diff options
Diffstat (limited to 'virt/kvm/arm/vgic.c')
| -rw-r--r-- | virt/kvm/arm/vgic.c | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 8802ad73467f..e968179e592f 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -32,6 +32,8 @@ #include <asm/kvm_arm.h> #include <asm/kvm_mmu.h> #include <trace/events/kvm.h> +#include <asm/kvm.h> +#include <kvm/iodev.h> /* * How the whole thing works (courtesy of Christoffer Dall): @@ -837,6 +839,66 @@ bool vgic_handle_mmio_range(struct kvm_vcpu *vcpu, struct kvm_run *run, } /** + * vgic_handle_mmio_access - handle an in-kernel MMIO access + * This is called by the read/write KVM IO device wrappers below. + * @vcpu: pointer to the vcpu performing the access + * @this: pointer to the KVM IO device in charge + * @addr: guest physical address of the access + * @len: size of the access + * @val: pointer to the data region + * @is_write: read or write access + * + * returns true if the MMIO access could be performed + */ +static int vgic_handle_mmio_access(struct kvm_vcpu *vcpu, + struct kvm_io_device *this, gpa_t addr, + int len, void *val, bool is_write) +{ + struct vgic_dist *dist = &vcpu->kvm->arch.vgic; + struct vgic_io_device *iodev = container_of(this, + struct vgic_io_device, dev); + struct kvm_run *run = vcpu->run; + const struct vgic_io_range *range; + struct kvm_exit_mmio mmio; + bool updated_state; + gpa_t offset; + + offset = addr - iodev->addr; + range = vgic_find_range(iodev->reg_ranges, len, offset); + if (unlikely(!range || !range->handle_mmio)) { + pr_warn("Unhandled access %d %08llx %d\n", is_write, addr, len); + return -ENXIO; + } + + mmio.phys_addr = addr; + mmio.len = len; + mmio.is_write = is_write; + if (is_write) + memcpy(mmio.data, val, len); + mmio.private = iodev->redist_vcpu; + + spin_lock(&dist->lock); + offset -= range->base; + if (vgic_validate_access(dist, range, offset)) { + updated_state = call_range_handler(vcpu, &mmio, offset, range); + if (!is_write) + memcpy(val, mmio.data, len); + } else { + if (!is_write) + memset(val, 0, len); + updated_state = false; + } + spin_unlock(&dist->lock); + kvm_prepare_mmio(run, &mmio); + kvm_handle_mmio_return(vcpu, run); + + if (updated_state) + vgic_kick_vcpus(vcpu->kvm); + + return 0; +} + +/** * vgic_handle_mmio - handle an in-kernel MMIO access for the GIC emulation * @vcpu: pointer to the vcpu performing the access * @run: pointer to the kvm_run structure @@ -860,6 +922,73 @@ bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run, return vcpu->kvm->arch.vgic.vm_ops.handle_mmio(vcpu, run, mmio); } +static int vgic_handle_mmio_read(struct kvm_vcpu *vcpu, + struct kvm_io_device *this, + gpa_t addr, int len, void *val) +{ + return vgic_handle_mmio_access(vcpu, this, addr, len, val, false); +} + +static int vgic_handle_mmio_write(struct kvm_vcpu *vcpu, + struct kvm_io_device *this, + gpa_t addr, int len, const void *val) +{ + return vgic_handle_mmio_access(vcpu, this, addr, len, (void *)val, + true); +} + +struct kvm_io_device_ops vgic_io_ops = { + .read = vgic_handle_mmio_read, + .write = vgic_handle_mmio_write, +}; + +/** + * vgic_register_kvm_io_dev - register VGIC register frame on the KVM I/O bus + * @kvm: The VM structure pointer + * @base: The (guest) base address for the register frame + * @len: Length of the register frame window + * @ranges: Describing the handler functions for each register + * @redist_vcpu_id: The VCPU ID to pass on to the handlers on call + * @iodev: Points to memory to be passed on to the handler + * + * @iodev stores the parameters of this function to be usable by the handler + * respectively the dispatcher function (since the KVM I/O bus framework lacks + * an opaque parameter). Initialization is done in this function, but the + * reference should be valid and unique for the whole VGIC lifetime. + * If the register frame is not mapped for a specific VCPU, pass -1 to + * @redist_vcpu_id. + */ +int vgic_register_kvm_io_dev(struct kvm *kvm, gpa_t base, int len, + const struct vgic_io_range *ranges, + int redist_vcpu_id, + struct vgic_io_device *iodev) +{ + struct kvm_vcpu *vcpu = NULL; + int ret; + + if (redist_vcpu_id >= 0) + vcpu = kvm_get_vcpu(kvm, redist_vcpu_id); + + iodev->addr = base; + iodev->len = len; + iodev->reg_ranges = ranges; + iodev->redist_vcpu = vcpu; + + kvm_iodevice_init(&iodev->dev, &vgic_io_ops); + + mutex_lock(&kvm->slots_lock); + + ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, base, len, + &iodev->dev); + mutex_unlock(&kvm->slots_lock); + + /* Mark the iodev as invalid if registration fails. */ + if (ret) + iodev->dev.ops = NULL; + + return ret; +} + static int vgic_nr_shared_irqs(struct vgic_dist *dist) { return dist->nr_irqs - VGIC_NR_PRIVATE_IRQS; |