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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/arm64/kvm/arch_timer.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm64/kvm/arch_timer.c')
-rw-r--r--arch/arm64/kvm/arch_timer.c1684
1 files changed, 1684 insertions, 0 deletions
diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c
new file mode 100644
index 0000000000..a1e24228aa
--- /dev/null
+++ b/arch/arm64/kvm/arch_timer.c
@@ -0,0 +1,1684 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ */
+
+#include <linux/cpu.h>
+#include <linux/kvm.h>
+#include <linux/kvm_host.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/uaccess.h>
+
+#include <clocksource/arm_arch_timer.h>
+#include <asm/arch_timer.h>
+#include <asm/kvm_emulate.h>
+#include <asm/kvm_hyp.h>
+#include <asm/kvm_nested.h>
+
+#include <kvm/arm_vgic.h>
+#include <kvm/arm_arch_timer.h>
+
+#include "trace.h"
+
+static struct timecounter *timecounter;
+static unsigned int host_vtimer_irq;
+static unsigned int host_ptimer_irq;
+static u32 host_vtimer_irq_flags;
+static u32 host_ptimer_irq_flags;
+
+static DEFINE_STATIC_KEY_FALSE(has_gic_active_state);
+
+static const u8 default_ppi[] = {
+ [TIMER_PTIMER] = 30,
+ [TIMER_VTIMER] = 27,
+ [TIMER_HPTIMER] = 26,
+ [TIMER_HVTIMER] = 28,
+};
+
+static bool kvm_timer_irq_can_fire(struct arch_timer_context *timer_ctx);
+static void kvm_timer_update_irq(struct kvm_vcpu *vcpu, bool new_level,
+ struct arch_timer_context *timer_ctx);
+static bool kvm_timer_should_fire(struct arch_timer_context *timer_ctx);
+static void kvm_arm_timer_write(struct kvm_vcpu *vcpu,
+ struct arch_timer_context *timer,
+ enum kvm_arch_timer_regs treg,
+ u64 val);
+static u64 kvm_arm_timer_read(struct kvm_vcpu *vcpu,
+ struct arch_timer_context *timer,
+ enum kvm_arch_timer_regs treg);
+static bool kvm_arch_timer_get_input_level(int vintid);
+
+static struct irq_ops arch_timer_irq_ops = {
+ .get_input_level = kvm_arch_timer_get_input_level,
+};
+
+static int nr_timers(struct kvm_vcpu *vcpu)
+{
+ if (!vcpu_has_nv(vcpu))
+ return NR_KVM_EL0_TIMERS;
+
+ return NR_KVM_TIMERS;
+}
+
+u32 timer_get_ctl(struct arch_timer_context *ctxt)
+{
+ struct kvm_vcpu *vcpu = ctxt->vcpu;
+
+ switch(arch_timer_ctx_index(ctxt)) {
+ case TIMER_VTIMER:
+ return __vcpu_sys_reg(vcpu, CNTV_CTL_EL0);
+ case TIMER_PTIMER:
+ return __vcpu_sys_reg(vcpu, CNTP_CTL_EL0);
+ case TIMER_HVTIMER:
+ return __vcpu_sys_reg(vcpu, CNTHV_CTL_EL2);
+ case TIMER_HPTIMER:
+ return __vcpu_sys_reg(vcpu, CNTHP_CTL_EL2);
+ default:
+ WARN_ON(1);
+ return 0;
+ }
+}
+
+u64 timer_get_cval(struct arch_timer_context *ctxt)
+{
+ struct kvm_vcpu *vcpu = ctxt->vcpu;
+
+ switch(arch_timer_ctx_index(ctxt)) {
+ case TIMER_VTIMER:
+ return __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0);
+ case TIMER_PTIMER:
+ return __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
+ case TIMER_HVTIMER:
+ return __vcpu_sys_reg(vcpu, CNTHV_CVAL_EL2);
+ case TIMER_HPTIMER:
+ return __vcpu_sys_reg(vcpu, CNTHP_CVAL_EL2);
+ default:
+ WARN_ON(1);
+ return 0;
+ }
+}
+
+static u64 timer_get_offset(struct arch_timer_context *ctxt)
+{
+ u64 offset = 0;
+
+ if (!ctxt)
+ return 0;
+
+ if (ctxt->offset.vm_offset)
+ offset += *ctxt->offset.vm_offset;
+ if (ctxt->offset.vcpu_offset)
+ offset += *ctxt->offset.vcpu_offset;
+
+ return offset;
+}
+
+static void timer_set_ctl(struct arch_timer_context *ctxt, u32 ctl)
+{
+ struct kvm_vcpu *vcpu = ctxt->vcpu;
+
+ switch(arch_timer_ctx_index(ctxt)) {
+ case TIMER_VTIMER:
+ __vcpu_sys_reg(vcpu, CNTV_CTL_EL0) = ctl;
+ break;
+ case TIMER_PTIMER:
+ __vcpu_sys_reg(vcpu, CNTP_CTL_EL0) = ctl;
+ break;
+ case TIMER_HVTIMER:
+ __vcpu_sys_reg(vcpu, CNTHV_CTL_EL2) = ctl;
+ break;
+ case TIMER_HPTIMER:
+ __vcpu_sys_reg(vcpu, CNTHP_CTL_EL2) = ctl;
+ break;
+ default:
+ WARN_ON(1);
+ }
+}
+
+static void timer_set_cval(struct arch_timer_context *ctxt, u64 cval)
+{
+ struct kvm_vcpu *vcpu = ctxt->vcpu;
+
+ switch(arch_timer_ctx_index(ctxt)) {
+ case TIMER_VTIMER:
+ __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0) = cval;
+ break;
+ case TIMER_PTIMER:
+ __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0) = cval;
+ break;
+ case TIMER_HVTIMER:
+ __vcpu_sys_reg(vcpu, CNTHV_CVAL_EL2) = cval;
+ break;
+ case TIMER_HPTIMER:
+ __vcpu_sys_reg(vcpu, CNTHP_CVAL_EL2) = cval;
+ break;
+ default:
+ WARN_ON(1);
+ }
+}
+
+static void timer_set_offset(struct arch_timer_context *ctxt, u64 offset)
+{
+ if (!ctxt->offset.vm_offset) {
+ WARN(offset, "timer %ld\n", arch_timer_ctx_index(ctxt));
+ return;
+ }
+
+ WRITE_ONCE(*ctxt->offset.vm_offset, offset);
+}
+
+u64 kvm_phys_timer_read(void)
+{
+ return timecounter->cc->read(timecounter->cc);
+}
+
+void get_timer_map(struct kvm_vcpu *vcpu, struct timer_map *map)
+{
+ if (vcpu_has_nv(vcpu)) {
+ if (is_hyp_ctxt(vcpu)) {
+ map->direct_vtimer = vcpu_hvtimer(vcpu);
+ map->direct_ptimer = vcpu_hptimer(vcpu);
+ map->emul_vtimer = vcpu_vtimer(vcpu);
+ map->emul_ptimer = vcpu_ptimer(vcpu);
+ } else {
+ map->direct_vtimer = vcpu_vtimer(vcpu);
+ map->direct_ptimer = vcpu_ptimer(vcpu);
+ map->emul_vtimer = vcpu_hvtimer(vcpu);
+ map->emul_ptimer = vcpu_hptimer(vcpu);
+ }
+ } else if (has_vhe()) {
+ map->direct_vtimer = vcpu_vtimer(vcpu);
+ map->direct_ptimer = vcpu_ptimer(vcpu);
+ map->emul_vtimer = NULL;
+ map->emul_ptimer = NULL;
+ } else {
+ map->direct_vtimer = vcpu_vtimer(vcpu);
+ map->direct_ptimer = NULL;
+ map->emul_vtimer = NULL;
+ map->emul_ptimer = vcpu_ptimer(vcpu);
+ }
+
+ trace_kvm_get_timer_map(vcpu->vcpu_id, map);
+}
+
+static inline bool userspace_irqchip(struct kvm *kvm)
+{
+ return static_branch_unlikely(&userspace_irqchip_in_use) &&
+ unlikely(!irqchip_in_kernel(kvm));
+}
+
+static void soft_timer_start(struct hrtimer *hrt, u64 ns)
+{
+ hrtimer_start(hrt, ktime_add_ns(ktime_get(), ns),
+ HRTIMER_MODE_ABS_HARD);
+}
+
+static void soft_timer_cancel(struct hrtimer *hrt)
+{
+ hrtimer_cancel(hrt);
+}
+
+static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id)
+{
+ struct kvm_vcpu *vcpu = *(struct kvm_vcpu **)dev_id;
+ struct arch_timer_context *ctx;
+ struct timer_map map;
+
+ /*
+ * We may see a timer interrupt after vcpu_put() has been called which
+ * sets the CPU's vcpu pointer to NULL, because even though the timer
+ * has been disabled in timer_save_state(), the hardware interrupt
+ * signal may not have been retired from the interrupt controller yet.
