Merge tag 'kvm-arm-for-4-7-take2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-next

KVM/ARM Changes for v4.7 take 2

"The GIC is dead; Long live the GIC"

This set of changes include the new vgic, which is a reimplementation of
our horribly broken legacy vgic implementation.  The two implementations
will live side-by-side (with the new being the configured default) for
one kernel release and then we'll remove it.

Also fixes a non-critical issue with virtual abort injection to guests.

1 files changed, 330 insertions, 0 deletions

diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
new file mode 100644
index 000000000000..336a46115937
--- /dev/null
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -0,0 +1,330 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/irqchip/arm-gic-v3.h>
+#include <linux/kvm.h>
+#include <linux/kvm_host.h>
+#include <kvm/arm_vgic.h>
+#include <asm/kvm_mmu.h>
+#include <asm/kvm_asm.h>
+
+#include "vgic.h"
+
+void vgic_v3_process_maintenance(struct kvm_vcpu *vcpu)
+{
+	struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;
+	u32 model = vcpu->kvm->arch.vgic.vgic_model;
+
+	if (cpuif->vgic_misr & ICH_MISR_EOI) {
+		unsigned long eisr_bmap = cpuif->vgic_eisr;
+		int lr;
+
+		for_each_set_bit(lr, &eisr_bmap, kvm_vgic_global_state.nr_lr) {
+			u32 intid;
+			u64 val = cpuif->vgic_lr[lr];
+
+			if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
+				intid = val & ICH_LR_VIRTUAL_ID_MASK;
+			else
+				intid = val & GICH_LR_VIRTUALID;
+
+			WARN_ON(cpuif->vgic_lr[lr] & ICH_LR_STATE);
+
+			kvm_notify_acked_irq(vcpu->kvm, 0,
+					     intid - VGIC_NR_PRIVATE_IRQS);
+		}
+
+		/*
+		 * In the next iterations of the vcpu loop, if we sync
+		 * the vgic state after flushing it, but before
+		 * entering the guest (this happens for pending
+		 * signals and vmid rollovers), then make sure we
+		 * don't pick up any old maintenance interrupts here.
+		 */
+		cpuif->vgic_eisr = 0;
+	}
+
+	cpuif->vgic_hcr &= ~ICH_HCR_UIE;
+}
+
+void vgic_v3_set_underflow(struct kvm_vcpu *vcpu)
+{
+	struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;
+
+	cpuif->vgic_hcr |= ICH_HCR_UIE;
+}
+
+void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
+{
+	struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3;
+	u32 model = vcpu->kvm->arch.vgic.vgic_model;
+	int lr;
+
+	for (lr = 0; lr < vcpu->arch.vgic_cpu.used_lrs; lr++) {
+		u64 val = cpuif->vgic_lr[lr];
+		u32 intid;
+		struct vgic_irq *irq;
+
+		if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
+			intid = val & ICH_LR_VIRTUAL_ID_MASK;
+		else
+			intid = val & GICH_LR_VIRTUALID;
+		irq = vgic_get_irq(vcpu->kvm, vcpu, intid);
+
+		spin_lock(&irq->irq_lock);
+
+		/* Always preserve the active bit */
+		irq->active = !!(val & ICH_LR_ACTIVE_BIT);
+
+		/* Edge is the only case where we preserve the pending bit */
+		if (irq->config == VGIC_CONFIG_EDGE &&
+		    (val & ICH_LR_PENDING_BIT)) {
+			irq->pending = true;
+
+			if (vgic_irq_is_sgi(intid) &&
+			    model == KVM_DEV_TYPE_ARM_VGIC_V2) {
+				u32 cpuid = val & GICH_LR_PHYSID_CPUID;
+
+				cpuid >>= GICH_LR_PHYSID_CPUID_SHIFT;
+				irq->source |= (1 << cpuid);
+			}
+		}
+
+		/* Clear soft pending state when level irqs have been acked */
