struct vring_desc *indirects;
305 unsigned int finished = 0;
306
307 /* We pass sg[]s pointing into here, but we need RINGSIZE+1 */
308 data = guest_map + vring_size(RINGSIZE, ALIGN);
309 indirects = (void *)data + (RINGSIZE + 1) * 2 * sizeof(int);
310
311 /* We are the guest. */
312 munmap(host_map, mapsize);
313
314 close(to_guest[1]);
315 close(to_host[0]);
316
317 gvdev.vdev.features = features;
318 INIT_LIST_HEAD(&gvdev.vdev.vqs);
319 spin_lock_init(&gvdev.vdev.vqs_list_lock);
320 gvdev.to_host_fd = to_host[1];
321 gvdev.notifies = 0;
322
323 CPU_SET(first_cpu, &cpu_set);
324 if (sched_setaffinity(getpid(), sizeof(cpu_set), &cpu_set))
325 err(1, "Could not set affinity to cpu %u", first_cpu);
326
327 vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &gvdev.vdev, true,
328 false, guest_map,
329 fast_vringh ? no_notify_host
330 : parallel_notify_host,
331 never_callback_guest, "guest vq");
332
333 /* Don't kfree indirects. */
334 __kfree_ignore_start = indirects;
335 __kfree_ignore_end = indirects + RINGSIZE * 6;
336
337 while (xfers < NUM_XFERS) {
338 struct scatterlist sg[4];
339 unsigned int num_sg, len;
340 int *dbuf, err;
341 bool output = !(xfers % 2);
342
343 /* Consume bufs. */
344 while ((dbuf = virtqueue_get_buf(vq, &len)) != NULL) {
345 if (len == 4)
346 assert(*dbuf == finished - 1);
347 else if (!fast_vringh)
348 assert(*dbuf == finished);
349 finished++;
350 }
351
352 /* Produce a buffer. */
353 dbuf = data + (xfers % (RINGSIZE + 1));
354
355 if (output)
356 *dbuf = xfers;
357 else
358 *dbuf = -1;
359
360 switch ((xfers / sizeof(*dbuf)) % 4) {
361 case 0:
362 /* Nasty three-element sg list. */
363 sg_init_table(sg, num_sg = 3);
364 sg_set_buf(&sg[0], (void *)dbuf, 1);
365 sg_set_buf(&sg[1], (void *)dbuf + 1, 2);
366 sg_set_buf(&sg[2], (void *)dbuf + 3, 1);
367 break;
368 case 1:
369 sg_init_table(sg, num_sg = 2);
370 sg_set_buf(&sg[0], (void *)dbuf, 1);
371 sg_set_buf(&sg[1], (void *)dbuf + 1, 3);
372 break;
373 case 2:
374 sg_init_table(sg, num_sg = 1);
375 sg_set_buf(&sg[0], (void *)dbuf, 4);
376 break;
377 case 3:
378 sg_init_table(sg, num_sg = 4);
379 sg_set_buf(&sg[0], (void *)dbuf, 1);
380 sg_set_buf(&sg[1], (void *)dbuf + 1, 1);
381 sg_set_buf(&sg[2], (void *)dbuf + 2, 1);
382 sg_set_buf(&sg[3], (void *)dbuf + 3, 1);
383 break;
384 }
385
386 /* May allocate an indirect, so force it to allocate
387 * user addr */
388 __kmalloc_fake = indirects + (xfers % RINGSIZE) * 4;
389 if (output)
390 err = virtqueue_add_outbuf(vq, sg, num_sg, dbuf,
391 GFP_KERNEL);
392 else
393 err = virtqueue_add_inbuf(vq, sg, num_sg,
394 dbuf, GFP_KERNEL);
395
396 if (err == -ENOSPC) {
397 if (!virtqueue_enable_cb_delayed(vq))
398 continue;
399 /* Swallow all notifies at once. */
400 if (read(to_guest[0], buf, sizeof(buf)) < 1)
401 break;
402
403 receives++;
404 virtqueue_disable_cb(vq);
405 continue;
406 }
407
408 if (err)
409 errx(1, "virtqueue_add_in/outbuf: %i", err);
410
411 xfers++;
412 virtqueue_kick(vq);
413 }
414
415 /* Any extra? */
416 while (finished != xfers) {
417 int *dbuf;
418 unsigned int len;
419
420 /* Consume bufs. */
421 dbuf = virtqueue_get_buf(vq, &len);
422 if (dbuf) {
423 if (len == 4)
424 assert(*dbuf == finished - 1);
425 else
426 assert(len == 0);
427 finished++;
428 continue;
429 }
430
431 if (!virtqueue_enable_cb_delayed(vq))
432 continue;
433 if (read(to_guest[0], buf, sizeof(buf)) < 1)
434 break;
435
436 receives++;
437 virtqueue_disable_cb(vq);
438 }
439
440 printf("Guest: notified %lu, pinged %lu\n",
441 gvdev.notifies, receives);
442 vring_del_virtqueue(vq);