+ */
+ if (!vcpu)
+ return IRQ_HANDLED;
+
+ get_timer_map(vcpu, &map);
+
+ if (irq == host_vtimer_irq)
+ ctx = map.direct_vtimer;
+ else
+ ctx = map.direct_ptimer;
+
+ if (kvm_timer_should_fire(ctx))
+ kvm_timer_update_irq(vcpu, true, ctx);
+
+ if (userspace_irqchip(vcpu->kvm) &&
+ !static_branch_unlikely(&has_gic_active_state))
+ disable_percpu_irq(host_vtimer_irq);
+
+ return IRQ_HANDLED;
+}
+
+static u64 kvm_counter_compute_delta(struct arch_timer_context *timer_ctx,
+ u64 val)
+{
+ u64 now = kvm_phys_timer_read() - timer_get_offset(timer_ctx);
+
+ if (now < val) {
+ u64 ns;
+
+ ns = cyclecounter_cyc2ns(timecounter->cc,
+ val - now,
+ timecounter->mask,
+ &timer_ctx->ns_frac);
+ return ns;
+ }
+
+ return 0;
+}
+
+static u64 kvm_timer_compute_delta(struct arch_timer_context *timer_ctx)
+{
+ return kvm_counter_compute_delta(timer_ctx, timer_get_cval(timer_ctx));
+}
+
+static bool kvm_timer_irq_can_fire(struct arch_timer_context *timer_ctx)
+{
+ WARN_ON(timer_ctx && timer_ctx->loaded);
+ return timer_ctx &&
+ ((timer_get_ctl(timer_ctx) &
+ (ARCH_TIMER_CTRL_IT_MASK | ARCH_TIMER_CTRL_ENABLE)) == ARCH_TIMER_CTRL_ENABLE);
+}
+
+static bool vcpu_has_wfit_active(struct kvm_vcpu *vcpu)
+{
+ return (cpus_have_final_cap(ARM64_HAS_WFXT) &&
+ vcpu_get_flag(vcpu, IN_WFIT));
+}
+
+static u64 wfit_delay_ns(struct kvm_vcpu *vcpu)
+{
+ u64 val = vcpu_get_reg(vcpu, kvm_vcpu_sys_get_rt(vcpu));
+ struct arch_timer_context *ctx;
+
+ ctx = (vcpu_has_nv(vcpu) && is_hyp_ctxt(vcpu)) ? vcpu_hvtimer(vcpu)
+ : vcpu_vtimer(vcpu);
+
+ return kvm_counter_compute_delta(ctx, val);
+}
+
+/*
+ * Returns the earliest expiration time in ns among guest timers.
+ * Note that it will return 0 if none of timers can fire.
+ */
+static u64 kvm_timer_earliest_exp(struct kvm_vcpu *vcpu)
+{
+ u64 min_delta = ULLONG_MAX;
+ int i;
+
+ for (i = 0; i < nr_timers(vcpu); i++) {
+ struct arch_timer_context *ctx = &vcpu->arch.timer_cpu.timers[i];
+
+ WARN(ctx->loaded, "timer %d loaded\n", i);
+ if (kvm_timer_irq_can_fire(ctx))
+ min_delta = min(min_delta, kvm_timer_compute_delta(ctx));
+ }
+
+ if (vcpu_has_wfit_active(vcpu))
+ min_delta = min(min_delta, wfit_delay_ns(vcpu));
+
+ /* If none of timers can fire, then return 0 */
+ if (min_delta == ULLONG_MAX)
+ return 0;
+
+ return min_delta;
+}
+
+static enum hrtimer_restart kvm_bg_timer_expire(struct hrtimer *hrt)
+{
+ struct arch_timer_cpu *timer;
+ struct kvm_vcpu *vcpu;
+ u64 ns;
+
+ timer = container_of(hrt, struct arch_timer_cpu, bg_timer);
+ vcpu = container_of(timer, struct kvm_vcpu, arch.timer_cpu);
+
+ /*
+ * Check that the timer has really expired from the guest's
+ * PoV (NTP on the host may have forced it to expire
+ * early). If we should have slept longer, restart it.
+ */
+ ns = kvm_timer_earliest_exp(vcpu);
+ if (unlikely(ns)) {
+ hrtimer_forward_now(hrt, ns_to_ktime(ns));
+ return HRTIMER_RESTART;
+ }
+
+ kvm_vcpu_wake_up(vcpu);
+ return HRTIMER_NORESTART;
+}
+
+static enum hrtimer_restart kvm_hrtimer_expire(struct hrtimer *hrt)
+{
+ struct arch_timer_context *ctx;
+ struct kvm_vcpu *vcpu;
+ u64 ns;
+
+ ctx = container_of(hrt, struct arch_timer_context, hrtimer);
+ vcpu = ctx->vcpu;
+
+ trace_kvm_timer_hrtimer_expire(ctx);
+
+ /*
+ * Check that the timer has really expired from the guest's
+ * PoV (NTP on the host may have forced it to expire
+ * early). If not ready, schedule for a later time.
