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 "cpu.h"
24#include "qemu-common.h"
25#include "sysemu/sysemu.h"
26#include "hw/hw.h"
27#include "android/kvm.h"
28#include "exec/gdbstub.h"
29#include "sysemu/kvm.h"
30
31/* KVM uses PAGE_SIZE in it's definition of COALESCED_MMIO_MAX */
32#define PAGE_SIZE TARGET_PAGE_SIZE
33
34//#define DEBUG_KVM
35
36#ifdef DEBUG_KVM
37#define dprintf(fmt, ...) \
38    do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
39#else
40#define dprintf(fmt, ...) \
41    do { } while (0)
42#endif
43
44typedef struct KVMSlot
45{
46    hwaddr start_addr;
47    ram_addr_t memory_size;
48    ram_addr_t phys_offset;
49    int slot;
50    int flags;
51} KVMSlot;
52
53typedef struct kvm_dirty_log KVMDirtyLog;
54
55int kvm_allowed = 0;
56
57struct KVMState
58{
59    KVMSlot slots[32];
60    int fd;
61    int vmfd;
62    int coalesced_mmio;
63    int broken_set_mem_region;
64    int migration_log;
65#ifdef KVM_CAP_SET_GUEST_DEBUG
66    struct kvm_sw_breakpoint_head kvm_sw_breakpoints;
67#endif
68};
69
70static KVMState *kvm_state;
71
72static KVMSlot *kvm_alloc_slot(KVMState *s)
73{
74    int i;
75
76    for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
77        /* KVM private memory slots */
78        if (i >= 8 && i < 12)
79            continue;
80        if (s->slots[i].memory_size == 0)
81            return &s->slots[i];
82    }
83
84    fprintf(stderr, "%s: no free slot available\n", __func__);
85    abort();
86}
87
88static KVMSlot *kvm_lookup_matching_slot(KVMState *s,
89                                         hwaddr start_addr,
90                                         ram_addr_t size)
91{
92    int i;
93
94    for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
95        KVMSlot *mem = &s->slots[i];
96        if (start_addr == mem->start_addr && size == mem->memory_size) {
97            return mem;
98        }
99    }
100
101    return NULL;
102}
103
104/*
105 * Find overlapping slot with lowest start address
106 */
107static KVMSlot *kvm_lookup_overlapping_slot(KVMState *s,
108                                            hwaddr start_addr,
109                                            ram_addr_t size)
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        // Skip empty slots.
118        if (!mem->memory_size)
119            continue;
120
121        // Skip non-overlapping slots, conditions are:
122        //    start_addr + size <= mem->start_addr ||
123        //    start_addr >= mem->start_addr + mem->memory_size
124        //
125        // However, we want to avoid wrapping errors, so avoid
126        // additions and only compare positive values.
127        if (start_addr <= mem->start_addr) {
128            if (mem->start_addr - start_addr >= size) {
129                continue;
130            }
131        } else if (start_addr - mem->start_addr >= mem->memory_size) {
132            continue;
133        }
134
135        if (found && found->start_addr < mem->start_addr) {
136            continue;
137        }
138
139        found = mem;
140    }
141
142    return found;
143}
144
145static int kvm_set_user_memory_region(KVMState *s, KVMSlot *slot)
146{
147    struct kvm_userspace_memory_region mem;
148
149    mem.slot = slot->slot;
150    mem.guest_phys_addr = slot->start_addr;
151    mem.memory_size = slot->memory_size;
152    mem.userspace_addr = (unsigned long)qemu_get_ram_ptr(slot->phys_offset);
153    mem.flags = slot->flags;
154    if (s->migration_log) {
155        mem.flags |= KVM_MEM_LOG_DIRTY_PAGES;
156    }
157    return kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, &mem);
158}
159
160
161int kvm_init_vcpu(CPUState *cpu)
162{
163    KVMState *s = kvm_state;
164    long mmap_size;
165    int ret;
166
