Merge tag 'edgar/xilinx-next-2022-09-21.for-upstream' of https://github.com/edgarigl...
[qemu.git] / hw / virtio / vhost.c
1 /*
2 * vhost support
3 *
4 * Copyright Red Hat, Inc. 2010
5 *
6 * Authors:
7 * Michael S. Tsirkin <mst@redhat.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
11 *
12 * Contributions after 2012-01-13 are licensed under the terms of the
13 * GNU GPL, version 2 or (at your option) any later version.
14 */
15
16 #include "qemu/osdep.h"
17 #include "qapi/error.h"
18 #include "hw/virtio/vhost.h"
19 #include "qemu/atomic.h"
20 #include "qemu/range.h"
21 #include "qemu/error-report.h"
22 #include "qemu/memfd.h"
23 #include "standard-headers/linux/vhost_types.h"
24 #include "hw/virtio/virtio-bus.h"
25 #include "hw/virtio/virtio-access.h"
26 #include "migration/blocker.h"
27 #include "migration/qemu-file-types.h"
28 #include "sysemu/dma.h"
29 #include "sysemu/tcg.h"
30 #include "trace.h"
31
32 /* enabled until disconnected backend stabilizes */
33 #define _VHOST_DEBUG 1
34
35 #ifdef _VHOST_DEBUG
36 #define VHOST_OPS_DEBUG(retval, fmt, ...) \
37 do { \
38 error_report(fmt ": %s (%d)", ## __VA_ARGS__, \
39 strerror(-retval), -retval); \
40 } while (0)
41 #else
42 #define VHOST_OPS_DEBUG(retval, fmt, ...) \
43 do { } while (0)
44 #endif
45
46 static struct vhost_log *vhost_log;
47 static struct vhost_log *vhost_log_shm;
48
49 static unsigned int used_memslots;
50 static QLIST_HEAD(, vhost_dev) vhost_devices =
51 QLIST_HEAD_INITIALIZER(vhost_devices);
52
53 bool vhost_has_free_slot(void)
54 {
55 unsigned int slots_limit = ~0U;
56 struct vhost_dev *hdev;
57
58 QLIST_FOREACH(hdev, &vhost_devices, entry) {
59 unsigned int r = hdev->vhost_ops->vhost_backend_memslots_limit(hdev);
60 slots_limit = MIN(slots_limit, r);
61 }
62 return slots_limit > used_memslots;
63 }
64
65 static void vhost_dev_sync_region(struct vhost_dev *dev,
66 MemoryRegionSection *section,
67 uint64_t mfirst, uint64_t mlast,
68 uint64_t rfirst, uint64_t rlast)
69 {
70 vhost_log_chunk_t *log = dev->log->log;
71
72 uint64_t start = MAX(mfirst, rfirst);
73 uint64_t end = MIN(mlast, rlast);
74 vhost_log_chunk_t *from = log + start / VHOST_LOG_CHUNK;
75 vhost_log_chunk_t *to = log + end / VHOST_LOG_CHUNK + 1;
76 uint64_t addr = QEMU_ALIGN_DOWN(start, VHOST_LOG_CHUNK);
77
78 if (end < start) {
79 return;
80 }
81 assert(end / VHOST_LOG_CHUNK < dev->log_size);
82 assert(start / VHOST_LOG_CHUNK < dev->log_size);
83
84 for (;from < to; ++from) {
85 vhost_log_chunk_t log;
86 /* We first check with non-atomic: much cheaper,
87 * and we expect non-dirty to be the common case. */
88 if (!*from) {
89 addr += VHOST_LOG_CHUNK;
90 continue;
91 }
92 /* Data must be read atomically. We don't really need barrier semantics
93 * but it's easier to use atomic_* than roll our own. */
94 log = qatomic_xchg(from, 0);
95 while (log) {
96 int bit = ctzl(log);
97 hwaddr page_addr;
98 hwaddr section_offset;
99 hwaddr mr_offset;
100 page_addr = addr + bit * VHOST_LOG_PAGE;
101 section_offset = page_addr - section->offset_within_address_space;
102 mr_offset = section_offset + section->offset_within_region;
103 memory_region_set_dirty(section->mr, mr_offset, VHOST_LOG_PAGE);
104 log &= ~(0x1ull << bit);
105 }
106 addr += VHOST_LOG_CHUNK;
107 }
108 }
109
110 static int vhost_sync_dirty_bitmap(struct vhost_dev *dev,
111 MemoryRegionSection *section,
112 hwaddr first,
113 hwaddr last)
114 {
115 int i;
116 hwaddr start_addr;
117 hwaddr end_addr;
118
119 if (!dev->log_enabled || !dev->started) {
120 return 0;
121 }
122 start_addr = section->offset_within_address_space;
123 end_addr = range_get_last(start_addr, int128_get64(section->size));
124 start_addr = MAX(first, start_addr);
125 end_addr = MIN(last, end_addr);
126
127 for (i = 0; i < dev->mem->nregions; ++i) {
128 struct vhost_memory_region *reg = dev->mem->regions + i;
129 vhost_dev_sync_region(dev, section, start_addr, end_addr,
130 reg->guest_phys_addr,
131 range_get_last(reg->guest_phys_addr,
132 reg->memory_size));
133 }
134 for (i = 0; i < dev->nvqs; ++i) {
135 struct vhost_virtqueue *vq = dev->vqs + i;
136
137 if (!vq->used_phys && !vq->used_size) {
138 continue;
139 }
140
141 vhost_dev_sync_region(dev, section, start_addr, end_addr, vq->used_phys,
142 range_get_last(vq->used_phys, vq->used_size));
143 }
144 return 0;
145 }
146
147 static void vhost_log_sync(MemoryListener *listener,
148 MemoryRegionSection *section)
149 {
150 struct vhost_dev *dev = container_of(listener, struct vhost_dev,
151 memory_listener);
152 vhost_sync_dirty_bitmap(dev, section, 0x0, ~0x0ULL);
153 }
154
155 static void vhost_log_sync_range(struct vhost_dev *dev,
156 hwaddr first, hwaddr last)
157 {
158 int i;
159 /* FIXME: this is N^2 in number of sections */
160 for (i = 0; i < dev->n_mem_sections; ++i) {
161 MemoryRegionSection *section = &dev->mem_sections[i];
162 vhost_sync_dirty_bitmap(dev, section, first, last);
163 }
164 }
165
166 static uint64_t vhost_get_log_size(struct vhost_dev *dev)
167 {
168 uint64_t log_size = 0;
169 int i;
170 for (i = 0; i < dev->mem->nregions; ++i) {
171 struct vhost_memory_region *reg = dev->mem->regions + i;
172 uint64_t last = range_get_last(reg->guest_phys_addr,
173 reg->memory_size);
174 log_size = MAX(log_size, last / VHOST_LOG_CHUNK + 1);
175 }
176 return log_size;
177 }
178
179 static int vhost_set_backend_type(struct vhost_dev *dev,
180 VhostBackendType backend_type)
181 {
182 int r = 0;
183
184 switch (backend_type) {
185 #ifdef CONFIG_VHOST_KERNEL
186 case VHOST_BACKEND_TYPE_KERNEL:
187 dev->vhost_ops = &kernel_ops;
188 break;
189 #endif
190 #ifdef CONFIG_VHOST_USER
191 case VHOST_BACKEND_TYPE_USER:
192 dev->vhost_ops = &user_ops;
193 break;
194 #endif
195 #ifdef CONFIG_VHOST_VDPA
196 case VHOST_BACKEND_TYPE_VDPA:
197 dev->vhost_ops = &vdpa_ops;
198 break;
199 #endif
200 default:
201 error_report("Unknown vhost backend type");
202 r = -1;
203 }
204
205 return r;
206 }
207
208 static struct vhost_log *vhost_log_alloc(uint64_t size, bool share)
209 {
210 Error *err = NULL;
211 struct vhost_log *log;
212 uint64_t logsize = size * sizeof(*(log->log));
213 int fd = -1;
214
215 log = g_new0(struct vhost_log, 1);
216 if (share) {
217 log->log = qemu_memfd_alloc("vhost-log", logsize,
218 F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL,
219 &fd, &err);
220 if (err) {
221 error_report_err(err);
222 g_free(log);
223 return NULL;
224 }
225 memset(log->log, 0, logsize);
226 } else {
227 log->log = g_malloc0(logsize);
228 }
229
230 log->size = size;
231 log->refcnt = 1;
232 log->fd = fd;
233
234 return log;
235 }
236
237 static struct vhost_log *vhost_log_get(uint64_t size, bool share)
238 {
239 struct vhost_log *log = share ? vhost_log_shm : vhost_log;
240
241 if (!log || log->size != size) {
242 log = vhost_log_alloc(size, share);