+ */
+ ns = kvm_timer_compute_delta(ctx);
+ if (unlikely(ns)) {
+ hrtimer_forward_now(hrt, ns_to_ktime(ns));
+ return HRTIMER_RESTART;
+ }
+
+ kvm_timer_update_irq(vcpu, true, ctx);
+ return HRTIMER_NORESTART;
+}
+
+static bool kvm_timer_should_fire(struct arch_timer_context *timer_ctx)
+{
+ enum kvm_arch_timers index;
+ u64 cval, now;
+
+ if (!timer_ctx)
+ return false;
+
+ index = arch_timer_ctx_index(timer_ctx);
+
+ if (timer_ctx->loaded) {
+ u32 cnt_ctl = 0;
+
+ switch (index) {
+ case TIMER_VTIMER:
+ case TIMER_HVTIMER:
+ cnt_ctl = read_sysreg_el0(SYS_CNTV_CTL);
+ break;
+ case TIMER_PTIMER:
+ case TIMER_HPTIMER:
+ cnt_ctl = read_sysreg_el0(SYS_CNTP_CTL);
+ break;
+ case NR_KVM_TIMERS:
+ /* GCC is braindead */
+ cnt_ctl = 0;
+ break;
+ }
+
+ return (cnt_ctl & ARCH_TIMER_CTRL_ENABLE) &&
+ (cnt_ctl & ARCH_TIMER_CTRL_IT_STAT) &&
+ !(cnt_ctl & ARCH_TIMER_CTRL_IT_MASK);
+ }
+
+ if (!kvm_timer_irq_can_fire(timer_ctx))
+ return false;
+
+ cval = timer_get_cval(timer_ctx);
+ now = kvm_phys_timer_read() - timer_get_offset(timer_ctx);
+
+ return cval <= now;
+}
+
+int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
+{
+ return vcpu_has_wfit_active(vcpu) && wfit_delay_ns(vcpu) == 0;
+}
+
+/*
+ * Reflect the timer output level into the kvm_run structure
+ */
+void kvm_timer_update_run(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
+ struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
+ struct kvm_sync_regs *regs = &vcpu->run->s.regs;
+
+ /* Populate the device bitmap with the timer states */
+ regs->device_irq_level &= ~(KVM_ARM_DEV_EL1_VTIMER |
+ KVM_ARM_DEV_EL1_PTIMER);
+ if (kvm_timer_should_fire(vtimer))
+ regs->device_irq_level |= KVM_ARM_DEV_EL1_VTIMER;
+ if (kvm_timer_should_fire(ptimer))
+ regs->device_irq_level |= KVM_ARM_DEV_EL1_PTIMER;
+}
+
+static void kvm_timer_update_irq(struct kvm_vcpu *vcpu, bool new_level,
+ struct arch_timer_context *timer_ctx)
+{
+ int ret;
+
+ timer_ctx->irq.level = new_level;
+ trace_kvm_timer_update_irq(vcpu->vcpu_id, timer_irq(timer_ctx),
+ timer_ctx->irq.level);
+
+ if (!userspace_irqchip(vcpu->kvm)) {
+ ret = kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id,
+ timer_irq(timer_ctx),
+ timer_ctx->irq.level,
+ timer_ctx);
+ WARN_ON(ret);
+ }
+}
+
+/* Only called for a fully emulated timer */
+static void timer_emulate(struct arch_timer_context *ctx)
+{
+ bool should_fire = kvm_timer_should_fire(ctx);
+
+ trace_kvm_timer_emulate(ctx, should_fire);
+
+ if (should_fire != ctx->irq.level) {
+ kvm_timer_update_irq(ctx->vcpu, should_fire, ctx);
+ return;
+ }
+
+ /*
+ * If the timer can fire now, we don't need to have a soft timer
+ * scheduled for the future. If the timer cannot fire at all,
+ * then we also don't need a soft timer.
+ */
+ if (should_fire || !kvm_timer_irq_can_fire(ctx))
+ return;
+
+ soft_timer_start(&ctx->hrtimer, kvm_timer_compute_delta(ctx));
+}
+
+static void set_cntvoff(u64 cntvoff)
+{
+ kvm_call_hyp(__kvm_timer_set_cntvoff, cntvoff);
+}
+
+static void set_cntpoff(u64 cntpoff)
+{
+ if (has_cntpoff())
+ write_sysreg_s(cntpoff, SYS_CNTPOFF_EL2);
+}
+
+static void timer_save_state(struct arch_timer_context *ctx)
+{
+ struct arch_timer_cpu *timer = vcpu_timer(ctx->vcpu);
+ enum kvm_arch_timers index = arch_timer_ctx_index(ctx);
+ unsigned long flags;
+
+ if (!timer->enabled)
+ return;
+
+ local_irq_save(flags);
+
+ if (!ctx->loaded)
+ goto out;
+
+ switch (index) {
+ u64 cval;
+
+ case TIMER_VTIMER:
+ case TIMER_HVTIMER:
+ timer_set_ctl(ctx, read_sysreg_el0(SYS_CNTV_CTL));
+ timer_set_cval(ctx, read_sysreg_el0(SYS_CNTV_CVAL));
+
+ /* Disable the timer */
+ write_sysreg_el0(0, SYS_CNTV_CTL);
+ isb();
+
+ /*
+ * The kernel may decide to run userspace after
+ * calling vcpu_put, so we reset cntvoff to 0 to
+ * ensure a consistent read between user accesses to
+ * the virtual counter and kernel access to the
+ * physical counter of non-VHE case.
+ *
+ * For VHE, the virtual counter uses a fixed virtual
+ * offset of zero, so no need to zero CNTVOFF_EL2
+ * register, but this is actually useful when switching
+ * between EL1/vEL2 with NV.
+ *
+ * Do it unconditionally, as this is either unavoidable
+ * or dirt cheap.
+ */
+ set_cntvoff(0);
+ break;
+ case TIMER_PTIMER:
+ case TIMER_HPTIMER:
+ timer_set_ctl(ctx, read_sysreg_el0(SYS_CNTP_CTL));
+ cval = read_sysreg_el0(SYS_CNTP_CVAL);
+
+ cval -= timer_get_offset(ctx);
+
+ timer_set_cval(ctx, cval);
+
+ /* Disable the timer */
+ write_sysreg_el0(0, SYS_CNTP_CTL);
+ isb();
+
+ set_cntpoff(0);
+ break;
+ case NR_KVM_TIMERS:
+ BUG();
+ }
+
+ trace_kvm_timer_save_state(ctx);
+
+ ctx->loaded = false;
+out:
+ local_irq_restore(flags);
+}
+
+/*
+ * Schedule the background timer before calling kvm_vcpu_halt, so that this
+ * thread is removed from its waitqueue and made runnable when there's a timer
+ * interrupt to handle.
+ */
+static void kvm_timer_blocking(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_cpu *timer = vcpu_timer(vcpu);
+ struct timer_map map;
+
+ get_timer_map(vcpu, &map);
+
+ /*
+ * If no timers are capable of raising interrupts (disabled or
+ * masked), then there's no more work for us to do.
+ */
+ if (!kvm_timer_irq_can_fire(map.direct_vtimer) &&
+ !kvm_timer_irq_can_fire(map.direct_ptimer) &&
+ !kvm_timer_irq_can_fire(map.emul_vtimer) &&
+ !kvm_timer_irq_can_fire(map.emul_ptimer) &&
+ !vcpu_has_wfit_active(vcpu))
+ return;
+
+ /*
+ * At least one guest time will expire. Schedule a background timer.
+ * Set the earliest expiration time among the guest timers.
