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03c63b9452
qemu/kvm-all.c
Sheng Yang 62a2744ca0 kvm: Flush coalesced MMIO buffer periodly 
The default action of coalesced MMIO is, cache the writing in buffer, until:
1. The buffer is full.
2. Or the exit to QEmu due to other reasons.

But this would result in a very late writing in some condition.
1. The each time write to MMIO content is small.
2. The writing interval is big.
3. No need for input or accessing other devices frequently.

This issue was observed in a experimental embbed system. The test image
simply print "test" every 1 seconds. The output in QEmu meets expectation,
but the output in KVM is delayed for seconds.

Per Avi's suggestion, I hooked flushing coalesced MMIO buffer in VGA update
handler. By this way, We don't need vcpu explicit exit to QEmu to
handle this issue.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-02-03 19:47:33 -02:00

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/*
* QEMU KVM support
*
* Copyright IBM, Corp. 2008
* Red Hat, Inc. 2008
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
* Glauber Costa <gcosta@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <stdarg.h>
#include <linux/kvm.h>
#include "qemu-common.h"
#include "sysemu.h"
#include "hw/hw.h"
#include "gdbstub.h"
#include "kvm.h"
/* KVM uses PAGE_SIZE in it's definition of COALESCED_MMIO_MAX */
#define PAGE_SIZE TARGET_PAGE_SIZE
//#define DEBUG_KVM
#ifdef DEBUG_KVM
#define dprintf(fmt, ...) \
do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
#else
#define dprintf(fmt, ...) \
do { } while (0)
#endif
typedef struct KVMSlot
{
target_phys_addr_t start_addr;
ram_addr_t memory_size;
ram_addr_t phys_offset;
int slot;
int flags;
} KVMSlot;
typedef struct kvm_dirty_log KVMDirtyLog;
int kvm_allowed = 0;
struct KVMState
{
KVMSlot slots[32];
int fd;
int vmfd;
int regs_modified;
int coalesced_mmio;
#ifdef KVM_CAP_COALESCED_MMIO
struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
#endif
int broken_set_mem_region;
int migration_log;
int vcpu_events;
#ifdef KVM_CAP_SET_GUEST_DEBUG
struct kvm_sw_breakpoint_head kvm_sw_breakpoints;
#endif
int irqchip_in_kernel;
int pit_in_kernel;
};
static KVMState *kvm_state;
static KVMSlot *kvm_alloc_slot(KVMState *s)
{
int i;
for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
/* KVM private memory slots */
if (i >= 8 && i < 12)
continue;
if (s->slots[i].memory_size == 0)
return &s->slots[i];
}
fprintf(stderr, "%s: no free slot available\n", __func__);
abort();
}
static KVMSlot *kvm_lookup_matching_slot(KVMState *s,
target_phys_addr_t start_addr,
target_phys_addr_t end_addr)
{
int i;
for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
KVMSlot *mem = &s->slots[i];
if (start_addr == mem->start_addr &&
end_addr == mem->start_addr + mem->memory_size) {
return mem;
}
}
return NULL;
}
/*
* Find overlapping slot with lowest start address
*/
static KVMSlot *kvm_lookup_overlapping_slot(KVMState *s,
target_phys_addr_t start_addr,
target_phys_addr_t end_addr)
{
KVMSlot *found = NULL;
int i;
for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
KVMSlot *mem = &s->slots[i];
if (mem->memory_size == 0 ||
(found && found->start_addr < mem->start_addr)) {
continue;
}
if (end_addr > mem->start_addr &&
start_addr < mem->start_addr + mem->memory_size) {
found = mem;
}
}
return found;
}
static int kvm_set_user_memory_region(KVMState *s, KVMSlot *slot)
{
