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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

    
13
#include <sys/ioctl.h>
14
#include <sys/eventfd.h>
15
#include "vhost.h"
16
#include "hw/hw.h"
17
/* For range_get_last */
18
#include "pci.h"
19
#include <linux/vhost.h>
20

    
21
static void vhost_dev_sync_region(struct vhost_dev *dev,
22
                                  uint64_t mfirst, uint64_t mlast,
23
                                  uint64_t rfirst, uint64_t rlast)
24
{
25
    uint64_t start = MAX(mfirst, rfirst);
26
    uint64_t end = MIN(mlast, rlast);
27
    vhost_log_chunk_t *from = dev->log + start / VHOST_LOG_CHUNK;
28
    vhost_log_chunk_t *to = dev->log + end / VHOST_LOG_CHUNK + 1;
29
    uint64_t addr = (start / VHOST_LOG_CHUNK) * VHOST_LOG_CHUNK;
30

    
31
    assert(end / VHOST_LOG_CHUNK < dev->log_size);
32
    assert(start / VHOST_LOG_CHUNK < dev->log_size);
33
    if (end < start) {
34
        return;
35
    }
36
    for (;from < to; ++from) {
37
        vhost_log_chunk_t log;
38
        int bit;
39
        /* We first check with non-atomic: much cheaper,
40
         * and we expect non-dirty to be the common case. */
41
        if (!*from) {
42
            continue;
43
        }
44
        /* Data must be read atomically. We don't really
45
         * need the barrier semantics of __sync
46
         * builtins, but it's easier to use them than
47
         * roll our own. */
48
        log = __sync_fetch_and_and(from, 0);
49
        while ((bit = sizeof(log) > sizeof(int) ?
50
                ffsll(log) : ffs(log))) {
51
            bit -= 1;
52
            cpu_physical_memory_set_dirty(addr + bit * VHOST_LOG_PAGE);
53
            log &= ~(0x1ull << bit);
54
        }
55
        addr += VHOST_LOG_CHUNK;
56
    }
57
}
58

    
59
static int vhost_client_sync_dirty_bitmap(CPUPhysMemoryClient *client,
60
                                          target_phys_addr_t start_addr,
61
                                          target_phys_addr_t end_addr)
62
{
63
    struct vhost_dev *dev = container_of(client, struct vhost_dev, client);
64
    int i;
65
    if (!dev->log_enabled || !dev->started) {
66
        return 0;
67
    }
68
    for (i = 0; i < dev->mem->nregions; ++i) {
69
        struct vhost_memory_region *reg = dev->mem->regions + i;
70
        vhost_dev_sync_region(dev, start_addr, end_addr,
71
                              reg->guest_phys_addr,
72
                              range_get_last(reg->guest_phys_addr,
73
                                             reg->memory_size));
74
    }
75
    for (i = 0; i < dev->nvqs; ++i) {
76
        struct vhost_virtqueue *vq = dev->vqs + i;
77
        vhost_dev_sync_region(dev, start_addr, end_addr, vq->used_phys,
78
                              range_get_last(vq->used_phys, vq->used_size));
79
    }
80
    return 0;
81
}
82

    
83
/* Assign/unassign. Keep an unsorted array of non-overlapping
84
 * memory regions in dev->mem. */
85
static void vhost_dev_unassign_memory(struct vhost_dev *dev,
86
                                      uint64_t start_addr,
87
                                      uint64_t size)
88
{
89
    int from, to, n = dev->mem->nregions;
90
    /* Track overlapping/split regions for sanity checking. */
91
    int overlap_start = 0, overlap_end = 0, overlap_middle = 0, split = 0;
92

    
93
    for (from = 0, to = 0; from < n; ++from, ++to) {
94
        struct vhost_memory_region *reg = dev->mem->regions + to;
95
        uint64_t reglast;
96
        uint64_t memlast;
97
        uint64_t change;
98

    
99
        /* clone old region */
100
        if (to != from) {
101
            memcpy(reg, dev->mem->regions + from, sizeof *reg);
102
        }
103