243 if (share) {
244 vhost_log_shm = log;
245 } else {
246 vhost_log = log;
247 }
248 } else {
249 ++log->refcnt;
250 }
251
252 return log;
253 }
254
255 static void vhost_log_put(struct vhost_dev *dev, bool sync)
256 {
257 struct vhost_log *log = dev->log;
258
259 if (!log) {
260 return;
261 }
262
263 --log->refcnt;
264 if (log->refcnt == 0) {
265 /* Sync only the range covered by the old log */
266 if (dev->log_size && sync) {
267 vhost_log_sync_range(dev, 0, dev->log_size * VHOST_LOG_CHUNK - 1);
268 }
269
270 if (vhost_log == log) {
271 g_free(log->log);
272 vhost_log = NULL;
273 } else if (vhost_log_shm == log) {
274 qemu_memfd_free(log->log, log->size * sizeof(*(log->log)),
275 log->fd);
276 vhost_log_shm = NULL;
277 }
278
279 g_free(log);
280 }
281
282 dev->log = NULL;
283 dev->log_size = 0;
284 }
285
286 static bool vhost_dev_log_is_shared(struct vhost_dev *dev)
287 {
288 return dev->vhost_ops->vhost_requires_shm_log &&
289 dev->vhost_ops->vhost_requires_shm_log(dev);
290 }
291
292 static inline void vhost_dev_log_resize(struct vhost_dev *dev, uint64_t size)
293 {
294 struct vhost_log *log = vhost_log_get(size, vhost_dev_log_is_shared(dev));
295 uint64_t log_base = (uintptr_t)log->log;
296 int r;
297
298 /* inform backend of log switching, this must be done before
299 releasing the current log, to ensure no logging is lost */
300 r = dev->vhost_ops->vhost_set_log_base(dev, log_base, log);
301 if (r < 0) {
302 VHOST_OPS_DEBUG(r, "vhost_set_log_base failed");
303 }
304
305 vhost_log_put(dev, true);
306 dev->log = log;
307 dev->log_size = size;
308 }
309
310 static int vhost_dev_has_iommu(struct vhost_dev *dev)
311 {
312 VirtIODevice *vdev = dev->vdev;
313
314 /*
315 * For vhost, VIRTIO_F_IOMMU_PLATFORM means the backend support
316 * incremental memory mapping API via IOTLB API. For platform that
317 * does not have IOMMU, there's no need to enable this feature
318 * which may cause unnecessary IOTLB miss/update transactions.
319 */
320 return virtio_bus_device_iommu_enabled(vdev) &&
321 virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM);
322 }
323
324 static void *vhost_memory_map(struct vhost_dev *dev, hwaddr addr,
325 hwaddr *plen, bool is_write)
326 {
327 if (!vhost_dev_has_iommu(dev)) {
328 return cpu_physical_memory_map(addr, plen, is_write);
329 } else {
330 return (void *)(uintptr_t)addr;
331 }
332 }
333
334 static void vhost_memory_unmap(struct vhost_dev *dev, void *buffer,
335 hwaddr len, int is_write,
336 hwaddr access_len)
337 {
338 if (!vhost_dev_has_iommu(dev)) {
339 cpu_physical_memory_unmap(buffer, len, is_write, access_len);
340 }
341 }
342
343 static int vhost_verify_ring_part_mapping(void *ring_hva,
344 uint64_t ring_gpa,
345 uint64_t ring_size,
346 void *reg_hva,
347 uint64_t reg_gpa,
348 uint64_t reg_size)
349 {
350 uint64_t hva_ring_offset;
351 uint64_t ring_last = range_get_last(ring_gpa, ring_size);
352 uint64_t reg_last = range_get_last(reg_gpa, reg_size);
353
354 if (ring_last < reg_gpa || ring_gpa > reg_last) {
355 return 0;
356 }
357 /* check that whole ring's is mapped */
358 if (ring_last > reg_last) {
359 return -ENOMEM;
360 }
361 /* check that ring's MemoryRegion wasn't replaced */
362 hva_ring_offset = ring_gpa - reg_gpa;
363 if (ring_hva != reg_hva + hva_ring_offset) {
364 return -EBUSY;
365 }
366
367 return 0;
368 }
369
370 static int vhost_verify_ring_mappings(struct vhost_dev *dev,
371 void *reg_hva,
372 uint64_t reg_gpa,
373 uint64_t reg_size)
374 {
375 int i, j;
376 int r = 0;
377 const char *part_name[] = {
378 "descriptor table",
379 "available ring",
380 "used ring"
381 };
382
383 if (vhost_dev_has_iommu(dev)) {
384 return 0;
385 }
386
387 for (i = 0; i < dev->nvqs; ++i) {
388 struct vhost_virtqueue *vq = dev->vqs + i;
389
390 if (vq->desc_phys == 0) {
391 continue;
392 }
393
394 j = 0;
395 r = vhost_verify_ring_part_mapping(
396 vq->desc, vq->desc_phys, vq->desc_size,
397 reg_hva, reg_gpa, reg_size);
398 if (r) {
399 break;
400 }
401
402 j++;
403 r = vhost_verify_ring_part_mapping(
404 vq->avail, vq->avail_phys, vq->avail_size,
405 reg_hva, reg_gpa, reg_size);
406 if (r) {
407 break;
408 }
409
410 j++;
411 r = vhost_verify_ring_part_mapping(
412 vq->used, vq->used_phys, vq->used_size,
413 reg_hva, reg_gpa, reg_size);
414 if (r) {
415 break;
416 }
417 }
418
419 if (r == -ENOMEM) {
420 error_report("Unable to map %s for ring %d", part_name[j], i);
421 } else if (r == -EBUSY) {
422 error_report("%s relocated for ring %d", part_name[j], i);
423 }
424 return r;
425 }
426
427 /*
428 * vhost_section: identify sections needed for vhost access
429 *
430 * We only care about RAM sections here (where virtqueue and guest
431 * internals accessed by virtio might live). If we find one we still
432 * allow the backend to potentially filter it out of our list.
433 */
434 static bool vhost_section(struct vhost_dev *dev, MemoryRegionSection *section)
435 {
436 MemoryRegion *mr = section->mr;
437
438 if (memory_region_is_ram(mr) && !memory_region_is_rom(mr)) {
439 uint8_t dirty_mask = memory_region_get_dirty_log_mask(mr);
440 uint8_t handled_dirty;
441
442 /*
443 * Kernel based vhost doesn't handle any block which is doing
444 * dirty-tracking other than migration for which it has
445 * specific logging support. However for TCG the kernel never
446 * gets involved anyway so we can also ignore it's
447 * self-modiying code detection flags. However a vhost-user
448 * client could still confuse a TCG guest if it re-writes
449 * executable memory that has already been translated.
450 */
451 handled_dirty = (1 << DIRTY_MEMORY_MIGRATION) |
452 (1 << DIRTY_MEMORY_CODE);
453
454 if (dirty_mask & ~handled_dirty) {
455 trace_vhost_reject_section(mr->name, 1);
456 return false;
457 }
458
459 if (dev->vhost_ops->vhost_backend_mem_section_filter &&
460 !dev->vhost_ops->vhost_backend_mem_section_filter(dev, section)) {
461 trace_vhost_reject_section(mr->name, 2);
462 return false;
463 }
464
465 trace_vhost_section(mr->name);
466 return true;
467 } else {
468 trace_vhost_reject_section(mr->name, 3);
469 return false;
470 }
471 }
472
473 static void vhost_begin(MemoryListener *listener)
474 {
475 struct vhost_dev *dev = container_of(listener, struct vhost_dev,
476 memory_listener);
477 dev->tmp_sections = NULL;
478 dev->n_tmp_sections = 0;
479 }
480
481 static void vhost_commit(MemoryListener *listener)
482 {
483 struct vhost_dev *dev = container_of(listener, struct vhost_dev,
484 memory_listener);
485 MemoryRegionSection *old_sections;
486 int n_old_sections;
487 uint64_t log_size;
488 size_t regions_size;
489 int r;
490 int i;
491 bool changed = false;
492
493 /* Note we can be called before the device is started, but then
494 * starting the device calls set_mem_table, so we need to have
495 * built the data structures.
