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, 455 insertions, 0 deletions

diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
new file mode 100644
index 000000000000..a0c515a412a7
--- /dev/null
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -0,0 +1,455 @@
+/*
+ * VGICv3 MMIO handling functions
+ *
+ * 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.
+ */
+
+#include <linux/irqchip/arm-gic-v3.h>
+#include <linux/kvm.h>
+#include <linux/kvm_host.h>
+#include <kvm/iodev.h>
+#include <kvm/arm_vgic.h>
+
+#include <asm/kvm_emulate.h>
+
+#include "vgic.h"
+#include "vgic-mmio.h"
+
+/* extract @num bytes at @offset bytes offset in data */
+static unsigned long extract_bytes(unsigned long data, unsigned int offset,
+				   unsigned int num)
+{
+	return (data >> (offset * 8)) & GENMASK_ULL(num * 8 - 1, 0);
+}
+
+static unsigned long vgic_mmio_read_v3_misc(struct kvm_vcpu *vcpu,
+					    gpa_t addr, unsigned int len)
+{
+	u32 value = 0;
+
+	switch (addr & 0x0c) {
+	case GICD_CTLR:
+		if (vcpu->kvm->arch.vgic.enabled)
+			value |= GICD_CTLR_ENABLE_SS_G1;
+		value |= GICD_CTLR_ARE_NS | GICD_CTLR_DS;
+		break;
+	case GICD_TYPER:
+		value = vcpu->kvm->arch.vgic.nr_spis + VGIC_NR_PRIVATE_IRQS;
+		value = (value >> 5) - 1;
+		value |= (INTERRUPT_ID_BITS_SPIS - 1) << 19;
+		break;
+	case GICD_IIDR:
+		value = (PRODUCT_ID_KVM << 24) | (IMPLEMENTER_ARM << 0);
+		break;
+	default:
+		return 0;
+	}
+
+	return value;
+}
+
+static void vgic_mmio_write_v3_misc(struct kvm_vcpu *vcpu,
+				    gpa_t addr, unsigned int len,
+				    unsigned long val)
+{
+	struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+	bool was_enabled = dist->enabled;
+
+	switch (addr & 0x0c) {
+	case GICD_CTLR:
+		dist->enabled = val & GICD_CTLR_ENABLE_SS_G1;
+
+		if (!was_enabled && dist->enabled)
+			vgic_kick_vcpus(vcpu->kvm);
+		break;
+	case GICD_TYPER:
+	case GICD_IIDR:
+		return;
+	}
+}
+
+static unsigned long vgic_mmio_read_irouter(struct kvm_vcpu *vcpu,
+					    gpa_t addr, unsigned int len)
+{
+	int intid = VGIC_ADDR_TO_INTID(addr, 64);
+	struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, NULL, intid);
+
+	if (!irq)
+		return 0;
+
+	/* The upper word is RAZ for us. */
+	if (addr & 4)
+		return 0;
+
+	return extract_bytes(READ_ONCE(irq->mpidr), addr & 7, len);
+}
+
+static void vgic_mmio_write_irouter(struct kvm_vcpu *vcpu,
+				    gpa_t addr, unsigned int len,
+				    unsigned long val)
+{
+	int intid = VGIC_ADDR_TO_INTID(addr, 64);
+	struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, NULL, intid);
+
+	if (!irq)
+		return;
+
+	/* The upper word is WI for us since we don't implement Aff3. */
+	if (addr & 4)
+		return;
+
+	spin_lock(&irq->irq_lock);
+
+	/* We only care about and preserve Aff0, Aff1 and Aff2. */
+	irq->mpidr = val & GENMASK(23, 0);
+	irq->target_vcpu = kvm_mpidr_to_vcpu(vcpu->kvm, irq->mpidr);
+
+	spin_unlock(&irq->irq_lock);
+}
+
+static unsigned long vgic_mmio_read_v3r_typer(struct kvm_vcpu *vcpu,
+					      gpa_t addr, unsigned int len)
+{
+	unsigned long mpidr = kvm_vcpu_get_mpidr_aff(vcpu);
+	int target_vcpu_id = vcpu->vcpu_id;
+	u64 value;
+
+	value = (mpidr & GENMASK(23, 0)) << 32;
+	value |= ((target_vcpu_id & 0xffff) << 8);
+	if (target_vcpu_id == atomic_read(&vcpu->kvm->online_vcpus) - 1)
+		value |= GICR_TYPER_LAST;
+
+	return extract_bytes(value, addr & 7, len);
+}
+
+static unsigned long vgic_mmio_read_v3r_iidr(struct kvm_vcpu *vcpu,
+					     gpa_t addr, unsigned int len)
+{
+	return (PRODUCT_ID_KVM << 24) | (IMPLEMENTER_ARM << 0);
+}
+
+static unsigned long vgic_mmio_read_v3_idregs(struct kvm_vcpu *vcpu,
+					      gpa_t addr, unsigned int len)
+{
+	switch (addr & 0xffff) {
+	case GICD_PIDR2:
+		/* report a GICv3 compliant implementation */
+		return 0x3b;
+	}
+
+	return 0;
+}
+
+/*
+ * The GICv3 per-IRQ registers are split to control PPIs and SGIs in the
+ * redistributors, while SPIs are covered by registers in the distributor
+ * block. Trying to set private IRQs in this block gets ignored.
