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1
/*
2
 * QEMU KVM support
3
 *
4
 * Copyright IBM, Corp. 2008
5
 *           Red Hat, Inc. 2008
6
 *
7
 * Authors:
8
 *  Anthony Liguori   <aliguori@us.ibm.com>
9
 *  Glauber Costa     <gcosta@redhat.com>
10
 *
11
 * This work is licensed under the terms of the GNU GPL, version 2 or later.
12
 * See the COPYING file in the top-level directory.
13
 *
14
 */
15

    
16
#include <sys/types.h>
17
#include <sys/ioctl.h>
18
#include <sys/mman.h>
19
#include <stdarg.h>
20

    
21
#include <linux/kvm.h>
22

    
23
#include "qemu-common.h"
24
#include "sysemu.h"
25
#include "hw/hw.h"
26
#include "gdbstub.h"
27
#include "kvm.h"
28

    
29
/* KVM uses PAGE_SIZE in it's definition of COALESCED_MMIO_MAX */
30
#define PAGE_SIZE TARGET_PAGE_SIZE
31

    
32
//#define DEBUG_KVM
33

    
34
#ifdef DEBUG_KVM
35
#define dprintf(fmt, ...) \
36
    do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
37
#else
38
#define dprintf(fmt, ...) \
39
    do { } while (0)
40
#endif
41

    
42
typedef struct KVMSlot
43
{
44
    target_phys_addr_t start_addr;
45
    ram_addr_t memory_size;
46
    ram_addr_t phys_offset;
47
    int slot;
48
    int flags;
49
} KVMSlot;
50

    
51
typedef struct kvm_dirty_log KVMDirtyLog;
52

    
53
int kvm_allowed = 0;
54

    
55
struct KVMState
56
{
57
    KVMSlot slots[32];
58
    int fd;
59
    int vmfd;
60
    int coalesced_mmio;
61
    int broken_set_mem_region;
62
    int migration_log;
63
#ifdef KVM_CAP_SET_GUEST_DEBUG
64
    struct kvm_sw_breakpoint_head kvm_sw_breakpoints;
65
#endif
66
};
67

    
68
static KVMState *kvm_state;
69

    
70
static KVMSlot *kvm_alloc_slot(KVMState *s)
71
{
72
    int i;
73

    
74
    for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
75
        /* KVM private memory slots */
76
        if (i >= 8 && i < 12)
77
            continue;
78
        if (s->slots[i].memory_size == 0)
79
            return &s->slots[i];
80
    }
81

    
82
    fprintf(stderr, "%s: no free slot available\n", __func__);
83
    abort();
84
}
85

    
86
static KVMSlot *kvm_lookup_matching_slot(KVMState *s,
87
                                         target_phys_addr_t start_addr,
88
                                         target_phys_addr_t end_addr)
89
{
90
    int i;
91

    
92
    for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
93
        KVMSlot *mem = &s->slots[i];
94

    
95
        if (start_addr == mem->start_addr &&
96
            end_addr == mem->start_addr + mem->memory_size) {
97
            return mem;
98
        }
99
    }
100

    
101
    return NULL;
102
}
103

    
104
/*
105
 * Find overlapping slot with lowest start address
106
 */
107
static KVMSlot *kvm_lookup_overlapping_slot(KVMState *s,
108
                                            target_phys_addr_t start_addr,
109
                                            target_phys_addr_t end_addr)
110
{
111
    KVMSlot *found = NULL;
112
    int i;
113

    
114
    for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
115
        KVMSlot *mem = &s->slots[i];
116

    
117
        if (mem->memory_size == 0 ||
118
            (found && found->start_addr < mem->start_addr)) {
119
            continue;
120
        }
121

    
122
        if (end_addr > mem->start_addr &&
123
            start_addr < mem->start_addr + mem->memory_size) {
124
            found = mem;
125
        }
126
    }
127

    
128
    return found;
129
}
130

    
131
static int kvm_set_user_memory_region(KVMState *s, KVMSlot *slot)
132
{
133
    struct kvm_userspace_memory_region mem;
134

    
135
    mem.slot = slot->slot;
136
    mem.guest_phys_addr = slot->start_addr;
137
    mem.memory_size = slot->memory_size;
138
    mem.userspace_addr = (unsigned long)qemu_get_ram_ptr(slot->phys_offset);
139
    mem.flags = slot->flags;
140
    if (s->migration_log) {
141
        mem.flags |= KVM_MEM_LOG_DIRTY_PAGES;
142
    }
143
    return kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, &mem);
144
}
145

