PM: introduce hibernation and suspend notifiers
Make it possible to register hibernation and suspend notifiers, so that
subsystems can perform hibernation-related or suspend-related operations that
should not be carried out by device drivers' .suspend() and .resume()
routines.
[akpm@linux-foundation.org: build fixes]
[akpm@linux-foundation.org: cleanups]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/power/disk.c b/kernel/power/disk.c
index 885c653..324ac01 100644
--- a/kernel/power/disk.c
+++ b/kernel/power/disk.c
@@ -281,9 +281,16 @@
{
int error;
+ mutex_lock(&pm_mutex);
/* The snapshot device should not be opened while we're running */
- if (!atomic_add_unless(&snapshot_device_available, -1, 0))
- return -EBUSY;
+ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+ error = -EBUSY;
+ goto Unlock;
+ }
+
+ error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
+ if (error)
+ goto Exit;
/* Allocate memory management structures */
error = create_basic_memory_bitmaps();
@@ -294,7 +301,6 @@
if (error)
goto Finish;
- mutex_lock(&pm_mutex);
if (hibernation_mode == HIBERNATION_TESTPROC) {
printk("swsusp debug: Waiting for 5 seconds.\n");
mdelay(5000);
@@ -316,12 +322,14 @@
swsusp_free();
}
Thaw:
- mutex_unlock(&pm_mutex);
unprepare_processes();
Finish:
free_basic_memory_bitmaps();
Exit:
+ pm_notifier_call_chain(PM_POST_HIBERNATION);
atomic_inc(&snapshot_device_available);
+ Unlock:
+ mutex_unlock(&pm_mutex);
return error;
}
diff --git a/kernel/power/main.c b/kernel/power/main.c
index fc45ed2..4d26ad3 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -23,6 +23,8 @@
#include "power.h"
+BLOCKING_NOTIFIER_HEAD(pm_chain_head);
+
/*This is just an arbitrary number */
#define FREE_PAGE_NUMBER (100)
@@ -78,6 +80,10 @@
if (!pm_ops || !pm_ops->enter)
return -EPERM;
+ error = pm_notifier_call_chain(PM_SUSPEND_PREPARE);
+ if (error)
+ goto Finish;
+
pm_prepare_console();
if (freeze_processes()) {
@@ -125,6 +131,8 @@
Thaw:
thaw_processes();
pm_restore_console();
+ Finish:
+ pm_notifier_call_chain(PM_POST_SUSPEND);
return error;
}
@@ -176,6 +184,7 @@
resume_console();
thaw_processes();
pm_restore_console();
+ pm_notifier_call_chain(PM_POST_SUSPEND);
}
diff --git a/kernel/power/power.h b/kernel/power/power.h
index eab3603..01c2275 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -173,5 +173,15 @@
extern int suspend_enter(suspend_state_t state);
struct timeval;
+/* kernel/power/swsusp.c */
extern void swsusp_show_speed(struct timeval *, struct timeval *,
unsigned int, char *);
+
+/* kernel/power/main.c */
+extern struct blocking_notifier_head pm_chain_head;
+
+static inline int pm_notifier_call_chain(unsigned long val)
+{
+ return (blocking_notifier_call_chain(&pm_chain_head, val, NULL)
+ == NOTIFY_BAD) ? -EINVAL : 0;
+}
diff --git a/kernel/power/user.c b/kernel/power/user.c
index 1f24f30..7f19afe 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -151,10 +151,14 @@
if (data->frozen)
break;
mutex_lock(&pm_mutex);
- if (freeze_processes()) {
- thaw_processes();
- error = -EBUSY;
+ error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
+ if (!error) {
+ error = freeze_processes();
+ if (error)
+ thaw_processes();
}
+ if (error)
+ pm_notifier_call_chain(PM_POST_HIBERNATION);
mutex_unlock(&pm_mutex);
if (!error)
data->frozen = 1;
@@ -165,6 +169,7 @@
break;
mutex_lock(&pm_mutex);
thaw_processes();
+ pm_notifier_call_chain(PM_POST_HIBERNATION);
mutex_unlock(&pm_mutex);
data->frozen = 0;
break;