443 return 0;
444 }
445 }
446
main(int argc,char * argv[])447 int main(int argc, char *argv[])
448 {
449 struct virtio_device vdev;
450 struct virtqueue *vq;
451 struct vringh vrh;
452 struct scatterlist guest_sg[RINGSIZE], *sgs[2];
453 struct iovec host_riov[2], host_wiov[2];
454 struct vringh_iov riov, wiov;
455 struct vring_used_elem used[RINGSIZE];
456 char buf[28];
457 u16 head;
458 int err;
459 unsigned i;
460 void *ret;
461 bool (*getrange)(struct vringh *vrh, u64 addr, struct vringh_range *r);
462 bool fast_vringh = false, parallel = false;
463
464 getrange = getrange_iov;
465 vdev.features = 0;
466 INIT_LIST_HEAD(&vdev.vqs);
467 spin_lock_init(&vdev.vqs_list_lock);
468
469 while (argv[1]) {
470 if (strcmp(argv[1], "--indirect") == 0)
471 __virtio_set_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC);
472 else if (strcmp(argv[1], "--eventidx") == 0)
473 __virtio_set_bit(&vdev, VIRTIO_RING_F_EVENT_IDX);
474 else if (strcmp(argv[1], "--virtio-1") == 0)
475 __virtio_set_bit(&vdev, VIRTIO_F_VERSION_1);
476 else if (strcmp(argv[1], "--slow-range") == 0)
477 getrange = getrange_slow;
478 else if (strcmp(argv[1], "--fast-vringh") == 0)
479 fast_vringh = true;
480 else if (strcmp(argv[1], "--parallel") == 0)
481 parallel = true;
482 else
483 errx(1, "Unknown arg %s", argv[1]);
484 argv++;
485 }
486
487 if (parallel)
488 return parallel_test(vdev.features, getrange, fast_vringh);
489
490 if (posix_memalign(&__user_addr_min, PAGE_SIZE, USER_MEM) != 0)
491 abort();
492 __user_addr_max = __user_addr_min + USER_MEM;
493 memset(__user_addr_min, 0, vring_size(RINGSIZE, ALIGN));
494
495 /* Set up guest side. */
496 vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &vdev, true, false,
497 __user_addr_min,
498 never_notify_host, never_callback_guest,
499 "guest vq");
500
501 /* Set up host side. */
502 vring_init(&vrh.vring, RINGSIZE, __user_addr_min, ALIGN);
503 vringh_init_user(&vrh, vdev.features, RINGSIZE, true,
504 vrh.vring.desc, vrh.vring.avail, vrh.vring.used);
505
506 /* No descriptor to get yet... */
507 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);
508 if (err != 0)
509 errx(1, "vringh_getdesc_user: %i", err);
510
511 /* Guest puts in a descriptor. */
512 memcpy(__user_addr_max - 1, "a", 1);
513 sg_init_table(guest_sg, 1);
514 sg_set_buf(&guest_sg[0], __user_addr_max - 1, 1);
515 sg_init_table(guest_sg+1, 1);
516 sg_set_buf(&guest_sg[1], __user_addr_max - 3, 2);
517 sgs[0] = &guest_sg[0];
518 sgs[1] = &guest_sg[1];
519
520 /* May allocate an indirect, so force it to allocate user addr */
521 __kmalloc_fake = __user_addr_min + vring_size(RINGSIZE, ALIGN);
522 err = virtqueue_add_sgs(vq, sgs, 1, 1, &err, GFP_KERNEL);
523 if (err)
524 errx(1, "virtqueue_add_sgs: %i", err);
525 __kmalloc_fake = NULL;
526
527 /* Host retrieves it. */
528 vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov));
529 vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov));
530
531 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);
532 if (err != 1)
533 errx(1, "vringh_getdesc_user: %i", err);
534
535 assert(riov.used == 1);
536 assert(riov.iov[0].iov_base == __user_addr_max - 1);
537 assert(riov.iov[0].iov_len == 1);
538 if (getrange != getrange_slow) {
539 assert(wiov.used == 1);
540 assert(wiov.iov[0].iov_base == __user_addr_max - 3);
541 assert(wiov.iov[0].iov_len == 2);
542 } else {
543 assert(wiov.used == 2);
544 assert(wiov.iov[0].iov_base == __user_addr_max - 3);
545 assert(wiov.iov[0].iov_len == 1);
546 assert(wiov.iov[1].iov_base == __user_addr_max - 2);
547 assert(wiov.iov[1].iov_len == 1);
