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, 431 insertions, 0 deletions

diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
new file mode 100644
index 000000000000..0130c4b147b7
--- /dev/null
+++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
@@ -0,0 +1,431 @@
+/*
+ * VGIC: KVM DEVICE API
+ *
+ * Copyright (C) 2015 ARM Ltd.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * 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/kvm_host.h>
+#include <kvm/arm_vgic.h>
+#include <linux/uaccess.h>
+#include <asm/kvm_mmu.h>
+#include "vgic.h"
+
+/* common helpers */
+
+static int vgic_check_ioaddr(struct kvm *kvm, phys_addr_t *ioaddr,
+			     phys_addr_t addr, phys_addr_t alignment)
+{
+	if (addr & ~KVM_PHYS_MASK)
+		return -E2BIG;
+
+	if (!IS_ALIGNED(addr, alignment))
+		return -EINVAL;
+
+	if (!IS_VGIC_ADDR_UNDEF(*ioaddr))
+		return -EEXIST;
+
+	return 0;
+}
+
+/**
+ * kvm_vgic_addr - set or get vgic VM base addresses
+ * @kvm:   pointer to the vm struct
+ * @type:  the VGIC addr type, one of KVM_VGIC_V[23]_ADDR_TYPE_XXX
+ * @addr:  pointer to address value
+ * @write: if true set the address in the VM address space, if false read the
+ *          address
+ *
+ * Set or get the vgic base addresses for the distributor and the virtual CPU
+ * interface in the VM physical address space.  These addresses are properties
+ * of the emulated core/SoC and therefore user space initially knows this
+ * information.
+ * Check them for sanity (alignment, double assignment). We can't check for
+ * overlapping regions in case of a virtual GICv3 here, since we don't know
+ * the number of VCPUs yet, so we defer this check to map_resources().
+ */
+int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
+{
+	int r = 0;
+	struct vgic_dist *vgic = &kvm->arch.vgic;
+	int type_needed;
+	phys_addr_t *addr_ptr, alignment;
+
+	mutex_lock(&kvm->lock);
+	switch (type) {
+	case KVM_VGIC_V2_ADDR_TYPE_DIST:
+		type_needed = KVM_DEV_TYPE_ARM_VGIC_V2;
+		addr_ptr = &vgic->vgic_dist_base;
+		alignment = SZ_4K;
+		break;
+	case KVM_VGIC_V2_ADDR_TYPE_CPU:
+		type_needed = KVM_DEV_TYPE_ARM_VGIC_V2;
+		addr_ptr = &vgic->vgic_cpu_base;
+		alignment = SZ_4K;
+		break;
+#ifdef CONFIG_KVM_ARM_VGIC_V3
+	case KVM_VGIC_V3_ADDR_TYPE_DIST:
+		type_needed = KVM_DEV_TYPE_ARM_VGIC_V3;
+		addr_ptr = &vgic->vgic_dist_base;
+		alignment = SZ_64K;
+		break;
+	case KVM_VGIC_V3_ADDR_TYPE_REDIST:
+		type_needed = KVM_DEV_TYPE_ARM_VGIC_V3;
+		addr_ptr = &vgic->vgic_redist_base;
+		alignment = SZ_64K;
+		break;
+#endif
+	default:
+		r = -ENODEV;
+		goto out;
+	}
+
+	if (vgic->vgic_model != type_needed) {
+		r = -ENODEV;
+		goto out;
+	}
+
+	if (write) {
+		r = vgic_check_ioaddr(kvm, addr_ptr, *addr, alignment);
+		if (!r)
+			*addr_ptr = *addr;
+	} else {
+		*addr = *addr_ptr;
+	}
+
+out:
+	mutex_unlock(&kvm->lock);
+	return r;
+}
+
+static int vgic_set_common_attr(struct kvm_device *dev,
+				struct kvm_device_attr *attr)
+{
+	int r;
+
+	switch (attr->group) {
+	case KVM_DEV_ARM_VGIC_GRP_ADDR: {
+		u64 __user *uaddr = (u64 __user *)(long)attr->addr;
+		u64 addr;
+		unsigned long type = (unsigned long)attr->attr;
+
+		if (copy_from_user(&addr, uaddr, sizeof(addr)))
+			return -EFAULT;
+
+		r = kvm_vgic_addr(dev->kvm, type, &addr, true);
+		return (r == -ENODEV) ? -ENXIO : r;