167    dprintf("kvm_init_vcpu\n");
168
169    ret = kvm_vm_ioctl(s, KVM_CREATE_VCPU, cpu->cpu_index);
170    if (ret < 0) {
171        dprintf("kvm_create_vcpu failed\n");
172        goto err;
173    }
174
175    cpu->kvm_fd = ret;
176    cpu->kvm_state = s;
177
178    mmap_size = kvm_ioctl(s, KVM_GET_VCPU_MMAP_SIZE, 0);
179    if (mmap_size < 0) {
180        dprintf("KVM_GET_VCPU_MMAP_SIZE failed\n");
181        goto err;
182    }
183
184    cpu->kvm_run = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED,
185                        cpu->kvm_fd, 0);
186    if (cpu->kvm_run == MAP_FAILED) {
187        ret = -errno;
188        dprintf("mmap'ing vcpu state failed\n");
189        goto err;
190    }
191
192    ret = kvm_arch_init_vcpu(cpu);
193
194err:
195    return ret;
196}
197
198int kvm_put_mp_state(CPUState *cpu)
199{
200    CPUArchState *env = cpu->env_ptr;
201    struct kvm_mp_state mp_state = { .mp_state = env->mp_state };
202
203    return kvm_vcpu_ioctl(cpu, KVM_SET_MP_STATE, &mp_state);
204}
205
206int kvm_get_mp_state(CPUState *cpu)
207{
208    struct kvm_mp_state mp_state;
209    int ret;
210
211    ret = kvm_vcpu_ioctl(cpu, KVM_GET_MP_STATE, &mp_state);
212    if (ret < 0) {
213        return ret;
214    }
215    CPUArchState *env = cpu->env_ptr;
216    env->mp_state = mp_state.mp_state;
217    return 0;
218}
219
220int kvm_sync_vcpus(void)
221{
222    CPUState *cpu;
223
224    CPU_FOREACH(cpu) {
225        int ret = kvm_arch_put_registers(cpu);
226        if (ret)
227            return ret;
228    }
229
230    return 0;
231}
232
233/*
234 * dirty pages logging control
235 */
236static int kvm_dirty_pages_log_change(hwaddr phys_addr,
237                                      ram_addr_t size, int flags, int mask)
238{
239    KVMState *s = kvm_state;
240    KVMSlot *mem = kvm_lookup_matching_slot(s, phys_addr, size);
241    int old_flags;
242
243    if (mem == NULL)  {
244            fprintf(stderr, "BUG: %s: invalid parameters " TARGET_FMT_plx "-"
245                    TARGET_FMT_plx "\n", __func__, (hwaddr)phys_addr,
246                    (hwaddr)(phys_addr + size - 1));
247            return -EINVAL;
248    }
249
250    old_flags = mem->flags;
251
252    flags = (mem->flags & ~mask) | flags;
253    mem->flags = flags;
254
255    /* If nothing changed effectively, no need to issue ioctl */
256    if (s->migration_log) {
257        flags |= KVM_MEM_LOG_DIRTY_PAGES;
258    }
259    if (flags == old_flags) {
260            return 0;
261    }
262
263    return kvm_set_user_memory_region(s, mem);
264}
265
266int kvm_log_start(hwaddr phys_addr, ram_addr_t size)
267{
268        return kvm_dirty_pages_log_change(phys_addr, size,
269                                          KVM_MEM_LOG_DIRTY_PAGES,
270                                          KVM_MEM_LOG_DIRTY_PAGES);
271}
272
273int kvm_log_stop(hwaddr phys_addr, ram_addr_t size)
274{
275        return kvm_dirty_pages_log_change(phys_addr, size,
276                                          0,
277                                          KVM_MEM_LOG_DIRTY_PAGES);
278}
279
280int kvm_set_migration_log(int enable)
281{
282    KVMState *s = kvm_state;
283    KVMSlot *mem;
284    int i, err;
285
286    s->migration_log = enable;
287
288    for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
289        mem = &s->slots[i];
290
291        if (!!(mem->flags & KVM_MEM_LOG_DIRTY_PAGES) == enable) {
292            continue;
293        }
294        err = kvm_set_user_memory_region(s, mem);
295        if (err) {
296            return err;
297        }
298    }
299    return 0;
300}
301
302/**
303 * kvm_physical_sync_dirty_bitmap - Grab dirty bitmap from kernel space
304 * This function updates qemu's dirty bitmap using cpu_physical_memory_set_dirty().