+ */
+ soft_timer_start(&timer->bg_timer, kvm_timer_earliest_exp(vcpu));
+}
+
+static void kvm_timer_unblocking(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_cpu *timer = vcpu_timer(vcpu);
+
+ soft_timer_cancel(&timer->bg_timer);
+}
+
+static void timer_restore_state(struct arch_timer_context *ctx)
+{
+ struct arch_timer_cpu *timer = vcpu_timer(ctx->vcpu);
+ enum kvm_arch_timers index = arch_timer_ctx_index(ctx);
+ unsigned long flags;
+
+ if (!timer->enabled)
+ return;
+
+ local_irq_save(flags);
+
+ if (ctx->loaded)
+ goto out;
+
+ switch (index) {
+ u64 cval, offset;
+
+ case TIMER_VTIMER:
+ case TIMER_HVTIMER:
+ set_cntvoff(timer_get_offset(ctx));
+ write_sysreg_el0(timer_get_cval(ctx), SYS_CNTV_CVAL);
+ isb();
+ write_sysreg_el0(timer_get_ctl(ctx), SYS_CNTV_CTL);
+ break;
+ case TIMER_PTIMER:
+ case TIMER_HPTIMER:
+ cval = timer_get_cval(ctx);
+ offset = timer_get_offset(ctx);
+ set_cntpoff(offset);
+ cval += offset;
+ write_sysreg_el0(cval, SYS_CNTP_CVAL);
+ isb();
+ write_sysreg_el0(timer_get_ctl(ctx), SYS_CNTP_CTL);
+ break;
+ case NR_KVM_TIMERS:
+ BUG();
+ }
+
+ trace_kvm_timer_restore_state(ctx);
+
+ ctx->loaded = true;
+out:
+ local_irq_restore(flags);
+}
+
+static inline void set_timer_irq_phys_active(struct arch_timer_context *ctx, bool active)
+{
+ int r;
+ r = irq_set_irqchip_state(ctx->host_timer_irq, IRQCHIP_STATE_ACTIVE, active);
+ WARN_ON(r);
+}
+
+static void kvm_timer_vcpu_load_gic(struct arch_timer_context *ctx)
+{
+ struct kvm_vcpu *vcpu = ctx->vcpu;
+ bool phys_active = false;
+
+ /*
+ * Update the timer output so that it is likely to match the
+ * state we're about to restore. If the timer expires between
+ * this point and the register restoration, we'll take the
+ * interrupt anyway.
+ */
+ kvm_timer_update_irq(ctx->vcpu, kvm_timer_should_fire(ctx), ctx);
+
+ if (irqchip_in_kernel(vcpu->kvm))
+ phys_active = kvm_vgic_map_is_active(vcpu, timer_irq(ctx));
+
+ phys_active |= ctx->irq.level;
+
+ set_timer_irq_phys_active(ctx, phys_active);
+}
+
+static void kvm_timer_vcpu_load_nogic(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
+
+ /*
+ * Update the timer output so that it is likely to match the
+ * state we're about to restore. If the timer expires between
+ * this point and the register restoration, we'll take the
+ * interrupt anyway.
+ */
+ kvm_timer_update_irq(vcpu, kvm_timer_should_fire(vtimer), vtimer);
+
+ /*
+ * When using a userspace irqchip with the architected timers and a
+ * host interrupt controller that doesn't support an active state, we
+ * must still prevent continuously exiting from the guest, and
+ * therefore mask the physical interrupt by disabling it on the host
+ * interrupt controller when the virtual level is high, such that the
+ * guest can make forward progress. Once we detect the output level
+ * being de-asserted, we unmask the interrupt again so that we exit
+ * from the guest when the timer fires.
+ */
+ if (vtimer->irq.level)
+ disable_percpu_irq(host_vtimer_irq);
+ else
+ enable_percpu_irq(host_vtimer_irq, host_vtimer_irq_flags);
+}
+
+/* If _pred is true, set bit in _set, otherwise set it in _clr */
+#define assign_clear_set_bit(_pred, _bit, _clr, _set) \
+ do { \
+ if (_pred) \
+ (_set) |= (_bit); \
+ else \
+ (_clr) |= (_bit); \
+ } while (0)
+
+static void kvm_timer_vcpu_load_nested_switch(struct kvm_vcpu *vcpu,
+ struct timer_map *map)
+{
+ int hw, ret;
+
+ if (!irqchip_in_kernel(vcpu->kvm))
+ return;
+
+ /*
+ * We only ever unmap the vtimer irq on a VHE system that runs nested
+ * virtualization, in which case we have both a valid emul_vtimer,
+ * emul_ptimer, direct_vtimer, and direct_ptimer.
+ *
+ * Since this is called from kvm_timer_vcpu_load(), a change between
+ * vEL2 and vEL1/0 will have just happened, and the timer_map will
+ * represent this, and therefore we switch the emul/direct mappings
+ * below.
+ */
+ hw = kvm_vgic_get_map(vcpu, timer_irq(map->direct_vtimer));
+ if (hw < 0) {
+ kvm_vgic_unmap_phys_irq(vcpu, timer_irq(map->emul_vtimer));
+ kvm_vgic_unmap_phys_irq(vcpu, timer_irq(map->emul_ptimer));
+
+ ret = kvm_vgic_map_phys_irq(vcpu,
+ map->direct_vtimer->host_timer_irq,
+ timer_irq(map->direct_vtimer),
+ &arch_timer_irq_ops);
+ WARN_ON_ONCE(ret);
+ ret = kvm_vgic_map_phys_irq(vcpu,
+ map->direct_ptimer->host_timer_irq,
+ timer_irq(map->direct_ptimer),
+ &arch_timer_irq_ops);
+ WARN_ON_ONCE(ret);
+
+ /*
+ * The virtual offset behaviour is "interresting", as it
+ * always applies when HCR_EL2.E2H==0, but only when
+ * accessed from EL1 when HCR_EL2.E2H==1. So make sure we
+ * track E2H when putting the HV timer in "direct" mode.
+ */
+ if (map->direct_vtimer == vcpu_hvtimer(vcpu)) {
+ struct arch_timer_offset *offs = &map->direct_vtimer->offset;
+
+ if (vcpu_el2_e2h_is_set(vcpu))
+ offs->vcpu_offset = NULL;
+ else
+ offs->vcpu_offset = &__vcpu_sys_reg(vcpu, CNTVOFF_EL2);
+ }
+ }
+}
+
+static void timer_set_traps(struct kvm_vcpu *vcpu, struct timer_map *map)
+{
+ bool tpt, tpc;
+ u64 clr, set;
+
+ /*
+ * No trapping gets configured here with nVHE. See
+ * __timer_enable_traps(), which is where the stuff happens.
+ */
+ if (!has_vhe())
+ return;
+
+ /*
+ * Our default policy is not to trap anything. As we progress
+ * within this function, reality kicks in and we start adding
+ * traps based on emulation requirements.
+ */
+ tpt = tpc = false;
+
+ /*
+ * We have two possibility to deal with a physical offset:
+ *
+ * - Either we have CNTPOFF (yay!) or the offset is 0:
+ * we let the guest freely access the HW
+ *
+ * - or neither of these condition apply:
+ * we trap accesses to the HW, but still use it
+ * after correcting the physical offset
+ */
+ if (!has_cntpoff() && timer_get_offset(map->direct_ptimer))
+ tpt = tpc = true;
+
+ /*
+ * Apply the enable bits that the guest hypervisor has requested for
+ * its own guest. We can only add traps that wouldn't have been set
+ * above.
+ */
+ if (vcpu_has_nv(vcpu) && !is_hyp_ctxt(vcpu)) {
+ u64 val = __vcpu_sys_reg(vcpu, CNTHCTL_EL2);
+
+ /* Use the VHE format for mental sanity */
+ if (!vcpu_el2_e2h_is_set(vcpu))
+ val = (val & (CNTHCTL_EL1PCEN | CNTHCTL_EL1PCTEN)) << 10;
+
+ tpt |= !(val & (CNTHCTL_EL1PCEN << 10));
+ tpc |= !(val & (CNTHCTL_EL1PCTEN << 10));
+ }
+
+ /*
+ * Now that we have collected our requirements, compute the
+ * trap and enable bits.