struct kvm_userspace_memory_region mem;
mem.slot = slot->slot;
mem.guest_phys_addr = slot->start_addr;
mem.memory_size = slot->memory_size;
mem.userspace_addr = (unsigned long)qemu_get_ram_ptr(slot->phys_offset);
mem.flags = slot->flags;
if (s->migration_log) {
mem.flags |= KVM_MEM_LOG_DIRTY_PAGES;
}
return kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, &mem);
}
static void kvm_reset_vcpu(void *opaque)
{
CPUState *env = opaque;
kvm_arch_reset_vcpu(env);
if (kvm_arch_put_registers(env)) {
fprintf(stderr, "Fatal: kvm vcpu reset failed\n");
abort();
}
}
int kvm_irqchip_in_kernel(void)
{
return kvm_state->irqchip_in_kernel;
}
int kvm_pit_in_kernel(void)
{
return kvm_state->pit_in_kernel;
}
int kvm_init_vcpu(CPUState *env)
{
KVMState *s = kvm_state;
long mmap_size;
int ret;
dprintf("kvm_init_vcpu\n");
ret = kvm_vm_ioctl(s, KVM_CREATE_VCPU, env->cpu_index);
if (ret < 0) {
dprintf("kvm_create_vcpu failed\n");
goto err;
}
env->kvm_fd = ret;
env->kvm_state = s;
mmap_size = kvm_ioctl(s, KVM_GET_VCPU_MMAP_SIZE, 0);
if (mmap_size < 0) {
dprintf("KVM_GET_VCPU_MMAP_SIZE failed\n");
goto err;
}
env->kvm_run = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED,
env->kvm_fd, 0);
if (env->kvm_run == MAP_FAILED) {
ret = -errno;
dprintf("mmap'ing vcpu state failed\n");
goto err;
}
#ifdef KVM_CAP_COALESCED_MMIO
if (s->coalesced_mmio && !s->coalesced_mmio_ring)
s->coalesced_mmio_ring = (void *) env->kvm_run +
s->coalesced_mmio * PAGE_SIZE;
#endif
ret = kvm_arch_init_vcpu(env);
if (ret == 0) {
qemu_register_reset(kvm_reset_vcpu, env);
kvm_arch_reset_vcpu(env);
ret = kvm_arch_put_registers(env);
}
err:
return ret;
}
/*
* dirty pages logging control
*/
static int kvm_dirty_pages_log_change(target_phys_addr_t phys_addr,
ram_addr_t size, int flags, int mask)
{
KVMState *s = kvm_state;
KVMSlot *mem = kvm_lookup_matching_slot(s, phys_addr, phys_addr + size);
int old_flags;
if (mem == NULL) {
fprintf(stderr, "BUG: %s: invalid parameters " TARGET_FMT_plx "-"
TARGET_FMT_plx "\n", __func__, phys_addr,
(target_phys_addr_t)(phys_addr + size - 1));
return -EINVAL;
}
old_flags = mem->flags;
flags = (mem->flags & ~mask) | flags;
mem->flags = flags;
/* If nothing changed effectively, no need to issue ioctl */
if (s->migration_log) {
flags |= KVM_MEM_LOG_DIRTY_PAGES;
}
if (flags == old_flags) {
return 0;
}
return kvm_set_user_memory_region(s, mem);
}
int kvm_log_start(target_phys_addr_t phys_addr, ram_addr_t size)
{
return kvm_dirty_pages_log_change(phys_addr, size,
KVM_MEM_LOG_DIRTY_PAGES,
KVM_MEM_LOG_DIRTY_PAGES);
}
int kvm_log_stop(target_phys_addr_t phys_addr, ram_addr_t size)
{
return kvm_dirty_pages_log_change(phys_addr, size,
0,
KVM_MEM_LOG_DIRTY_PAGES);
}
int kvm_set_migration_log(int enable)
{
KVMState *s = kvm_state;
KVMSlot *mem;
int i, err;
s->migration_log = enable;
for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
mem = &s->slots[i];
if (!!(mem->flags & KVM_MEM_LOG_DIRTY_PAGES) == enable) {
continue;
}
err = kvm_set_user_memory_region(s, mem);
if (err) {
return err;
}
}
return 0;
}
static int test_le_bit(unsigned long nr, unsigned char *addr)
{
return (addr[nr >> 3] >> (nr & 7)) & 1;
}
/**
* kvm_physical_sync_dirty_bitmap - Grab dirty bitmap from kernel space
* This function updates qemu's dirty bitmap using cpu_physical_memory_set_dirty().
* This means all bits are set to dirty.
*
* @start_add: start of logged region.
* @end_addr: end of logged region.
