1 files changed, 284 insertions, 0 deletions
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
new file mode 100644
index 000000000..7a43b2ae1
--- /dev/null
+++ b/arch/x86/xen/smp.c
@@ -0,0 +1,284 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/smp.h>
+#include <linux/cpu.h>
+#include <linux/slab.h>
+#include <linux/cpumask.h>
+#include <linux/percpu.h>
+
+#include <xen/events.h>
+
+#include <xen/hvc-console.h>
+#include "xen-ops.h"
+#include "smp.h"
+
+static DEFINE_PER_CPU(struct xen_common_irq, xen_resched_irq) = { .irq = -1 };
+static DEFINE_PER_CPU(struct xen_common_irq, xen_callfunc_irq) = { .irq = -1 };
+static DEFINE_PER_CPU(struct xen_common_irq, xen_callfuncsingle_irq) = { .irq = -1 };
+static DEFINE_PER_CPU(struct xen_common_irq, xen_debug_irq) = { .irq = -1 };
+
+static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
+static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);
+
+/*
+ * Reschedule call back.
+ */
+static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id)
+{
+	inc_irq_stat(irq_resched_count);
+	scheduler_ipi();
+
+	return IRQ_HANDLED;
+}
+
+void xen_smp_intr_free(unsigned int cpu)
+{
+	if (per_cpu(xen_resched_irq, cpu).irq >= 0) {
+		unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu).irq, NULL);
+		per_cpu(xen_resched_irq, cpu).irq = -1;
+		kfree(per_cpu(xen_resched_irq, cpu).name);
+		per_cpu(xen_resched_irq, cpu).name = NULL;
+	}
+	if (per_cpu(xen_callfunc_irq, cpu).irq >= 0) {
+		unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu).irq, NULL);
+		per_cpu(xen_callfunc_irq, cpu).irq = -1;
+		kfree(per_cpu(xen_callfunc_irq, cpu).name);
+		per_cpu(xen_callfunc_irq, cpu).name = NULL;
+	}
+	if (per_cpu(xen_debug_irq, cpu).irq >= 0) {
+		unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu).irq, NULL);
+		per_cpu(xen_debug_irq, cpu).irq = -1;
+		kfree(per_cpu(xen_debug_irq, cpu).name);
+		per_cpu(xen_debug_irq, cpu).name = NULL;
+	}
+	if (per_cpu(xen_callfuncsingle_irq, cpu).irq >= 0) {
+		unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu).irq,
+				       NULL);
+		per_cpu(xen_callfuncsingle_irq, cpu).irq = -1;
+		kfree(per_cpu(xen_callfuncsingle_irq, cpu).name);
+		per_cpu(xen_callfuncsingle_irq, cpu).name = NULL;
+	}
+}
+
+int xen_smp_intr_init(unsigned int cpu)
+{
+	int rc;
+	char *resched_name, *callfunc_name, *debug_name;
+
+	resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu);
+	rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR,
+				    cpu,
+				    xen_reschedule_interrupt,
+				    IRQF_PERCPU|IRQF_NOBALANCING,
+				    resched_name,
+				    NULL);
+	if (rc < 0)
+		goto fail;
+	per_cpu(xen_resched_irq, cpu).irq = rc;
+	per_cpu(xen_resched_irq, cpu).name = resched_name;
+
+	callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu);
+	rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR,
+				    cpu,
+				    xen_call_function_interrupt,
+				    IRQF_PERCPU|IRQF_NOBALANCING,
+				    callfunc_name,
+				    NULL);
+	if (rc < 0)
+		goto fail;
+	per_cpu(xen_callfunc_irq, cpu).irq = rc;
+	per_cpu(xen_callfunc_irq, cpu).name = callfunc_name;
+
+	debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu);
+	rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt,
+				     IRQF_PERCPU | IRQF_NOBALANCING,
+				     debug_name, NULL);
+	if (rc < 0)
+		goto fail;
+	per_cpu(xen_debug_irq, cpu).irq = rc;
+	per_cpu(xen_debug_irq, cpu).name = debug_name;
+
+	callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu);
+	rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR,
+				    cpu,
+				    xen_call_function_single_interrupt,
+				    IRQF_PERCPU|IRQF_NOBALANCING,
+				    callfunc_name,
+				    NULL);
+	if (rc < 0)
+		goto fail;
+	per_cpu(xen_callfuncsingle_irq, cpu).irq = rc;
+	per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name;
+
+	return 0;
+
+ fail:
+	xen_smp_intr_free(cpu);
+	return rc;
+}
+
+void __init xen_smp_cpus_done(unsigned int max_cpus)
+{
+	int cpu, rc, count = 0;
+
+	if (xen_hvm_domain())
+		native_smp_cpus_done(max_cpus);
+	else
+		calculate_max_logical_packages();
+
+	if (xen_have_vcpu_info_placement)
+		return;
+
+	for_each_online_cpu(cpu) {
+		if (xen_vcpu_nr(cpu) < MAX_VIRT_CPUS)
+			continue;
+
+		rc = cpu_down(cpu);
+
+		if (rc == 0) {
+			/*
+			 * Reset vcpu_info so this cpu cannot be onlined again.
