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qemu/accel/kvm/kvm-all.c
Peter Xu dcafa24827 KVM: Fix dirty ring mmap incorrect size due to renaming accident 
Found this when I wanted to try the per-vcpu dirty rate series out, then I
found that it's not really working and it can quickly hang death a guest.  I
found strange errors (e.g. guest crash after migration) happens even without
the per-vcpu dirty rate series.

When merging dirty ring, probably no one notice that the trivial renaming diff
[1] missed two existing references of kvm_dirty_ring_sizes; they do matter
since otherwise we'll mmap() a shorter range of memory after the renaming.

I think it didn't SIGBUS for me easily simply because some other stuff within
qemu mmap()ed right after the dirty rings (e.g. when testing 4096 slots, it
aligned with one small page on x86), so when we access the rings we've been
reading/writting to random memory elsewhere of qemu.

Fix the two sizes when map/unmap the shared dirty gfn memory.

[1] https://lore.kernel.org/qemu-devel/dac5f0c6-1bca-3daf-e5d2-6451dbbaca93@redhat.com/

Cc: Hyman Huang <huangy81@chinatelecom.cn>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210609014355.217110-1-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-06-25 10:54:12 +02:00

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/*
* QEMU KVM support
*
* Copyright IBM, Corp. 2008
* Red Hat, Inc. 2008
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
* Glauber Costa <gcosta@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#include "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 "hw/boards.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
//#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
#define KVM_MSI_HASHTAB_SIZE 256
struct KVMParkedVcpu {
unsigned long vcpu_id;
int kvm_fd;
QLIST_ENTRY(KVMParkedVcpu) node;
};
enum KVMDirtyRingReaperState {
KVM_DIRTY_RING_REAPER_NONE = 0,
/* The reaper is sleeping */
KVM_DIRTY_RING_REAPER_WAIT,
/* The reaper is reaping for dirty pages */
KVM_DIRTY_RING_REAPER_REAPING,
};
/*
* KVM reaper instance, responsible for collecting the KVM dirty bits
* via the dirty ring.
*/
struct KVMDirtyRingReaper {
/* The reaper thread */
QemuThread reaper_thr;
volatile uint64_t reaper_iteration; /* iteration number of reaper thr */
volatile enum KVMDirtyRingReaperState reaper_state; /* reap thr state */
};
struct KVMState
{
AccelState parent_obj;
int nr_slots;
int fd;
int vmfd;
int coalesced_mmio;
int coalesced_pio;
struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
bool coalesced_flush_in_progress;
int vcpu_events;
int robust_singlestep;
int debugregs;
#ifdef KVM_CAP_SET_GUEST_DEBUG
QTAILQ_HEAD(, kvm_sw_breakpoint) kvm_sw_breakpoints;
#endif
int max_nested_state_len;
int many_ioeventfds;
int intx_set_mask;
int kvm_shadow_mem;
bool kernel_irqchip_allowed;
bool kernel_irqchip_required;
OnOffAuto kernel_irqchip_split;
bool sync_mmu;
uint64_t manual_dirty_log_protect;
/* The man page (and posix) say ioctl numbers are signed int, but
* they're not. Linux, glibc and *BSD all treat ioctl numbers as
* unsigned, and treating them as signed here can break things */
unsigned irq_set_ioctl;
unsigned int sigmask_len;
GHashTable *gsimap;
#ifdef KVM_CAP_IRQ_ROUTING
struct kvm_irq_routing *irq_routes;
int nr_allocated_irq_routes;
unsigned long *used_gsi_bitmap;
unsigned int gsi_count;
QTAILQ_HEAD(, KVMMSIRoute) msi_hashtab[KVM_MSI_HASHTAB_SIZE];
#endif
KVMMemoryListener memory_listener;
QLIST_HEAD(, KVMParkedVcpu) kvm_parked_vcpus;
/* For "info mtree -f" to tell if an MR is registered in KVM */
int nr_as;
struct KVMAs {
KVMMemoryListener *ml;
AddressSpace *as;
} *as;
uint64_t kvm_dirty_ring_bytes; /* Size of the per-vcpu dirty ring */
uint32_t kvm_dirty_ring_size; /* Number of dirty GFNs per ring */
struct KVMDirtyRingReaper reaper;
};
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;
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;
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)
{
return gfn->flags == KVM_DIRTY_GFN_F_DIRTY;
}
static void dirty_gfn_set_collected(struct kvm_dirty_gfn *gfn)
{
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;
return count;
}
/* Must be with slots_lock held */
static uint64_t kvm_dirty_ring_reap_locked(KVMState *s)
{
int ret;
CPUState *cpu;
uint64_t total = 0;
int64_t stamp;
stamp = get_clock();
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)
{
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);
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);
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 = {
.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 defined(HOST_WORDS_BIGENDIAN) != defined(TARGET_WORDS_BIGENDIAN)
/* The kernel expects ioeventfd values in HOST_WORDS_BIGENDIAN
* 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 writeable = !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 (writeable || !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);
} 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);
trace_kvm_dirty_ring_reaper("wakeup");
r->reaper_state = KVM_DIRTY_RING_REAPER_REAPING;
qemu_mutex_lock_iothread();
kvm_dirty_ring_reap(s);
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)
{
int i;
kml->slots = g_malloc0(s->nr_slots * sizeof(KVMSlot));
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;
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 = {
.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_malloc0(sizeof(KVMMSIRoute));
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(KVMState *s, int vector, PCIDevice *dev)
{
struct kvm_irq_routing_entry kroute = {};
int virq;
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);
kvm_irqchip_commit_routes(s);
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(KVMState *s, 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) {
perror("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);
}
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");
}
#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 mininum 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);
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);
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;
}
}
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();
kvm_dirty_ring_reap(kvm_state);
qemu_mutex_unlock_iothread();
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;
}
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;
}
int kvm_insert_breakpoint(CPUState *cpu, target_ulong addr,
target_ulong len, int type)
{
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_malloc(sizeof(struct kvm_sw_breakpoint));
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, target_ulong addr,
target_ulong len, int type)
{
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);
}
}
#else /* !KVM_CAP_SET_GUEST_DEBUG */
int kvm_update_guest_debug(CPUState *cpu, unsigned long reinject_trap)
{
return -EINVAL;
}
int kvm_insert_breakpoint(CPUState *cpu, target_ulong addr,
target_ulong len, int type)
{
return -EINVAL;
}
int kvm_remove_breakpoint(CPUState *cpu, target_ulong addr,
target_ulong len, int type)
{
return -EINVAL;
}
void kvm_remove_all_breakpoints(CPUState *cpu)
{
}
#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;
}
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;
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)");
}
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);
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