mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-30 06:10:56 +00:00
KVM: arm64: timers: Move the timer IRQs into arch_timer_vm_data
Having the timer IRQs duplicated into each vcpu isn't great, and becomes absolutely awful with NV. So let's move these into the per-VM arch_timer_vm_data structure. This simplifies a lot of code, but requires us to introduce a mutex so that we can reason about userspace trying to change an interrupt number while another vcpu is running, something that wasn't really well handled so far. Reviewed-by: Colton Lewis <coltonlewis@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230330174800.2677007-12-maz@kernel.org
This commit is contained in:
parent
33c549460e
commit
8a5eb2d210
4 changed files with 82 additions and 48 deletions
|
@ -223,6 +223,8 @@ struct kvm_arch {
|
|||
#define KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED 5
|
||||
/* VM counter offset */
|
||||
#define KVM_ARCH_FLAG_VM_COUNTER_OFFSET 6
|
||||
/* Timer PPIs made immutable */
|
||||
#define KVM_ARCH_FLAG_TIMER_PPIS_IMMUTABLE 7
|
||||
|
||||
unsigned long flags;
|
||||
|
||||
|
|
|
@ -851,7 +851,6 @@ static void timer_context_init(struct kvm_vcpu *vcpu, int timerid)
|
|||
|
||||
hrtimer_init(&ctxt->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
|
||||
ctxt->hrtimer.function = kvm_hrtimer_expire;
|
||||
timer_irq(ctxt) = default_ppi[timerid];
|
||||
|
||||
switch (timerid) {
|
||||
case TIMER_PTIMER:
|
||||
|
@ -880,6 +879,13 @@ void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
|
|||
timer->bg_timer.function = kvm_bg_timer_expire;
|
||||
}
|
||||
|
||||
void kvm_timer_init_vm(struct kvm *kvm)
|
||||
{
|
||||
mutex_init(&kvm->arch.timer_data.lock);
|
||||
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);
|
||||
|
@ -1292,44 +1298,56 @@ void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu)
|
|||
|
||||
static bool timer_irqs_are_valid(struct kvm_vcpu *vcpu)
|
||||
{
|
||||
int vtimer_irq, ptimer_irq, ret;
|
||||
unsigned long i;
|
||||
u32 ppis = 0;
|
||||
bool valid;
|
||||
|
||||
vtimer_irq = timer_irq(vcpu_vtimer(vcpu));
|
||||
ret = kvm_vgic_set_owner(vcpu, vtimer_irq, vcpu_vtimer(vcpu));
|
||||
if (ret)
|
||||
return false;
|
||||
mutex_lock(&vcpu->kvm->arch.timer_data.lock);
|
||||
|
||||
ptimer_irq = timer_irq(vcpu_ptimer(vcpu));
|
||||
ret = kvm_vgic_set_owner(vcpu, ptimer_irq, vcpu_ptimer(vcpu));
|
||||
if (ret)
|
||||
return false;
|
||||
for (int i = 0; i < NR_KVM_TIMERS; i++) {
|
||||
struct arch_timer_context *ctx;
|
||||
int irq;
|
||||
|
||||
kvm_for_each_vcpu(i, vcpu, vcpu->kvm) {
|
||||
if (timer_irq(vcpu_vtimer(vcpu)) != vtimer_irq ||
|
||||
timer_irq(vcpu_ptimer(vcpu)) != ptimer_irq)
|
||||
return false;
|
||||
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);
|
||||
}
|
||||
|
||||
return true;
|
||||
valid = hweight32(ppis) == NR_KVM_TIMERS;
|
||||
|
||||
if (valid)
|
||||
set_bit(KVM_ARCH_FLAG_TIMER_PPIS_IMMUTABLE, &vcpu->kvm->arch.flags);
|
||||
|
||||
mutex_unlock(&vcpu->kvm->arch.timer_data.lock);
|
||||
|
||||
return valid;
|
||||
}
|
||||
|
||||
bool kvm_arch_timer_get_input_level(int vintid)
|
||||
{
|
||||
struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
|
||||
struct arch_timer_context *timer;
|
||||
|
||||
if (WARN(!vcpu, "No vcpu context!\n"))
|
||||
return false;
|
||||
|
||||
if (vintid == timer_irq(vcpu_vtimer(vcpu)))
|
||||
timer = vcpu_vtimer(vcpu);
|
||||
else if (vintid == timer_irq(vcpu_ptimer(vcpu)))
|
||||
timer = vcpu_ptimer(vcpu);
|
||||
else
|
||||
BUG();
|
||||
for (int i = 0; i < NR_KVM_TIMERS; i++) {
|
||||
struct arch_timer_context *ctx;
|
||||
|
||||
return kvm_timer_should_fire(timer);
|
||||
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)
|
||||
|
@ -1385,23 +1403,10 @@ void kvm_timer_init_vhe(void)