496 */
497 old_sections = dev->mem_sections;
498 n_old_sections = dev->n_mem_sections;
499 dev->mem_sections = dev->tmp_sections;
500 dev->n_mem_sections = dev->n_tmp_sections;
501
502 if (dev->n_mem_sections != n_old_sections) {
503 changed = true;
504 } else {
505 /* Same size, lets check the contents */
506 for (int i = 0; i < n_old_sections; i++) {
507 if (!MemoryRegionSection_eq(&old_sections[i],
508 &dev->mem_sections[i])) {
509 changed = true;
510 break;
511 }
512 }
513 }
514
515 trace_vhost_commit(dev->started, changed);
516 if (!changed) {
517 goto out;
518 }
519
520 /* Rebuild the regions list from the new sections list */
521 regions_size = offsetof(struct vhost_memory, regions) +
522 dev->n_mem_sections * sizeof dev->mem->regions[0];
523 dev->mem = g_realloc(dev->mem, regions_size);
524 dev->mem->nregions = dev->n_mem_sections;
525 used_memslots = dev->mem->nregions;
526 for (i = 0; i < dev->n_mem_sections; i++) {
527 struct vhost_memory_region *cur_vmr = dev->mem->regions + i;
528 struct MemoryRegionSection *mrs = dev->mem_sections + i;
529
530 cur_vmr->guest_phys_addr = mrs->offset_within_address_space;
531 cur_vmr->memory_size = int128_get64(mrs->size);
532 cur_vmr->userspace_addr =
533 (uintptr_t)memory_region_get_ram_ptr(mrs->mr) +
534 mrs->offset_within_region;
535 cur_vmr->flags_padding = 0;
536 }
537
538 if (!dev->started) {
539 goto out;
540 }
541
542 for (i = 0; i < dev->mem->nregions; i++) {
543 if (vhost_verify_ring_mappings(dev,
544 (void *)(uintptr_t)dev->mem->regions[i].userspace_addr,
545 dev->mem->regions[i].guest_phys_addr,
546 dev->mem->regions[i].memory_size)) {
547 error_report("Verify ring failure on region %d", i);
548 abort();
549 }
550 }
551
552 if (!dev->log_enabled) {
553 r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem);
554 if (r < 0) {
555 VHOST_OPS_DEBUG(r, "vhost_set_mem_table failed");
556 }
557 goto out;
558 }
559 log_size = vhost_get_log_size(dev);
560 /* We allocate an extra 4K bytes to log,
561 * to reduce the * number of reallocations. */
562 #define VHOST_LOG_BUFFER (0x1000 / sizeof *dev->log)
563 /* To log more, must increase log size before table update. */
564 if (dev->log_size < log_size) {
565 vhost_dev_log_resize(dev, log_size + VHOST_LOG_BUFFER);
566 }
567 r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem);
568 if (r < 0) {
569 VHOST_OPS_DEBUG(r, "vhost_set_mem_table failed");
570 }
571 /* To log less, can only decrease log size after table update. */
572 if (dev->log_size > log_size + VHOST_LOG_BUFFER) {
573 vhost_dev_log_resize(dev, log_size);
574 }
575
576 out:
577 /* Deref the old list of sections, this must happen _after_ the
578 * vhost_set_mem_table to ensure the client isn't still using the
579 * section we're about to unref.
580 */
581 while (n_old_sections--) {
582 memory_region_unref(old_sections[n_old_sections].mr);
583 }
584 g_free(old_sections);
585 return;
586 }
587
588 /* Adds the section data to the tmp_section structure.
589 * It relies on the listener calling us in memory address order
590 * and for each region (via the _add and _nop methods) to
591 * join neighbours.
592 */
593 static void vhost_region_add_section(struct vhost_dev *dev,
594 MemoryRegionSection *section)
595 {
596 bool need_add = true;
597 uint64_t mrs_size = int128_get64(section->size);
598 uint64_t mrs_gpa = section->offset_within_address_space;
599 uintptr_t mrs_host = (uintptr_t)memory_region_get_ram_ptr(section->mr) +
600 section->offset_within_region;
601 RAMBlock *mrs_rb = section->mr->ram_block;
602
603 trace_vhost_region_add_section(section->mr->name, mrs_gpa, mrs_size,
604 mrs_host);
605
606 if (dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER) {
607 /* Round the section to it's page size */
608 /* First align the start down to a page boundary */
609 size_t mrs_page = qemu_ram_pagesize(mrs_rb);
610 uint64_t alignage = mrs_host & (mrs_page - 1);
611 if (alignage) {
612 mrs_host -= alignage;
613 mrs_size += alignage;
614 mrs_gpa -= alignage;
615 }
616 /* Now align the size up to a page boundary */
617 alignage = mrs_size & (mrs_page - 1);
618 if (alignage) {
619 mrs_size += mrs_page - alignage;
620 }
621 trace_vhost_region_add_section_aligned(section->mr->name, mrs_gpa,
622 mrs_size, mrs_host);
623 }
624
625 if (dev->n_tmp_sections) {
626 /* Since we already have at least one section, lets see if
627 * this extends it; since we're scanning in order, we only
628 * have to look at the last one, and the FlatView that calls
629 * us shouldn't have overlaps.
630 */
631 MemoryRegionSection *prev_sec = dev->tmp_sections +
632 (dev->n_tmp_sections - 1);
633 uint64_t prev_gpa_start = prev_sec->offset_within_address_space;
634 uint64_t prev_size = int128_get64(prev_sec->size);
635 uint64_t prev_gpa_end = range_get_last(prev_gpa_start, prev_size);
636 uint64_t prev_host_start =
637 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr) +
638 prev_sec->offset_within_region;
639 uint64_t prev_host_end = range_get_last(prev_host_start, prev_size);
640
641 if (mrs_gpa <= (prev_gpa_end + 1)) {
642 /* OK, looks like overlapping/intersecting - it's possible that
643 * the rounding to page sizes has made them overlap, but they should
644 * match up in the same RAMBlock if they do.
645 */
646 if (mrs_gpa < prev_gpa_start) {
647 error_report("%s:Section '%s' rounded to %"PRIx64
648 " prior to previous '%s' %"PRIx64,
649 __func__, section->mr->name, mrs_gpa,
650 prev_sec->mr->name, prev_gpa_start);
651 /* A way to cleanly fail here would be better */
652 return;
653 }
654 /* Offset from the start of the previous GPA to this GPA */
655 size_t offset = mrs_gpa - prev_gpa_start;
656
657 if (prev_host_start + offset == mrs_host &&
658 section->mr == prev_sec->mr &&
659 (!dev->vhost_ops->vhost_backend_can_merge ||
660 dev->vhost_ops->vhost_backend_can_merge(dev,
661 mrs_host, mrs_size,
662 prev_host_start, prev_size))) {
663 uint64_t max_end = MAX(prev_host_end, mrs_host + mrs_size);
664 need_add = false;
665 prev_sec->offset_within_address_space =
666 MIN(prev_gpa_start, mrs_gpa);
667 prev_sec->offset_within_region =
668 MIN(prev_host_start, mrs_host) -
669 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr);
670 prev_sec->size = int128_make64(max_end - MIN(prev_host_start,
671 mrs_host));
672 trace_vhost_region_add_section_merge(section->mr->name,
673 int128_get64(prev_sec->size),
674 prev_sec->offset_within_address_space,
675 prev_sec->offset_within_region);
676 } else {
677 /* adjoining regions are fine, but overlapping ones with
678 * different blocks/offsets shouldn't happen
679 */
680 if (mrs_gpa != prev_gpa_end + 1) {
681 error_report("%s: Overlapping but not coherent sections "
682 "at %"PRIx64,
683 __func__, mrs_gpa);
684 return;
685 }
686 }
687 }
688 }
689
690 if (need_add) {
691 ++dev->n_tmp_sections;
692 dev->tmp_sections = g_renew(MemoryRegionSection, dev->tmp_sections,
693 dev->n_tmp_sections);
694 dev->tmp_sections[dev->n_tmp_sections - 1] = *section;
695 /* The flatview isn't stable and we don't use it, making it NULL
696 * means we can memcmp the list.
