| /* |
| * Copyright (C) 2015, 2016 ARM Ltd. |
| * |
| * 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/uaccess.h> |
| #include <linux/interrupt.h> |
| #include <linux/cpu.h> |
| #include <linux/kvm_host.h> |
| #include <kvm/arm_vgic.h> |
| #include <asm/kvm_mmu.h> |
| #include "vgic.h" |
| |
| /* GENERIC PROBE */ |
| |
| static void vgic_init_maintenance_interrupt(void *info) |
| { |
| enable_percpu_irq(kvm_vgic_global_state.maint_irq, 0); |
| } |
| |
| static int vgic_cpu_notify(struct notifier_block *self, |
| unsigned long action, void *cpu) |
| { |
| switch (action) { |
| case CPU_STARTING: |
| case CPU_STARTING_FROZEN: |
| vgic_init_maintenance_interrupt(NULL); |
| break; |
| case CPU_DYING: |
| case CPU_DYING_FROZEN: |
| disable_percpu_irq(kvm_vgic_global_state.maint_irq); |
| break; |
| } |
| |
| return NOTIFY_OK; |
| } |
| |
| static struct notifier_block vgic_cpu_nb = { |
| .notifier_call = vgic_cpu_notify, |
| }; |
| |
| static irqreturn_t vgic_maintenance_handler(int irq, void *data) |
| { |
| /* |
| * We cannot rely on the vgic maintenance interrupt to be |
| * delivered synchronously. This means we can only use it to |
| * exit the VM, and we perform the handling of EOIed |
| * interrupts on the exit path (see vgic_process_maintenance). |
| */ |
| return IRQ_HANDLED; |
| } |
| |
| /** |
| * kvm_vgic_hyp_init: populates the kvm_vgic_global_state variable |
| * according to the host GIC model. Accordingly calls either |
| * vgic_v2/v3_probe which registers the KVM_DEVICE that can be |
| * instantiated by a guest later on . |
| */ |
| int kvm_vgic_hyp_init(void) |
| { |
| const struct gic_kvm_info *gic_kvm_info; |
| int ret; |
| |
| gic_kvm_info = gic_get_kvm_info(); |
| if (!gic_kvm_info) |
| return -ENODEV; |
| |
| if (!gic_kvm_info->maint_irq) { |
| kvm_err("No vgic maintenance irq\n"); |
| return -ENXIO; |
| } |
| |
| switch (gic_kvm_info->type) { |
| case GIC_V2: |
| ret = vgic_v2_probe(gic_kvm_info); |
| break; |
| case GIC_V3: |
| ret = vgic_v3_probe(gic_kvm_info); |
| break; |
| default: |
| ret = -ENODEV; |
| }; |
| |
| if (ret) |
| return ret; |
| |
| kvm_vgic_global_state.maint_irq = gic_kvm_info->maint_irq; |
| ret = request_percpu_irq(kvm_vgic_global_state.maint_irq, |
| vgic_maintenance_handler, |
| "vgic", kvm_get_running_vcpus()); |
| if (ret) { |
| kvm_err("Cannot register interrupt %d\n", |
| kvm_vgic_global_state.maint_irq); |
| return ret; |
| } |
| |
| ret = __register_cpu_notifier(&vgic_cpu_nb); |
| if (ret) { |
| kvm_err("Cannot register vgic CPU notifier\n"); |
| goto out_free_irq; |
| } |
| |
| on_each_cpu(vgic_init_maintenance_interrupt, NULL, 1); |
| |
| kvm_info("vgic interrupt IRQ%d\n", kvm_vgic_global_state.maint_irq); |
| return 0; |
| |
| out_free_irq: |
| free_percpu_irq(kvm_vgic_global_state.maint_irq, |
| kvm_get_running_vcpus()); |
| return ret; |
| } |