*/
int kvm_physical_sync_dirty_bitmap(target_phys_addr_t start_addr,
target_phys_addr_t end_addr)
{
KVMState *s = kvm_state;
unsigned long size, allocated_size = 0;
target_phys_addr_t phys_addr;
ram_addr_t addr;
KVMDirtyLog d;
KVMSlot *mem;
int ret = 0;
d.dirty_bitmap = NULL;
while (start_addr < end_addr) {
mem = kvm_lookup_overlapping_slot(s, start_addr, end_addr);
if (mem == NULL) {
break;
}
size = ((mem->memory_size >> TARGET_PAGE_BITS) + 7) / 8;
if (!d.dirty_bitmap) {
d.dirty_bitmap = qemu_malloc(size);
} else if (size > allocated_size) {
d.dirty_bitmap = qemu_realloc(d.dirty_bitmap, size);
}
allocated_size = size;
memset(d.dirty_bitmap, 0, allocated_size);
d.slot = mem->slot;
if (kvm_vm_ioctl(s, KVM_GET_DIRTY_LOG, &d) == -1) {
dprintf("ioctl failed %d\n", errno);
ret = -1;
break;
}
for (phys_addr = mem->start_addr, addr = mem->phys_offset;
phys_addr < mem->start_addr + mem->memory_size;
phys_addr += TARGET_PAGE_SIZE, addr += TARGET_PAGE_SIZE) {
unsigned char *bitmap = (unsigned char *)d.dirty_bitmap;
unsigned nr = (phys_addr - mem->start_addr) >> TARGET_PAGE_BITS;
if (test_le_bit(nr, bitmap)) {
cpu_physical_memory_set_dirty(addr);
}
}
start_addr = phys_addr;
}
qemu_free(d.dirty_bitmap);
return ret;
}
int kvm_coalesce_mmio_region(target_phys_addr_t start, ram_addr_t size)
{
int ret = -ENOSYS;
#ifdef KVM_CAP_COALESCED_MMIO
KVMState *s = kvm_state;
if (s->coalesced_mmio) {
struct kvm_coalesced_mmio_zone zone;
zone.addr = start;
zone.size = size;
ret = kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
}
#endif
return ret;
}
int kvm_uncoalesce_mmio_region(target_phys_addr_t start, ram_addr_t size)
{
int ret = -ENOSYS;
#ifdef KVM_CAP_COALESCED_MMIO
KVMState *s = kvm_state;
if (s->coalesced_mmio) {
struct kvm_coalesced_mmio_zone zone;
zone.addr = start;
zone.size = size;
ret = kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
}
#endif
return ret;
}
int kvm_check_extension(KVMState *s, unsigned int extension)
{
int ret;
ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, extension);
if (ret < 0) {
ret = 0;
}
return ret;
}
int kvm_init(int smp_cpus)
{
static const char upgrade_note[] =
"Please upgrade to at least kernel 2.6.29 or recent kvm-kmod\n"
"(see http://sourceforge.net/projects/kvm).\n";
KVMState *s;
int ret;
int i;
if (smp_cpus > 1) {
fprintf(stderr, "No SMP KVM support, use '-smp 1'\n");
return -EINVAL;
}
s = qemu_mallocz(sizeof(KVMState));
#ifdef KVM_CAP_SET_GUEST_DEBUG
QTAILQ_INIT(&s->kvm_sw_breakpoints);
#endif
for (i = 0; i < ARRAY_SIZE(s->slots); i++)
s->slots[i].slot = i;
s->vmfd = -1;
s->fd = qemu_open("/dev/kvm", O_RDWR);
if (s->fd == -1) {
fprintf(stderr, "Could not access KVM kernel module: %m\n");
ret = -errno;
goto err;
}
ret = kvm_ioctl(s, KVM_GET_API_VERSION, 0);
if (ret < KVM_API_VERSION) {
if (ret > 0)
ret = -EINVAL;
fprintf(stderr, "kvm version too old\n");
goto err;
}
if (ret > KVM_API_VERSION) {
ret = -EINVAL;
fprintf(stderr, "kvm version not supported\n");
goto err;
}
s->vmfd = kvm_ioctl(s, KVM_CREATE_VM, 0);
if (s->vmfd < 0)
goto err;
/* initially, KVM allocated its own memory and we had to jump through
* hooks to make phys_ram_base point to this. Modern versions of KVM
* just use a user allocated buffer so we can use regular pages
* unmodified. Make sure we have a sufficiently modern version of KVM.