697 */
698 dev->tmp_sections[dev->n_tmp_sections - 1].fv = NULL;
699 memory_region_ref(section->mr);
700 }
701 }
702
703 /* Used for both add and nop callbacks */
704 static void vhost_region_addnop(MemoryListener *listener,
705 MemoryRegionSection *section)
706 {
707 struct vhost_dev *dev = container_of(listener, struct vhost_dev,
708 memory_listener);
709
710 if (!vhost_section(dev, section)) {
711 return;
712 }
713 vhost_region_add_section(dev, section);
714 }
715
716 static void vhost_iommu_unmap_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
717 {
718 struct vhost_iommu *iommu = container_of(n, struct vhost_iommu, n);
719 struct vhost_dev *hdev = iommu->hdev;
720 hwaddr iova = iotlb->iova + iommu->iommu_offset;
721
722 if (vhost_backend_invalidate_device_iotlb(hdev, iova,
723 iotlb->addr_mask + 1)) {
724 error_report("Fail to invalidate device iotlb");
725 }
726 }
727
728 static void vhost_iommu_region_add(MemoryListener *listener,
729 MemoryRegionSection *section)
730 {
731 struct vhost_dev *dev = container_of(listener, struct vhost_dev,
732 iommu_listener);
733 struct vhost_iommu *iommu;
734 Int128 end;
735 int iommu_idx;
736 IOMMUMemoryRegion *iommu_mr;
737 int ret;
738
739 if (!memory_region_is_iommu(section->mr)) {
740 return;
741 }
742
743 iommu_mr = IOMMU_MEMORY_REGION(section->mr);
744
745 iommu = g_malloc0(sizeof(*iommu));
746 end = int128_add(int128_make64(section->offset_within_region),
747 section->size);
748 end = int128_sub(end, int128_one());
749 iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr,
750 MEMTXATTRS_UNSPECIFIED);
751 iommu_notifier_init(&iommu->n, vhost_iommu_unmap_notify,
752 IOMMU_NOTIFIER_DEVIOTLB_UNMAP,
753 section->offset_within_region,
754 int128_get64(end),
755 iommu_idx);
756 iommu->mr = section->mr;
757 iommu->iommu_offset = section->offset_within_address_space -
758 section->offset_within_region;
759 iommu->hdev = dev;
760 ret = memory_region_register_iommu_notifier(section->mr, &iommu->n, NULL);
761 if (ret) {
762 /*
763 * Some vIOMMUs do not support dev-iotlb yet. If so, try to use the
764 * UNMAP legacy message
765 */
766 iommu->n.notifier_flags = IOMMU_NOTIFIER_UNMAP;
767 memory_region_register_iommu_notifier(section->mr, &iommu->n,
768 &error_fatal);
769 }
770 QLIST_INSERT_HEAD(&dev->iommu_list, iommu, iommu_next);
771 /* TODO: can replay help performance here? */
772 }
773
774 static void vhost_iommu_region_del(MemoryListener *listener,
775 MemoryRegionSection *section)
776 {
777 struct vhost_dev *dev = container_of(listener, struct vhost_dev,
778 iommu_listener);
779 struct vhost_iommu *iommu;
780
781 if (!memory_region_is_iommu(section->mr)) {
782 return;
783 }
784
785 QLIST_FOREACH(iommu, &dev->iommu_list, iommu_next) {
786 if (iommu->mr == section->mr &&
787 iommu->n.start == section->offset_within_region) {
788 memory_region_unregister_iommu_notifier(iommu->mr,
789 &iommu->n);
790 QLIST_REMOVE(iommu, iommu_next);
791 g_free(iommu);
792 break;
793 }
794 }
795 }
796
797 static int vhost_virtqueue_set_addr(struct vhost_dev *dev,
798 struct vhost_virtqueue *vq,
799 unsigned idx, bool enable_log)
800 {
801 struct vhost_vring_addr addr;
802 int r;
803 memset(&addr, 0, sizeof(struct vhost_vring_addr));
804
805 if (dev->vhost_ops->vhost_vq_get_addr) {
806 r = dev->vhost_ops->vhost_vq_get_addr(dev, &addr, vq);
807 if (r < 0) {
808 VHOST_OPS_DEBUG(r, "vhost_vq_get_addr failed");
809 return r;
810 }
811 } else {
812 addr.desc_user_addr = (uint64_t)(unsigned long)vq->desc;
813 addr.avail_user_addr = (uint64_t)(unsigned long)vq->avail;
814 addr.used_user_addr = (uint64_t)(unsigned long)vq->used;
815 }
816 addr.index = idx;
817 addr.log_guest_addr = vq->used_phys;
818 addr.flags = enable_log ? (1 << VHOST_VRING_F_LOG) : 0;
819 r = dev->vhost_ops->vhost_set_vring_addr(dev, &addr);
820 if (r < 0) {
821 VHOST_OPS_DEBUG(r, "vhost_set_vring_addr failed");
822 }
823 return r;
824 }
825
826 static int vhost_dev_set_features(struct vhost_dev *dev,
827 bool enable_log)
828 {
829 uint64_t features = dev->acked_features;
830 int r;
831 if (enable_log) {
832 features |= 0x1ULL << VHOST_F_LOG_ALL;
833 }
834 if (!vhost_dev_has_iommu(dev)) {
835 features &= ~(0x1ULL << VIRTIO_F_IOMMU_PLATFORM);
836 }
837 if (dev->vhost_ops->vhost_force_iommu) {
838 if (dev->vhost_ops->vhost_force_iommu(dev) == true) {
839 features |= 0x1ULL << VIRTIO_F_IOMMU_PLATFORM;
840 }
841 }
842 r = dev->vhost_ops->vhost_set_features(dev, features);
843 if (r < 0) {
844 VHOST_OPS_DEBUG(r, "vhost_set_features failed");
845 goto out;
846 }
847 if (dev->vhost_ops->vhost_set_backend_cap) {
848 r = dev->vhost_ops->vhost_set_backend_cap(dev);
849 if (r < 0) {
850 VHOST_OPS_DEBUG(r, "vhost_set_backend_cap failed");
851 goto out;
852 }
853 }
854
855 out:
856 return r;
857 }
858
859 static int vhost_dev_set_log(struct vhost_dev *dev, bool enable_log)
860 {
861 int r, i, idx;
862 hwaddr addr;
863
864 r = vhost_dev_set_features(dev, enable_log);
865 if (r < 0) {
866 goto err_features;
867 }
868 for (i = 0; i < dev->nvqs; ++i) {
869 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i);
870 addr = virtio_queue_get_desc_addr(dev->vdev, idx);
871 if (!addr) {
872 /*
873 * The queue might not be ready for start. If this
874 * is the case there is no reason to continue the process.
875 * The similar logic is used by the vhost_virtqueue_start()
876 * routine.
877 */
878 continue;
879 }
880 r = vhost_virtqueue_set_addr(dev, dev->vqs + i, idx,
881 enable_log);
882 if (r < 0) {
883 goto err_vq;
884 }
885 }
886 return 0;
887 err_vq:
888 for (; i >= 0; --i) {
889 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i);
890 vhost_virtqueue_set_addr(dev, dev->vqs + i, idx,
891 dev->log_enabled);
892 }
893 vhost_dev_set_features(dev, dev->log_enabled);
894 err_features:
895 return r;
896 }
897
898 static int vhost_migration_log(MemoryListener *listener, bool enable)
899 {
900 struct vhost_dev *dev = container_of(listener, struct vhost_dev,
901 memory_listener);
902 int r;
903 if (enable == dev->log_enabled) {
904 return 0;
905 }
906 if (!dev->started) {
907 dev->log_enabled = enable;
908 return 0;
909 }
910
911 r = 0;
912 if (!enable) {
913 r = vhost_dev_set_log(dev, false);
914 if (r < 0) {
915 goto check_dev_state;
916 }
917 vhost_log_put(dev, false);
918 } else {
919 vhost_dev_log_resize(dev, vhost_get_log_size(dev));
920 r = vhost_dev_set_log(dev, true);
921 if (r < 0) {
922 goto check_dev_state;
923 }
924 }
925
926 check_dev_state:
927 dev->log_enabled = enable;
928 /*
929 * vhost-user-* devices could change their state during log
930 * initialization due to disconnect. So check dev state after
931 * vhost communication.