    
104
        /* No overlap is simple */
105
        if (!ranges_overlap(reg->guest_phys_addr, reg->memory_size,
106
                            start_addr, size)) {
107
            continue;
108
        }
109

    
110
        /* Split only happens if supplied region
111
         * is in the middle of an existing one. Thus it can not
112
         * overlap with any other existing region. */
113
        assert(!split);
114

    
115
        reglast = range_get_last(reg->guest_phys_addr, reg->memory_size);
116
        memlast = range_get_last(start_addr, size);
117

    
118
        /* Remove whole region */
119
        if (start_addr <= reg->guest_phys_addr && memlast >= reglast) {
120
            --dev->mem->nregions;
121
            --to;
122
            assert(to >= 0);
123
            ++overlap_middle;
124
            continue;
125
        }
126

    
127
        /* Shrink region */
128
        if (memlast >= reglast) {
129
            reg->memory_size = start_addr - reg->guest_phys_addr;
130
            assert(reg->memory_size);
131
            assert(!overlap_end);
132
            ++overlap_end;
133
            continue;
134
        }
135

    
136
        /* Shift region */
137
        if (start_addr <= reg->guest_phys_addr) {
138
            change = memlast + 1 - reg->guest_phys_addr;
139
            reg->memory_size -= change;
140
            reg->guest_phys_addr += change;
141
            reg->userspace_addr += change;
142
            assert(reg->memory_size);
143
            assert(!overlap_start);
144
            ++overlap_start;
145
            continue;
146
        }
147

    
148
        /* This only happens if supplied region
149
         * is in the middle of an existing one. Thus it can not
150
         * overlap with any other existing region. */
151
        assert(!overlap_start);
152
        assert(!overlap_end);
153
        assert(!overlap_middle);
154
        /* Split region: shrink first part, shift second part. */
155
        memcpy(dev->mem->regions + n, reg, sizeof *reg);
156
        reg->memory_size = start_addr - reg->guest_phys_addr;
157
        assert(reg->memory_size);
158
        change = memlast + 1 - reg->guest_phys_addr;
159
        reg = dev->mem->regions + n;
160
        reg->memory_size -= change;
161
        assert(reg->memory_size);
162
        reg->guest_phys_addr += change;
163
        reg->userspace_addr += change;
164
        /* Never add more than 1 region */
165
        assert(dev->mem->nregions == n);
166
        ++dev->mem->nregions;
167
        ++split;
168
    }
169
}
170

    
171
/* Called after unassign, so no regions overlap the given range. */
172
static void vhost_dev_assign_memory(struct vhost_dev *dev,
173
                                    uint64_t start_addr,
174
                                    uint64_t size,
175
                                    uint64_t uaddr)
176
{
177
    int from, to;
178
    struct vhost_memory_region *merged = NULL;
179
    for (from = 0, to = 0; from < dev->mem->nregions; ++from, ++to) {
180
        struct vhost_memory_region *reg = dev->mem->regions + to;
181
        uint64_t prlast, urlast;
182
        uint64_t pmlast, umlast;
183
        uint64_t s, e, u;
184

    
185
        /* clone old region */
186
        if (to != from) {
187
            memcpy(reg, dev->mem->regions + from, sizeof *reg);
188
        }
189
        prlast = range_get_last(reg->guest_phys_addr, reg->memory_size);
190
        pmlast = range_get_last(start_addr, size);
191
        urlast = range_get_last(reg->userspace_addr, reg->memory_size);
192
        umlast = range_get_last(uaddr, size);
193

    
194
        /* check for overlapping regions: should never happen. */
195
        assert(prlast < start_addr || pmlast < reg->guest_phys_addr);
196
        /* Not an adjacent or overlapping region - do not merge. */
197
        if ((prlast + 1 != start_addr || urlast + 1 != uaddr) &&
198
            (pmlast + 1 != reg->guest_phys_addr ||
199
             umlast + 1 != reg->userspace_addr)) {
200
            continue;
201
        }
202

