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qemu / qemu / eff3de52f265df39c6fc668415ad317ec1f24051 / . / accel / kvm / kvm-all.c
blob: f99b0becd887932e1bb0e80ad4ef29d55452c081 [file] [log] [blame]
/*
* 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 "qemu/osdep.h"
#include <sys/ioctl.h>
#include <poll.h>
#include <linux/kvm.h>
#include "qemu/atomic.h"
#include "qemu/option.h"
#include "qemu/config-file.h"
#include "qemu/error-report.h"
#include "qapi/error.h"
#include "hw/pci/msi.h"
#include "hw/pci/msix.h"
#include "hw/s390x/adapter.h"
#include "exec/gdbstub.h"
#include "sysemu/kvm_int.h"
#include "sysemu/runstate.h"
#include "sysemu/cpus.h"
#include "qemu/bswap.h"
#include "exec/memory.h"
#include "exec/ram_addr.h"
#include "qemu/event_notifier.h"
#include "qemu/main-loop.h"
#include "trace.h"
#include "hw/irq.h"
#include "qapi/visitor.h"
#include "qapi/qapi-types-common.h"
#include "qapi/qapi-visit-common.h"
#include "sysemu/reset.h"
#include "qemu/guest-random.h"
#include "sysemu/hw_accel.h"
#include "kvm-cpus.h"
#include "sysemu/dirtylimit.h"
#include "hw/boards.h"
#include "monitor/stats.h"
/* This check must be after config-host.h is included */
#ifdef CONFIG_EVENTFD
#include <sys/eventfd.h>
#endif
/* KVM uses PAGE_SIZE in its definition of KVM_COALESCED_MMIO_MAX. We
* need to use the real host PAGE_SIZE, as that's what KVM will use.
*/
#ifdef PAGE_SIZE
#undef PAGE_SIZE
#endif
#define PAGE_SIZE qemu_real_host_page_size()
#ifndef KVM_GUESTDBG_BLOCKIRQ
#define KVM_GUESTDBG_BLOCKIRQ 0
#endif
//#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
struct KVMParkedVcpu {
unsigned long vcpu_id;
int kvm_fd;
QLIST_ENTRY(KVMParkedVcpu) node;
};
KVMState *kvm_state;
bool kvm_kernel_irqchip;
bool kvm_split_irqchip;
bool kvm_async_interrupts_allowed;
bool kvm_halt_in_kernel_allowed;
bool kvm_eventfds_allowed;
bool kvm_irqfds_allowed;
bool kvm_resamplefds_allowed;
bool kvm_msi_via_irqfd_allowed;
bool kvm_gsi_routing_allowed;
bool kvm_gsi_direct_mapping;
bool kvm_allowed;
bool kvm_readonly_mem_allowed;
bool kvm_vm_attributes_allowed;
bool kvm_direct_msi_allowed;
bool kvm_ioeventfd_any_length_allowed;
bool kvm_msi_use_devid;
bool kvm_has_guest_debug;
static int kvm_sstep_flags;
static bool kvm_immediate_exit;
static hwaddr kvm_max_slot_size = ~0;
static const KVMCapabilityInfo kvm_required_capabilites[] = {
KVM_CAP_INFO(USER_MEMORY),
KVM_CAP_INFO(DESTROY_MEMORY_REGION_WORKS),
KVM_CAP_INFO(JOIN_MEMORY_REGIONS_WORKS),
KVM_CAP_LAST_INFO
};
static NotifierList kvm_irqchip_change_notifiers =
NOTIFIER_LIST_INITIALIZER(kvm_irqchip_change_notifiers);
struct KVMResampleFd {
int gsi;
EventNotifier *resample_event;
QLIST_ENTRY(KVMResampleFd) node;
};
typedef struct KVMResampleFd KVMResampleFd;
/*
* Only used with split irqchip where we need to do the resample fd
* kick for the kernel from userspace.
*/
static QLIST_HEAD(, KVMResampleFd) kvm_resample_fd_list =
QLIST_HEAD_INITIALIZER(kvm_resample_fd_list);
static QemuMutex kml_slots_lock;
#define kvm_slots_lock() qemu_mutex_lock(&kml_slots_lock)
#define kvm_slots_unlock() qemu_mutex_unlock(&kml_slots_lock)
static void kvm_slot_init_dirty_bitmap(KVMSlot *mem);
static inline void kvm_resample_fd_remove(int gsi)
{
KVMResampleFd *rfd;
QLIST_FOREACH(rfd, &kvm_resample_fd_list, node) {
if (rfd->gsi == gsi) {
QLIST_REMOVE(rfd, node);
g_free(rfd);
break;
}
}
}
static inline void kvm_resample_fd_insert(int gsi, EventNotifier *event)
{
KVMResampleFd *rfd = g_new0(KVMResampleFd, 1);
rfd->gsi = gsi;
rfd->resample_event = event;
QLIST_INSERT_HEAD(&kvm_resample_fd_list, rfd, node);
}
void kvm_resample_fd_notify(int gsi)
{
KVMResampleFd *rfd;
QLIST_FOREACH(rfd, &kvm_resample_fd_list, node) {
if (rfd->gsi == gsi) {
event_notifier_set(rfd->resample_event);
trace_kvm_resample_fd_notify(gsi);
return;
}
}
}
int kvm_get_max_memslots(void)
{
KVMState *s = KVM_STATE(current_accel());
return s->nr_slots;
}
/* Called with KVMMemoryListener.slots_lock held */
static KVMSlot *kvm_get_free_slot(KVMMemoryListener *kml)
{
KVMState *s = kvm_state;
int i;
for (i = 0; i < s->nr_slots; i++) {
if (kml->slots[i].memory_size == 0) {
return &kml->slots[i];
}
}
return NULL;
}
bool kvm_has_free_slot(MachineState *ms)
{
KVMState *s = KVM_STATE(ms->accelerator);
bool result;
KVMMemoryListener *kml = &s->memory_listener;
kvm_slots_lock();
result = !!kvm_get_free_slot(kml);
kvm_slots_unlock();
return result;
}
/* Called with KVMMemoryListener.slots_lock held */
static KVMSlot *kvm_alloc_slot(KVMMemoryListener *kml)
{
KVMSlot *slot = kvm_get_free_slot(kml);
if (slot) {
return slot;
}
fprintf(stderr, "%s: no free slot available\n", __func__);
abort();
}
static KVMSlot *kvm_lookup_matching_slot(KVMMemoryListener *kml,
hwaddr start_addr,
hwaddr size)
{
KVMState *s = kvm_state;
int i;
for (i = 0; i < s->nr_slots; i++) {
KVMSlot *mem = &kml->slots[i];
if (start_addr == mem->start_addr && size == mem->memory_size) {
return mem;
}
}
return NULL;
}
/*
* Calculate and align the start address and the size of the section.
* Return the size. If the size is 0, the aligned section is empty.
*/
static hwaddr kvm_align_section(MemoryRegionSection *section,
hwaddr *start)
{
hwaddr size = int128_get64(section->size);
hwaddr delta, aligned;
/* kvm works in page size chunks, but the function may be called
with sub-page size and unaligned start address. Pad the start
address to next and truncate size to previous page boundary. */
aligned = ROUND_UP(section->offset_within_address_space,
qemu_real_host_page_size());
delta = aligned - section->offset_within_address_space;
*start = aligned;
if (delta > size) {
return 0;
}
return (size - delta) & qemu_real_host_page_mask();
}
int kvm_physical_memory_addr_from_host(KVMState *s, void *ram,
hwaddr *phys_addr)
{
KVMMemoryListener *kml = &s->memory_listener;
int i, ret = 0;
kvm_slots_lock();
for (i = 0; i < s->nr_slots; i++) {
KVMSlot *mem = &kml->slots[i];
if (ram >= mem->ram && ram < mem->ram + mem->memory_size) {
*phys_addr = mem->start_addr + (ram - mem->ram);
ret = 1;
break;
}
}
kvm_slots_unlock();
return ret;
}
static int kvm_set_user_memory_region(KVMMemoryListener *kml, KVMSlot *slot, bool new)
{
KVMState *s = kvm_state;
struct kvm_userspace_memory_region mem;
int ret;
mem.slot = slot->slot | (kml->as_id << 16);
mem.guest_phys_addr = slot->start_addr;
mem.userspace_addr = (unsigned long)slot->ram;
mem.flags = slot->flags;
if (slot->memory_size && !new && (mem.flags ^ slot->old_flags) & KVM_MEM_READONLY) {
/* Set the slot size to 0 before setting the slot to the desired
* value. This is needed based on KVM commit 75d61fbc. */
mem.memory_size = 0;
ret = kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, &mem);
if (ret < 0) {
goto err;
}
}
mem.memory_size = slot->memory_size;
ret = kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, &mem);
slot->old_flags = mem.flags;
err:
trace_kvm_set_user_memory(mem.slot, mem.flags, mem.guest_phys_addr,
mem.memory_size, mem.userspace_addr, ret);
if (ret < 0) {
error_report("%s: KVM_SET_USER_MEMORY_REGION failed, slot=%d,"
" start=0x%" PRIx64 ", size=0x%" PRIx64 ": %s",
__func__, mem.slot, slot->start_addr,
(uint64_t)mem.memory_size, strerror(errno));
}
return ret;
}
static int do_kvm_destroy_vcpu(CPUState *cpu)
{
KVMState *s = kvm_state;
long mmap_size;
struct KVMParkedVcpu *vcpu = NULL;
int ret = 0;
DPRINTF("kvm_destroy_vcpu\n");
ret = kvm_arch_destroy_vcpu(cpu);
if (ret < 0) {
goto err;
}
mmap_size = kvm_ioctl(s, KVM_GET_VCPU_MMAP_SIZE, 0);
if (mmap_size < 0) {
ret = mmap_size;
DPRINTF("KVM_GET_VCPU_MMAP_SIZE failed\n");
goto err;
}
ret = munmap(cpu->kvm_run, mmap_size);
if (ret < 0) {
goto err;
}
if (cpu->kvm_dirty_gfns) {
ret = munmap(cpu->kvm_dirty_gfns, s->kvm_dirty_ring_bytes);
if (ret < 0) {
goto err;
}
}
vcpu = g_malloc0(sizeof(*vcpu));
vcpu->vcpu_id = kvm_arch_vcpu_id(cpu);
vcpu->kvm_fd = cpu->kvm_fd;
QLIST_INSERT_HEAD(&kvm_state->kvm_parked_vcpus, vcpu, node);
err:
return ret;
}
void kvm_destroy_vcpu(CPUState *cpu)
{
if (do_kvm_destroy_vcpu(cpu) < 0) {
error_report("kvm_destroy_vcpu failed");
exit(EXIT_FAILURE);
}
}
static int kvm_get_vcpu(KVMState *s, unsigned long vcpu_id)
{
struct KVMParkedVcpu *cpu;
QLIST_FOREACH(cpu, &s->kvm_parked_vcpus, node) {
if (cpu->vcpu_id == vcpu_id) {
int kvm_fd;
QLIST_REMOVE(cpu, node);
kvm_fd = cpu->kvm_fd;
g_free(cpu);
return kvm_fd;
}
}
return kvm_vm_ioctl(s, KVM_CREATE_VCPU, (void *)vcpu_id);
}
int kvm_init_vcpu(CPUState *cpu, Error **errp)
{
KVMState *s = kvm_state;
long mmap_size;
int ret;
trace_kvm_init_vcpu(cpu->cpu_index, kvm_arch_vcpu_id(cpu));
ret = kvm_get_vcpu(s, kvm_arch_vcpu_id(cpu));
if (ret < 0) {
error_setg_errno(errp, -ret, "kvm_init_vcpu: kvm_get_vcpu failed (%lu)",
kvm_arch_vcpu_id(cpu));
goto err;
}
cpu->kvm_fd = ret;
cpu->kvm_state = s;
cpu->vcpu_dirty = true;
cpu->dirty_pages = 0;
cpu->throttle_us_per_full = 0;
mmap_size = kvm_ioctl(s, KVM_GET_VCPU_MMAP_SIZE, 0);
if (mmap_size < 0) {
ret = mmap_size;
error_setg_errno(errp, -mmap_size,
"kvm_init_vcpu: KVM_GET_VCPU_MMAP_SIZE failed");
goto err;
}
cpu->kvm_run = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED,
cpu->kvm_fd, 0);
if (cpu->kvm_run == MAP_FAILED) {
ret = -errno;
error_setg_errno(errp, ret,
"kvm_init_vcpu: mmap'ing vcpu state failed (%lu)",
kvm_arch_vcpu_id(cpu));
goto err;
}
if (s->coalesced_mmio && !s->coalesced_mmio_ring) {
s->coalesced_mmio_ring =
(void *)cpu->kvm_run + s->coalesced_mmio * PAGE_SIZE;
}
if (s->kvm_dirty_ring_size) {
/* Use MAP_SHARED to share pages with the kernel */
cpu->kvm_dirty_gfns = mmap(NULL, s->kvm_dirty_ring_bytes,
PROT_READ | PROT_WRITE, MAP_SHARED,
cpu->kvm_fd,
PAGE_SIZE * KVM_DIRTY_LOG_PAGE_OFFSET);
if (cpu->kvm_dirty_gfns == MAP_FAILED) {
ret = -errno;
DPRINTF("mmap'ing vcpu dirty gfns failed: %d\n", ret);
goto err;
}
}
ret = kvm_arch_init_vcpu(cpu);
if (ret < 0) {
error_setg_errno(errp, -ret,
"kvm_init_vcpu: kvm_arch_init_vcpu failed (%lu)",
kvm_arch_vcpu_id(cpu));
}
err:
return ret;
}
/*
* dirty pages logging control
*/
static int kvm_mem_flags(MemoryRegion *mr)
{
bool readonly = mr->readonly || memory_region_is_romd(mr);
int flags = 0;
if (memory_region_get_dirty_log_mask(mr) != 0) {
flags |= KVM_MEM_LOG_DIRTY_PAGES;
}
if (readonly && kvm_readonly_mem_allowed) {
flags |= KVM_MEM_READONLY;
}
return flags;
}
/* Called with KVMMemoryListener.slots_lock held */
static int kvm_slot_update_flags(KVMMemoryListener *kml, KVMSlot *mem,
MemoryRegion *mr)
{
mem->flags = kvm_mem_flags(mr);
/* If nothing changed effectively, no need to issue ioctl */
if (mem->flags == mem->old_flags) {
return 0;
}
kvm_slot_init_dirty_bitmap(mem);
return kvm_set_user_memory_region(kml, mem, false);
}
static int kvm_section_update_flags(KVMMemoryListener *kml,
MemoryRegionSection *section)
{
hwaddr start_addr, size, slot_size;
KVMSlot *mem;
int ret = 0;
size = kvm_align_section(section, &start_addr);
if (!size) {
return 0;
}
kvm_slots_lock();
while (size && !ret) {
slot_size = MIN(kvm_max_slot_size, size);
mem = kvm_lookup_matching_slot(kml, start_addr, slot_size);
if (!mem) {
/* We don't have a slot if we want to trap every access. */
goto out;
}
ret = kvm_slot_update_flags(kml, mem, section->mr);
start_addr += slot_size;
size -= slot_size;
}
out:
kvm_slots_unlock();
return ret;
}
static void kvm_log_start(MemoryListener *listener,
MemoryRegionSection *section,
int old, int new)
{
KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
int r;
if (old != 0) {
return;
}
r = kvm_section_update_flags(kml, section);
if (r < 0) {
abort();
}
}
static void kvm_log_stop(MemoryListener *listener,
MemoryRegionSection *section,
int old, int new)
{
KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
int r;
if (new != 0) {
return;
}
r = kvm_section_update_flags(kml, section);
if (r < 0) {
abort();
}
}
/* get kvm's dirty pages bitmap and update qemu's */
static void kvm_slot_sync_dirty_pages(KVMSlot *slot)
{
ram_addr_t start = slot->ram_start_offset;
ram_addr_t pages = slot->memory_size / qemu_real_host_page_size();
cpu_physical_memory_set_dirty_lebitmap(slot->dirty_bmap, start, pages);
}
static void kvm_slot_reset_dirty_pages(KVMSlot *slot)
{
memset(slot->dirty_bmap, 0, slot->dirty_bmap_size);
}
#define ALIGN(x, y) (((x)+(y)-1) & ~((y)-1))
/* Allocate the dirty bitmap for a slot */
static void kvm_slot_init_dirty_bitmap(KVMSlot *mem)
{
if (!(mem->flags & KVM_MEM_LOG_DIRTY_PAGES) || mem->dirty_bmap) {
return;
}
/*
* XXX bad kernel interface alert
* For dirty bitmap, kernel allocates array of size aligned to
* bits-per-long. But for case when the kernel is 64bits and
* the userspace is 32bits, userspace can't align to the same
* bits-per-long, since sizeof(long) is different between kernel
* and user space. This way, userspace will provide buffer which
* may be 4 bytes less than the kernel will use, resulting in
* userspace memory corruption (which is not detectable by valgrind
* too, in most cases).