932 */
933 if (!dev->started) {
934 /*
935 * Since device is in the stopped state, it is okay for
936 * migration. Return success.
937 */
938 r = 0;
939 }
940 if (r) {
941 /* An error occurred. */
942 dev->log_enabled = false;
943 }
944
945 return r;
946 }
947
948 static void vhost_log_global_start(MemoryListener *listener)
949 {
950 int r;
951
952 r = vhost_migration_log(listener, true);
953 if (r < 0) {
954 abort();
955 }
956 }
957
958 static void vhost_log_global_stop(MemoryListener *listener)
959 {
960 int r;
961
962 r = vhost_migration_log(listener, false);
963 if (r < 0) {
964 abort();
965 }
966 }
967
968 static void vhost_log_start(MemoryListener *listener,
969 MemoryRegionSection *section,
970 int old, int new)
971 {
972 /* FIXME: implement */
973 }
974
975 static void vhost_log_stop(MemoryListener *listener,
976 MemoryRegionSection *section,
977 int old, int new)
978 {
979 /* FIXME: implement */
980 }
981
982 /* The vhost driver natively knows how to handle the vrings of non
983 * cross-endian legacy devices and modern devices. Only legacy devices
984 * exposed to a bi-endian guest may require the vhost driver to use a
985 * specific endianness.
986 */
987 static inline bool vhost_needs_vring_endian(VirtIODevice *vdev)
988 {
989 if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
990 return false;
991 }
992 #ifdef HOST_WORDS_BIGENDIAN
993 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_LITTLE;
994 #else
995 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
996 #endif
997 }
998
999 static int vhost_virtqueue_set_vring_endian_legacy(struct vhost_dev *dev,
1000 bool is_big_endian,
1001 int vhost_vq_index)
1002 {
1003 int r;
1004 struct vhost_vring_state s = {
1005 .index = vhost_vq_index,
1006 .num = is_big_endian
1007 };
1008
1009 r = dev->vhost_ops->vhost_set_vring_endian(dev, &s);
1010 if (r < 0) {
1011 VHOST_OPS_DEBUG(r, "vhost_set_vring_endian failed");
1012 }
1013 return r;
1014 }
1015
1016 static int vhost_memory_region_lookup(struct vhost_dev *hdev,
1017 uint64_t gpa, uint64_t *uaddr,
1018 uint64_t *len)
1019 {
1020 int i;
1021
1022 for (i = 0; i < hdev->mem->nregions; i++) {
1023 struct vhost_memory_region *reg = hdev->mem->regions + i;
1024
1025 if (gpa >= reg->guest_phys_addr &&
1026 reg->guest_phys_addr + reg->memory_size > gpa) {
1027 *uaddr = reg->userspace_addr + gpa - reg->guest_phys_addr;
1028 *len = reg->guest_phys_addr + reg->memory_size - gpa;
1029 return 0;
1030 }
1031 }
1032
1033 return -EFAULT;
1034 }
1035
1036 int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write)
1037 {
1038 IOMMUTLBEntry iotlb;
1039 uint64_t uaddr, len;
1040 int ret = -EFAULT;
1041
1042 RCU_READ_LOCK_GUARD();
1043
1044 trace_vhost_iotlb_miss(dev, 1);
1045
1046 iotlb = address_space_get_iotlb_entry(dev->vdev->dma_as,
1047 iova, write,
1048 MEMTXATTRS_UNSPECIFIED);
1049 if (iotlb.target_as != NULL) {
1050 ret = vhost_memory_region_lookup(dev, iotlb.translated_addr,
1051 &uaddr, &len);
1052 if (ret) {
1053 trace_vhost_iotlb_miss(dev, 3);
1054 error_report("Fail to lookup the translated address "
1055 "%"PRIx64, iotlb.translated_addr);
1056 goto out;
1057 }
1058
1059 len = MIN(iotlb.addr_mask + 1, len);
1060 iova = iova & ~iotlb.addr_mask;
1061
1062 ret = vhost_backend_update_device_iotlb(dev, iova, uaddr,
1063 len, iotlb.perm);
1064 if (ret) {
1065 trace_vhost_iotlb_miss(dev, 4);
1066 error_report("Fail to update device iotlb");
1067 goto out;
1068 }
1069 }
1070
1071 trace_vhost_iotlb_miss(dev, 2);
1072
1073 out:
1074 return ret;
1075 }
1076
1077 static int vhost_virtqueue_start(struct vhost_dev *dev,
1078 struct VirtIODevice *vdev,
1079 struct vhost_virtqueue *vq,
1080 unsigned idx)
1081 {
1082 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
1083 VirtioBusState *vbus = VIRTIO_BUS(qbus);
1084 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus);
1085 hwaddr s, l, a;
1086 int r;
1087 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx);
1088 struct vhost_vring_file file = {
1089 .index = vhost_vq_index
1090 };
1091 struct vhost_vring_state state = {
1092 .index = vhost_vq_index
1093 };
1094 struct VirtQueue *vvq = virtio_get_queue(vdev, idx);
1095
1096 a = virtio_queue_get_desc_addr(vdev, idx);
1097 if (a == 0) {
1098 /* Queue might not be ready for start */
1099 return 0;
1100 }
1101
1102 vq->num = state.num = virtio_queue_get_num(vdev, idx);
1103 r = dev->vhost_ops->vhost_set_vring_num(dev, &state);
1104 if (r) {
1105 VHOST_OPS_DEBUG(r, "vhost_set_vring_num failed");
1106 return r;
1107 }
1108
1109 state.num = virtio_queue_get_last_avail_idx(vdev, idx);
1110 r = dev->vhost_ops->vhost_set_vring_base(dev, &state);
1111 if (r) {
1112 VHOST_OPS_DEBUG(r, "vhost_set_vring_base failed");
1113 return r;
1114 }
1115
1116 if (vhost_needs_vring_endian(vdev)) {
1117 r = vhost_virtqueue_set_vring_endian_legacy(dev,
1118 virtio_is_big_endian(vdev),
1119 vhost_vq_index);
1120 if (r) {
1121 return r;
1122 }
1123 }
1124
1125 vq->desc_size = s = l = virtio_queue_get_desc_size(vdev, idx);
1126 vq->desc_phys = a;
1127 vq->desc = vhost_memory_map(dev, a, &l, false);
1128 if (!vq->desc || l != s) {
1129 r = -ENOMEM;
1130 goto fail_alloc_desc;
1131 }
1132 vq->avail_size = s = l = virtio_queue_get_avail_size(vdev, idx);
1133 vq->avail_phys = a = virtio_queue_get_avail_addr(vdev, idx);
1134 vq->avail = vhost_memory_map(dev, a, &l, false);
1135 if (!vq->avail || l != s) {
1136 r = -ENOMEM;
1137 goto fail_alloc_avail;
1138 }
1139 vq->used_size = s = l = virtio_queue_get_used_size(vdev, idx);
1140 vq->used_phys = a = virtio_queue_get_used_addr(vdev, idx);
1141 vq->used = vhost_memory_map(dev, a, &l, true);
1142 if (!vq->used || l != s) {
1143 r = -ENOMEM;
1144 goto fail_alloc_used;
1145 }
1146
1147 r = vhost_virtqueue_set_addr(dev, vq, vhost_vq_index, dev->log_enabled);
1148 if (r < 0) {
1149 goto fail_alloc;
1150 }
1151
1152 file.fd = event_notifier_get_fd(virtio_queue_get_host_notifier(vvq));
1153 r = dev->vhost_ops->vhost_set_vring_kick(dev, &file);
1154 if (r) {
1155 VHOST_OPS_DEBUG(r, "vhost_set_vring_kick failed");
1156 goto fail_kick;
1157 }
1158
1159 /* Clear and discard previous events if any. */
1160 event_notifier_test_and_clear(&vq->masked_notifier);
1161
1162 /* Init vring in unmasked state, unless guest_notifier_mask
1163 * will do it later.