+ */
+ set = 0;
+ clr = 0;
+
+ assign_clear_set_bit(tpt, CNTHCTL_EL1PCEN << 10, set, clr);
+ assign_clear_set_bit(tpc, CNTHCTL_EL1PCTEN << 10, set, clr);
+
+ /* This only happens on VHE, so use the CNTHCTL_EL2 accessor. */
+ sysreg_clear_set(cnthctl_el2, clr, set);
+}
+
+void kvm_timer_vcpu_load(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_cpu *timer = vcpu_timer(vcpu);
+ struct timer_map map;
+
+ if (unlikely(!timer->enabled))
+ return;
+
+ get_timer_map(vcpu, &map);
+
+ if (static_branch_likely(&has_gic_active_state)) {
+ if (vcpu_has_nv(vcpu))
+ kvm_timer_vcpu_load_nested_switch(vcpu, &map);
+
+ kvm_timer_vcpu_load_gic(map.direct_vtimer);
+ if (map.direct_ptimer)
+ kvm_timer_vcpu_load_gic(map.direct_ptimer);
+ } else {
+ kvm_timer_vcpu_load_nogic(vcpu);
+ }
+
+ kvm_timer_unblocking(vcpu);
+
+ timer_restore_state(map.direct_vtimer);
+ if (map.direct_ptimer)
+ timer_restore_state(map.direct_ptimer);
+ if (map.emul_vtimer)
+ timer_emulate(map.emul_vtimer);
+ if (map.emul_ptimer)
+ timer_emulate(map.emul_ptimer);
+
+ timer_set_traps(vcpu, &map);
+}
+
+bool kvm_timer_should_notify_user(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
+ struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
+ struct kvm_sync_regs *sregs = &vcpu->run->s.regs;
+ bool vlevel, plevel;
+
+ if (likely(irqchip_in_kernel(vcpu->kvm)))
+ return false;
+
+ vlevel = sregs->device_irq_level & KVM_ARM_DEV_EL1_VTIMER;
+ plevel = sregs->device_irq_level & KVM_ARM_DEV_EL1_PTIMER;
+
+ return kvm_timer_should_fire(vtimer) != vlevel ||
+ kvm_timer_should_fire(ptimer) != plevel;
+}
+
+void kvm_timer_vcpu_put(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_cpu *timer = vcpu_timer(vcpu);
+ struct timer_map map;
+
+ if (unlikely(!timer->enabled))
+ return;
+
+ get_timer_map(vcpu, &map);
+
+ timer_save_state(map.direct_vtimer);
+ if (map.direct_ptimer)
+ timer_save_state(map.direct_ptimer);
+
+ /*
+ * Cancel soft timer emulation, because the only case where we
+ * need it after a vcpu_put is in the context of a sleeping VCPU, and
+ * in that case we already factor in the deadline for the physical
+ * timer when scheduling the bg_timer.
+ *
+ * In any case, we re-schedule the hrtimer for the physical timer when
+ * coming back to the VCPU thread in kvm_timer_vcpu_load().
+ */
+ if (map.emul_vtimer)
+ soft_timer_cancel(&map.emul_vtimer->hrtimer);
+ if (map.emul_ptimer)
+ soft_timer_cancel(&map.emul_ptimer->hrtimer);
+
+ if (kvm_vcpu_is_blocking(vcpu))
+ kvm_timer_blocking(vcpu);
+}
+
+/*
+ * With a userspace irqchip we have to check if the guest de-asserted the
+ * timer and if so, unmask the timer irq signal on the host interrupt
+ * controller to ensure that we see future timer signals.
+ */
+static void unmask_vtimer_irq_user(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
+
+ if (!kvm_timer_should_fire(vtimer)) {
+ kvm_timer_update_irq(vcpu, false, vtimer);
+ if (static_branch_likely(&has_gic_active_state))
+ set_timer_irq_phys_active(vtimer, false);
+ else
+ enable_percpu_irq(host_vtimer_irq, host_vtimer_irq_flags);
+ }
+}
+
+void kvm_timer_sync_user(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_cpu *timer = vcpu_timer(vcpu);
+
+ if (unlikely(!timer->enabled))
+ return;
+
+ if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
+ unmask_vtimer_irq_user(vcpu);
+}
+
+int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_cpu *timer = vcpu_timer(vcpu);
+ struct timer_map map;
+
+ get_timer_map(vcpu, &map);
+
+ /*
+ * The bits in CNTV_CTL are architecturally reset to UNKNOWN for ARMv8
+ * and to 0 for ARMv7. We provide an implementation that always
+ * resets the timer to be disabled and unmasked and is compliant with
+ * the ARMv7 architecture.
+ */
+ for (int i = 0; i < nr_timers(vcpu); i++)
+ timer_set_ctl(vcpu_get_timer(vcpu, i), 0);
+
+ /*
+ * A vcpu running at EL2 is in charge of the offset applied to
+ * the virtual timer, so use the physical VM offset, and point
+ * the vcpu offset to CNTVOFF_EL2.
+ */
+ if (vcpu_has_nv(vcpu)) {
+ struct arch_timer_offset *offs = &vcpu_vtimer(vcpu)->offset;
+
+ offs->vcpu_offset = &__vcpu_sys_reg(vcpu, CNTVOFF_EL2);
+ offs->vm_offset = &vcpu->kvm->arch.timer_data.poffset;
+ }
+
+ if (timer->enabled) {
+ for (int i = 0; i < nr_timers(vcpu); i++)
+ kvm_timer_update_irq(vcpu, false,
+ vcpu_get_timer(vcpu, i));
+
+ if (irqchip_in_kernel(vcpu->kvm)) {
+ kvm_vgic_reset_mapped_irq(vcpu, timer_irq(map.direct_vtimer));
+ if (map.direct_ptimer)
+ kvm_vgic_reset_mapped_irq(vcpu, timer_irq(map.direct_ptimer));
+ }
+ }
+
+ if (map.emul_vtimer)
+ soft_timer_cancel(&map.emul_vtimer->hrtimer);
+ if (map.emul_ptimer)
+ soft_timer_cancel(&map.emul_ptimer->hrtimer);
+
+ return 0;
+}
+
+static void timer_context_init(struct kvm_vcpu *vcpu, int timerid)
+{
+ struct arch_timer_context *ctxt = vcpu_get_timer(vcpu, timerid);
+ struct kvm *kvm = vcpu->kvm;
+
+ ctxt->vcpu = vcpu;
+
+ if (timerid == TIMER_VTIMER)
+ ctxt->offset.vm_offset = &kvm->arch.timer_data.voffset;
+ else
+ ctxt->offset.vm_offset = &kvm->arch.timer_data.poffset;
+
+ hrtimer_init(&ctxt->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
+ ctxt->hrtimer.function = kvm_hrtimer_expire;
+
+ switch (timerid) {
+ case TIMER_PTIMER:
+ case TIMER_HPTIMER:
+ ctxt->host_timer_irq = host_ptimer_irq;
+ break;
+ case TIMER_VTIMER:
+ case TIMER_HVTIMER:
+ ctxt->host_timer_irq = host_vtimer_irq;
+ break;
+ }
+}
+
+void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_cpu *timer = vcpu_timer(vcpu);
+
+ for (int i = 0; i < NR_KVM_TIMERS; i++)