    
203
        if (merged) {
204
            --to;
205
            assert(to >= 0);
206
        } else {
207
            merged = reg;
208
        }
209
        u = MIN(uaddr, reg->userspace_addr);
210
        s = MIN(start_addr, reg->guest_phys_addr);
211
        e = MAX(pmlast, prlast);
212
        uaddr = merged->userspace_addr = u;
213
        start_addr = merged->guest_phys_addr = s;
214
        size = merged->memory_size = e - s + 1;
215
        assert(merged->memory_size);
216
    }
217

    
218
    if (!merged) {
219
        struct vhost_memory_region *reg = dev->mem->regions + to;
220
        memset(reg, 0, sizeof *reg);
221
        reg->memory_size = size;
222
        assert(reg->memory_size);
223
        reg->guest_phys_addr = start_addr;
224
        reg->userspace_addr = uaddr;
225
        ++to;
226
    }
227
    assert(to <= dev->mem->nregions + 1);
228
    dev->mem->nregions = to;
229
}
230

    
231
static uint64_t vhost_get_log_size(struct vhost_dev *dev)
232
{
233
    uint64_t log_size = 0;
234
    int i;
235
    for (i = 0; i < dev->mem->nregions; ++i) {
236
        struct vhost_memory_region *reg = dev->mem->regions + i;
237
        uint64_t last = range_get_last(reg->guest_phys_addr,
238
                                       reg->memory_size);
239
        log_size = MAX(log_size, last / VHOST_LOG_CHUNK + 1);
240
    }
241
    for (i = 0; i < dev->nvqs; ++i) {
242
        struct vhost_virtqueue *vq = dev->vqs + i;
243
        uint64_t last = vq->used_phys + vq->used_size - 1;
244
        log_size = MAX(log_size, last / VHOST_LOG_CHUNK + 1);
245
    }
246
    return log_size;
247
}
248

    
249
static inline void vhost_dev_log_resize(struct vhost_dev* dev, uint64_t size)
250
{
251
    vhost_log_chunk_t *log;
252
    uint64_t log_base;
253
    int r;
254
    if (size) {
255
        log = qemu_mallocz(size * sizeof *log);
256
    } else {
257
        log = NULL;
258
    }
259
    log_base = (uint64_t)(unsigned long)log;
260
    r = ioctl(dev->control, VHOST_SET_LOG_BASE, &log_base);
261
    assert(r >= 0);
262
    vhost_client_sync_dirty_bitmap(&dev->client, 0,
263
                                   (target_phys_addr_t)~0x0ull);
264
    if (dev->log) {
265
        qemu_free(dev->log);
266
    }
267
    dev->log = log;
268
    dev->log_size = size;
269
}
270

    
271
static int vhost_verify_ring_mappings(struct vhost_dev *dev,
272
                                      uint64_t start_addr,
273
                                      uint64_t size)
274
{
275
    int i;
276
    for (i = 0; i < dev->nvqs; ++i) {
277
        struct vhost_virtqueue *vq = dev->vqs + i;
278
        target_phys_addr_t l;
279
        void *p;
280

    
281
        if (!ranges_overlap(start_addr, size, vq->ring_phys, vq->ring_size)) {
282
            continue;
283
        }
284
        l = vq->ring_size;
285
        p = cpu_physical_memory_map(vq->ring_phys, &l, 1);
286
        if (!p || l != vq->ring_size) {
287
            fprintf(stderr, "Unable to map ring buffer for ring %d\n", i);
288
            return -ENOMEM;
289
        }
290
        if (p != vq->ring) {
291
            fprintf(stderr, "Ring buffer relocated for ring %d\n", i);
292
            return -EBUSY;
293
        }
294
        cpu_physical_memory_unmap(p, l, 0, 0);
295
    }
296
    return 0;
297
}
298

    
299
static void vhost_client_set_memory(CPUPhysMemoryClient *client,
300
                                    target_phys_addr_t start_addr,
301
                                    ram_addr_t size,
302
                                    ram_addr_t phys_offset)
303
{
304
    struct vhost_dev *dev = container_of(client, struct vhost_dev, client);
305
    ram_addr_t flags = phys_offset & ~TARGET_PAGE_MASK;
306
    int s = offsetof(struct vhost_memory, regions) +
307
        (dev->mem->nregions + 1) * sizeof dev->mem->regions[0];
308
    uint64_t log_size;
309
    int r;
310
    dev->mem = qemu_realloc(dev->mem, s);
311

