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-rw-r--r--kernel/arch/x86/kvm/i8254.c781
1 files changed, 781 insertions, 0 deletions
diff --git a/kernel/arch/x86/kvm/i8254.c b/kernel/arch/x86/kvm/i8254.c
new file mode 100644
index 000000000..f90952f64
--- /dev/null
+++ b/kernel/arch/x86/kvm/i8254.c
@@ -0,0 +1,781 @@
+/*
+ * 8253/8254 interval timer emulation
+ *
+ * Copyright (c) 2003-2004 Fabrice Bellard
+ * Copyright (c) 2006 Intel Corporation
+ * Copyright (c) 2007 Keir Fraser, XenSource Inc
+ * Copyright (c) 2008 Intel Corporation
+ * Copyright 2009 Red Hat, Inc. and/or its affiliates.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * Authors:
+ * Sheng Yang <sheng.yang@intel.com>
+ * Based on QEMU and Xen.
+ */
+
+#define pr_fmt(fmt) "pit: " fmt
+
+#include <linux/kvm_host.h>
+#include <linux/slab.h>
+
+#include "irq.h"
+#include "i8254.h"
+#include "x86.h"
+
+#ifndef CONFIG_X86_64
+#define mod_64(x, y) ((x) - (y) * div64_u64(x, y))
+#else
+#define mod_64(x, y) ((x) % (y))
+#endif
+
+#define RW_STATE_LSB 1
+#define RW_STATE_MSB 2
+#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)
+{
+ 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));
+
+ switch (c->mode) {
+ default:
+ case 0:
+ case 4:
+ /* XXX: just disable/enable counting */
+ break;
+ case 1:
+ case 2:
+ case 3:
+ case 5:
+ /* Restart counting on rising edge. */
+ if (c->gate < val)
+ c->count_load_time = ktime_get();
+ break;
+ }
+
+ c->gate = val;
+}
+
+static int pit_get_gate(struct kvm *kvm, int channel)
+{
+ WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
+
+ return kvm->arch.vpit->pit_state.channels[channel].gate;
+}
+
+static s64 __kpit_elapsed(struct kvm *kvm)
+{
+ s64 elapsed;
+ ktime_t remaining;
+ struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state;
+
+ if (!ps->period)
+ return 0;
+
+ /*
+ * The Counter does not stop when it reaches zero. In
+ * Modes 0, 1, 4, and 5 the Counter ``wraps around'' to
+ * the highest count, either FFFF hex for binary counting
+ * or 9999 for BCD counting, and continues counting.
+ * Modes 2 and 3 are periodic; the Counter reloads
+ * itself with the initial count and continues counting
+ * from there.
+ */
+ remaining = hrtimer_get_remaining(&ps->timer);
+ elapsed = ps->period - ktime_to_ns(remaining);
+
+ return elapsed;
+}
+
+static s64 kpit_elapsed(struct kvm *kvm, struct kvm_kpit_channel_state *c,
+ int channel)
+{
+ if (channel == 0)
+ return __kpit_elapsed(kvm);
+
+ return ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
+}
+
+static int pit_get_count(struct kvm *kvm, int channel)
+{
+ struct kvm_kpit_channel_state *c =
+ &kvm->arch.vpit->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);
+
+ switch (c->mode) {
+ case 0:
+ case 1:
+ case 4:
+ case 5:
+ counter = (c->count - d) & 0xffff;
+ break;
+ case 3:
+ /* XXX: may be incorrect for odd counts */
+ counter = c->count - (mod_64((2 * d), c->count));
+ break;
+ default:
+ counter = c->count - mod_64(d, c->count);
+ break;
+ }
+ return counter;
+}
+
+static int pit_get_out(struct kvm *kvm, int channel)
+{
+ struct kvm_kpit_channel_state *c =
+ &kvm->arch.vpit->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);
+
+ switch (c->mode) {
+ default:
+ case 0:
+ out = (d >= c->count);
+ break;
+ case 1:
