?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
iotest 302: use img_info_log() helper
[qemu.git] / subprojects / libvhost-user / libvhost-user.c
blob787f4d2d4fef8311d994399e55dd36223f881f9b
1 /*
2 * Vhost User library
3 *
4 * Copyright IBM, Corp. 2007
5 * Copyright (c) 2016 Red Hat, Inc.
6 *
7 * Authors:
8 * Anthony Liguori <aliguori@us.ibm.com>
9 * Marc-André Lureau <mlureau@redhat.com>
10 * Victor Kaplansky <victork@redhat.com>
11 *
12 * This work is licensed under the terms of the GNU GPL, version 2 or
13 * later. See the COPYING file in the top-level directory.
14 */
15
16 /* this code avoids GLib dependency */
17 #include <stdlib.h>
18 #include <stdio.h>
19 #include <unistd.h>
20 #include <stdarg.h>
21 #include <errno.h>
22 #include <string.h>
23 #include <assert.h>
24 #include <inttypes.h>
25 #include <sys/types.h>
26 #include <sys/socket.h>
27 #include <sys/eventfd.h>
28 #include <sys/mman.h>
29 #include <endian.h>
30
31 #if defined(__linux__)
32 #include <sys/syscall.h>
33 #include <fcntl.h>
34 #include <sys/ioctl.h>
35 #include <linux/vhost.h>
36
37 #ifdef __NR_userfaultfd
38 #include <linux/userfaultfd.h>
39 #endif
40
41 #endif
42
43 #include "include/atomic.h"
44
45 #include "libvhost-user.h"
46
47 /* usually provided by GLib */
48 #ifndef MIN
49 #define MIN(x, y) ({ \
50 typeof(x) _min1 = (x); \
51 typeof(y) _min2 = (y); \
52 (void) (&_min1 == &_min2); \
53 _min1 < _min2 ? _min1 : _min2; })
54 #endif
55
56 /* Round number down to multiple */
57 #define ALIGN_DOWN(n, m) ((n) / (m) * (m))
58
59 /* Round number up to multiple */
60 #define ALIGN_UP(n, m) ALIGN_DOWN((n) + (m) - 1, (m))
61
62 #ifndef unlikely
63 #define unlikely(x) __builtin_expect(!!(x), 0)
64 #endif
65
66 /* Align each region to cache line size in inflight buffer */
67 #define INFLIGHT_ALIGNMENT 64
68
69 /* The version of inflight buffer */
70 #define INFLIGHT_VERSION 1
71
72 /* The version of the protocol we support */
73 #define VHOST_USER_VERSION 1
74 #define LIBVHOST_USER_DEBUG 0
75
76 #define DPRINT(...) \
77 do { \
78 if (LIBVHOST_USER_DEBUG) { \
79 fprintf(stderr, __VA_ARGS__); \
80 } \
81 } while (0)
82
83 static inline
84 bool has_feature(uint64_t features, unsigned int fbit)
85 {
86 assert(fbit < 64);
87 return !!(features & (1ULL << fbit));
88 }
89
90 static inline
91 bool vu_has_feature(VuDev *dev,
92 unsigned int fbit)
93 {
94 return has_feature(dev->features, fbit);
95 }
96
97 static inline bool vu_has_protocol_feature(VuDev *dev, unsigned int fbit)
98 {
99 return has_feature(dev->protocol_features, fbit);
100 }
101
102 static const char *
103 vu_request_to_string(unsigned int req)
104 {
105 #define REQ(req) [req] = #req
106 static const char *vu_request_str[] = {
107 REQ(VHOST_USER_NONE),
108 REQ(VHOST_USER_GET_FEATURES),
109 REQ(VHOST_USER_SET_FEATURES),
110 REQ(VHOST_USER_SET_OWNER),
111 REQ(VHOST_USER_RESET_OWNER),
112 REQ(VHOST_USER_SET_MEM_TABLE),
113 REQ(VHOST_USER_SET_LOG_BASE),
114 REQ(VHOST_USER_SET_LOG_FD),
115 REQ(VHOST_USER_SET_VRING_NUM),
116 REQ(VHOST_USER_SET_VRING_ADDR),
117 REQ(VHOST_USER_SET_VRING_BASE),
118 REQ(VHOST_USER_GET_VRING_BASE),
119 REQ(VHOST_USER_SET_VRING_KICK),
120 REQ(VHOST_USER_SET_VRING_CALL),
121 REQ(VHOST_USER_SET_VRING_ERR),
122 REQ(VHOST_USER_GET_PROTOCOL_FEATURES),
123 REQ(VHOST_USER_SET_PROTOCOL_FEATURES),
124 REQ(VHOST_USER_GET_QUEUE_NUM),
125 REQ(VHOST_USER_SET_VRING_ENABLE),
126 REQ(VHOST_USER_SEND_RARP),
127 REQ(VHOST_USER_NET_SET_MTU),
128 REQ(VHOST_USER_SET_SLAVE_REQ_FD),
129 REQ(VHOST_USER_IOTLB_MSG),
130 REQ(VHOST_USER_SET_VRING_ENDIAN),
131 REQ(VHOST_USER_GET_CONFIG),
132 REQ(VHOST_USER_SET_CONFIG),
133 REQ(VHOST_USER_POSTCOPY_ADVISE),
134 REQ(VHOST_USER_POSTCOPY_LISTEN),
135 REQ(VHOST_USER_POSTCOPY_END),
136 REQ(VHOST_USER_GET_INFLIGHT_FD),
137 REQ(VHOST_USER_SET_INFLIGHT_FD),
138 REQ(VHOST_USER_GPU_SET_SOCKET),
139 REQ(VHOST_USER_VRING_KICK),
140 REQ(VHOST_USER_GET_MAX_MEM_SLOTS),
141 REQ(VHOST_USER_ADD_MEM_REG),
142 REQ(VHOST_USER_REM_MEM_REG),
143 REQ(VHOST_USER_MAX),
144 };
145 #undef REQ
146
147 if (req < VHOST_USER_MAX) {
148 return vu_request_str[req];
149 } else {
150 return "unknown";
151 }
152 }
153
154 static void
155 vu_panic(VuDev *dev, const char *msg, ...)
156 {
157 char *buf = NULL;
158 va_list ap;
159
160 va_start(ap, msg);
161 if (vasprintf(&buf, msg, ap) < 0) {
162 buf = NULL;
163 }
164 va_end(ap);
165
166 dev->broken = true;
167 dev->panic(dev, buf);
168 free(buf);
169
170 /*
171 * FIXME:
172 * find a way to call virtio_error, or perhaps close the connection?
173 */
174 }
175
176 /* Translate guest physical address to our virtual address. */
177 void *
178 vu_gpa_to_va(VuDev *dev, uint64_t *plen, uint64_t guest_addr)
179 {
180 int i;
181
182 if (*plen == 0) {
183 return NULL;
184 }
185
186 /* Find matching memory region. */
187 for (i = 0; i < dev->nregions; i++) {
188 VuDevRegion *r = &dev->regions[i];
189
190 if ((guest_addr >= r->gpa) && (guest_addr < (r->gpa + r->size))) {
191 if ((guest_addr + *plen) > (r->gpa + r->size)) {
192 *plen = r->gpa + r->size - guest_addr;
193 }
194 return (void *)(uintptr_t)
195 guest_addr - r->gpa + r->mmap_addr + r->mmap_offset;
196 }
197 }
198
199 return NULL;
200 }
201
202 /* Translate qemu virtual address to our virtual address. */
203 static void *
204 qva_to_va(VuDev *dev, uint64_t qemu_addr)
205 {
206 int i;
207
208 /* Find matching memory region. */
209 for (i = 0; i < dev->nregions; i++) {
210 VuDevRegion *r = &dev->regions[i];
211
212 if ((qemu_addr >= r->qva) && (qemu_addr < (r->qva + r->size))) {
213 return (void *)(uintptr_t)
214 qemu_addr - r->qva + r->mmap_addr + r->mmap_offset;
215 }
216 }
217
218 return NULL;
219 }
220
221 static void
222 vmsg_close_fds(VhostUserMsg *vmsg)
223 {
224 int i;
225
226 for (i = 0; i < vmsg->fd_num; i++) {
227 close(vmsg->fds[i]);
228 }
229 }
230
231 /* Set reply payload.u64 and clear request flags and fd_num */
232 static void vmsg_set_reply_u64(VhostUserMsg *vmsg, uint64_t val)
233 {
234 vmsg->flags = 0; /* defaults will be set by vu_send_reply() */
235 vmsg->size = sizeof(vmsg->payload.u64);
236 vmsg->payload.u64 = val;
237 vmsg->fd_num = 0;
238 }
239
240 /* A test to see if we have userfault available */
241 static bool
242 have_userfault(void)
243 {
244 #if defined(__linux__) && defined(__NR_userfaultfd) &&\
245 defined(UFFD_FEATURE_MISSING_SHMEM) &&\
246 defined(UFFD_FEATURE_MISSING_HUGETLBFS)
247 /* Now test the kernel we're running on really has the features */
248 int ufd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK);
249 struct uffdio_api api_struct;
250 if (ufd < 0) {
251 return false;
252 }
253
254 api_struct.api = UFFD_API;
255 api_struct.features = UFFD_FEATURE_MISSING_SHMEM |
256 UFFD_FEATURE_MISSING_HUGETLBFS;
257 if (ioctl(ufd, UFFDIO_API, &api_struct)) {
258 close(ufd);
259 return false;
260 }
261 close(ufd);
262 return true;
263
264 #else
265 return false;
266 #endif
267 }
268
269 static bool
270 vu_message_read_default(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
271 {
272 char control[CMSG_SPACE(VHOST_MEMORY_BASELINE_NREGIONS * sizeof(int))] = {};
273 struct iovec iov = {
274 .iov_base = (char *)vmsg,
275 .iov_len = VHOST_USER_HDR_SIZE,
276 };
277 struct msghdr msg = {
278 .msg_iov = &iov,
279 .msg_iovlen = 1,
280 .msg_control = control,
281 .msg_controllen = sizeof(control),
282 };
283 size_t fd_size;
284 struct cmsghdr *cmsg;
285 int rc;
286
287 do {
288 rc = recvmsg(conn_fd, &msg, 0);
289 } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
290
291 if (rc < 0) {
292 vu_panic(dev, "Error while recvmsg: %s", strerror(errno));
293 return false;
294 }
295
296 vmsg->fd_num = 0;
297 for (cmsg = CMSG_FIRSTHDR(&msg);
298 cmsg != NULL;
299 cmsg = CMSG_NXTHDR(&msg, cmsg))
300 {
301 if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) {
302 fd_size = cmsg->cmsg_len - CMSG_LEN(0);
303 vmsg->fd_num = fd_size / sizeof(int);
304 memcpy(vmsg->fds, CMSG_DATA(cmsg), fd_size);
305 break;
306 }
307 }
308
309 if (vmsg->size > sizeof(vmsg->payload)) {
310 vu_panic(dev,
311 "Error: too big message request: %d, size: vmsg->size: %u, "
312 "while sizeof(vmsg->payload) = %zu\n",
313 vmsg->request, vmsg->size, sizeof(vmsg->payload));
314 goto fail;
315 }
316
317 if (vmsg->size) {
318 do {
319 rc = read(conn_fd, &vmsg->payload, vmsg->size);
320 } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
321
322 if (rc <= 0) {
323 vu_panic(dev, "Error while reading: %s", strerror(errno));
324 goto fail;
325 }
326
327 assert(rc == vmsg->size);
328 }
329
330 return true;
331
332 fail:
333 vmsg_close_fds(vmsg);
334
335 return false;
336 }
337
338 static bool
339 vu_message_write(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
340 {
341 int rc;
342 uint8_t *p = (uint8_t *)vmsg;
343 char control[CMSG_SPACE(VHOST_MEMORY_BASELINE_NREGIONS * sizeof(int))] = {};
344 struct iovec iov = {
345 .iov_base = (char *)vmsg,
346 .iov_len = VHOST_USER_HDR_SIZE,
347 };
348 struct msghdr msg = {
349 .msg_iov = &iov,
350 .msg_iovlen = 1,
351 .msg_control = control,
352 };
353 struct cmsghdr *cmsg;
354
355 memset(control, 0, sizeof(control));
356 assert(vmsg->fd_num <= VHOST_MEMORY_BASELINE_NREGIONS);
357 if (vmsg->fd_num > 0) {
358 size_t fdsize = vmsg->fd_num * sizeof(int);
359 msg.msg_controllen = CMSG_SPACE(fdsize);
360 cmsg = CMSG_FIRSTHDR(&msg);
361 cmsg->cmsg_len = CMSG_LEN(fdsize);
362 cmsg->cmsg_level = SOL_SOCKET;
363 cmsg->cmsg_type = SCM_RIGHTS;
364 memcpy(CMSG_DATA(cmsg), vmsg->fds, fdsize);
365 } else {
366 msg.msg_controllen = 0;
367 }
368
369 do {
370 rc = sendmsg(conn_fd, &msg, 0);
371 } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
372
373 if (vmsg->size) {
374 do {
375 if (vmsg->data) {
376 rc = write(conn_fd, vmsg->data, vmsg->size);
377 } else {
378 rc = write(conn_fd, p + VHOST_USER_HDR_SIZE, vmsg->size);
379 }
380 } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
381 }
382
383 if (rc <= 0) {
384 vu_panic(dev, "Error while writing: %s", strerror(errno));
385 return false;
386 }
387
388 return true;
389 }
390
391 static bool
392 vu_send_reply(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
393 {
394 /* Set the version in the flags when sending the reply */
395 vmsg->flags &= ~VHOST_USER_VERSION_MASK;
396 vmsg->flags |= VHOST_USER_VERSION;
397 vmsg->flags |= VHOST_USER_REPLY_MASK;
398
399 return vu_message_write(dev, conn_fd, vmsg);
400 }
401
402 /*
403 * Processes a reply on the slave channel.