* So for now, let's align to 64 instead of HOST_LONG_BITS here, in
* a hope that sizeof(long) won't become >8 any time soon.
*
* Note: the granule of kvm dirty log is qemu_real_host_page_size.
* And mem->memory_size is aligned to it (otherwise this mem can't
* be registered to KVM).
*/
hwaddr bitmap_size = ALIGN(mem->memory_size / qemu_real_host_page_size(),
/*HOST_LONG_BITS*/ 64) / 8;
mem->dirty_bmap = g_malloc0(bitmap_size);
mem->dirty_bmap_size = bitmap_size;
}
/*
* Sync dirty bitmap from kernel to KVMSlot.dirty_bmap, return true if
* succeeded, false otherwise
*/
static bool kvm_slot_get_dirty_log(KVMState *s, KVMSlot *slot)
{
struct kvm_dirty_log d = {};
int ret;
d.dirty_bitmap = slot->dirty_bmap;
d.slot = slot->slot | (slot->as_id << 16);
ret = kvm_vm_ioctl(s, KVM_GET_DIRTY_LOG, &d);
if (ret == -ENOENT) {
/* kernel does not have dirty bitmap in this slot */
ret = 0;
}
if (ret) {
error_report_once("%s: KVM_GET_DIRTY_LOG failed with %d",
__func__, ret);
}
return ret == 0;
}
/* Should be with all slots_lock held for the address spaces. */
static void kvm_dirty_ring_mark_page(KVMState *s, uint32_t as_id,
uint32_t slot_id, uint64_t offset)
{
KVMMemoryListener *kml;
KVMSlot *mem;
if (as_id >= s->nr_as) {
return;
}
kml = s->as[as_id].ml;
mem = &kml->slots[slot_id];
if (!mem->memory_size || offset >=
(mem->memory_size / qemu_real_host_page_size())) {
return;
}
set_bit(offset, mem->dirty_bmap);
}
static bool dirty_gfn_is_dirtied(struct kvm_dirty_gfn *gfn)
{
/*
* Read the flags before the value. Pairs with barrier in
* KVM's kvm_dirty_ring_push() function.
*/
return qatomic_load_acquire(&gfn->flags) == KVM_DIRTY_GFN_F_DIRTY;
}
static void dirty_gfn_set_collected(struct kvm_dirty_gfn *gfn)
{
/*
* Use a store-release so that the CPU that executes KVM_RESET_DIRTY_RINGS
* sees the full content of the ring:
*
* CPU0 CPU1 CPU2
* ------------------------------------------------------------------------------
* fill gfn0
* store-rel flags for gfn0
* load-acq flags for gfn0
* store-rel RESET for gfn0
* ioctl(RESET_RINGS)
* load-acq flags for gfn0
* check if flags have RESET
*
* The synchronization goes from CPU2 to CPU0 to CPU1.
*/
qatomic_store_release(&gfn->flags, KVM_DIRTY_GFN_F_RESET);
}
/*
* Should be with all slots_lock held for the address spaces. It returns the
* dirty page we've collected on this dirty ring.
*/
static uint32_t kvm_dirty_ring_reap_one(KVMState *s, CPUState *cpu)
{
struct kvm_dirty_gfn *dirty_gfns = cpu->kvm_dirty_gfns, *cur;
uint32_t ring_size = s->kvm_dirty_ring_size;
uint32_t count = 0, fetch = cpu->kvm_fetch_index;
assert(dirty_gfns && ring_size);
trace_kvm_dirty_ring_reap_vcpu(cpu->cpu_index);
while (true) {
cur = &dirty_gfns[fetch % ring_size];
if (!dirty_gfn_is_dirtied(cur)) {
break;
}
kvm_dirty_ring_mark_page(s, cur->slot >> 16, cur->slot & 0xffff,
cur->offset);
dirty_gfn_set_collected(cur);
trace_kvm_dirty_ring_page(cpu->cpu_index, fetch, cur->offset);
fetch++;
count++;
}
cpu->kvm_fetch_index = fetch;
cpu->dirty_pages += count;
return count;
}
/* Must be with slots_lock held */
static uint64_t kvm_dirty_ring_reap_locked(KVMState *s, CPUState* cpu)
{
int ret;
uint64_t total = 0;
int64_t stamp;
stamp = get_clock();
if (cpu) {
total = kvm_dirty_ring_reap_one(s, cpu);
} else {
CPU_FOREACH(cpu) {
total += kvm_dirty_ring_reap_one(s, cpu);
}
}
if (total) {
ret = kvm_vm_ioctl(s, KVM_RESET_DIRTY_RINGS);
assert(ret == total);
}
stamp = get_clock() - stamp;
if (total) {
trace_kvm_dirty_ring_reap(total, stamp / 1000);
}
return total;
}
/*
* Currently for simplicity, we must hold BQL before calling this. We can
* consider to drop the BQL if we're clear with all the race conditions.
*/
static uint64_t kvm_dirty_ring_reap(KVMState *s, CPUState *cpu)
{
uint64_t total;
/*
* We need to lock all kvm slots for all address spaces here,
* because:
*
* (1) We need to mark dirty for dirty bitmaps in multiple slots
* and for tons of pages, so it's better to take the lock here
* once rather than once per page. And more importantly,
*
* (2) We must _NOT_ publish dirty bits to the other threads
* (e.g., the migration thread) via the kvm memory slot dirty
* bitmaps before correctly re-protect those dirtied pages.
* Otherwise we can have potential risk of data corruption if
* the page data is read in the other thread before we do
* reset below.
*/
kvm_slots_lock();
total = kvm_dirty_ring_reap_locked(s, cpu);
kvm_slots_unlock();
return total;
}
static void do_kvm_cpu_synchronize_kick(CPUState *cpu, run_on_cpu_data arg)
{
/* No need to do anything */
}
/*
* Kick all vcpus out in a synchronized way. When returned, we
* guarantee that every vcpu has been kicked and at least returned to
* userspace once.
*/
static void kvm_cpu_synchronize_kick_all(void)
{
CPUState *cpu;
CPU_FOREACH(cpu) {
run_on_cpu(cpu, do_kvm_cpu_synchronize_kick, RUN_ON_CPU_NULL);
}
}
/*
* Flush all the existing dirty pages to the KVM slot buffers. When
* this call returns, we guarantee that all the touched dirty pages
* before calling this function have been put into the per-kvmslot
* dirty bitmap.
*
* This function must be called with BQL held.
*/
static void kvm_dirty_ring_flush(void)
{
trace_kvm_dirty_ring_flush(0);
/*
* The function needs to be serialized. Since this function
* should always be with BQL held, serialization is guaranteed.
* However, let's be sure of it.
*/
assert(qemu_mutex_iothread_locked());
/*
* First make sure to flush the hardware buffers by kicking all
* vcpus out in a synchronous way.
*/
kvm_cpu_synchronize_kick_all();
kvm_dirty_ring_reap(kvm_state, NULL);
trace_kvm_dirty_ring_flush(1);
}
/**
* kvm_physical_sync_dirty_bitmap - Sync dirty bitmap from kernel space
*
* This function will first try to fetch dirty bitmap from the kernel,
* and then updates qemu's dirty bitmap.
*
* NOTE: caller must be with kml->slots_lock held.
*
* @kml: the KVM memory listener object
* @section: the memory section to sync the dirty bitmap with
*/
static void kvm_physical_sync_dirty_bitmap(KVMMemoryListener *kml,
MemoryRegionSection *section)
{
KVMState *s = kvm_state;
KVMSlot *mem;
hwaddr start_addr, size;
hwaddr slot_size;
size = kvm_align_section(section, &start_addr);
while (size) {
slot_size = MIN(kvm_max_slot_size, size);
mem = kvm_lookup_matching_slot(kml, start_addr, slot_size);
if (!mem) {
/* We don't have a slot if we want to trap every access. */
return;
}
if (kvm_slot_get_dirty_log(s, mem)) {
kvm_slot_sync_dirty_pages(mem);
}
start_addr += slot_size;
size -= slot_size;
}
}
/* Alignment requirement for KVM_CLEAR_DIRTY_LOG - 64 pages */
#define KVM_CLEAR_LOG_SHIFT 6
#define KVM_CLEAR_LOG_ALIGN (qemu_real_host_page_size() << KVM_CLEAR_LOG_SHIFT)
#define KVM_CLEAR_LOG_MASK (-KVM_CLEAR_LOG_ALIGN)
static int kvm_log_clear_one_slot(KVMSlot *mem, int as_id, uint64_t start,
uint64_t size)
{
KVMState *s = kvm_state;
uint64_t end, bmap_start, start_delta, bmap_npages;
struct kvm_clear_dirty_log d;
unsigned long *bmap_clear = NULL, psize = qemu_real_host_page_size();
int ret;
/*
* We need to extend either the start or the size or both to
* satisfy the KVM interface requirement. Firstly, do the start
* page alignment on 64 host pages
*/
bmap_start = start & KVM_CLEAR_LOG_MASK;
start_delta = start - bmap_start;
bmap_start /= psize;
/*
* The kernel interface has restriction on the size too, that either:
*
* (1) the size is 64 host pages aligned (just like the start), or
* (2) the size fills up until the end of the KVM memslot.
*/
bmap_npages = DIV_ROUND_UP(size + start_delta, KVM_CLEAR_LOG_ALIGN)
<< KVM_CLEAR_LOG_SHIFT;
end = mem->memory_size / psize;
if (bmap_npages > end - bmap_start) {
bmap_npages = end - bmap_start;
}
start_delta /= psize;
/*
* Prepare the bitmap to clear dirty bits. Here we must guarantee
* that we won't clear any unknown dirty bits otherwise we might
* accidentally clear some set bits which are not yet synced from
* the kernel into QEMU's bitmap, then we'll lose track of the
* guest modifications upon those pages (which can directly lead
* to guest data loss or panic after migration).
*
* Layout of the KVMSlot.dirty_bmap:
*
* |<-------- bmap_npages -----------..>|
* [1]
* start_delta size
* |----------------|-------------|------------------|------------|
* ^ ^ ^ ^
* | | | |
* start bmap_start (start) end
* of memslot of memslot
*
* [1] bmap_npages can be aligned to either 64 pages or the end of slot
*/
assert(bmap_start % BITS_PER_LONG == 0);
/* We should never do log_clear before log_sync */
assert(mem->dirty_bmap);
if (start_delta || bmap_npages - size / psize) {
/* Slow path - we need to manipulate a temp bitmap */
bmap_clear = bitmap_new(bmap_npages);
bitmap_copy_with_src_offset(bmap_clear, mem->dirty_bmap,
bmap_start, start_delta + size / psize);
/*
* We need to fill the holes at start because that was not
* specified by the caller and we extended the bitmap only for
* 64 pages alignment
*/
bitmap_clear(bmap_clear, 0, start_delta);
d.dirty_bitmap = bmap_clear;
} else {
/*
* Fast path - both start and size align well with BITS_PER_LONG
* (or the end of memory slot)
*/
d.dirty_bitmap = mem->dirty_bmap + BIT_WORD(bmap_start);
}
d.first_page = bmap_start;
/* It should never overflow. If it happens, say something */
assert(bmap_npages <= UINT32_MAX);
d.num_pages = bmap_npages;
d.slot = mem->slot | (as_id << 16);
ret = kvm_vm_ioctl(s, KVM_CLEAR_DIRTY_LOG, &d);
if (ret < 0 && ret != -ENOENT) {
error_report("%s: KVM_CLEAR_DIRTY_LOG failed, slot=%d, "
"start=0x%"PRIx64", size=0x%"PRIx32", errno=%d",
__func__, d.slot, (uint64_t)d.first_page,
(uint32_t)d.num_pages, ret);
} else {
ret = 0;
trace_kvm_clear_dirty_log(d.slot, d.first_page, d.num_pages);
}
/*
* After we have updated the remote dirty bitmap, we update the
* cached bitmap as well for the memslot, then if another user
* clears the same region we know we shouldn't clear it again on
* the remote otherwise it's data loss as well.
*/
bitmap_clear(mem->dirty_bmap, bmap_start + start_delta,
size / psize);
/* This handles the NULL case well */
g_free(bmap_clear);
return ret;
}
/**
* kvm_physical_log_clear - Clear the kernel's dirty bitmap for range
*
* NOTE: this will be a no-op if we haven't enabled manual dirty log
* protection in the host kernel because in that case this operation
* will be done within log_sync().