305 * This means all bits are set to dirty.
306 *
307 * @start_add: start of logged region.
308 * @end_addr: end of logged region.
309 */
310int kvm_physical_sync_dirty_bitmap(hwaddr start_addr,
311                                   hwaddr end_addr)
312{
313    KVMState *s = kvm_state;
314    unsigned long size, allocated_size = 0;
315    hwaddr phys_addr;
316    ram_addr_t addr;
317    KVMDirtyLog d;
318    KVMSlot *mem;
319    int ret = 0;
320
321    d.dirty_bitmap = NULL;
322    while (start_addr < end_addr) {
323        ram_addr_t start_size = (ram_addr_t)(end_addr - start_addr);
324
325        mem = kvm_lookup_overlapping_slot(s, start_addr, start_size);
326        if (mem == NULL) {
327            break;
328        }
329
330        size = ((mem->memory_size >> TARGET_PAGE_BITS) + 7) / 8;
331        if (size > allocated_size) {
332            d.dirty_bitmap = g_realloc(d.dirty_bitmap, size);
333            allocated_size = size;
334        }
335        memset(d.dirty_bitmap, 0, size);
336
337        d.slot = mem->slot;
338
339        if (kvm_vm_ioctl(s, KVM_GET_DIRTY_LOG, &d) == -1) {
340            dprintf("ioctl failed %d\n", errno);
341            ret = -1;
342            break;
343        }
344
345        for (phys_addr = mem->start_addr, addr = mem->phys_offset;
346             phys_addr - mem->start_addr < mem->memory_size;
347             phys_addr += TARGET_PAGE_SIZE, addr += TARGET_PAGE_SIZE) {
348            unsigned long *bitmap = (unsigned long *)d.dirty_bitmap;
349            unsigned nr = (phys_addr - mem->start_addr) >> TARGET_PAGE_BITS;
350            unsigned word = nr / (sizeof(*bitmap) * 8);
351            unsigned bit = nr % (sizeof(*bitmap) * 8);
352
353            if ((bitmap[word] >> bit) & 1) {
354                cpu_physical_memory_set_dirty(addr);
355            }
356        }
357        start_addr = phys_addr;
358        if (!start_addr) {
359            // Handle wrap-around, which happens when a slot is mapped
360            // at the end of the physical address space.
361            break;
362        }
363    }
364    g_free(d.dirty_bitmap);
365
366    return ret;
367}
368
369int kvm_coalesce_mmio_region(hwaddr start, ram_addr_t size)
370{
371    int ret = -ENOSYS;
372#ifdef KVM_CAP_COALESCED_MMIO
373    KVMState *s = kvm_state;
374
375    if (s->coalesced_mmio) {
376        struct kvm_coalesced_mmio_zone zone;
377
378        zone.addr = start;
379        zone.size = size;
380
381        ret = kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
382    }
383#endif
384
385    return ret;
386}
387
388int kvm_uncoalesce_mmio_region(hwaddr start, ram_addr_t size)
389{
390    int ret = -ENOSYS;
391#ifdef KVM_CAP_COALESCED_MMIO
392    KVMState *s = kvm_state;
393
394    if (s->coalesced_mmio) {
395        struct kvm_coalesced_mmio_zone zone;
396
397        zone.addr = start;
398        zone.size = size;
399
400        ret = kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
401    }
402#endif
403
404    return ret;
405}
406
407int kvm_check_extension(KVMState *s, unsigned int extension)
408{
409    int ret;
410
411    ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, extension);
412    if (ret < 0) {
413        ret = 0;
414    }
415
416    return ret;
417}
418
419static void kvm_reset_vcpus(void *opaque)
420{
421    kvm_sync_vcpus();
422}
423
424int kvm_init(int smp_cpus)
425{
426    static const char upgrade_note[] =
427        "Please upgrade to at least kernel 2.6.29 or recent kvm-kmod\n"
428        "(see http://sourceforge.net/projects/kvm).\n";
429    KVMState *s;
430    int ret;
431    int i;
432
433    if (smp_cpus > 1) {
434        fprintf(stderr, "No SMP KVM support, use '-smp 1'\n");
435        return -EINVAL;
436    }
437
