1 files changed, 35 insertions, 0 deletions

diff --git a/drivers/xen/pcpu.c b/drivers/xen/pcpu.c
index 5a27a4599a4a..6536d5ab1697 100644
--- a/drivers/xen/pcpu.c
+++ b/drivers/xen/pcpu.c
@@ -332,6 +332,41 @@ static irqreturn_t xen_pcpu_interrupt(int irq, void *dev_id)
         return IRQ_HANDLED;
 }
 
+/* Sync with Xen hypervisor after cpu hotadded */
+void xen_pcpu_hotplug_sync(void)
+{
+        schedule_work(&xen_pcpu_work);
+}
+EXPORT_SYMBOL_GPL(xen_pcpu_hotplug_sync);
+
+/*
+ * For hypervisor presented cpu, return logic cpu id;
+ * For hypervisor non-presented cpu, return -ENODEV.
+ */
+int xen_pcpu_id(uint32_t acpi_id)
+{
+        int cpu_id = 0, max_id = 0;
+        struct xen_platform_op op;
+
+        op.cmd = XENPF_get_cpuinfo;
+        while (cpu_id <= max_id) {
+                op.u.pcpu_info.xen_cpuid = cpu_id;
+                if (HYPERVISOR_dom0_op(&op)) {
+                        cpu_id++;
+                        continue;
+                }
+
+                if (acpi_id == op.u.pcpu_info.acpi_id)
+                        return cpu_id;
+                if (op.u.pcpu_info.max_present > max_id)
+                        max_id = op.u.pcpu_info.max_present;
+                cpu_id++;
+        }
+
+        return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(xen_pcpu_id);
+
 static int __init xen_pcpu_init(void)
 {
         int irq, ret;