#define RW_STATE_WORD0 3
#define RW_STATE_WORD1 4
-/* Compute with 96 bit intermediate result: (a*b)/c */
-static u64 muldiv64(u64 a, u32 b, u32 c)
+static void pit_set_gate(struct kvm_pit *pit, int channel, u32 val)
{
- union {
- u64 ll;
- struct {
- u32 low, high;
- } l;
- } u, res;
- u64 rl, rh;
-
- u.ll = a;
- rl = (u64)u.l.low * (u64)b;
- rh = (u64)u.l.high * (u64)b;
- rh += (rl >> 32);
- res.l.high = div64_u64(rh, c);
- res.l.low = div64_u64(((mod_64(rh, c) << 32) + (rl & 0xffffffff)), c);
- return res.ll;
-}
-
-static void pit_set_gate(struct kvm *kvm, int channel, u32 val)
-{
- struct kvm_kpit_channel_state *c =
- &kvm->arch.vpit->pit_state.channels[channel];
-
- WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+ struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel];
switch (c->mode) {
default:
c->gate = val;
}
-static int pit_get_gate(struct kvm *kvm, int channel)
+static int pit_get_gate(struct kvm_pit *pit, int channel)
{
- WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
-
- return kvm->arch.vpit->pit_state.channels[channel].gate;
+ return pit->pit_state.channels[channel].gate;
}
-static s64 __kpit_elapsed(struct kvm *kvm)
+static s64 __kpit_elapsed(struct kvm_pit *pit)
{
s64 elapsed;
ktime_t remaining;
- struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state;
+ struct kvm_kpit_state *ps = &pit->pit_state;
if (!ps->period)
return 0;
return elapsed;
}
-static s64 kpit_elapsed(struct kvm *kvm, struct kvm_kpit_channel_state *c,
+static s64 kpit_elapsed(struct kvm_pit *pit, struct kvm_kpit_channel_state *c,
int channel)
{
if (channel == 0)
- return __kpit_elapsed(kvm);
+ return __kpit_elapsed(pit);
return ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
}
-static int pit_get_count(struct kvm *kvm, int channel)
+static int pit_get_count(struct kvm_pit *pit, int channel)
{
- struct kvm_kpit_channel_state *c =
- &kvm->arch.vpit->pit_state.channels[channel];
+ struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel];
s64 d, t;
int counter;
- WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
-
- t = kpit_elapsed(kvm, c, channel);
- d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC);
+ t = kpit_elapsed(pit, c, channel);
+ d = mul_u64_u32_div(t, KVM_PIT_FREQ, NSEC_PER_SEC);
switch (c->mode) {
case 0:
return counter;
}
-static int pit_get_out(struct kvm *kvm, int channel)
+static int pit_get_out(struct kvm_pit *pit, int channel)
{
- struct kvm_kpit_channel_state *c =
- &kvm->arch.vpit->pit_state.channels[channel];
+ struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel];
s64 d, t;
int out;
- WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
-
- t = kpit_elapsed(kvm, c, channel);
- d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC);
+ t = kpit_elapsed(pit, c, channel);
+ d = mul_u64_u32_div(t, KVM_PIT_FREQ, NSEC_PER_SEC);
switch (c->mode) {
default:
return out;
}
-static void pit_latch_count(struct kvm *kvm, int channel)
+static void pit_latch_count(struct kvm_pit *pit, int channel)
{
- struct kvm_kpit_channel_state *c =
- &kvm->arch.vpit->pit_state.channels[channel];
-
- WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+ struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel];
if (!c->count_latched) {
- c->latched_count = pit_get_count(kvm, channel);
+ c->latched_count = pit_get_count(pit, channel);
c->count_latched = c->rw_mode;
}
}
-static void pit_latch_status(struct kvm *kvm, int channel)
+static void pit_latch_status(struct kvm_pit *pit, int channel)
{
- struct kvm_kpit_channel_state *c =
- &kvm->arch.vpit->pit_state.channels[channel];
-
- WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+ struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel];
if (!c->status_latched) {
/* TODO: Return NULL COUNT (bit 6). */
- c->status = ((pit_get_out(kvm, channel) << 7) |
+ c->status = ((pit_get_out(pit, channel) << 7) |
(c->rw_mode << 4) |
(c->mode << 1) |
c->bcd);
}
}
+static inline struct kvm_pit *pit_state_to_pit(struct kvm_kpit_state *ps)
+{
+ return container_of(ps, struct kvm_pit, pit_state);
+}
+
static void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian)
{
struct kvm_kpit_state *ps = container_of(kian, struct kvm_kpit_state,
irq_ack_notifier);
- int value;
-
- spin_lock(&ps->inject_lock);
- value = atomic_dec_return(&ps->pending);
- if (value < 0)
- /* spurious acks can be generated if, for example, the
- * PIC is being reset. Handle it gracefully here
- */
- atomic_inc(&ps->pending);
- else if (value > 0)
- /* in this case, we had multiple outstanding pit interrupts
- * that we needed to inject. Reinject
- */
- queue_kthread_work(&ps->pit->worker, &ps->pit->expired);
- ps->irq_ack = 1;
- spin_unlock(&ps->inject_lock);
+ struct kvm_pit *pit = pit_state_to_pit(ps);
+
+ atomic_set(&ps->irq_ack, 1);
+ /* irq_ack should be set before pending is read. Order accesses with
+ * inc(pending) in pit_timer_fn and xchg(irq_ack, 0) in pit_do_work.
