aboutsummaryrefslogtreecommitdiff
path: root/hw/xen/xen-hvm-common.c
blob: 565dc39c8f622c05db37eea40f4391dc640d6ff6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
#include "qemu/osdep.h"
#include "qemu/units.h"
#include "qapi/error.h"
#include "trace.h"

#include "hw/pci/pci_host.h"
#include "hw/xen/xen-hvm-common.h"
#include "hw/xen/xen-bus.h"
#include "hw/boards.h"
#include "hw/xen/arch_hvm.h"

MemoryRegion ram_memory;

void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size, MemoryRegion *mr,
                   Error **errp)
{
    unsigned long nr_pfn;
    xen_pfn_t *pfn_list;
    int i;

    if (runstate_check(RUN_STATE_INMIGRATE)) {
        /* RAM already populated in Xen */
        fprintf(stderr, "%s: do not alloc "RAM_ADDR_FMT
                " bytes of ram at "RAM_ADDR_FMT" when runstate is INMIGRATE\n",
                __func__, size, ram_addr);
        return;
    }

    if (mr == &ram_memory) {
        return;
    }

    trace_xen_ram_alloc(ram_addr, size);

    nr_pfn = size >> TARGET_PAGE_BITS;
    pfn_list = g_new(xen_pfn_t, nr_pfn);

    for (i = 0; i < nr_pfn; i++) {
        pfn_list[i] = (ram_addr >> TARGET_PAGE_BITS) + i;
    }

    if (xc_domain_populate_physmap_exact(xen_xc, xen_domid, nr_pfn, 0, 0, pfn_list)) {
        error_setg(errp, "xen: failed to populate ram at " RAM_ADDR_FMT,
                   ram_addr);
    }

    g_free(pfn_list);
}

static void xen_set_memory(struct MemoryListener *listener,
                           MemoryRegionSection *section,
                           bool add)
{
    XenIOState *state = container_of(listener, XenIOState, memory_listener);

    if (section->mr == &ram_memory) {
        return;
    } else {
        if (add) {
            xen_map_memory_section(xen_domid, state->ioservid,
                                   section);
        } else {
            xen_unmap_memory_section(xen_domid, state->ioservid,
                                     section);
        }
    }

    arch_xen_set_memory(state, section, add);
}

void xen_region_add(MemoryListener *listener,
                           MemoryRegionSection *section)
{
    memory_region_ref(section->mr);
    xen_set_memory(listener, section, true);
}

void xen_region_del(MemoryListener *listener,
                           MemoryRegionSection *section)
{
    xen_set_memory(listener, section, false);
    memory_region_unref(section->mr);
}

void xen_io_add(MemoryListener *listener,
                       MemoryRegionSection *section)
{
    XenIOState *state = container_of(listener, XenIOState, io_listener);
    MemoryRegion *mr = section->mr;

    if (mr->ops == &unassigned_io_ops) {
        return;
    }

    memory_region_ref(mr);

    xen_map_io_section(xen_domid, state->ioservid, section);
}

void xen_io_del(MemoryListener *listener,
                       MemoryRegionSection *section)
{
    XenIOState *state = container_of(listener, XenIOState, io_listener);
    MemoryRegion *mr = section->mr;

    if (mr->ops == &unassigned_io_ops) {
        return;
    }

    xen_unmap_io_section(xen_domid, state->ioservid, section);

    memory_region_unref(mr);
}

void xen_device_realize(DeviceListener *listener,
                               DeviceState *dev)
{
    XenIOState *state = container_of(listener, XenIOState, device_listener);

    if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {
        PCIDevice *pci_dev = PCI_DEVICE(dev);
        XenPciDevice *xendev = g_new(XenPciDevice, 1);

        xendev->pci_dev = pci_dev;
        xendev->sbdf = PCI_BUILD_BDF(pci_dev_bus_num(pci_dev),
                                     pci_dev->devfn);
        QLIST_INSERT_HEAD(&state->dev_list, xendev, entry);

        xen_map_pcidev(xen_domid, state->ioservid, pci_dev);
    }
}

void xen_device_unrealize(DeviceListener *listener,
                                 DeviceState *dev)
{
    XenIOState *state = container_of(listener, XenIOState, device_listener);

    if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {
        PCIDevice *pci_dev = PCI_DEVICE(dev);
        XenPciDevice *xendev, *next;

        xen_unmap_pcidev(xen_domid, state->ioservid, pci_dev);