+	}
+	case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: {
+		u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+		u32 val;
+		int ret = 0;
+
+		if (get_user(val, uaddr))
+			return -EFAULT;
+
+		/*
+		 * We require:
+		 * - at least 32 SPIs on top of the 16 SGIs and 16 PPIs
+		 * - at most 1024 interrupts
+		 * - a multiple of 32 interrupts
+		 */
+		if (val < (VGIC_NR_PRIVATE_IRQS + 32) ||
+		    val > VGIC_MAX_RESERVED ||
+		    (val & 31))
+			return -EINVAL;
+
+		mutex_lock(&dev->kvm->lock);
+
+		if (vgic_ready(dev->kvm) || dev->kvm->arch.vgic.nr_spis)
+			ret = -EBUSY;
+		else
+			dev->kvm->arch.vgic.nr_spis =
+				val - VGIC_NR_PRIVATE_IRQS;
+
+		mutex_unlock(&dev->kvm->lock);
+
+		return ret;
+	}
+	case KVM_DEV_ARM_VGIC_GRP_CTRL: {
+		switch (attr->attr) {
+		case KVM_DEV_ARM_VGIC_CTRL_INIT:
+			mutex_lock(&dev->kvm->lock);
+			r = vgic_init(dev->kvm);
+			mutex_unlock(&dev->kvm->lock);
+			return r;
+		}
+		break;
+	}
+	}
+
+	return -ENXIO;
+}
+
+static int vgic_get_common_attr(struct kvm_device *dev,
+				struct kvm_device_attr *attr)
+{
+	int r = -ENXIO;
+
+	switch (attr->group) {
+	case KVM_DEV_ARM_VGIC_GRP_ADDR: {
+		u64 __user *uaddr = (u64 __user *)(long)attr->addr;
+		u64 addr;
+		unsigned long type = (unsigned long)attr->attr;
+
+		r = kvm_vgic_addr(dev->kvm, type, &addr, false);
+		if (r)
+			return (r == -ENODEV) ? -ENXIO : r;
+
+		if (copy_to_user(uaddr, &addr, sizeof(addr)))
+			return -EFAULT;
+		break;
+	}
+	case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: {
+		u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+
+		r = put_user(dev->kvm->arch.vgic.nr_spis +
+			     VGIC_NR_PRIVATE_IRQS, uaddr);
+		break;
+	}
+	}
+
+	return r;
+}
+
+static int vgic_create(struct kvm_device *dev, u32 type)
+{
+	return kvm_vgic_create(dev->kvm, type);
+}
+
+static void vgic_destroy(struct kvm_device *dev)
+{
+	kfree(dev);
+}
+
+void kvm_register_vgic_device(unsigned long type)
+{
+	switch (type) {
+	case KVM_DEV_TYPE_ARM_VGIC_V2:
+		kvm_register_device_ops(&kvm_arm_vgic_v2_ops,
+					KVM_DEV_TYPE_ARM_VGIC_V2);
+		break;
+#ifdef CONFIG_KVM_ARM_VGIC_V3
+	case KVM_DEV_TYPE_ARM_VGIC_V3:
+		kvm_register_device_ops(&kvm_arm_vgic_v3_ops,
+					KVM_DEV_TYPE_ARM_VGIC_V3);
+		break;
+#endif
+	}
+}
+
+/** vgic_attr_regs_access: allows user space to read/write VGIC registers
+ *
+ * @dev: kvm device handle
+ * @attr: kvm device attribute
+ * @reg: address the value is read or written
+ * @is_write: write flag
+ *
+ */
+static int vgic_attr_regs_access(struct kvm_device *dev,
+				 struct kvm_device_attr *attr,
+				 u32 *reg, bool is_write)
+{
+	gpa_t addr;
+	int cpuid, ret, c;
+	struct kvm_vcpu *vcpu, *tmp_vcpu;
+	int vcpu_lock_idx = -1;
+
+	cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >>
+		 KVM_DEV_ARM_VGIC_CPUID_SHIFT;
+	vcpu = kvm_get_vcpu(dev->kvm, cpuid);
+	addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
+
+	mutex_lock(&dev->kvm->lock);
+
+	ret = vgic_init(dev->kvm);
+	if (ret)
+		goto out;
+
+	if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/*
+	 * Any time a vcpu is run, vcpu_load is called which tries to grab the
+	 * vcpu->mutex.  By grabbing the vcpu->mutex of all VCPUs we ensure
+	 * that no other VCPUs are run and fiddle with the vgic state while we
+	 * access it.