    
312
    assert(size);
313

    
314
    vhost_dev_unassign_memory(dev, start_addr, size);
315
    if (flags == IO_MEM_RAM) {
316
        /* Add given mapping, merging adjacent regions if any */
317
        vhost_dev_assign_memory(dev, start_addr, size,
318
                                (uintptr_t)qemu_get_ram_ptr(phys_offset));
319
    } else {
320
        /* Remove old mapping for this memory, if any. */
321
        vhost_dev_unassign_memory(dev, start_addr, size);
322
    }
323

    
324
    if (!dev->started) {
325
        return;
326
    }
327

    
328
    if (dev->started) {
329
        r = vhost_verify_ring_mappings(dev, start_addr, size);
330
        assert(r >= 0);
331
    }
332

    
333
    if (!dev->log_enabled) {
334
        r = ioctl(dev->control, VHOST_SET_MEM_TABLE, dev->mem);
335
        assert(r >= 0);
336
        return;
337
    }
338
    log_size = vhost_get_log_size(dev);
339
    /* We allocate an extra 4K bytes to log,
340
     * to reduce the * number of reallocations. */
341
#define VHOST_LOG_BUFFER (0x1000 / sizeof *dev->log)
342
    /* To log more, must increase log size before table update. */
343
    if (dev->log_size < log_size) {
344
        vhost_dev_log_resize(dev, log_size + VHOST_LOG_BUFFER);
345
    }
346
    r = ioctl(dev->control, VHOST_SET_MEM_TABLE, dev->mem);
347
    assert(r >= 0);
348
    /* To log less, can only decrease log size after table update. */
349
    if (dev->log_size > log_size + VHOST_LOG_BUFFER) {
350
        vhost_dev_log_resize(dev, log_size);
351
    }
352
}
353

    
354
static int vhost_virtqueue_set_addr(struct vhost_dev *dev,
355
                                    struct vhost_virtqueue *vq,
356
                                    unsigned idx, bool enable_log)
357
{
358
    struct vhost_vring_addr addr = {
359
        .index = idx,
360
        .desc_user_addr = (uint64_t)(unsigned long)vq->desc,
361
        .avail_user_addr = (uint64_t)(unsigned long)vq->avail,
362
        .used_user_addr = (uint64_t)(unsigned long)vq->used,
363
        .log_guest_addr = vq->used_phys,
364
        .flags = enable_log ? (1 << VHOST_VRING_F_LOG) : 0,
365
    };
366
    int r = ioctl(dev->control, VHOST_SET_VRING_ADDR, &addr);
367
    if (r < 0) {
368
        return -errno;
369
    }
370
    return 0;
371
}
372

    
373
static int vhost_dev_set_features(struct vhost_dev *dev, bool enable_log)
374
{
375
    uint64_t features = dev->acked_features;
376
    int r;
377
    if (enable_log) {
378
        features |= 0x1 << VHOST_F_LOG_ALL;
379
    }
380
    r = ioctl(dev->control, VHOST_SET_FEATURES, &features);
381
    return r < 0 ? -errno : 0;
382
}
383

    
384
static int vhost_dev_set_log(struct vhost_dev *dev, bool enable_log)
385
{
386
    int r, t, i;
387
    r = vhost_dev_set_features(dev, enable_log);
388
    if (r < 0) {
389
        goto err_features;
390
    }
391
    for (i = 0; i < dev->nvqs; ++i) {
392
        r = vhost_virtqueue_set_addr(dev, dev->vqs + i, i,
393
                                     enable_log);
394
        if (r < 0) {
395
            goto err_vq;
396
        }
397
    }
398
    return 0;
399
err_vq:
400
    for (; i >= 0; --i) {
401
        t = vhost_virtqueue_set_addr(dev, dev->vqs + i, i,
402
                                     dev->log_enabled);
403
        assert(t >= 0);
404
    }
405
    t = vhost_dev_set_features(dev, dev->log_enabled);
406
    assert(t >= 0);
407
err_features:
408
    return r;
409
}
410

