From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Mon, 14 Jul 2008 07:59:18 +0000 (+0200)
Subject: [S390] Add support for memory hot-add.
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=421c175c4d609864350df495b34d3e99f9fb1bdd;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

[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 6d0d31651f05..5dc8f8028d52 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -313,6 +313,10 @@ config ARCH_SPARSEMEM_DEFAULT
 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 05598649b326..388cc7420055 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -202,3 +202,22 @@ void free_initrd_mem(unsigned long start, unsigned long end)
         }
 }
 #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 */
diff --git a/include/asm-s390/sparsemem.h b/include/asm-s390/sparsemem.h
index 06dfdab6c0e8..545d219e6a2d 100644
--- a/include/asm-s390/sparsemem.h
+++ b/include/asm-s390/sparsemem.h
@@ -1,15 +1,15 @@
 #ifndef _ASM_S390_SPARSEMEM_H
 #define _ASM_S390_SPARSEMEM_H
 
-#define SECTION_SIZE_BITS	25
-
 #ifdef CONFIG_64BIT
 
+#define SECTION_SIZE_BITS	28
 #define MAX_PHYSADDR_BITS	42
 #define MAX_PHYSMEM_BITS	42
 
 #else
 
+#define SECTION_SIZE_BITS	25
 #define MAX_PHYSADDR_BITS	31
 #define MAX_PHYSMEM_BITS	31
 
diff --git a/mm/Kconfig b/mm/Kconfig
index 3aa819d628c1..4242743b981b 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -129,7 +129,7 @@ config MEMORY_HOTPLUG
 	bool "Allow for memory hot-add"
 	depends on SPARSEMEM || X86_64_ACPI_NUMA
 	depends on HOTPLUG && !HIBERNATION && ARCH_ENABLE_MEMORY_HOTPLUG
-	depends on (IA64 || X86 || PPC64 || SUPERH)
+	depends on (IA64 || X86 || PPC64 || SUPERH || S390)
 
 comment "Memory hotplug is currently incompatible with Software Suspend"
 	depends on SPARSEMEM && HOTPLUG && HIBERNATION