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