    
146
static void kvm_reset_vcpu(void *opaque)
147
{
148
    CPUState *env = opaque;
149

    
150
    if (kvm_arch_put_registers(env)) {
151
        fprintf(stderr, "Fatal: kvm vcpu reset failed\n");
152
        abort();
153
    }
154
}
155

    
156
int kvm_init_vcpu(CPUState *env)
157
{
158
    KVMState *s = kvm_state;
159
    long mmap_size;
160
    int ret;
161

    
162
    dprintf("kvm_init_vcpu\n");
163

    
164
    ret = kvm_vm_ioctl(s, KVM_CREATE_VCPU, env->cpu_index);
165
    if (ret < 0) {
166
        dprintf("kvm_create_vcpu failed\n");
167
        goto err;
168
    }
169

    
170
    env->kvm_fd = ret;
171
    env->kvm_state = s;
172

    
173
    mmap_size = kvm_ioctl(s, KVM_GET_VCPU_MMAP_SIZE, 0);
174
    if (mmap_size < 0) {
175
        dprintf("KVM_GET_VCPU_MMAP_SIZE failed\n");
176
        goto err;
177
    }
178

    
179
    env->kvm_run = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED,
180
                        env->kvm_fd, 0);
181
    if (env->kvm_run == MAP_FAILED) {
182
        ret = -errno;
183
        dprintf("mmap'ing vcpu state failed\n");
184
        goto err;
185
    }
186

    
187
    ret = kvm_arch_init_vcpu(env);
188
    if (ret == 0) {
189
        qemu_register_reset(kvm_reset_vcpu, env);
190
        ret = kvm_arch_put_registers(env);
191
    }
192
err:
193
    return ret;
194
}
195

    
196
int kvm_put_mp_state(CPUState *env)
197
{
198
    struct kvm_mp_state mp_state = { .mp_state = env->mp_state };
199

    
200
    return kvm_vcpu_ioctl(env, KVM_SET_MP_STATE, &mp_state);
201
}
202

    
203
int kvm_get_mp_state(CPUState *env)
204
{
205
    struct kvm_mp_state mp_state;
206
    int ret;
207

    
208
    ret = kvm_vcpu_ioctl(env, KVM_GET_MP_STATE, &mp_state);
209
    if (ret < 0) {
210
        return ret;
211
    }
212
    env->mp_state = mp_state.mp_state;
213
    return 0;
214
}
215

    
216
/*
217
 * dirty pages logging control
218
 */
219
static int kvm_dirty_pages_log_change(target_phys_addr_t phys_addr,
220
                                      ram_addr_t size, int flags, int mask)
221
{
222
    KVMState *s = kvm_state;
223
    KVMSlot *mem = kvm_lookup_matching_slot(s, phys_addr, phys_addr + size);
224
    int old_flags;
225

    
226
    if (mem == NULL)  {
227
            fprintf(stderr, "BUG: %s: invalid parameters " TARGET_FMT_plx "-"
228
                    TARGET_FMT_plx "\n", __func__, phys_addr,
229
                    phys_addr + size - 1);
230
            return -EINVAL;
231
    }
232

    
233
    old_flags = mem->flags;
234

    
235
    flags = (mem->flags & ~mask) | flags;
236
    mem->flags = flags;
237

    
238
    /* If nothing changed effectively, no need to issue ioctl */
239
    if (s->migration_log) {
240
        flags |= KVM_MEM_LOG_DIRTY_PAGES;
241
    }
242
    if (flags == old_flags) {
243
            return 0;
244
    }
245

    
246
    return kvm_set_user_memory_region(s, mem);
247
}
248

    
249
int kvm_log_start(target_phys_addr_t phys_addr, ram_addr_t size)
250
{
251
        return kvm_dirty_pages_log_change(phys_addr, size,
252
                                          KVM_MEM_LOG_DIRTY_PAGES,
253
                                          KVM_MEM_LOG_DIRTY_PAGES);
254
}
255

    
256
int kvm_log_stop(target_phys_addr_t phys_addr, ram_addr_t size)
257
{
258
        return kvm_dirty_pages_log_change(phys_addr, size,
259
                                          0,
260
                                          KVM_MEM_LOG_DIRTY_PAGES);
261
}
262

    
263
int kvm_set_migration_log(int enable)
264
{
265
    KVMState *s = kvm_state;
266
    KVMSlot *mem;
267
    int i, err;
268