        QLIST_FOREACH_SAFE(xendev, &state->dev_list, entry, next) {
            if (xendev->pci_dev == pci_dev) {
                QLIST_REMOVE(xendev, entry);
                g_free(xendev);
                break;
            }
        }
    }
}

MemoryListener xen_io_listener = {
    .name = "xen-io",
    .region_add = xen_io_add,
    .region_del = xen_io_del,
    .priority = MEMORY_LISTENER_PRIORITY_ACCEL,
};

DeviceListener xen_device_listener = {
    .realize = xen_device_realize,
    .unrealize = xen_device_unrealize,
};

/* get the ioreq packets from share mem */
static ioreq_t *cpu_get_ioreq_from_shared_memory(XenIOState *state, int vcpu)
{
    ioreq_t *req = xen_vcpu_ioreq(state->shared_page, vcpu);

    if (req->state != STATE_IOREQ_READY) {
        DPRINTF("I/O request not ready: "
                "%x, ptr: %x, port: %"PRIx64", "
                "data: %"PRIx64", count: %u, size: %u\n",
                req->state, req->data_is_ptr, req->addr,
                req->data, req->count, req->size);
        return NULL;
    }

    xen_rmb(); /* see IOREQ_READY /then/ read contents of ioreq */

    req->state = STATE_IOREQ_INPROCESS;
    return req;
}

/* use poll to get the port notification */
/* ioreq_vec--out,the */
/* retval--the number of ioreq packet */
static ioreq_t *cpu_get_ioreq(XenIOState *state)
{
    MachineState *ms = MACHINE(qdev_get_machine());
    unsigned int max_cpus = ms->smp.max_cpus;
    int i;
    evtchn_port_t port;

    port = qemu_xen_evtchn_pending(state->xce_handle);
    if (port == state->bufioreq_local_port) {
        timer_mod(state->buffered_io_timer,
                BUFFER_IO_MAX_DELAY + qemu_clock_get_ms(QEMU_CLOCK_REALTIME));
        return NULL;
    }

    if (port != -1) {
        for (i = 0; i < max_cpus; i++) {
            if (state->ioreq_local_port[i] == port) {
                break;
            }
        }

        if (i == max_cpus) {
            hw_error("Fatal error while trying to get io event!\n");
        }

        /* unmask the wanted port again */
        qemu_xen_evtchn_unmask(state->xce_handle, port);

        /* get the io packet from shared memory */
        state->send_vcpu = i;
        return cpu_get_ioreq_from_shared_memory(state, i);
    }

    /* read error or read nothing */
    return NULL;
}

static uint32_t do_inp(uint32_t addr, unsigned long size)
{
    switch (size) {
        case 1:
            return cpu_inb(addr);
        case 2:
            return cpu_inw(addr);
        case 4:
            return cpu_inl(addr);
        default:
            hw_error("inp: bad size: %04x %lx", addr, size);
    }
}

static void do_outp(uint32_t addr,
        unsigned long size, uint32_t val)
{
    switch (size) {
        case 1:
            return cpu_outb(addr, val);
        case 2:
            return cpu_outw(addr, val);
        case 4:
            return cpu_outl(addr, val);
        default:
            hw_error("outp: bad size: %04x %lx", addr, size);
    }
}