438    s = g_malloc0(sizeof(KVMState));
439
440#ifdef KVM_CAP_SET_GUEST_DEBUG
441    QTAILQ_INIT(&s->kvm_sw_breakpoints);
442#endif
443    for (i = 0; i < ARRAY_SIZE(s->slots); i++)
444        s->slots[i].slot = i;
445
446    char* kvm_device = getenv(KVM_DEVICE_NAME_ENV);
447    if (NULL == kvm_device) {
448      kvm_device = "/dev/kvm";
449    }
450
451    s->vmfd = -1;
452    s->fd = open(kvm_device, O_RDWR);
453    if (s->fd == -1) {
454        ret = -errno;
455        fprintf(stderr, "Could not access KVM kernel module: %m\n");
456        goto err;
457    }
458
459    ret = kvm_ioctl(s, KVM_GET_API_VERSION, 0);
460    if (ret < KVM_API_VERSION) {
461        if (ret > 0)
462            ret = -EINVAL;
463        fprintf(stderr, "kvm version too old\n");
464        goto err;
465    }
466
467    if (ret > KVM_API_VERSION) {
468        ret = -EINVAL;
469        fprintf(stderr, "kvm version not supported\n");
470        goto err;
471    }
472
473    do {
474      s->vmfd = kvm_ioctl(s, KVM_CREATE_VM, 0);
475    } while (s->vmfd < 0 && (EINTR == errno || EAGAIN == errno));
476
477    if (s->vmfd < 0) {
478        ret = -errno;
479        fprintf(stderr, "ioctl(KVM_CREATE_VM) failed: %d %s\n", errno, strerror(errno));
480        goto err;
481    }
482
483    /* initially, KVM allocated its own memory and we had to jump through
484     * hooks to make phys_ram_base point to this.  Modern versions of KVM
485     * just use a user allocated buffer so we can use regular pages
486     * unmodified.  Make sure we have a sufficiently modern version of KVM.
487     */
488    if (!kvm_check_extension(s, KVM_CAP_USER_MEMORY)) {
489        ret = -EINVAL;
490        fprintf(stderr, "kvm does not support KVM_CAP_USER_MEMORY\n%s",
491                upgrade_note);
492        goto err;
493    }
494
495    /* There was a nasty bug in < kvm-80 that prevents memory slots from being
496     * destroyed properly.  Since we rely on this capability, refuse to work
497     * with any kernel without this capability. */
498    if (!kvm_check_extension(s, KVM_CAP_DESTROY_MEMORY_REGION_WORKS)) {
499        ret = -EINVAL;
500
501        fprintf(stderr,
502                "KVM kernel module broken (DESTROY_MEMORY_REGION).\n%s",
503                upgrade_note);
504        goto err;
505    }
506
507#ifdef KVM_CAP_COALESCED_MMIO
508    s->coalesced_mmio = kvm_check_extension(s, KVM_CAP_COALESCED_MMIO);
509#else
510    s->coalesced_mmio = 0;
511#endif
512
513    s->broken_set_mem_region = 1;
514#ifdef KVM_CAP_JOIN_MEMORY_REGIONS_WORKS
515    ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, KVM_CAP_JOIN_MEMORY_REGIONS_WORKS);
516    if (ret > 0) {
517        s->broken_set_mem_region = 0;
518    }
519#endif
520
521    ret = kvm_arch_init(s, smp_cpus);
522    if (ret < 0)
523        goto err;
524
525    qemu_register_reset(kvm_reset_vcpus, INT_MAX, NULL);
526
527    kvm_state = s;
528
529    return 0;
530
531err:
532    if (s) {
533        if (s->vmfd != -1)
534            close(s->vmfd);
535        if (s->fd != -1)
536            close(s->fd);
537    }
538    g_free(s);
539
540    return ret;
541}
542
543static int kvm_handle_io(CPUState *cpu, uint16_t port, void *data,
544                         int direction, int size, uint32_t count)
545{
546    int i;
547    uint8_t *ptr = data;
548
549    for (i = 0; i < count; i++) {
550        if (direction == KVM_EXIT_IO_IN) {
551            switch (size) {
552            case 1:
553                stb_p(ptr, cpu_inb(port));
554                break;
555            case 2:
556                stw_p(ptr, cpu_inw(port));
557                break;
558            case 4:
559                stl_p(ptr, cpu_inl(port));
560                break;
561            }
562        } else {
