[S390] Add support for memory hot-add.
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 6d0d3165..5dc8f80 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -313,6 +313,10 @@
config ARCH_SELECT_MEMORY_MODEL
def_bool y
+config ARCH_ENABLE_MEMORY_HOTPLUG
+ def_bool y
+ depends on SPARSEMEM
+
source "mm/Kconfig"
comment "I/O subsystem configuration"
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 0559864..388cc74 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -202,3 +202,22 @@
}
}
#endif
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+int arch_add_memory(int nid, u64 start, u64 size)
+{
+ struct pglist_data *pgdat;
+ struct zone *zone;
+ int rc;
+
+ pgdat = NODE_DATA(nid);
+ zone = pgdat->node_zones + ZONE_NORMAL;
+ rc = vmem_add_mapping(start, size);
+ if (rc)
+ return rc;
+ rc = __add_pages(zone, PFN_DOWN(start), PFN_DOWN(size));
+ if (rc)
+ vmem_remove_mapping(start, size);
+ return rc;
+}
+#endif /* CONFIG_MEMORY_HOTPLUG */