    
269
    s->migration_log = enable;
270

    
271
    for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
272
        mem = &s->slots[i];
273

    
274
        if (!!(mem->flags & KVM_MEM_LOG_DIRTY_PAGES) == enable) {
275
            continue;
276
        }
277
        err = kvm_set_user_memory_region(s, mem);
278
        if (err) {
279
            return err;
280
        }
281
    }
282
    return 0;
283
}
284

    
285
/**
286
 * kvm_physical_sync_dirty_bitmap - Grab dirty bitmap from kernel space
287
 * This function updates qemu's dirty bitmap using cpu_physical_memory_set_dirty().
288
 * This means all bits are set to dirty.
289
 *
290
 * @start_add: start of logged region.
291
 * @end_addr: end of logged region.
292
 */
293
int kvm_physical_sync_dirty_bitmap(target_phys_addr_t start_addr,
294
                                   target_phys_addr_t end_addr)
295
{
296
    KVMState *s = kvm_state;
297
    unsigned long size, allocated_size = 0;
298
    target_phys_addr_t phys_addr;
299
    ram_addr_t addr;
300
    KVMDirtyLog d;
301
    KVMSlot *mem;
302
    int ret = 0;
303

    
304
    d.dirty_bitmap = NULL;
305
    while (start_addr < end_addr) {
306
        mem = kvm_lookup_overlapping_slot(s, start_addr, end_addr);
307
        if (mem == NULL) {
308
            break;
309
        }
310

    
311
        size = ((mem->memory_size >> TARGET_PAGE_BITS) + 7) / 8;
312
        if (!d.dirty_bitmap) {
313
            d.dirty_bitmap = qemu_malloc(size);
314
        } else if (size > allocated_size) {
315
            d.dirty_bitmap = qemu_realloc(d.dirty_bitmap, size);
316
        }
317
        allocated_size = size;
318
        memset(d.dirty_bitmap, 0, allocated_size);
319

    
320
        d.slot = mem->slot;
321

    
322
        if (kvm_vm_ioctl(s, KVM_GET_DIRTY_LOG, &d) == -1) {
323
            dprintf("ioctl failed %d\n", errno);
324
            ret = -1;
325
            break;
326
        }
327

    
328
        for (phys_addr = mem->start_addr, addr = mem->phys_offset;
329
             phys_addr < mem->start_addr + mem->memory_size;
330
             phys_addr += TARGET_PAGE_SIZE, addr += TARGET_PAGE_SIZE) {
331
            unsigned long *bitmap = (unsigned long *)d.dirty_bitmap;
332
            unsigned nr = (phys_addr - mem->start_addr) >> TARGET_PAGE_BITS;
333
            unsigned word = nr / (sizeof(*bitmap) * 8);
334
            unsigned bit = nr % (sizeof(*bitmap) * 8);
335

    
336
            if ((bitmap[word] >> bit) & 1) {
337
                cpu_physical_memory_set_dirty(addr);
338
            }
339
        }
340
        start_addr = phys_addr;
341
    }
342
    qemu_free(d.dirty_bitmap);
343

    
344
    return ret;
345
}
346

    
347
int kvm_coalesce_mmio_region(target_phys_addr_t start, ram_addr_t size)
348
{
349
    int ret = -ENOSYS;
350
#ifdef KVM_CAP_COALESCED_MMIO
351
    KVMState *s = kvm_state;
352

    
353
    if (s->coalesced_mmio) {
354
        struct kvm_coalesced_mmio_zone zone;
355

    
356
        zone.addr = start;
357
        zone.size = size;
358

    
359
        ret = kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
360
    }
361
#endif
362

    
363
    return ret;
364
}
365

    
366
int kvm_uncoalesce_mmio_region(target_phys_addr_t start, ram_addr_t size)
367
{
368
    int ret = -ENOSYS;
369
#ifdef KVM_CAP_COALESCED_MMIO
370
    KVMState *s = kvm_state;
371

    
372
    if (s->coalesced_mmio) {
373
        struct kvm_coalesced_mmio_zone zone;
374

    
375
        zone.addr = start;
376
        zone.size = size;
377

    
378
        ret = kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
379
    }
380
#endif
381

    
382
    return ret;
383
}
384

    
385
int kvm_check_extension(KVMState *s, unsigned int extension)
386
{
387
    int ret;
388

    
389
    ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, extension);
390
    if (ret < 0) {
391
        ret = 0;
392
    }
393