404 * Entered with slave_mutex held and releases it before exit.
405 * Returns true on success.
406 */
407 static bool
408 vu_process_message_reply(VuDev *dev, const VhostUserMsg *vmsg)
409 {
410 VhostUserMsg msg_reply;
411 bool result = false;
412
413 if ((vmsg->flags & VHOST_USER_NEED_REPLY_MASK) == 0) {
414 result = true;
415 goto out;
416 }
417
418 if (!vu_message_read_default(dev, dev->slave_fd, &msg_reply)) {
419 goto out;
420 }
421
422 if (msg_reply.request != vmsg->request) {
423 DPRINT("Received unexpected msg type. Expected %d received %d",
424 vmsg->request, msg_reply.request);
425 goto out;
426 }
427
428 result = msg_reply.payload.u64 == 0;
429
430 out:
431 pthread_mutex_unlock(&dev->slave_mutex);
432 return result;
433 }
434
435 /* Kick the log_call_fd if required. */
436 static void
437 vu_log_kick(VuDev *dev)
438 {
439 if (dev->log_call_fd != -1) {
440 DPRINT("Kicking the QEMU's log...\n");
441 if (eventfd_write(dev->log_call_fd, 1) < 0) {
442 vu_panic(dev, "Error writing eventfd: %s", strerror(errno));
443 }
444 }
445 }
446
447 static void
448 vu_log_page(uint8_t *log_table, uint64_t page)
449 {
450 DPRINT("Logged dirty guest page: %"PRId64"\n", page);
451 qatomic_or(&log_table[page / 8], 1 << (page % 8));
452 }
453
454 static void
455 vu_log_write(VuDev *dev, uint64_t address, uint64_t length)
456 {
457 uint64_t page;
458
459 if (!(dev->features & (1ULL << VHOST_F_LOG_ALL)) ||
460 !dev->log_table || !length) {
461 return;
462 }
463
464 assert(dev->log_size > ((address + length - 1) / VHOST_LOG_PAGE / 8));
465
466 page = address / VHOST_LOG_PAGE;
467 while (page * VHOST_LOG_PAGE < address + length) {
468 vu_log_page(dev->log_table, page);
469 page += 1;
470 }
471
472 vu_log_kick(dev);
473 }
474
475 static void
476 vu_kick_cb(VuDev *dev, int condition, void *data)
477 {
478 int index = (intptr_t)data;
479 VuVirtq *vq = &dev->vq[index];
480 int sock = vq->kick_fd;
481 eventfd_t kick_data;
482 ssize_t rc;
483
484 rc = eventfd_read(sock, &kick_data);
485 if (rc == -1) {
486 vu_panic(dev, "kick eventfd_read(): %s", strerror(errno));
487 dev->remove_watch(dev, dev->vq[index].kick_fd);
488 } else {
489 DPRINT("Got kick_data: %016"PRIx64" handler:%p idx:%d\n",
490 kick_data, vq->handler, index);
491 if (vq->handler) {
492 vq->handler(dev, index);
493 }
494 }
495 }
496
497 static bool
498 vu_get_features_exec(VuDev *dev, VhostUserMsg *vmsg)
499 {
500 vmsg->payload.u64 =
501 /*
502 * The following VIRTIO feature bits are supported by our virtqueue
503 * implementation:
504 */
505 1ULL << VIRTIO_F_NOTIFY_ON_EMPTY |
506 1ULL << VIRTIO_RING_F_INDIRECT_DESC |
507 1ULL << VIRTIO_RING_F_EVENT_IDX |
508 1ULL << VIRTIO_F_VERSION_1 |
509
510 /* vhost-user feature bits */
511 1ULL << VHOST_F_LOG_ALL |
512 1ULL << VHOST_USER_F_PROTOCOL_FEATURES;
513
514 if (dev->iface->get_features) {
515 vmsg->payload.u64 |= dev->iface->get_features(dev);
516 }
517
518 vmsg->size = sizeof(vmsg->payload.u64);
519 vmsg->fd_num = 0;
520
521 DPRINT("Sending back to guest u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
522
523 return true;
524 }
525
526 static void
527 vu_set_enable_all_rings(VuDev *dev, bool enabled)
528 {
529 uint16_t i;
530
531 for (i = 0; i < dev->max_queues; i++) {
532 dev->vq[i].enable = enabled;
533 }
534 }
535
536 static bool
537 vu_set_features_exec(VuDev *dev, VhostUserMsg *vmsg)
538 {
539 DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
540
541 dev->features = vmsg->payload.u64;
542 if (!vu_has_feature(dev, VIRTIO_F_VERSION_1)) {
543 /*
544 * We only support devices conforming to VIRTIO 1.0 or
545 * later
546 */
547 vu_panic(dev, "virtio legacy devices aren't supported by libvhost-user");
548 return false;
549 }
550
551 if (!(dev->features & VHOST_USER_F_PROTOCOL_FEATURES)) {
552 vu_set_enable_all_rings(dev, true);
553 }
554
555 if (dev->iface->set_features) {
556 dev->iface->set_features(dev, dev->features);
557 }
558
559 return false;
560 }
561
562 static bool
563 vu_set_owner_exec(VuDev *dev, VhostUserMsg *vmsg)
564 {
565 return false;
566 }
567
568 static void
569 vu_close_log(VuDev *dev)
570 {
571 if (dev->log_table) {
572 if (munmap(dev->log_table, dev->log_size) != 0) {
573 perror("close log munmap() error");
574 }
575
576 dev->log_table = NULL;
577 }
578 if (dev->log_call_fd != -1) {
579 close(dev->log_call_fd);
580 dev->log_call_fd = -1;
581 }
582 }
583
584 static bool
585 vu_reset_device_exec(VuDev *dev, VhostUserMsg *vmsg)
586 {
587 vu_set_enable_all_rings(dev, false);
588
589 return false;
590 }
591
592 static bool
593 map_ring(VuDev *dev, VuVirtq *vq)
594 {
595 vq->vring.desc = qva_to_va(dev, vq->vra.desc_user_addr);
596 vq->vring.used = qva_to_va(dev, vq->vra.used_user_addr);
597 vq->vring.avail = qva_to_va(dev, vq->vra.avail_user_addr);
598
599 DPRINT("Setting virtq addresses:\n");
600 DPRINT(" vring_desc at %p\n", vq->vring.desc);
601 DPRINT(" vring_used at %p\n", vq->vring.used);
602 DPRINT(" vring_avail at %p\n", vq->vring.avail);
603
604 return !(vq->vring.desc && vq->vring.used && vq->vring.avail);
605 }
606
607 static bool
608 generate_faults(VuDev *dev) {
609 int i;
610 for (i = 0; i < dev->nregions; i++) {
611 VuDevRegion *dev_region = &dev->regions[i];
612 int ret;
613 #ifdef UFFDIO_REGISTER
614 /*
615 * We should already have an open ufd. Mark each memory
616 * range as ufd.
617 * Discard any mapping we have here; note I can't use MADV_REMOVE
618 * or fallocate to make the hole since I don't want to lose
619 * data that's already arrived in the shared process.
620 * TODO: How to do hugepage
621 */
622 ret = madvise((void *)(uintptr_t)dev_region->mmap_addr,
623 dev_region->size + dev_region->mmap_offset,
624 MADV_DONTNEED);
625 if (ret) {
626 fprintf(stderr,
627 "%s: Failed to madvise(DONTNEED) region %d: %s\n",
628 __func__, i, strerror(errno));
629 }
630 /*
631 * Turn off transparent hugepages so we dont get lose wakeups
632 * in neighbouring pages.
633 * TODO: Turn this backon later.
634 */
635 ret = madvise((void *)(uintptr_t)dev_region->mmap_addr,
636 dev_region->size + dev_region->mmap_offset,
637 MADV_NOHUGEPAGE);
638 if (ret) {
639 /*
640 * Note: This can happen legally on kernels that are configured
641 * without madvise'able hugepages
642 */
643 fprintf(stderr,
644 "%s: Failed to madvise(NOHUGEPAGE) region %d: %s\n",
645 __func__, i, strerror(errno));
646 }
647 struct uffdio_register reg_struct;
648 reg_struct.range.start = (uintptr_t)dev_region->mmap_addr;
649 reg_struct.range.len = dev_region->size + dev_region->mmap_offset;
650 reg_struct.mode = UFFDIO_REGISTER_MODE_MISSING;
651
652 if (ioctl(dev->postcopy_ufd, UFFDIO_REGISTER, &reg_struct)) {
653 vu_panic(dev, "%s: Failed to userfault region %d "
654 "@%p + size:%zx offset: %zx: (ufd=%d)%s\n",
655 __func__, i,
656 dev_region->mmap_addr,
657 dev_region->size, dev_region->mmap_offset,
658 dev->postcopy_ufd, strerror(errno));
659 return false;
660 }
661 if (!(reg_struct.ioctls & ((__u64)1 << _UFFDIO_COPY))) {
662 vu_panic(dev, "%s Region (%d) doesn't support COPY",
663 __func__, i);
664 return false;
665 }
666 DPRINT("%s: region %d: Registered userfault for %"
667 PRIx64 " + %" PRIx64 "\n", __func__, i,
668 (uint64_t)reg_struct.range.start,
669 (uint64_t)reg_struct.range.len);
670 /* Now it's registered we can let the client at it */
671 if (mprotect((void *)(uintptr_t)dev_region->mmap_addr,
672 dev_region->size + dev_region->mmap_offset,
673 PROT_READ | PROT_WRITE)) {
674 vu_panic(dev, "failed to mprotect region %d for postcopy (%s)",
675 i, strerror(errno));
676 return false;
677 }
678 /* TODO: Stash 'zero' support flags somewhere */
679 #endif
680 }
681
682 return true;
683 }
684
685 static bool
686 vu_add_mem_reg(VuDev *dev, VhostUserMsg *vmsg) {
687 int i;
688 bool track_ramblocks = dev->postcopy_listening;
689 VhostUserMemoryRegion m = vmsg->payload.memreg.region, *msg_region = &m;
690 VuDevRegion *dev_region = &dev->regions[dev->nregions];
691 void *mmap_addr;
692
693 /*
694 * If we are in postcopy mode and we receive a u64 payload with a 0 value
695 * we know all the postcopy client bases have been received, and we
696 * should start generating faults.
697 */
698 if (track_ramblocks &&
699 vmsg->size == sizeof(vmsg->payload.u64) &&
700 vmsg->payload.u64 == 0) {
701 (void)generate_faults(dev);
702 return false;
703 }
704
705 DPRINT("Adding region: %u\n", dev->nregions);
706 DPRINT(" guest_phys_addr: 0x%016"PRIx64"\n",
707 msg_region->guest_phys_addr);
708 DPRINT(" memory_size: 0x%016"PRIx64"\n",
709 msg_region->memory_size);
710 DPRINT(" userspace_addr 0x%016"PRIx64"\n",
711 msg_region->userspace_addr);
712 DPRINT(" mmap_offset 0x%016"PRIx64"\n",
713 msg_region->mmap_offset);
714
715 dev_region->gpa = msg_region->guest_phys_addr;
716 dev_region->size = msg_region->memory_size;
717 dev_region->qva = msg_region->userspace_addr;
718 dev_region->mmap_offset = msg_region->mmap_offset;
719
720 /*
721 * We don't use offset argument of mmap() since the
722 * mapped address has to be page aligned, and we use huge
723 * pages.
724 */
725 if (track_ramblocks) {
726 /*
727 * In postcopy we're using PROT_NONE here to catch anyone
728 * accessing it before we userfault.