*/
if (!kvm_check_extension(s, KVM_CAP_USER_MEMORY)) {
ret = -EINVAL;
fprintf(stderr, "kvm does not support KVM_CAP_USER_MEMORY\n%s",
upgrade_note);
goto err;
}
/* There was a nasty bug in < kvm-80 that prevents memory slots from being
* destroyed properly. Since we rely on this capability, refuse to work
* with any kernel without this capability. */
if (!kvm_check_extension(s, KVM_CAP_DESTROY_MEMORY_REGION_WORKS)) {
ret = -EINVAL;
fprintf(stderr,
"KVM kernel module broken (DESTROY_MEMORY_REGION).\n%s",
upgrade_note);
goto err;
}
s->coalesced_mmio = 0;
#ifdef KVM_CAP_COALESCED_MMIO
s->coalesced_mmio = kvm_check_extension(s, KVM_CAP_COALESCED_MMIO);
s->coalesced_mmio_ring = NULL;
#endif
s->broken_set_mem_region = 1;
#ifdef KVM_CAP_JOIN_MEMORY_REGIONS_WORKS
ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, KVM_CAP_JOIN_MEMORY_REGIONS_WORKS);
if (ret > 0) {
s->broken_set_mem_region = 0;
}
#endif
s->vcpu_events = 0;
#ifdef KVM_CAP_VCPU_EVENTS
s->vcpu_events = kvm_check_extension(s, KVM_CAP_VCPU_EVENTS);
#endif
ret = kvm_arch_init(s, smp_cpus);
if (ret < 0)
goto err;
kvm_state = s;
return 0;
err:
if (s) {
if (s->vmfd != -1)
close(s->vmfd);
if (s->fd != -1)
close(s->fd);
}
qemu_free(s);
return ret;
}
static int kvm_handle_io(uint16_t port, void *data, int direction, int size,
uint32_t count)
{
int i;
uint8_t *ptr = data;
for (i = 0; i < count; i++) {
if (direction == KVM_EXIT_IO_IN) {
switch (size) {
case 1:
stb_p(ptr, cpu_inb(port));
break;
case 2:
stw_p(ptr, cpu_inw(port));
break;
case 4:
stl_p(ptr, cpu_inl(port));
break;
}
} else {
switch (size) {
case 1:
cpu_outb(port, ldub_p(ptr));
break;
case 2:
cpu_outw(port, lduw_p(ptr));
break;
case 4:
cpu_outl(port, ldl_p(ptr));
break;
}
}
ptr += size;
}
return 1;
}
void kvm_flush_coalesced_mmio_buffer(void)
{
#ifdef KVM_CAP_COALESCED_MMIO
KVMState *s = kvm_state;
if (s->coalesced_mmio_ring) {
struct kvm_coalesced_mmio_ring *ring = s->coalesced_mmio_ring;
while (ring->first != ring->last) {
struct kvm_coalesced_mmio *ent;
ent = &ring->coalesced_mmio[ring->first];
cpu_physical_memory_write(ent->phys_addr, ent->data, ent->len);
/* FIXME smp_wmb() */
ring->first = (ring->first + 1) % KVM_COALESCED_MMIO_MAX;
}
}
#endif
}
void kvm_cpu_synchronize_state(CPUState *env)
{
if (!env->kvm_state->regs_modified) {
kvm_arch_get_registers(env);
env->kvm_state->regs_modified = 1;
}
}
int kvm_cpu_exec(CPUState *env)
{
struct kvm_run *run = env->kvm_run;
int ret;
dprintf("kvm_cpu_exec()\n");
do {
if (env->exit_request) {
dprintf("interrupt exit requested\n");
ret = 0;
break;
}
if (env->kvm_state->regs_modified) {
kvm_arch_put_registers(env);
env->kvm_state->regs_modified = 0;
}
kvm_arch_pre_run(env, run);
qemu_mutex_unlock_iothread();
ret = kvm_vcpu_ioctl(env, KVM_RUN, 0);
qemu_mutex_lock_iothread();
kvm_arch_post_run(env, run);
if (ret == -EINTR || ret == -EAGAIN) {