+ out = (d < c->count);
+ break;
+ case 2:
+ out = ((mod_64(d, c->count) == 0) && (d != 0));
+ break;
+ case 3:
+ out = (mod_64(d, c->count) < ((c->count + 1) >> 1));
+ break;
+ case 4:
+ case 5:
+ out = (d == c->count);
+ break;
+ }
+
+ return out;
+}
+
+static void pit_latch_count(struct kvm *kvm, 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));
+
+ if (!c->count_latched) {
+ c->latched_count = pit_get_count(kvm, channel);
+ c->count_latched = c->rw_mode;
+ }
+}
+
+static void pit_latch_status(struct kvm *kvm, 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));
+
+ if (!c->status_latched) {
+ /* TODO: Return NULL COUNT (bit 6). */
+ c->status = ((pit_get_out(kvm, channel) << 7) |
+ (c->rw_mode << 4) |
+ (c->mode << 1) |
+ c->bcd);
+ c->status_latched = 1;
+ }
+}
+
+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);
+}
+
+void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu)
+{
+ struct kvm_pit *pit = vcpu->kvm->arch.vpit;
+ struct hrtimer *timer;
+
+ if (!kvm_vcpu_is_bsp(vcpu) || !pit)
+ return;
+
+ timer = &pit->pit_state.timer;
+ mutex_lock(&pit->pit_state.lock);
+ if (hrtimer_cancel(timer))
+ hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
+ mutex_unlock(&pit->pit_state.lock);
+}
+
+static void destroy_pit_timer(struct kvm_pit *pit)
+{
+ hrtimer_cancel(&pit->pit_state.timer);
+ flush_kthread_work(&pit->expired);
+}
+
+static void pit_do_work(struct kthread_work *work)
+{
+ struct kvm_pit *pit = container_of(work, struct kvm_pit, expired);
+ struct kvm *kvm = pit->kvm;
+ 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.
+ */
+ 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);
+ }
+}
+
+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;
+
+ if (ps->reinject || !atomic_read(&ps->pending)) {
+ atomic_inc(&ps->pending);
+ queue_kthread_work(&pt->worker, &pt->expired);
+ }
+
+ if (ps->is_periodic) {
+ hrtimer_add_expires_ns(&ps->timer, ps->period);
+ return HRTIMER_RESTART;
+ } else
+ return HRTIMER_NORESTART;
+}
+
+static void create_pit_timer(struct kvm *kvm, u32 val, int is_period)
+{
+ struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state;
+ s64 interval;
+
+ if (!irqchip_in_kernel(kvm) || ps->flags & KVM_PIT_FLAGS_HPET_LEGACY)
+ return;
+
+ interval = muldiv64(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);
+ 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;
+
+ /*
+ * Do not allow the guest to program periodic timers with small
+ * interval, since the hrtimers are not throttled by the host
+ * scheduler.
+ */
+ if (ps->is_periodic) {
+ s64 min_period = min_timer_period_us * 1000LL;
+
+ if (ps->period < min_period) {
+ pr_info_ratelimited(
+ "kvm: requested %lld ns "
+ "i8254 timer period limited to %lld ns\n",
+ ps->period, min_period);
+ ps->period = min_period;
+ }
+ }
+
+ hrtimer_start(&ps->timer, ktime_add_ns(ktime_get(), interval),
+ HRTIMER_MODE_ABS);
+}
+
+static void pit_load_count(struct kvm *kvm, int channel, u32 val)
+{
+ struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state;
+
+ WARN_ON(!mutex_is_locked(&ps->lock));
+
+ pr_debug("load_count val is %d, channel is %d\n", val, channel);
+
+ /*
+ * The largest possible initial count is 0; this is equivalent
+ * to 216 for binary counting and 104 for BCD counting.