+ */
+ smp_mb();
+ if (atomic_dec_if_positive(&ps->pending) > 0)
+ queue_kthread_work(&pit->worker, &pit->expired);
}
void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu)
struct kvm_vcpu *vcpu;
int i;
struct kvm_kpit_state *ps = &pit->pit_state;
- int inject = 0;
- /* Try to inject pending interrupts when
- * last one has been acked.
+ if (atomic_read(&ps->reinject) && !atomic_xchg(&ps->irq_ack, 0))
+ return;
+
+ kvm_set_irq(kvm, pit->irq_source_id, 0, 1, false);
+ kvm_set_irq(kvm, pit->irq_source_id, 0, 0, false);
+
+ /*
+ * Provides NMI watchdog support via Virtual Wire mode.
+ * The route is: PIT -> LVT0 in NMI mode.
+ *
+ * Note: Our Virtual Wire implementation does not follow
+ * the MP specification. We propagate a PIT interrupt to all
+ * VCPUs and only when LVT0 is in NMI mode. The interrupt can
+ * also be simultaneously delivered through PIC and IOAPIC.
*/
- spin_lock(&ps->inject_lock);
- if (ps->irq_ack) {
- ps->irq_ack = 0;
- inject = 1;
- }
- spin_unlock(&ps->inject_lock);
- if (inject) {
- kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 1, false);
- kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 0, false);
-
- /*
- * Provides NMI watchdog support via Virtual Wire mode.
- * The route is: PIT -> PIC -> LVT0 in NMI mode.
- *
- * Note: Our Virtual Wire implementation is simplified, only
- * propagating PIT interrupts to all VCPUs when they have set
- * LVT0 to NMI delivery. Other PIC interrupts are just sent to
- * VCPU0, and only if its LVT0 is in EXTINT mode.
- */
- if (atomic_read(&kvm->arch.vapics_in_nmi_mode) > 0)
- kvm_for_each_vcpu(i, vcpu, kvm)
- kvm_apic_nmi_wd_deliver(vcpu);
- }
+ if (atomic_read(&kvm->arch.vapics_in_nmi_mode) > 0)
+ kvm_for_each_vcpu(i, vcpu, kvm)
+ kvm_apic_nmi_wd_deliver(vcpu);
}
static enum hrtimer_restart pit_timer_fn(struct hrtimer *data)
{
struct kvm_kpit_state *ps = container_of(data, struct kvm_kpit_state, timer);
- struct kvm_pit *pt = ps->kvm->arch.vpit;
+ struct kvm_pit *pt = pit_state_to_pit(ps);
- if (ps->reinject || !atomic_read(&ps->pending)) {
+ if (atomic_read(&ps->reinject))
atomic_inc(&ps->pending);
- queue_kthread_work(&pt->worker, &pt->expired);
- }
+
+ queue_kthread_work(&pt->worker, &pt->expired);
if (ps->is_periodic) {
hrtimer_add_expires_ns(&ps->timer, ps->period);
return HRTIMER_NORESTART;
}
-static void create_pit_timer(struct kvm *kvm, u32 val, int is_period)
+static inline void kvm_pit_reset_reinject(struct kvm_pit *pit)
{
- struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state;
+ atomic_set(&pit->pit_state.pending, 0);
+ atomic_set(&pit->pit_state.irq_ack, 1);
+}
+
+void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject)
+{
+ struct kvm_kpit_state *ps = &pit->pit_state;
+ struct kvm *kvm = pit->kvm;
+
+ if (atomic_read(&ps->reinject) == reinject)
+ return;
+
+ if (reinject) {
+ /* The initial state is preserved while ps->reinject == 0. */
+ kvm_pit_reset_reinject(pit);
+ kvm_register_irq_ack_notifier(kvm, &ps->irq_ack_notifier);
+ kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
+ } else {
+ kvm_unregister_irq_ack_notifier(kvm, &ps->irq_ack_notifier);
+ kvm_unregister_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
+ }
+
+ atomic_set(&ps->reinject, reinject);