548 }
549
550 err = vringh_iov_pull_user(&riov, buf, 5);
551 if (err != 1)
552 errx(1, "vringh_iov_pull_user: %i", err);
553 assert(buf[0] == 'a');
554 assert(riov.i == 1);
555 assert(vringh_iov_pull_user(&riov, buf, 5) == 0);
556
557 memcpy(buf, "bcdef", 5);
558 err = vringh_iov_push_user(&wiov, buf, 5);
559 if (err != 2)
560 errx(1, "vringh_iov_push_user: %i", err);
561 assert(memcmp(__user_addr_max - 3, "bc", 2) == 0);
562 assert(wiov.i == wiov.used);
563 assert(vringh_iov_push_user(&wiov, buf, 5) == 0);
564
565 /* Host is done. */
566 err = vringh_complete_user(&vrh, head, err);
567 if (err != 0)
568 errx(1, "vringh_complete_user: %i", err);
569
570 /* Guest should see used token now. */
571 __kfree_ignore_start = __user_addr_min + vring_size(RINGSIZE, ALIGN);
572 __kfree_ignore_end = __kfree_ignore_start + 1;
573 ret = virtqueue_get_buf(vq, &i);
574 if (ret != &err)
575 errx(1, "virtqueue_get_buf: %p", ret);
576 assert(i == 2);
577
578 /* Guest puts in a huge descriptor. */
579 sg_init_table(guest_sg, RINGSIZE);
580 for (i = 0; i < RINGSIZE; i++) {
581 sg_set_buf(&guest_sg[i],
582 __user_addr_max - USER_MEM/4, USER_MEM/4);
583 }
584
585 /* Fill contents with recognisable garbage. */
586 for (i = 0; i < USER_MEM/4; i++)
587 ((char *)__user_addr_max - USER_MEM/4)[i] = i;
588
589 /* This will allocate an indirect, so force it to allocate user addr */
590 __kmalloc_fake = __user_addr_min + vring_size(RINGSIZE, ALIGN);
591 err = virtqueue_add_outbuf(vq, guest_sg, RINGSIZE, &err, GFP_KERNEL);
592 if (err)
593 errx(1, "virtqueue_add_outbuf (large): %i", err);
594 __kmalloc_fake = NULL;
595
596 /* Host picks it up (allocates new iov). */
597 vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov));
598 vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov));
599
600 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);
601 if (err != 1)
602 errx(1, "vringh_getdesc_user: %i", err);
603
604 assert(riov.max_num & VRINGH_IOV_ALLOCATED);
605 assert(riov.iov != host_riov);
606 if (getrange != getrange_slow)
607 assert(riov.used == RINGSIZE);
608 else
609 assert(riov.used == RINGSIZE * USER_MEM/4);
610
611 assert(!(wiov.max_num & VRINGH_IOV_ALLOCATED));
612 assert(wiov.used == 0);
613
614 /* Pull data back out (in odd chunks), should be as expected. */
615 for (i = 0; i < RINGSIZE * USER_MEM/4; i += 3) {
616 err = vringh_iov_pull_user(&riov, buf, 3);
617 if (err != 3 && i + err != RINGSIZE * USER_MEM/4)
618 errx(1, "vringh_iov_pull_user large: %i", err);
619 assert(buf[0] == (char)i);
620 assert(err < 2 || buf[1] == (char)(i + 1));
621 assert(err < 3 || buf[2] == (char)(i + 2));
622 }
623 assert(riov.i == riov.used);
624 vringh_iov_cleanup(&riov);
625 vringh_iov_cleanup(&wiov);
626
627 /* Complete using multi interface, just because we can. */
628 used[0].id = head;
629 used[0].len = 0;
630 err = vringh_complete_multi_user(&vrh, used, 1);
631 if (err)
632 errx(1, "vringh_complete_multi_user(1): %i", err);
633
634 /* Free up those descriptors. */
635 ret = virtqueue_get_buf(vq, &i);
636 if (ret != &err)
637 errx(1, "virtqueue_get_buf: %p", ret);
638
639 /* Add lots of descriptors. */
640 sg_init_table(guest_sg, 1);
641 sg_set_buf(&guest_sg[0], __user_addr_max - 1, 1);
642 for (i = 0; i < RINGSIZE; i++) {
643 err = virtqueue_add_outbuf(vq, guest_sg, 1, &err, GFP_KERNEL);
644 if (err)
645 errx(1, "virtqueue_add_outbuf (multiple): %i", err);
646 }
647
648 /* Now get many, and consume them all at once. */
649 vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov));