*
* @kml: the kvm memory listener
* @section: the memory range to clear dirty bitmap
*/
static int kvm_physical_log_clear(KVMMemoryListener *kml,
MemoryRegionSection *section)
{
KVMState *s = kvm_state;
uint64_t start, size, offset, count;
KVMSlot *mem;
int ret = 0, i;
if (!s->manual_dirty_log_protect) {
/* No need to do explicit clear */
return ret;
}
start = section->offset_within_address_space;
size = int128_get64(section->size);
if (!size) {
/* Nothing more we can do... */
return ret;
}
kvm_slots_lock();
for (i = 0; i < s->nr_slots; i++) {
mem = &kml->slots[i];
/* Discard slots that are empty or do not overlap the section */
if (!mem->memory_size ||
mem->start_addr > start + size - 1 ||
start > mem->start_addr + mem->memory_size - 1) {
continue;
}
if (start >= mem->start_addr) {
/* The slot starts before section or is aligned to it. */
offset = start - mem->start_addr;
count = MIN(mem->memory_size - offset, size);
} else {
/* The slot starts after section. */
offset = 0;
count = MIN(mem->memory_size, size - (mem->start_addr - start));
}
ret = kvm_log_clear_one_slot(mem, kml->as_id, offset, count);
if (ret < 0) {
break;
}
}
kvm_slots_unlock();
return ret;
}
static void kvm_coalesce_mmio_region(MemoryListener *listener,
MemoryRegionSection *secion,
hwaddr start, hwaddr size)
{
KVMState *s = kvm_state;
if (s->coalesced_mmio) {
struct kvm_coalesced_mmio_zone zone;
zone.addr = start;
zone.size = size;
zone.pad = 0;
(void)kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
}
}
static void kvm_uncoalesce_mmio_region(MemoryListener *listener,
MemoryRegionSection *secion,
hwaddr start, hwaddr size)
{
KVMState *s = kvm_state;
if (s->coalesced_mmio) {
struct kvm_coalesced_mmio_zone zone;
zone.addr = start;
zone.size = size;
zone.pad = 0;
(void)kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
}
}
static void kvm_coalesce_pio_add(MemoryListener *listener,
MemoryRegionSection *section,
hwaddr start, hwaddr size)
{
KVMState *s = kvm_state;
if (s->coalesced_pio) {
struct kvm_coalesced_mmio_zone zone;
zone.addr = start;
zone.size = size;
zone.pio = 1;
(void)kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
}
}
static void kvm_coalesce_pio_del(MemoryListener *listener,
MemoryRegionSection *section,
hwaddr start, hwaddr size)
{
KVMState *s = kvm_state;
if (s->coalesced_pio) {
struct kvm_coalesced_mmio_zone zone;
zone.addr = start;
zone.size = size;
zone.pio = 1;
(void)kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
}
}
static MemoryListener kvm_coalesced_pio_listener = {
.name = "kvm-coalesced-pio",
.coalesced_io_add = kvm_coalesce_pio_add,
.coalesced_io_del = kvm_coalesce_pio_del,
};
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_vm_check_extension(KVMState *s, unsigned int extension)
{
int ret;
ret = kvm_vm_ioctl(s, KVM_CHECK_EXTENSION, extension);
if (ret < 0) {
/* VM wide version not implemented, use global one instead */
ret = kvm_check_extension(s, extension);
}
return ret;
}
typedef struct HWPoisonPage {
ram_addr_t ram_addr;
QLIST_ENTRY(HWPoisonPage) list;
} HWPoisonPage;
static QLIST_HEAD(, HWPoisonPage) hwpoison_page_list =
QLIST_HEAD_INITIALIZER(hwpoison_page_list);
static void kvm_unpoison_all(void *param)
{
HWPoisonPage *page, *next_page;
QLIST_FOREACH_SAFE(page, &hwpoison_page_list, list, next_page) {
QLIST_REMOVE(page, list);
qemu_ram_remap(page->ram_addr, TARGET_PAGE_SIZE);
g_free(page);
}
}
void kvm_hwpoison_page_add(ram_addr_t ram_addr)
{
HWPoisonPage *page;
QLIST_FOREACH(page, &hwpoison_page_list, list) {
if (page->ram_addr == ram_addr) {
return;
}
}
page = g_new(HWPoisonPage, 1);
page->ram_addr = ram_addr;
QLIST_INSERT_HEAD(&hwpoison_page_list, page, list);
}
static uint32_t adjust_ioeventfd_endianness(uint32_t val, uint32_t size)
{
#if HOST_BIG_ENDIAN != TARGET_BIG_ENDIAN
/* The kernel expects ioeventfd values in HOST_BIG_ENDIAN
* endianness, but the memory core hands them in target endianness.
* For example, PPC is always treated as big-endian even if running
* on KVM and on PPC64LE. Correct here.
*/
switch (size) {
case 2:
val = bswap16(val);
break;
case 4:
val = bswap32(val);
break;
}
#endif
return val;
}
static int kvm_set_ioeventfd_mmio(int fd, hwaddr addr, uint32_t val,
bool assign, uint32_t size, bool datamatch)
{
int ret;
struct kvm_ioeventfd iofd = {
.datamatch = datamatch ? adjust_ioeventfd_endianness(val, size) : 0,
.addr = addr,
.len = size,
.flags = 0,
.fd = fd,
};
trace_kvm_set_ioeventfd_mmio(fd, (uint64_t)addr, val, assign, size,
datamatch);
if (!kvm_enabled()) {
return -ENOSYS;
}
if (datamatch) {
iofd.flags |= KVM_IOEVENTFD_FLAG_DATAMATCH;
}
if (!assign) {
iofd.flags |= KVM_IOEVENTFD_FLAG_DEASSIGN;
}
ret = kvm_vm_ioctl(kvm_state, KVM_IOEVENTFD, &iofd);
if (ret < 0) {
return -errno;
}
return 0;
}
static int kvm_set_ioeventfd_pio(int fd, uint16_t addr, uint16_t val,
bool assign, uint32_t size, bool datamatch)
{
struct kvm_ioeventfd kick = {
.datamatch = datamatch ? adjust_ioeventfd_endianness(val, size) : 0,
.addr = addr,
.flags = KVM_IOEVENTFD_FLAG_PIO,
.len = size,
.fd = fd,
};
int r;
trace_kvm_set_ioeventfd_pio(fd, addr, val, assign, size, datamatch);
if (!kvm_enabled()) {
return -ENOSYS;
}
if (datamatch) {
kick.flags |= KVM_IOEVENTFD_FLAG_DATAMATCH;
}
if (!assign) {
kick.flags |= KVM_IOEVENTFD_FLAG_DEASSIGN;
}
r = kvm_vm_ioctl(kvm_state, KVM_IOEVENTFD, &kick);
if (r < 0) {
return r;
}
return 0;
}
static int kvm_check_many_ioeventfds(void)
{
/* Userspace can use ioeventfd for io notification. This requires a host
* that supports eventfd(2) and an I/O thread; since eventfd does not
* support SIGIO it cannot interrupt the vcpu.
*
* Older kernels have a 6 device limit on the KVM io bus. Find out so we
* can avoid creating too many ioeventfds.
*/
#if defined(CONFIG_EVENTFD)
int ioeventfds[7];
int i, ret = 0;
for (i = 0; i < ARRAY_SIZE(ioeventfds); i++) {
ioeventfds[i] = eventfd(0, EFD_CLOEXEC);
if (ioeventfds[i] < 0) {
break;
}
ret = kvm_set_ioeventfd_pio(ioeventfds[i], 0, i, true, 2, true);
if (ret < 0) {
close(ioeventfds[i]);
break;
}
}
/* Decide whether many devices are supported or not */
ret = i == ARRAY_SIZE(ioeventfds);
while (i-- > 0) {
kvm_set_ioeventfd_pio(ioeventfds[i], 0, i, false, 2, true);
close(ioeventfds[i]);
}
return ret;
#else
return 0;
#endif
}
static const KVMCapabilityInfo *
kvm_check_extension_list(KVMState *s, const KVMCapabilityInfo *list)
{
while (list->name) {
if (!kvm_check_extension(s, list->value)) {
return list;
}
list++;
}
return NULL;
}
void kvm_set_max_memslot_size(hwaddr max_slot_size)
{
g_assert(
ROUND_UP(max_slot_size, qemu_real_host_page_size()) == max_slot_size
);
kvm_max_slot_size = max_slot_size;
}
static void kvm_set_phys_mem(KVMMemoryListener *kml,
MemoryRegionSection *section, bool add)
{
KVMSlot *mem;
int err;
MemoryRegion *mr = section->mr;
bool writable = !mr->readonly && !mr->rom_device;
hwaddr start_addr, size, slot_size, mr_offset;
ram_addr_t ram_start_offset;
void *ram;
if (!memory_region_is_ram(mr)) {
if (writable || !kvm_readonly_mem_allowed) {
return;
} else if (!mr->romd_mode) {
/* If the memory device is not in romd_mode, then we actually want
* to remove the kvm memory slot so all accesses will trap. */
add = false;
}
}
size = kvm_align_section(section, &start_addr);
if (!size) {
return;
}
/* The offset of the kvmslot within the memory region */
mr_offset = section->offset_within_region + start_addr -
section->offset_within_address_space;
/* use aligned delta to align the ram address and offset */
ram = memory_region_get_ram_ptr(mr) + mr_offset;
ram_start_offset = memory_region_get_ram_addr(mr) + mr_offset;
kvm_slots_lock();
if (!add) {
do {
slot_size = MIN(kvm_max_slot_size, size);
mem = kvm_lookup_matching_slot(kml, start_addr, slot_size);
if (!mem) {
goto out;
}
if (mem->flags & KVM_MEM_LOG_DIRTY_PAGES) {
/*
* NOTE: We should be aware of the fact that here we're only
* doing a best effort to sync dirty bits. No matter whether
* we're using dirty log or dirty ring, we ignored two facts:
*
* (1) dirty bits can reside in hardware buffers (PML)
*
* (2) after we collected dirty bits here, pages can be dirtied
* again before we do the final KVM_SET_USER_MEMORY_REGION to
* remove the slot.
*
* Not easy. Let's cross the fingers until it's fixed.
*/
if (kvm_state->kvm_dirty_ring_size) {
kvm_dirty_ring_reap_locked(kvm_state, NULL);
} else {
kvm_slot_get_dirty_log(kvm_state, mem);
}
kvm_slot_sync_dirty_pages(mem);
}
/* unregister the slot */
g_free(mem->dirty_bmap);
mem->dirty_bmap = NULL;
mem->memory_size = 0;
mem->flags = 0;
err = kvm_set_user_memory_region(kml, mem, false);
if (err) {
fprintf(stderr, "%s: error unregistering slot: %s\n",
__func__, strerror(-err));
abort();
}
start_addr += slot_size;
size -= slot_size;
} while (size);
goto out;
}
/* register the new slot */
do {
slot_size = MIN(kvm_max_slot_size, size);
mem = kvm_alloc_slot(kml);
mem->as_id = kml->as_id;
mem->memory_size = slot_size;
mem->start_addr = start_addr;
mem->ram_start_offset = ram_start_offset;
mem->ram = ram;
mem->flags = kvm_mem_flags(mr);
kvm_slot_init_dirty_bitmap(mem);
err = kvm_set_user_memory_region(kml, mem, true);
if (err) {
fprintf(stderr, "%s: error registering slot: %s\n", __func__,
strerror(-err));
abort();
}
start_addr += slot_size;
ram_start_offset += slot_size;
ram += slot_size;
size -= slot_size;
} while (size);
out:
kvm_slots_unlock();
}
static void *kvm_dirty_ring_reaper_thread(void *data)
{
KVMState *s = data;
struct KVMDirtyRingReaper *r = &s->reaper;
rcu_register_thread();
trace_kvm_dirty_ring_reaper("init");
while (true) {
r->reaper_state = KVM_DIRTY_RING_REAPER_WAIT;
trace_kvm_dirty_ring_reaper("wait");
/*
* TODO: provide a smarter timeout rather than a constant?
*/
sleep(1);
/* keep sleeping so that dirtylimit not be interfered by reaper */
if (dirtylimit_in_service()) {
continue;
}
trace_kvm_dirty_ring_reaper("wakeup");
r->reaper_state = KVM_DIRTY_RING_REAPER_REAPING;
qemu_mutex_lock_iothread();
kvm_dirty_ring_reap(s, NULL);
qemu_mutex_unlock_iothread();
r->reaper_iteration++;
}
trace_kvm_dirty_ring_reaper("exit");
rcu_unregister_thread();
return NULL;
}
static int kvm_dirty_ring_reaper_init(KVMState *s)
{
struct KVMDirtyRingReaper *r = &s->reaper;
qemu_thread_create(&r->reaper_thr, "kvm-reaper",
kvm_dirty_ring_reaper_thread,
s, QEMU_THREAD_JOINABLE);
return 0;
}
static void kvm_region_add(MemoryListener *listener,
MemoryRegionSection *section)
{
KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
memory_region_ref(section->mr);
kvm_set_phys_mem(kml, section, true);
}
static void kvm_region_del(MemoryListener *listener,
MemoryRegionSection *section)
{
KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
kvm_set_phys_mem(kml, section, false);
memory_region_unref(section->mr);
}
static void kvm_log_sync(MemoryListener *listener,
MemoryRegionSection *section)
{
KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
kvm_slots_lock();
kvm_physical_sync_dirty_bitmap(kml, section);
kvm_slots_unlock();
}
static void kvm_log_sync_global(MemoryListener *l)
{
KVMMemoryListener *kml = container_of(l, KVMMemoryListener, listener);
KVMState *s = kvm_state;
KVMSlot *mem;
int i;
/* Flush all kernel dirty addresses into KVMSlot dirty bitmap */
kvm_dirty_ring_flush();
/*
* TODO: make this faster when nr_slots is big while there are
* only a few used slots (small VMs).
*/
kvm_slots_lock();
for (i = 0; i < s->nr_slots; i++) {
mem = &kml->slots[i];
if (mem->memory_size && mem->flags & KVM_MEM_LOG_DIRTY_PAGES) {
kvm_slot_sync_dirty_pages(mem);
/*
* This is not needed by KVM_GET_DIRTY_LOG because the
* ioctl will unconditionally overwrite the whole region.
* However kvm dirty ring has no such side effect.