563            switch (size) {
564            case 1:
565                cpu_outb(port, ldub_p(ptr));
566                break;
567            case 2:
568                cpu_outw(port, lduw_p(ptr));
569                break;
570            case 4:
571                cpu_outl(port, ldl_p(ptr));
572                break;
573            }
574        }
575
576        ptr += size;
577    }
578
579    return 1;
580}
581
582static void kvm_run_coalesced_mmio(CPUState *cpu, struct kvm_run *run)
583{
584#ifdef KVM_CAP_COALESCED_MMIO
585    KVMState *s = kvm_state;
586    if (s->coalesced_mmio) {
587        struct kvm_coalesced_mmio_ring *ring;
588
589        ring = (void *)run + (s->coalesced_mmio * TARGET_PAGE_SIZE);
590        while (ring->first != ring->last) {
591            struct kvm_coalesced_mmio *ent;
592
593            ent = &ring->coalesced_mmio[ring->first];
594
595            cpu_physical_memory_write(ent->phys_addr, ent->data, ent->len);
596            /* FIXME smp_wmb() */
597            ring->first = (ring->first + 1) % KVM_COALESCED_MMIO_MAX;
598        }
599    }
600#endif
601}
602
603int kvm_cpu_exec(CPUState *cpu)
604{
605    CPUArchState *env = cpu->env_ptr;
606    struct kvm_run *run = cpu->kvm_run;
607    int ret;
608
609    dprintf("kvm_cpu_exec()\n");
610
611    do {
612        if (cpu->exit_request) {
613            dprintf("interrupt exit requested\n");
614            ret = 0;
615            break;
616        }
617
618        kvm_arch_pre_run(cpu, run);
619        ret = kvm_arch_vcpu_run(cpu);
620        kvm_arch_post_run(cpu, run);
621
622        if (ret == -EINTR || ret == -EAGAIN) {
623            dprintf("io window exit\n");
624            ret = 0;
625            break;
626        }
627
628        if (ret < 0) {
629            dprintf("kvm run failed %s\n", strerror(-ret));
630            abort();
631        }
632
633        kvm_run_coalesced_mmio(cpu, run);
634
635        ret = 0; /* exit loop */
636        switch (run->exit_reason) {
637        case KVM_EXIT_IO:
638            dprintf("handle_io\n");
639            ret = kvm_handle_io(cpu, run->io.port,
640                                (uint8_t *)run + run->io.data_offset,
641                                run->io.direction,
642                                run->io.size,
643                                run->io.count);
644            break;
645        case KVM_EXIT_MMIO:
646            dprintf("handle_mmio\n");
647            cpu_physical_memory_rw(run->mmio.phys_addr,
648                                   run->mmio.data,
649                                   run->mmio.len,
650                                   run->mmio.is_write);
651            ret = 1;
652            break;
653        case KVM_EXIT_IRQ_WINDOW_OPEN:
654            dprintf("irq_window_open\n");
655            break;
656        case KVM_EXIT_SHUTDOWN:
657            dprintf("shutdown\n");
658            qemu_system_reset_request();
659            ret = 1;
660            break;
661        case KVM_EXIT_UNKNOWN:
662            dprintf("kvm_exit_unknown\n");
663            break;
664        case KVM_EXIT_FAIL_ENTRY:
665            dprintf("kvm_exit_fail_entry\n");
666            break;
667        case KVM_EXIT_EXCEPTION:
668            dprintf("kvm_exit_exception\n");
669            break;
670        case KVM_EXIT_DEBUG:
671            dprintf("kvm_exit_debug\n");
672#ifdef KVM_CAP_SET_GUEST_DEBUG
673            if (kvm_arch_debug(&run->debug.arch)) {
674                gdb_set_stop_cpu(cpu);
675                vm_stop(EXCP_DEBUG);\
676                env->exception_index = EXCP_DEBUG;
677                return 0;
678            }
679            /* re-enter, this exception was guest-internal */
680            ret = 1;
681#endif /* KVM_CAP_SET_GUEST_DEBUG */