+ * We take some special care here to fix the calculation of the register
+ * offset.
+ */
+#define REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(off, rd, wr, bpi, acc)	\
+	{								\
+		.reg_offset = off,					\
+		.bits_per_irq = bpi,					\
+		.len = (bpi * VGIC_NR_PRIVATE_IRQS) / 8,		\
+		.access_flags = acc,					\
+		.read = vgic_mmio_read_raz,				\
+		.write = vgic_mmio_write_wi,				\
+	}, {								\
+		.reg_offset = off + (bpi * VGIC_NR_PRIVATE_IRQS) / 8,	\
+		.bits_per_irq = bpi,					\
+		.len = (bpi * (1024 - VGIC_NR_PRIVATE_IRQS)) / 8,	\
+		.access_flags = acc,					\
+		.read = rd,						\
+		.write = wr,						\
+	}
+
+static const struct vgic_register_region vgic_v3_dist_registers[] = {
+	REGISTER_DESC_WITH_LENGTH(GICD_CTLR,
+		vgic_mmio_read_v3_misc, vgic_mmio_write_v3_misc, 16,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_IGROUPR,
+		vgic_mmio_read_rao, vgic_mmio_write_wi, 1,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ISENABLER,
+		vgic_mmio_read_enable, vgic_mmio_write_senable, 1,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ICENABLER,
+		vgic_mmio_read_enable, vgic_mmio_write_cenable, 1,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ISPENDR,
+		vgic_mmio_read_pending, vgic_mmio_write_spending, 1,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ICPENDR,
+		vgic_mmio_read_pending, vgic_mmio_write_cpending, 1,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ISACTIVER,
+		vgic_mmio_read_active, vgic_mmio_write_sactive, 1,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ICACTIVER,
+		vgic_mmio_read_active, vgic_mmio_write_cactive, 1,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_IPRIORITYR,
+		vgic_mmio_read_priority, vgic_mmio_write_priority, 8,
+		VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
+	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ITARGETSR,
+		vgic_mmio_read_raz, vgic_mmio_write_wi, 8,
+		VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
+	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_ICFGR,
+		vgic_mmio_read_config, vgic_mmio_write_config, 2,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_IGRPMODR,
+		vgic_mmio_read_raz, vgic_mmio_write_wi, 1,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_IROUTER,
+		vgic_mmio_read_irouter, vgic_mmio_write_irouter, 64,
+		VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICD_IDREGS,
+		vgic_mmio_read_v3_idregs, vgic_mmio_write_wi, 48,
+		VGIC_ACCESS_32bit),
+};
+
+static const struct vgic_register_region vgic_v3_rdbase_registers[] = {
+	REGISTER_DESC_WITH_LENGTH(GICR_CTLR,
+		vgic_mmio_read_raz, vgic_mmio_write_wi, 4,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_IIDR,
+		vgic_mmio_read_v3r_iidr, vgic_mmio_write_wi, 4,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_TYPER,
+		vgic_mmio_read_v3r_typer, vgic_mmio_write_wi, 8,
+		VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_PROPBASER,
+		vgic_mmio_read_raz, vgic_mmio_write_wi, 8,
+		VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_PENDBASER,
+		vgic_mmio_read_raz, vgic_mmio_write_wi, 8,
+		VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_IDREGS,
+		vgic_mmio_read_v3_idregs, vgic_mmio_write_wi, 48,
+		VGIC_ACCESS_32bit),
+};
+
+static const struct vgic_register_region vgic_v3_sgibase_registers[] = {
+	REGISTER_DESC_WITH_LENGTH(GICR_IGROUPR0,
+		vgic_mmio_read_rao, vgic_mmio_write_wi, 4,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_ISENABLER0,
