[S390] topology: expose core identifier

Provide a topology_core_id define which makes sure that the contents of
/sys/devices/system/cpu/cpuX/topology/core_id
indeed do contain the core id and not always 0.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/topology.h b/arch/s390/include/asm/topology.h
index 6e7211a..dc8a672 100644
--- a/arch/s390/include/asm/topology.h
+++ b/arch/s390/include/asm/topology.h
@@ -7,8 +7,10 @@
 
 const struct cpumask *cpu_coregroup_mask(unsigned int cpu);
 
+extern unsigned char cpu_core_id[NR_CPUS];
 extern cpumask_t cpu_core_map[NR_CPUS];
 
+#define topology_core_id(cpu)		(cpu_core_id[cpu])
 #define topology_core_cpumask(cpu)	(&cpu_core_map[cpu])
 
 int topology_set_cpu_management(int fc);
diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c
index 247b4c2..bcef007 100644
--- a/arch/s390/kernel/topology.c
+++ b/arch/s390/kernel/topology.c
@@ -37,7 +37,8 @@
 };
 
 struct tl_container {
-	unsigned char reserved[8];
+	unsigned char reserved[7];
+	unsigned char id;
 };
 
 union tl_entry {
@@ -58,6 +59,7 @@
 
 struct core_info {
 	struct core_info *next;
+	unsigned char id;
 	cpumask_t mask;
 };
 
@@ -73,6 +75,7 @@
 static DEFINE_SPINLOCK(topology_lock);
 
 cpumask_t cpu_core_map[NR_CPUS];
+unsigned char cpu_core_id[NR_CPUS];
 
 static cpumask_t cpu_coregroup_map(unsigned int cpu)
 {
@@ -116,6 +119,7 @@
 		for_each_present_cpu(lcpu) {
 			if (cpu_logical_map(lcpu) == rcpu) {
 				cpu_set(lcpu, core->mask);
+				cpu_core_id[lcpu] = core->id;
 				smp_cpu_polarization[lcpu] = tl_cpu->pp;
 			}
 		}
@@ -158,6 +162,7 @@
 			break;
 		case 1:
 			core = core->next;
+			core->id = tle->container.id;
 			break;
 		case 0:
 			add_cpus_to_core(&tle->cpu, core);