+			 */
+			xen_vcpu_info_reset(cpu);
+			count++;
+		} else {
+			pr_warn("%s: failed to bring CPU %d down, error %d\n",
+				__func__, cpu, rc);
+		}
+	}
+	WARN(count, "%s: brought %d CPUs offline\n", __func__, count);
+}
+
+void xen_smp_send_reschedule(int cpu)
+{
+	xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
+}
+
+static void __xen_send_IPI_mask(const struct cpumask *mask,
+			      int vector)
+{
+	unsigned cpu;
+
+	for_each_cpu_and(cpu, mask, cpu_online_mask)
+		xen_send_IPI_one(cpu, vector);
+}
+
+void xen_smp_send_call_function_ipi(const struct cpumask *mask)
+{
+	int cpu;
+
+	__xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR);
+
+	/* Make sure other vcpus get a chance to run if they need to. */
+	for_each_cpu(cpu, mask) {
+		if (xen_vcpu_stolen(cpu)) {
+			HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
+			break;
+		}
+	}
+}
+
+void xen_smp_send_call_function_single_ipi(int cpu)
+{
+	__xen_send_IPI_mask(cpumask_of(cpu),
+			  XEN_CALL_FUNCTION_SINGLE_VECTOR);
+}
+
+static inline int xen_map_vector(int vector)
+{
+	int xen_vector;
+
+	switch (vector) {
+	case RESCHEDULE_VECTOR:
+		xen_vector = XEN_RESCHEDULE_VECTOR;
+		break;
+	case CALL_FUNCTION_VECTOR:
+		xen_vector = XEN_CALL_FUNCTION_VECTOR;
+		break;
+	case CALL_FUNCTION_SINGLE_VECTOR:
+		xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR;
+		break;
+	case IRQ_WORK_VECTOR:
+		xen_vector = XEN_IRQ_WORK_VECTOR;
+		break;
+#ifdef CONFIG_X86_64
+	case NMI_VECTOR:
+	case APIC_DM_NMI: /* Some use that instead of NMI_VECTOR */
+		xen_vector = XEN_NMI_VECTOR;
+		break;
+#endif
+	default:
+		xen_vector = -1;
+		printk(KERN_ERR "xen: vector 0x%x is not implemented\n",
+			vector);
+	}
+
+	return xen_vector;
+}
+
+void xen_send_IPI_mask(const struct cpumask *mask,
+			      int vector)
+{
+	int xen_vector = xen_map_vector(vector);
+
+	if (xen_vector >= 0)
+		__xen_send_IPI_mask(mask, xen_vector);
+}
+
+void xen_send_IPI_all(int vector)
+{
+	int xen_vector = xen_map_vector(vector);
+
+	if (xen_vector >= 0)
+		__xen_send_IPI_mask(cpu_online_mask, xen_vector);
+}
+
+void xen_send_IPI_self(int vector)
+{
+	int xen_vector = xen_map_vector(vector);
+
+	if (xen_vector >= 0)
+		xen_send_IPI_one(smp_processor_id(), xen_vector);
+}
+
+void xen_send_IPI_mask_allbutself(const struct cpumask *mask,
+				int vector)
+{
+	unsigned cpu;
+	unsigned int this_cpu = smp_processor_id();
+	int xen_vector = xen_map_vector(vector);
+
+	if (!(num_online_cpus() > 1) || (xen_vector < 0))
+		return;
+
+	for_each_cpu_and(cpu, mask, cpu_online_mask) {
+		if (this_cpu == cpu)
+			continue;
+
+		xen_send_IPI_one(cpu, xen_vector);
+	}
+}
+
+void xen_send_IPI_allbutself(int vector)
+{
+	xen_send_IPI_mask_allbutself(cpu_online_mask, vector);
+}
+
+static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
+{
+	irq_enter();
+	generic_smp_call_function_interrupt();
+	inc_irq_stat(irq_call_count);
+	irq_exit();
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
+{
+	irq_enter();
+	generic_smp_call_function_single_interrupt();
+	inc_irq_stat(irq_call_count);
+	irq_exit();
+
+	return IRQ_HANDLED;
+}