|
|||
sysreg_clear_set(cntkctl_el1, 0, CNTHCTL_ECV);
|
||||
}
|
||||
|
||||
static void set_timer_irqs(struct kvm *kvm, int vtimer_irq, int ptimer_irq)
|
||||
{
|
||||
struct kvm_vcpu *vcpu;
|
||||
unsigned long i;
|
||||
|
||||
kvm_for_each_vcpu(i, vcpu, kvm) {
|
||||
timer_irq(vcpu_vtimer(vcpu)) = vtimer_irq;
|
||||
timer_irq(vcpu_ptimer(vcpu)) = ptimer_irq;
|
||||
}
|
||||
}
|
||||
|
||||
int kvm_arm_timer_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
|
||||
{
|
||||
int __user *uaddr = (int __user *)(long)attr->addr;
|
||||
struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
|
||||
struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
|
||||
int irq;
|
||||
int irq, idx, ret = 0;
|
||||
|
||||
if (!irqchip_in_kernel(vcpu->kvm))
|
||||
return -EINVAL;
|
||||
|
@ -1412,21 +1417,36 @@ int kvm_arm_timer_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
|
|||
if (!(irq_is_ppi(irq)))
|
||||
return -EINVAL;
|
||||
|
||||
if (vcpu->arch.timer_cpu.enabled)
|
||||
return -EBUSY;
|
||||
mutex_lock(&vcpu->kvm->arch.timer_data.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:
|
||||
set_timer_irqs(vcpu->kvm, irq, timer_irq(ptimer));
|
||||
idx = TIMER_VTIMER;
|
||||
break;
|
||||
case KVM_ARM_VCPU_TIMER_IRQ_PTIMER:
|
||||
set_timer_irqs(vcpu->kvm, timer_irq(vtimer), irq);
|
||||
idx = TIMER_PTIMER;
|
||||
break;
|
||||
default:
|
||||
return -ENXIO;
|
||||
ret = -ENXIO;
|
||||
goto out;
|
||||
}
|
||||
|
||||
return 0;
|
||||
/*
|
||||
* 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.timer_data.lock);
|
||||
return ret;
|
||||
}
|
||||
|
||||
int kvm_arm_timer_get_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
|
||||
|
|
|
@ -148,6 +148,8 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
|
|||
|
||||
kvm_vgic_early_init(kvm);
|
||||
|
||||
kvm_timer_init_vm(kvm);
|
||||
|
||||
/* The maximum number of VCPUs is limited by the host's GIC model */
|
||||
kvm->max_vcpus = kvm_arm_default_max_vcpus();
|
||||
|
||||
|
|
|
@ -36,14 +36,16 @@ struct arch_timer_vm_data {
|
|||
u64 voffset;
|
||||
/* Offset applied to the physical timer/counter */
|
||||
u64 poffset;
|
||||
|
||||
struct mutex lock;
|
||||
|
||||
/* The PPI for each timer, global to the VM */
|
||||
u8 ppi[NR_KVM_TIMERS];
|
||||
};
|
||||
|
||||
struct arch_timer_context {
|
||||
struct kvm_vcpu *vcpu;
|
||||
|
||||
/* Timer IRQ */
|
||||
struct kvm_irq_level irq;
|
||||
|
||||
/* Emulated Timer (may be unused) */
|
||||
struct hrtimer hrtimer;
|
||||
u64 ns_frac;
|
||||
|
@ -57,6 +59,11 @@ struct arch_timer_context {
|
|||
*/
|
||||
bool loaded;
|
||||
|
||||
/* Output level of the timer IRQ */
|
||||
struct {
|
||||
bool level;
|
||||
} irq;
|
||||
|
||||
/* Duplicated state from arch_timer.c for convenience */
|
||||
u32 host_timer_irq;
|
||||
};
|
||||
|
@ -86,6 +93,8 @@ bool kvm_timer_should_notify_user(struct kvm_vcpu *vcpu);
|
|||
void kvm_timer_update_run(struct kvm_vcpu *vcpu);
|
||||
void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu);
|
||||
|
||||
void kvm_timer_init_vm(struct kvm *kvm);
|
||||
|
||||
u64 kvm_arm_timer_get_reg(struct kvm_vcpu *, u64 regid);
|
||||
int kvm_arm_timer_set_reg(struct kvm_vcpu *, u64 regid, u64 value);
|
||||
|
||||
|
@ -109,7 +118,8 @@ bool kvm_arch_timer_get_input_level(int vintid);
|
|||
|
||||
#define arch_timer_ctx_index(ctx) ((ctx) - vcpu_timer((ctx)->vcpu)->timers)
|
||||
|
||||
#define timer_irq(ctx) ((ctx)->irq.irq)
|
||||
#define timer_vm_data(ctx) (&(ctx)->vcpu->kvm->arch.timer_data)
|
||||
#define timer_irq(ctx) (timer_vm_data(ctx)->ppi[arch_timer_ctx_index(ctx)])
|
||||
|
||||
u64 kvm_arm_timer_read_sysreg(struct kvm_vcpu *vcpu,
|
||||
enum kvm_arch_timers tmr,
|
||||
|
|
Loading…
Reference in a new issue