dprintf("io window exit\n");
ret = 0;
break;
}
if (ret < 0) {
dprintf("kvm run failed %s\n", strerror(-ret));
abort();
}
kvm_flush_coalesced_mmio_buffer();
ret = 0; /* exit loop */
switch (run->exit_reason) {
case KVM_EXIT_IO:
dprintf("handle_io\n");
ret = kvm_handle_io(run->io.port,
(uint8_t *)run + run->io.data_offset,
run->io.direction,
run->io.size,
run->io.count);
break;
case KVM_EXIT_MMIO:
dprintf("handle_mmio\n");
cpu_physical_memory_rw(run->mmio.phys_addr,
run->mmio.data,
run->mmio.len,
run->mmio.is_write);
ret = 1;
break;
case KVM_EXIT_IRQ_WINDOW_OPEN:
dprintf("irq_window_open\n");
break;
case KVM_EXIT_SHUTDOWN:
dprintf("shutdown\n");
qemu_system_reset_request();
ret = 1;
break;
case KVM_EXIT_UNKNOWN:
dprintf("kvm_exit_unknown\n");
break;
case KVM_EXIT_FAIL_ENTRY:
dprintf("kvm_exit_fail_entry\n");
break;
case KVM_EXIT_EXCEPTION:
dprintf("kvm_exit_exception\n");
break;
case KVM_EXIT_DEBUG:
dprintf("kvm_exit_debug\n");
#ifdef KVM_CAP_SET_GUEST_DEBUG
if (kvm_arch_debug(&run->debug.arch)) {
gdb_set_stop_cpu(env);
vm_stop(EXCP_DEBUG);
env->exception_index = EXCP_DEBUG;
return 0;
}
/* re-enter, this exception was guest-internal */
ret = 1;
#endif /* KVM_CAP_SET_GUEST_DEBUG */
break;
default:
dprintf("kvm_arch_handle_exit\n");
ret = kvm_arch_handle_exit(env, run);
break;
}
} while (ret > 0);
if (env->exit_request) {
env->exit_request = 0;
env->exception_index = EXCP_INTERRUPT;
}
return ret;
}
void kvm_set_phys_mem(target_phys_addr_t start_addr,
ram_addr_t size,
ram_addr_t phys_offset)
{
KVMState *s = kvm_state;
ram_addr_t flags = phys_offset & ~TARGET_PAGE_MASK;
KVMSlot *mem, old;
int err;
if (start_addr & ~TARGET_PAGE_MASK) {
if (flags >= IO_MEM_UNASSIGNED) {
if (!kvm_lookup_overlapping_slot(s, start_addr,
start_addr + size)) {
return;
}
fprintf(stderr, "Unaligned split of a KVM memory slot\n");
} else {
fprintf(stderr, "Only page-aligned memory slots supported\n");
}
abort();
}
/* KVM does not support read-only slots */
phys_offset &= ~IO_MEM_ROM;
while (1) {
mem = kvm_lookup_overlapping_slot(s, start_addr, start_addr + size);
if (!mem) {
break;
}
if (flags < IO_MEM_UNASSIGNED && start_addr >= mem->start_addr &&
(start_addr + size <= mem->start_addr + mem->memory_size) &&
(phys_offset - start_addr == mem->phys_offset - mem->start_addr)) {
/* The new slot fits into the existing one and comes with
* identical parameters - nothing to be done. */
return;
}
old = *mem;
/* unregister the overlapping slot */
mem->memory_size = 0;
err = kvm_set_user_memory_region(s, mem);
if (err) {
fprintf(stderr, "%s: error unregistering overlapping slot: %s\n",
__func__, strerror(-err));
abort();
}
/* Workaround for older KVM versions: we can't join slots, even not by
* unregistering the previous ones and then registering the larger
* slot. We have to maintain the existing fragmentation. Sigh.