+ timer_context_init(vcpu, i);
+
+ /* Synchronize offsets across timers of a VM if not already provided */
+ if (!test_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET, &vcpu->kvm->arch.flags)) {
+ timer_set_offset(vcpu_vtimer(vcpu), kvm_phys_timer_read());
+ timer_set_offset(vcpu_ptimer(vcpu), 0);
+ }
+
+ hrtimer_init(&timer->bg_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
+ timer->bg_timer.function = kvm_bg_timer_expire;
+}
+
+void kvm_timer_init_vm(struct kvm *kvm)
+{
+ for (int i = 0; i < NR_KVM_TIMERS; i++)
+ kvm->arch.timer_data.ppi[i] = default_ppi[i];
+}
+
+void kvm_timer_cpu_up(void)
+{
+ enable_percpu_irq(host_vtimer_irq, host_vtimer_irq_flags);
+ if (host_ptimer_irq)
+ enable_percpu_irq(host_ptimer_irq, host_ptimer_irq_flags);
+}
+
+void kvm_timer_cpu_down(void)
+{
+ disable_percpu_irq(host_vtimer_irq);
+ if (host_ptimer_irq)
+ disable_percpu_irq(host_ptimer_irq);
+}
+
+int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value)
+{
+ struct arch_timer_context *timer;
+
+ switch (regid) {
+ case KVM_REG_ARM_TIMER_CTL:
+ timer = vcpu_vtimer(vcpu);
+ kvm_arm_timer_write(vcpu, timer, TIMER_REG_CTL, value);
+ break;
+ case KVM_REG_ARM_TIMER_CNT:
+ if (!test_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET,
+ &vcpu->kvm->arch.flags)) {
+ timer = vcpu_vtimer(vcpu);
+ timer_set_offset(timer, kvm_phys_timer_read() - value);
+ }
+ break;
+ case KVM_REG_ARM_TIMER_CVAL:
+ timer = vcpu_vtimer(vcpu);
+ kvm_arm_timer_write(vcpu, timer, TIMER_REG_CVAL, value);
+ break;
+ case KVM_REG_ARM_PTIMER_CTL:
+ timer = vcpu_ptimer(vcpu);
+ kvm_arm_timer_write(vcpu, timer, TIMER_REG_CTL, value);
+ break;
+ case KVM_REG_ARM_PTIMER_CNT:
+ if (!test_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET,
+ &vcpu->kvm->arch.flags)) {
+ timer = vcpu_ptimer(vcpu);
+ timer_set_offset(timer, kvm_phys_timer_read() - value);
+ }
+ break;
+ case KVM_REG_ARM_PTIMER_CVAL:
+ timer = vcpu_ptimer(vcpu);
+ kvm_arm_timer_write(vcpu, timer, TIMER_REG_CVAL, value);
+ break;
+
+ default:
+ return -1;
+ }
+
+ return 0;
+}
+
+static u64 read_timer_ctl(struct arch_timer_context *timer)
+{
+ /*
+ * Set ISTATUS bit if it's expired.
+ * Note that according to ARMv8 ARM Issue A.k, ISTATUS bit is
+ * UNKNOWN when ENABLE bit is 0, so we chose to set ISTATUS bit
+ * regardless of ENABLE bit for our implementation convenience.
+ */
+ u32 ctl = timer_get_ctl(timer);
+
+ if (!kvm_timer_compute_delta(timer))
+ ctl |= ARCH_TIMER_CTRL_IT_STAT;
+
+ return ctl;
+}
+
+u64 kvm_arm_timer_get_reg(struct kvm_vcpu *vcpu, u64 regid)
+{
+ switch (regid) {
+ case KVM_REG_ARM_TIMER_CTL:
+ return kvm_arm_timer_read(vcpu,
+ vcpu_vtimer(vcpu), TIMER_REG_CTL);
+ case KVM_REG_ARM_TIMER_CNT:
+ return kvm_arm_timer_read(vcpu,
+ vcpu_vtimer(vcpu), TIMER_REG_CNT);
+ case KVM_REG_ARM_TIMER_CVAL:
+ return kvm_arm_timer_read(vcpu,
+ vcpu_vtimer(vcpu), TIMER_REG_CVAL);
+ case KVM_REG_ARM_PTIMER_CTL:
+ return kvm_arm_timer_read(vcpu,
+ vcpu_ptimer(vcpu), TIMER_REG_CTL);
+ case KVM_REG_ARM_PTIMER_CNT:
+ return kvm_arm_timer_read(vcpu,
+ vcpu_ptimer(vcpu), TIMER_REG_CNT);
+ case KVM_REG_ARM_PTIMER_CVAL:
+ return kvm_arm_timer_read(vcpu,
+ vcpu_ptimer(vcpu), TIMER_REG_CVAL);
+ }
+ return (u64)-1;
+}
+
+static u64 kvm_arm_timer_read(struct kvm_vcpu *vcpu,
+ struct arch_timer_context *timer,
+ enum kvm_arch_timer_regs treg)
+{
+ u64 val;
+
+ switch (treg) {
+ case TIMER_REG_TVAL:
+ val = timer_get_cval(timer) - kvm_phys_timer_read() + timer_get_offset(timer);
+ val = lower_32_bits(val);
+ break;
+
+ case TIMER_REG_CTL:
+ val = read_timer_ctl(timer);
+ break;
+
+ case TIMER_REG_CVAL:
+ val = timer_get_cval(timer);
+ break;
+
+ case TIMER_REG_CNT:
+ val = kvm_phys_timer_read() - timer_get_offset(timer);
+ break;
+
+ case TIMER_REG_VOFF:
+ val = *timer->offset.vcpu_offset;
+ break;
+
+ default:
+ BUG();
+ }
+
+ return val;
+}
+
+u64 kvm_arm_timer_read_sysreg(struct kvm_vcpu *vcpu,
+ enum kvm_arch_timers tmr,
+ enum kvm_arch_timer_regs treg)
+{
+ struct arch_timer_context *timer;
+ struct timer_map map;
+ u64 val;
+
+ get_timer_map(vcpu, &map);
+ timer = vcpu_get_timer(vcpu, tmr);
+
+ if (timer == map.emul_vtimer || timer == map.emul_ptimer)
+ return kvm_arm_timer_read(vcpu, timer, treg);
+
+ preempt_disable();
+ timer_save_state(timer);
+
+ val = kvm_arm_timer_read(vcpu, timer, treg);
+
+ timer_restore_state(timer);
+ preempt_enable();
+
+ return val;
+}
+
+static void kvm_arm_timer_write(struct kvm_vcpu *vcpu,
+ struct arch_timer_context *timer,
+ enum kvm_arch_timer_regs treg,
+ u64 val)
+{
+ switch (treg) {
+ case TIMER_REG_TVAL:
+ timer_set_cval(timer, kvm_phys_timer_read() - timer_get_offset(timer) + (s32)val);
+ break;
+
+ case TIMER_REG_CTL:
+ timer_set_ctl(timer, val & ~ARCH_TIMER_CTRL_IT_STAT);
+ break;
+
+ case TIMER_REG_CVAL:
+ timer_set_cval(timer, val);
+ break;
+
+ case TIMER_REG_VOFF:
+ *timer->offset.vcpu_offset = val;
+ break;
+
+ default:
+ BUG();
+ }
+}
+
+void kvm_arm_timer_write_sysreg(struct kvm_vcpu *vcpu,
+ enum kvm_arch_timers tmr,
+ enum kvm_arch_timer_regs treg,
+ u64 val)
+{
+ struct arch_timer_context *timer;
+ struct timer_map map;
+
+ get_timer_map(vcpu, &map);
+ timer = vcpu_get_timer(vcpu, tmr);
+ if (timer == map.emul_vtimer || timer == map.emul_ptimer) {
+ soft_timer_cancel(&timer->hrtimer);
+ kvm_arm_timer_write(vcpu, timer, treg, val);
+ timer_emulate(timer);
+ } else {
+ preempt_disable();
+ timer_save_state(timer);
+ kvm_arm_timer_write(vcpu, timer, treg, val);
+ timer_restore_state(timer);
+ preempt_enable();
+ }
+}
