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Merge tag 'mm-nonmm-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-block.git] / tools / virtio / vringh_test.c
CommitLineData
b2441318 1// SPDX-License-Identifier: GPL-2.0
1515c5ce
RR		 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>
2eaa614b 11#include <linux/virtio_config.h>
1515c5ce
RR		 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)
20void *__user_addr_min, *__user_addr_max;
21void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end;
22static u64 user_addr_offset;
23
24#define RINGSIZE 256
25#define ALIGN 4096
26
46f9c2b9 27static bool never_notify_host(struct virtqueue *vq)
1515c5ce
RR		 28{
29 abort();
30}
31
32static void never_callback_guest(struct virtqueue *vq)
33{
34 abort();
35}
36
37static 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. */
51static 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
64struct guest_virtio_device {
65 struct virtio_device vdev;
66 int to_host_fd;
67 unsigned long notifies;
68};
69
46f9c2b9 70static bool parallel_notify_host(struct virtqueue *vq)
1515c5ce 71{
46f9c2b9 72 int rc;
1515c5ce
RR		 73 struct guest_virtio_device *gvdev;
74
75 gvdev = container_of(vq->vdev, struct guest_virtio_device, vdev);
46f9c2b9
HG		 76 rc = write(gvdev->to_host_fd, "", 1);
77 if (rc < 0)
78 return false;
1515c5ce 79 gvdev->notifies++;
46f9c2b9 80 return true;
1515c5ce
RR		 81}
82
46f9c2b9 83static bool no_notify_host(struct virtqueue *vq)
1515c5ce 84{
46f9c2b9 85 return true;
1515c5ce
RR		 86}
87
88#define NUM_XFERS (10000000)
89
90/* We aim for two "distant" cpus. */
91static 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 */
111static 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
e3edf032 136static int parallel_test(u64 features,
1515c5ce
RR		 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
e16e12be 309 gvdev.vdev.features = features;
cb91909e 310 INIT_LIST_HEAD(&gvdev.vdev.vqs);
1515c5ce
RR		 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,
0a12ae40
SN		 319 false, guest_map,
320 fast_vringh ? no_notify_host
1515c5ce
RR		 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)
e538ebaf
RR		 381 err = virtqueue_add_outbuf(vq, sg, num_sg, dbuf,
382 GFP_KERNEL);
1515c5ce 383 else
e538ebaf
RR		 384 err = virtqueue_add_inbuf(vq, sg, num_sg,
385 dbuf, GFP_KERNEL);
1515c5ce
RR		 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)
cf994e0a 400 errx(1, "virtqueue_add_in/outbuf: %i", err);
1515c5ce
RR		 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
438int main(int argc, char *argv[])
439{
440 struct virtio_device vdev;
441 struct virtqueue *vq;
442 struct vringh vrh;
cf994e0a 443 struct scatterlist guest_sg[RINGSIZE], *sgs[2];
1515c5ce
RR		 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;
e16e12be 456 vdev.features = 0;
cb91909e 457 INIT_LIST_HEAD(&vdev.vqs);
1515c5ce
RR		 458
459 while (argv[1]) {
460 if (strcmp(argv[1], "--indirect") == 0)
e16e12be 461 __virtio_set_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC);
1515c5ce 462 else if (strcmp(argv[1], "--eventidx") == 0)
e16e12be 463 __virtio_set_bit(&vdev, VIRTIO_RING_F_EVENT_IDX);
8dc32b29
MT		 464 else if (strcmp(argv[1], "--virtio-1") == 0)
465 __virtio_set_bit(&vdev, VIRTIO_F_VERSION_1);
1515c5ce
RR		 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)
e16e12be 478 return parallel_test(vdev.features, getrange, fast_vringh);
1515c5ce
RR		 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. */
0a12ae40 486 vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &vdev, true, false,
1515c5ce
RR		 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);
e16e12be 493 vringh_init_user(&vrh, vdev.features, RINGSIZE, true,
1515c5ce
RR		 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);
cf994e0a
RR		 507 sgs[0] = &guest_sg[0];
508 sgs[1] = &guest_sg[1];
1515c5ce
RR		 509
510 /* May allocate an indirect, so force it to allocate user addr */
511 __kmalloc_fake = __user_addr_min + vring_size(RINGSIZE, ALIGN);
cf994e0a 512 err = virtqueue_add_sgs(vq, sgs, 1, 1, &err, GFP_KERNEL);
1515c5ce 513 if (err)
cf994e0a 514 errx(1, "virtqueue_add_sgs: %i", err);
1515c5ce
RR		 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);
cf994e0a 581 err = virtqueue_add_outbuf(vq, guest_sg, RINGSIZE, &err, GFP_KERNEL);
1515c5ce 582 if (err)
cf994e0a 583 errx(1, "virtqueue_add_outbuf (large): %i", err);
1515c5ce
RR		 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++) {
cf994e0a 633 err = virtqueue_add_outbuf(vq, guest_sg, 1, &err, GFP_KERNEL);
1515c5ce 634 if (err)
cf994e0a 635 errx(1, "virtqueue_add_outbuf (multiple): %i", err);
1515c5ce
RR		 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. */
e16e12be 662 if (__virtio_test_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC)) {
1515c5ce
RR		 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. */
e16e12be 668 __virtio_clear_bit(&vdev, VIRTIO_RING_F_INDIRECT_DESC);
1515c5ce 669 vq = vring_new_virtqueue(0, RINGSIZE, ALIGN, &vdev, true,
0a12ae40 670 false, __user_addr_min,
1515c5ce
RR		 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
cf994e0a 681 err = virtqueue_add_outbuf(vq, guest_sg, 4, &err, GFP_KERNEL);
1515c5ce 682 if (err)
cf994e0a 683 errx(1, "virtqueue_add_outbuf (indirect): %i", err);
1515c5ce
RR		 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}
Linux 6.x block layer and io_uring tree(s)