Hibernation: Add PM_RESTORE_PREPARE and PM_POST_RESTORE notifiers (rev. 2)

[mv-sheeva.git] / kernel / power / disk.c

diff --git a/kernel/power/disk.c b/kernel/power/disk.c
index 8b15f777010a9daefe2361adfbf5c1c0851dfb75..6597365082393718923b7fb861c1210c714b7bf1 100644 (file)
--- a/kernel/power/disk.c
+++ b/kernel/power/disk.c
@@ -456,7 +456,17 @@ static int software_resume(void)
        int error;
        unsigned int flags;
 
-       mutex_lock(&pm_mutex);
+       /*
+        * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
+        * is configured into the kernel. Since the regular hibernate
+        * trigger path is via sysfs which takes a buffer mutex before
+        * calling hibernate functions (which take pm_mutex) this can
+        * cause lockdep to complain about a possible ABBA deadlock
+        * which cannot happen since we're in the boot code here and
+        * sysfs can't be invoked yet. Therefore, we use a subclass
+        * here to avoid lockdep complaining.
+        */
+       mutex_lock_nested(&pm_mutex, SINGLE_DEPTH_NESTING);
        if (!swsusp_resume_device) {
                if (!strlen(resume_file)) {
                        mutex_unlock(&pm_mutex);
@@ -489,6 +499,10 @@ static int software_resume(void)
                goto Unlock;
        }
 
+       error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
+       if (error)
+               goto Finish;
+
        error = create_basic_memory_bitmaps();
        if (error)
                goto Finish;
@@ -512,6 +526,7 @@ static int software_resume(void)
  Done:
        free_basic_memory_bitmaps();
  Finish:
+       pm_notifier_call_chain(PM_POST_RESTORE);
        atomic_inc(&snapshot_device_available);
        /* For success case, the suspend path will release the lock */
  Unlock:
@@ -557,7 +572,8 @@ static const char * const hibernation_modes[] = {
  *     supports it (as determined by having hibernation_ops).
  */
 
-static ssize_t disk_show(struct kset *kset, char *buf)
+static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
+                        char *buf)
 {
        int i;
        char *start = buf;
@@ -587,7 +603,8 @@ static ssize_t disk_show(struct kset *kset, char *buf)
 }
 
 
-static ssize_t disk_store(struct kset *kset, const char *buf, size_t n)
+static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
+                         const char *buf, size_t n)
 {
        int error = 0;
        int i;
@@ -632,13 +649,15 @@ static ssize_t disk_store(struct kset *kset, const char *buf, size_t n)
 
 power_attr(disk);
 
-static ssize_t resume_show(struct kset *kset, char *buf)
+static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
+                          char *buf)
 {
        return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
                       MINOR(swsusp_resume_device));
 }
 
-static ssize_t resume_store(struct kset *kset, const char *buf, size_t n)
+static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
+                           const char *buf, size_t n)
 {
        unsigned int maj, min;
        dev_t res;
@@ -664,12 +683,14 @@ static ssize_t resume_store(struct kset *kset, const char *buf, size_t n)
 
 power_attr(resume);
 
-static ssize_t image_size_show(struct kset *kset, char *buf)
+static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
+                              char *buf)
 {
        return sprintf(buf, "%lu\n", image_size);
 }
 
-static ssize_t image_size_store(struct kset *kset, const char *buf, size_t n)
+static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
+                               const char *buf, size_t n)
 {
        unsigned long size;
 
@@ -698,7 +719,7 @@ static struct attribute_group attr_group = {
 
 static int __init pm_disk_init(void)
 {
-       return sysfs_create_group(&power_subsys.kobj, &attr_group);
+       return sysfs_create_group(power_kobj, &attr_group);
 }
 
 core_initcall(pm_disk_init);