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authorPeter Maydell <peter.maydell@linaro.org>2014-12-04 15:02:24 +0000
committerChristoffer Dall <christoffer.dall@linaro.org>2014-12-13 14:15:52 +0100
commit6d3cfbe21bef5b66530b50ad16c88fdc71a04c35 (patch)
treeb5f375258f0273acdab23d900ac9b06c642a8e5f /virt/kvm
parent957db105c99792ae8ef61ffc9ae77d910f6471da (diff)
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arm/arm64: KVM: vgic: move reset initialization into vgic_init_maps()
VGIC initialization currently happens in three phases: (1) kvm_vgic_create() (triggered by userspace GIC creation) (2) vgic_init_maps() (triggered by userspace GIC register read/write requests, or from kvm_vgic_init() if not already run) (3) kvm_vgic_init() (triggered by first VM run) We were doing initialization of some state to correspond with the state of a freshly-reset GIC in kvm_vgic_init(); this is too late, since it will overwrite changes made by userspace using the register access APIs before the VM is run. Move this initialization earlier, into the vgic_init_maps() phase. This fixes a bug where QEMU could successfully restore a saved VM state snapshot into a VM that had already been run, but could not restore it "from cold" using the -loadvm command line option (the symptoms being that the restored VM would run but interrupts were ignored). Finally rename vgic_init_maps to vgic_init and renamed kvm_vgic_init to kvm_vgic_map_resources. [ This patch is originally written by Peter Maydell, but I have modified it somewhat heavily, renaming various bits and moving code around. If something is broken, I am to be blamed. - Christoffer ] Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Diffstat (limited to 'virt/kvm')
-rw-r--r--virt/kvm/arm/vgic.c77
1 files changed, 32 insertions, 45 deletions
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index 21e035cc5460..1ce4e364c1e0 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -91,6 +91,7 @@
#define ACCESS_WRITE_VALUE (3 << 1)
#define ACCESS_WRITE_MASK(x) ((x) & (3 << 1))
+static int vgic_init(struct kvm *kvm);
static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu);
static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu);
static void vgic_update_state(struct kvm *kvm);
@@ -1732,39 +1733,14 @@ static int vgic_vcpu_init_maps(struct kvm_vcpu *vcpu, int nr_irqs)
int sz = (nr_irqs - VGIC_NR_PRIVATE_IRQS) / 8;
vgic_cpu->pending_shared = kzalloc(sz, GFP_KERNEL);
- vgic_cpu->vgic_irq_lr_map = kzalloc(nr_irqs, GFP_KERNEL);
+ vgic_cpu->vgic_irq_lr_map = kmalloc(nr_irqs, GFP_KERNEL);
if (!vgic_cpu->pending_shared || !vgic_cpu->vgic_irq_lr_map) {
kvm_vgic_vcpu_destroy(vcpu);
return -ENOMEM;
}
- return 0;
-}
-
-/**
- * kvm_vgic_vcpu_init - Initialize per-vcpu VGIC state
- * @vcpu: pointer to the vcpu struct
- *
- * Initialize the vgic_cpu struct and vgic_dist struct fields pertaining to
- * this vcpu and enable the VGIC for this 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;
-
- for (i = 0; i < dist->nr_irqs; i++) {
- if (i < VGIC_NR_PPIS)
- vgic_bitmap_set_irq_val(&dist->irq_enabled,
- vcpu->vcpu_id, i, 1);
- if (i < VGIC_NR_PRIVATE_IRQS)
- vgic_bitmap_set_irq_val(&dist->irq_cfg,
- vcpu->vcpu_id, i, VGIC_CFG_EDGE);
-
- vgic_cpu->vgic_irq_lr_map[i] = LR_EMPTY;
- }
+ memset(vgic_cpu->vgic_irq_lr_map, LR_EMPTY, nr_irqs);
/*
* Store the number of LRs per vcpu, so we don't have to go
@@ -1773,7 +1749,7 @@ static void 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)
@@ -1810,12 +1786,12 @@ void kvm_vgic_destroy(struct kvm *kvm)
* Allocate and initialize the various data structures. Must be called
* with kvm->lock held!
*/
-static int vgic_init_maps(struct kvm *kvm)
+static int vgic_init(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct kvm_vcpu *vcpu;
int nr_cpus, nr_irqs;
- int ret, i;
+ int ret, i, vcpu_id;
if (dist->nr_cpus) /* Already allocated */
return 0;
@@ -1865,16 +1841,28 @@ static int vgic_init_maps(struct kvm *kvm)
if (ret)
goto out;
- kvm_for_each_vcpu(i, vcpu, kvm) {
+ for (i = VGIC_NR_PRIVATE_IRQS; i < dist->nr_irqs; i += 4)
+ vgic_set_target_reg(kvm, 0, i);
+
+ kvm_for_each_vcpu(vcpu_id, vcpu, kvm) {
ret = vgic_vcpu_init_maps(vcpu, nr_irqs);
if (ret) {
kvm_err("VGIC: Failed to allocate vcpu memory\n");
break;
}
- }
- for (i = VGIC_NR_PRIVATE_IRQS; i < dist->nr_irqs; i += 4)
- vgic_set_target_reg(kvm, 0, i);
+ for (i = 0; i < dist->nr_irqs; i++) {
+ if (i < VGIC_NR_PPIS)
+ vgic_bitmap_set_irq_val(&dist->irq_enabled,
+ vcpu->vcpu_id, i, 1);
+ if (i < VGIC_NR_PRIVATE_IRQS)
+ vgic_bitmap_set_irq_val(&dist->irq_cfg,
+ vcpu->vcpu_id, i,
+ VGIC_CFG_EDGE);
+ }
+
+ vgic_enable(vcpu);
+ }
out:
if (ret)
@@ -1884,18 +1872,16 @@ out:
}
/**
- * kvm_vgic_init - Initialize global VGIC state before running any VCPUs
+ * kvm_vgic_map_resources - Configure global VGIC state before running any VCPUs
* @kvm: pointer to the kvm struct
*
* Map the virtual CPU interface into the VM before running any VCPUs. We
* can't do this at creation time, because user space must first set the
- * virtual CPU interface address in the guest physical address space. Also
- * initialize the ITARGETSRn regs to 0 on the emulated distributor.
+ * virtual CPU interface address in the guest physical address space.
*/
-int kvm_vgic_init(struct kvm *kvm)
+int kvm_vgic_map_resources(struct kvm *kvm)
{
- struct kvm_vcpu *vcpu;
- int ret = 0, i;
+ int ret = 0;
if (!irqchip_in_kernel(kvm))
return 0;
@@ -1912,7 +1898,11 @@ int kvm_vgic_init(struct kvm *kvm)
goto out;
}
- ret = vgic_init_maps(kvm);
+ /*
+ * Initialize the vgic if this hasn't already been done on demand by
+ * accessing the vgic state from userspace.
+ */
+ ret = vgic_init(kvm);
if (ret) {
kvm_err("Unable to allocate maps\n");
goto out;
@@ -1926,9 +1916,6 @@ int kvm_vgic_init(struct kvm *kvm)
goto out;
}
- kvm_for_each_vcpu(i, vcpu, kvm)
- kvm_vgic_vcpu_init(vcpu);
-
kvm->arch.vgic.ready = true;
out:
if (ret)
@@ -2173,7 +2160,7 @@ static int vgic_attr_regs_access(struct kvm_device *dev,
mutex_lock(&dev->kvm->lock);
- ret = vgic_init_maps(dev->kvm);
+ ret = vgic_init(dev->kvm);
if (ret)
goto out;