/*
 * Helper functions which read/write an object from/to physical guest
 * memory, as part of the implementation of an ioreq.
 *
 * Equivalent to
 *   cpu_physical_memory_rw(addr + (req->df ? -1 : +1) * req->size * i,
 *                          val, req->size, 0/1)
 * except without the integer overflow problems.
 */
static void rw_phys_req_item(hwaddr addr,
                             ioreq_t *req, uint32_t i, void *val, int rw)
{
    /* Do everything unsigned so overflow just results in a truncated result
     * and accesses to undesired parts of guest memory, which is up
     * to the guest */
    hwaddr offset = (hwaddr)req->size * i;
    if (req->df) {
        addr -= offset;
    } else {
        addr += offset;
    }
    cpu_physical_memory_rw(addr, val, req->size, rw);
}

static inline void read_phys_req_item(hwaddr addr,
                                      ioreq_t *req, uint32_t i, void *val)
{
    rw_phys_req_item(addr, req, i, val, 0);
}
static inline void write_phys_req_item(hwaddr addr,
                                       ioreq_t *req, uint32_t i, void *val)
{
    rw_phys_req_item(addr, req, i, val, 1);
}


void cpu_ioreq_pio(ioreq_t *req)
{
    uint32_t i;

    trace_cpu_ioreq_pio(req, req->dir, req->df, req->data_is_ptr, req->addr,
                         req->data, req->count, req->size);

    if (req->size > sizeof(uint32_t)) {
        hw_error("PIO: bad size (%u)", req->size);
    }

    if (req->dir == IOREQ_READ) {
        if (!req->data_is_ptr) {
            req->data = do_inp(req->addr, req->size);
            trace_cpu_ioreq_pio_read_reg(req, req->data, req->addr,
                                         req->size);
        } else {
            uint32_t tmp;

            for (i = 0; i < req->count; i++) {
                tmp = do_inp(req->addr, req->size);
                write_phys_req_item(req->data, req, i, &tmp);
            }
        }
    } else if (req->dir == IOREQ_WRITE) {
        if (!req->data_is_ptr) {
            trace_cpu_ioreq_pio_write_reg(req, req->data, req->addr,
                                          req->size);
            do_outp(req->addr, req->size, req->data);
        } else {
            for (i = 0; i < req->count; i++) {
                uint32_t tmp = 0;

                read_phys_req_item(req->data, req, i, &tmp);
                do_outp(req->addr, req->size, tmp);
            }
        }
    }
}

static void cpu_ioreq_move(ioreq_t *req)
{
    uint32_t i;

    trace_cpu_ioreq_move(req, req->dir, req->df, req->data_is_ptr, req->addr,
                         req->data, req->count, req->size);

    if (req->size > sizeof(req->data)) {
        hw_error("MMIO: bad size (%u)", req->size);
    }

    if (!req->data_is_ptr) {
        if (req->dir == IOREQ_READ) {
            for (i = 0; i < req->count; i++) {
                read_phys_req_item(req->addr, req, i, &req->data);
            }
        } else if (req->dir == IOREQ_WRITE) {
            for (i = 0; i < req->count; i++) {
                write_phys_req_item(req->addr, req, i, &req->data);
            }
        }
    } else {
        uint64_t tmp;

        if (req->dir == IOREQ_READ) {
            for (i = 0; i < req->count; i++) {
                read_phys_req_item(req->addr, req, i, &tmp);
                write_phys_req_item(req->data, req, i, &tmp);
            }
        } else if (req->dir == IOREQ_WRITE) {
            for (i = 0; i < req->count; i++) {
                read_phys_req_item(req->data, req, i, &tmp);
                write_phys_req_item(req->addr, req, i, &tmp);
            }
        }
    }
}

static void cpu_ioreq_config(XenIOState *state, ioreq_t *req)
{
    uint32_t sbdf = req->addr >> 32;
    uint32_t reg = req->addr;
    XenPciDevice *xendev;

    if (req->size != sizeof(uint8_t) && req->size != sizeof(uint16_t) &&
        req->size != sizeof(uint32_t)) {
        hw_error("PCI config access: bad size (%u)", req->size);
    }

    if (req->count != 1) {
        hw_error("PCI config access: bad count (%u)", req->count);
    }

