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-rw-r--r--virt/kvm/arm/vgic/vgic-init.c123
1 files changed, 123 insertions, 0 deletions
diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
new file mode 100644
index 000000000000..4523beb029f3
--- /dev/null
+++ b/virt/kvm/arm/vgic/vgic-init.c
@@ -0,0 +1,123 @@
+/*
+ * 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;
+}