+		if (irq->config == VGIC_CONFIG_LEVEL &&
+		    !(val & ICH_LR_PENDING_BIT)) {
+			irq->soft_pending = false;
+			irq->pending = irq->line_level;
+		}
+
+		spin_unlock(&irq->irq_lock);
+	}
+}
+
+/* Requires the irq to be locked already */
+void vgic_v3_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr)
+{
+	u32 model = vcpu->kvm->arch.vgic.vgic_model;
+	u64 val = irq->intid;
+
+	if (irq->pending) {
+		val |= ICH_LR_PENDING_BIT;
+
+		if (irq->config == VGIC_CONFIG_EDGE)
+			irq->pending = false;
+
+		if (vgic_irq_is_sgi(irq->intid) &&
+		    model == KVM_DEV_TYPE_ARM_VGIC_V2) {
+			u32 src = ffs(irq->source);
+
+			BUG_ON(!src);
+			val |= (src - 1) << GICH_LR_PHYSID_CPUID_SHIFT;
+			irq->source &= ~(1 << (src - 1));
+			if (irq->source)
+				irq->pending = true;
+		}
+	}
+
+	if (irq->active)
+		val |= ICH_LR_ACTIVE_BIT;
+
+	if (irq->hw) {
+		val |= ICH_LR_HW;
+		val |= ((u64)irq->hwintid) << ICH_LR_PHYS_ID_SHIFT;
+	} else {
+		if (irq->config == VGIC_CONFIG_LEVEL)
+			val |= ICH_LR_EOI;
+	}
+
+	/*
+	 * We currently only support Group1 interrupts, which is a
+	 * known defect. This needs to be addressed at some point.
+	 */
+	if (model == KVM_DEV_TYPE_ARM_VGIC_V3)
+		val |= ICH_LR_GROUP;
+
+	val |= (u64)irq->priority << ICH_LR_PRIORITY_SHIFT;
+
+	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = val;
+}
+
+void vgic_v3_clear_lr(struct kvm_vcpu *vcpu, int lr)
+{
+	vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[lr] = 0;
+}
+
+void vgic_v3_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
+{
+	u32 vmcr;
+
+	vmcr  = (vmcrp->ctlr << ICH_VMCR_CTLR_SHIFT) & ICH_VMCR_CTLR_MASK;
+	vmcr |= (vmcrp->abpr << ICH_VMCR_BPR1_SHIFT) & ICH_VMCR_BPR1_MASK;
+	vmcr |= (vmcrp->bpr << ICH_VMCR_BPR0_SHIFT) & ICH_VMCR_BPR0_MASK;
+	vmcr |= (vmcrp->pmr << ICH_VMCR_PMR_SHIFT) & ICH_VMCR_PMR_MASK;
+
+	vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr = vmcr;
+}
+
+void vgic_v3_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp)
+{
+	u32 vmcr = vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr;
+
+	vmcrp->ctlr = (vmcr & ICH_VMCR_CTLR_MASK) >> ICH_VMCR_CTLR_SHIFT;
+	vmcrp->abpr = (vmcr & ICH_VMCR_BPR1_MASK) >> ICH_VMCR_BPR1_SHIFT;
+	vmcrp->bpr  = (vmcr & ICH_VMCR_BPR0_MASK) >> ICH_VMCR_BPR0_SHIFT;
+	vmcrp->pmr  = (vmcr & ICH_VMCR_PMR_MASK) >> ICH_VMCR_PMR_SHIFT;
+}
+
+void vgic_v3_enable(struct kvm_vcpu *vcpu)
+{
+	struct vgic_v3_cpu_if *vgic_v3 = &vcpu->arch.vgic_cpu.vgic_v3;
+
+	/*
+	 * By forcing VMCR to zero, the GIC will restore the binary
+	 * points to their reset values. Anything else resets to zero
+	 * anyway.
+	 */
+	vgic_v3->vgic_vmcr = 0;
+	vgic_v3->vgic_elrsr = ~0;
+
+	/*
+	 * If we are emulating a GICv3, we do it in an non-GICv2-compatible
+	 * way, so we force SRE to 1 to demonstrate this to the guest.
+	 * This goes with the spec allowing the value to be RAO/WI.
+	 */
+	if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
+		vgic_v3->vgic_sre = ICC_SRE_EL1_SRE;
+	else
+		vgic_v3->vgic_sre = 0;
+
+	/* Get the show on the road... */
+	vgic_v3->vgic_hcr = ICH_HCR_EN;
+}
+
+/* check for overlapping regions and for regions crossing the end of memory */
+static bool vgic_v3_check_base(struct kvm *kvm)