1164 */
1165 if (!vdev->use_guest_notifier_mask) {
1166 /* TODO: check and handle errors. */
1167 vhost_virtqueue_mask(dev, vdev, idx, false);
1168 }
1169
1170 if (k->query_guest_notifiers &&
1171 k->query_guest_notifiers(qbus->parent) &&
1172 virtio_queue_vector(vdev, idx) == VIRTIO_NO_VECTOR) {
1173 file.fd = -1;
1174 r = dev->vhost_ops->vhost_set_vring_call(dev, &file);
1175 if (r) {
1176 goto fail_vector;
1177 }
1178 }
1179
1180 return 0;
1181
1182 fail_vector:
1183 fail_kick:
1184 fail_alloc:
1185 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx),
1186 0, 0);
1187 fail_alloc_used:
1188 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx),
1189 0, 0);
1190 fail_alloc_avail:
1191 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx),
1192 0, 0);
1193 fail_alloc_desc:
1194 return r;
1195 }
1196
1197 static void vhost_virtqueue_stop(struct vhost_dev *dev,
1198 struct VirtIODevice *vdev,
1199 struct vhost_virtqueue *vq,
1200 unsigned idx)
1201 {
1202 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx);
1203 struct vhost_vring_state state = {
1204 .index = vhost_vq_index,
1205 };
1206 int r;
1207
1208 if (virtio_queue_get_desc_addr(vdev, idx) == 0) {
1209 /* Don't stop the virtqueue which might have not been started */
1210 return;
1211 }
1212
1213 r = dev->vhost_ops->vhost_get_vring_base(dev, &state);
1214 if (r < 0) {
1215 VHOST_OPS_DEBUG(r, "vhost VQ %u ring restore failed: %d", idx, r);
1216 /* Connection to the backend is broken, so let's sync internal
1217 * last avail idx to the device used idx.
1218 */
1219 virtio_queue_restore_last_avail_idx(vdev, idx);
1220 } else {
1221 virtio_queue_set_last_avail_idx(vdev, idx, state.num);
1222 }
1223 virtio_queue_invalidate_signalled_used(vdev, idx);
1224 virtio_queue_update_used_idx(vdev, idx);
1225
1226 /* In the cross-endian case, we need to reset the vring endianness to
1227 * native as legacy devices expect so by default.
1228 */
1229 if (vhost_needs_vring_endian(vdev)) {
1230 vhost_virtqueue_set_vring_endian_legacy(dev,
1231 !virtio_is_big_endian(vdev),
1232 vhost_vq_index);
1233 }
1234
1235 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx),
1236 1, virtio_queue_get_used_size(vdev, idx));
1237 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx),
1238 0, virtio_queue_get_avail_size(vdev, idx));
1239 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx),
1240 0, virtio_queue_get_desc_size(vdev, idx));
1241 }
1242
1243 static void vhost_eventfd_add(MemoryListener *listener,
1244 MemoryRegionSection *section,
1245 bool match_data, uint64_t data, EventNotifier *e)
1246 {
1247 }
1248
1249 static void vhost_eventfd_del(MemoryListener *listener,
1250 MemoryRegionSection *section,
1251 bool match_data, uint64_t data, EventNotifier *e)
1252 {
1253 }
1254
1255 static int vhost_virtqueue_set_busyloop_timeout(struct vhost_dev *dev,
1256 int n, uint32_t timeout)
1257 {
1258 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n);
1259 struct vhost_vring_state state = {
1260 .index = vhost_vq_index,
1261 .num = timeout,
1262 };
1263 int r;
1264
1265 if (!dev->vhost_ops->vhost_set_vring_busyloop_timeout) {
1266 return -EINVAL;
1267 }
1268
1269 r = dev->vhost_ops->vhost_set_vring_busyloop_timeout(dev, &state);
1270 if (r) {
1271 VHOST_OPS_DEBUG(r, "vhost_set_vring_busyloop_timeout failed");
1272 return r;
1273 }
1274
1275 return 0;
1276 }
1277
1278 static int vhost_virtqueue_init(struct vhost_dev *dev,
1279 struct vhost_virtqueue *vq, int n)
1280 {
1281 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n);
1282 struct vhost_vring_file file = {
1283 .index = vhost_vq_index,
1284 };
1285 int r = event_notifier_init(&vq->masked_notifier, 0);
1286 if (r < 0) {
1287 return r;
1288 }
1289
1290 file.fd = event_notifier_get_fd(&vq->masked_notifier);
1291 r = dev->vhost_ops->vhost_set_vring_call(dev, &file);
1292 if (r) {
1293 VHOST_OPS_DEBUG(r, "vhost_set_vring_call failed");
1294 goto fail_call;
1295 }
1296
1297 vq->dev = dev;
1298
1299 return 0;
1300 fail_call:
1301 event_notifier_cleanup(&vq->masked_notifier);
1302 return r;
1303 }
1304
1305 static void vhost_virtqueue_cleanup(struct vhost_virtqueue *vq)
1306 {
1307 event_notifier_cleanup(&vq->masked_notifier);
1308 }
1309
1310 int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
1311 VhostBackendType backend_type, uint32_t busyloop_timeout,
1312 Error **errp)
1313 {
1314 uint64_t features;
1315 int i, r, n_initialized_vqs = 0;
1316
1317 hdev->vdev = NULL;
1318 hdev->migration_blocker = NULL;
1319
1320 r = vhost_set_backend_type(hdev, backend_type);
1321 assert(r >= 0);
1322
1323 r = hdev->vhost_ops->vhost_backend_init(hdev, opaque, errp);
1324 if (r < 0) {
1325 goto fail;
1326 }
1327
1328 r = hdev->vhost_ops->vhost_set_owner(hdev);
1329 if (r < 0) {
1330 error_setg_errno(errp, -r, "vhost_set_owner failed");
1331 goto fail;
1332 }
1333
1334 r = hdev->vhost_ops->vhost_get_features(hdev, &features);
1335 if (r < 0) {
1336 error_setg_errno(errp, -r, "vhost_get_features failed");
1337 goto fail;
1338 }
1339
1340 for (i = 0; i < hdev->nvqs; ++i, ++n_initialized_vqs) {
1341 r = vhost_virtqueue_init(hdev, hdev->vqs + i, hdev->vq_index + i);
1342 if (r < 0) {
1343 error_setg_errno(errp, -r, "Failed to initialize virtqueue %d", i);
1344 goto fail;
1345 }
1346 }
1347
1348 if (busyloop_timeout) {
1349 for (i = 0; i < hdev->nvqs; ++i) {
1350 r = vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i,
1351 busyloop_timeout);
1352 if (r < 0) {
1353 error_setg_errno(errp, -r, "Failed to set busyloop timeout");
1354 goto fail_busyloop;
1355 }
1356 }
1357 }
1358
1359 hdev->features = features;
1360
1361 hdev->memory_listener = (MemoryListener) {
1362 .name = "vhost",
1363 .begin = vhost_begin,
1364 .commit = vhost_commit,
1365 .region_add = vhost_region_addnop,
1366 .region_nop = vhost_region_addnop,
1367 .log_start = vhost_log_start,
1368 .log_stop = vhost_log_stop,
1369 .log_sync = vhost_log_sync,
1370 .log_global_start = vhost_log_global_start,
1371 .log_global_stop = vhost_log_global_stop,
1372 .eventfd_add = vhost_eventfd_add,
1373 .eventfd_del = vhost_eventfd_del,
1374 .priority = 10
1375 };
1376
1377 hdev->iommu_listener = (MemoryListener) {
1378 .name = "vhost-iommu",
1379 .region_add = vhost_iommu_region_add,
1380 .region_del = vhost_iommu_region_del,
1381 };
1382
1383 if (hdev->migration_blocker == NULL) {
1384 if (!(hdev->features & (0x1ULL << VHOST_F_LOG_ALL))) {
1385 error_setg(&hdev->migration_blocker,
