[S390] pm: memory hotplug power management callbacks

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/char/sclp_cmd.c b/drivers/s390/char/sclp_cmd.c
index 77ab6e3..5cc11c6 100644
--- a/drivers/s390/char/sclp_cmd.c
+++ b/drivers/s390/char/sclp_cmd.c
@@ -1,9 +1,8 @@
 /*
- *  drivers/s390/char/sclp_cmd.c
+ * Copyright IBM Corp. 2007, 2009
  *
- *    Copyright IBM Corp. 2007
- *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
- *		 Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
+ * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
+ *	      Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
  */
 
 #define KMSG_COMPONENT "sclp_cmd"
@@ -12,11 +11,13 @@
 #include <linux/completion.h>
 #include <linux/init.h>
 #include <linux/errno.h>
+#include <linux/err.h>
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/mm.h>
 #include <linux/mmzone.h>
 #include <linux/memory.h>
+#include <linux/platform_device.h>
 #include <asm/chpid.h>
 #include <asm/sclp.h>
 #include <asm/setup.h>
@@ -292,6 +293,7 @@
 static LIST_HEAD(sclp_mem_list);
 static u8 sclp_max_storage_id;
 static unsigned long sclp_storage_ids[256 / BITS_PER_LONG];
+static int sclp_mem_state_changed;
 
 struct memory_increment {
 	struct list_head list;
@@ -450,6 +452,8 @@
 		rc = -EINVAL;
 		break;
 	}
+	if (!rc)
+		sclp_mem_state_changed = 1;
 	mutex_unlock(&sclp_mem_mutex);
 	return rc ? NOTIFY_BAD : NOTIFY_OK;
 }
@@ -525,6 +529,14 @@
 	list_add(&new_incr->list, prev);
 }
 
+static int sclp_mem_freeze(struct device *dev)
+{
+	if (!sclp_mem_state_changed)
+		return 0;
+	pr_err("Memory hotplug state changed, suspend refused.\n");
+	return -EPERM;
+}
+
 struct read_storage_sccb {
 	struct sccb_header header;
 	u16 max_id;
@@ -534,8 +546,20 @@
 	u32 entries[0];
 } __packed;
 
+static struct dev_pm_ops sclp_mem_pm_ops = {
+	.freeze		= sclp_mem_freeze,
+};
+
+static struct platform_driver sclp_mem_pdrv = {
+	.driver = {
+		.name	= "sclp_mem",
+		.pm	= &sclp_mem_pm_ops,
+	},
+};
+
 static int __init sclp_detect_standby_memory(void)
 {
+	struct platform_device *sclp_pdev;
 	struct read_storage_sccb *sccb;
 	int i, id, assigned, rc;
 
@@ -588,7 +612,17 @@
 	rc = register_memory_notifier(&sclp_mem_nb);
 	if (rc)
 		goto out;
+	rc = platform_driver_register(&sclp_mem_pdrv);
+	if (rc)
+		goto out;
+	sclp_pdev = platform_device_register_simple("sclp_mem", -1, NULL, 0);
+	rc = IS_ERR(sclp_pdev) ? PTR_ERR(sclp_pdev) : 0;
+	if (rc)
+		goto out_driver;
 	sclp_add_standby_memory();
+	goto out;
+out_driver:
+	platform_driver_unregister(&sclp_mem_pdrv);
 out:
 	free_page((unsigned long) sccb);
 	return rc;
diff --git a/mm/Kconfig b/mm/Kconfig
index 71830ba..6f4610a 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -128,11 +128,11 @@
 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 HOTPLUG && !(HIBERNATION && !S390) && ARCH_ENABLE_MEMORY_HOTPLUG
 	depends on (IA64 || X86 || PPC64 || SUPERH || S390)
 
 comment "Memory hotplug is currently incompatible with Software Suspend"
-	depends on SPARSEMEM && HOTPLUG && HIBERNATION
+	depends on SPARSEMEM && HOTPLUG && HIBERNATION && !S390
 
 config MEMORY_HOTPLUG_SPARSE
 	def_bool y