    QLIST_FOREACH(xendev, &state->dev_list, entry) {
        if (xendev->sbdf != sbdf) {
            continue;
        }

        if (!req->data_is_ptr) {
            if (req->dir == IOREQ_READ) {
                req->data = pci_host_config_read_common(
                    xendev->pci_dev, reg, PCI_CONFIG_SPACE_SIZE,
                    req->size);
                trace_cpu_ioreq_config_read(req, xendev->sbdf, reg,
                                            req->size, req->data);
            } else if (req->dir == IOREQ_WRITE) {
                trace_cpu_ioreq_config_write(req, xendev->sbdf, reg,
                                             req->size, req->data);
                pci_host_config_write_common(
                    xendev->pci_dev, reg, PCI_CONFIG_SPACE_SIZE,
                    req->data, req->size);
            }
        } else {
            uint32_t tmp;

            if (req->dir == IOREQ_READ) {
                tmp = pci_host_config_read_common(
                    xendev->pci_dev, reg, PCI_CONFIG_SPACE_SIZE,
                    req->size);
                trace_cpu_ioreq_config_read(req, xendev->sbdf, reg,
                                            req->size, tmp);
                write_phys_req_item(req->data, req, 0, &tmp);
            } else if (req->dir == IOREQ_WRITE) {
                read_phys_req_item(req->data, req, 0, &tmp);
                trace_cpu_ioreq_config_write(req, xendev->sbdf, reg,
                                             req->size, tmp);
                pci_host_config_write_common(
                    xendev->pci_dev, reg, PCI_CONFIG_SPACE_SIZE,
                    tmp, req->size);
            }
        }
    }
}

static void handle_ioreq(XenIOState *state, ioreq_t *req)
{
    trace_handle_ioreq(req, req->type, req->dir, req->df, req->data_is_ptr,
                       req->addr, req->data, req->count, req->size);

    if (!req->data_is_ptr && (req->dir == IOREQ_WRITE) &&
            (req->size < sizeof (target_ulong))) {
        req->data &= ((target_ulong) 1 << (8 * req->size)) - 1;
    }

    if (req->dir == IOREQ_WRITE)
        trace_handle_ioreq_write(req, req->type, req->df, req->data_is_ptr,
                                 req->addr, req->data, req->count, req->size);

    switch (req->type) {
        case IOREQ_TYPE_PIO:
            cpu_ioreq_pio(req);
            break;
        case IOREQ_TYPE_COPY:
            cpu_ioreq_move(req);
            break;
        case IOREQ_TYPE_TIMEOFFSET:
            break;
        case IOREQ_TYPE_INVALIDATE:
            xen_invalidate_map_cache();
            break;
        case IOREQ_TYPE_PCI_CONFIG:
            cpu_ioreq_config(state, req);
            break;
        default:
            arch_handle_ioreq(state, req);
    }
    if (req->dir == IOREQ_READ) {
        trace_handle_ioreq_read(req, req->type, req->df, req->data_is_ptr,
                                req->addr, req->data, req->count, req->size);
    }
}

static bool handle_buffered_iopage(XenIOState *state)
{
    buffered_iopage_t *buf_page = state->buffered_io_page;
    buf_ioreq_t *buf_req = NULL;
    bool handled_ioreq = false;
    ioreq_t req;
    int qw;

    if (!buf_page) {
        return 0;
    }

    memset(&req, 0x00, sizeof(req));
    req.state = STATE_IOREQ_READY;
    req.count = 1;
    req.dir = IOREQ_WRITE;

    for (;;) {
        uint32_t rdptr = buf_page->read_pointer, wrptr;

        xen_rmb();
        wrptr = buf_page->write_pointer;
        xen_rmb();
        if (rdptr != buf_page->read_pointer) {
            continue;
        }
        if (rdptr == wrptr) {
            break;
        }
        buf_req = &buf_page->buf_ioreq[rdptr % IOREQ_BUFFER_SLOT_NUM];
        req.size = 1U << buf_req->size;
        req.addr = buf_req->addr;
        req.data = buf_req->data;
        req.type = buf_req->type;
        xen_rmb();
        qw = (req.size == 8);
        if (qw) {
            if (rdptr + 1 == wrptr) {
                hw_error("Incomplete quad word buffered ioreq");
            }
            buf_req = &buf_page->buf_ioreq[(rdptr + 1) %
                                           IOREQ_BUFFER_SLOT_NUM];
            req.data |= ((uint64_t)buf_req->data) << 32;
            xen_rmb();
        }

        handle_ioreq(state, &req);