1386 "Migration disabled: vhost lacks VHOST_F_LOG_ALL feature.");
1387 } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_alloc_check()) {
1388 error_setg(&hdev->migration_blocker,
1389 "Migration disabled: failed to allocate shared memory");
1390 }
1391 }
1392
1393 if (hdev->migration_blocker != NULL) {
1394 r = migrate_add_blocker(hdev->migration_blocker, errp);
1395 if (r < 0) {
1396 error_free(hdev->migration_blocker);
1397 goto fail_busyloop;
1398 }
1399 }
1400
1401 hdev->mem = g_malloc0(offsetof(struct vhost_memory, regions));
1402 hdev->n_mem_sections = 0;
1403 hdev->mem_sections = NULL;
1404 hdev->log = NULL;
1405 hdev->log_size = 0;
1406 hdev->log_enabled = false;
1407 hdev->started = false;
1408 memory_listener_register(&hdev->memory_listener, &address_space_memory);
1409 QLIST_INSERT_HEAD(&vhost_devices, hdev, entry);
1410
1411 if (used_memslots > hdev->vhost_ops->vhost_backend_memslots_limit(hdev)) {
1412 error_setg(errp, "vhost backend memory slots limit is less"
1413 " than current number of present memory slots");
1414 r = -EINVAL;
1415 goto fail_busyloop;
1416 }
1417
1418 return 0;
1419
1420 fail_busyloop:
1421 if (busyloop_timeout) {
1422 while (--i >= 0) {
1423 vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 0);
1424 }
1425 }
1426 fail:
1427 hdev->nvqs = n_initialized_vqs;
1428 vhost_dev_cleanup(hdev);
1429 return r;
1430 }
1431
1432 void vhost_dev_cleanup(struct vhost_dev *hdev)
1433 {
1434 int i;
1435
1436 for (i = 0; i < hdev->nvqs; ++i) {
1437 vhost_virtqueue_cleanup(hdev->vqs + i);
1438 }
1439 if (hdev->mem) {
1440 /* those are only safe after successful init */
1441 memory_listener_unregister(&hdev->memory_listener);
1442 QLIST_REMOVE(hdev, entry);
1443 }
1444 if (hdev->migration_blocker) {
1445 migrate_del_blocker(hdev->migration_blocker);
1446 error_free(hdev->migration_blocker);
1447 }
1448 g_free(hdev->mem);
1449 g_free(hdev->mem_sections);
1450 if (hdev->vhost_ops) {
1451 hdev->vhost_ops->vhost_backend_cleanup(hdev);
1452 }
1453 assert(!hdev->log);
1454
1455 memset(hdev, 0, sizeof(struct vhost_dev));
1456 }
1457
1458 /* Stop processing guest IO notifications in qemu.
1459 * Start processing them in vhost in kernel.
1460 */
1461 int vhost_dev_enable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev)
1462 {
1463 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
1464 int i, r, e;
1465
1466 /* We will pass the notifiers to the kernel, make sure that QEMU
1467 * doesn't interfere.
1468 */
1469 r = virtio_device_grab_ioeventfd(vdev);
1470 if (r < 0) {
1471 error_report("binding does not support host notifiers");
1472 goto fail;
1473 }
1474
1475 for (i = 0; i < hdev->nvqs; ++i) {
1476 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i,
1477 true);
1478 if (r < 0) {
1479 error_report("vhost VQ %d notifier binding failed: %d", i, -r);
1480 goto fail_vq;
1481 }
1482 }
1483
1484 return 0;
1485 fail_vq:
1486 while (--i >= 0) {
1487 e = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i,
1488 false);
1489 if (e < 0) {
1490 error_report("vhost VQ %d notifier cleanup error: %d", i, -r);
1491 }
1492 assert (e >= 0);
1493 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i);
1494 }
1495 virtio_device_release_ioeventfd(vdev);
1496 fail:
1497 return r;
1498 }
1499
1500 /* Stop processing guest IO notifications in vhost.
1501 * Start processing them in qemu.
1502 * This might actually run the qemu handlers right away,
1503 * so virtio in qemu must be completely setup when this is called.
1504 */
1505 void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev)
1506 {
1507 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
1508 int i, r;
1509
1510 for (i = 0; i < hdev->nvqs; ++i) {
1511 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i,
1512 false);
1513 if (r < 0) {
1514 error_report("vhost VQ %d notifier cleanup failed: %d", i, -r);
1515 }
1516 assert (r >= 0);
1517 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i);
1518 }
1519 virtio_device_release_ioeventfd(vdev);
1520 }
1521
1522 /* Test and clear event pending status.
1523 * Should be called after unmask to avoid losing events.
1524 */
1525 bool vhost_virtqueue_pending(struct vhost_dev *hdev, int n)
1526 {
1527 struct vhost_virtqueue *vq = hdev->vqs + n - hdev->vq_index;
1528 assert(n >= hdev->vq_index && n < hdev->vq_index + hdev->nvqs);
1529 return event_notifier_test_and_clear(&vq->masked_notifier);
1530 }
1531
1532 /* Mask/unmask events from this vq. */
1533 void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n,
1534 bool mask)
1535 {
1536 struct VirtQueue *vvq = virtio_get_queue(vdev, n);
1537 int r, index = n - hdev->vq_index;
1538 struct vhost_vring_file file;
1539
1540 /* should only be called after backend is connected */
1541 assert(hdev->vhost_ops);
1542
1543 if (mask) {
1544 assert(vdev->use_guest_notifier_mask);
1545 file.fd = event_notifier_get_fd(&hdev->vqs[index].masked_notifier);
1546 } else {
1547 file.fd = event_notifier_get_fd(virtio_queue_get_guest_notifier(vvq));
1548 }
1549
1550 file.index = hdev->vhost_ops->vhost_get_vq_index(hdev, n);
1551 r = hdev->vhost_ops->vhost_set_vring_call(hdev, &file);
1552 if (r < 0) {
1553 VHOST_OPS_DEBUG(r, "vhost_set_vring_call failed");
1554 }
1555 }
1556
1557 uint64_t vhost_get_features(struct vhost_dev *hdev, const int *feature_bits,
1558 uint64_t features)
1559 {
1560 const int *bit = feature_bits;
1561 while (*bit != VHOST_INVALID_FEATURE_BIT) {
1562 uint64_t bit_mask = (1ULL << *bit);
1563 if (!(hdev->features & bit_mask)) {
1564 features &= ~bit_mask;
1565 }
1566 bit++;
1567 }
1568 return features;
1569 }
1570
1571 void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits,
1572 uint64_t features)
1573 {
1574 const int *bit = feature_bits;
1575 while (*bit != VHOST_INVALID_FEATURE_BIT) {
1576 uint64_t bit_mask = (1ULL << *bit);
1577 if (features & bit_mask) {
1578 hdev->acked_features |= bit_mask;
1579 }
1580 bit++;
1581 }
1582 }
1583
1584 int vhost_dev_get_config(struct vhost_dev *hdev, uint8_t *config,
1585 uint32_t config_len, Error **errp)
1586 {
1587 assert(hdev->vhost_ops);
1588
1589 if (hdev->vhost_ops->vhost_get_config) {
1590 return hdev->vhost_ops->vhost_get_config(hdev, config, config_len,
1591 errp);
1592 }
1593
1594 error_setg(errp, "vhost_get_config not implemented");
1595 return -ENOSYS;
1596 }
1597
1598 int vhost_dev_set_config(struct vhost_dev *hdev, const uint8_t *data,
1599 uint32_t offset, uint32_t size, uint32_t flags)
1600 {