+}
+
+static void create_pit_timer(struct kvm_pit *pit, u32 val, int is_period)
+{
+ struct kvm_kpit_state *ps = &pit->pit_state;
+ struct kvm *kvm = pit->kvm;
s64 interval;
if (!ioapic_in_kernel(kvm) ||
ps->flags & KVM_PIT_FLAGS_HPET_LEGACY)
return;
- interval = muldiv64(val, NSEC_PER_SEC, KVM_PIT_FREQ);
+ interval = mul_u64_u32_div(val, NSEC_PER_SEC, KVM_PIT_FREQ);
pr_debug("create pit timer, interval is %llu nsec\n", interval);
/* TODO The new value only affected after the retriggered */
hrtimer_cancel(&ps->timer);
- flush_kthread_work(&ps->pit->expired);
+ flush_kthread_work(&pit->expired);
ps->period = interval;
ps->is_periodic = is_period;
- ps->timer.function = pit_timer_fn;
- ps->kvm = ps->pit->kvm;
-
- atomic_set(&ps->pending, 0);
- ps->irq_ack = 1;
+ kvm_pit_reset_reinject(pit);
/*
* Do not allow the guest to program periodic timers with small
HRTIMER_MODE_ABS);
}
-static void pit_load_count(struct kvm *kvm, int channel, u32 val)
+static void pit_load_count(struct kvm_pit *pit, int channel, u32 val)
{
- struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state;
-
- WARN_ON(!mutex_is_locked(&ps->lock));
+ struct kvm_kpit_state *ps = &pit->pit_state;
pr_debug("load_count val is %d, channel is %d\n", val, channel);
case 1:
/* FIXME: enhance mode 4 precision */
case 4:
- create_pit_timer(kvm, val, 0);
+ create_pit_timer(pit, val, 0);
break;
case 2:
case 3:
- create_pit_timer(kvm, val, 1);
+ create_pit_timer(pit, val, 1);
break;
default:
- destroy_pit_timer(kvm->arch.vpit);
+ destroy_pit_timer(pit);
}
}
-void kvm_pit_load_count(struct kvm *kvm, int channel, u32 val, int hpet_legacy_start)
+void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val,
+ int hpet_legacy_start)
{
u8 saved_mode;
+
+ WARN_ON_ONCE(!mutex_is_locked(&pit->pit_state.lock));
+
if (hpet_legacy_start) {
/* save existing mode for later reenablement */
WARN_ON(channel != 0);
- saved_mode = kvm->arch.vpit->pit_state.channels[0].mode;
- kvm->arch.vpit->pit_state.channels[0].mode = 0xff; /* disable timer */
- pit_load_count(kvm, channel, val);
- kvm->arch.vpit->pit_state.channels[0].mode = saved_mode;
+ saved_mode = pit->pit_state.channels[0].mode;
+ pit->pit_state.channels[0].mode = 0xff; /* disable timer */
+ pit_load_count(pit, channel, val);
+ pit->pit_state.channels[0].mode = saved_mode;
} else {
- pit_load_count(kvm, channel, val);
+ pit_load_count(pit, channel, val);
}
}
{
struct kvm_pit *pit = dev_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
- struct kvm *kvm = pit->kvm;
int channel, access;
struct kvm_kpit_channel_state *s;
u32 val = *(u32 *) data;
s = &pit_state->channels[channel];
if (val & (2 << channel)) {
if (!(val & 0x20))
- pit_latch_count(kvm, channel);
+ pit_latch_count(pit, channel);
if (!(val & 0x10))
- pit_latch_status(kvm, channel);
+ pit_latch_status(pit, channel);
}
}
} else {
s = &pit_state->channels[channel];
access = (val >> 4) & KVM_PIT_CHANNEL_MASK;
if (access == 0) {
- pit_latch_count(kvm, channel);
+ pit_latch_count(pit, channel);
} else {
s->rw_mode = access;
s->read_state = access;
switch (s->write_state) {
default:
case RW_STATE_LSB:
- pit_load_count(kvm, addr, val);
+ pit_load_count(pit, addr, val);
break;
case RW_STATE_MSB:
- pit_load_count(kvm, addr, val << 8);