+ */
+ if (val == 0)
+ val = 0x10000;
+
+ ps->channels[channel].count = val;
+
+ if (channel != 0) {
+ ps->channels[channel].count_load_time = ktime_get();
+ return;
+ }
+
+ /* Two types of timer
+ * mode 1 is one shot, mode 2 is period, otherwise del timer */
+ switch (ps->channels[0].mode) {
+ case 0:
+ case 1:
+ /* FIXME: enhance mode 4 precision */
+ case 4:
+ create_pit_timer(kvm, val, 0);
+ break;
+ case 2:
+ case 3:
+ create_pit_timer(kvm, val, 1);
+ break;
+ default:
+ destroy_pit_timer(kvm->arch.vpit);
+ }
+}
+
+void kvm_pit_load_count(struct kvm *kvm, int channel, u32 val, int hpet_legacy_start)
+{
+ u8 saved_mode;
+ if (hpet_legacy_start) {
+ /* save existing mode for later reenablement */
+ 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;
+ } else {
+ pit_load_count(kvm, channel, val);
+ }
+}
+
+static inline struct kvm_pit *dev_to_pit(struct kvm_io_device *dev)
+{
+ return container_of(dev, struct kvm_pit, dev);
+}
+
+static inline struct kvm_pit *speaker_to_pit(struct kvm_io_device *dev)
+{
+ return container_of(dev, struct kvm_pit, speaker_dev);
+}
+
+static inline int pit_in_range(gpa_t addr)
+{
+ return ((addr >= KVM_PIT_BASE_ADDRESS) &&
+ (addr < KVM_PIT_BASE_ADDRESS + KVM_PIT_MEM_LENGTH));
+}
+
+static int pit_ioport_write(struct kvm_vcpu *vcpu,
+ struct kvm_io_device *this,
+ gpa_t addr, int len, const void *data)
+{
+ 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;
+ if (!pit_in_range(addr))
+ return -EOPNOTSUPP;
+
+ val &= 0xff;
+ addr &= KVM_PIT_CHANNEL_MASK;
+
+ mutex_lock(&pit_state->lock);
+
+ if (val != 0)
+ pr_debug("write addr is 0x%x, len is %d, val is 0x%x\n",
+ (unsigned int)addr, len, val);
+
+ if (addr == 3) {
+ channel = val >> 6;
+ if (channel == 3) {
+ /* Read-Back Command. */
+ for (channel = 0; channel < 3; channel++) {
+ s = &pit_state->channels[channel];
+ if (val & (2 << channel)) {
+ if (!(val & 0x20))
+ pit_latch_count(kvm, channel);
+ if (!(val & 0x10))
+ pit_latch_status(kvm, channel);
+ }
+ }
+ } else {
+ /* Select Counter <channel>. */
+ s = &pit_state->channels[channel];
+ access = (val >> 4) & KVM_PIT_CHANNEL_MASK;
+ if (access == 0) {
+ pit_latch_count(kvm, channel);
+ } else {
+ s->rw_mode = access;
+ s->read_state = access;
+ s->write_state = access;
+ s->mode = (val >> 1) & 7;
+ if (s->mode > 5)
+ s->mode -= 4;
+ s->bcd = val & 1;
+ }
+ }
+ } else {
+ /* Write Count. */
+ s = &pit_state->channels[addr];
+ switch (s->write_state) {
+ default:
+ case RW_STATE_LSB:
+ pit_load_count(kvm, addr, val);
+ break;
+ case RW_STATE_MSB:
+ pit_load_count(kvm, 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));
+ s->write_state = RW_STATE_WORD0;
+ break;
+ }
+ }
+
+ mutex_unlock(&pit_state->lock);
+ return 0;
+}
+
+static int pit_ioport_read(struct kvm_vcpu *vcpu,
+ struct kvm_io_device *this,
+ gpa_t addr, int len, void *data)
+{
+ 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))
+ return -EOPNOTSUPP;
+
+ addr &= KVM_PIT_CHANNEL_MASK;
+ if (addr == 3)
+ return 0;
+
+ s = &pit_state->channels[addr];
+
+ mutex_lock(&pit_state->lock);
+
+ if (s->status_latched) {
+ s->status_latched = 0;
+ ret = s->status;
+ } else if (s->count_latched) {
+ switch (s->count_latched) {
+ default:
+ case RW_STATE_LSB:
+ ret = s->latched_count & 0xff;
+ s->count_latched = 0;
+ break;