*/
kvm_slot_reset_dirty_pages(mem);
}
}
kvm_slots_unlock();
}
static void kvm_log_clear(MemoryListener *listener,
MemoryRegionSection *section)
{
KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
int r;
r = kvm_physical_log_clear(kml, section);
if (r < 0) {
error_report_once("%s: kvm log clear failed: mr=%s "
"offset=%"HWADDR_PRIx" size=%"PRIx64, __func__,
section->mr->name, section->offset_within_region,
int128_get64(section->size));
abort();
}
}
static void kvm_mem_ioeventfd_add(MemoryListener *listener,
MemoryRegionSection *section,
bool match_data, uint64_t data,
EventNotifier *e)
{
int fd = event_notifier_get_fd(e);
int r;
r = kvm_set_ioeventfd_mmio(fd, section->offset_within_address_space,
data, true, int128_get64(section->size),
match_data);
if (r < 0) {
fprintf(stderr, "%s: error adding ioeventfd: %s (%d)\n",
__func__, strerror(-r), -r);
abort();
}
}
static void kvm_mem_ioeventfd_del(MemoryListener *listener,
MemoryRegionSection *section,
bool match_data, uint64_t data,
EventNotifier *e)
{
int fd = event_notifier_get_fd(e);
int r;
r = kvm_set_ioeventfd_mmio(fd, section->offset_within_address_space,
data, false, int128_get64(section->size),
match_data);
if (r < 0) {
fprintf(stderr, "%s: error deleting ioeventfd: %s (%d)\n",
__func__, strerror(-r), -r);
abort();
}
}
static void kvm_io_ioeventfd_add(MemoryListener *listener,
MemoryRegionSection *section,
bool match_data, uint64_t data,
EventNotifier *e)
{
int fd = event_notifier_get_fd(e);
int r;
r = kvm_set_ioeventfd_pio(fd, section->offset_within_address_space,
data, true, int128_get64(section->size),
match_data);
if (r < 0) {
fprintf(stderr, "%s: error adding ioeventfd: %s (%d)\n",
__func__, strerror(-r), -r);
abort();
}
}
static void kvm_io_ioeventfd_del(MemoryListener *listener,
MemoryRegionSection *section,
bool match_data, uint64_t data,
EventNotifier *e)
{
int fd = event_notifier_get_fd(e);
int r;
r = kvm_set_ioeventfd_pio(fd, section->offset_within_address_space,
data, false, int128_get64(section->size),
match_data);
if (r < 0) {
fprintf(stderr, "%s: error deleting ioeventfd: %s (%d)\n",
__func__, strerror(-r), -r);
abort();
}
}
void kvm_memory_listener_register(KVMState *s, KVMMemoryListener *kml,
AddressSpace *as, int as_id, const char *name)
{
int i;
kml->slots = g_new0(KVMSlot, s->nr_slots);
kml->as_id = as_id;
for (i = 0; i < s->nr_slots; i++) {
kml->slots[i].slot = i;
}
kml->listener.region_add = kvm_region_add;
kml->listener.region_del = kvm_region_del;
kml->listener.log_start = kvm_log_start;
kml->listener.log_stop = kvm_log_stop;
kml->listener.priority = 10;
kml->listener.name = name;
if (s->kvm_dirty_ring_size) {
kml->listener.log_sync_global = kvm_log_sync_global;
} else {
kml->listener.log_sync = kvm_log_sync;
kml->listener.log_clear = kvm_log_clear;
}
memory_listener_register(&kml->listener, as);
for (i = 0; i < s->nr_as; ++i) {
if (!s->as[i].as) {
s->as[i].as = as;
s->as[i].ml = kml;
break;
}
}
}
static MemoryListener kvm_io_listener = {
.name = "kvm-io",
.eventfd_add = kvm_io_ioeventfd_add,
.eventfd_del = kvm_io_ioeventfd_del,
.priority = 10,
};
int kvm_set_irq(KVMState *s, int irq, int level)
{
struct kvm_irq_level event;
int ret;
assert(kvm_async_interrupts_enabled());
event.level = level;
event.irq = irq;
ret = kvm_vm_ioctl(s, s->irq_set_ioctl, &event);
if (ret < 0) {
perror("kvm_set_irq");
abort();
}
return (s->irq_set_ioctl == KVM_IRQ_LINE) ? 1 : event.status;
}
#ifdef KVM_CAP_IRQ_ROUTING
typedef struct KVMMSIRoute {
struct kvm_irq_routing_entry kroute;
QTAILQ_ENTRY(KVMMSIRoute) entry;
} KVMMSIRoute;
static void set_gsi(KVMState *s, unsigned int gsi)
{
set_bit(gsi, s->used_gsi_bitmap);
}
static void clear_gsi(KVMState *s, unsigned int gsi)
{
clear_bit(gsi, s->used_gsi_bitmap);
}
void kvm_init_irq_routing(KVMState *s)
{
int gsi_count, i;
gsi_count = kvm_check_extension(s, KVM_CAP_IRQ_ROUTING) - 1;
if (gsi_count > 0) {
/* Round up so we can search ints using ffs */
s->used_gsi_bitmap = bitmap_new(gsi_count);
s->gsi_count = gsi_count;
}
s->irq_routes = g_malloc0(sizeof(*s->irq_routes));
s->nr_allocated_irq_routes = 0;
if (!kvm_direct_msi_allowed) {
for (i = 0; i < KVM_MSI_HASHTAB_SIZE; i++) {
QTAILQ_INIT(&s->msi_hashtab[i]);
}
}
kvm_arch_init_irq_routing(s);
}
void kvm_irqchip_commit_routes(KVMState *s)
{
int ret;
if (kvm_gsi_direct_mapping()) {
return;
}
if (!kvm_gsi_routing_enabled()) {
return;
}
s->irq_routes->flags = 0;
trace_kvm_irqchip_commit_routes();
ret = kvm_vm_ioctl(s, KVM_SET_GSI_ROUTING, s->irq_routes);
assert(ret == 0);
}
static void kvm_add_routing_entry(KVMState *s,
struct kvm_irq_routing_entry *entry)
{
struct kvm_irq_routing_entry *new;
int n, size;
if (s->irq_routes->nr == s->nr_allocated_irq_routes) {
n = s->nr_allocated_irq_routes * 2;
if (n < 64) {
n = 64;
}
size = sizeof(struct kvm_irq_routing);
size += n * sizeof(*new);
s->irq_routes = g_realloc(s->irq_routes, size);
s->nr_allocated_irq_routes = n;
}
n = s->irq_routes->nr++;
new = &s->irq_routes->entries[n];
*new = *entry;
set_gsi(s, entry->gsi);
}
static int kvm_update_routing_entry(KVMState *s,
struct kvm_irq_routing_entry *new_entry)
{
struct kvm_irq_routing_entry *entry;
int n;
for (n = 0; n < s->irq_routes->nr; n++) {
entry = &s->irq_routes->entries[n];
if (entry->gsi != new_entry->gsi) {
continue;
}
if(!memcmp(entry, new_entry, sizeof *entry)) {
return 0;
}
*entry = *new_entry;
return 0;
}
return -ESRCH;
}
void kvm_irqchip_add_irq_route(KVMState *s, int irq, int irqchip, int pin)
{
struct kvm_irq_routing_entry e = {};
assert(pin < s->gsi_count);
e.gsi = irq;
e.type = KVM_IRQ_ROUTING_IRQCHIP;
e.flags = 0;
e.u.irqchip.irqchip = irqchip;
e.u.irqchip.pin = pin;
kvm_add_routing_entry(s, &e);
}
void kvm_irqchip_release_virq(KVMState *s, int virq)
{
struct kvm_irq_routing_entry *e;
int i;
if (kvm_gsi_direct_mapping()) {
return;
}
for (i = 0; i < s->irq_routes->nr; i++) {
e = &s->irq_routes->entries[i];
if (e->gsi == virq) {
s->irq_routes->nr--;
*e = s->irq_routes->entries[s->irq_routes->nr];
}
}
clear_gsi(s, virq);
kvm_arch_release_virq_post(virq);
trace_kvm_irqchip_release_virq(virq);
}
void kvm_irqchip_add_change_notifier(Notifier *n)
{
notifier_list_add(&kvm_irqchip_change_notifiers, n);
}
void kvm_irqchip_remove_change_notifier(Notifier *n)
{
notifier_remove(n);
}
void kvm_irqchip_change_notify(void)
{
notifier_list_notify(&kvm_irqchip_change_notifiers, NULL);
}
static unsigned int kvm_hash_msi(uint32_t data)
{
/* This is optimized for IA32 MSI layout. However, no other arch shall
* repeat the mistake of not providing a direct MSI injection API. */
return data & 0xff;
}
static void kvm_flush_dynamic_msi_routes(KVMState *s)
{
KVMMSIRoute *route, *next;
unsigned int hash;
for (hash = 0; hash < KVM_MSI_HASHTAB_SIZE; hash++) {
QTAILQ_FOREACH_SAFE(route, &s->msi_hashtab[hash], entry, next) {
kvm_irqchip_release_virq(s, route->kroute.gsi);
QTAILQ_REMOVE(&s->msi_hashtab[hash], route, entry);
g_free(route);
}
}
}
static int kvm_irqchip_get_virq(KVMState *s)
{
int next_virq;
/*
* PIC and IOAPIC share the first 16 GSI numbers, thus the available
* GSI numbers are more than the number of IRQ route. Allocating a GSI
* number can succeed even though a new route entry cannot be added.
* When this happens, flush dynamic MSI entries to free IRQ route entries.
*/
if (!kvm_direct_msi_allowed && s->irq_routes->nr == s->gsi_count) {
kvm_flush_dynamic_msi_routes(s);
}
/* Return the lowest unused GSI in the bitmap */
next_virq = find_first_zero_bit(s->used_gsi_bitmap, s->gsi_count);
if (next_virq >= s->gsi_count) {
return -ENOSPC;
} else {
return next_virq;
}
}
static KVMMSIRoute *kvm_lookup_msi_route(KVMState *s, MSIMessage msg)
{
unsigned int hash = kvm_hash_msi(msg.data);
KVMMSIRoute *route;
QTAILQ_FOREACH(route, &s->msi_hashtab[hash], entry) {
if (route->kroute.u.msi.address_lo == (uint32_t)msg.address &&
route->kroute.u.msi.address_hi == (msg.address >> 32) &&
route->kroute.u.msi.data == le32_to_cpu(msg.data)) {
return route;
}
}
return NULL;
}
int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg)
{
struct kvm_msi msi;
KVMMSIRoute *route;
if (kvm_direct_msi_allowed) {
msi.address_lo = (uint32_t)msg.address;
msi.address_hi = msg.address >> 32;
msi.data = le32_to_cpu(msg.data);
msi.flags = 0;
memset(msi.pad, 0, sizeof(msi.pad));
return kvm_vm_ioctl(s, KVM_SIGNAL_MSI, &msi);
}
route = kvm_lookup_msi_route(s, msg);
if (!route) {
int virq;
virq = kvm_irqchip_get_virq(s);
if (virq < 0) {
return virq;
}
route = g_new0(KVMMSIRoute, 1);
route->kroute.gsi = virq;
route->kroute.type = KVM_IRQ_ROUTING_MSI;
route->kroute.flags = 0;
route->kroute.u.msi.address_lo = (uint32_t)msg.address;
route->kroute.u.msi.address_hi = msg.address >> 32;
route->kroute.u.msi.data = le32_to_cpu(msg.data);
kvm_add_routing_entry(s, &route->kroute);
kvm_irqchip_commit_routes(s);
QTAILQ_INSERT_TAIL(&s->msi_hashtab[kvm_hash_msi(msg.data)], route,
entry);
}
assert(route->kroute.type == KVM_IRQ_ROUTING_MSI);
return kvm_set_irq(s, route->kroute.gsi, 1);
}
int kvm_irqchip_add_msi_route(KVMRouteChange *c, int vector, PCIDevice *dev)
{
struct kvm_irq_routing_entry kroute = {};
int virq;
KVMState *s = c->s;
MSIMessage msg = {0, 0};
if (pci_available && dev) {
msg = pci_get_msi_message(dev, vector);
}
if (kvm_gsi_direct_mapping()) {
return kvm_arch_msi_data_to_gsi(msg.data);
}
if (!kvm_gsi_routing_enabled()) {
return -ENOSYS;
}
virq = kvm_irqchip_get_virq(s);
if (virq < 0) {
return virq;
}
kroute.gsi = virq;
kroute.type = KVM_IRQ_ROUTING_MSI;
kroute.flags = 0;
kroute.u.msi.address_lo = (uint32_t)msg.address;
kroute.u.msi.address_hi = msg.address >> 32;
kroute.u.msi.data = le32_to_cpu(msg.data);
if (pci_available && kvm_msi_devid_required()) {
kroute.flags = KVM_MSI_VALID_DEVID;
kroute.u.msi.devid = pci_requester_id(dev);
}
if (kvm_arch_fixup_msi_route(&kroute, msg.address, msg.data, dev)) {
kvm_irqchip_release_virq(s, virq);
return -EINVAL;
}
trace_kvm_irqchip_add_msi_route(dev ? dev->name : (char *)"N/A",
vector, virq);
kvm_add_routing_entry(s, &kroute);
kvm_arch_add_msi_route_post(&kroute, vector, dev);
c->changes++;
return virq;
}
int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg,
PCIDevice *dev)
{
struct kvm_irq_routing_entry kroute = {};
if (kvm_gsi_direct_mapping()) {
return 0;
}
if (!kvm_irqchip_in_kernel()) {
return -ENOSYS;
}
kroute.gsi = virq;
kroute.type = KVM_IRQ_ROUTING_MSI;
kroute.flags = 0;
kroute.u.msi.address_lo = (uint32_t)msg.address;
kroute.u.msi.address_hi = msg.address >> 32;
kroute.u.msi.data = le32_to_cpu(msg.data);
if (pci_available && kvm_msi_devid_required()) {
kroute.flags = KVM_MSI_VALID_DEVID;
kroute.u.msi.devid = pci_requester_id(dev);
}
if (kvm_arch_fixup_msi_route(&kroute, msg.address, msg.data, dev)) {
return -EINVAL;
}
trace_kvm_irqchip_update_msi_route(virq);
return kvm_update_routing_entry(s, &kroute);
}
static int kvm_irqchip_assign_irqfd(KVMState *s, EventNotifier *event,
EventNotifier *resample, int virq,
bool assign)
{
int fd = event_notifier_get_fd(event);
int rfd = resample ? event_notifier_get_fd(resample) : -1;
struct kvm_irqfd irqfd = {
.fd = fd,
.gsi = virq,
.flags = assign ? 0 : KVM_IRQFD_FLAG_DEASSIGN,
};
if (rfd != -1) {
assert(assign);
if (kvm_irqchip_is_split()) {
/*
* When the slow irqchip (e.g. IOAPIC) is in the
* userspace, KVM kernel resamplefd will not work because
* the EOI of the interrupt will be delivered to userspace
* instead, so the KVM kernel resamplefd kick will be
* skipped. The userspace here mimics what the kernel
* provides with resamplefd, remember the resamplefd and
* kick it when we receive EOI of this IRQ.
*
* This is hackery because IOAPIC is mostly bypassed
* (except EOI broadcasts) when irqfd is used. However
* this can bring much performance back for split irqchip
* with INTx IRQs (for VFIO, this gives 93% perf of the
* full fast path, which is 46% perf boost comparing to
* the INTx slow path).