729 */
730 mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset,
731 PROT_NONE, MAP_SHARED,
732 vmsg->fds[0], 0);
733 } else {
734 mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset,
735 PROT_READ | PROT_WRITE, MAP_SHARED, vmsg->fds[0],
736 0);
737 }
738
739 if (mmap_addr == MAP_FAILED) {
740 vu_panic(dev, "region mmap error: %s", strerror(errno));
741 } else {
742 dev_region->mmap_addr = (uint64_t)(uintptr_t)mmap_addr;
743 DPRINT(" mmap_addr: 0x%016"PRIx64"\n",
744 dev_region->mmap_addr);
745 }
746
747 close(vmsg->fds[0]);
748
749 if (track_ramblocks) {
750 /*
751 * Return the address to QEMU so that it can translate the ufd
752 * fault addresses back.
753 */
754 msg_region->userspace_addr = (uintptr_t)(mmap_addr +
755 dev_region->mmap_offset);
756
757 /* Send the message back to qemu with the addresses filled in. */
758 vmsg->fd_num = 0;
759 if (!vu_send_reply(dev, dev->sock, vmsg)) {
760 vu_panic(dev, "failed to respond to add-mem-region for postcopy");
761 return false;
762 }
763
764 DPRINT("Successfully added new region in postcopy\n");
765 dev->nregions++;
766 return false;
767
768 } else {
769 for (i = 0; i < dev->max_queues; i++) {
770 if (dev->vq[i].vring.desc) {
771 if (map_ring(dev, &dev->vq[i])) {
772 vu_panic(dev, "remapping queue %d for new memory region",
773 i);
774 }
775 }
776 }
777
778 DPRINT("Successfully added new region\n");
779 dev->nregions++;
780 vmsg_set_reply_u64(vmsg, 0);
781 return true;
782 }
783 }
784
785 static inline bool reg_equal(VuDevRegion *vudev_reg,
786 VhostUserMemoryRegion *msg_reg)
787 {
788 if (vudev_reg->gpa == msg_reg->guest_phys_addr &&
789 vudev_reg->qva == msg_reg->userspace_addr &&
790 vudev_reg->size == msg_reg->memory_size) {
791 return true;
792 }
793
794 return false;
795 }
796
797 static bool
798 vu_rem_mem_reg(VuDev *dev, VhostUserMsg *vmsg) {
799 int i, j;
800 bool found = false;
801 VuDevRegion shadow_regions[VHOST_USER_MAX_RAM_SLOTS] = {};
802 VhostUserMemoryRegion m = vmsg->payload.memreg.region, *msg_region = &m;
803
804 DPRINT("Removing region:\n");
805 DPRINT(" guest_phys_addr: 0x%016"PRIx64"\n",
806 msg_region->guest_phys_addr);
807 DPRINT(" memory_size: 0x%016"PRIx64"\n",
808 msg_region->memory_size);
809 DPRINT(" userspace_addr 0x%016"PRIx64"\n",
810 msg_region->userspace_addr);
811 DPRINT(" mmap_offset 0x%016"PRIx64"\n",
812 msg_region->mmap_offset);
813
814 for (i = 0, j = 0; i < dev->nregions; i++) {
815 if (!reg_equal(&dev->regions[i], msg_region)) {
816 shadow_regions[j].gpa = dev->regions[i].gpa;
817 shadow_regions[j].size = dev->regions[i].size;
818 shadow_regions[j].qva = dev->regions[i].qva;
819 shadow_regions[j].mmap_addr = dev->regions[i].mmap_addr;
820 shadow_regions[j].mmap_offset = dev->regions[i].mmap_offset;
821 j++;
822 } else {
823 found = true;
824 VuDevRegion *r = &dev->regions[i];
825 void *m = (void *) (uintptr_t) r->mmap_addr;
826
827 if (m) {
828 munmap(m, r->size + r->mmap_offset);
829 }
830 }
831 }
832
833 if (found) {
834 memcpy(dev->regions, shadow_regions,
835 sizeof(VuDevRegion) * VHOST_USER_MAX_RAM_SLOTS);
836 DPRINT("Successfully removed a region\n");
837 dev->nregions--;
838 vmsg_set_reply_u64(vmsg, 0);
839 } else {
840 vu_panic(dev, "Specified region not found\n");
841 }
842
843 return true;
844 }
845
846 static bool
847 vu_set_mem_table_exec_postcopy(VuDev *dev, VhostUserMsg *vmsg)
848 {
849 int i;
850 VhostUserMemory m = vmsg->payload.memory, *memory = &m;
851 dev->nregions = memory->nregions;
852
853 DPRINT("Nregions: %u\n", memory->nregions);
854 for (i = 0; i < dev->nregions; i++) {
855 void *mmap_addr;
856 VhostUserMemoryRegion *msg_region = &memory->regions[i];
857 VuDevRegion *dev_region = &dev->regions[i];
858
859 DPRINT("Region %d\n", i);
860 DPRINT(" guest_phys_addr: 0x%016"PRIx64"\n",
861 msg_region->guest_phys_addr);
862 DPRINT(" memory_size: 0x%016"PRIx64"\n",
863 msg_region->memory_size);
864 DPRINT(" userspace_addr 0x%016"PRIx64"\n",
865 msg_region->userspace_addr);
866 DPRINT(" mmap_offset 0x%016"PRIx64"\n",
867 msg_region->mmap_offset);
868
869 dev_region->gpa = msg_region->guest_phys_addr;
870 dev_region->size = msg_region->memory_size;
871 dev_region->qva = msg_region->userspace_addr;
872 dev_region->mmap_offset = msg_region->mmap_offset;
873
874 /* We don't use offset argument of mmap() since the
875 * mapped address has to be page aligned, and we use huge
876 * pages.
877 * In postcopy we're using PROT_NONE here to catch anyone
878 * accessing it before we userfault
879 */
880 mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset,
881 PROT_NONE, MAP_SHARED,
882 vmsg->fds[i], 0);
883
884 if (mmap_addr == MAP_FAILED) {
885 vu_panic(dev, "region mmap error: %s", strerror(errno));
886 } else {
887 dev_region->mmap_addr = (uint64_t)(uintptr_t)mmap_addr;
888 DPRINT(" mmap_addr: 0x%016"PRIx64"\n",
889 dev_region->mmap_addr);
890 }
891
892 /* Return the address to QEMU so that it can translate the ufd
893 * fault addresses back.
894 */
895 msg_region->userspace_addr = (uintptr_t)(mmap_addr +
896 dev_region->mmap_offset);
897 close(vmsg->fds[i]);
898 }
899
900 /* Send the message back to qemu with the addresses filled in */
901 vmsg->fd_num = 0;
902 if (!vu_send_reply(dev, dev->sock, vmsg)) {
903 vu_panic(dev, "failed to respond to set-mem-table for postcopy");
904 return false;
905 }
906
907 /* Wait for QEMU to confirm that it's registered the handler for the
908 * faults.
909 */
910 if (!dev->read_msg(dev, dev->sock, vmsg) ||
911 vmsg->size != sizeof(vmsg->payload.u64) ||
912 vmsg->payload.u64 != 0) {
913 vu_panic(dev, "failed to receive valid ack for postcopy set-mem-table");
914 return false;
915 }
916
917 /* OK, now we can go and register the memory and generate faults */
918 (void)generate_faults(dev);
919
920 return false;
921 }
922
923 static bool
924 vu_set_mem_table_exec(VuDev *dev, VhostUserMsg *vmsg)
925 {
926 int i;
927 VhostUserMemory m = vmsg->payload.memory, *memory = &m;
928
929 for (i = 0; i < dev->nregions; i++) {
930 VuDevRegion *r = &dev->regions[i];
931 void *m = (void *) (uintptr_t) r->mmap_addr;
932
933 if (m) {
934 munmap(m, r->size + r->mmap_offset);
935 }
936 }
937 dev->nregions = memory->nregions;
938
939 if (dev->postcopy_listening) {
940 return vu_set_mem_table_exec_postcopy(dev, vmsg);
941 }
942
943 DPRINT("Nregions: %u\n", memory->nregions);
944 for (i = 0; i < dev->nregions; i++) {
945 void *mmap_addr;
946 VhostUserMemoryRegion *msg_region = &memory->regions[i];
947 VuDevRegion *dev_region = &dev->regions[i];
948
949 DPRINT("Region %d\n", i);
950 DPRINT(" guest_phys_addr: 0x%016"PRIx64"\n",
951 msg_region->guest_phys_addr);
952 DPRINT(" memory_size: 0x%016"PRIx64"\n",
953 msg_region->memory_size);
954 DPRINT(" userspace_addr 0x%016"PRIx64"\n",
955 msg_region->userspace_addr);
956 DPRINT(" mmap_offset 0x%016"PRIx64"\n",
957 msg_region->mmap_offset);
958
959 dev_region->gpa = msg_region->guest_phys_addr;
960 dev_region->size = msg_region->memory_size;
961 dev_region->qva = msg_region->userspace_addr;
962 dev_region->mmap_offset = msg_region->mmap_offset;
963
964 /* We don't use offset argument of mmap() since the
965 * mapped address has to be page aligned, and we use huge
966 * pages. */
967 mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset,
968 PROT_READ | PROT_WRITE, MAP_SHARED,
969 vmsg->fds[i], 0);
970
971 if (mmap_addr == MAP_FAILED) {
972 vu_panic(dev, "region mmap error: %s", strerror(errno));
973 } else {
974 dev_region->mmap_addr = (uint64_t)(uintptr_t)mmap_addr;
975 DPRINT(" mmap_addr: 0x%016"PRIx64"\n",
976 dev_region->mmap_addr);
977 }
978
979 close(vmsg->fds[i]);
980 }
981
982 for (i = 0; i < dev->max_queues; i++) {
983 if (dev->vq[i].vring.desc) {
984 if (map_ring(dev, &dev->vq[i])) {
985 vu_panic(dev, "remapping queue %d during setmemtable", i);
986 }
987 }
988 }
989
990 return false;
991 }
992
993 static bool
994 vu_set_log_base_exec(VuDev *dev, VhostUserMsg *vmsg)
995 {
996 int fd;
997 uint64_t log_mmap_size, log_mmap_offset;
998 void *rc;
999
1000 if (vmsg->fd_num != 1 ||
1001 vmsg->size != sizeof(vmsg->payload.log)) {
1002 vu_panic(dev, "Invalid log_base message");
1003 return true;
1004 }
1005
1006 fd = vmsg->fds[0];
1007 log_mmap_offset = vmsg->payload.log.mmap_offset;
1008 log_mmap_size = vmsg->payload.log.mmap_size;
1009 DPRINT("Log mmap_offset: %"PRId64"\n", log_mmap_offset);
1010 DPRINT("Log mmap_size: %"PRId64"\n", log_mmap_size);
1011
1012 rc = mmap(0, log_mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd,
1013 log_mmap_offset);
1014 close(fd);
1015 if (rc == MAP_FAILED) {
1016 perror("log mmap error");
1017 }
1018
1019 if (dev->log_table) {
1020 munmap(dev->log_table, dev->log_size);
1021 }
1022 dev->log_table = rc;
1023 dev->log_size = log_mmap_size;
1024
1025 vmsg->size = sizeof(vmsg->payload.u64);
1026 vmsg->fd_num = 0;
1027
1028 return true;
1029 }
1030
1031 static bool
1032 vu_set_log_fd_exec(VuDev *dev, VhostUserMsg *vmsg)
1033 {
1034 if (vmsg->fd_num != 1) {
1035 vu_panic(dev, "Invalid log_fd message");
1036 return false;
1037 }
1038
1039 if (dev->log_call_fd != -1) {
1040 close(dev->log_call_fd);
1041 }
1042 dev->log_call_fd = vmsg->fds[0];
1043 DPRINT("Got log_call_fd: %d\n", vmsg->fds[0]);
1044
1045 return false;
1046 }
1047
1048 static bool
1049 vu_set_vring_num_exec(VuDev *dev, VhostUserMsg *vmsg)
1050 {
1051 unsigned int index = vmsg->payload.state.index;
1052 unsigned int num = vmsg->payload.state.num;
1053
1054 DPRINT("State.index: %u\n", index);
1055 DPRINT("State.num: %u\n", num);
1056 dev->vq[index].vring.num = num;
1057
1058 return false;
1059 }
1060
1061 static bool
1062 vu_set_vring_addr_exec(VuDev *dev, VhostUserMsg *vmsg)
1063 {
1064 struct vhost_vring_addr addr = vmsg->payload.addr, *vra = &addr;
1065 unsigned int index = vra->index;
1066 VuVirtq *vq = &dev->vq[index];
1067
1068 DPRINT("vhost_vring_addr:\n");
1069 DPRINT(" index: %d\n", vra->index);
1070 DPRINT(" flags: %d\n", vra->flags);
1071 DPRINT(" desc_user_addr: 0x%016" PRIx64 "\n", (uint64_t)vra->desc_user_addr);
1072 DPRINT(" used_user_addr: 0x%016" PRIx64 "\n", (uint64_t)vra->used_user_addr);
1073 DPRINT(" avail_user_addr: 0x%016" PRIx64 "\n", (uint64_t)vra->avail_user_addr);
1074 DPRINT(" log_guest_addr: 0x%016" PRIx64 "\n", (uint64_t)vra->log_guest_addr);
1075
1076 vq->vra = *vra;
1077 vq->vring.flags = vra->flags;
1078 vq->vring.log_guest_addr = vra->log_guest_addr;
1079
1080
1081 if (map_ring(dev, vq)) {
1082 vu_panic(dev, "Invalid vring_addr message");
1083 return false;