+	 */
+	ret = -EBUSY;
+	kvm_for_each_vcpu(c, tmp_vcpu, dev->kvm) {
+		if (!mutex_trylock(&tmp_vcpu->mutex))
+			goto out;
+		vcpu_lock_idx = c;
+	}
+
+	switch (attr->group) {
+	case KVM_DEV_ARM_VGIC_GRP_CPU_REGS:
+		ret = vgic_v2_cpuif_uaccess(vcpu, is_write, addr, reg);
+		break;
+	case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
+		ret = vgic_v2_dist_uaccess(vcpu, is_write, addr, reg);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+out:
+	for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
+		tmp_vcpu = kvm_get_vcpu(dev->kvm, vcpu_lock_idx);
+		mutex_unlock(&tmp_vcpu->mutex);
+	}
+
+	mutex_unlock(&dev->kvm->lock);
+	return ret;
+}
+
+/* V2 ops */
+
+static int vgic_v2_set_attr(struct kvm_device *dev,
+			    struct kvm_device_attr *attr)
+{
+	int ret;
+
+	ret = vgic_set_common_attr(dev, attr);
+	if (ret != -ENXIO)
+		return ret;
+
+	switch (attr->group) {
+	case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
+	case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: {
+		u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+		u32 reg;
+
+		if (get_user(reg, uaddr))
+			return -EFAULT;
+
+		return vgic_attr_regs_access(dev, attr, &reg, true);
+	}
+	}
+
+	return -ENXIO;
+}
+
+static int vgic_v2_get_attr(struct kvm_device *dev,
+			    struct kvm_device_attr *attr)
+{
+	int ret;
+
+	ret = vgic_get_common_attr(dev, attr);
+	if (ret != -ENXIO)
+		return ret;
+
+	switch (attr->group) {
+	case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
+	case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: {
+		u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+		u32 reg = 0;
+
+		ret = vgic_attr_regs_access(dev, attr, &reg, false);
+		if (ret)
+			return ret;
+		return put_user(reg, uaddr);
+	}
+	}
+
+	return -ENXIO;
+}
+
+static int vgic_v2_has_attr(struct kvm_device *dev,
+			    struct kvm_device_attr *attr)
+{
+	switch (attr->group) {
+	case KVM_DEV_ARM_VGIC_GRP_ADDR:
+		switch (attr->attr) {
+		case KVM_VGIC_V2_ADDR_TYPE_DIST:
+		case KVM_VGIC_V2_ADDR_TYPE_CPU:
+			return 0;
+		}
+		break;
+	case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
+	case KVM_DEV_ARM_VGIC_GRP_CPU_REGS:
+		return vgic_v2_has_attr_regs(dev, attr);
+	case KVM_DEV_ARM_VGIC_GRP_NR_IRQS:
+		return 0;
+	case KVM_DEV_ARM_VGIC_GRP_CTRL:
+		switch (attr->attr) {
+		case KVM_DEV_ARM_VGIC_CTRL_INIT:
+			return 0;
+		}
+	}
+	return -ENXIO;
+}
+
+struct kvm_device_ops kvm_arm_vgic_v2_ops = {
+	.name = "kvm-arm-vgic-v2",
+	.create = vgic_create,
+	.destroy = vgic_destroy,
+	.set_attr = vgic_v2_set_attr,
+	.get_attr = vgic_v2_get_attr,
+	.has_attr = vgic_v2_has_attr,
+};
+
+/* V3 ops */
+
+#ifdef CONFIG_KVM_ARM_VGIC_V3
+
+static int vgic_v3_set_attr(struct kvm_device *dev,
+			    struct kvm_device_attr *attr)
+{
+	return vgic_set_common_attr(dev, attr);
+}
+
+static int vgic_v3_get_attr(struct kvm_device *dev,
+			    struct kvm_device_attr *attr)
+{
+	return vgic_get_common_attr(dev, attr);
+}
+
+static int vgic_v3_has_attr(struct kvm_device *dev,
+			    struct kvm_device_attr *attr)
+{
+	switch (attr->group) {
+	case KVM_DEV_ARM_VGIC_GRP_ADDR:
+		switch (attr->attr) {
+		case KVM_VGIC_V3_ADDR_TYPE_DIST:
+		case KVM_VGIC_V3_ADDR_TYPE_REDIST:
+			return 0;
+		}
+		break;
+	case KVM_DEV_ARM_VGIC_GRP_NR_IRQS:
+		return 0;
+	case KVM_DEV_ARM_VGIC_GRP_CTRL:
+		switch (attr->attr) {
+		case KVM_DEV_ARM_VGIC_CTRL_INIT:
+			return 0;
+		}
+	}
+	return -ENXIO;
+}
+
+struct kvm_device_ops kvm_arm_vgic_v3_ops = {
+	.name = "kvm-arm-vgic-v3",
+	.create = vgic_create,
+	.destroy = vgic_destroy,
+	.set_attr = vgic_v3_set_attr,
+	.get_attr = vgic_v3_get_attr,
+	.has_attr = vgic_v3_has_attr,
+};
+
+#endif /* CONFIG_KVM_ARM_VGIC_V3 */
+