+ case RW_STATE_MSB:
+ ret = s->latched_count >> 8;
+ s->count_latched = 0;
+ break;
+ case RW_STATE_WORD0:
+ ret = s->latched_count & 0xff;
+ s->count_latched = RW_STATE_MSB;
+ break;
+ }
+ } else {
+ switch (s->read_state) {
+ default:
+ case RW_STATE_LSB:
+ count = pit_get_count(kvm, addr);
+ ret = count & 0xff;
+ break;
+ case RW_STATE_MSB:
+ count = pit_get_count(kvm, addr);
+ ret = (count >> 8) & 0xff;
+ break;
+ case RW_STATE_WORD0:
+ count = pit_get_count(kvm, addr);
+ ret = count & 0xff;
+ s->read_state = RW_STATE_WORD1;
+ break;
+ case RW_STATE_WORD1:
+ count = pit_get_count(kvm, addr);
+ ret = (count >> 8) & 0xff;
+ s->read_state = RW_STATE_WORD0;
+ break;
+ }
+ }
+
+ if (len > sizeof(ret))
+ len = sizeof(ret);
+ memcpy(data, (char *)&ret, len);
+
+ mutex_unlock(&pit_state->lock);
+ return 0;
+}
+
+static int speaker_ioport_write(struct kvm_vcpu *vcpu,
+ struct kvm_io_device *this,
+ gpa_t addr, int len, const void *data)
+{
+ 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);
+ mutex_unlock(&pit_state->lock);
+ return 0;
+}
+
+static int speaker_ioport_read(struct kvm_vcpu *vcpu,
+ struct kvm_io_device *this,
+ gpa_t addr, int len, void *data)
+{
+ 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)
+ return -EOPNOTSUPP;
+
+ /* Refresh clock toggles at about 15us. We approximate as 2^14ns. */
+ 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));
+ if (len > sizeof(ret))
+ len = sizeof(ret);
+ memcpy(data, (char *)&ret, len);
+ mutex_unlock(&pit_state->lock);
+ return 0;
+}
+
+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);
+ }
+ mutex_unlock(&pit->pit_state.lock);
+
+ atomic_set(&pit->pit_state.pending, 0);
+ pit->pit_state.irq_ack = 1;
+}
+
+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;
+ }
+}
+
+static const struct kvm_io_device_ops pit_dev_ops = {
+ .read = pit_ioport_read,
+ .write = pit_ioport_write,
+};
+
+static const struct kvm_io_device_ops speaker_dev_ops = {
+ .read = speaker_ioport_read,
+ .write = speaker_ioport_write,
+};
+
+/* Caller must hold slots_lock */
+struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
+{
+ struct kvm_pit *pit;
+ struct kvm_kpit_state *pit_state;
+ struct pid *pid;
+ pid_t pid_nr;
+ int ret;
+
+ pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL);
+ if (!pit)
+ return NULL;
+
+ pit->irq_source_id = kvm_request_irq_source_id(kvm);
+ if (pit->irq_source_id < 0) {
+ kfree(pit);
+ return NULL;
+ }
+
+ 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);
+ put_pid(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;
+ }
+ 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->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);
+
+ kvm_pit_reset(pit);
+
+ pit->mask_notifier.func = pit_mask_notifer;
+ kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
+
+ 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;
+
+ if (flags & KVM_PIT_SPEAKER_DUMMY) {
+ kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops);
+ ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS,
+ KVM_SPEAKER_BASE_ADDRESS, 4,
+ &pit->speaker_dev);
+ if (ret < 0)
+ goto fail_unregister;
+ }
+
+ return pit;
+
+fail_unregister:
+ 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);
+ kthread_stop(pit->worker_task);
+ 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);
+ }
+}