650 vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov));
651
652 for (i = 0; i < RINGSIZE; i++) {
653 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);
654 if (err != 1)
655 errx(1, "vringh_getdesc_user: %i", err);
656 used[i].id = head;
657 used[i].len = 0;
658 }
659 /* Make sure it wraps around ring, to test! */
660 assert(vrh.vring.used->idx % RINGSIZE != 0);
661 err = vringh_complete_multi_user(&vrh, used, RINGSIZE);
662 if (err)
663 errx(1, "vringh_complete_multi_user: %i", err);
664
665 /* Free those buffers. */
666 for (i = 0; i < RINGSIZE; i++) {
667 unsigned len;
668 assert(virtqueue_get_buf(vq, &len) != NULL);
669 }
670
671 /* Test weird (but legal!) indirect. */
672 if (__virtio_test_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC)) {
673 char *data = __user_addr_max - USER_MEM/4;
674 struct vring_desc *d = __user_addr_max - USER_MEM/2;
675 struct vring vring;
676
677 /* Force creation of direct, which we modify. */
678 __virtio_clear_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC);
679 vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &vdev, true,
680 false, __user_addr_min,
681 never_notify_host,
682 never_callback_guest,
683 "guest vq");
684
685 sg_init_table(guest_sg, 4);
686 sg_set_buf(&guest_sg[0], d, sizeof(*d)*2);
687 sg_set_buf(&guest_sg[1], d + 2, sizeof(*d)*1);
688 sg_set_buf(&guest_sg[2], data + 6, 4);
689 sg_set_buf(&guest_sg[3], d + 3, sizeof(*d)*3);
690
691 err = virtqueue_add_outbuf(vq, guest_sg, 4, &err, GFP_KERNEL);
692 if (err)
693 errx(1, "virtqueue_add_outbuf (indirect): %i", err);
694
695 vring_init(&vring, RINGSIZE, __user_addr_min, ALIGN);
696
697 /* They're used in order, but double-check... */
698 assert(vring.desc[0].addr == (unsigned long)d);
699 assert(vring.desc[1].addr == (unsigned long)(d+2));
700 assert(vring.desc[2].addr == (unsigned long)data + 6);
701 assert(vring.desc[3].addr == (unsigned long)(d+3));
702 vring.desc[0].flags |= VRING_DESC_F_INDIRECT;
703 vring.desc[1].flags |= VRING_DESC_F_INDIRECT;
704 vring.desc[3].flags |= VRING_DESC_F_INDIRECT;
705
706 /* First indirect */
707 d[0].addr = (unsigned long)data;
708 d[0].len = 1;
709 d[0].flags = VRING_DESC_F_NEXT;
710 d[0].next = 1;
711 d[1].addr = (unsigned long)data + 1;
712 d[1].len = 2;
713 d[1].flags = 0;
714
715 /* Second indirect */
716 d[2].addr = (unsigned long)data + 3;
717 d[2].len = 3;
718 d[2].flags = 0;
719
720 /* Third indirect */
721 d[3].addr = (unsigned long)data + 10;
722 d[3].len = 5;
723 d[3].flags = VRING_DESC_F_NEXT;
724 d[3].next = 1;
725 d[4].addr = (unsigned long)data + 15;
726 d[4].len = 6;
727 d[4].flags = VRING_DESC_F_NEXT;
728 d[4].next = 2;
729 d[5].addr = (unsigned long)data + 21;
730 d[5].len = 7;
731 d[5].flags = 0;
732
733 /* Host picks it up (allocates new iov). */
734 vringh_iov_init(&riov, host_riov, ARRAY_SIZE(host_riov));
735 vringh_iov_init(&wiov, host_wiov, ARRAY_SIZE(host_wiov));
736
737 err = vringh_getdesc_user(&vrh, &riov, &wiov, getrange, &head);
738 if (err != 1)
739 errx(1, "vringh_getdesc_user: %i", err);
740
741 if (head != 0)
742 errx(1, "vringh_getdesc_user: head %i not 0", head);
743
744 assert(riov.max_num & VRINGH_IOV_ALLOCATED);
745 if (getrange != getrange_slow)
746 assert(riov.used == 7);
747 else
748 assert(riov.used == 28);
749 err = vringh_iov_pull_user(&riov, buf, 29);
750 assert(err == 28);
751
752 /* Data should be linear. */
753 for (i = 0; i < err; i++)
754 assert(buf[i] == i);
755 vringh_iov_cleanup(&riov);
756 }
757
758 /* Don't leak memory... */
759 vring_del_virtqueue(vq);
760 free(__user_addr_min);
761
762 return 0;
763 }
764