        /* Only req.data may get updated by handle_ioreq(), albeit even that
         * should not happen as such data would never make it to the guest (we
         * can only usefully see writes here after all).
         */
        assert(req.state == STATE_IOREQ_READY);
        assert(req.count == 1);
        assert(req.dir == IOREQ_WRITE);
        assert(!req.data_is_ptr);

        qatomic_add(&buf_page->read_pointer, qw + 1);
        handled_ioreq = true;
    }

    return handled_ioreq;
}

static void handle_buffered_io(void *opaque)
{
    XenIOState *state = opaque;

    if (handle_buffered_iopage(state)) {
        timer_mod(state->buffered_io_timer,
                BUFFER_IO_MAX_DELAY + qemu_clock_get_ms(QEMU_CLOCK_REALTIME));
    } else {
        timer_del(state->buffered_io_timer);
        qemu_xen_evtchn_unmask(state->xce_handle, state->bufioreq_local_port);
    }
}

static void cpu_handle_ioreq(void *opaque)
{
    XenIOState *state = opaque;
    ioreq_t *req = cpu_get_ioreq(state);

    handle_buffered_iopage(state);
    if (req) {
        ioreq_t copy = *req;

        xen_rmb();
        handle_ioreq(state, &copy);
        req->data = copy.data;

        if (req->state != STATE_IOREQ_INPROCESS) {
            fprintf(stderr, "Badness in I/O request ... not in service?!: "
                    "%x, ptr: %x, port: %"PRIx64", "
                    "data: %"PRIx64", count: %u, size: %u, type: %u\n",
                    req->state, req->data_is_ptr, req->addr,
                    req->data, req->count, req->size, req->type);
            destroy_hvm_domain(false);
            return;
        }

        xen_wmb(); /* Update ioreq contents /then/ update state. */

        /*
         * We do this before we send the response so that the tools
         * have the opportunity to pick up on the reset before the
         * guest resumes and does a hlt with interrupts disabled which
         * causes Xen to powerdown the domain.
         */
        if (runstate_is_running()) {
            ShutdownCause request;

            if (qemu_shutdown_requested_get()) {
                destroy_hvm_domain(false);
            }
            request = qemu_reset_requested_get();
            if (request) {
                qemu_system_reset(request);
                destroy_hvm_domain(true);
            }
        }

        req->state = STATE_IORESP_READY;
        qemu_xen_evtchn_notify(state->xce_handle,
                               state->ioreq_local_port[state->send_vcpu]);
    }
}

static void xen_main_loop_prepare(XenIOState *state)
{
    int evtchn_fd = -1;

    if (state->xce_handle != NULL) {
        evtchn_fd = qemu_xen_evtchn_fd(state->xce_handle);
    }

    state->buffered_io_timer = timer_new_ms(QEMU_CLOCK_REALTIME, handle_buffered_io,
                                                 state);

    if (evtchn_fd != -1) {
        CPUState *cpu_state;

        DPRINTF("%s: Init cpu_by_vcpu_id\n", __func__);
        CPU_FOREACH(cpu_state) {
            DPRINTF("%s: cpu_by_vcpu_id[%d]=%p\n",
                    __func__, cpu_state->cpu_index, cpu_state);
            state->cpu_by_vcpu_id[cpu_state->cpu_index] = cpu_state;
        }
        qemu_set_fd_handler(evtchn_fd, cpu_handle_ioreq, NULL, state);
    }
}


void xen_hvm_change_state_handler(void *opaque, bool running,
                                         RunState rstate)
{
    XenIOState *state = opaque;

    if (running) {
        xen_main_loop_prepare(state);
    }

    xen_set_ioreq_server_state(xen_domid,
                               state->ioservid,
                               (rstate == RUN_STATE_RUNNING));
}

void xen_exit_notifier(Notifier *n, void *data)
{
    XenIOState *state = container_of(n, XenIOState, exit);

    xen_destroy_ioreq_server(xen_domid, state->ioservid);
    if (state->fres != NULL) {
        xenforeignmemory_unmap_resource(xen_fmem, state->fres);
    }

    qemu_xen_evtchn_close(state->xce_handle);
    xs_daemon_close(state->xenstore);
}

static int xen_map_ioreq_server(XenIOState *state)
{
    void *addr = NULL;
    xen_pfn_t ioreq_pfn;
    xen_pfn_t bufioreq_pfn;
    evtchn_port_t bufioreq_evtchn;
    int rc;