*/
kvm_resample_fd_insert(virq, resample);
} else {
irqfd.flags |= KVM_IRQFD_FLAG_RESAMPLE;
irqfd.resamplefd = rfd;
}
} else if (!assign) {
if (kvm_irqchip_is_split()) {
kvm_resample_fd_remove(virq);
}
}
if (!kvm_irqfds_enabled()) {
return -ENOSYS;
}
return kvm_vm_ioctl(s, KVM_IRQFD, &irqfd);
}
int kvm_irqchip_add_adapter_route(KVMState *s, AdapterInfo *adapter)
{
struct kvm_irq_routing_entry kroute = {};
int virq;
if (!kvm_gsi_routing_enabled()) {
return -ENOSYS;
}
virq = kvm_irqchip_get_virq(s);
if (virq < 0) {
return virq;
}
kroute.gsi = virq;
kroute.type = KVM_IRQ_ROUTING_S390_ADAPTER;
kroute.flags = 0;
kroute.u.adapter.summary_addr = adapter->summary_addr;
kroute.u.adapter.ind_addr = adapter->ind_addr;
kroute.u.adapter.summary_offset = adapter->summary_offset;
kroute.u.adapter.ind_offset = adapter->ind_offset;
kroute.u.adapter.adapter_id = adapter->adapter_id;
kvm_add_routing_entry(s, &kroute);
return virq;
}
int kvm_irqchip_add_hv_sint_route(KVMState *s, uint32_t vcpu, uint32_t sint)
{
struct kvm_irq_routing_entry kroute = {};
int virq;
if (!kvm_gsi_routing_enabled()) {
return -ENOSYS;
}
if (!kvm_check_extension(s, KVM_CAP_HYPERV_SYNIC)) {
return -ENOSYS;
}
virq = kvm_irqchip_get_virq(s);
if (virq < 0) {
return virq;
}
kroute.gsi = virq;
kroute.type = KVM_IRQ_ROUTING_HV_SINT;
kroute.flags = 0;
kroute.u.hv_sint.vcpu = vcpu;
kroute.u.hv_sint.sint = sint;
kvm_add_routing_entry(s, &kroute);
kvm_irqchip_commit_routes(s);
return virq;
}
#else /* !KVM_CAP_IRQ_ROUTING */
void kvm_init_irq_routing(KVMState *s)
{
}
void kvm_irqchip_release_virq(KVMState *s, int virq)
{
}
int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg)
{
abort();
}
int kvm_irqchip_add_msi_route(KVMRouteChange *c, int vector, PCIDevice *dev)
{
return -ENOSYS;
}
int kvm_irqchip_add_adapter_route(KVMState *s, AdapterInfo *adapter)
{
return -ENOSYS;
}
int kvm_irqchip_add_hv_sint_route(KVMState *s, uint32_t vcpu, uint32_t sint)
{
return -ENOSYS;
}
static int kvm_irqchip_assign_irqfd(KVMState *s, EventNotifier *event,
EventNotifier *resample, int virq,
bool assign)
{
abort();
}
int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg)
{
return -ENOSYS;
}
#endif /* !KVM_CAP_IRQ_ROUTING */
int kvm_irqchip_add_irqfd_notifier_gsi(KVMState *s, EventNotifier *n,
EventNotifier *rn, int virq)
{
return kvm_irqchip_assign_irqfd(s, n, rn, virq, true);
}
int kvm_irqchip_remove_irqfd_notifier_gsi(KVMState *s, EventNotifier *n,
int virq)
{
return kvm_irqchip_assign_irqfd(s, n, NULL, virq, false);
}
int kvm_irqchip_add_irqfd_notifier(KVMState *s, EventNotifier *n,
EventNotifier *rn, qemu_irq irq)
{
gpointer key, gsi;
gboolean found = g_hash_table_lookup_extended(s->gsimap, irq, &key, &gsi);
if (!found) {
return -ENXIO;
}
return kvm_irqchip_add_irqfd_notifier_gsi(s, n, rn, GPOINTER_TO_INT(gsi));
}
int kvm_irqchip_remove_irqfd_notifier(KVMState *s, EventNotifier *n,
qemu_irq irq)
{
gpointer key, gsi;
gboolean found = g_hash_table_lookup_extended(s->gsimap, irq, &key, &gsi);
if (!found) {
return -ENXIO;
}
return kvm_irqchip_remove_irqfd_notifier_gsi(s, n, GPOINTER_TO_INT(gsi));
}
void kvm_irqchip_set_qemuirq_gsi(KVMState *s, qemu_irq irq, int gsi)
{
g_hash_table_insert(s->gsimap, irq, GINT_TO_POINTER(gsi));
}
static void kvm_irqchip_create(KVMState *s)
{
int ret;
assert(s->kernel_irqchip_split != ON_OFF_AUTO_AUTO);
if (kvm_check_extension(s, KVM_CAP_IRQCHIP)) {
;
} else if (kvm_check_extension(s, KVM_CAP_S390_IRQCHIP)) {
ret = kvm_vm_enable_cap(s, KVM_CAP_S390_IRQCHIP, 0);
if (ret < 0) {
fprintf(stderr, "Enable kernel irqchip failed: %s\n", strerror(-ret));
exit(1);
}
} else {
return;
}
/* First probe and see if there's a arch-specific hook to create the
* in-kernel irqchip for us */
ret = kvm_arch_irqchip_create(s);
if (ret == 0) {
if (s->kernel_irqchip_split == ON_OFF_AUTO_ON) {
error_report("Split IRQ chip mode not supported.");
exit(1);
} else {
ret = kvm_vm_ioctl(s, KVM_CREATE_IRQCHIP);
}
}
if (ret < 0) {
fprintf(stderr, "Create kernel irqchip failed: %s\n", strerror(-ret));
exit(1);
}
kvm_kernel_irqchip = true;
/* If we have an in-kernel IRQ chip then we must have asynchronous
* interrupt delivery (though the reverse is not necessarily true)
*/
kvm_async_interrupts_allowed = true;
kvm_halt_in_kernel_allowed = true;
kvm_init_irq_routing(s);
s->gsimap = g_hash_table_new(g_direct_hash, g_direct_equal);
}
/* Find number of supported CPUs using the recommended
* procedure from the kernel API documentation to cope with
* older kernels that may be missing capabilities.
*/
static int kvm_recommended_vcpus(KVMState *s)
{
int ret = kvm_vm_check_extension(s, KVM_CAP_NR_VCPUS);
return (ret) ? ret : 4;
}
static int kvm_max_vcpus(KVMState *s)
{
int ret = kvm_check_extension(s, KVM_CAP_MAX_VCPUS);
return (ret) ? ret : kvm_recommended_vcpus(s);
}
static int kvm_max_vcpu_id(KVMState *s)
{
int ret = kvm_check_extension(s, KVM_CAP_MAX_VCPU_ID);
return (ret) ? ret : kvm_max_vcpus(s);
}
bool kvm_vcpu_id_is_valid(int vcpu_id)
{
KVMState *s = KVM_STATE(current_accel());
return vcpu_id >= 0 && vcpu_id < kvm_max_vcpu_id(s);
}
bool kvm_dirty_ring_enabled(void)
{
return kvm_state->kvm_dirty_ring_size ? true : false;
}
static void query_stats_cb(StatsResultList **result, StatsTarget target,
strList *names, strList *targets, Error **errp);
static void query_stats_schemas_cb(StatsSchemaList **result, Error **errp);
uint32_t kvm_dirty_ring_size(void)
{
return kvm_state->kvm_dirty_ring_size;
}
static int kvm_init(MachineState *ms)
{
MachineClass *mc = MACHINE_GET_CLASS(ms);
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";
struct {
const char *name;
int num;
} num_cpus[] = {
{ "SMP", ms->smp.cpus },
{ "hotpluggable", ms->smp.max_cpus },
{ NULL, }
}, *nc = num_cpus;
int soft_vcpus_limit, hard_vcpus_limit;
KVMState *s;
const KVMCapabilityInfo *missing_cap;
int ret;
int type = 0;
uint64_t dirty_log_manual_caps;
qemu_mutex_init(&kml_slots_lock);
s = KVM_STATE(ms->accelerator);
/*
* On systems where the kernel can support different base page
* sizes, host page size may be different from TARGET_PAGE_SIZE,
* even with KVM. TARGET_PAGE_SIZE is assumed to be the minimum
* page size for the system though.
*/
assert(TARGET_PAGE_SIZE <= qemu_real_host_page_size());
s->sigmask_len = 8;
#ifdef KVM_CAP_SET_GUEST_DEBUG
QTAILQ_INIT(&s->kvm_sw_breakpoints);
#endif
QLIST_INIT(&s->kvm_parked_vcpus);
s->fd = qemu_open_old("/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;
}
kvm_immediate_exit = kvm_check_extension(s, KVM_CAP_IMMEDIATE_EXIT);
s->nr_slots = kvm_check_extension(s, KVM_CAP_NR_MEMSLOTS);
/* If unspecified, use the default value */
if (!s->nr_slots) {
s->nr_slots = 32;
}
s->nr_as = kvm_check_extension(s, KVM_CAP_MULTI_ADDRESS_SPACE);
if (s->nr_as <= 1) {
s->nr_as = 1;
}
s->as = g_new0(struct KVMAs, s->nr_as);
if (object_property_find(OBJECT(current_machine), "kvm-type")) {
g_autofree char *kvm_type = object_property_get_str(OBJECT(current_machine),
"kvm-type",
&error_abort);
type = mc->kvm_type(ms, kvm_type);
} else if (mc->kvm_type) {
type = mc->kvm_type(ms, NULL);
}
do {
ret = kvm_ioctl(s, KVM_CREATE_VM, type);
} while (ret == -EINTR);
if (ret < 0) {
fprintf(stderr, "ioctl(KVM_CREATE_VM) failed: %d %s\n", -ret,
strerror(-ret));
#ifdef TARGET_S390X
if (ret == -EINVAL) {
fprintf(stderr,
"Host kernel setup problem detected. Please verify:\n");
fprintf(stderr, "- for kernels supporting the switch_amode or"
" user_mode parameters, whether\n");
fprintf(stderr,
" user space is running in primary address space\n");
fprintf(stderr,
"- for kernels supporting the vm.allocate_pgste sysctl, "
"whether it is enabled\n");
}
#elif defined(TARGET_PPC)
if (ret == -EINVAL) {
fprintf(stderr,
"PPC KVM module is not loaded. Try modprobe kvm_%s.\n",
(type == 2) ? "pr" : "hv");
}
#endif
goto err;
}
s->vmfd = ret;
/* check the vcpu limits */
soft_vcpus_limit = kvm_recommended_vcpus(s);
hard_vcpus_limit = kvm_max_vcpus(s);
while (nc->name) {
if (nc->num > soft_vcpus_limit) {
warn_report("Number of %s cpus requested (%d) exceeds "
"the recommended cpus supported by KVM (%d)",
nc->name, nc->num, soft_vcpus_limit);
if (nc->num > hard_vcpus_limit) {
fprintf(stderr, "Number of %s cpus requested (%d) exceeds "
"the maximum cpus supported by KVM (%d)\n",
nc->name, nc->num, hard_vcpus_limit);
exit(1);
}
}
nc++;
}
missing_cap = kvm_check_extension_list(s, kvm_required_capabilites);
if (!missing_cap) {
missing_cap =
kvm_check_extension_list(s, kvm_arch_required_capabilities);
}
if (missing_cap) {
ret = -EINVAL;
fprintf(stderr, "kvm does not support %s\n%s",
missing_cap->name, upgrade_note);
goto err;
}
s->coalesced_mmio = kvm_check_extension(s, KVM_CAP_COALESCED_MMIO);
s->coalesced_pio = s->coalesced_mmio &&
kvm_check_extension(s, KVM_CAP_COALESCED_PIO);
/*
* Enable KVM dirty ring if supported, otherwise fall back to
* dirty logging mode
*/
if (s->kvm_dirty_ring_size > 0) {
uint64_t ring_bytes;
ring_bytes = s->kvm_dirty_ring_size * sizeof(struct kvm_dirty_gfn);
/* Read the max supported pages */
ret = kvm_vm_check_extension(s, KVM_CAP_DIRTY_LOG_RING);
if (ret > 0) {
if (ring_bytes > ret) {
error_report("KVM dirty ring size %" PRIu32 " too big "
"(maximum is %ld). Please use a smaller value.",
s->kvm_dirty_ring_size,
(long)ret / sizeof(struct kvm_dirty_gfn));
ret = -EINVAL;
goto err;
}
ret = kvm_vm_enable_cap(s, KVM_CAP_DIRTY_LOG_RING, 0, ring_bytes);
if (ret) {
error_report("Enabling of KVM dirty ring failed: %s. "
"Suggested minimum value is 1024.", strerror(-ret));
goto err;
}
s->kvm_dirty_ring_bytes = ring_bytes;
} else {
warn_report("KVM dirty ring not available, using bitmap method");
s->kvm_dirty_ring_size = 0;
}
}
/*
* KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is not needed when dirty ring is
* enabled. More importantly, KVM_DIRTY_LOG_INITIALLY_SET will assume no
* page is wr-protected initially, which is against how kvm dirty ring is
* usage - kvm dirty ring requires all pages are wr-protected at the very
* beginning. Enabling this feature for dirty ring causes data corruption.
*
* TODO: Without KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 and kvm clear dirty log,
* we may expect a higher stall time when starting the migration. In the
* future we can enable KVM_CLEAR_DIRTY_LOG to work with dirty ring too:
* instead of clearing dirty bit, it can be a way to explicitly wr-protect
* guest pages.
