7 files changed, 27 insertions, 23 deletions

diff --git a/kernel/freezer.c b/kernel/freezer.c
index 6f56a9e219fa..b162b74611e4 100644
--- a/kernel/freezer.c
+++ b/kernel/freezer.c
@@ -15,7 +15,9 @@
 atomic_t system_freezing_cnt = ATOMIC_INIT(0);
 EXPORT_SYMBOL(system_freezing_cnt);
 
-/* indicate whether PM freezing is in effect, protected by pm_mutex */
+/* indicate whether PM freezing is in effect, protected by
+ * system_transition_mutex
+ */
 bool pm_freezing;
 bool pm_nosig_freezing;
 
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 9c85c7822383..abef759de7c8 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -338,7 +338,7 @@ static int create_image(int platform_mode)
  * hibernation_snapshot - Quiesce devices and create a hibernation image.
  * @platform_mode: If set, use platform driver to prepare for the transition.
  *
- * This routine must be called with pm_mutex held.
+ * This routine must be called with system_transition_mutex held.
  */
 int hibernation_snapshot(int platform_mode)
 {
@@ -500,8 +500,9 @@ static int resume_target_kernel(bool platform_mode)
  * hibernation_restore - Quiesce devices and restore from a hibernation image.
  * @platform_mode: If set, use platform driver to prepare for the transition.
  *
- * This routine must be called with pm_mutex held.  If it is successful, control
- * reappears in the restored target kernel in hibernation_snapshot().
+ * This routine must be called with system_transition_mutex held.  If it is
+ * successful, control reappears in the restored target kernel in
+ * hibernation_snapshot().
  */
 int hibernation_restore(int platform_mode)
 {
@@ -638,6 +639,7 @@ static void power_down(void)
                 break;
         case HIBERNATION_PLATFORM:
                 hibernation_platform_enter();
+                /* Fall through */
         case HIBERNATION_SHUTDOWN:
                 if (pm_power_off)
                         kernel_power_off();
@@ -805,13 +807,13 @@ static int software_resume(void)
          * 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
+         * calling hibernate functions (which take system_transition_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);
+        mutex_lock_nested(&system_transition_mutex, SINGLE_DEPTH_NESTING);
 
         if (swsusp_resume_device)
                 goto Check_image;
@@ -899,7 +901,7 @@ static int software_resume(void)
         atomic_inc(&snapshot_device_available);
         /* For success case, the suspend path will release the lock */
  Unlock:
-        mutex_unlock(&pm_mutex);
+        mutex_unlock(&system_transition_mutex);
         pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
         return error;
  Close_Finish:
diff --git a/kernel/power/main.c b/kernel/power/main.c
index d9706da10930..35b50823d83b 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -15,17 +15,16 @@
 #include <linux/workqueue.h>
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
+#include <linux/suspend.h>
 
 #include "power.h"
 
-DEFINE_MUTEX(pm_mutex);
-
 #ifdef CONFIG_PM_SLEEP
 
 void lock_system_sleep(void)
 {
         current->flags |= PF_FREEZER_SKIP;
-        mutex_lock(&pm_mutex);
+        mutex_lock(&system_transition_mutex);
 }
 EXPORT_SYMBOL_GPL(lock_system_sleep);
 
@@ -37,8 +36,9 @@ void unlock_system_sleep(void)
          *
          * Reason:
          * Fundamentally, we just don't need it, because freezing condition
-         * doesn't come into effect until we release the pm_mutex lock,
-         * since the freezer always works with pm_mutex held.
+         * doesn't come into effect until we release the
+         * system_transition_mutex lock, since the freezer always works with
+         * system_transition_mutex held.
          *
          * More importantly, in the case of hibernation,
          * unlock_system_sleep() gets called in snapshot_read() and
@@ -47,7 +47,7 @@ void unlock_system_sleep(void)
          * enter the refrigerator, thus causing hibernation to lockup.
          */
         current->flags &= ~PF_FREEZER_SKIP;
-        mutex_unlock(&pm_mutex);
+        mutex_unlock(&system_transition_mutex);
 }
 EXPORT_SYMBOL_GPL(unlock_system_sleep);
 
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 87331565e505..9e13afe65a14 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -556,7 +556,7 @@ static int enter_state(suspend_state_t state)
         } else if (!valid_state(state)) {
                 return -EINVAL;
         }
-        if (!mutex_trylock(&pm_mutex))
+        if (!mutex_trylock(&system_transition_mutex))
                 return -EBUSY;
 
         if (state == PM_SUSPEND_TO_IDLE)
@@ -590,7 +590,7 @@ static int enter_state(suspend_state_t state)
         pm_pr_dbg("Finishing wakeup.\n");
         suspend_finish();
  Unlock:
-        mutex_unlock(&pm_mutex);
+        mutex_unlock(&system_transition_mutex);
         return error;
 }
 
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index c2bcf97d24c8..d7f6c1a288d3 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -923,7 +923,7 @@ int swsusp_write(unsigned int flags)
         }
         memset(&snapshot, 0, sizeof(struct snapshot_handle));
         error = snapshot_read_next(&snapshot);
-        if (error < PAGE_SIZE) {
+        if (error < (int)PAGE_SIZE) {
                 if (error >= 0)
                         error = -EFAULT;
 
@@ -1483,7 +1483,7 @@ int swsusp_read(unsigned int *flags_p)
 
         memset(&snapshot, 0, sizeof(struct snapshot_handle));
         error = snapshot_write_next(&snapshot);
-        if (error < PAGE_SIZE)
+        if (error < (int)PAGE_SIZE)
                 return error < 0 ? error : -EFAULT;
         header = (struct swsusp_info *)data_of(snapshot);
         error = get_swap_reader(&handle, flags_p);
diff --git a/kernel/power/user.c b/kernel/power/user.c
index abd225550271..2d8b60a3c86b 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -216,7 +216,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
         if (!capable(CAP_SYS_ADMIN))
                 return -EPERM;
 
-        if (!mutex_trylock(&pm_mutex))
+        if (!mutex_trylock(&system_transition_mutex))
                 return -EBUSY;
 
         lock_device_hotplug();
@@ -394,7 +394,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
         }
 
         unlock_device_hotplug();
-        mutex_unlock(&pm_mutex);
+        mutex_unlock(&system_transition_mutex);
 
         return error;
 }
diff --git a/kernel/reboot.c b/kernel/reboot.c
index e4ced883d8de..8fb44dec9ad7 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -294,7 +294,7 @@ void kernel_power_off(void)
 }
 EXPORT_SYMBOL_GPL(kernel_power_off);
 
-static DEFINE_MUTEX(reboot_mutex);
+DEFINE_MUTEX(system_transition_mutex);
 
 /*
  * Reboot system call: for obvious reasons only root may call it,
@@ -338,7 +338,7 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
         if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off)
                 cmd = LINUX_REBOOT_CMD_HALT;
 
-        mutex_lock(&reboot_mutex);
+        mutex_lock(&system_transition_mutex);
         switch (cmd) {
         case LINUX_REBOOT_CMD_RESTART:
                 kernel_restart(NULL);
@@ -389,7 +389,7 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
                 ret = -EINVAL;
                 break;
         }
-        mutex_unlock(&reboot_mutex);
+        mutex_unlock(&system_transition_mutex);
         return ret;
 }