    
394
    return ret;
395
}
396

    
397
int kvm_init(int smp_cpus)
398
{
399
    static const char upgrade_note[] =
400
        "Please upgrade to at least kernel 2.6.29 or recent kvm-kmod\n"
401
        "(see http://sourceforge.net/projects/kvm).\n";
402
    KVMState *s;
403
    int ret;
404
    int i;
405

    
406
    if (smp_cpus > 1) {
407
        fprintf(stderr, "No SMP KVM support, use '-smp 1'\n");
408
        return -EINVAL;
409
    }
410

    
411
    s = qemu_mallocz(sizeof(KVMState));
412

    
413
#ifdef KVM_CAP_SET_GUEST_DEBUG
414
    TAILQ_INIT(&s->kvm_sw_breakpoints);
415
#endif
416
    for (i = 0; i < ARRAY_SIZE(s->slots); i++)
417
        s->slots[i].slot = i;
418

    
419
    s->vmfd = -1;
420
    s->fd = open("/dev/kvm", O_RDWR);
421
    if (s->fd == -1) {
422
        fprintf(stderr, "Could not access KVM kernel module: %m\n");
423
        ret = -errno;
424
        goto err;
425
    }
426

    
427
    ret = kvm_ioctl(s, KVM_GET_API_VERSION, 0);
428
    if (ret < KVM_API_VERSION) {
429
        if (ret > 0)
430
            ret = -EINVAL;
431
        fprintf(stderr, "kvm version too old\n");
432
        goto err;
433
    }
434

    
435
    if (ret > KVM_API_VERSION) {
436
        ret = -EINVAL;
437
        fprintf(stderr, "kvm version not supported\n");
438
        goto err;
439
    }
440

    
441
    s->vmfd = kvm_ioctl(s, KVM_CREATE_VM, 0);
442
    if (s->vmfd < 0)
443
        goto err;
444

    
445
    /* initially, KVM allocated its own memory and we had to jump through
446
     * hooks to make phys_ram_base point to this.  Modern versions of KVM
447
     * just use a user allocated buffer so we can use regular pages
448
     * unmodified.  Make sure we have a sufficiently modern version of KVM.
449
     */
450
    if (!kvm_check_extension(s, KVM_CAP_USER_MEMORY)) {
451
        ret = -EINVAL;
452
        fprintf(stderr, "kvm does not support KVM_CAP_USER_MEMORY\n%s",
453
                upgrade_note);
454
        goto err;
455
    }
456

    
457
    /* There was a nasty bug in < kvm-80 that prevents memory slots from being
458
     * destroyed properly.  Since we rely on this capability, refuse to work
459
     * with any kernel without this capability. */
460
    if (!kvm_check_extension(s, KVM_CAP_DESTROY_MEMORY_REGION_WORKS)) {
461
        ret = -EINVAL;
462

    
463
        fprintf(stderr,
464
                "KVM kernel module broken (DESTROY_MEMORY_REGION).\n%s",
465
                upgrade_note);
466
        goto err;
467
    }
468

    
469
#ifdef KVM_CAP_COALESCED_MMIO
470
    s->coalesced_mmio = kvm_check_extension(s, KVM_CAP_COALESCED_MMIO);
471
#else
472
    s->coalesced_mmio = 0;
473
#endif
474

    
475
    s->broken_set_mem_region = 1;
476
#ifdef KVM_CAP_JOIN_MEMORY_REGIONS_WORKS
477
    ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, KVM_CAP_JOIN_MEMORY_REGIONS_WORKS);
478
    if (ret > 0) {
479
        s->broken_set_mem_region = 0;
480
    }
481
#endif
482

    
483
    ret = kvm_arch_init(s, smp_cpus);
484
    if (ret < 0)
485
        goto err;
486

    
487
    kvm_state = s;
488

    
489
    return 0;
490

    
491
err:
492
    if (s) {
493
        if (s->vmfd != -1)
494
            close(s->vmfd);
495
        if (s->fd != -1)
496
            close(s->fd);
497
    }
498
    qemu_free(s);
499

    
500
    return ret;
501
}
502

    
503
static int kvm_handle_io(CPUState *env, uint16_t port, void *data,
504
                         int direction, int size, uint32_t count)
505
{
506
    int i;
507
    uint8_t *ptr = data;
508