    
411
static int vhost_client_migration_log(CPUPhysMemoryClient *client,
412
                                      int enable)
413
{
414
    struct vhost_dev *dev = container_of(client, struct vhost_dev, client);
415
    int r;
416
    if (!!enable == dev->log_enabled) {
417
        return 0;
418
    }
419
    if (!dev->started) {
420
        dev->log_enabled = enable;
421
        return 0;
422
    }
423
    if (!enable) {
424
        r = vhost_dev_set_log(dev, false);
425
        if (r < 0) {
426
            return r;
427
        }
428
        if (dev->log) {
429
            qemu_free(dev->log);
430
        }
431
        dev->log = NULL;
432
        dev->log_size = 0;
433
    } else {
434
        vhost_dev_log_resize(dev, vhost_get_log_size(dev));
435
        r = vhost_dev_set_log(dev, true);
436
        if (r < 0) {
437
            return r;
438
        }
439
    }
440
    dev->log_enabled = enable;
441
    return 0;
442
}
443

    
444
static int vhost_virtqueue_init(struct vhost_dev *dev,
445
                                struct VirtIODevice *vdev,
446
                                struct vhost_virtqueue *vq,
447
                                unsigned idx)
448
{
449
    target_phys_addr_t s, l, a;
450
    int r;
451
    struct vhost_vring_file file = {
452
        .index = idx,
453
    };
454
    struct vhost_vring_state state = {
455
        .index = idx,
456
    };
457
    struct VirtQueue *vvq = virtio_get_queue(vdev, idx);
458

    
459
    if (!vdev->binding->set_guest_notifier) {
460
        fprintf(stderr, "binding does not support guest notifiers\n");
461
        return -ENOSYS;
462
    }
463

    
464
    if (!vdev->binding->set_host_notifier) {
465
        fprintf(stderr, "binding does not support host notifiers\n");
466
        return -ENOSYS;
467
    }
468

    
469
    vq->num = state.num = virtio_queue_get_num(vdev, idx);
470
    r = ioctl(dev->control, VHOST_SET_VRING_NUM, &state);
471
    if (r) {
472
        return -errno;
473
    }
474

    
475
    state.num = virtio_queue_get_last_avail_idx(vdev, idx);
476
    r = ioctl(dev->control, VHOST_SET_VRING_BASE, &state);
477
    if (r) {
478
        return -errno;
479
    }
480

    
481
    s = l = virtio_queue_get_desc_size(vdev, idx);
482
    a = virtio_queue_get_desc_addr(vdev, idx);
483
    vq->desc = cpu_physical_memory_map(a, &l, 0);
484
    if (!vq->desc || l != s) {
485
        r = -ENOMEM;
486
        goto fail_alloc_desc;
487
    }
488
    s = l = virtio_queue_get_avail_size(vdev, idx);
489
    a = virtio_queue_get_avail_addr(vdev, idx);
490
    vq->avail = cpu_physical_memory_map(a, &l, 0);
491
    if (!vq->avail || l != s) {
492
        r = -ENOMEM;
493
        goto fail_alloc_avail;
494
    }
495
    vq->used_size = s = l = virtio_queue_get_used_size(vdev, idx);
496
    vq->used_phys = a = virtio_queue_get_used_addr(vdev, idx);
497
    vq->used = cpu_physical_memory_map(a, &l, 1);
498
    if (!vq->used || l != s) {
499
        r = -ENOMEM;
500
        goto fail_alloc_used;
501
    }
502

    
503
    vq->ring_size = s = l = virtio_queue_get_ring_size(vdev, idx);
504
    vq->ring_phys = a = virtio_queue_get_ring_addr(vdev, idx);
505
    vq->ring = cpu_physical_memory_map(a, &l, 1);
506
    if (!vq->ring || l != s) {
507
        r = -ENOMEM;
508
        goto fail_alloc_ring;
509
    }
510

