From 4956f2bc1fdee4bc336532f3f34635a8534cedfd Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 8 Jul 2014 12:09:06 +0100 Subject: arm/arm64: KVM: vgic: delay vgic allocation until init time It is now quite easy to delay the allocation of the vgic tables until we actually require it to be up and running (when the first vcpu is kicking around, or someones tries to access the GIC registers). This allow us to allocate memory for the exact number of CPUs we have. As nobody configures the number of interrupts just yet, use a fallback to VGIC_NR_IRQS_LEGACY. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- virt/kvm/arm/vgic.c | 42 +++++++++++++++++++++++++++++------------- 1 file changed, 29 insertions(+), 13 deletions(-) (limited to 'virt') diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 725d829ad1d9..ac2b44d58e60 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1729,15 +1729,12 @@ static int vgic_vcpu_init_maps(struct kvm_vcpu *vcpu, int nr_irqs) * Initialize the vgic_cpu struct and vgic_dist struct fields pertaining to * this vcpu and enable the VGIC for this VCPU */ -int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu) +static void kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu) { struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; struct vgic_dist *dist = &vcpu->kvm->arch.vgic; int i; - if (vcpu->vcpu_id >= dist->nr_cpus) - return -EBUSY; - for (i = 0; i < dist->nr_irqs; i++) { if (i < VGIC_NR_PPIS) vgic_bitmap_set_irq_val(&dist->irq_enabled, @@ -1757,8 +1754,6 @@ int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu) vgic_cpu->nr_lr = vgic->nr_lr; vgic_enable(vcpu); - - return 0; } void kvm_vgic_destroy(struct kvm *kvm) @@ -1802,8 +1797,17 @@ static int vgic_init_maps(struct kvm *kvm) int nr_cpus, nr_irqs; int ret, i; - nr_cpus = dist->nr_cpus = KVM_MAX_VCPUS; + if (dist->nr_cpus) /* Already allocated */ + return 0; + + nr_cpus = dist->nr_cpus = atomic_read(&kvm->online_vcpus); + if (!nr_cpus) /* No vcpus? Can't be good... */ + return -EINVAL; + /* + * If nobody configured the number of interrupts, use the + * legacy one. + */ if (!dist->nr_irqs) dist->nr_irqs = VGIC_NR_IRQS_LEGACY; @@ -1849,6 +1853,9 @@ static int vgic_init_maps(struct kvm *kvm) } } + for (i = VGIC_NR_PRIVATE_IRQS; i < dist->nr_irqs; i += 4) + vgic_set_target_reg(kvm, 0, i); + out: if (ret) kvm_vgic_destroy(kvm); @@ -1867,6 +1874,7 @@ out: */ int kvm_vgic_init(struct kvm *kvm) { + struct kvm_vcpu *vcpu; int ret = 0, i; if (!irqchip_in_kernel(kvm)) @@ -1884,6 +1892,12 @@ int kvm_vgic_init(struct kvm *kvm) goto out; } + ret = vgic_init_maps(kvm); + if (ret) { + kvm_err("Unable to allocate maps\n"); + goto out; + } + ret = kvm_phys_addr_ioremap(kvm, kvm->arch.vgic.vgic_cpu_base, vgic->vcpu_base, KVM_VGIC_V2_CPU_SIZE); if (ret) { @@ -1891,11 +1905,13 @@ int kvm_vgic_init(struct kvm *kvm) goto out; } - for (i = VGIC_NR_PRIVATE_IRQS; i < kvm->arch.vgic.nr_irqs; i += 4) - vgic_set_target_reg(kvm, 0, i); + kvm_for_each_vcpu(i, vcpu, kvm) + kvm_vgic_vcpu_init(vcpu); kvm->arch.vgic.ready = true; out: + if (ret) + kvm_vgic_destroy(kvm); mutex_unlock(&kvm->lock); return ret; } @@ -1936,10 +1952,6 @@ int kvm_vgic_create(struct kvm *kvm) kvm->arch.vgic.vgic_dist_base = VGIC_ADDR_UNDEF; kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF; - ret = vgic_init_maps(kvm); - if (ret) - kvm_err("Unable to allocate maps\n"); - out_unlock: for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) { vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx); @@ -2140,6 +2152,10 @@ static int vgic_attr_regs_access(struct kvm_device *dev, mutex_lock(&dev->kvm->lock); + ret = vgic_init_maps(dev->kvm); + if (ret) + goto out; + if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) { ret = -EINVAL; goto out; -- cgit v1.2.3