    
509
    for (i = 0; i < count; i++) {
510
        if (direction == KVM_EXIT_IO_IN) {
511
            switch (size) {
512
            case 1:
513
                stb_p(ptr, cpu_inb(env, port));
514
                break;
515
            case 2:
516
                stw_p(ptr, cpu_inw(env, port));
517
                break;
518
            case 4:
519
                stl_p(ptr, cpu_inl(env, port));
520
                break;
521
            }
522
        } else {
523
            switch (size) {
524
            case 1:
525
                cpu_outb(env, port, ldub_p(ptr));
526
                break;
527
            case 2:
528
                cpu_outw(env, port, lduw_p(ptr));
529
                break;
530
            case 4:
531
                cpu_outl(env, port, ldl_p(ptr));
532
                break;
533
            }
534
        }
535

    
536
        ptr += size;
537
    }
538

    
539
    return 1;
540
}
541

    
542
static void kvm_run_coalesced_mmio(CPUState *env, struct kvm_run *run)
543
{
544
#ifdef KVM_CAP_COALESCED_MMIO
545
    KVMState *s = kvm_state;
546
    if (s->coalesced_mmio) {
547
        struct kvm_coalesced_mmio_ring *ring;
548

    
549
        ring = (void *)run + (s->coalesced_mmio * TARGET_PAGE_SIZE);
550
        while (ring->first != ring->last) {
551
            struct kvm_coalesced_mmio *ent;
552

    
553
            ent = &ring->coalesced_mmio[ring->first];
554

    
555
            cpu_physical_memory_write(ent->phys_addr, ent->data, ent->len);
556
            /* FIXME smp_wmb() */
557
            ring->first = (ring->first + 1) % KVM_COALESCED_MMIO_MAX;
558
        }
559
    }
560
#endif
561
}
562

    
563
int kvm_cpu_exec(CPUState *env)
564
{
565
    struct kvm_run *run = env->kvm_run;
566
    int ret;
567

    
568
    dprintf("kvm_cpu_exec()\n");
569

    
570
    do {
571
        if (env->exit_request) {
572
            dprintf("interrupt exit requested\n");
573
            ret = 0;
574
            break;
575
        }
576

    
577
        kvm_arch_pre_run(env, run);
578
        ret = kvm_vcpu_ioctl(env, KVM_RUN, 0);
579
        kvm_arch_post_run(env, run);
580

    
581
        if (ret == -EINTR || ret == -EAGAIN) {
582
            dprintf("io window exit\n");
583
            ret = 0;
584
            break;
585
        }
586

    
587
        if (ret < 0) {
588
            dprintf("kvm run failed %s\n", strerror(-ret));
589
            abort();
590
        }
591

    
592
        kvm_run_coalesced_mmio(env, run);
593

    
594
        ret = 0; /* exit loop */
595
        switch (run->exit_reason) {
596
        case KVM_EXIT_IO:
597
            dprintf("handle_io\n");
598
            ret = kvm_handle_io(env, run->io.port,
599
                                (uint8_t *)run + run->io.data_offset,
600
                                run->io.direction,
601
                                run->io.size,
602
                                run->io.count);
603
            break;
604
        case KVM_EXIT_MMIO:
605
            dprintf("handle_mmio\n");
606
            cpu_physical_memory_rw(run->mmio.phys_addr,
607
                                   run->mmio.data,
608
                                   run->mmio.len,
609
                                   run->mmio.is_write);
610
            ret = 1;
611
            break;
612
        case KVM_EXIT_IRQ_WINDOW_OPEN:
613
            dprintf("irq_window_open\n");
614
            break;
615
        case KVM_EXIT_SHUTDOWN:
616
            dprintf("shutdown\n");
617
            qemu_system_reset_request();
618
            ret = 1;
619
            break;
620
        case KVM_EXIT_UNKNOWN:
621
            dprintf("kvm_exit_unknown\n");
622
            break;
623
        case KVM_EXIT_FAIL_ENTRY:
624
            dprintf("kvm_exit_fail_entry\n");
625
            break;
626
        case KVM_EXIT_EXCEPTION:
627
            dprintf("kvm_exit_exception\n");
628
            break;
629
        case KVM_EXIT_DEBUG:
630
            dprintf("kvm_exit_debug\n");
631
#ifdef KVM_CAP_SET_GUEST_DEBUG
632
            if (kvm_arch_debug(&run->debug.arch)) {
633
                gdb_set_stop_cpu(env);
634
                vm_stop(EXCP_DEBUG);
635
                env->exception_index = EXCP_DEBUG;
636
                return 0;
637
            }
638
            /* re-enter, this exception was guest-internal */
639
            ret = 1;
640
#endif /* KVM_CAP_SET_GUEST_DEBUG */
641
            break;
642
        default:
643
            dprintf("kvm_arch_handle_exit\n");
644
            ret = kvm_arch_handle_exit(env, run);
645
            break;
646
        }
647
    } while (ret > 0);
648