    /*
     * Attempt to map using the resource API and fall back to normal
     * foreign mapping if this is not supported.
     */
    QEMU_BUILD_BUG_ON(XENMEM_resource_ioreq_server_frame_bufioreq != 0);
    QEMU_BUILD_BUG_ON(XENMEM_resource_ioreq_server_frame_ioreq(0) != 1);
    state->fres = xenforeignmemory_map_resource(xen_fmem, xen_domid,
                                         XENMEM_resource_ioreq_server,
                                         state->ioservid, 0, 2,
                                         &addr,
                                         PROT_READ | PROT_WRITE, 0);
    if (state->fres != NULL) {
        trace_xen_map_resource_ioreq(state->ioservid, addr);
        state->buffered_io_page = addr;
        state->shared_page = addr + XC_PAGE_SIZE;
    } else if (errno != EOPNOTSUPP) {
        error_report("failed to map ioreq server resources: error %d handle=%p",
                     errno, xen_xc);
        return -1;
    }

    rc = xen_get_ioreq_server_info(xen_domid, state->ioservid,
                                   (state->shared_page == NULL) ?
                                   &ioreq_pfn : NULL,
                                   (state->buffered_io_page == NULL) ?
                                   &bufioreq_pfn : NULL,
                                   &bufioreq_evtchn);
    if (rc < 0) {
        error_report("failed to get ioreq server info: error %d handle=%p",
                     errno, xen_xc);
        return rc;
    }

    if (state->shared_page == NULL) {
        DPRINTF("shared page at pfn %lx\n", ioreq_pfn);

        state->shared_page = xenforeignmemory_map(xen_fmem, xen_domid,
                                                  PROT_READ | PROT_WRITE,
                                                  1, &ioreq_pfn, NULL);
        if (state->shared_page == NULL) {
            error_report("map shared IO page returned error %d handle=%p",
                         errno, xen_xc);
        }
    }

    if (state->buffered_io_page == NULL) {
        DPRINTF("buffered io page at pfn %lx\n", bufioreq_pfn);

        state->buffered_io_page = xenforeignmemory_map(xen_fmem, xen_domid,
                                                       PROT_READ | PROT_WRITE,
                                                       1, &bufioreq_pfn,
                                                       NULL);
        if (state->buffered_io_page == NULL) {
            error_report("map buffered IO page returned error %d", errno);
            return -1;
        }
    }

    if (state->shared_page == NULL || state->buffered_io_page == NULL) {
        return -1;
    }

    DPRINTF("buffered io evtchn is %x\n", bufioreq_evtchn);

    state->bufioreq_remote_port = bufioreq_evtchn;

    return 0;
}

void destroy_hvm_domain(bool reboot)
{
    xc_interface *xc_handle;
    int sts;
    int rc;

    unsigned int reason = reboot ? SHUTDOWN_reboot : SHUTDOWN_poweroff;

    if (xen_dmod) {
        rc = xendevicemodel_shutdown(xen_dmod, xen_domid, reason);
        if (!rc) {
            return;
        }
        if (errno != ENOTTY /* old Xen */) {
            error_report("xendevicemodel_shutdown failed with error %d", errno);
        }
        /* well, try the old thing then */
    }