+{
+	struct vgic_dist *d = &kvm->arch.vgic;
+	gpa_t redist_size = KVM_VGIC_V3_REDIST_SIZE;
+
+	redist_size *= atomic_read(&kvm->online_vcpus);
+
+	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base)
+		return false;
+	if (d->vgic_redist_base + redist_size < d->vgic_redist_base)
+		return false;
+
+	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= d->vgic_redist_base)
+		return true;
+	if (d->vgic_redist_base + redist_size <= d->vgic_dist_base)
+		return true;
+
+	return false;
+}
+
+int vgic_v3_map_resources(struct kvm *kvm)
+{
+	int ret = 0;
+	struct vgic_dist *dist = &kvm->arch.vgic;
+
+	if (vgic_ready(kvm))
+		goto out;
+
+	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base) ||
+	    IS_VGIC_ADDR_UNDEF(dist->vgic_redist_base)) {
+		kvm_err("Need to set vgic distributor addresses first\n");
+		ret = -ENXIO;
+		goto out;
+	}
+
+	if (!vgic_v3_check_base(kvm)) {
+		kvm_err("VGIC redist and dist frames overlap\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/*
+	 * For a VGICv3 we require the userland to explicitly initialize
+	 * the VGIC before we need to use it.
+	 */
+	if (!vgic_initialized(kvm)) {
+		ret = -EBUSY;
+		goto out;
+	}
+
+	ret = vgic_register_dist_iodev(kvm, dist->vgic_dist_base, VGIC_V3);
+	if (ret) {
+		kvm_err("Unable to register VGICv3 dist MMIO regions\n");
+		goto out;
+	}
+
+	ret = vgic_register_redist_iodevs(kvm, dist->vgic_redist_base);
+	if (ret) {
+		kvm_err("Unable to register VGICv3 redist MMIO regions\n");
+		goto out;
+	}
+
+	dist->ready = true;
+
+out:
+	if (ret)
+		kvm_vgic_destroy(kvm);
+	return ret;
+}
+
+/**
+ * vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT
+ * @node:	pointer to the DT node
+ *
+ * Returns 0 if a GICv3 has been found, returns an error code otherwise
+ */
+int vgic_v3_probe(const struct gic_kvm_info *info)
+{
+	u32 ich_vtr_el2 = kvm_call_hyp(__vgic_v3_get_ich_vtr_el2);
+
+	/*
+	 * The ListRegs field is 5 bits, but there is a architectural
+	 * maximum of 16 list registers. Just ignore bit 4...
+	 */
+	kvm_vgic_global_state.nr_lr = (ich_vtr_el2 & 0xf) + 1;
+	kvm_vgic_global_state.can_emulate_gicv2 = false;
+
+	if (!info->vcpu.start) {
+		kvm_info("GICv3: no GICV resource entry\n");
+		kvm_vgic_global_state.vcpu_base = 0;
+	} else if (!PAGE_ALIGNED(info->vcpu.start)) {
+		pr_warn("GICV physical address 0x%llx not page aligned\n",
+			(unsigned long long)info->vcpu.start);
+		kvm_vgic_global_state.vcpu_base = 0;
+	} else if (!PAGE_ALIGNED(resource_size(&info->vcpu))) {
+		pr_warn("GICV size 0x%llx not a multiple of page size 0x%lx\n",
+			(unsigned long long)resource_size(&info->vcpu),
+			PAGE_SIZE);
+		kvm_vgic_global_state.vcpu_base = 0;
+	} else {
+		kvm_vgic_global_state.vcpu_base = info->vcpu.start;
+		kvm_vgic_global_state.can_emulate_gicv2 = true;
+		kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V2);
+		kvm_info("vgic-v2@%llx\n", info->vcpu.start);
+	}
+	if (kvm_vgic_global_state.vcpu_base == 0)
+		kvm_info("disabling GICv2 emulation\n");
+	kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V3);
+
+	kvm_vgic_global_state.vctrl_base = NULL;
+	kvm_vgic_global_state.type = VGIC_V3;
+	kvm_vgic_global_state.max_gic_vcpus = VGIC_V3_MAX_CPUS;
+
+	return 0;
+}