*
* This workaround assumes that the new slot starts at the same
* address as the first existing one. If not or if some overlapping
* slot comes around later, we will fail (not seen in practice so far)
* - and actually require a recent KVM version. */
if (s->broken_set_mem_region &&
old.start_addr == start_addr && old.memory_size < size &&
flags < IO_MEM_UNASSIGNED) {
mem = kvm_alloc_slot(s);
mem->memory_size = old.memory_size;
mem->start_addr = old.start_addr;
mem->phys_offset = old.phys_offset;
mem->flags = 0;
err = kvm_set_user_memory_region(s, mem);
if (err) {
fprintf(stderr, "%s: error updating slot: %s\n", __func__,
strerror(-err));
abort();
}
start_addr += old.memory_size;
phys_offset += old.memory_size;
size -= old.memory_size;
continue;
}
/* register prefix slot */
if (old.start_addr < start_addr) {
mem = kvm_alloc_slot(s);
mem->memory_size = start_addr - old.start_addr;
mem->start_addr = old.start_addr;
mem->phys_offset = old.phys_offset;
mem->flags = 0;
err = kvm_set_user_memory_region(s, mem);
if (err) {
fprintf(stderr, "%s: error registering prefix slot: %s\n",
__func__, strerror(-err));
abort();
}
}
/* register suffix slot */
if (old.start_addr + old.memory_size > start_addr + size) {
ram_addr_t size_delta;
mem = kvm_alloc_slot(s);
mem->start_addr = start_addr + size;
size_delta = mem->start_addr - old.start_addr;
mem->memory_size = old.memory_size - size_delta;
mem->phys_offset = old.phys_offset + size_delta;
mem->flags = 0;
err = kvm_set_user_memory_region(s, mem);
if (err) {
fprintf(stderr, "%s: error registering suffix slot: %s\n",
__func__, strerror(-err));
abort();
}
}
}
/* in case the KVM bug workaround already "consumed" the new slot */
if (!size)
return;
/* KVM does not need to know about this memory */
if (flags >= IO_MEM_UNASSIGNED)
return;
mem = kvm_alloc_slot(s);
mem->memory_size = size;
mem->start_addr = start_addr;
mem->phys_offset = phys_offset;
mem->flags = 0;
err = kvm_set_user_memory_region(s, mem);
if (err) {
fprintf(stderr, "%s: error registering slot: %s\n", __func__,
strerror(-err));
abort();
}
}
int kvm_ioctl(KVMState *s, int type, ...)
{
int ret;
void *arg;
va_list ap;
va_start(ap, type);
arg = va_arg(ap, void *);
va_end(ap);
ret = ioctl(s->fd, type, arg);
if (ret == -1)
ret = -errno;
return ret;
}
int kvm_vm_ioctl(KVMState *s, int type, ...)
{
int ret;
void *arg;
va_list ap;
va_start(ap, type);
arg = va_arg(ap, void *);
va_end(ap);
ret = ioctl(s->vmfd, type, arg);
if (ret == -1)
ret = -errno;
return ret;
}
int kvm_vcpu_ioctl(CPUState *env, int type, ...)
{
int ret;
void *arg;
va_list ap;
va_start(ap, type);
arg = va_arg(ap, void *);
va_end(ap);
ret = ioctl(env->kvm_fd, type, arg);
if (ret == -1)
ret = -errno;
return ret;
}
int kvm_has_sync_mmu(void)
{
#ifdef KVM_CAP_SYNC_MMU
KVMState *s = kvm_state;
return kvm_check_extension(s, KVM_CAP_SYNC_MMU);
#else
return 0;
#endif
}
int kvm_has_vcpu_events(void)
{
return kvm_state->vcpu_events;
}
void kvm_setup_guest_memory(void *start, size_t size)
{
if (!kvm_has_sync_mmu()) {
#ifdef MADV_DONTFORK
int ret = madvise(start, size, MADV_DONTFORK);
if (ret) {
perror("madvice");
exit(1);
}
#else
fprintf(stderr,
"Need MADV_DONTFORK in absence of synchronous KVM MMU\n");
exit(1);
#endif
}
}
#ifdef KVM_CAP_SET_GUEST_DEBUG
static void on_vcpu(CPUState *env, void (*func)(void *data), void *data)
{
#ifdef CONFIG_IOTHREAD
if (env == cpu_single_env) {
func(data);
return;
}
abort();
#else
func(data);
#endif
}
struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *env,
target_ulong pc)
{
struct kvm_sw_breakpoint *bp;
