s390: remove broken hibernate / power management support

Hibernation is known to be broken for many years on s390. Given that
there aren't any real use cases, remove the code instead of spending
time to fix and maintain it.

Without hibernate support it doesn't make too much sense to keep power
management support; therefore remove it completely.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

1 files changed, 3 insertions, 43 deletions

diff --git a/arch/s390/mm/cmm.c b/arch/s390/mm/cmm.c
index a51c892f14f3..ae989b740376 100644
--- a/arch/s390/mm/cmm.c
+++ b/arch/s390/mm/cmm.c
@@ -19,7 +19,6 @@
 #include <linux/swap.h>
 #include <linux/kthread.h>
 #include <linux/oom.h>
-#include <linux/suspend.h>
 #include <linux/uaccess.h>
 
 #include <asm/pgalloc.h>
@@ -49,7 +48,6 @@ static volatile long cmm_pages_target;
 static volatile long cmm_timed_pages_target;
 static long cmm_timeout_pages;
 static long cmm_timeout_seconds;
-static int cmm_suspended;
 
 static struct cmm_page_array *cmm_page_list;
 static struct cmm_page_array *cmm_timed_page_list;
@@ -151,9 +149,9 @@ static int cmm_thread(void *dummy)
 
 	while (1) {
 		rc = wait_event_interruptible(cmm_thread_wait,
-			(!cmm_suspended && (cmm_pages != cmm_pages_target ||
-			 cmm_timed_pages != cmm_timed_pages_target)) ||
-			 kthread_should_stop());
+			cmm_pages != cmm_pages_target ||
+			cmm_timed_pages != cmm_timed_pages_target ||
+			kthread_should_stop());
 		if (kthread_should_stop() || rc == -ERESTARTSYS) {
 			cmm_pages_target = cmm_pages;
 			cmm_timed_pages_target = cmm_timed_pages;
@@ -390,38 +388,6 @@ static void cmm_smsg_target(const char *from, char *msg)
 
 static struct ctl_table_header *cmm_sysctl_header;
 
-static int cmm_suspend(void)
-{
-	cmm_suspended = 1;
-	cmm_free_pages(cmm_pages, &cmm_pages, &cmm_page_list);
-	cmm_free_pages(cmm_timed_pages, &cmm_timed_pages, &cmm_timed_page_list);
-	return 0;
-}
-
-static int cmm_resume(void)
-{
-	cmm_suspended = 0;
-	cmm_kick_thread();
-	return 0;
-}
-
-static int cmm_power_event(struct notifier_block *this,
-			   unsigned long event, void *ptr)
-{
-	switch (event) {
-	case PM_POST_HIBERNATION:
-		return cmm_resume();
-	case PM_HIBERNATION_PREPARE:
-		return cmm_suspend();
-	default:
-		return NOTIFY_DONE;
-	}
-}
-
-static struct notifier_block cmm_power_notifier = {
-	.notifier_call = cmm_power_event,
-};
-
 static int __init cmm_init(void)
 {
 	int rc = -ENOMEM;
@@ -446,16 +412,11 @@ static int __init cmm_init(void)
 	rc = register_oom_notifier(&cmm_oom_nb);
 	if (rc < 0)
 		goto out_oom_notify;
-	rc = register_pm_notifier(&cmm_power_notifier);
-	if (rc)
-		goto out_pm;
 	cmm_thread_ptr = kthread_run(cmm_thread, NULL, "cmmthread");
 	if (!IS_ERR(cmm_thread_ptr))
 		return 0;
 
 	rc = PTR_ERR(cmm_thread_ptr);
-	unregister_pm_notifier(&cmm_power_notifier);
-out_pm:
 	unregister_oom_notifier(&cmm_oom_nb);
 out_oom_notify:
 #ifdef CONFIG_CMM_IUCV
@@ -475,7 +436,6 @@ static void __exit cmm_exit(void)
 #ifdef CONFIG_CMM_IUCV
 	smsg_unregister_callback(SMSG_PREFIX, cmm_smsg_target);
 #endif
-	unregister_pm_notifier(&cmm_power_notifier);
 	unregister_oom_notifier(&cmm_oom_nb);
 	kthread_stop(cmm_thread_ptr);
 	del_timer_sync(&cmm_timer);