*/
if (!s->kvm_dirty_ring_size) {
dirty_log_manual_caps =
kvm_check_extension(s, KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2);
dirty_log_manual_caps &= (KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE |
KVM_DIRTY_LOG_INITIALLY_SET);
s->manual_dirty_log_protect = dirty_log_manual_caps;
if (dirty_log_manual_caps) {
ret = kvm_vm_enable_cap(s, KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2, 0,
dirty_log_manual_caps);
if (ret) {
warn_report("Trying to enable capability %"PRIu64" of "
"KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 but failed. "
"Falling back to the legacy mode. ",
dirty_log_manual_caps);
s->manual_dirty_log_protect = 0;
}
}
}
#ifdef KVM_CAP_VCPU_EVENTS
s->vcpu_events = kvm_check_extension(s, KVM_CAP_VCPU_EVENTS);
#endif
s->robust_singlestep =
kvm_check_extension(s, KVM_CAP_X86_ROBUST_SINGLESTEP);
#ifdef KVM_CAP_DEBUGREGS
s->debugregs = kvm_check_extension(s, KVM_CAP_DEBUGREGS);
#endif
s->max_nested_state_len = kvm_check_extension(s, KVM_CAP_NESTED_STATE);
#ifdef KVM_CAP_IRQ_ROUTING
kvm_direct_msi_allowed = (kvm_check_extension(s, KVM_CAP_SIGNAL_MSI) > 0);
#endif
s->intx_set_mask = kvm_check_extension(s, KVM_CAP_PCI_2_3);
s->irq_set_ioctl = KVM_IRQ_LINE;
if (kvm_check_extension(s, KVM_CAP_IRQ_INJECT_STATUS)) {
s->irq_set_ioctl = KVM_IRQ_LINE_STATUS;
}
kvm_readonly_mem_allowed =
(kvm_check_extension(s, KVM_CAP_READONLY_MEM) > 0);
kvm_eventfds_allowed =
(kvm_check_extension(s, KVM_CAP_IOEVENTFD) > 0);
kvm_irqfds_allowed =
(kvm_check_extension(s, KVM_CAP_IRQFD) > 0);
kvm_resamplefds_allowed =
(kvm_check_extension(s, KVM_CAP_IRQFD_RESAMPLE) > 0);
kvm_vm_attributes_allowed =
(kvm_check_extension(s, KVM_CAP_VM_ATTRIBUTES) > 0);
kvm_ioeventfd_any_length_allowed =
(kvm_check_extension(s, KVM_CAP_IOEVENTFD_ANY_LENGTH) > 0);
#ifdef KVM_CAP_SET_GUEST_DEBUG
kvm_has_guest_debug =
(kvm_check_extension(s, KVM_CAP_SET_GUEST_DEBUG) > 0);
#endif
kvm_sstep_flags = 0;
if (kvm_has_guest_debug) {
kvm_sstep_flags = SSTEP_ENABLE;
#if defined KVM_CAP_SET_GUEST_DEBUG2
int guest_debug_flags =
kvm_check_extension(s, KVM_CAP_SET_GUEST_DEBUG2);
if (guest_debug_flags & KVM_GUESTDBG_BLOCKIRQ) {
kvm_sstep_flags |= SSTEP_NOIRQ;
}
#endif
}
kvm_state = s;
ret = kvm_arch_init(ms, s);
if (ret < 0) {
goto err;
}
if (s->kernel_irqchip_split == ON_OFF_AUTO_AUTO) {
s->kernel_irqchip_split = mc->default_kernel_irqchip_split ? ON_OFF_AUTO_ON : ON_OFF_AUTO_OFF;
}
qemu_register_reset(kvm_unpoison_all, NULL);
if (s->kernel_irqchip_allowed) {
kvm_irqchip_create(s);
}
if (kvm_eventfds_allowed) {
s->memory_listener.listener.eventfd_add = kvm_mem_ioeventfd_add;
s->memory_listener.listener.eventfd_del = kvm_mem_ioeventfd_del;
}
s->memory_listener.listener.coalesced_io_add = kvm_coalesce_mmio_region;
s->memory_listener.listener.coalesced_io_del = kvm_uncoalesce_mmio_region;
kvm_memory_listener_register(s, &s->memory_listener,
&address_space_memory, 0, "kvm-memory");
if (kvm_eventfds_allowed) {
memory_listener_register(&kvm_io_listener,
&address_space_io);
}
memory_listener_register(&kvm_coalesced_pio_listener,
&address_space_io);
s->many_ioeventfds = kvm_check_many_ioeventfds();
s->sync_mmu = !!kvm_vm_check_extension(kvm_state, KVM_CAP_SYNC_MMU);
if (!s->sync_mmu) {
ret = ram_block_discard_disable(true);
assert(!ret);
}
if (s->kvm_dirty_ring_size) {
ret = kvm_dirty_ring_reaper_init(s);
if (ret) {
goto err;
}
}
if (kvm_check_extension(kvm_state, KVM_CAP_BINARY_STATS_FD)) {
add_stats_callbacks(STATS_PROVIDER_KVM, query_stats_cb,
query_stats_schemas_cb);
}
return 0;
err:
assert(ret < 0);
if (s->vmfd >= 0) {
close(s->vmfd);
}
if (s->fd != -1) {
close(s->fd);
}
g_free(s->memory_listener.slots);
return ret;
}
void kvm_set_sigmask_len(KVMState *s, unsigned int sigmask_len)
{
s->sigmask_len = sigmask_len;
}
static void kvm_handle_io(uint16_t port, MemTxAttrs attrs, void *data, int direction,
int size, uint32_t count)
{
int i;
uint8_t *ptr = data;
for (i = 0; i < count; i++) {
address_space_rw(&address_space_io, port, attrs,
ptr, size,
direction == KVM_EXIT_IO_OUT);
ptr += size;
}
}
static int kvm_handle_internal_error(CPUState *cpu, struct kvm_run *run)
{
fprintf(stderr, "KVM internal error. Suberror: %d\n",
run->internal.suberror);
if (kvm_check_extension(kvm_state, KVM_CAP_INTERNAL_ERROR_DATA)) {
int i;
for (i = 0; i < run->internal.ndata; ++i) {
fprintf(stderr, "extra data[%d]: 0x%016"PRIx64"\n",
i, (uint64_t)run->internal.data[i]);
}
}
if (run->internal.suberror == KVM_INTERNAL_ERROR_EMULATION) {
fprintf(stderr, "emulation failure\n");
if (!kvm_arch_stop_on_emulation_error(cpu)) {
cpu_dump_state(cpu, stderr, CPU_DUMP_CODE);
return EXCP_INTERRUPT;
}
}
/* FIXME: Should trigger a qmp message to let management know
* something went wrong.
*/
return -1;
}
void kvm_flush_coalesced_mmio_buffer(void)
{
KVMState *s = kvm_state;
if (s->coalesced_flush_in_progress) {
return;
}
s->coalesced_flush_in_progress = true;
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];
if (ent->pio == 1) {
address_space_write(&address_space_io, ent->phys_addr,
MEMTXATTRS_UNSPECIFIED, ent->data,
ent->len);
} else {
cpu_physical_memory_write(ent->phys_addr, ent->data, ent->len);
}
smp_wmb();
ring->first = (ring->first + 1) % KVM_COALESCED_MMIO_MAX;
}
}
s->coalesced_flush_in_progress = false;
}
bool kvm_cpu_check_are_resettable(void)
{
return kvm_arch_cpu_check_are_resettable();
}
static void do_kvm_cpu_synchronize_state(CPUState *cpu, run_on_cpu_data arg)
{
if (!cpu->vcpu_dirty) {
kvm_arch_get_registers(cpu);
cpu->vcpu_dirty = true;
}
}
void kvm_cpu_synchronize_state(CPUState *cpu)
{
if (!cpu->vcpu_dirty) {
run_on_cpu(cpu, do_kvm_cpu_synchronize_state, RUN_ON_CPU_NULL);
}
}
static void do_kvm_cpu_synchronize_post_reset(CPUState *cpu, run_on_cpu_data arg)
{
kvm_arch_put_registers(cpu, KVM_PUT_RESET_STATE);
cpu->vcpu_dirty = false;
}
void kvm_cpu_synchronize_post_reset(CPUState *cpu)
{
run_on_cpu(cpu, do_kvm_cpu_synchronize_post_reset, RUN_ON_CPU_NULL);
}
static void do_kvm_cpu_synchronize_post_init(CPUState *cpu, run_on_cpu_data arg)
{
kvm_arch_put_registers(cpu, KVM_PUT_FULL_STATE);
cpu->vcpu_dirty = false;
}
void kvm_cpu_synchronize_post_init(CPUState *cpu)
{
run_on_cpu(cpu, do_kvm_cpu_synchronize_post_init, RUN_ON_CPU_NULL);
}
static void do_kvm_cpu_synchronize_pre_loadvm(CPUState *cpu, run_on_cpu_data arg)
{
cpu->vcpu_dirty = true;
}
void kvm_cpu_synchronize_pre_loadvm(CPUState *cpu)
{
run_on_cpu(cpu, do_kvm_cpu_synchronize_pre_loadvm, RUN_ON_CPU_NULL);
}
#ifdef KVM_HAVE_MCE_INJECTION
static __thread void *pending_sigbus_addr;
static __thread int pending_sigbus_code;
static __thread bool have_sigbus_pending;
#endif
static void kvm_cpu_kick(CPUState *cpu)
{
qatomic_set(&cpu->kvm_run->immediate_exit, 1);
}
static void kvm_cpu_kick_self(void)
{
if (kvm_immediate_exit) {
kvm_cpu_kick(current_cpu);
} else {
qemu_cpu_kick_self();
}
}
static void kvm_eat_signals(CPUState *cpu)
{
struct timespec ts = { 0, 0 };
siginfo_t siginfo;
sigset_t waitset;
sigset_t chkset;
int r;
if (kvm_immediate_exit) {
qatomic_set(&cpu->kvm_run->immediate_exit, 0);
/* Write kvm_run->immediate_exit before the cpu->exit_request
* write in kvm_cpu_exec.
*/
smp_wmb();
return;
}
sigemptyset(&waitset);
sigaddset(&waitset, SIG_IPI);
do {
r = sigtimedwait(&waitset, &siginfo, &ts);
if (r == -1 && !(errno == EAGAIN || errno == EINTR)) {
perror("sigtimedwait");
exit(1);
}
r = sigpending(&chkset);
if (r == -1) {
perror("sigpending");
exit(1);
}
} while (sigismember(&chkset, SIG_IPI));
}
int kvm_cpu_exec(CPUState *cpu)
{
struct kvm_run *run = cpu->kvm_run;
int ret, run_ret;
DPRINTF("kvm_cpu_exec()\n");
if (kvm_arch_process_async_events(cpu)) {
qatomic_set(&cpu->exit_request, 0);
return EXCP_HLT;
}
qemu_mutex_unlock_iothread();
cpu_exec_start(cpu);
do {
MemTxAttrs attrs;
if (cpu->vcpu_dirty) {
kvm_arch_put_registers(cpu, KVM_PUT_RUNTIME_STATE);
cpu->vcpu_dirty = false;
}
kvm_arch_pre_run(cpu, run);
if (qatomic_read(&cpu->exit_request)) {
DPRINTF("interrupt exit requested\n");
/*
* KVM requires us to reenter the kernel after IO exits to complete
* instruction emulation. This self-signal will ensure that we
* leave ASAP again.
*/
kvm_cpu_kick_self();
}
/* Read cpu->exit_request before KVM_RUN reads run->immediate_exit.
* Matching barrier in kvm_eat_signals.
*/
smp_rmb();
run_ret = kvm_vcpu_ioctl(cpu, KVM_RUN, 0);
attrs = kvm_arch_post_run(cpu, run);
#ifdef KVM_HAVE_MCE_INJECTION
if (unlikely(have_sigbus_pending)) {
qemu_mutex_lock_iothread();
kvm_arch_on_sigbus_vcpu(cpu, pending_sigbus_code,
pending_sigbus_addr);
have_sigbus_pending = false;
qemu_mutex_unlock_iothread();
}
#endif
if (run_ret < 0) {
if (run_ret == -EINTR || run_ret == -EAGAIN) {
DPRINTF("io window exit\n");
kvm_eat_signals(cpu);
ret = EXCP_INTERRUPT;
break;
}
fprintf(stderr, "error: kvm run failed %s\n",
strerror(-run_ret));
#ifdef TARGET_PPC
if (run_ret == -EBUSY) {
fprintf(stderr,
"This is probably because your SMT is enabled.\n"
"VCPU can only run on primary threads with all "
"secondary threads offline.\n");
}
#endif
ret = -1;
break;
}
trace_kvm_run_exit(cpu->cpu_index, run->exit_reason);
switch (run->exit_reason) {
case KVM_EXIT_IO:
DPRINTF("handle_io\n");
/* Called outside BQL */
kvm_handle_io(run->io.port, attrs,
(uint8_t *)run + run->io.data_offset,
run->io.direction,
run->io.size,
run->io.count);
ret = 0;
break;
case KVM_EXIT_MMIO:
DPRINTF("handle_mmio\n");
/* Called outside BQL */
address_space_rw(&address_space_memory,
run->mmio.phys_addr, attrs,
run->mmio.data,
run->mmio.len,
run->mmio.is_write);
ret = 0;
break;
case KVM_EXIT_IRQ_WINDOW_OPEN:
DPRINTF("irq_window_open\n");
ret = EXCP_INTERRUPT;
break;
case KVM_EXIT_SHUTDOWN:
DPRINTF("shutdown\n");
qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
ret = EXCP_INTERRUPT;
break;
case KVM_EXIT_UNKNOWN:
fprintf(stderr, "KVM: unknown exit, hardware reason %" PRIx64 "\n",
(uint64_t)run->hw.hardware_exit_reason);
ret = -1;
break;
case KVM_EXIT_INTERNAL_ERROR:
ret = kvm_handle_internal_error(cpu, run);
break;
case KVM_EXIT_DIRTY_RING_FULL:
/*
* We shouldn't continue if the dirty ring of this vcpu is
* still full. Got kicked by KVM_RESET_DIRTY_RINGS.
*/
trace_kvm_dirty_ring_full(cpu->cpu_index);
qemu_mutex_lock_iothread();
/*
* We throttle vCPU by making it sleep once it exit from kernel
* due to dirty ring full. In the dirtylimit scenario, reaping
* all vCPUs after a single vCPU dirty ring get full result in
* the miss of sleep, so just reap the ring-fulled vCPU.
*/
if (dirtylimit_in_service()) {
kvm_dirty_ring_reap(kvm_state, cpu);
} else {
kvm_dirty_ring_reap(kvm_state, NULL);
}
qemu_mutex_unlock_iothread();
dirtylimit_vcpu_execute(cpu);
ret = 0;
break;
case KVM_EXIT_SYSTEM_EVENT:
switch (run->system_event.type) {
case KVM_SYSTEM_EVENT_SHUTDOWN:
qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
ret = EXCP_INTERRUPT;
break;
case KVM_SYSTEM_EVENT_RESET:
qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
ret = EXCP_INTERRUPT;
break;
case KVM_SYSTEM_EVENT_CRASH:
kvm_cpu_synchronize_state(cpu);
qemu_mutex_lock_iothread();
qemu_system_guest_panicked(cpu_get_crash_info(cpu));
qemu_mutex_unlock_iothread();
ret = 0;
break;
default:
DPRINTF("kvm_arch_handle_exit\n");
ret = kvm_arch_handle_exit(cpu, run);
break;
}
break;
default:
DPRINTF("kvm_arch_handle_exit\n");
ret = kvm_arch_handle_exit(cpu, run);
break;
}
} while (ret == 0);
cpu_exec_end(cpu);
qemu_mutex_lock_iothread();
if (ret < 0) {
cpu_dump_state(cpu, stderr, CPU_DUMP_CODE);
vm_stop(RUN_STATE_INTERNAL_ERROR);
}
qatomic_set(&cpu->exit_request, 0);
return ret;
}
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);
trace_kvm_ioctl(type, arg);
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);
trace_kvm_vm_ioctl(type, arg);
ret = ioctl(s->vmfd, type, arg);
if (ret == -1) {
ret = -errno;
}
return ret;
}
int kvm_vcpu_ioctl(CPUState *cpu, int type, ...)
{
int ret;
void *arg;
va_list ap;
va_start(ap, type);
arg = va_arg(ap, void *);
va_end(ap);
trace_kvm_vcpu_ioctl(cpu->cpu_index, type, arg);
ret = ioctl(cpu->kvm_fd, type, arg);
if (ret == -1) {
ret = -errno;
}
return ret;
}
int kvm_device_ioctl(int fd, int type, ...)