+ pit_load_count(pit, addr, val << 8);
break;
case RW_STATE_WORD0:
s->write_latch = val;
s->write_state = RW_STATE_WORD1;
break;
case RW_STATE_WORD1:
- pit_load_count(kvm, addr, s->write_latch | (val << 8));
+ pit_load_count(pit, addr, s->write_latch | (val << 8));
s->write_state = RW_STATE_WORD0;
break;
}
{
struct kvm_pit *pit = dev_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
- struct kvm *kvm = pit->kvm;
int ret, count;
struct kvm_kpit_channel_state *s;
if (!pit_in_range(addr))
switch (s->read_state) {
default:
case RW_STATE_LSB:
- count = pit_get_count(kvm, addr);
+ count = pit_get_count(pit, addr);
ret = count & 0xff;
break;
case RW_STATE_MSB:
- count = pit_get_count(kvm, addr);
+ count = pit_get_count(pit, addr);
ret = (count >> 8) & 0xff;
break;
case RW_STATE_WORD0:
- count = pit_get_count(kvm, addr);
+ count = pit_get_count(pit, addr);
ret = count & 0xff;
s->read_state = RW_STATE_WORD1;
break;
case RW_STATE_WORD1:
- count = pit_get_count(kvm, addr);
+ count = pit_get_count(pit, addr);
ret = (count >> 8) & 0xff;
s->read_state = RW_STATE_WORD0;
break;
{
struct kvm_pit *pit = speaker_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
- struct kvm *kvm = pit->kvm;
u32 val = *(u32 *) data;
if (addr != KVM_SPEAKER_BASE_ADDRESS)
return -EOPNOTSUPP;
mutex_lock(&pit_state->lock);
pit_state->speaker_data_on = (val >> 1) & 1;
- pit_set_gate(kvm, 2, val & 1);
+ pit_set_gate(pit, 2, val & 1);
mutex_unlock(&pit_state->lock);
return 0;
}
{
struct kvm_pit *pit = speaker_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
- struct kvm *kvm = pit->kvm;
unsigned int refresh_clock;
int ret;
if (addr != KVM_SPEAKER_BASE_ADDRESS)
refresh_clock = ((unsigned int)ktime_to_ns(ktime_get()) >> 14) & 1;
mutex_lock(&pit_state->lock);
- ret = ((pit_state->speaker_data_on << 1) | pit_get_gate(kvm, 2) |
- (pit_get_out(kvm, 2) << 5) | (refresh_clock << 4));
+ ret = ((pit_state->speaker_data_on << 1) | pit_get_gate(pit, 2) |
+ (pit_get_out(pit, 2) << 5) | (refresh_clock << 4));
if (len > sizeof(ret))
len = sizeof(ret);
memcpy(data, (char *)&ret, len);
return 0;
}
-void kvm_pit_reset(struct kvm_pit *pit)
+static void kvm_pit_reset(struct kvm_pit *pit)
{
int i;
struct kvm_kpit_channel_state *c;
- mutex_lock(&pit->pit_state.lock);
pit->pit_state.flags = 0;
for (i = 0; i < 3; i++) {
c = &pit->pit_state.channels[i];
c->mode = 0xff;
c->gate = (i != 2);
- pit_load_count(pit->kvm, i, 0);
+ pit_load_count(pit, i, 0);
}
- mutex_unlock(&pit->pit_state.lock);
- atomic_set(&pit->pit_state.pending, 0);
- pit->pit_state.irq_ack = 1;
+ kvm_pit_reset_reinject(pit);
}
static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask)
{
struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier);
- if (!mask) {
- atomic_set(&pit->pit_state.pending, 0);
- pit->pit_state.irq_ack = 1;
- }
+ if (!mask)
+ kvm_pit_reset_reinject(pit);
}
static const struct kvm_io_device_ops pit_dev_ops = {
return NULL;
pit->irq_source_id = kvm_request_irq_source_id(kvm);
- if (pit->irq_source_id < 0) {
- kfree(pit);
- return NULL;
- }
+ if (pit->irq_source_id < 0)
+ goto fail_request;
mutex_init(&pit->pit_state.lock);
- mutex_lock(&pit->pit_state.lock);
- spin_lock_init(&pit->pit_state.inject_lock);