    
649
    if (env->exit_request) {
650
        env->exit_request = 0;
651
        env->exception_index = EXCP_INTERRUPT;
652
    }
653

    
654
    return ret;
655
}
656

    
657
void kvm_set_phys_mem(target_phys_addr_t start_addr,
658
                      ram_addr_t size,
659
                      ram_addr_t phys_offset)
660
{
661
    KVMState *s = kvm_state;
662
    ram_addr_t flags = phys_offset & ~TARGET_PAGE_MASK;
663
    KVMSlot *mem, old;
664
    int err;
665

    
666
    if (start_addr & ~TARGET_PAGE_MASK) {
667
        if (flags >= IO_MEM_UNASSIGNED) {
668
            if (!kvm_lookup_overlapping_slot(s, start_addr,
669
                                             start_addr + size)) {
670
                return;
671
            }
672
            fprintf(stderr, "Unaligned split of a KVM memory slot\n");
673
        } else {
674
            fprintf(stderr, "Only page-aligned memory slots supported\n");
675
        }
676
        abort();
677
    }
678

    
679
    /* KVM does not support read-only slots */
680
    phys_offset &= ~IO_MEM_ROM;
681

    
682
    while (1) {
683
        mem = kvm_lookup_overlapping_slot(s, start_addr, start_addr + size);
684
        if (!mem) {
685
            break;
686
        }
687

    
688
        if (flags < IO_MEM_UNASSIGNED && start_addr >= mem->start_addr &&
689
            (start_addr + size <= mem->start_addr + mem->memory_size) &&
690
            (phys_offset - start_addr == mem->phys_offset - mem->start_addr)) {
691
            /* The new slot fits into the existing one and comes with
692
             * identical parameters - nothing to be done. */
693
            return;
694
        }
695

    
696
        old = *mem;
697

    
698
        /* unregister the overlapping slot */
699
        mem->memory_size = 0;
700
        err = kvm_set_user_memory_region(s, mem);
701
        if (err) {
702
            fprintf(stderr, "%s: error unregistering overlapping slot: %s\n",
703
                    __func__, strerror(-err));
704
            abort();
705
        }
706

    
707
        /* Workaround for older KVM versions: we can't join slots, even not by
708
         * unregistering the previous ones and then registering the larger
709
         * slot. We have to maintain the existing fragmentation. Sigh.
710
         *
711
         * This workaround assumes that the new slot starts at the same
712
         * address as the first existing one. If not or if some overlapping
713
         * slot comes around later, we will fail (not seen in practice so far)
714
         * - and actually require a recent KVM version. */
715
        if (s->broken_set_mem_region &&
716
            old.start_addr == start_addr && old.memory_size < size &&
717
            flags < IO_MEM_UNASSIGNED) {
718
            mem = kvm_alloc_slot(s);
719
            mem->memory_size = old.memory_size;
720
            mem->start_addr = old.start_addr;
721
            mem->phys_offset = old.phys_offset;
722
            mem->flags = 0;
723

    
724
            err = kvm_set_user_memory_region(s, mem);
725
            if (err) {
726
                fprintf(stderr, "%s: error updating slot: %s\n", __func__,
727
                        strerror(-err));
728
                abort();
729
            }
730

    
731
            start_addr += old.memory_size;
732
            phys_offset += old.memory_size;
733
            size -= old.memory_size;
734
            continue;
735
        }
736

    
737
        /* register prefix slot */
738
        if (old.start_addr < start_addr) {
739
            mem = kvm_alloc_slot(s);
740
            mem->memory_size = start_addr - old.start_addr;
741
            mem->start_addr = old.start_addr;
742
            mem->phys_offset = old.phys_offset;
743
            mem->flags = 0;
744

    
745
            err = kvm_set_user_memory_region(s, mem);
746
            if (err) {
747
                fprintf(stderr, "%s: error registering prefix slot: %s\n",
748
                        __func__, strerror(-err));
749
                abort();
750
            }
751
        }
752

    
753
        /* register suffix slot */
754
        if (old.start_addr + old.memory_size > start_addr + size) {
755
            ram_addr_t size_delta;
756

