diff options
| -rw-r--r-- | Documentation/virtual/kvm/devices/arm-vgic.txt | 52 | ||||
| -rw-r--r-- | arch/arm/include/uapi/asm/kvm.h | 6 | ||||
| -rw-r--r-- | virt/kvm/arm/vgic.c | 178 |
3 files changed, 236 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/devices/arm-vgic.txt b/Documentation/virtual/kvm/devices/arm-vgic.txt index c9febb2a0c3e..7f4e91b1316b 100644 --- a/Documentation/virtual/kvm/devices/arm-vgic.txt +++ b/Documentation/virtual/kvm/devices/arm-vgic.txt @@ -19,3 +19,55 @@ Groups: KVM_VGIC_V2_ADDR_TYPE_CPU (rw, 64-bit) Base address in the guest physical address space of the GIC virtual cpu interface register mappings. + + KVM_DEV_ARM_VGIC_GRP_DIST_REGS + Attributes: + The attr field of kvm_device_attr encodes two values: + bits: | 63 .... 40 | 39 .. 32 | 31 .... 0 | + values: | reserved | cpu id | offset | + + All distributor regs are (rw, 32-bit) + + The offset is relative to the "Distributor base address" as defined in the + GICv2 specs. Getting or setting such a register has the same effect as + reading or writing the register on the actual hardware from the cpu + specified with cpu id field. Note that most distributor fields are not + banked, but return the same value regardless of the cpu id used to access + the register. + Limitations: + - Priorities are not implemented, and registers are RAZ/WI + Errors: + -ENODEV: Getting or setting this register is not yet supported + -EBUSY: One or more VCPUs are running + + KVM_DEV_ARM_VGIC_GRP_CPU_REGS + Attributes: + The attr field of kvm_device_attr encodes two values: + bits: | 63 .... 40 | 39 .. 32 | 31 .... 0 | + values: | reserved | cpu id | offset | + + All CPU interface regs are (rw, 32-bit) + + The offset specifies the offset from the "CPU interface base address" as + defined in the GICv2 specs. Getting or setting such a register has the + same effect as reading or writing the register on the actual hardware. + + The Active Priorities Registers APRn are implementation defined, so we set a + fixed format for our implementation that fits with the model of a "GICv2 + implementation without the security extensions" which we present to the + guest. This interface always exposes four register APR[0-3] describing the + maximum possible 128 preemption levels. The semantics of the register + indicate if any interrupts in a given preemption level are in the active + state by setting the corresponding bit. + + Thus, preemption level X has one or more active interrupts if and only if: + + APRn[X mod 32] == 0b1, where n = X / 32 + + Bits for undefined preemption levels are RAZ/WI. + + Limitations: + - Priorities are not implemented, and registers are RAZ/WI + Errors: + -ENODEV: Getting or setting this register is not yet supported + -EBUSY: One or more VCPUs are running diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h index 76a742769e2b..ef0c8785ba16 100644 --- a/arch/arm/include/uapi/asm/kvm.h +++ b/arch/arm/include/uapi/asm/kvm.h @@ -165,6 +165,12 @@ struct kvm_arch_memory_slot { /* Device Control API: ARM VGIC */ #define KVM_DEV_ARM_VGIC_GRP_ADDR 0 +#define KVM_DEV_ARM_VGIC_GRP_DIST_REGS 1 +#define KVM_DEV_ARM_VGIC_GRP_CPU_REGS 2 +#define KVM_DEV_ARM_VGIC_CPUID_SHIFT 32 +#define KVM_DEV_ARM_VGIC_CPUID_MASK (0xffULL << KVM_DEV_ARM_VGIC_CPUID_SHIFT) +#define KVM_DEV_ARM_VGIC_OFFSET_SHIFT 0 +#define KVM_DEV_ARM_VGIC_OFFSET_MASK (0xffffffffULL << KVM_DEV_ARM_VGIC_OFFSET_SHIFT) /* KVM_IRQ_LINE irq field index values */ #define KVM_ARM_IRQ_TYPE_SHIFT 24 diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index e2596f618281..88599b585362 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -589,6 +589,20 @@ static bool handle_mmio_sgi_reg(struct kvm_vcpu *vcpu, return false; } +static bool handle_mmio_sgi_clear(struct kvm_vcpu *vcpu, + struct kvm_exit_mmio *mmio, + phys_addr_t offset) +{ + return false; +} + +static bool handle_mmio_sgi_set(struct kvm_vcpu *vcpu, + struct kvm_exit_mmio *mmio, + phys_addr_t offset) +{ + return false; +} + /* * I would have liked to use the kvm_bus_io_*() API instead, but it * cannot cope with banked registers (only the VM pointer is passed @@ -663,6 +677,16 @@ static const struct mmio_range vgic_dist_ranges[] = { .len = 4, .handle_mmio = handle_mmio_sgi_reg, }, + { + .base = GIC_DIST_SGI_PENDING_CLEAR, + .len = VGIC_NR_SGIS, + .handle_mmio = handle_mmio_sgi_clear, + }, + { + .base = GIC_DIST_SGI_PENDING_SET, + .len = VGIC_NR_SGIS, + .handle_mmio = handle_mmio_sgi_set, + }, {} }; @@ -1557,6 +1581,114 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write) return r; } +static bool handle_cpu_mmio_misc(struct kvm_vcpu *vcpu, + struct kvm_exit_mmio *mmio, phys_addr_t offset) +{ + return true; +} + +static const struct mmio_range vgic_cpu_ranges[] = { + { + .base = GIC_CPU_CTRL, + .len = 12, + .handle_mmio = handle_cpu_mmio_misc, + }, + { + .base = GIC_CPU_ALIAS_BINPOINT, + .len = 4, + .handle_mmio = handle_cpu_mmio_misc, + }, + { + .base = GIC_CPU_ACTIVEPRIO, + .len = 16, + .handle_mmio = handle_cpu_mmio_misc, + }, + { + .base = GIC_CPU_IDENT, + .len = 4, + .handle_mmio = handle_cpu_mmio_misc, + }, +}; + +static int vgic_attr_regs_access(struct kvm_device *dev, + struct kvm_device_attr *attr, + u32 *reg, bool is_write) +{ + const struct mmio_range *r = NULL, *ranges; + phys_addr_t offset; + int ret, cpuid, c; + struct kvm_vcpu *vcpu, *tmp_vcpu; + struct vgic_dist *vgic; + struct kvm_exit_mmio mmio; + + offset = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK; + cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >> + KVM_DEV_ARM_VGIC_CPUID_SHIFT; + + mutex_lock(&dev->kvm->lock); + + if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) { + ret = -EINVAL; + goto out; + } + + vcpu = kvm_get_vcpu(dev->kvm, cpuid); + vgic = &dev->kvm->arch.vgic; + + mmio.len = 4; + mmio.is_write = is_write; + if (is_write) + mmio_data_write(&mmio, ~0, *reg); + switch (attr->group) { + case KVM_DEV_ARM_VGIC_GRP_DIST_REGS: + mmio.phys_addr = vgic->vgic_dist_base + offset; + ranges = vgic_dist_ranges; + break; + case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: + mmio.phys_addr = vgic->vgic_cpu_base + offset; + ranges = vgic_cpu_ranges; + break; + default: + BUG(); + } + r = find_matching_range(ranges, &mmio, offset); + + if (unlikely(!r || !r->handle_mmio)) { + ret = -ENXIO; + goto out; + } + + + spin_lock(&vgic->lock); + + /* + * Ensure that no other VCPU is running by checking the vcpu->cpu + * field. If no other VPCUs are running we can safely access the VGIC + * state, because even if another VPU is run after this point, that + * VCPU will not touch the vgic state, because it will block on + * getting the vgic->lock in kvm_vgic_sync_hwstate(). + */ + kvm_for_each_vcpu(c, tmp_vcpu, dev->kvm) { + if (unlikely(tmp_vcpu->cpu != -1)) { + ret = -EBUSY; + goto out_vgic_unlock; + } + } + + offset -= r->base; + r->handle_mmio(vcpu, &mmio, offset); + + if (!is_write) + *reg = mmio_data_read(&mmio, ~0); + + ret = 0; +out_vgic_unlock: + spin_unlock(&vgic->lock); +out: + mutex_unlock(&dev->kvm->lock); + return ret; +} + static int vgic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr) { int r; @@ -1573,6 +1705,18 @@ static int vgic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr) r = kvm_vgic_addr(dev->kvm, type, &addr, true); return (r == -ENODEV) ? -ENXIO : r; } + + 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, ®, true); + } + } return -ENXIO; @@ -1594,14 +1738,42 @@ static int vgic_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr) if (copy_to_user(uaddr, &addr, sizeof(addr))) return -EFAULT; + break; + } + + 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; + + r = vgic_attr_regs_access(dev, attr, ®, false); + if (r) + return r; + r = put_user(reg, uaddr); + break; } + } return r; } +static int vgic_has_attr_regs(const struct mmio_range *ranges, + phys_addr_t offset) +{ + struct kvm_exit_mmio dev_attr_mmio; + + dev_attr_mmio.len = 4; + if (find_matching_range(ranges, &dev_attr_mmio, offset)) + return 0; + else + return -ENXIO; +} + static int vgic_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr) { + phys_addr_t offset; + switch (attr->group) { case KVM_DEV_ARM_VGIC_GRP_ADDR: switch (attr->attr) { @@ -1610,6 +1782,12 @@ static int vgic_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr) return 0; } break; + case KVM_DEV_ARM_VGIC_GRP_DIST_REGS: + offset = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK; + return vgic_has_attr_regs(vgic_dist_ranges, offset); + case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: + offset = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK; + return vgic_has_attr_regs(vgic_cpu_ranges, offset); } return -ENXIO; } |