1084 }
1085
1086 vq->used_idx = le16toh(vq->vring.used->idx);
1087
1088 if (vq->last_avail_idx != vq->used_idx) {
1089 bool resume = dev->iface->queue_is_processed_in_order &&
1090 dev->iface->queue_is_processed_in_order(dev, index);
1091
1092 DPRINT("Last avail index != used index: %u != %u%s\n",
1093 vq->last_avail_idx, vq->used_idx,
1094 resume ? ", resuming" : "");
1095
1096 if (resume) {
1097 vq->shadow_avail_idx = vq->last_avail_idx = vq->used_idx;
1098 }
1099 }
1100
1101 return false;
1102 }
1103
1104 static bool
1105 vu_set_vring_base_exec(VuDev *dev, VhostUserMsg *vmsg)
1106 {
1107 unsigned int index = vmsg->payload.state.index;
1108 unsigned int num = vmsg->payload.state.num;
1109
1110 DPRINT("State.index: %u\n", index);
1111 DPRINT("State.num: %u\n", num);
1112 dev->vq[index].shadow_avail_idx = dev->vq[index].last_avail_idx = num;
1113
1114 return false;
1115 }
1116
1117 static bool
1118 vu_get_vring_base_exec(VuDev *dev, VhostUserMsg *vmsg)
1119 {
1120 unsigned int index = vmsg->payload.state.index;
1121
1122 DPRINT("State.index: %u\n", index);
1123 vmsg->payload.state.num = dev->vq[index].last_avail_idx;
1124 vmsg->size = sizeof(vmsg->payload.state);
1125
1126 dev->vq[index].started = false;
1127 if (dev->iface->queue_set_started) {
1128 dev->iface->queue_set_started(dev, index, false);
1129 }
1130
1131 if (dev->vq[index].call_fd != -1) {
1132 close(dev->vq[index].call_fd);
1133 dev->vq[index].call_fd = -1;
1134 }
1135 if (dev->vq[index].kick_fd != -1) {
1136 dev->remove_watch(dev, dev->vq[index].kick_fd);
1137 close(dev->vq[index].kick_fd);
1138 dev->vq[index].kick_fd = -1;
1139 }
1140
1141 return true;
1142 }
1143
1144 static bool
1145 vu_check_queue_msg_file(VuDev *dev, VhostUserMsg *vmsg)
1146 {
1147 int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
1148 bool nofd = vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK;
1149
1150 if (index >= dev->max_queues) {
1151 vmsg_close_fds(vmsg);
1152 vu_panic(dev, "Invalid queue index: %u", index);
1153 return false;
1154 }
1155
1156 if (nofd) {
1157 vmsg_close_fds(vmsg);
1158 return true;
1159 }
1160
1161 if (vmsg->fd_num != 1) {
1162 vmsg_close_fds(vmsg);
1163 vu_panic(dev, "Invalid fds in request: %d", vmsg->request);
1164 return false;
1165 }
1166
1167 return true;
1168 }
1169
1170 static int
1171 inflight_desc_compare(const void *a, const void *b)
1172 {
1173 VuVirtqInflightDesc *desc0 = (VuVirtqInflightDesc *)a,
1174 *desc1 = (VuVirtqInflightDesc *)b;
1175
1176 if (desc1->counter > desc0->counter &&
1177 (desc1->counter - desc0->counter) < VIRTQUEUE_MAX_SIZE * 2) {
1178 return 1;
1179 }
1180
1181 return -1;
1182 }
1183
1184 static int
1185 vu_check_queue_inflights(VuDev *dev, VuVirtq *vq)
1186 {
1187 int i = 0;
1188
1189 if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
1190 return 0;
1191 }
1192
1193 if (unlikely(!vq->inflight)) {
1194 return -1;
1195 }
1196
1197 if (unlikely(!vq->inflight->version)) {
1198 /* initialize the buffer */
1199 vq->inflight->version = INFLIGHT_VERSION;
1200 return 0;
1201 }
1202
1203 vq->used_idx = le16toh(vq->vring.used->idx);
1204 vq->resubmit_num = 0;
1205 vq->resubmit_list = NULL;
1206 vq->counter = 0;
1207
1208 if (unlikely(vq->inflight->used_idx != vq->used_idx)) {
1209 vq->inflight->desc[vq->inflight->last_batch_head].inflight = 0;
1210
1211 barrier();
1212
1213 vq->inflight->used_idx = vq->used_idx;
1214 }
1215
1216 for (i = 0; i < vq->inflight->desc_num; i++) {
1217 if (vq->inflight->desc[i].inflight == 1) {
1218 vq->inuse++;
1219 }
1220 }
1221
1222 vq->shadow_avail_idx = vq->last_avail_idx = vq->inuse + vq->used_idx;
1223
1224 if (vq->inuse) {
1225 vq->resubmit_list = calloc(vq->inuse, sizeof(VuVirtqInflightDesc));
1226 if (!vq->resubmit_list) {
1227 return -1;
1228 }
1229
1230 for (i = 0; i < vq->inflight->desc_num; i++) {
1231 if (vq->inflight->desc[i].inflight) {
1232 vq->resubmit_list[vq->resubmit_num].index = i;
1233 vq->resubmit_list[vq->resubmit_num].counter =
1234 vq->inflight->desc[i].counter;
1235 vq->resubmit_num++;
1236 }
1237 }
1238
1239 if (vq->resubmit_num > 1) {
1240 qsort(vq->resubmit_list, vq->resubmit_num,
1241 sizeof(VuVirtqInflightDesc), inflight_desc_compare);
1242 }
1243 vq->counter = vq->resubmit_list[0].counter + 1;
1244 }
1245
1246 /* in case of I/O hang after reconnecting */
1247 if (eventfd_write(vq->kick_fd, 1)) {
1248 return -1;
1249 }
1250
1251 return 0;
1252 }
1253
1254 static bool
1255 vu_set_vring_kick_exec(VuDev *dev, VhostUserMsg *vmsg)
1256 {
1257 int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
1258 bool nofd = vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK;
1259
1260 DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
1261
1262 if (!vu_check_queue_msg_file(dev, vmsg)) {
1263 return false;
1264 }
1265
1266 if (dev->vq[index].kick_fd != -1) {
1267 dev->remove_watch(dev, dev->vq[index].kick_fd);
1268 close(dev->vq[index].kick_fd);
1269 dev->vq[index].kick_fd = -1;
1270 }
1271
1272 dev->vq[index].kick_fd = nofd ? -1 : vmsg->fds[0];
1273 DPRINT("Got kick_fd: %d for vq: %d\n", dev->vq[index].kick_fd, index);
1274
1275 dev->vq[index].started = true;
1276 if (dev->iface->queue_set_started) {
1277 dev->iface->queue_set_started(dev, index, true);
1278 }
1279
1280 if (dev->vq[index].kick_fd != -1 && dev->vq[index].handler) {
1281 dev->set_watch(dev, dev->vq[index].kick_fd, VU_WATCH_IN,
1282 vu_kick_cb, (void *)(long)index);
1283
1284 DPRINT("Waiting for kicks on fd: %d for vq: %d\n",
1285 dev->vq[index].kick_fd, index);
1286 }
1287
1288 if (vu_check_queue_inflights(dev, &dev->vq[index])) {
1289 vu_panic(dev, "Failed to check inflights for vq: %d\n", index);
1290 }
1291
1292 return false;
1293 }
1294
1295 void vu_set_queue_handler(VuDev *dev, VuVirtq *vq,
1296 vu_queue_handler_cb handler)
1297 {
1298 int qidx = vq - dev->vq;
1299
1300 vq->handler = handler;
1301 if (vq->kick_fd >= 0) {
1302 if (handler) {
1303 dev->set_watch(dev, vq->kick_fd, VU_WATCH_IN,
1304 vu_kick_cb, (void *)(long)qidx);
1305 } else {
1306 dev->remove_watch(dev, vq->kick_fd);
1307 }
1308 }
1309 }
1310
1311 bool vu_set_queue_host_notifier(VuDev *dev, VuVirtq *vq, int fd,
1312 int size, int offset)
1313 {
1314 int qidx = vq - dev->vq;
1315 int fd_num = 0;
1316 VhostUserMsg vmsg = {
1317 .request = VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG,
1318 .flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
1319 .size = sizeof(vmsg.payload.area),
1320 .payload.area = {
1321 .u64 = qidx & VHOST_USER_VRING_IDX_MASK,
1322 .size = size,
1323 .offset = offset,
1324 },
1325 };
1326
1327 if (fd == -1) {
1328 vmsg.payload.area.u64 |= VHOST_USER_VRING_NOFD_MASK;
1329 } else {
1330 vmsg.fds[fd_num++] = fd;
1331 }
1332
1333 vmsg.fd_num = fd_num;
1334
1335 if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD)) {
1336 return false;
1337 }
1338
1339 pthread_mutex_lock(&dev->slave_mutex);
1340 if (!vu_message_write(dev, dev->slave_fd, &vmsg)) {
1341 pthread_mutex_unlock(&dev->slave_mutex);
1342 return false;
1343 }
1344
1345 /* Also unlocks the slave_mutex */
1346 return vu_process_message_reply(dev, &vmsg);
1347 }
1348
1349 static bool
1350 vu_set_vring_call_exec(VuDev *dev, VhostUserMsg *vmsg)
1351 {
1352 int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
1353 bool nofd = vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK;
1354
1355 DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
1356
1357 if (!vu_check_queue_msg_file(dev, vmsg)) {
1358 return false;
1359 }
1360
1361 if (dev->vq[index].call_fd != -1) {
1362 close(dev->vq[index].call_fd);
1363 dev->vq[index].call_fd = -1;
1364 }
1365
1366 dev->vq[index].call_fd = nofd ? -1 : vmsg->fds[0];
1367
1368 /* in case of I/O hang after reconnecting */
1369 if (dev->vq[index].call_fd != -1 && eventfd_write(vmsg->fds[0], 1)) {
1370 return -1;
1371 }
1372
1373 DPRINT("Got call_fd: %d for vq: %d\n", dev->vq[index].call_fd, index);
1374
1375 return false;
1376 }
1377
1378 static bool
1379 vu_set_vring_err_exec(VuDev *dev, VhostUserMsg *vmsg)
1380 {
1381 int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
1382 bool nofd = vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK;
1383
1384 DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
1385
1386 if (!vu_check_queue_msg_file(dev, vmsg)) {
1387 return false;
1388 }
1389
1390 if (dev->vq[index].err_fd != -1) {
1391 close(dev->vq[index].err_fd);
1392 dev->vq[index].err_fd = -1;
1393 }
1394
1395 dev->vq[index].err_fd = nofd ? -1 : vmsg->fds[0];
1396
1397 return false;
1398 }
1399
1400 static bool
1401 vu_get_protocol_features_exec(VuDev *dev, VhostUserMsg *vmsg)
1402 {
1403 /*
1404 * Note that we support, but intentionally do not set,
1405 * VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS. This means that
1406 * a device implementation can return it in its callback
1407 * (get_protocol_features) if it wants to use this for
1408 * simulation, but it is otherwise not desirable (if even
1409 * implemented by the master.)
1410 */
1411 uint64_t features = 1ULL << VHOST_USER_PROTOCOL_F_MQ |
1412 1ULL << VHOST_USER_PROTOCOL_F_LOG_SHMFD |
1413 1ULL << VHOST_USER_PROTOCOL_F_SLAVE_REQ |
1414 1ULL << VHOST_USER_PROTOCOL_F_HOST_NOTIFIER |
1415 1ULL << VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD |
1416 1ULL << VHOST_USER_PROTOCOL_F_REPLY_ACK |
1417 1ULL << VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS;
1418
1419 if (have_userfault()) {
1420 features |= 1ULL << VHOST_USER_PROTOCOL_F_PAGEFAULT;
1421 }
1422
1423 if (dev->iface->get_config && dev->iface->set_config) {
1424 features |= 1ULL << VHOST_USER_PROTOCOL_F_CONFIG;
1425 }
1426
1427 if (dev->iface->get_protocol_features) {
1428 features |= dev->iface->get_protocol_features(dev);
1429 }
1430
1431 vmsg_set_reply_u64(vmsg, features);
1432 return true;
1433 }
1434
1435 static bool
1436 vu_set_protocol_features_exec(VuDev *dev, VhostUserMsg *vmsg)
1437 {
1438 uint64_t features = vmsg->payload.u64;
1439
1440 DPRINT("u64: 0x%016"PRIx64"\n", features);
1441
1442 dev->protocol_features = vmsg->payload.u64;
1443
1444 if (vu_has_protocol_feature(dev,
1445 VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS) &&
1446 (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_SLAVE_REQ) ||
1447 !vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_REPLY_ACK))) {
1448 /*
1449 * The use case for using messages for kick/call is simulation, to make
1450 * the kick and call synchronous. To actually get that behaviour, both
1451 * of the other features are required.