{
int ret;
void *arg;
va_list ap;
va_start(ap, type);
arg = va_arg(ap, void *);
va_end(ap);
trace_kvm_device_ioctl(fd, type, arg);
ret = ioctl(fd, type, arg);
if (ret == -1) {
ret = -errno;
}
return ret;
}
int kvm_vm_check_attr(KVMState *s, uint32_t group, uint64_t attr)
{
int ret;
struct kvm_device_attr attribute = {
.group = group,
.attr = attr,
};
if (!kvm_vm_attributes_allowed) {
return 0;
}
ret = kvm_vm_ioctl(s, KVM_HAS_DEVICE_ATTR, &attribute);
/* kvm returns 0 on success for HAS_DEVICE_ATTR */
return ret ? 0 : 1;
}
int kvm_device_check_attr(int dev_fd, uint32_t group, uint64_t attr)
{
struct kvm_device_attr attribute = {
.group = group,
.attr = attr,
.flags = 0,
};
return kvm_device_ioctl(dev_fd, KVM_HAS_DEVICE_ATTR, &attribute) ? 0 : 1;
}
int kvm_device_access(int fd, int group, uint64_t attr,
void *val, bool write, Error **errp)
{
struct kvm_device_attr kvmattr;
int err;
kvmattr.flags = 0;
kvmattr.group = group;
kvmattr.attr = attr;
kvmattr.addr = (uintptr_t)val;
err = kvm_device_ioctl(fd,
write ? KVM_SET_DEVICE_ATTR : KVM_GET_DEVICE_ATTR,
&kvmattr);
if (err < 0) {
error_setg_errno(errp, -err,
"KVM_%s_DEVICE_ATTR failed: Group %d "
"attr 0x%016" PRIx64,
write ? "SET" : "GET", group, attr);
}
return err;
}
bool kvm_has_sync_mmu(void)
{
return kvm_state->sync_mmu;
}
int kvm_has_vcpu_events(void)
{
return kvm_state->vcpu_events;
}
int kvm_has_robust_singlestep(void)
{
return kvm_state->robust_singlestep;
}
int kvm_has_debugregs(void)
{
return kvm_state->debugregs;
}
int kvm_max_nested_state_length(void)
{
return kvm_state->max_nested_state_len;
}
int kvm_has_many_ioeventfds(void)
{
if (!kvm_enabled()) {
return 0;
}
return kvm_state->many_ioeventfds;
}
int kvm_has_gsi_routing(void)
{
#ifdef KVM_CAP_IRQ_ROUTING
return kvm_check_extension(kvm_state, KVM_CAP_IRQ_ROUTING);
#else
return false;
#endif
}
int kvm_has_intx_set_mask(void)
{
return kvm_state->intx_set_mask;
}
bool kvm_arm_supports_user_irq(void)
{
return kvm_check_extension(kvm_state, KVM_CAP_ARM_USER_IRQ);
}
#ifdef KVM_CAP_SET_GUEST_DEBUG
struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *cpu,
target_ulong pc)
{
struct kvm_sw_breakpoint *bp;
QTAILQ_FOREACH(bp, &cpu->kvm_state->kvm_sw_breakpoints, entry) {
if (bp->pc == pc) {
return bp;
}
}
return NULL;
}
int kvm_sw_breakpoints_active(CPUState *cpu)
{
return !QTAILQ_EMPTY(&cpu->kvm_state->kvm_sw_breakpoints);
}
struct kvm_set_guest_debug_data {
struct kvm_guest_debug dbg;
int err;
};
static void kvm_invoke_set_guest_debug(CPUState *cpu, run_on_cpu_data data)
{
struct kvm_set_guest_debug_data *dbg_data =
(struct kvm_set_guest_debug_data *) data.host_ptr;
dbg_data->err = kvm_vcpu_ioctl(cpu, KVM_SET_GUEST_DEBUG,
&dbg_data->dbg);
}
int kvm_update_guest_debug(CPUState *cpu, unsigned long reinject_trap)
{
struct kvm_set_guest_debug_data data;
data.dbg.control = reinject_trap;
if (cpu->singlestep_enabled) {
data.dbg.control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP;
if (cpu->singlestep_enabled & SSTEP_NOIRQ) {
data.dbg.control |= KVM_GUESTDBG_BLOCKIRQ;
}
}
kvm_arch_update_guest_debug(cpu, &data.dbg);
run_on_cpu(cpu, kvm_invoke_set_guest_debug,
RUN_ON_CPU_HOST_PTR(&data));
return data.err;
}
bool kvm_supports_guest_debug(void)
{
/* probed during kvm_init() */
return kvm_has_guest_debug;
}
int kvm_insert_breakpoint(CPUState *cpu, int type, hwaddr addr, hwaddr len)
{
struct kvm_sw_breakpoint *bp;
int err;
if (type == GDB_BREAKPOINT_SW) {
bp = kvm_find_sw_breakpoint(cpu, addr);
if (bp) {
bp->use_count++;
return 0;
}
bp = g_new(struct kvm_sw_breakpoint, 1);
bp->pc = addr;
bp->use_count = 1;
err = kvm_arch_insert_sw_breakpoint(cpu, bp);
if (err) {
g_free(bp);
return err;
}
QTAILQ_INSERT_HEAD(&cpu->kvm_state->kvm_sw_breakpoints, bp, entry);
} else {
err = kvm_arch_insert_hw_breakpoint(addr, len, type);
if (err) {
return err;
}
}
CPU_FOREACH(cpu) {
err = kvm_update_guest_debug(cpu, 0);
if (err) {
return err;
}
}
return 0;
}
int kvm_remove_breakpoint(CPUState *cpu, int type, hwaddr addr, hwaddr len)
{
struct kvm_sw_breakpoint *bp;
int err;
if (type == GDB_BREAKPOINT_SW) {
bp = kvm_find_sw_breakpoint(cpu, addr);
if (!bp) {
return -ENOENT;
}
if (bp->use_count > 1) {
bp->use_count--;
return 0;
}
err = kvm_arch_remove_sw_breakpoint(cpu, bp);
if (err) {
return err;
}
QTAILQ_REMOVE(&cpu->kvm_state->kvm_sw_breakpoints, bp, entry);
g_free(bp);
} else {
err = kvm_arch_remove_hw_breakpoint(addr, len, type);
if (err) {
return err;
}
}
CPU_FOREACH(cpu) {
err = kvm_update_guest_debug(cpu, 0);
if (err) {
return err;
}
}
return 0;
}
void kvm_remove_all_breakpoints(CPUState *cpu)
{
struct kvm_sw_breakpoint *bp, *next;
KVMState *s = cpu->kvm_state;
CPUState *tmpcpu;
QTAILQ_FOREACH_SAFE(bp, &s->kvm_sw_breakpoints, entry, next) {
if (kvm_arch_remove_sw_breakpoint(cpu, bp) != 0) {
/* Try harder to find a CPU that currently sees the breakpoint. */
CPU_FOREACH(tmpcpu) {
if (kvm_arch_remove_sw_breakpoint(tmpcpu, bp) == 0) {
break;
}
}
}
QTAILQ_REMOVE(&s->kvm_sw_breakpoints, bp, entry);
g_free(bp);
}
kvm_arch_remove_all_hw_breakpoints();
CPU_FOREACH(cpu) {
kvm_update_guest_debug(cpu, 0);
}
}
#endif /* !KVM_CAP_SET_GUEST_DEBUG */
static int kvm_set_signal_mask(CPUState *cpu, const sigset_t *sigset)
{
KVMState *s = kvm_state;
struct kvm_signal_mask *sigmask;
int r;
sigmask = g_malloc(sizeof(*sigmask) + sizeof(*sigset));
sigmask->len = s->sigmask_len;
memcpy(sigmask->sigset, sigset, sizeof(*sigset));
r = kvm_vcpu_ioctl(cpu, KVM_SET_SIGNAL_MASK, sigmask);
g_free(sigmask);
return r;
}
static void kvm_ipi_signal(int sig)
{
if (current_cpu) {
assert(kvm_immediate_exit);
kvm_cpu_kick(current_cpu);
}
}
void kvm_init_cpu_signals(CPUState *cpu)
{
int r;
sigset_t set;
struct sigaction sigact;
memset(&sigact, 0, sizeof(sigact));
sigact.sa_handler = kvm_ipi_signal;
sigaction(SIG_IPI, &sigact, NULL);
pthread_sigmask(SIG_BLOCK, NULL, &set);
#if defined KVM_HAVE_MCE_INJECTION
sigdelset(&set, SIGBUS);
pthread_sigmask(SIG_SETMASK, &set, NULL);
#endif
sigdelset(&set, SIG_IPI);
if (kvm_immediate_exit) {
r = pthread_sigmask(SIG_SETMASK, &set, NULL);
} else {
r = kvm_set_signal_mask(cpu, &set);
}
if (r) {
fprintf(stderr, "kvm_set_signal_mask: %s\n", strerror(-r));
exit(1);
}
}
/* Called asynchronously in VCPU thread. */
int kvm_on_sigbus_vcpu(CPUState *cpu, int code, void *addr)
{
#ifdef KVM_HAVE_MCE_INJECTION
if (have_sigbus_pending) {
return 1;
}
have_sigbus_pending = true;
pending_sigbus_addr = addr;
pending_sigbus_code = code;
qatomic_set(&cpu->exit_request, 1);
return 0;
#else
return 1;
#endif
}
/* Called synchronously (via signalfd) in main thread. */
int kvm_on_sigbus(int code, void *addr)
{
#ifdef KVM_HAVE_MCE_INJECTION
/* Action required MCE kills the process if SIGBUS is blocked. Because
* that's what happens in the I/O thread, where we handle MCE via signalfd,
* we can only get action optional here.
*/
assert(code != BUS_MCEERR_AR);
kvm_arch_on_sigbus_vcpu(first_cpu, code, addr);
return 0;
#else
return 1;
#endif
}
int kvm_create_device(KVMState *s, uint64_t type, bool test)
{
int ret;
struct kvm_create_device create_dev;
create_dev.type = type;
create_dev.fd = -1;
create_dev.flags = test ? KVM_CREATE_DEVICE_TEST : 0;
if (!kvm_check_extension(s, KVM_CAP_DEVICE_CTRL)) {
return -ENOTSUP;
}
ret = kvm_vm_ioctl(s, KVM_CREATE_DEVICE, &create_dev);
if (ret) {
return ret;
}
return test ? 0 : create_dev.fd;
}
bool kvm_device_supported(int vmfd, uint64_t type)
{
struct kvm_create_device create_dev = {
.type = type,
.fd = -1,
.flags = KVM_CREATE_DEVICE_TEST,
};
if (ioctl(vmfd, KVM_CHECK_EXTENSION, KVM_CAP_DEVICE_CTRL) <= 0) {
return false;
}
return (ioctl(vmfd, KVM_CREATE_DEVICE, &create_dev) >= 0);
}
int kvm_set_one_reg(CPUState *cs, uint64_t id, void *source)
{
struct kvm_one_reg reg;
int r;
reg.id = id;
reg.addr = (uintptr_t) source;
r = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
if (r) {
trace_kvm_failed_reg_set(id, strerror(-r));
}
return r;
}
int kvm_get_one_reg(CPUState *cs, uint64_t id, void *target)
{
struct kvm_one_reg reg;
int r;
reg.id = id;
reg.addr = (uintptr_t) target;
r = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
if (r) {
trace_kvm_failed_reg_get(id, strerror(-r));
}
return r;
}
static bool kvm_accel_has_memory(MachineState *ms, AddressSpace *as,
hwaddr start_addr, hwaddr size)
{
KVMState *kvm = KVM_STATE(ms->accelerator);
int i;
for (i = 0; i < kvm->nr_as; ++i) {
if (kvm->as[i].as == as && kvm->as[i].ml) {
size = MIN(kvm_max_slot_size, size);
return NULL != kvm_lookup_matching_slot(kvm->as[i].ml,
start_addr, size);
}
}
return false;
}
static void kvm_get_kvm_shadow_mem(Object *obj, Visitor *v,
const char *name, void *opaque,
Error **errp)
{
KVMState *s = KVM_STATE(obj);
int64_t value = s->kvm_shadow_mem;
visit_type_int(v, name, &value, errp);
}
static void kvm_set_kvm_shadow_mem(Object *obj, Visitor *v,
const char *name, void *opaque,
Error **errp)
{
KVMState *s = KVM_STATE(obj);
int64_t value;
if (s->fd != -1) {
error_setg(errp, "Cannot set properties after the accelerator has been initialized");
return;
}
if (!visit_type_int(v, name, &value, errp)) {
return;
}
s->kvm_shadow_mem = value;
}
static void kvm_set_kernel_irqchip(Object *obj, Visitor *v,
const char *name, void *opaque,
Error **errp)
{
KVMState *s = KVM_STATE(obj);
OnOffSplit mode;
if (s->fd != -1) {
error_setg(errp, "Cannot set properties after the accelerator has been initialized");
return;
}
if (!visit_type_OnOffSplit(v, name, &mode, errp)) {
return;
}
switch (mode) {
case ON_OFF_SPLIT_ON:
s->kernel_irqchip_allowed = true;
s->kernel_irqchip_required = true;
s->kernel_irqchip_split = ON_OFF_AUTO_OFF;
break;
case ON_OFF_SPLIT_OFF:
s->kernel_irqchip_allowed = false;
s->kernel_irqchip_required = false;
s->kernel_irqchip_split = ON_OFF_AUTO_OFF;
break;
case ON_OFF_SPLIT_SPLIT:
s->kernel_irqchip_allowed = true;
s->kernel_irqchip_required = true;
s->kernel_irqchip_split = ON_OFF_AUTO_ON;
break;
default:
/* The value was checked in visit_type_OnOffSplit() above. If
* we get here, then something is wrong in QEMU.