682            break;
683        default:
684            dprintf("kvm_arch_handle_exit\n");
685            ret = kvm_arch_handle_exit(cpu, run);
686            break;
687        }
688    } while (ret > 0);
689
690    if (cpu->exit_request) {
691        cpu->exit_request = 0;
692        env->exception_index = EXCP_INTERRUPT;
693    }
694
695    return ret;
696}
697
698void kvm_set_phys_mem(hwaddr start_addr,
699                      ram_addr_t size,
700                      ram_addr_t phys_offset)
701{
702    KVMState *s = kvm_state;
703    ram_addr_t flags = phys_offset & ~TARGET_PAGE_MASK;
704    KVMSlot *mem, old;
705    int err;
706
707    if (start_addr & ~TARGET_PAGE_MASK) {
708        if (flags >= IO_MEM_UNASSIGNED) {
709            if (!kvm_lookup_overlapping_slot(s, start_addr, size)) {
710                return;
711            }
712            fprintf(stderr, "Unaligned split of a KVM memory slot\n");
713        } else {
714            fprintf(stderr, "Only page-aligned memory slots supported\n");
715        }
716        abort();
717    }
718
719    /* KVM does not support read-only slots */
720    phys_offset &= ~IO_MEM_ROM;
721
722    while (1) {
723        mem = kvm_lookup_overlapping_slot(s, start_addr, size);
724        if (!mem) {
725            break;
726        }
727
728        if (flags < IO_MEM_UNASSIGNED && start_addr >= mem->start_addr &&
729            (start_addr + size <= mem->start_addr + mem->memory_size) &&
730            (phys_offset - start_addr == mem->phys_offset - mem->start_addr)) {
731            /* The new slot fits into the existing one and comes with
732             * identical parameters - nothing to be done. */
733            return;
734        }
735
736        old = *mem;
737
738        /* unregister the overlapping slot */
739        mem->memory_size = 0;
740        err = kvm_set_user_memory_region(s, mem);
741        if (err) {
742            fprintf(stderr, "%s: error unregistering overlapping slot: %s\n",
743                    __func__, strerror(-err));
744            abort();
745        }
746
747        /* Workaround for older KVM versions: we can't join slots, even not by
748         * unregistering the previous ones and then registering the larger
749         * slot. We have to maintain the existing fragmentation. Sigh.
750         *
751         * This workaround assumes that the new slot starts at the same
752         * address as the first existing one. If not or if some overlapping
753         * slot comes around later, we will fail (not seen in practice so far)
754         * - and actually require a recent KVM version. */
755        if (s->broken_set_mem_region &&
756            old.start_addr == start_addr && old.memory_size < size &&
757            flags < IO_MEM_UNASSIGNED) {
758            mem = kvm_alloc_slot(s);
759            mem->memory_size = old.memory_size;
760            mem->start_addr = old.start_addr;
761            mem->phys_offset = old.phys_offset;
762            mem->flags = 0;
763
764            err = kvm_set_user_memory_region(s, mem);
765            if (err) {
766                fprintf(stderr, "%s: error updating slot: %s\n", __func__,
767                        strerror(-err));
768                abort();
769            }
770
771            start_addr += old.memory_size;
772            phys_offset += old.memory_size;
773            size -= old.memory_size;
774            continue;
775        }
776
777        /* register prefix slot */
778        if (old.start_addr < start_addr) {
779            mem = kvm_alloc_slot(s);
780            mem->memory_size = start_addr - old.start_addr;
781            mem->start_addr = old.start_addr;
782            mem->phys_offset = old.phys_offset;
783            mem->flags = 0;