1452 * Theoretically, one could use only kick messages, or do them without
1453 * having F_REPLY_ACK, but too many (possibly pending) messages on the
1454 * socket will eventually cause the master to hang, to avoid this in
1455 * scenarios where not desired enforce that the settings are in a way
1456 * that actually enables the simulation case.
1457 */
1458 vu_panic(dev,
1459 "F_IN_BAND_NOTIFICATIONS requires F_SLAVE_REQ && F_REPLY_ACK");
1460 return false;
1461 }
1462
1463 if (dev->iface->set_protocol_features) {
1464 dev->iface->set_protocol_features(dev, features);
1465 }
1466
1467 return false;
1468 }
1469
1470 static bool
1471 vu_get_queue_num_exec(VuDev *dev, VhostUserMsg *vmsg)
1472 {
1473 vmsg_set_reply_u64(vmsg, dev->max_queues);
1474 return true;
1475 }
1476
1477 static bool
1478 vu_set_vring_enable_exec(VuDev *dev, VhostUserMsg *vmsg)
1479 {
1480 unsigned int index = vmsg->payload.state.index;
1481 unsigned int enable = vmsg->payload.state.num;
1482
1483 DPRINT("State.index: %u\n", index);
1484 DPRINT("State.enable: %u\n", enable);
1485
1486 if (index >= dev->max_queues) {
1487 vu_panic(dev, "Invalid vring_enable index: %u", index);
1488 return false;
1489 }
1490
1491 dev->vq[index].enable = enable;
1492 return false;
1493 }
1494
1495 static bool
1496 vu_set_slave_req_fd(VuDev *dev, VhostUserMsg *vmsg)
1497 {
1498 if (vmsg->fd_num != 1) {
1499 vu_panic(dev, "Invalid slave_req_fd message (%d fd's)", vmsg->fd_num);
1500 return false;
1501 }
1502
1503 if (dev->slave_fd != -1) {
1504 close(dev->slave_fd);
1505 }
1506 dev->slave_fd = vmsg->fds[0];
1507 DPRINT("Got slave_fd: %d\n", vmsg->fds[0]);
1508
1509 return false;
1510 }
1511
1512 static bool
1513 vu_get_config(VuDev *dev, VhostUserMsg *vmsg)
1514 {
1515 int ret = -1;
1516
1517 if (dev->iface->get_config) {
1518 ret = dev->iface->get_config(dev, vmsg->payload.config.region,
1519 vmsg->payload.config.size);
1520 }
1521
1522 if (ret) {
1523 /* resize to zero to indicate an error to master */
1524 vmsg->size = 0;
1525 }
1526
1527 return true;
1528 }
1529
1530 static bool
1531 vu_set_config(VuDev *dev, VhostUserMsg *vmsg)
1532 {
1533 int ret = -1;
1534
1535 if (dev->iface->set_config) {
1536 ret = dev->iface->set_config(dev, vmsg->payload.config.region,
1537 vmsg->payload.config.offset,
1538 vmsg->payload.config.size,
1539 vmsg->payload.config.flags);
1540 if (ret) {
1541 vu_panic(dev, "Set virtio configuration space failed");
1542 }
1543 }
1544
1545 return false;
1546 }
1547
1548 static bool
1549 vu_set_postcopy_advise(VuDev *dev, VhostUserMsg *vmsg)
1550 {
1551 dev->postcopy_ufd = -1;
1552 #ifdef UFFDIO_API
1553 struct uffdio_api api_struct;
1554
1555 dev->postcopy_ufd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK);
1556 vmsg->size = 0;
1557 #endif
1558
1559 if (dev->postcopy_ufd == -1) {
1560 vu_panic(dev, "Userfaultfd not available: %s", strerror(errno));
1561 goto out;
1562 }
1563
1564 #ifdef UFFDIO_API
1565 api_struct.api = UFFD_API;
1566 api_struct.features = 0;
1567 if (ioctl(dev->postcopy_ufd, UFFDIO_API, &api_struct)) {
1568 vu_panic(dev, "Failed UFFDIO_API: %s", strerror(errno));
1569 close(dev->postcopy_ufd);
1570 dev->postcopy_ufd = -1;
1571 goto out;
1572 }
1573 /* TODO: Stash feature flags somewhere */
1574 #endif
1575
1576 out:
1577 /* Return a ufd to the QEMU */
1578 vmsg->fd_num = 1;
1579 vmsg->fds[0] = dev->postcopy_ufd;
1580 return true; /* = send a reply */
1581 }
1582
1583 static bool
1584 vu_set_postcopy_listen(VuDev *dev, VhostUserMsg *vmsg)
1585 {
1586 if (dev->nregions) {
1587 vu_panic(dev, "Regions already registered at postcopy-listen");
1588 vmsg_set_reply_u64(vmsg, -1);
1589 return true;
1590 }
1591 dev->postcopy_listening = true;
1592
1593 vmsg_set_reply_u64(vmsg, 0);
1594 return true;
1595 }
1596
1597 static bool
1598 vu_set_postcopy_end(VuDev *dev, VhostUserMsg *vmsg)
1599 {
1600 DPRINT("%s: Entry\n", __func__);
1601 dev->postcopy_listening = false;
1602 if (dev->postcopy_ufd > 0) {
1603 close(dev->postcopy_ufd);
1604 dev->postcopy_ufd = -1;
1605 DPRINT("%s: Done close\n", __func__);
1606 }
1607
1608 vmsg_set_reply_u64(vmsg, 0);
1609 DPRINT("%s: exit\n", __func__);
1610 return true;
1611 }
1612
1613 static inline uint64_t
1614 vu_inflight_queue_size(uint16_t queue_size)
1615 {
1616 return ALIGN_UP(sizeof(VuDescStateSplit) * queue_size +
1617 sizeof(uint16_t), INFLIGHT_ALIGNMENT);
1618 }
1619
1620 #ifdef MFD_ALLOW_SEALING
1621 static void *
1622 memfd_alloc(const char *name, size_t size, unsigned int flags, int *fd)
1623 {
1624 void *ptr;
1625 int ret;
1626
1627 *fd = memfd_create(name, MFD_ALLOW_SEALING);
1628 if (*fd < 0) {
1629 return NULL;
1630 }
1631
1632 ret = ftruncate(*fd, size);
1633 if (ret < 0) {
1634 close(*fd);
1635 return NULL;
1636 }
1637
1638 ret = fcntl(*fd, F_ADD_SEALS, flags);
1639 if (ret < 0) {
1640 close(*fd);
1641 return NULL;
1642 }
1643
1644 ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, *fd, 0);
1645 if (ptr == MAP_FAILED) {
1646 close(*fd);
1647 return NULL;
1648 }
1649
1650 return ptr;
1651 }
1652 #endif
1653
1654 static bool
1655 vu_get_inflight_fd(VuDev *dev, VhostUserMsg *vmsg)
1656 {
1657 int fd = -1;
1658 void *addr = NULL;
1659 uint64_t mmap_size;
1660 uint16_t num_queues, queue_size;
1661
1662 if (vmsg->size != sizeof(vmsg->payload.inflight)) {
1663 vu_panic(dev, "Invalid get_inflight_fd message:%d", vmsg->size);
1664 vmsg->payload.inflight.mmap_size = 0;
1665 return true;
1666 }
1667
1668 num_queues = vmsg->payload.inflight.num_queues;
1669 queue_size = vmsg->payload.inflight.queue_size;
1670
1671 DPRINT("set_inflight_fd num_queues: %"PRId16"\n", num_queues);
1672 DPRINT("set_inflight_fd queue_size: %"PRId16"\n", queue_size);
1673
1674 mmap_size = vu_inflight_queue_size(queue_size) * num_queues;
1675
1676 #ifdef MFD_ALLOW_SEALING
1677 addr = memfd_alloc("vhost-inflight", mmap_size,
1678 F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL,
1679 &fd);
1680 #else
1681 vu_panic(dev, "Not implemented: memfd support is missing");
1682 #endif
1683
1684 if (!addr) {
1685 vu_panic(dev, "Failed to alloc vhost inflight area");
1686 vmsg->payload.inflight.mmap_size = 0;
1687 return true;
1688 }
1689
1690 memset(addr, 0, mmap_size);
1691
1692 dev->inflight_info.addr = addr;
1693 dev->inflight_info.size = vmsg->payload.inflight.mmap_size = mmap_size;
1694 dev->inflight_info.fd = vmsg->fds[0] = fd;
1695 vmsg->fd_num = 1;
1696 vmsg->payload.inflight.mmap_offset = 0;
1697
1698 DPRINT("send inflight mmap_size: %"PRId64"\n",
1699 vmsg->payload.inflight.mmap_size);
1700 DPRINT("send inflight mmap offset: %"PRId64"\n",
1701 vmsg->payload.inflight.mmap_offset);
1702
1703 return true;
1704 }
1705
1706 static bool
1707 vu_set_inflight_fd(VuDev *dev, VhostUserMsg *vmsg)
1708 {
1709 int fd, i;
1710 uint64_t mmap_size, mmap_offset;
1711 uint16_t num_queues, queue_size;
1712 void *rc;
1713
1714 if (vmsg->fd_num != 1 ||
1715 vmsg->size != sizeof(vmsg->payload.inflight)) {
1716 vu_panic(dev, "Invalid set_inflight_fd message size:%d fds:%d",
1717 vmsg->size, vmsg->fd_num);
1718 return false;
1719 }
1720
1721 fd = vmsg->fds[0];
1722 mmap_size = vmsg->payload.inflight.mmap_size;
1723 mmap_offset = vmsg->payload.inflight.mmap_offset;
1724 num_queues = vmsg->payload.inflight.num_queues;
1725 queue_size = vmsg->payload.inflight.queue_size;
1726
1727 DPRINT("set_inflight_fd mmap_size: %"PRId64"\n", mmap_size);
1728 DPRINT("set_inflight_fd mmap_offset: %"PRId64"\n", mmap_offset);
1729 DPRINT("set_inflight_fd num_queues: %"PRId16"\n", num_queues);
1730 DPRINT("set_inflight_fd queue_size: %"PRId16"\n", queue_size);
1731
1732 rc = mmap(0, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED,
1733 fd, mmap_offset);
1734
1735 if (rc == MAP_FAILED) {
1736 vu_panic(dev, "set_inflight_fd mmap error: %s", strerror(errno));
1737 return false;
1738 }
1739
1740 if (dev->inflight_info.fd) {
1741 close(dev->inflight_info.fd);
1742 }
1743
1744 if (dev->inflight_info.addr) {
1745 munmap(dev->inflight_info.addr, dev->inflight_info.size);
1746 }
1747
1748 dev->inflight_info.fd = fd;
1749 dev->inflight_info.addr = rc;
1750 dev->inflight_info.size = mmap_size;
1751
1752 for (i = 0; i < num_queues; i++) {
1753 dev->vq[i].inflight = (VuVirtqInflight *)rc;
1754 dev->vq[i].inflight->desc_num = queue_size;
1755 rc = (void *)((char *)rc + vu_inflight_queue_size(queue_size));
1756 }
1757
1758 return false;
1759 }
1760
1761 static bool
1762 vu_handle_vring_kick(VuDev *dev, VhostUserMsg *vmsg)
1763 {
1764 unsigned int index = vmsg->payload.state.index;
1765
1766 if (index >= dev->max_queues) {
1767 vu_panic(dev, "Invalid queue index: %u", index);
1768 return false;
1769 }
1770
1771 DPRINT("Got kick message: handler:%p idx:%u\n",
1772 dev->vq[index].handler, index);
1773
1774 if (!dev->vq[index].started) {
1775 dev->vq[index].started = true;
1776
1777 if (dev->iface->queue_set_started) {