QTAILQ_FOREACH(bp, &env->kvm_state->kvm_sw_breakpoints, entry) {
if (bp->pc == pc)
return bp;
}
return NULL;
}
int kvm_sw_breakpoints_active(CPUState *env)
{
return !QTAILQ_EMPTY(&env->kvm_state->kvm_sw_breakpoints);
}
struct kvm_set_guest_debug_data {
struct kvm_guest_debug dbg;
CPUState *env;
int err;
};
static void kvm_invoke_set_guest_debug(void *data)
{
struct kvm_set_guest_debug_data *dbg_data = data;
CPUState *env = dbg_data->env;
if (env->kvm_state->regs_modified) {
kvm_arch_put_registers(env);
env->kvm_state->regs_modified = 0;
}
dbg_data->err = kvm_vcpu_ioctl(env, KVM_SET_GUEST_DEBUG, &dbg_data->dbg);
}
int kvm_update_guest_debug(CPUState *env, unsigned long reinject_trap)
{
struct kvm_set_guest_debug_data data;
data.dbg.control = 0;
if (env->singlestep_enabled)
data.dbg.control = KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP;
kvm_arch_update_guest_debug(env, &data.dbg);
data.dbg.control |= reinject_trap;
data.env = env;
on_vcpu(env, kvm_invoke_set_guest_debug, &data);
return data.err;
}
int kvm_insert_breakpoint(CPUState *current_env, target_ulong addr,
target_ulong len, int type)
{
struct kvm_sw_breakpoint *bp;
CPUState *env;
int err;
if (type == GDB_BREAKPOINT_SW) {
bp = kvm_find_sw_breakpoint(current_env, addr);
if (bp) {
bp->use_count++;
return 0;
}
bp = qemu_malloc(sizeof(struct kvm_sw_breakpoint));
if (!bp)
return -ENOMEM;
bp->pc = addr;
bp->use_count = 1;
err = kvm_arch_insert_sw_breakpoint(current_env, bp);
if (err) {
free(bp);
return err;
}
QTAILQ_INSERT_HEAD(&current_env->kvm_state->kvm_sw_breakpoints,
bp, entry);
} else {
err = kvm_arch_insert_hw_breakpoint(addr, len, type);
if (err)
return err;
}
for (env = first_cpu; env != NULL; env = env->next_cpu) {
err = kvm_update_guest_debug(env, 0);
if (err)
return err;
}
return 0;
}
int kvm_remove_breakpoint(CPUState *current_env, target_ulong addr,
target_ulong len, int type)
{
struct kvm_sw_breakpoint *bp;
CPUState *env;
int err;
if (type == GDB_BREAKPOINT_SW) {
bp = kvm_find_sw_breakpoint(current_env, addr);
if (!bp)
return -ENOENT;
if (bp->use_count > 1) {
bp->use_count--;
return 0;
}
err = kvm_arch_remove_sw_breakpoint(current_env, bp);
if (err)
return err;
QTAILQ_REMOVE(&current_env->kvm_state->kvm_sw_breakpoints, bp, entry);
qemu_free(bp);
} else {
err = kvm_arch_remove_hw_breakpoint(addr, len, type);
if (err)
return err;
}
for (env = first_cpu; env != NULL; env = env->next_cpu) {
err = kvm_update_guest_debug(env, 0);
if (err)
return err;
}
return 0;
}
void kvm_remove_all_breakpoints(CPUState *current_env)
{
struct kvm_sw_breakpoint *bp, *next;
KVMState *s = current_env->kvm_state;
CPUState *env;
QTAILQ_FOREACH_SAFE(bp, &s->kvm_sw_breakpoints, entry, next) {
if (kvm_arch_remove_sw_breakpoint(current_env, bp) != 0) {
/* Try harder to find a CPU that currently sees the breakpoint. */
for (env = first_cpu; env != NULL; env = env->next_cpu) {
if (kvm_arch_remove_sw_breakpoint(env, bp) == 0)
break;
}
}
}
kvm_arch_remove_all_hw_breakpoints();
for (env = first_cpu; env != NULL; env = env->next_cpu)
kvm_update_guest_debug(env, 0);
}
#else /* !KVM_CAP_SET_GUEST_DEBUG */
int kvm_update_guest_debug(CPUState *env, unsigned long reinject_trap)
{
return -EINVAL;
}
int kvm_insert_breakpoint(CPUState *current_env, target_ulong addr,
target_ulong len, int type)
{
return -EINVAL;
}
int kvm_remove_breakpoint(CPUState *current_env, target_ulong addr,
target_ulong len, int type)
{
return -EINVAL;
}
void kvm_remove_all_breakpoints(CPUState *current_env)
{
}
#endif /* !KVM_CAP_SET_GUEST_DEBUG */
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