+
+static int timer_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
+{
+ if (vcpu)
+ irqd_set_forwarded_to_vcpu(d);
+ else
+ irqd_clr_forwarded_to_vcpu(d);
+
+ return 0;
+}
+
+static int timer_irq_set_irqchip_state(struct irq_data *d,
+ enum irqchip_irq_state which, bool val)
+{
+ if (which != IRQCHIP_STATE_ACTIVE || !irqd_is_forwarded_to_vcpu(d))
+ return irq_chip_set_parent_state(d, which, val);
+
+ if (val)
+ irq_chip_mask_parent(d);
+ else
+ irq_chip_unmask_parent(d);
+
+ return 0;
+}
+
+static void timer_irq_eoi(struct irq_data *d)
+{
+ if (!irqd_is_forwarded_to_vcpu(d))
+ irq_chip_eoi_parent(d);
+}
+
+static void timer_irq_ack(struct irq_data *d)
+{
+ d = d->parent_data;
+ if (d->chip->irq_ack)
+ d->chip->irq_ack(d);
+}
+
+static struct irq_chip timer_chip = {
+ .name = "KVM",
+ .irq_ack = timer_irq_ack,
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_eoi = timer_irq_eoi,
+ .irq_set_type = irq_chip_set_type_parent,
+ .irq_set_vcpu_affinity = timer_irq_set_vcpu_affinity,
+ .irq_set_irqchip_state = timer_irq_set_irqchip_state,
+};
+
+static int timer_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
+{
+ irq_hw_number_t hwirq = (uintptr_t)arg;
+
+ return irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
+ &timer_chip, NULL);
+}
+
+static void timer_irq_domain_free(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs)
+{
+}
+
+static const struct irq_domain_ops timer_domain_ops = {
+ .alloc = timer_irq_domain_alloc,
+ .free = timer_irq_domain_free,
+};
+
+static void kvm_irq_fixup_flags(unsigned int virq, u32 *flags)
+{
+ *flags = irq_get_trigger_type(virq);
+ if (*flags != IRQF_TRIGGER_HIGH && *flags != IRQF_TRIGGER_LOW) {
+ kvm_err("Invalid trigger for timer IRQ%d, assuming level low\n",
+ virq);
+ *flags = IRQF_TRIGGER_LOW;
+ }
+}
+
+static int kvm_irq_init(struct arch_timer_kvm_info *info)
+{
+ struct irq_domain *domain = NULL;
+
+ if (info->virtual_irq <= 0) {
+ kvm_err("kvm_arch_timer: invalid virtual timer IRQ: %d\n",
+ info->virtual_irq);
+ return -ENODEV;
+ }
+
+ host_vtimer_irq = info->virtual_irq;
+ kvm_irq_fixup_flags(host_vtimer_irq, &host_vtimer_irq_flags);
+
+ if (kvm_vgic_global_state.no_hw_deactivation) {
+ struct fwnode_handle *fwnode;
+ struct irq_data *data;
+
+ fwnode = irq_domain_alloc_named_fwnode("kvm-timer");
+ if (!fwnode)
+ return -ENOMEM;
+
+ /* Assume both vtimer and ptimer in the same parent */
+ data = irq_get_irq_data(host_vtimer_irq);
+ domain = irq_domain_create_hierarchy(data->domain, 0,
+ NR_KVM_TIMERS, fwnode,
+ &timer_domain_ops, NULL);
+ if (!domain) {
+ irq_domain_free_fwnode(fwnode);
+ return -ENOMEM;
+ }
+
+ arch_timer_irq_ops.flags |= VGIC_IRQ_SW_RESAMPLE;
+ WARN_ON(irq_domain_push_irq(domain, host_vtimer_irq,
+ (void *)TIMER_VTIMER));
+ }
+
+ if (info->physical_irq > 0) {
+ host_ptimer_irq = info->physical_irq;
+ kvm_irq_fixup_flags(host_ptimer_irq, &host_ptimer_irq_flags);
+
+ if (domain)
+ WARN_ON(irq_domain_push_irq(domain, host_ptimer_irq,
+ (void *)TIMER_PTIMER));
+ }
+
+ return 0;
+}
+
+int __init kvm_timer_hyp_init(bool has_gic)
+{
+ struct arch_timer_kvm_info *info;
+ int err;
+
+ info = arch_timer_get_kvm_info();
+ timecounter = &info->timecounter;
+
+ if (!timecounter->cc) {
+ kvm_err("kvm_arch_timer: uninitialized timecounter\n");
+ return -ENODEV;
+ }
+
+ err = kvm_irq_init(info);
+ if (err)
+ return err;
+
+ /* First, do the virtual EL1 timer irq */
+
+ err = request_percpu_irq(host_vtimer_irq, kvm_arch_timer_handler,
+ "kvm guest vtimer", kvm_get_running_vcpus());
+ if (err) {
+ kvm_err("kvm_arch_timer: can't request vtimer interrupt %d (%d)\n",
+ host_vtimer_irq, err);
+ return err;
+ }
+
+ if (has_gic) {
+ err = irq_set_vcpu_affinity(host_vtimer_irq,
+ kvm_get_running_vcpus());
+ if (err) {
+ kvm_err("kvm_arch_timer: error setting vcpu affinity\n");
+ goto out_free_vtimer_irq;
+ }
+
+ static_branch_enable(&has_gic_active_state);
+ }
+
+ kvm_debug("virtual timer IRQ%d\n", host_vtimer_irq);
+
+ /* Now let's do the physical EL1 timer irq */
+
+ if (info->physical_irq > 0) {
+ err = request_percpu_irq(host_ptimer_irq, kvm_arch_timer_handler,
+ "kvm guest ptimer", kvm_get_running_vcpus());
+ if (err) {
+ kvm_err("kvm_arch_timer: can't request ptimer interrupt %d (%d)\n",
+ host_ptimer_irq, err);
+ goto out_free_vtimer_irq;
+ }
+
+ if (has_gic) {
+ err = irq_set_vcpu_affinity(host_ptimer_irq,
+ kvm_get_running_vcpus());
+ if (err) {
+ kvm_err("kvm_arch_timer: error setting vcpu affinity\n");
+ goto out_free_ptimer_irq;
+ }
+ }
+
+ kvm_debug("physical timer IRQ%d\n", host_ptimer_irq);
+ } else if (has_vhe()) {
+ kvm_err("kvm_arch_timer: invalid physical timer IRQ: %d\n",
+ info->physical_irq);
+ err = -ENODEV;
+ goto out_free_vtimer_irq;
+ }
+
+ return 0;
+
+out_free_ptimer_irq:
+ if (info->physical_irq > 0)
+ free_percpu_irq(host_ptimer_irq, kvm_get_running_vcpus());
+out_free_vtimer_irq:
+ free_percpu_irq(host_vtimer_irq, kvm_get_running_vcpus());
+ return err;
+}
+
+void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_cpu *timer = vcpu_timer(vcpu);
+
+ soft_timer_cancel(&timer->bg_timer);
+}
+
+static bool timer_irqs_are_valid(struct kvm_vcpu *vcpu)
+{
+ u32 ppis = 0;
+ bool valid;
+
+ mutex_lock(&vcpu->kvm->arch.config_lock);
+
+ for (int i = 0; i < nr_timers(vcpu); i++) {
+ struct arch_timer_context *ctx;
+ int irq;
+
+ ctx = vcpu_get_timer(vcpu, i);
+ irq = timer_irq(ctx);
+ if (kvm_vgic_set_owner(vcpu, irq, ctx))
+ break;
+
+ /*
+ * We know by construction that we only have PPIs, so
+ * all values are less than 32.