1778 dev->iface->queue_set_started(dev, index, true);
1779 }
1780 }
1781
1782 if (dev->vq[index].handler) {
1783 dev->vq[index].handler(dev, index);
1784 }
1785
1786 return false;
1787 }
1788
1789 static bool vu_handle_get_max_memslots(VuDev *dev, VhostUserMsg *vmsg)
1790 {
1791 vmsg->flags = VHOST_USER_REPLY_MASK | VHOST_USER_VERSION;
1792 vmsg->size = sizeof(vmsg->payload.u64);
1793 vmsg->payload.u64 = VHOST_USER_MAX_RAM_SLOTS;
1794 vmsg->fd_num = 0;
1795
1796 if (!vu_message_write(dev, dev->sock, vmsg)) {
1797 vu_panic(dev, "Failed to send max ram slots: %s\n", strerror(errno));
1798 }
1799
1800 DPRINT("u64: 0x%016"PRIx64"\n", (uint64_t) VHOST_USER_MAX_RAM_SLOTS);
1801
1802 return false;
1803 }
1804
1805 static bool
1806 vu_process_message(VuDev *dev, VhostUserMsg *vmsg)
1807 {
1808 int do_reply = 0;
1809
1810 /* Print out generic part of the request. */
1811 DPRINT("================ Vhost user message ================\n");
1812 DPRINT("Request: %s (%d)\n", vu_request_to_string(vmsg->request),
1813 vmsg->request);
1814 DPRINT("Flags: 0x%x\n", vmsg->flags);
1815 DPRINT("Size: %u\n", vmsg->size);
1816
1817 if (vmsg->fd_num) {
1818 int i;
1819 DPRINT("Fds:");
1820 for (i = 0; i < vmsg->fd_num; i++) {
1821 DPRINT(" %d", vmsg->fds[i]);
1822 }
1823 DPRINT("\n");
1824 }
1825
1826 if (dev->iface->process_msg &&
1827 dev->iface->process_msg(dev, vmsg, &do_reply)) {
1828 return do_reply;
1829 }
1830
1831 switch (vmsg->request) {
1832 case VHOST_USER_GET_FEATURES:
1833 return vu_get_features_exec(dev, vmsg);
1834 case VHOST_USER_SET_FEATURES:
1835 return vu_set_features_exec(dev, vmsg);
1836 case VHOST_USER_GET_PROTOCOL_FEATURES:
1837 return vu_get_protocol_features_exec(dev, vmsg);
1838 case VHOST_USER_SET_PROTOCOL_FEATURES:
1839 return vu_set_protocol_features_exec(dev, vmsg);
1840 case VHOST_USER_SET_OWNER:
1841 return vu_set_owner_exec(dev, vmsg);
1842 case VHOST_USER_RESET_OWNER:
1843 return vu_reset_device_exec(dev, vmsg);
1844 case VHOST_USER_SET_MEM_TABLE:
1845 return vu_set_mem_table_exec(dev, vmsg);
1846 case VHOST_USER_SET_LOG_BASE:
1847 return vu_set_log_base_exec(dev, vmsg);
1848 case VHOST_USER_SET_LOG_FD:
1849 return vu_set_log_fd_exec(dev, vmsg);
1850 case VHOST_USER_SET_VRING_NUM:
1851 return vu_set_vring_num_exec(dev, vmsg);
1852 case VHOST_USER_SET_VRING_ADDR:
1853 return vu_set_vring_addr_exec(dev, vmsg);
1854 case VHOST_USER_SET_VRING_BASE:
1855 return vu_set_vring_base_exec(dev, vmsg);
1856 case VHOST_USER_GET_VRING_BASE:
1857 return vu_get_vring_base_exec(dev, vmsg);
1858 case VHOST_USER_SET_VRING_KICK:
1859 return vu_set_vring_kick_exec(dev, vmsg);
1860 case VHOST_USER_SET_VRING_CALL:
1861 return vu_set_vring_call_exec(dev, vmsg);
1862 case VHOST_USER_SET_VRING_ERR:
1863 return vu_set_vring_err_exec(dev, vmsg);
1864 case VHOST_USER_GET_QUEUE_NUM:
1865 return vu_get_queue_num_exec(dev, vmsg);
1866 case VHOST_USER_SET_VRING_ENABLE:
1867 return vu_set_vring_enable_exec(dev, vmsg);
1868 case VHOST_USER_SET_SLAVE_REQ_FD:
1869 return vu_set_slave_req_fd(dev, vmsg);
1870 case VHOST_USER_GET_CONFIG:
1871 return vu_get_config(dev, vmsg);
1872 case VHOST_USER_SET_CONFIG:
1873 return vu_set_config(dev, vmsg);
1874 case VHOST_USER_NONE:
1875 /* if you need processing before exit, override iface->process_msg */
1876 exit(0);
1877 case VHOST_USER_POSTCOPY_ADVISE:
1878 return vu_set_postcopy_advise(dev, vmsg);
1879 case VHOST_USER_POSTCOPY_LISTEN:
1880 return vu_set_postcopy_listen(dev, vmsg);
1881 case VHOST_USER_POSTCOPY_END:
1882 return vu_set_postcopy_end(dev, vmsg);
1883 case VHOST_USER_GET_INFLIGHT_FD:
1884 return vu_get_inflight_fd(dev, vmsg);
1885 case VHOST_USER_SET_INFLIGHT_FD:
1886 return vu_set_inflight_fd(dev, vmsg);
1887 case VHOST_USER_VRING_KICK:
1888 return vu_handle_vring_kick(dev, vmsg);
1889 case VHOST_USER_GET_MAX_MEM_SLOTS:
1890 return vu_handle_get_max_memslots(dev, vmsg);
1891 case VHOST_USER_ADD_MEM_REG:
1892 return vu_add_mem_reg(dev, vmsg);
1893 case VHOST_USER_REM_MEM_REG:
1894 return vu_rem_mem_reg(dev, vmsg);
1895 default:
1896 vmsg_close_fds(vmsg);
1897 vu_panic(dev, "Unhandled request: %d", vmsg->request);
1898 }
1899
1900 return false;
1901 }
1902
1903 bool
1904 vu_dispatch(VuDev *dev)
1905 {
1906 VhostUserMsg vmsg = { 0, };
1907 int reply_requested;
1908 bool need_reply, success = false;
1909
1910 if (!dev->read_msg(dev, dev->sock, &vmsg)) {
1911 goto end;
1912 }
1913
1914 need_reply = vmsg.flags & VHOST_USER_NEED_REPLY_MASK;
1915
1916 reply_requested = vu_process_message(dev, &vmsg);
1917 if (!reply_requested && need_reply) {
1918 vmsg_set_reply_u64(&vmsg, 0);
1919 reply_requested = 1;
1920 }
1921
1922 if (!reply_requested) {
1923 success = true;
1924 goto end;
1925 }
1926
1927 if (!vu_send_reply(dev, dev->sock, &vmsg)) {
1928 goto end;
1929 }
1930
1931 success = true;
1932
1933 end:
1934 free(vmsg.data);
1935 return success;
1936 }
1937
1938 void
1939 vu_deinit(VuDev *dev)
1940 {
1941 int i;
1942
1943 for (i = 0; i < dev->nregions; i++) {
1944 VuDevRegion *r = &dev->regions[i];
1945 void *m = (void *) (uintptr_t) r->mmap_addr;
1946 if (m != MAP_FAILED) {
1947 munmap(m, r->size + r->mmap_offset);
1948 }
1949 }
1950 dev->nregions = 0;
1951
1952 for (i = 0; i < dev->max_queues; i++) {
1953 VuVirtq *vq = &dev->vq[i];
1954
1955 if (vq->call_fd != -1) {
1956 close(vq->call_fd);
1957 vq->call_fd = -1;
1958 }
1959
1960 if (vq->kick_fd != -1) {
1961 dev->remove_watch(dev, vq->kick_fd);
1962 close(vq->kick_fd);
1963 vq->kick_fd = -1;
1964 }
1965
1966 if (vq->err_fd != -1) {
1967 close(vq->err_fd);
1968 vq->err_fd = -1;
1969 }
1970
1971 if (vq->resubmit_list) {
1972 free(vq->resubmit_list);
1973 vq->resubmit_list = NULL;
1974 }
1975
1976 vq->inflight = NULL;
1977 }
1978
1979 if (dev->inflight_info.addr) {
1980 munmap(dev->inflight_info.addr, dev->inflight_info.size);
1981 dev->inflight_info.addr = NULL;
1982 }
1983
1984 if (dev->inflight_info.fd > 0) {
1985 close(dev->inflight_info.fd);
1986 dev->inflight_info.fd = -1;
1987 }
1988
1989 vu_close_log(dev);
1990 if (dev->slave_fd != -1) {
1991 close(dev->slave_fd);
1992 dev->slave_fd = -1;
1993 }
1994 pthread_mutex_destroy(&dev->slave_mutex);
1995
1996 if (dev->sock != -1) {
1997 close(dev->sock);
1998 }
1999
2000 free(dev->vq);
2001 dev->vq = NULL;
2002 }
2003
2004 bool
2005 vu_init(VuDev *dev,
2006 uint16_t max_queues,
2007 int socket,
2008 vu_panic_cb panic,
2009 vu_read_msg_cb read_msg,
2010 vu_set_watch_cb set_watch,
2011 vu_remove_watch_cb remove_watch,
2012 const VuDevIface *iface)
2013 {
2014 uint16_t i;
2015
2016 assert(max_queues > 0);
2017 assert(socket >= 0);
2018 assert(set_watch);
2019 assert(remove_watch);
2020 assert(iface);
2021 assert(panic);
2022
2023 memset(dev, 0, sizeof(*dev));
2024
2025 dev->sock = socket;
2026 dev->panic = panic;
2027 dev->read_msg = read_msg ? read_msg : vu_message_read_default;
2028 dev->set_watch = set_watch;
2029 dev->remove_watch = remove_watch;
2030 dev->iface = iface;
2031 dev->log_call_fd = -1;
2032 pthread_mutex_init(&dev->slave_mutex, NULL);
2033 dev->slave_fd = -1;
2034 dev->max_queues = max_queues;
2035
2036 dev->vq = malloc(max_queues * sizeof(dev->vq[0]));
2037 if (!dev->vq) {
2038 DPRINT("%s: failed to malloc virtqueues\n", __func__);
2039 return false;
2040 }
2041
2042 for (i = 0; i < max_queues; i++) {
2043 dev->vq[i] = (VuVirtq) {
2044 .call_fd = -1, .kick_fd = -1, .err_fd = -1,
2045 .notification = true,
2046 };
2047 }
2048
2049 return true;
2050 }
2051
2052 VuVirtq *
2053 vu_get_queue(VuDev *dev, int qidx)
2054 {
2055 assert(qidx < dev->max_queues);
2056 return &dev->vq[qidx];
2057 }
2058
2059 bool
2060 vu_queue_enabled(VuDev *dev, VuVirtq *vq)
2061 {
2062 return vq->enable;
2063 }
2064
2065 bool
2066 vu_queue_started(const VuDev *dev, const VuVirtq *vq)
2067 {
2068 return vq->started;
2069 }
2070
2071 static inline uint16_t
2072 vring_avail_flags(VuVirtq *vq)
2073 {
2074 return le16toh(vq->vring.avail->flags);
2075 }
2076
2077 static inline uint16_t
2078 vring_avail_idx(VuVirtq *vq)
2079 {
2080 vq->shadow_avail_idx = le16toh(vq->vring.avail->idx);
2081
2082 return vq->shadow_avail_idx;
2083 }
2084
2085 static inline uint16_t
2086 vring_avail_ring(VuVirtq *vq, int i)
2087 {
2088 return le16toh(vq->vring.avail->ring[i]);
2089 }
2090
2091 static inline uint16_t
2092 vring_get_used_event(VuVirtq *vq)
2093 {
2094 return vring_avail_ring(vq, vq->vring.num);
2095 }
2096
2097 static int
2098 virtqueue_num_heads(VuDev *dev, VuVirtq *vq, unsigned int idx)
2099 {
2100 uint16_t num_heads = vring_avail_idx(vq) - idx;
2101
2102 /* Check it isn't doing very strange things with descriptor numbers. */
2103 if (num_heads > vq->vring.num) {
2104 vu_panic(dev, "Guest moved used index from %u to %u",
2105 idx, vq->shadow_avail_idx);
2106 return -1;
2107 }
2108 if (num_heads) {
2109 /* On success, callers read a descriptor at vq->last_avail_idx.