    
757
            mem = kvm_alloc_slot(s);
758
            mem->start_addr = start_addr + size;
759
            size_delta = mem->start_addr - old.start_addr;
760
            mem->memory_size = old.memory_size - size_delta;
761
            mem->phys_offset = old.phys_offset + size_delta;
762
            mem->flags = 0;
763

    
764
            err = kvm_set_user_memory_region(s, mem);
765
            if (err) {
766
                fprintf(stderr, "%s: error registering suffix slot: %s\n",
767
                        __func__, strerror(-err));
768
                abort();
769
            }
770
        }
771
    }
772

    
773
    /* in case the KVM bug workaround already "consumed" the new slot */
774
    if (!size)
775
        return;
776

    
777
    /* KVM does not need to know about this memory */
778
    if (flags >= IO_MEM_UNASSIGNED)
779
        return;
780

    
781
    mem = kvm_alloc_slot(s);
782
    mem->memory_size = size;
783
    mem->start_addr = start_addr;
784
    mem->phys_offset = phys_offset;
785
    mem->flags = 0;
786

    
787
    err = kvm_set_user_memory_region(s, mem);
788
    if (err) {
789
        fprintf(stderr, "%s: error registering slot: %s\n", __func__,
790
                strerror(-err));
791
        abort();
792
    }
793
}
794

    
795
int kvm_ioctl(KVMState *s, int type, ...)
796
{
797
    int ret;
798
    void *arg;
799
    va_list ap;
800

    
801
    va_start(ap, type);
802
    arg = va_arg(ap, void *);
803
    va_end(ap);
804

    
805
    ret = ioctl(s->fd, type, arg);
806
    if (ret == -1)
807
        ret = -errno;
808

    
809
    return ret;
810
}
811

    
812
int kvm_vm_ioctl(KVMState *s, int type, ...)
813
{
814
    int ret;
815
    void *arg;
816
    va_list ap;
817

    
818
    va_start(ap, type);
819
    arg = va_arg(ap, void *);
820
    va_end(ap);
821

    
822
    ret = ioctl(s->vmfd, type, arg);
823
    if (ret == -1)
824
        ret = -errno;
825

    
826
    return ret;
827
}
828

    
829
int kvm_vcpu_ioctl(CPUState *env, int type, ...)
830
{
831
    int ret;
832
    void *arg;
833
    va_list ap;
834

    
835
    va_start(ap, type);
836
    arg = va_arg(ap, void *);
837
    va_end(ap);
838

    
839
    ret = ioctl(env->kvm_fd, type, arg);
840
    if (ret == -1)
841
        ret = -errno;
842

    
843
    return ret;
844
}
845

    
846
int kvm_has_sync_mmu(void)
847
{
848
#ifdef KVM_CAP_SYNC_MMU
849
    KVMState *s = kvm_state;
850

    
851
    return kvm_check_extension(s, KVM_CAP_SYNC_MMU);
852
#else
853
    return 0;
854
#endif
855
}
856

    
857
void kvm_setup_guest_memory(void *start, size_t size)
858
{
859
    if (!kvm_has_sync_mmu()) {
860
#ifdef MADV_DONTFORK
861
        int ret = madvise(start, size, MADV_DONTFORK);
862

    
863
        if (ret) {
864
            perror("madvice");
865
            exit(1);
866
        }
867
#else
868
        fprintf(stderr,
869
                "Need MADV_DONTFORK in absence of synchronous KVM MMU\n");
870
        exit(1);
871
#endif
872
    }
873
}
874

    
875
#ifdef KVM_CAP_SET_GUEST_DEBUG
876
struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *env,
877
                                                 target_ulong pc)
878
{
879
    struct kvm_sw_breakpoint *bp;
880

    
881
    TAILQ_FOREACH(bp, &env->kvm_state->kvm_sw_breakpoints, entry) {
882
        if (bp->pc == pc)
883
            return bp;
884
    }
885
    return NULL;
886
}
887

    
888
int kvm_sw_breakpoints_active(CPUState *env)
889
{
890
    return !TAILQ_EMPTY(&env->kvm_state->kvm_sw_breakpoints);
891
}
892

    
893
int kvm_update_guest_debug(CPUState *env, unsigned long reinject_trap)
894
{
895
    struct kvm_guest_debug dbg;
896

    
897
    dbg.control = 0;
898
    if (env->singlestep_enabled)
899
        dbg.control = KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP;
900

    
901
    kvm_arch_update_guest_debug(env, &dbg);
902
    dbg.control |= reinject_trap;
903