+ */
+ ppis |= BIT(irq);
+ }
+
+ valid = hweight32(ppis) == nr_timers(vcpu);
+
+ if (valid)
+ set_bit(KVM_ARCH_FLAG_TIMER_PPIS_IMMUTABLE, &vcpu->kvm->arch.flags);
+
+ mutex_unlock(&vcpu->kvm->arch.config_lock);
+
+ return valid;
+}
+
+static bool kvm_arch_timer_get_input_level(int vintid)
+{
+ struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
+
+ if (WARN(!vcpu, "No vcpu context!\n"))
+ return false;
+
+ for (int i = 0; i < nr_timers(vcpu); i++) {
+ struct arch_timer_context *ctx;
+
+ ctx = vcpu_get_timer(vcpu, i);
+ if (timer_irq(ctx) == vintid)
+ return kvm_timer_should_fire(ctx);
+ }
+
+ /* A timer IRQ has fired, but no matching timer was found? */
+ WARN_RATELIMIT(1, "timer INTID%d unknown\n", vintid);
+
+ return false;
+}
+
+int kvm_timer_enable(struct kvm_vcpu *vcpu)
+{
+ struct arch_timer_cpu *timer = vcpu_timer(vcpu);
+ struct timer_map map;
+ int ret;
+
+ if (timer->enabled)
+ return 0;
+
+ /* Without a VGIC we do not map virtual IRQs to physical IRQs */
+ if (!irqchip_in_kernel(vcpu->kvm))
+ goto no_vgic;
+
+ /*
+ * At this stage, we have the guarantee that the vgic is both
+ * available and initialized.
+ */
+ if (!timer_irqs_are_valid(vcpu)) {
+ kvm_debug("incorrectly configured timer irqs\n");
+ return -EINVAL;
+ }
+
+ get_timer_map(vcpu, &map);
+
+ ret = kvm_vgic_map_phys_irq(vcpu,
+ map.direct_vtimer->host_timer_irq,
+ timer_irq(map.direct_vtimer),
+ &arch_timer_irq_ops);
+ if (ret)
+ return ret;
+
+ if (map.direct_ptimer) {
+ ret = kvm_vgic_map_phys_irq(vcpu,
+ map.direct_ptimer->host_timer_irq,
+ timer_irq(map.direct_ptimer),
+ &arch_timer_irq_ops);
+ }
+
+ if (ret)
+ return ret;
+
+no_vgic:
+ timer->enabled = 1;
+ return 0;
+}
+
+/* If we have CNTPOFF, permanently set ECV to enable it */
+void kvm_timer_init_vhe(void)
+{
+ if (cpus_have_final_cap(ARM64_HAS_ECV_CNTPOFF))
+ sysreg_clear_set(cnthctl_el2, 0, CNTHCTL_ECV);
+}
+
+int kvm_arm_timer_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
+{
+ int __user *uaddr = (int __user *)(long)attr->addr;
+ int irq, idx, ret = 0;
+
+ if (!irqchip_in_kernel(vcpu->kvm))
+ return -EINVAL;
+
+ if (get_user(irq, uaddr))
+ return -EFAULT;
+
+ if (!(irq_is_ppi(irq)))
+ return -EINVAL;
+
+ mutex_lock(&vcpu->kvm->arch.config_lock);
+
+ if (test_bit(KVM_ARCH_FLAG_TIMER_PPIS_IMMUTABLE,
+ &vcpu->kvm->arch.flags)) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ switch (attr->attr) {
+ case KVM_ARM_VCPU_TIMER_IRQ_VTIMER:
+ idx = TIMER_VTIMER;
+ break;
+ case KVM_ARM_VCPU_TIMER_IRQ_PTIMER:
+ idx = TIMER_PTIMER;
+ break;
+ case KVM_ARM_VCPU_TIMER_IRQ_HVTIMER:
+ idx = TIMER_HVTIMER;
+ break;
+ case KVM_ARM_VCPU_TIMER_IRQ_HPTIMER:
+ idx = TIMER_HPTIMER;
+ break;
+ default:
+ ret = -ENXIO;
+ goto out;
+ }
+
+ /*
+ * We cannot validate the IRQ unicity before we run, so take it at
+ * face value. The verdict will be given on first vcpu run, for each
+ * vcpu. Yes this is late. Blame it on the stupid API.
+ */
+ vcpu->kvm->arch.timer_data.ppi[idx] = irq;
+
+out:
+ mutex_unlock(&vcpu->kvm->arch.config_lock);
+ return ret;
+}
+
+int kvm_arm_timer_get_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
+{
+ int __user *uaddr = (int __user *)(long)attr->addr;
+ struct arch_timer_context *timer;
+ int irq;
+
+ switch (attr->attr) {
+ case KVM_ARM_VCPU_TIMER_IRQ_VTIMER:
+ timer = vcpu_vtimer(vcpu);
+ break;
+ case KVM_ARM_VCPU_TIMER_IRQ_PTIMER:
+ timer = vcpu_ptimer(vcpu);
+ break;
+ case KVM_ARM_VCPU_TIMER_IRQ_HVTIMER:
+ timer = vcpu_hvtimer(vcpu);
+ break;
+ case KVM_ARM_VCPU_TIMER_IRQ_HPTIMER:
+ timer = vcpu_hptimer(vcpu);
+ break;
+ default:
+ return -ENXIO;
+ }
+
+ irq = timer_irq(timer);
+ return put_user(irq, uaddr);
+}
+
+int kvm_arm_timer_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
+{
+ switch (attr->attr) {
+ case KVM_ARM_VCPU_TIMER_IRQ_VTIMER:
+ case KVM_ARM_VCPU_TIMER_IRQ_PTIMER:
+ case KVM_ARM_VCPU_TIMER_IRQ_HVTIMER:
+ case KVM_ARM_VCPU_TIMER_IRQ_HPTIMER:
+ return 0;
+ }
+
+ return -ENXIO;
+}
+
+int kvm_vm_ioctl_set_counter_offset(struct kvm *kvm,
+ struct kvm_arm_counter_offset *offset)
+{
+ int ret = 0;
+
+ if (offset->reserved)
+ return -EINVAL;
+
+ mutex_lock(&kvm->lock);
+
+ if (lock_all_vcpus(kvm)) {
+ set_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET, &kvm->arch.flags);
+
+ /*
+ * If userspace decides to set the offset using this
+ * API rather than merely restoring the counter
+ * values, the offset applies to both the virtual and
+ * physical views.
+ */
+ kvm->arch.timer_data.voffset = offset->counter_offset;
+ kvm->arch.timer_data.poffset = offset->counter_offset;
+
+ unlock_all_vcpus(kvm);
+ } else {
+ ret = -EBUSY;
+ }
+
+ mutex_unlock(&kvm->lock);
+
+ return ret;
+}