2110 * Make sure descriptor read does not bypass avail index read. */
2111 smp_rmb();
2112 }
2113
2114 return num_heads;
2115 }
2116
2117 static bool
2118 virtqueue_get_head(VuDev *dev, VuVirtq *vq,
2119 unsigned int idx, unsigned int *head)
2120 {
2121 /* Grab the next descriptor number they're advertising, and increment
2122 * the index we've seen. */
2123 *head = vring_avail_ring(vq, idx % vq->vring.num);
2124
2125 /* If their number is silly, that's a fatal mistake. */
2126 if (*head >= vq->vring.num) {
2127 vu_panic(dev, "Guest says index %u is available", *head);
2128 return false;
2129 }
2130
2131 return true;
2132 }
2133
2134 static int
2135 virtqueue_read_indirect_desc(VuDev *dev, struct vring_desc *desc,
2136 uint64_t addr, size_t len)
2137 {
2138 struct vring_desc *ori_desc;
2139 uint64_t read_len;
2140
2141 if (len > (VIRTQUEUE_MAX_SIZE * sizeof(struct vring_desc))) {
2142 return -1;
2143 }
2144
2145 if (len == 0) {
2146 return -1;
2147 }
2148
2149 while (len) {
2150 read_len = len;
2151 ori_desc = vu_gpa_to_va(dev, &read_len, addr);
2152 if (!ori_desc) {
2153 return -1;
2154 }
2155
2156 memcpy(desc, ori_desc, read_len);
2157 len -= read_len;
2158 addr += read_len;
2159 desc += read_len;
2160 }
2161
2162 return 0;
2163 }
2164
2165 enum {
2166 VIRTQUEUE_READ_DESC_ERROR = -1,
2167 VIRTQUEUE_READ_DESC_DONE = 0, /* end of chain */
2168 VIRTQUEUE_READ_DESC_MORE = 1, /* more buffers in chain */
2169 };
2170
2171 static int
2172 virtqueue_read_next_desc(VuDev *dev, struct vring_desc *desc,
2173 int i, unsigned int max, unsigned int *next)
2174 {
2175 /* If this descriptor says it doesn't chain, we're done. */
2176 if (!(le16toh(desc[i].flags) & VRING_DESC_F_NEXT)) {
2177 return VIRTQUEUE_READ_DESC_DONE;
2178 }
2179
2180 /* Check they're not leading us off end of descriptors. */
2181 *next = le16toh(desc[i].next);
2182 /* Make sure compiler knows to grab that: we don't want it changing! */
2183 smp_wmb();
2184
2185 if (*next >= max) {
2186 vu_panic(dev, "Desc next is %u", *next);
2187 return VIRTQUEUE_READ_DESC_ERROR;
2188 }
2189
2190 return VIRTQUEUE_READ_DESC_MORE;
2191 }
2192
2193 void
2194 vu_queue_get_avail_bytes(VuDev *dev, VuVirtq *vq, unsigned int *in_bytes,
2195 unsigned int *out_bytes,
2196 unsigned max_in_bytes, unsigned max_out_bytes)
2197 {
2198 unsigned int idx;
2199 unsigned int total_bufs, in_total, out_total;
2200 int rc;
2201
2202 idx = vq->last_avail_idx;
2203
2204 total_bufs = in_total = out_total = 0;
2205 if (unlikely(dev->broken) ||
2206 unlikely(!vq->vring.avail)) {
2207 goto done;
2208 }
2209
2210 while ((rc = virtqueue_num_heads(dev, vq, idx)) > 0) {
2211 unsigned int max, desc_len, num_bufs, indirect = 0;
2212 uint64_t desc_addr, read_len;
2213 struct vring_desc *desc;
2214 struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE];
2215 unsigned int i;
2216
2217 max = vq->vring.num;
2218 num_bufs = total_bufs;
2219 if (!virtqueue_get_head(dev, vq, idx++, &i)) {
2220 goto err;
2221 }
2222 desc = vq->vring.desc;
2223
2224 if (le16toh(desc[i].flags) & VRING_DESC_F_INDIRECT) {
2225 if (le32toh(desc[i].len) % sizeof(struct vring_desc)) {
2226 vu_panic(dev, "Invalid size for indirect buffer table");
2227 goto err;
2228 }
2229
2230 /* If we've got too many, that implies a descriptor loop. */
2231 if (num_bufs >= max) {
2232 vu_panic(dev, "Looped descriptor");
2233 goto err;
2234 }
2235
2236 /* loop over the indirect descriptor table */
2237 indirect = 1;
2238 desc_addr = le64toh(desc[i].addr);
2239 desc_len = le32toh(desc[i].len);
2240 max = desc_len / sizeof(struct vring_desc);
2241 read_len = desc_len;
2242 desc = vu_gpa_to_va(dev, &read_len, desc_addr);
2243 if (unlikely(desc && read_len != desc_len)) {
2244 /* Failed to use zero copy */
2245 desc = NULL;
2246 if (!virtqueue_read_indirect_desc(dev, desc_buf,
2247 desc_addr,
2248 desc_len)) {
2249 desc = desc_buf;
2250 }
2251 }
2252 if (!desc) {
2253 vu_panic(dev, "Invalid indirect buffer table");
2254 goto err;
2255 }
2256 num_bufs = i = 0;
2257 }
2258
2259 do {
2260 /* If we've got too many, that implies a descriptor loop. */
2261 if (++num_bufs > max) {
2262 vu_panic(dev, "Looped descriptor");
2263 goto err;
2264 }
2265
2266 if (le16toh(desc[i].flags) & VRING_DESC_F_WRITE) {
2267 in_total += le32toh(desc[i].len);
2268 } else {
2269 out_total += le32toh(desc[i].len);
2270 }
2271 if (in_total >= max_in_bytes && out_total >= max_out_bytes) {
2272 goto done;
2273 }
2274 rc = virtqueue_read_next_desc(dev, desc, i, max, &i);
2275 } while (rc == VIRTQUEUE_READ_DESC_MORE);
2276
2277 if (rc == VIRTQUEUE_READ_DESC_ERROR) {
2278 goto err;
2279 }
2280
2281 if (!indirect) {
2282 total_bufs = num_bufs;
2283 } else {
2284 total_bufs++;
2285 }
2286 }
2287 if (rc < 0) {
2288 goto err;
2289 }
2290 done:
2291 if (in_bytes) {
2292 *in_bytes = in_total;
2293 }
2294 if (out_bytes) {
2295 *out_bytes = out_total;
2296 }
2297 return;
2298
2299 err:
2300 in_total = out_total = 0;
2301 goto done;
2302 }
2303
2304 bool
2305 vu_queue_avail_bytes(VuDev *dev, VuVirtq *vq, unsigned int in_bytes,
2306 unsigned int out_bytes)
2307 {
2308 unsigned int in_total, out_total;
2309
2310 vu_queue_get_avail_bytes(dev, vq, &in_total, &out_total,
2311 in_bytes, out_bytes);
2312
2313 return in_bytes <= in_total && out_bytes <= out_total;
2314 }
2315
2316 /* Fetch avail_idx from VQ memory only when we really need to know if
2317 * guest has added some buffers. */
2318 bool
2319 vu_queue_empty(VuDev *dev, VuVirtq *vq)
2320 {
2321 if (unlikely(dev->broken) ||
2322 unlikely(!vq->vring.avail)) {
2323 return true;
2324 }
2325
2326 if (vq->shadow_avail_idx != vq->last_avail_idx) {
2327 return false;
2328 }
2329
2330 return vring_avail_idx(vq) == vq->last_avail_idx;
2331 }
2332
2333 static bool
2334 vring_notify(VuDev *dev, VuVirtq *vq)
2335 {
2336 uint16_t old, new;
2337 bool v;
2338
2339 /* We need to expose used array entries before checking used event. */
2340 smp_mb();
2341
2342 /* Always notify when queue is empty (when feature acknowledge) */
2343 if (vu_has_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY) &&
2344 !vq->inuse && vu_queue_empty(dev, vq)) {
2345 return true;
2346 }
2347
2348 if (!vu_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
2349 return !(vring_avail_flags(vq) & VRING_AVAIL_F_NO_INTERRUPT);
2350 }
2351
2352 v = vq->signalled_used_valid;
2353 vq->signalled_used_valid = true;
2354 old = vq->signalled_used;
2355 new = vq->signalled_used = vq->used_idx;
2356 return !v || vring_need_event(vring_get_used_event(vq), new, old);
2357 }
2358
2359 static void _vu_queue_notify(VuDev *dev, VuVirtq *vq, bool sync)
2360 {
2361 if (unlikely(dev->broken) ||
2362 unlikely(!vq->vring.avail)) {
2363 return;
2364 }
2365
2366 if (!vring_notify(dev, vq)) {
2367 DPRINT("skipped notify...\n");
2368 return;
2369 }
2370
2371 if (vq->call_fd < 0 &&
2372 vu_has_protocol_feature(dev,
2373 VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS) &&
2374 vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_SLAVE_REQ)) {
2375 VhostUserMsg vmsg = {
2376 .request = VHOST_USER_SLAVE_VRING_CALL,
2377 .flags = VHOST_USER_VERSION,
2378 .size = sizeof(vmsg.payload.state),
2379 .payload.state = {
2380 .index = vq - dev->vq,
2381 },
2382 };
2383 bool ack = sync &&
2384 vu_has_protocol_feature(dev,
2385 VHOST_USER_PROTOCOL_F_REPLY_ACK);
2386
2387 if (ack) {
2388 vmsg.flags |= VHOST_USER_NEED_REPLY_MASK;
2389 }
2390
2391 vu_message_write(dev, dev->slave_fd, &vmsg);
2392 if (ack) {
2393 vu_message_read_default(dev, dev->slave_fd, &vmsg);
2394 }
2395 return;
2396 }
2397
2398 if (eventfd_write(vq->call_fd, 1) < 0) {
2399 vu_panic(dev, "Error writing eventfd: %s", strerror(errno));
2400 }
2401 }
2402
2403 void vu_queue_notify(VuDev *dev, VuVirtq *vq)
2404 {
2405 _vu_queue_notify(dev, vq, false);
2406 }
2407
2408 void vu_queue_notify_sync(VuDev *dev, VuVirtq *vq)
2409 {
2410 _vu_queue_notify(dev, vq, true);
2411 }
2412
2413 static inline void
2414 vring_used_flags_set_bit(VuVirtq *vq, int mask)
2415 {
2416 uint16_t *flags;
2417
2418 flags = (uint16_t *)((char*)vq->vring.used +
2419 offsetof(struct vring_used, flags));
2420 *flags = htole16(le16toh(*flags) | mask);
2421 }
2422
2423 static inline void
2424 vring_used_flags_unset_bit(VuVirtq *vq, int mask)
2425 {
2426 uint16_t *flags;
2427
2428 flags = (uint16_t *)((char*)vq->vring.used +
2429 offsetof(struct vring_used, flags));
2430 *flags = htole16(le16toh(*flags) & ~mask);
2431 }
2432
2433 static inline void
2434 vring_set_avail_event(VuVirtq *vq, uint16_t val)
2435 {
2436 uint16_t *avail;
2437
2438 if (!vq->notification) {
2439 return;
2440 }
2441
2442 avail = (uint16_t *)&vq->vring.used->ring[vq->vring.num];
2443 *avail = htole16(val);
2444 }
2445
2446 void
2447 vu_queue_set_notification(VuDev *dev, VuVirtq *vq, int enable)
2448 {
2449 vq->notification = enable;
2450 if (vu_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
2451 vring_set_avail_event(vq, vring_avail_idx(vq));
2452 } else if (enable) {
2453 vring_used_flags_unset_bit(vq, VRING_USED_F_NO_NOTIFY);
2454 } else {
2455 vring_used_flags_set_bit(vq, VRING_USED_F_NO_NOTIFY);
2456 }
2457 if (enable) {
2458 /* Expose avail event/used flags before caller checks the avail idx. */
2459 smp_mb();
2460 }
2461 }
2462
2463 static bool
2464 virtqueue_map_desc(VuDev *dev,
2465 unsigned int *p_num_sg, struct iovec *iov,
2466 unsigned int max_num_sg, bool is_write,
2467 uint64_t pa, size_t sz)
2468 {
2469 unsigned num_sg = *p_num_sg;
2470
2471 assert(num_sg <= max_num_sg);
2472
2473 if (!sz) {
2474 vu_panic(dev, "virtio: zero sized buffers are not allowed");
2475 return false;
2476 }
2477
2478 while (sz) {
2479 uint64_t len = sz;
2480
2481 if (num_sg == max_num_sg) {
2482 vu_panic(dev, "virtio: too many descriptors in indirect table");
2483 return false;
2484 }
2485
2486 iov[num_sg].iov_base = vu_gpa_to_va(dev, &len, pa);
2487 if (iov[num_sg].iov_base == NULL) {
2488 vu_panic(dev, "virtio: invalid address for buffers");
2489 return false;
2490 }