    
904
    return kvm_vcpu_ioctl(env, KVM_SET_GUEST_DEBUG, &dbg);
905
}
906

    
907
int kvm_insert_breakpoint(CPUState *current_env, target_ulong addr,
908
                          target_ulong len, int type)
909
{
910
    struct kvm_sw_breakpoint *bp;
911
    CPUState *env;
912
    int err;
913

    
914
    if (type == GDB_BREAKPOINT_SW) {
915
        bp = kvm_find_sw_breakpoint(current_env, addr);
916
        if (bp) {
917
            bp->use_count++;
918
            return 0;
919
        }
920

    
921
        bp = qemu_malloc(sizeof(struct kvm_sw_breakpoint));
922
        if (!bp)
923
            return -ENOMEM;
924

    
925
        bp->pc = addr;
926
        bp->use_count = 1;
927
        err = kvm_arch_insert_sw_breakpoint(current_env, bp);
928
        if (err) {
929
            free(bp);
930
            return err;
931
        }
932

    
933
        TAILQ_INSERT_HEAD(&current_env->kvm_state->kvm_sw_breakpoints,
934
                          bp, entry);
935
    } else {
936
        err = kvm_arch_insert_hw_breakpoint(addr, len, type);
937
        if (err)
938
            return err;
939
    }
940

    
941
    for (env = first_cpu; env != NULL; env = env->next_cpu) {
942
        err = kvm_update_guest_debug(env, 0);
943
        if (err)
944
            return err;
945
    }
946
    return 0;
947
}
948

    
949
int kvm_remove_breakpoint(CPUState *current_env, target_ulong addr,
950
                          target_ulong len, int type)
951
{
952
    struct kvm_sw_breakpoint *bp;
953
    CPUState *env;
954
    int err;
955

    
956
    if (type == GDB_BREAKPOINT_SW) {
957
        bp = kvm_find_sw_breakpoint(current_env, addr);
958
        if (!bp)
959
            return -ENOENT;
960

    
961
        if (bp->use_count > 1) {
962
            bp->use_count--;
963
            return 0;
964
        }
965

    
966
        err = kvm_arch_remove_sw_breakpoint(current_env, bp);
967
        if (err)
968
            return err;
969

    
970
        TAILQ_REMOVE(&current_env->kvm_state->kvm_sw_breakpoints, bp, entry);
971
        qemu_free(bp);
972
    } else {
973
        err = kvm_arch_remove_hw_breakpoint(addr, len, type);
974
        if (err)
975
            return err;
976
    }
977

    
978
    for (env = first_cpu; env != NULL; env = env->next_cpu) {
979
        err = kvm_update_guest_debug(env, 0);
980
        if (err)
981
            return err;
982
    }
983
    return 0;
984
}
985

    
986
void kvm_remove_all_breakpoints(CPUState *current_env)
987
{
988
    struct kvm_sw_breakpoint *bp, *next;
989
    KVMState *s = current_env->kvm_state;
990
    CPUState *env;
991

    
992
    TAILQ_FOREACH_SAFE(bp, &s->kvm_sw_breakpoints, entry, next) {
993
        if (kvm_arch_remove_sw_breakpoint(current_env, bp) != 0) {
994
            /* Try harder to find a CPU that currently sees the breakpoint. */
995
            for (env = first_cpu; env != NULL; env = env->next_cpu) {
996
                if (kvm_arch_remove_sw_breakpoint(env, bp) == 0)
997
                    break;
998
            }
999
        }
1000
    }
1001
    kvm_arch_remove_all_hw_breakpoints();
1002

    
1003
    for (env = first_cpu; env != NULL; env = env->next_cpu)
1004
        kvm_update_guest_debug(env, 0);
1005
}
1006

    
1007
#else /* !KVM_CAP_SET_GUEST_DEBUG */
1008

    
1009
int kvm_update_guest_debug(CPUState *env, unsigned long reinject_trap)
1010
{
1011
    return -EINVAL;
1012
}
1013

    
1014
int kvm_insert_breakpoint(CPUState *current_env, target_ulong addr,
1015
                          target_ulong len, int type)
1016
{
1017
    return -EINVAL;
1018
}
1019

    
1020
int kvm_remove_breakpoint(CPUState *current_env, target_ulong addr,
1021
                          target_ulong len, int type)
1022
{
1023
    return -EINVAL;
1024
}
1025

    
1026
void kvm_remove_all_breakpoints(CPUState *current_env)
1027
{
1028
}
1029
#endif /* !KVM_CAP_SET_GUEST_DEBUG */