From 49776faf93f8074bb4990beac04781a9507d3650 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= Date: Fri, 16 Dec 2016 16:10:02 +0100 Subject: [PATCH] KVM: x86: decouple irqchip_in_kernel() and pic_irqchip() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit irqchip_in_kernel() tried to save a bit by reusing pic_irqchip(), but it just complicated the code. Add a separate state for the irqchip mode. Reviewed-by: David Hildenbrand [Used Paolo's version of condition in irqchip_in_kernel().] Signed-off-by: Radim Krčmář --- arch/x86/include/asm/kvm_host.h | 8 +++++++- arch/x86/kvm/irq.h | 15 ++++++++------- arch/x86/kvm/x86.c | 5 +++-- 3 files changed, 18 insertions(+), 10 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index a7066dc1a7e9..fc03ab1f6110 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -716,6 +716,12 @@ struct kvm_hv { HV_REFERENCE_TSC_PAGE tsc_ref; }; +enum kvm_irqchip_mode { + KVM_IRQCHIP_NONE, + KVM_IRQCHIP_KERNEL, /* created with KVM_CREATE_IRQCHIP */ + KVM_IRQCHIP_SPLIT, /* created with KVM_CAP_SPLIT_IRQCHIP */ +}; + struct kvm_arch { unsigned int n_used_mmu_pages; unsigned int n_requested_mmu_pages; @@ -788,7 +794,7 @@ struct kvm_arch { u64 disabled_quirks; - bool irqchip_split; + enum kvm_irqchip_mode irqchip_mode; u8 nr_reserved_ioapic_pins; bool disabled_lapic_found; diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h index 035731eb3897..f4965bc2613c 100644 --- a/arch/x86/kvm/irq.h +++ b/arch/x86/kvm/irq.h @@ -93,18 +93,19 @@ static inline int pic_in_kernel(struct kvm *kvm) static inline int irqchip_split(struct kvm *kvm) { - return kvm->arch.irqchip_split; + return kvm->arch.irqchip_mode == KVM_IRQCHIP_SPLIT; } -static inline int irqchip_in_kernel(struct kvm *kvm) +static inline int irqchip_kernel(struct kvm *kvm) { - struct kvm_pic *vpic = pic_irqchip(kvm); - bool ret; + return kvm->arch.irqchip_mode == KVM_IRQCHIP_KERNEL; +} - ret = (vpic != NULL); - ret |= irqchip_split(kvm); +static inline int irqchip_in_kernel(struct kvm *kvm) +{ + bool ret = kvm->arch.irqchip_mode != KVM_IRQCHIP_NONE; - /* Read vpic before kvm->irq_routing. */ + /* Matches with wmb after initializing kvm->irq_routing. */ smp_rmb(); return ret; } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c72a8d00a1c0..0630ab438bd5 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3894,7 +3894,7 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, goto split_irqchip_unlock; /* Pairs with irqchip_in_kernel. */ smp_wmb(); - kvm->arch.irqchip_split = true; + kvm->arch.irqchip_mode = KVM_IRQCHIP_SPLIT; kvm->arch.nr_reserved_ioapic_pins = cap->args[0]; r = 0; split_irqchip_unlock: @@ -3988,8 +3988,9 @@ long kvm_arch_vm_ioctl(struct file *filp, mutex_unlock(&kvm->slots_lock); goto create_irqchip_unlock; } - /* Write kvm->irq_routing before kvm->arch.vpic. */ + /* Write kvm->irq_routing before enabling irqchip_in_kernel. */ smp_wmb(); + kvm->arch.irqchip_mode = KVM_IRQCHIP_KERNEL; kvm->arch.vpic = vpic; create_irqchip_unlock: mutex_unlock(&kvm->lock); -- 2.20.1