2491 iov[num_sg].iov_len = len;
2492 num_sg++;
2493 sz -= len;
2494 pa += len;
2495 }
2496
2497 *p_num_sg = num_sg;
2498 return true;
2499 }
2500
2501 static void *
2502 virtqueue_alloc_element(size_t sz,
2503 unsigned out_num, unsigned in_num)
2504 {
2505 VuVirtqElement *elem;
2506 size_t in_sg_ofs = ALIGN_UP(sz, __alignof__(elem->in_sg[0]));
2507 size_t out_sg_ofs = in_sg_ofs + in_num * sizeof(elem->in_sg[0]);
2508 size_t out_sg_end = out_sg_ofs + out_num * sizeof(elem->out_sg[0]);
2509
2510 assert(sz >= sizeof(VuVirtqElement));
2511 elem = malloc(out_sg_end);
2512 elem->out_num = out_num;
2513 elem->in_num = in_num;
2514 elem->in_sg = (void *)elem + in_sg_ofs;
2515 elem->out_sg = (void *)elem + out_sg_ofs;
2516 return elem;
2517 }
2518
2519 static void *
2520 vu_queue_map_desc(VuDev *dev, VuVirtq *vq, unsigned int idx, size_t sz)
2521 {
2522 struct vring_desc *desc = vq->vring.desc;
2523 uint64_t desc_addr, read_len;
2524 unsigned int desc_len;
2525 unsigned int max = vq->vring.num;
2526 unsigned int i = idx;
2527 VuVirtqElement *elem;
2528 unsigned int out_num = 0, in_num = 0;
2529 struct iovec iov[VIRTQUEUE_MAX_SIZE];
2530 struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE];
2531 int rc;
2532
2533 if (le16toh(desc[i].flags) & VRING_DESC_F_INDIRECT) {
2534 if (le32toh(desc[i].len) % sizeof(struct vring_desc)) {
2535 vu_panic(dev, "Invalid size for indirect buffer table");
2536 return NULL;
2537 }
2538
2539 /* loop over the indirect descriptor table */
2540 desc_addr = le64toh(desc[i].addr);
2541 desc_len = le32toh(desc[i].len);
2542 max = desc_len / sizeof(struct vring_desc);
2543 read_len = desc_len;
2544 desc = vu_gpa_to_va(dev, &read_len, desc_addr);
2545 if (unlikely(desc && read_len != desc_len)) {
2546 /* Failed to use zero copy */
2547 desc = NULL;
2548 if (!virtqueue_read_indirect_desc(dev, desc_buf,
2549 desc_addr,
2550 desc_len)) {
2551 desc = desc_buf;
2552 }
2553 }
2554 if (!desc) {
2555 vu_panic(dev, "Invalid indirect buffer table");
2556 return NULL;
2557 }
2558 i = 0;
2559 }
2560
2561 /* Collect all the descriptors */
2562 do {
2563 if (le16toh(desc[i].flags) & VRING_DESC_F_WRITE) {
2564 if (!virtqueue_map_desc(dev, &in_num, iov + out_num,
2565 VIRTQUEUE_MAX_SIZE - out_num, true,
2566 le64toh(desc[i].addr),
2567 le32toh(desc[i].len))) {
2568 return NULL;
2569 }
2570 } else {
2571 if (in_num) {
2572 vu_panic(dev, "Incorrect order for descriptors");
2573 return NULL;
2574 }
2575 if (!virtqueue_map_desc(dev, &out_num, iov,
2576 VIRTQUEUE_MAX_SIZE, false,
2577 le64toh(desc[i].addr),
2578 le32toh(desc[i].len))) {
2579 return NULL;
2580 }
2581 }
2582
2583 /* If we've got too many, that implies a descriptor loop. */
2584 if ((in_num + out_num) > max) {
2585 vu_panic(dev, "Looped descriptor");
2586 return NULL;
2587 }
2588 rc = virtqueue_read_next_desc(dev, desc, i, max, &i);
2589 } while (rc == VIRTQUEUE_READ_DESC_MORE);
2590
2591 if (rc == VIRTQUEUE_READ_DESC_ERROR) {
2592 vu_panic(dev, "read descriptor error");
2593 return NULL;
2594 }
2595
2596 /* Now copy what we have collected and mapped */
2597 elem = virtqueue_alloc_element(sz, out_num, in_num);
2598 elem->index = idx;
2599 for (i = 0; i < out_num; i++) {
2600 elem->out_sg[i] = iov[i];
2601 }
2602 for (i = 0; i < in_num; i++) {
2603 elem->in_sg[i] = iov[out_num + i];
2604 }
2605
2606 return elem;
2607 }
2608
2609 static int
2610 vu_queue_inflight_get(VuDev *dev, VuVirtq *vq, int desc_idx)
2611 {
2612 if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
2613 return 0;
2614 }
2615
2616 if (unlikely(!vq->inflight)) {
2617 return -1;
2618 }
2619
2620 vq->inflight->desc[desc_idx].counter = vq->counter++;
2621 vq->inflight->desc[desc_idx].inflight = 1;
2622
2623 return 0;
2624 }
2625
2626 static int
2627 vu_queue_inflight_pre_put(VuDev *dev, VuVirtq *vq, int desc_idx)
2628 {
2629 if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
2630 return 0;
2631 }
2632
2633 if (unlikely(!vq->inflight)) {
2634 return -1;
2635 }
2636
2637 vq->inflight->last_batch_head = desc_idx;
2638
2639 return 0;
2640 }
2641
2642 static int
2643 vu_queue_inflight_post_put(VuDev *dev, VuVirtq *vq, int desc_idx)
2644 {
2645 if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
2646 return 0;
2647 }
2648
2649 if (unlikely(!vq->inflight)) {
2650 return -1;
2651 }
2652
2653 barrier();
2654
2655 vq->inflight->desc[desc_idx].inflight = 0;
2656
2657 barrier();
2658
2659 vq->inflight->used_idx = vq->used_idx;
2660
2661 return 0;
2662 }
2663
2664 void *
2665 vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz)
2666 {
2667 int i;
2668 unsigned int head;
2669 VuVirtqElement *elem;
2670
2671 if (unlikely(dev->broken) ||
2672 unlikely(!vq->vring.avail)) {
2673 return NULL;
2674 }
2675
2676 if (unlikely(vq->resubmit_list && vq->resubmit_num > 0)) {
2677 i = (--vq->resubmit_num);
2678 elem = vu_queue_map_desc(dev, vq, vq->resubmit_list[i].index, sz);
2679
2680 if (!vq->resubmit_num) {
2681 free(vq->resubmit_list);
2682 vq->resubmit_list = NULL;
2683 }
2684
2685 return elem;
2686 }
2687
2688 if (vu_queue_empty(dev, vq)) {
2689 return NULL;
2690 }
2691 /*
2692 * Needed after virtio_queue_empty(), see comment in
2693 * virtqueue_num_heads().
2694 */
2695 smp_rmb();
2696
2697 if (vq->inuse >= vq->vring.num) {
2698 vu_panic(dev, "Virtqueue size exceeded");
2699 return NULL;
2700 }
2701
2702 if (!virtqueue_get_head(dev, vq, vq->last_avail_idx++, &head)) {
2703 return NULL;
2704 }
2705
2706 if (vu_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
2707 vring_set_avail_event(vq, vq->last_avail_idx);
2708 }
2709
2710 elem = vu_queue_map_desc(dev, vq, head, sz);
2711
2712 if (!elem) {
2713 return NULL;
2714 }
2715
2716 vq->inuse++;
2717
2718 vu_queue_inflight_get(dev, vq, head);
2719
2720 return elem;
2721 }
2722
2723 static void
2724 vu_queue_detach_element(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem,
2725 size_t len)
2726 {
2727 vq->inuse--;
2728 /* unmap, when DMA support is added */
2729 }
2730
2731 void
2732 vu_queue_unpop(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem,
2733 size_t len)
2734 {
2735 vq->last_avail_idx--;
2736 vu_queue_detach_element(dev, vq, elem, len);
2737 }
2738
2739 bool
2740 vu_queue_rewind(VuDev *dev, VuVirtq *vq, unsigned int num)
2741 {
2742 if (num > vq->inuse) {
2743 return false;
2744 }
2745 vq->last_avail_idx -= num;
2746 vq->inuse -= num;
2747 return true;
2748 }
2749
2750 static inline
2751 void vring_used_write(VuDev *dev, VuVirtq *vq,
2752 struct vring_used_elem *uelem, int i)
2753 {
2754 struct vring_used *used = vq->vring.used;
2755
2756 used->ring[i] = *uelem;
2757 vu_log_write(dev, vq->vring.log_guest_addr +
2758 offsetof(struct vring_used, ring[i]),
2759 sizeof(used->ring[i]));
2760 }
2761
2762
2763 static void
2764 vu_log_queue_fill(VuDev *dev, VuVirtq *vq,
2765 const VuVirtqElement *elem,
2766 unsigned int len)
2767 {
2768 struct vring_desc *desc = vq->vring.desc;
2769 unsigned int i, max, min, desc_len;
2770 uint64_t desc_addr, read_len;
2771 struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE];
2772 unsigned num_bufs = 0;
2773
2774 max = vq->vring.num;
2775 i = elem->index;
2776
2777 if (le16toh(desc[i].flags) & VRING_DESC_F_INDIRECT) {
2778 if (le32toh(desc[i].len) % sizeof(struct vring_desc)) {
2779 vu_panic(dev, "Invalid size for indirect buffer table");
2780 return;
2781 }
2782
2783 /* loop over the indirect descriptor table */
2784 desc_addr = le64toh(desc[i].addr);
2785 desc_len = le32toh(desc[i].len);
2786 max = desc_len / sizeof(struct vring_desc);
2787 read_len = desc_len;
2788 desc = vu_gpa_to_va(dev, &read_len, desc_addr);
2789 if (unlikely(desc && read_len != desc_len)) {
2790 /* Failed to use zero copy */
2791 desc = NULL;
2792 if (!virtqueue_read_indirect_desc(dev, desc_buf,
2793 desc_addr,
2794 desc_len)) {
2795 desc = desc_buf;
2796 }
2797 }
2798 if (!desc) {
2799 vu_panic(dev, "Invalid indirect buffer table");
2800 return;
2801 }
2802 i = 0;
2803 }
2804
2805 do {
2806 if (++num_bufs > max) {
2807 vu_panic(dev, "Looped descriptor");
2808 return;
2809 }
2810
2811 if (le16toh(desc[i].flags) & VRING_DESC_F_WRITE) {
2812 min = MIN(le32toh(desc[i].len), len);
2813 vu_log_write(dev, le64toh(desc[i].addr), min);
2814 len -= min;
2815 }
2816
2817 } while (len > 0 &&
2818 (virtqueue_read_next_desc(dev, desc, i, max, &i)
2819 == VIRTQUEUE_READ_DESC_MORE));
2820 }
2821
2822 void
2823 vu_queue_fill(VuDev *dev, VuVirtq *vq,
2824 const VuVirtqElement *elem,
2825 unsigned int len, unsigned int idx)
2826 {
2827 struct vring_used_elem uelem;
2828
2829 if (unlikely(dev->broken) ||
2830 unlikely(!vq->vring.avail)) {
2831 return;
2832 }
2833
2834 vu_log_queue_fill(dev, vq, elem, len);
2835
2836 idx = (idx + vq->used_idx) % vq->vring.num;
2837
2838 uelem.id = htole32(elem->index);
2839 uelem.len = htole32(len);
2840 vring_used_write(dev, vq, &uelem, idx);
2841 }
2842
2843 static inline
2844 void vring_used_idx_set(VuDev *dev, VuVirtq *vq, uint16_t val)
2845 {
2846 vq->vring.used->idx = htole16(val);
2847 vu_log_write(dev,
2848 vq->vring.log_guest_addr + offsetof(struct vring_used, idx),
2849 sizeof(vq->vring.used->idx));
2850
2851 vq->used_idx = val;
2852 }
2853
2854 void
2855 vu_queue_flush(VuDev *dev, VuVirtq *vq, unsigned int count)
2856 {
2857 uint16_t old, new;
2858
2859 if (unlikely(dev->broken) ||
2860 unlikely(!vq->vring.avail)) {
2861 return;
2862 }
2863
2864 /* Make sure buffer is written before we update index. */
2865 smp_wmb();
2866
2867 old = vq->used_idx;
2868 new = old + count;
2869 vring_used_idx_set(dev, vq, new);
2870 vq->inuse -= count;
2871 if (unlikely((int16_t)(new - vq->signalled_used) < (uint16_t)(new - old))) {
2872 vq->signalled_used_valid = false;
2873 }
2874 }
2875
2876 void
2877 vu_queue_push(VuDev *dev, VuVirtq *vq,
2878 const VuVirtqElement *elem, unsigned int len)
2879 {
2880 vu_queue_fill(dev, vq, elem, len, 0);
2881 vu_queue_inflight_pre_put(dev, vq, elem->index);
2882 vu_queue_flush(dev, vq, 1);
2883 vu_queue_inflight_post_put(dev, vq, elem->index);
2884 }
QEmu