    
511
    r = vhost_virtqueue_set_addr(dev, vq, idx, dev->log_enabled);
512
    if (r < 0) {
513
        r = -errno;
514
        goto fail_alloc;
515
    }
516
    r = vdev->binding->set_guest_notifier(vdev->binding_opaque, idx, true);
517
    if (r < 0) {
518
        fprintf(stderr, "Error binding guest notifier: %d\n", -r);
519
        goto fail_guest_notifier;
520
    }
521

    
522
    r = vdev->binding->set_host_notifier(vdev->binding_opaque, idx, true);
523
    if (r < 0) {
524
        fprintf(stderr, "Error binding host notifier: %d\n", -r);
525
        goto fail_host_notifier;
526
    }
527

    
528
    file.fd = event_notifier_get_fd(virtio_queue_get_host_notifier(vvq));
529
    r = ioctl(dev->control, VHOST_SET_VRING_KICK, &file);
530
    if (r) {
531
        goto fail_kick;
532
    }
533

    
534
    file.fd = event_notifier_get_fd(virtio_queue_get_guest_notifier(vvq));
535
    r = ioctl(dev->control, VHOST_SET_VRING_CALL, &file);
536
    if (r) {
537
        goto fail_call;
538
    }
539

    
540
    return 0;
541

    
542
fail_call:
543
fail_kick:
544
    vdev->binding->set_host_notifier(vdev->binding_opaque, idx, false);
545
fail_host_notifier:
546
    vdev->binding->set_guest_notifier(vdev->binding_opaque, idx, false);
547
fail_guest_notifier:
548
fail_alloc:
549
    cpu_physical_memory_unmap(vq->ring, virtio_queue_get_ring_size(vdev, idx),
550
                              0, 0);
551
fail_alloc_ring:
552
    cpu_physical_memory_unmap(vq->used, virtio_queue_get_used_size(vdev, idx),
553
                              0, 0);
554
fail_alloc_used:
555
    cpu_physical_memory_unmap(vq->avail, virtio_queue_get_avail_size(vdev, idx),
556
                              0, 0);
557
fail_alloc_avail:
558
    cpu_physical_memory_unmap(vq->desc, virtio_queue_get_desc_size(vdev, idx),
559
                              0, 0);
560
fail_alloc_desc:
561
    return r;
562
}
563

    
564
static void vhost_virtqueue_cleanup(struct vhost_dev *dev,
565
                                    struct VirtIODevice *vdev,
566
                                    struct vhost_virtqueue *vq,
567
                                    unsigned idx)
568
{
569
    struct vhost_vring_state state = {
570
        .index = idx,
571
    };
572
    int r;
573
    r = vdev->binding->set_guest_notifier(vdev->binding_opaque, idx, false);
574
    if (r < 0) {
575
        fprintf(stderr, "vhost VQ %d guest cleanup failed: %d\n", idx, r);
576
        fflush(stderr);
577
    }
578
    assert (r >= 0);
579

    
580
    r = vdev->binding->set_host_notifier(vdev->binding_opaque, idx, false);
581
    if (r < 0) {
582
        fprintf(stderr, "vhost VQ %d host cleanup failed: %d\n", idx, r);
583
        fflush(stderr);
584
    }
585
    assert (r >= 0);
586
    r = ioctl(dev->control, VHOST_GET_VRING_BASE, &state);
587
    if (r < 0) {
588
        fprintf(stderr, "vhost VQ %d ring restore failed: %d\n", idx, r);
589
        fflush(stderr);
590
    }
591
    virtio_queue_set_last_avail_idx(vdev, idx, state.num);
592
    assert (r >= 0);
593
    cpu_physical_memory_unmap(vq->ring, virtio_queue_get_ring_size(vdev, idx),
594
                              0, virtio_queue_get_ring_size(vdev, idx));
595
    cpu_physical_memory_unmap(vq->used, virtio_queue_get_used_size(vdev, idx),
596
                              1, virtio_queue_get_used_size(vdev, idx));
597
    cpu_physical_memory_unmap(vq->avail, virtio_queue_get_avail_size(vdev, idx),
598
                              0, virtio_queue_get_avail_size(vdev, idx));
599
    cpu_physical_memory_unmap(vq->desc, virtio_queue_get_desc_size(vdev, idx),
600
                              0, virtio_queue_get_desc_size(vdev, idx));
601
}
602