+		vgic_mmio_read_enable, vgic_mmio_write_senable, 4,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_ICENABLER0,
+		vgic_mmio_read_enable, vgic_mmio_write_cenable, 4,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_ISPENDR0,
+		vgic_mmio_read_pending, vgic_mmio_write_spending, 4,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_ICPENDR0,
+		vgic_mmio_read_pending, vgic_mmio_write_cpending, 4,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_ISACTIVER0,
+		vgic_mmio_read_active, vgic_mmio_write_sactive, 4,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_ICACTIVER0,
+		vgic_mmio_read_active, vgic_mmio_write_cactive, 4,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_IPRIORITYR0,
+		vgic_mmio_read_priority, vgic_mmio_write_priority, 32,
+		VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_ICFGR0,
+		vgic_mmio_read_config, vgic_mmio_write_config, 8,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_IGRPMODR0,
+		vgic_mmio_read_raz, vgic_mmio_write_wi, 4,
+		VGIC_ACCESS_32bit),
+	REGISTER_DESC_WITH_LENGTH(GICR_NSACR,
+		vgic_mmio_read_raz, vgic_mmio_write_wi, 4,
+		VGIC_ACCESS_32bit),
+};
+
+unsigned int vgic_v3_init_dist_iodev(struct vgic_io_device *dev)
+{
+	dev->regions = vgic_v3_dist_registers;
+	dev->nr_regions = ARRAY_SIZE(vgic_v3_dist_registers);
+
+	kvm_iodevice_init(&dev->dev, &kvm_io_gic_ops);
+
+	return SZ_64K;
+}
+
+int vgic_register_redist_iodevs(struct kvm *kvm, gpa_t redist_base_address)
+{
+	int nr_vcpus = atomic_read(&kvm->online_vcpus);
+	struct kvm_vcpu *vcpu;
+	struct vgic_io_device *devices;
+	int c, ret = 0;
+
+	devices = kmalloc(sizeof(struct vgic_io_device) * nr_vcpus * 2,
+			  GFP_KERNEL);
+	if (!devices)
+		return -ENOMEM;
+
+	kvm_for_each_vcpu(c, vcpu, kvm) {
+		gpa_t rd_base = redist_base_address + c * SZ_64K * 2;
+		gpa_t sgi_base = rd_base + SZ_64K;
+		struct vgic_io_device *rd_dev = &devices[c * 2];
+		struct vgic_io_device *sgi_dev = &devices[c * 2 + 1];
+
+		kvm_iodevice_init(&rd_dev->dev, &kvm_io_gic_ops);
+		rd_dev->base_addr = rd_base;
+		rd_dev->regions = vgic_v3_rdbase_registers;
+		rd_dev->nr_regions = ARRAY_SIZE(vgic_v3_rdbase_registers);
+		rd_dev->redist_vcpu = vcpu;
+
+		mutex_lock(&kvm->slots_lock);
+		ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, rd_base,
+					      SZ_64K, &rd_dev->dev);
+		mutex_unlock(&kvm->slots_lock);
+
+		if (ret)
+			break;
+
+		kvm_iodevice_init(&sgi_dev->dev, &kvm_io_gic_ops);
+		sgi_dev->base_addr = sgi_base;
+		sgi_dev->regions = vgic_v3_sgibase_registers;
+		sgi_dev->nr_regions = ARRAY_SIZE(vgic_v3_sgibase_registers);
+		sgi_dev->redist_vcpu = vcpu;
+
+		mutex_lock(&kvm->slots_lock);
+		ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, sgi_base,
+					      SZ_64K, &sgi_dev->dev);
+		mutex_unlock(&kvm->slots_lock);
+		if (ret) {
+			kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS,
+						  &rd_dev->dev);
+			break;
+		}
+	}
+
+	if (ret) {
+		/* The current c failed, so we start with the previous one. */
+		for (c--; c >= 0; c--) {
+			kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS,
+						  &devices[c * 2].dev);
+			kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS,
+						  &devices[c * 2 + 1].dev);
+		}
+		kfree(devices);
+	} else {
+		kvm->arch.vgic.redist_iodevs = devices;
+	}
+
+	return ret;
+}
+
+/*
+ * Compare a given affinity (level 1-3 and a level 0 mask, from the SGI
+ * generation register ICC_SGI1R_EL1) with a given VCPU.