*/
abort();
}
}
bool kvm_kernel_irqchip_allowed(void)
{
return kvm_state->kernel_irqchip_allowed;
}
bool kvm_kernel_irqchip_required(void)
{
return kvm_state->kernel_irqchip_required;
}
bool kvm_kernel_irqchip_split(void)
{
return kvm_state->kernel_irqchip_split == ON_OFF_AUTO_ON;
}
static void kvm_get_dirty_ring_size(Object *obj, Visitor *v,
const char *name, void *opaque,
Error **errp)
{
KVMState *s = KVM_STATE(obj);
uint32_t value = s->kvm_dirty_ring_size;
visit_type_uint32(v, name, &value, errp);
}
static void kvm_set_dirty_ring_size(Object *obj, Visitor *v,
const char *name, void *opaque,
Error **errp)
{
KVMState *s = KVM_STATE(obj);
Error *error = NULL;
uint32_t value;
if (s->fd != -1) {
error_setg(errp, "Cannot set properties after the accelerator has been initialized");
return;
}
visit_type_uint32(v, name, &value, &error);
if (error) {
error_propagate(errp, error);
return;
}
if (value & (value - 1)) {
error_setg(errp, "dirty-ring-size must be a power of two.");
return;
}
s->kvm_dirty_ring_size = value;
}
static void kvm_accel_instance_init(Object *obj)
{
KVMState *s = KVM_STATE(obj);
s->fd = -1;
s->vmfd = -1;
s->kvm_shadow_mem = -1;
s->kernel_irqchip_allowed = true;
s->kernel_irqchip_split = ON_OFF_AUTO_AUTO;
/* KVM dirty ring is by default off */
s->kvm_dirty_ring_size = 0;
s->notify_vmexit = NOTIFY_VMEXIT_OPTION_RUN;
s->notify_window = 0;
}
/**
* kvm_gdbstub_sstep_flags():
*
* Returns: SSTEP_* flags that KVM supports for guest debug. The
* support is probed during kvm_init()
*/
static int kvm_gdbstub_sstep_flags(void)
{
return kvm_sstep_flags;
}
static void kvm_accel_class_init(ObjectClass *oc, void *data)
{
AccelClass *ac = ACCEL_CLASS(oc);
ac->name = "KVM";
ac->init_machine = kvm_init;
ac->has_memory = kvm_accel_has_memory;
ac->allowed = &kvm_allowed;
ac->gdbstub_supported_sstep_flags = kvm_gdbstub_sstep_flags;
object_class_property_add(oc, "kernel-irqchip", "on|off|split",
NULL, kvm_set_kernel_irqchip,
NULL, NULL);
object_class_property_set_description(oc, "kernel-irqchip",
"Configure KVM in-kernel irqchip");
object_class_property_add(oc, "kvm-shadow-mem", "int",
kvm_get_kvm_shadow_mem, kvm_set_kvm_shadow_mem,
NULL, NULL);
object_class_property_set_description(oc, "kvm-shadow-mem",
"KVM shadow MMU size");
object_class_property_add(oc, "dirty-ring-size", "uint32",
kvm_get_dirty_ring_size, kvm_set_dirty_ring_size,
NULL, NULL);
object_class_property_set_description(oc, "dirty-ring-size",
"Size of KVM dirty page ring buffer (default: 0, i.e. use bitmap)");
kvm_arch_accel_class_init(oc);
}
static const TypeInfo kvm_accel_type = {
.name = TYPE_KVM_ACCEL,
.parent = TYPE_ACCEL,
.instance_init = kvm_accel_instance_init,
.class_init = kvm_accel_class_init,
.instance_size = sizeof(KVMState),
};
static void kvm_type_init(void)
{
type_register_static(&kvm_accel_type);
}
type_init(kvm_type_init);
typedef struct StatsArgs {
union StatsResultsType {
StatsResultList **stats;
StatsSchemaList **schema;
} result;
strList *names;
Error **errp;
} StatsArgs;
static StatsList *add_kvmstat_entry(struct kvm_stats_desc *pdesc,
uint64_t *stats_data,
StatsList *stats_list,
Error **errp)
{
Stats *stats;
uint64List *val_list = NULL;
/* Only add stats that we understand. */
switch (pdesc->flags & KVM_STATS_TYPE_MASK) {
case KVM_STATS_TYPE_CUMULATIVE:
case KVM_STATS_TYPE_INSTANT:
case KVM_STATS_TYPE_PEAK:
case KVM_STATS_TYPE_LINEAR_HIST:
case KVM_STATS_TYPE_LOG_HIST:
break;
default:
return stats_list;
}
switch (pdesc->flags & KVM_STATS_UNIT_MASK) {
case KVM_STATS_UNIT_NONE:
case KVM_STATS_UNIT_BYTES:
case KVM_STATS_UNIT_CYCLES:
case KVM_STATS_UNIT_SECONDS:
case KVM_STATS_UNIT_BOOLEAN:
break;
default:
return stats_list;
}
switch (pdesc->flags & KVM_STATS_BASE_MASK) {
case KVM_STATS_BASE_POW10:
case KVM_STATS_BASE_POW2:
break;
default:
return stats_list;
}
/* Alloc and populate data list */
stats = g_new0(Stats, 1);
stats->name = g_strdup(pdesc->name);
stats->value = g_new0(StatsValue, 1);;
if ((pdesc->flags & KVM_STATS_UNIT_MASK) == KVM_STATS_UNIT_BOOLEAN) {
stats->value->u.boolean = *stats_data;
stats->value->type = QTYPE_QBOOL;
} else if (pdesc->size == 1) {
stats->value->u.scalar = *stats_data;
stats->value->type = QTYPE_QNUM;
} else {
int i;
for (i = 0; i < pdesc->size; i++) {
QAPI_LIST_PREPEND(val_list, stats_data[i]);
}
stats->value->u.list = val_list;
stats->value->type = QTYPE_QLIST;
}
QAPI_LIST_PREPEND(stats_list, stats);
return stats_list;
}
static StatsSchemaValueList *add_kvmschema_entry(struct kvm_stats_desc *pdesc,
StatsSchemaValueList *list,
Error **errp)
{
StatsSchemaValueList *schema_entry = g_new0(StatsSchemaValueList, 1);
schema_entry->value = g_new0(StatsSchemaValue, 1);
switch (pdesc->flags & KVM_STATS_TYPE_MASK) {
case KVM_STATS_TYPE_CUMULATIVE:
schema_entry->value->type = STATS_TYPE_CUMULATIVE;
break;
case KVM_STATS_TYPE_INSTANT:
schema_entry->value->type = STATS_TYPE_INSTANT;
break;
case KVM_STATS_TYPE_PEAK:
schema_entry->value->type = STATS_TYPE_PEAK;
break;
case KVM_STATS_TYPE_LINEAR_HIST:
schema_entry->value->type = STATS_TYPE_LINEAR_HISTOGRAM;
schema_entry->value->bucket_size = pdesc->bucket_size;
schema_entry->value->has_bucket_size = true;
break;
case KVM_STATS_TYPE_LOG_HIST:
schema_entry->value->type = STATS_TYPE_LOG2_HISTOGRAM;
break;
default:
goto exit;
}
switch (pdesc->flags & KVM_STATS_UNIT_MASK) {
case KVM_STATS_UNIT_NONE:
break;
case KVM_STATS_UNIT_BOOLEAN:
schema_entry->value->has_unit = true;
schema_entry->value->unit = STATS_UNIT_BOOLEAN;
break;
case KVM_STATS_UNIT_BYTES:
schema_entry->value->has_unit = true;
schema_entry->value->unit = STATS_UNIT_BYTES;
break;
case KVM_STATS_UNIT_CYCLES:
schema_entry->value->has_unit = true;
schema_entry->value->unit = STATS_UNIT_CYCLES;
break;
case KVM_STATS_UNIT_SECONDS:
schema_entry->value->has_unit = true;
schema_entry->value->unit = STATS_UNIT_SECONDS;
break;
default:
goto exit;
}
schema_entry->value->exponent = pdesc->exponent;
if (pdesc->exponent) {
switch (pdesc->flags & KVM_STATS_BASE_MASK) {
case KVM_STATS_BASE_POW10:
schema_entry->value->has_base = true;
schema_entry->value->base = 10;
break;
case KVM_STATS_BASE_POW2:
schema_entry->value->has_base = true;
schema_entry->value->base = 2;
break;
default:
goto exit;
}
}
schema_entry->value->name = g_strdup(pdesc->name);
schema_entry->next = list;
return schema_entry;
exit:
g_free(schema_entry->value);
g_free(schema_entry);
return list;
}
/* Cached stats descriptors */
typedef struct StatsDescriptors {
const char *ident; /* cache key, currently the StatsTarget */
struct kvm_stats_desc *kvm_stats_desc;
struct kvm_stats_header kvm_stats_header;
QTAILQ_ENTRY(StatsDescriptors) next;
} StatsDescriptors;
static QTAILQ_HEAD(, StatsDescriptors) stats_descriptors =
QTAILQ_HEAD_INITIALIZER(stats_descriptors);
/*
* Return the descriptors for 'target', that either have already been read
* or are retrieved from 'stats_fd'.
*/
static StatsDescriptors *find_stats_descriptors(StatsTarget target, int stats_fd,
Error **errp)
{
StatsDescriptors *descriptors;
const char *ident;
struct kvm_stats_desc *kvm_stats_desc;
struct kvm_stats_header *kvm_stats_header;
size_t size_desc;
ssize_t ret;
ident = StatsTarget_str(target);
QTAILQ_FOREACH(descriptors, &stats_descriptors, next) {
if (g_str_equal(descriptors->ident, ident)) {
return descriptors;
}
}
descriptors = g_new0(StatsDescriptors, 1);
/* Read stats header */
kvm_stats_header = &descriptors->kvm_stats_header;
ret = read(stats_fd, kvm_stats_header, sizeof(*kvm_stats_header));
if (ret != sizeof(*kvm_stats_header)) {
error_setg(errp, "KVM stats: failed to read stats header: "
"expected %zu actual %zu",
sizeof(*kvm_stats_header), ret);
g_free(descriptors);
return NULL;
}
size_desc = sizeof(*kvm_stats_desc) + kvm_stats_header->name_size;
/* Read stats descriptors */
kvm_stats_desc = g_malloc0_n(kvm_stats_header->num_desc, size_desc);
ret = pread(stats_fd, kvm_stats_desc,
size_desc * kvm_stats_header->num_desc,
kvm_stats_header->desc_offset);
if (ret != size_desc * kvm_stats_header->num_desc) {
error_setg(errp, "KVM stats: failed to read stats descriptors: "
"expected %zu actual %zu",
size_desc * kvm_stats_header->num_desc, ret);
g_free(descriptors);
g_free(kvm_stats_desc);
return NULL;
}
descriptors->kvm_stats_desc = kvm_stats_desc;
descriptors->ident = ident;
QTAILQ_INSERT_TAIL(&stats_descriptors, descriptors, next);
return descriptors;
}
static void query_stats(StatsResultList **result, StatsTarget target,
strList *names, int stats_fd, Error **errp)
{
struct kvm_stats_desc *kvm_stats_desc;
struct kvm_stats_header *kvm_stats_header;
StatsDescriptors *descriptors;
g_autofree uint64_t *stats_data = NULL;
struct kvm_stats_desc *pdesc;
StatsList *stats_list = NULL;
size_t size_desc, size_data = 0;
ssize_t ret;
int i;
descriptors = find_stats_descriptors(target, stats_fd, errp);
if (!descriptors) {
return;
}
kvm_stats_header = &descriptors->kvm_stats_header;
kvm_stats_desc = descriptors->kvm_stats_desc;
size_desc = sizeof(*kvm_stats_desc) + kvm_stats_header->name_size;
/* Tally the total data size; read schema data */
for (i = 0; i < kvm_stats_header->num_desc; ++i) {
pdesc = (void *)kvm_stats_desc + i * size_desc;
size_data += pdesc->size * sizeof(*stats_data);
}
stats_data = g_malloc0(size_data);
ret = pread(stats_fd, stats_data, size_data, kvm_stats_header->data_offset);
if (ret != size_data) {
error_setg(errp, "KVM stats: failed to read data: "
"expected %zu actual %zu", size_data, ret);
return;
}
for (i = 0; i < kvm_stats_header->num_desc; ++i) {
uint64_t *stats;
pdesc = (void *)kvm_stats_desc + i * size_desc;
/* Add entry to the list */
stats = (void *)stats_data + pdesc->offset;
if (!apply_str_list_filter(pdesc->name, names)) {
continue;
}
stats_list = add_kvmstat_entry(pdesc, stats, stats_list, errp);
}
if (!stats_list) {
return;
}
switch (target) {
case STATS_TARGET_VM:
add_stats_entry(result, STATS_PROVIDER_KVM, NULL, stats_list);
break;
case STATS_TARGET_VCPU:
add_stats_entry(result, STATS_PROVIDER_KVM,
current_cpu->parent_obj.canonical_path,
stats_list);
break;
default:
g_assert_not_reached();
}
}
static void query_stats_schema(StatsSchemaList **result, StatsTarget target,
int stats_fd, Error **errp)
{
struct kvm_stats_desc *kvm_stats_desc;
struct kvm_stats_header *kvm_stats_header;
StatsDescriptors *descriptors;
struct kvm_stats_desc *pdesc;
StatsSchemaValueList *stats_list = NULL;
size_t size_desc;
int i;
descriptors = find_stats_descriptors(target, stats_fd, errp);
if (!descriptors) {
return;
}
kvm_stats_header = &descriptors->kvm_stats_header;
kvm_stats_desc = descriptors->kvm_stats_desc;
size_desc = sizeof(*kvm_stats_desc) + kvm_stats_header->name_size;
/* Tally the total data size; read schema data */
for (i = 0; i < kvm_stats_header->num_desc; ++i) {
pdesc = (void *)kvm_stats_desc + i * size_desc;
stats_list = add_kvmschema_entry(pdesc, stats_list, errp);
}
add_stats_schema(result, STATS_PROVIDER_KVM, target, stats_list);
}
static void query_stats_vcpu(CPUState *cpu, run_on_cpu_data data)
{
StatsArgs *kvm_stats_args = (StatsArgs *) data.host_ptr;
int stats_fd = kvm_vcpu_ioctl(cpu, KVM_GET_STATS_FD, NULL);
Error *local_err = NULL;
if (stats_fd == -1) {
error_setg_errno(&local_err, errno, "KVM stats: ioctl failed");
error_propagate(kvm_stats_args->errp, local_err);
return;
}
query_stats(kvm_stats_args->result.stats, STATS_TARGET_VCPU,
kvm_stats_args->names, stats_fd, kvm_stats_args->errp);
close(stats_fd);
}
static void query_stats_schema_vcpu(CPUState *cpu, run_on_cpu_data data)
{
StatsArgs *kvm_stats_args = (StatsArgs *) data.host_ptr;
int stats_fd = kvm_vcpu_ioctl(cpu, KVM_GET_STATS_FD, NULL);
Error *local_err = NULL;
if (stats_fd == -1) {
error_setg_errno(&local_err, errno, "KVM stats: ioctl failed");
error_propagate(kvm_stats_args->errp, local_err);
return;
}
query_stats_schema(kvm_stats_args->result.schema, STATS_TARGET_VCPU, stats_fd,
kvm_stats_args->errp);
close(stats_fd);
}
static void query_stats_cb(StatsResultList **result, StatsTarget target,
strList *names, strList *targets, Error **errp)
{
KVMState *s = kvm_state;
CPUState *cpu;
int stats_fd;
switch (target) {
case STATS_TARGET_VM:
{
stats_fd = kvm_vm_ioctl(s, KVM_GET_STATS_FD, NULL);
if (stats_fd == -1) {
error_setg_errno(errp, errno, "KVM stats: ioctl failed");
return;
}
query_stats(result, target, names, stats_fd, errp);
close(stats_fd);
break;
}
case STATS_TARGET_VCPU:
{
StatsArgs stats_args;
stats_args.result.stats = result;
stats_args.names = names;
stats_args.errp = errp;
CPU_FOREACH(cpu) {
if (!apply_str_list_filter(cpu->parent_obj.canonical_path, targets)) {
continue;
}
run_on_cpu(cpu, query_stats_vcpu, RUN_ON_CPU_HOST_PTR(&stats_args));
}
break;
}
default:
break;
}
}
void query_stats_schemas_cb(StatsSchemaList **result, Error **errp)
{
StatsArgs stats_args;
KVMState *s = kvm_state;
int stats_fd;
stats_fd = kvm_vm_ioctl(s, KVM_GET_STATS_FD, NULL);
if (stats_fd == -1) {
error_setg_errno(errp, errno, "KVM stats: ioctl failed");
return;
}
query_stats_schema(result, STATS_TARGET_VM, stats_fd, errp);
close(stats_fd);
if (first_cpu) {
stats_args.result.schema = result;
stats_args.errp = errp;
run_on_cpu(first_cpu, query_stats_schema_vcpu, RUN_ON_CPU_HOST_PTR(&stats_args));
}
}