    xc_handle = xc_interface_open(0, 0, 0);
    if (xc_handle == NULL) {
        fprintf(stderr, "Cannot acquire xenctrl handle\n");
    } else {
        sts = xc_domain_shutdown(xc_handle, xen_domid, reason);
        if (sts != 0) {
            fprintf(stderr, "xc_domain_shutdown failed to issue %s, "
                    "sts %d, %s\n", reboot ? "reboot" : "poweroff",
                    sts, strerror(errno));
        } else {
            fprintf(stderr, "Issued domain %d %s\n", xen_domid,
                    reboot ? "reboot" : "poweroff");
        }
        xc_interface_close(xc_handle);
    }
}

void xen_shutdown_fatal_error(const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    vfprintf(stderr, fmt, ap);
    va_end(ap);
    fprintf(stderr, "Will destroy the domain.\n");
    /* destroy the domain */
    qemu_system_shutdown_request(SHUTDOWN_CAUSE_HOST_ERROR);
}

static void xen_do_ioreq_register(XenIOState *state,
                                  unsigned int max_cpus,
                                  const MemoryListener *xen_memory_listener)
{
    int i, rc;

    state->exit.notify = xen_exit_notifier;
    qemu_add_exit_notifier(&state->exit);

    /*
     * Register wake-up support in QMP query-current-machine API
     */
    qemu_register_wakeup_support();

    rc = xen_map_ioreq_server(state);
    if (rc < 0) {
        goto err;
    }

    /* Note: cpus is empty at this point in init */
    state->cpu_by_vcpu_id = g_new0(CPUState *, max_cpus);

    rc = xen_set_ioreq_server_state(xen_domid, state->ioservid, true);
    if (rc < 0) {
        error_report("failed to enable ioreq server info: error %d handle=%p",
                     errno, xen_xc);
        goto err;
    }

    state->ioreq_local_port = g_new0(evtchn_port_t, max_cpus);

    /* FIXME: how about if we overflow the page here? */
    for (i = 0; i < max_cpus; i++) {
        rc = qemu_xen_evtchn_bind_interdomain(state->xce_handle, xen_domid,
                                              xen_vcpu_eport(state->shared_page,
                                                             i));
        if (rc == -1) {
            error_report("shared evtchn %d bind error %d", i, errno);
            goto err;
        }
        state->ioreq_local_port[i] = rc;
    }

    rc = qemu_xen_evtchn_bind_interdomain(state->xce_handle, xen_domid,
                                          state->bufioreq_remote_port);
    if (rc == -1) {
        error_report("buffered evtchn bind error %d", errno);
        goto err;
    }
    state->bufioreq_local_port = rc;

    /* Init RAM management */
#ifdef XEN_COMPAT_PHYSMAP
    xen_map_cache_init(xen_phys_offset_to_gaddr, state);
#else
    xen_map_cache_init(NULL, state);
#endif

    qemu_add_vm_change_state_handler(xen_hvm_change_state_handler, state);

    state->memory_listener = *xen_memory_listener;
    memory_listener_register(&state->memory_listener, &address_space_memory);

    state->io_listener = xen_io_listener;
    memory_listener_register(&state->io_listener, &address_space_io);

    state->device_listener = xen_device_listener;
    QLIST_INIT(&state->dev_list);
    device_listener_register(&state->device_listener);

    return;

err:
    error_report("xen hardware virtual machine initialisation failed");
    exit(1);
}

void xen_register_ioreq(XenIOState *state, unsigned int max_cpus,
                        const MemoryListener *xen_memory_listener)
{
    int rc;

    setup_xen_backend_ops();

    state->xce_handle = qemu_xen_evtchn_open();
    if (state->xce_handle == NULL) {
        error_report("xen: event channel open failed with error %d", errno);
        goto err;
    }

    state->xenstore = xs_daemon_open();
    if (state->xenstore == NULL) {
        error_report("xen: xenstore open failed with error %d", errno);
        goto err;
    }

    rc = xen_create_ioreq_server(xen_domid, &state->ioservid);
    if (!rc) {
        xen_do_ioreq_register(state, max_cpus, xen_memory_listener);
    } else {
        warn_report("xen: failed to create ioreq server");
    }

    xen_bus_init();

    xen_be_init();

    return;

err:
    error_report("xen hardware virtual machine backend registration failed");
    exit(1);
}