+ * If the VCPU's MPIDR matches, return the level0 affinity, otherwise
+ * return -1.
+ */
+static int match_mpidr(u64 sgi_aff, u16 sgi_cpu_mask, struct kvm_vcpu *vcpu)
+{
+	unsigned long affinity;
+	int level0;
+
+	/*
+	 * Split the current VCPU's MPIDR into affinity level 0 and the
+	 * rest as this is what we have to compare against.
+	 */
+	affinity = kvm_vcpu_get_mpidr_aff(vcpu);
+	level0 = MPIDR_AFFINITY_LEVEL(affinity, 0);
+	affinity &= ~MPIDR_LEVEL_MASK;
+
+	/* bail out if the upper three levels don't match */
+	if (sgi_aff != affinity)
+		return -1;
+
+	/* Is this VCPU's bit set in the mask ? */
+	if (!(sgi_cpu_mask & BIT(level0)))
+		return -1;
+
+	return level0;
+}
+
+/*
+ * The ICC_SGI* registers encode the affinity differently from the MPIDR,
+ * so provide a wrapper to use the existing defines to isolate a certain
+ * affinity level.
+ */
+#define SGI_AFFINITY_LEVEL(reg, level) \
+	((((reg) & ICC_SGI1R_AFFINITY_## level ##_MASK) \
+	>> ICC_SGI1R_AFFINITY_## level ##_SHIFT) << MPIDR_LEVEL_SHIFT(level))
+
+/**
+ * vgic_v3_dispatch_sgi - handle SGI requests from VCPUs
+ * @vcpu: The VCPU requesting a SGI
+ * @reg: The value written into the ICC_SGI1R_EL1 register by that VCPU
+ *
+ * With GICv3 (and ARE=1) CPUs trigger SGIs by writing to a system register.
+ * This will trap in sys_regs.c and call this function.
+ * This ICC_SGI1R_EL1 register contains the upper three affinity levels of the
+ * target processors as well as a bitmask of 16 Aff0 CPUs.
+ * If the interrupt routing mode bit is not set, we iterate over all VCPUs to
+ * check for matching ones. If this bit is set, we signal all, but not the
+ * calling VCPU.
+ */
+void vgic_v3_dispatch_sgi(struct kvm_vcpu *vcpu, u64 reg)
+{
+	struct kvm *kvm = vcpu->kvm;
+	struct kvm_vcpu *c_vcpu;
+	u16 target_cpus;
+	u64 mpidr;
+	int sgi, c;
+	int vcpu_id = vcpu->vcpu_id;
+	bool broadcast;
+
+	sgi = (reg & ICC_SGI1R_SGI_ID_MASK) >> ICC_SGI1R_SGI_ID_SHIFT;
+	broadcast = reg & BIT(ICC_SGI1R_IRQ_ROUTING_MODE_BIT);
+	target_cpus = (reg & ICC_SGI1R_TARGET_LIST_MASK) >> ICC_SGI1R_TARGET_LIST_SHIFT;
+	mpidr = SGI_AFFINITY_LEVEL(reg, 3);
+	mpidr |= SGI_AFFINITY_LEVEL(reg, 2);
+	mpidr |= SGI_AFFINITY_LEVEL(reg, 1);
+
+	/*
+	 * We iterate over all VCPUs to find the MPIDRs matching the request.
+	 * If we have handled one CPU, we clear its bit to detect early
+	 * if we are already finished. This avoids iterating through all
+	 * VCPUs when most of the times we just signal a single VCPU.
+	 */
+	kvm_for_each_vcpu(c, c_vcpu, kvm) {
+		struct vgic_irq *irq;
+
+		/* Exit early if we have dealt with all requested CPUs */
+		if (!broadcast && target_cpus == 0)
+			break;
+
+		/* Don't signal the calling VCPU */
+		if (broadcast && c == vcpu_id)
+			continue;
+
+		if (!broadcast) {
+			int level0;
+
+			level0 = match_mpidr(mpidr, target_cpus, c_vcpu);
+			if (level0 == -1)
+				continue;
+
+			/* remove this matching VCPU from the mask */
+			target_cpus &= ~BIT(level0);
+		}
+
+		irq = vgic_get_irq(vcpu->kvm, c_vcpu, sgi);
+
+		spin_lock(&irq->irq_lock);
+		irq->pending = true;
+
+		vgic_queue_irq_unlock(vcpu->kvm, irq);
+	}
+}