    
603
int vhost_dev_init(struct vhost_dev *hdev, int devfd)
604
{
605
    uint64_t features;
606
    int r;
607
    if (devfd >= 0) {
608
        hdev->control = devfd;
609
    } else {
610
        hdev->control = open("/dev/vhost-net", O_RDWR);
611
        if (hdev->control < 0) {
612
            return -errno;
613
        }
614
    }
615
    r = ioctl(hdev->control, VHOST_SET_OWNER, NULL);
616
    if (r < 0) {
617
        goto fail;
618
    }
619

    
620
    r = ioctl(hdev->control, VHOST_GET_FEATURES, &features);
621
    if (r < 0) {
622
        goto fail;
623
    }
624
    hdev->features = features;
625

    
626
    hdev->client.set_memory = vhost_client_set_memory;
627
    hdev->client.sync_dirty_bitmap = vhost_client_sync_dirty_bitmap;
628
    hdev->client.migration_log = vhost_client_migration_log;
629
    hdev->mem = qemu_mallocz(offsetof(struct vhost_memory, regions));
630
    hdev->log = NULL;
631
    hdev->log_size = 0;
632
    hdev->log_enabled = false;
633
    hdev->started = false;
634
    cpu_register_phys_memory_client(&hdev->client);
635
    return 0;
636
fail:
637
    r = -errno;
638
    close(hdev->control);
639
    return r;
640
}
641

    
642
void vhost_dev_cleanup(struct vhost_dev *hdev)
643
{
644
    cpu_unregister_phys_memory_client(&hdev->client);
645
    qemu_free(hdev->mem);
646
    close(hdev->control);
647
}
648

    
649
int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev)
650
{
651
    int i, r;
652

    
653
    r = vhost_dev_set_features(hdev, hdev->log_enabled);
654
    if (r < 0) {
655
        goto fail;
656
    }
657
    r = ioctl(hdev->control, VHOST_SET_MEM_TABLE, hdev->mem);
658
    if (r < 0) {
659
        r = -errno;
660
        goto fail;
661
    }
662
    for (i = 0; i < hdev->nvqs; ++i) {
663
        r = vhost_virtqueue_init(hdev,
664
                                 vdev,
665
                                 hdev->vqs + i,
666
                                 i);
667
        if (r < 0) {
668
            goto fail_vq;
669
        }
670
    }
671

    
672
    if (hdev->log_enabled) {
673
        hdev->log_size = vhost_get_log_size(hdev);
674
        hdev->log = hdev->log_size ?
675
            qemu_mallocz(hdev->log_size * sizeof *hdev->log) : NULL;
676
        r = ioctl(hdev->control, VHOST_SET_LOG_BASE,
677
                  (uint64_t)(unsigned long)hdev->log);
678
        if (r < 0) {
679
            r = -errno;
680
            goto fail_vq;
681
        }
682
    }
683

    
684
    hdev->started = true;
685

    
686
    return 0;
687
fail_vq:
688
    while (--i >= 0) {
689
        vhost_virtqueue_cleanup(hdev,
690
                                vdev,
691
                                hdev->vqs + i,
692
                                i);
693
    }
694
fail:
695
    return r;
696
}
697

    
698
void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev)
699
{
700
    int i;
701
    for (i = 0; i < hdev->nvqs; ++i) {
702
        vhost_virtqueue_cleanup(hdev,
703
                                vdev,
704
                                hdev->vqs + i,
705
                                i);
706
    }
707
    vhost_client_sync_dirty_bitmap(&hdev->client, 0,
708
                                   (target_phys_addr_t)~0x0ull);
709
    hdev->started = false;
710
    qemu_free(hdev->log);
711
    hdev->log_size = 0;
712
}