1601 assert(hdev->vhost_ops);
1602
1603 if (hdev->vhost_ops->vhost_set_config) {
1604 return hdev->vhost_ops->vhost_set_config(hdev, data, offset,
1605 size, flags);
1606 }
1607
1608 return -ENOSYS;
1609 }
1610
1611 void vhost_dev_set_config_notifier(struct vhost_dev *hdev,
1612 const VhostDevConfigOps *ops)
1613 {
1614 hdev->config_ops = ops;
1615 }
1616
1617 void vhost_dev_free_inflight(struct vhost_inflight *inflight)
1618 {
1619 if (inflight && inflight->addr) {
1620 qemu_memfd_free(inflight->addr, inflight->size, inflight->fd);
1621 inflight->addr = NULL;
1622 inflight->fd = -1;
1623 }
1624 }
1625
1626 static int vhost_dev_resize_inflight(struct vhost_inflight *inflight,
1627 uint64_t new_size)
1628 {
1629 Error *err = NULL;
1630 int fd = -1;
1631 void *addr = qemu_memfd_alloc("vhost-inflight", new_size,
1632 F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL,
1633 &fd, &err);
1634
1635 if (err) {
1636 error_report_err(err);
1637 return -ENOMEM;
1638 }
1639
1640 vhost_dev_free_inflight(inflight);
1641 inflight->offset = 0;
1642 inflight->addr = addr;
1643 inflight->fd = fd;
1644 inflight->size = new_size;
1645
1646 return 0;
1647 }
1648
1649 void vhost_dev_save_inflight(struct vhost_inflight *inflight, QEMUFile *f)
1650 {
1651 if (inflight->addr) {
1652 qemu_put_be64(f, inflight->size);
1653 qemu_put_be16(f, inflight->queue_size);
1654 qemu_put_buffer(f, inflight->addr, inflight->size);
1655 } else {
1656 qemu_put_be64(f, 0);
1657 }
1658 }
1659
1660 int vhost_dev_load_inflight(struct vhost_inflight *inflight, QEMUFile *f)
1661 {
1662 uint64_t size;
1663
1664 size = qemu_get_be64(f);
1665 if (!size) {
1666 return 0;
1667 }
1668
1669 if (inflight->size != size) {
1670 int ret = vhost_dev_resize_inflight(inflight, size);
1671 if (ret < 0) {
1672 return ret;
1673 }
1674 }
1675 inflight->queue_size = qemu_get_be16(f);
1676
1677 qemu_get_buffer(f, inflight->addr, size);
1678
1679 return 0;
1680 }
1681
1682 int vhost_dev_prepare_inflight(struct vhost_dev *hdev, VirtIODevice *vdev)
1683 {
1684 int r;
1685
1686 if (hdev->vhost_ops->vhost_get_inflight_fd == NULL ||
1687 hdev->vhost_ops->vhost_set_inflight_fd == NULL) {
1688 return 0;
1689 }
1690
1691 hdev->vdev = vdev;
1692
1693 r = vhost_dev_set_features(hdev, hdev->log_enabled);
1694 if (r < 0) {
1695 VHOST_OPS_DEBUG(r, "vhost_dev_prepare_inflight failed");
1696 return r;
1697 }
1698
1699 return 0;
1700 }
1701
1702 int vhost_dev_set_inflight(struct vhost_dev *dev,
1703 struct vhost_inflight *inflight)
1704 {
1705 int r;
1706
1707 if (dev->vhost_ops->vhost_set_inflight_fd && inflight->addr) {
1708 r = dev->vhost_ops->vhost_set_inflight_fd(dev, inflight);
1709 if (r) {
1710 VHOST_OPS_DEBUG(r, "vhost_set_inflight_fd failed");
1711 return r;
1712 }
1713 }
1714
1715 return 0;
1716 }
1717
1718 int vhost_dev_get_inflight(struct vhost_dev *dev, uint16_t queue_size,
1719 struct vhost_inflight *inflight)
1720 {
1721 int r;
1722
1723 if (dev->vhost_ops->vhost_get_inflight_fd) {
1724 r = dev->vhost_ops->vhost_get_inflight_fd(dev, queue_size, inflight);
1725 if (r) {
1726 VHOST_OPS_DEBUG(r, "vhost_get_inflight_fd failed");
1727 return r;
1728 }
1729 }
1730
1731 return 0;
1732 }
1733
1734 /* Host notifiers must be enabled at this point. */
1735 int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev)
1736 {
1737 int i, r;
1738
1739 /* should only be called after backend is connected */
1740 assert(hdev->vhost_ops);
1741
1742 hdev->started = true;
1743 hdev->vdev = vdev;
1744
1745 r = vhost_dev_set_features(hdev, hdev->log_enabled);
1746 if (r < 0) {
1747 goto fail_features;
1748 }
1749
1750 if (vhost_dev_has_iommu(hdev)) {
1751 memory_listener_register(&hdev->iommu_listener, vdev->dma_as);
1752 }
1753
1754 r = hdev->vhost_ops->vhost_set_mem_table(hdev, hdev->mem);
1755 if (r < 0) {
1756 VHOST_OPS_DEBUG(r, "vhost_set_mem_table failed");
1757 goto fail_mem;
1758 }
1759 for (i = 0; i < hdev->nvqs; ++i) {
1760 r = vhost_virtqueue_start(hdev,
1761 vdev,
1762 hdev->vqs + i,
1763 hdev->vq_index + i);
1764 if (r < 0) {
1765 goto fail_vq;
1766 }
1767 }
1768
1769 if (hdev->log_enabled) {
1770 uint64_t log_base;
1771
1772 hdev->log_size = vhost_get_log_size(hdev);
1773 hdev->log = vhost_log_get(hdev->log_size,
1774 vhost_dev_log_is_shared(hdev));
1775 log_base = (uintptr_t)hdev->log->log;
1776 r = hdev->vhost_ops->vhost_set_log_base(hdev,
1777 hdev->log_size ? log_base : 0,
1778 hdev->log);
1779 if (r < 0) {
1780 VHOST_OPS_DEBUG(r, "vhost_set_log_base failed");
1781 goto fail_log;
1782 }
1783 }
1784 if (hdev->vhost_ops->vhost_dev_start) {
1785 r = hdev->vhost_ops->vhost_dev_start(hdev, true);
1786 if (r) {
1787 goto fail_log;
1788 }
1789 }
1790 if (vhost_dev_has_iommu(hdev) &&
1791 hdev->vhost_ops->vhost_set_iotlb_callback) {
1792 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, true);
1793
1794 /* Update used ring information for IOTLB to work correctly,
1795 * vhost-kernel code requires for this.*/
1796 for (i = 0; i < hdev->nvqs; ++i) {
1797 struct vhost_virtqueue *vq = hdev->vqs + i;
1798 vhost_device_iotlb_miss(hdev, vq->used_phys, true);
1799 }
1800 }
1801 return 0;
1802 fail_log:
1803 vhost_log_put(hdev, false);
1804 fail_vq:
1805 while (--i >= 0) {
1806 vhost_virtqueue_stop(hdev,
1807 vdev,
1808 hdev->vqs + i,
1809 hdev->vq_index + i);
1810 }
1811
1812 fail_mem:
1813 fail_features:
1814
1815 hdev->started = false;
1816 return r;
1817 }
1818
1819 /* Host notifiers must be enabled at this point. */
1820 void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev)
1821 {
1822 int i;
1823
1824 /* should only be called after backend is connected */
1825 assert(hdev->vhost_ops);
1826
1827 if (hdev->vhost_ops->vhost_dev_start) {
1828 hdev->vhost_ops->vhost_dev_start(hdev, false);
1829 }
1830 for (i = 0; i < hdev->nvqs; ++i) {
1831 vhost_virtqueue_stop(hdev,
1832 vdev,
1833 hdev->vqs + i,
1834 hdev->vq_index + i);
1835 }
1836
1837 if (vhost_dev_has_iommu(hdev)) {
1838 if (hdev->vhost_ops->vhost_set_iotlb_callback) {
1839 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, false);
1840 }
1841 memory_listener_unregister(&hdev->iommu_listener);
1842 }
1843 vhost_log_put(hdev, true);
1844 hdev->started = false;
1845 hdev->vdev = NULL;
1846 }
1847
1848 int vhost_net_set_backend(struct vhost_dev *hdev,
1849 struct vhost_vring_file *file)
1850 {
1851 if (hdev->vhost_ops->vhost_net_set_backend) {
1852 return hdev->vhost_ops->vhost_net_set_backend(hdev, file);
1853 }
1854
1855 return -ENOSYS;
1856 }