784
785            err = kvm_set_user_memory_region(s, mem);
786            if (err) {
787                fprintf(stderr, "%s: error registering prefix slot: %s\n",
788                        __func__, strerror(-err));
789                abort();
790            }
791        }
792
793        /* register suffix slot */
794        if (old.start_addr + old.memory_size > start_addr + size) {
795            ram_addr_t size_delta;
796
797            mem = kvm_alloc_slot(s);
798            mem->start_addr = start_addr + size;
799            size_delta = mem->start_addr - old.start_addr;
800            mem->memory_size = old.memory_size - size_delta;
801            mem->phys_offset = old.phys_offset + size_delta;
802            mem->flags = 0;
803
804            err = kvm_set_user_memory_region(s, mem);
805            if (err) {
806                fprintf(stderr, "%s: error registering suffix slot: %s\n",
807                        __func__, strerror(-err));
808                abort();
809            }
810        }
811    }
812
813    /* in case the KVM bug workaround already "consumed" the new slot */
814    if (!size)
815        return;
816
817    /* KVM does not need to know about this memory */
818    if (flags >= IO_MEM_UNASSIGNED)
819        return;
820
821    mem = kvm_alloc_slot(s);
822    mem->memory_size = size;
823    mem->start_addr = start_addr;
824    mem->phys_offset = phys_offset;
825    mem->flags = 0;
826
827    err = kvm_set_user_memory_region(s, mem);
828    if (err) {
829        fprintf(stderr, "%s: error registering slot: %s\n", __func__,
830                strerror(-err));
831        abort();
832    }
833}
834
835int kvm_ioctl(KVMState *s, int type, ...)
836{
837    int ret;
838    void *arg;
839    va_list ap;
840
841    va_start(ap, type);
842    arg = va_arg(ap, void *);
843    va_end(ap);
844
845    ret = ioctl(s->fd, type, arg);
846    if (ret == -1)
847        ret = -errno;
848
849    return ret;
850}
851
852int kvm_vm_ioctl(KVMState *s, int type, ...)
853{
854    int ret;
855    void *arg;
856    va_list ap;
857
858    va_start(ap, type);
859    arg = va_arg(ap, void *);
860    va_end(ap);
861
862    ret = ioctl(s->vmfd, type, arg);
863    if (ret == -1)
864        ret = -errno;
865
866    return ret;
867}
868
869int kvm_vcpu_ioctl(CPUState *cpu, int type, ...)
870{
871    int ret;
872    void *arg;
873    va_list ap;
874
875    va_start(ap, type);
876    arg = va_arg(ap, void *);
877    va_end(ap);
878
879    ret = ioctl(cpu->kvm_fd, type, arg);
880    if (ret == -1)
881        ret = -errno;
882
883    return ret;
884}
885
886int kvm_has_sync_mmu(void)
887{
888#ifdef KVM_CAP_SYNC_MMU
889    KVMState *s = kvm_state;
890
891    return kvm_check_extension(s, KVM_CAP_SYNC_MMU);
892#else
893    return 0;
894#endif
895}
896
897void kvm_setup_guest_memory(void *start, size_t size)
898{
899    if (!kvm_has_sync_mmu()) {
900#ifdef MADV_DONTFORK
901        int ret = madvise(start, size, MADV_DONTFORK);
902
903        if (ret) {
904            perror("madvice");
905            exit(1);
906        }
907#else
908        fprintf(stderr,
909                "Need MADV_DONTFORK in absence of synchronous KVM MMU\n");
910        exit(1);
911#endif
912    }
913}
914
915#ifdef KVM_CAP_SET_GUEST_DEBUG
916struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *cpu,
917                                                 target_ulong pc)
918{
919    struct kvm_sw_breakpoint *bp;
920
921    QTAILQ_FOREACH(bp, &cpu->kvm_state->kvm_sw_breakpoints, entry) {
922        if (bp->pc == pc)
923            return bp;
924    }
925    return NULL;
926}
927
928int kvm_sw_breakpoints_active(CPUState *cpu)
929{
930    return !QTAILQ_EMPTY(&cpu->kvm_state->kvm_sw_breakpoints);
931}
932