pid = get_pid(task_tgid(current));
pid_nr = pid_vnr(pid);
init_kthread_worker(&pit->worker);
pit->worker_task = kthread_run(kthread_worker_fn, &pit->worker,
"kvm-pit/%d", pid_nr);
- if (IS_ERR(pit->worker_task)) {
- mutex_unlock(&pit->pit_state.lock);
- kvm_free_irq_source_id(kvm, pit->irq_source_id);
- kfree(pit);
- return NULL;
- }
+ if (IS_ERR(pit->worker_task))
+ goto fail_kthread;
+
init_kthread_work(&pit->expired, pit_do_work);
- kvm->arch.vpit = pit;
pit->kvm = kvm;
pit_state = &pit->pit_state;
- pit_state->pit = pit;
hrtimer_init(&pit_state->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+ pit_state->timer.function = pit_timer_fn;
+
pit_state->irq_ack_notifier.gsi = 0;
pit_state->irq_ack_notifier.irq_acked = kvm_pit_ack_irq;
- kvm_register_irq_ack_notifier(kvm, &pit_state->irq_ack_notifier);
- pit_state->reinject = true;
- mutex_unlock(&pit->pit_state.lock);
+ pit->mask_notifier.func = pit_mask_notifer;
kvm_pit_reset(pit);
- pit->mask_notifier.func = pit_mask_notifer;
- kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
+ kvm_pit_set_reinject(pit, true);
kvm_iodevice_init(&pit->dev, &pit_dev_ops);
ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, KVM_PIT_BASE_ADDRESS,
KVM_PIT_MEM_LENGTH, &pit->dev);
if (ret < 0)
- goto fail;
+ goto fail_register_pit;
if (flags & KVM_PIT_SPEAKER_DUMMY) {
kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops);
KVM_SPEAKER_BASE_ADDRESS, 4,
&pit->speaker_dev);
if (ret < 0)
- goto fail_unregister;
+ goto fail_register_speaker;
}
return pit;
-fail_unregister:
+fail_register_speaker:
kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev);
-
-fail:
- kvm_unregister_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
- kvm_unregister_irq_ack_notifier(kvm, &pit_state->irq_ack_notifier);
- kvm_free_irq_source_id(kvm, pit->irq_source_id);
+fail_register_pit:
+ kvm_pit_set_reinject(pit, false);
kthread_stop(pit->worker_task);
+fail_kthread:
+ kvm_free_irq_source_id(kvm, pit->irq_source_id);
+fail_request:
kfree(pit);
return NULL;
}
void kvm_free_pit(struct kvm *kvm)
{
- struct hrtimer *timer;
-
- if (kvm->arch.vpit) {
- kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &kvm->arch.vpit->dev);
- kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS,
- &kvm->arch.vpit->speaker_dev);
- kvm_unregister_irq_mask_notifier(kvm, 0,
- &kvm->arch.vpit->mask_notifier);
- kvm_unregister_irq_ack_notifier(kvm,
- &kvm->arch.vpit->pit_state.irq_ack_notifier);
- mutex_lock(&kvm->arch.vpit->pit_state.lock);
- timer = &kvm->arch.vpit->pit_state.timer;
- hrtimer_cancel(timer);
- flush_kthread_work(&kvm->arch.vpit->expired);
- kthread_stop(kvm->arch.vpit->worker_task);
- kvm_free_irq_source_id(kvm, kvm->arch.vpit->irq_source_id);
- mutex_unlock(&kvm->arch.vpit->pit_state.lock);
- kfree(kvm->arch.vpit);
+ struct kvm_pit *pit = kvm->arch.vpit;
+
+ if (pit) {
+ kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev);
+ kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->speaker_dev);
+ kvm_pit_set_reinject(pit, false);
+ hrtimer_cancel(&pit->pit_state.timer);
+ flush_kthread_work(&pit->expired);
+ kthread_stop(pit->worker_task);
+ kvm_free_irq_source_id(kvm, pit->irq_source_id);
+ kfree(pit);
}
}
projects / cascardo / linux.git / blobdiff