933int kvm_update_guest_debug(CPUState *cpu, unsigned long reinject_trap)
934{
935    struct kvm_guest_debug dbg;
936
937    dbg.control = 0;
938    if (cpu->singlestep_enabled)
939        dbg.control = KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP;
940
941    kvm_arch_update_guest_debug(cpu, &dbg);
942    dbg.control |= reinject_trap;
943
944    return kvm_vcpu_ioctl(cpu, KVM_SET_GUEST_DEBUG, &dbg);
945}
946
947int kvm_insert_breakpoint(CPUState *cpu, target_ulong addr,
948                          target_ulong len, int type)
949{
950    struct kvm_sw_breakpoint *bp;
951    int err;
952
953    if (type == GDB_BREAKPOINT_SW) {
954        bp = kvm_find_sw_breakpoint(cpu, addr);
955        if (bp) {
956            bp->use_count++;
957            return 0;
958        }
959
960        bp = g_malloc(sizeof(struct kvm_sw_breakpoint));
961        if (!bp)
962            return -ENOMEM;
963
964        bp->pc = addr;
965        bp->use_count = 1;
966        err = kvm_arch_insert_sw_breakpoint(cpu, bp);
967        if (err) {
968            free(bp);
969            return err;
970        }
971
972        QTAILQ_INSERT_HEAD(&cpu->kvm_state->kvm_sw_breakpoints,
973                          bp, entry);
974    } else {
975        err = kvm_arch_insert_hw_breakpoint(addr, len, type);
976        if (err)
977            return err;
978    }
979
980    CPU_FOREACH(cpu) {
981        err = kvm_update_guest_debug(cpu, 0);
982        if (err)
983            return err;
984    }
985    return 0;
986}
987
988int kvm_remove_breakpoint(CPUState *cpu, target_ulong addr,
989                          target_ulong len, int type)
990{
991    struct kvm_sw_breakpoint *bp;
992    int err;
993
994    if (type == GDB_BREAKPOINT_SW) {
995        bp = kvm_find_sw_breakpoint(cpu, addr);
996        if (!bp)
997            return -ENOENT;
998
999        if (bp->use_count > 1) {
1000            bp->use_count--;
1001            return 0;
1002        }
1003
1004        err = kvm_arch_remove_sw_breakpoint(cpu, bp);
1005        if (err)
1006            return err;
1007
1008        QTAILQ_REMOVE(&cpu->kvm_state->kvm_sw_breakpoints, bp, entry);
1009        g_free(bp);
1010    } else {
1011        err = kvm_arch_remove_hw_breakpoint(addr, len, type);
1012        if (err)
1013            return err;
1014    }
1015
1016    CPU_FOREACH(cpu) {
1017        err = kvm_update_guest_debug(cpu, 0);
1018        if (err)
1019            return err;
1020    }
1021    return 0;
1022}
1023
1024void kvm_remove_all_breakpoints(CPUState *cpu)
1025{
1026    struct kvm_sw_breakpoint *bp, *next;
1027    KVMState *s = cpu->kvm_state;
1028
1029    QTAILQ_FOREACH_SAFE(bp, &s->kvm_sw_breakpoints, entry, next) {
1030        if (kvm_arch_remove_sw_breakpoint(cpu, bp) != 0) {
1031            /* Try harder to find a CPU that currently sees the breakpoint. */
1032            CPU_FOREACH(cpu) {
1033                if (kvm_arch_remove_sw_breakpoint(cpu, bp) == 0)
1034                    break;
1035            }
1036        }
1037    }
1038    kvm_arch_remove_all_hw_breakpoints();
1039
1040    CPU_FOREACH(cpu) {
1041        kvm_update_guest_debug(cpu, 0);
1042    }
1043}
1044
1045#else /* !KVM_CAP_SET_GUEST_DEBUG */
1046
1047int kvm_update_guest_debug(CPUState *cpu, unsigned long reinject_trap)
1048{
1049    return -EINVAL;
1050}
1051
1052int kvm_insert_breakpoint(CPUState *cpu, target_ulong addr,
1053                          target_ulong len, int type)
1054{
1055    return -EINVAL;
1056}
1057
1058int kvm_remove_breakpoint(CPUState *cpu, target_ulong addr,
1059                          target_ulong len, int type)
1060{
1061    return -EINVAL;
1062}
1063
1064void kvm_remove_all_breakpoints(CPUState *cpu)
1065{
1066}
1067#endif /* !KVM_CAP_SET_GUEST_DEBUG */
1068