Merge branch 'acpi-hotplug'

* acpi-hotplug:
  PM / hibernate / memory hotplug: Rework mutual exclusion
  PM / hibernate: Create memory bitmaps after freezing user space
  ACPI / scan: Change ordering of locks for device hotplug

4 files changed, 43 insertions, 45 deletions

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 61d090b6ce25..fbdb82e70d10 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -204,8 +204,6 @@ static int acpi_scan_hot_remove(struct acpi_device *device)
                 return -EINVAL;
         }
 
-        lock_device_hotplug();
-
         /*
          * Carry out two passes here and ignore errors in the first pass,
          * because if the devices in question are memory blocks and
@@ -236,9 +234,6 @@ static int acpi_scan_hot_remove(struct acpi_device *device)
                                             ACPI_UINT32_MAX,
                                             acpi_bus_online_companions, NULL,
                                             NULL, NULL);
-
-                        unlock_device_hotplug();
-
                         put_device(&device->dev);
                         return -EBUSY;
                 }
@@ -249,8 +244,6 @@ static int acpi_scan_hot_remove(struct acpi_device *device)
 
         acpi_bus_trim(device);
 
-        unlock_device_hotplug();
-
         /* Device node has been unregistered. */
         put_device(&device->dev);
         device = NULL;
@@ -289,6 +282,7 @@ static void acpi_bus_device_eject(void *context)
         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
         int error;
 
+        lock_device_hotplug();
         mutex_lock(&acpi_scan_lock);
 
         acpi_bus_get_device(handle, &device);
@@ -312,6 +306,7 @@ static void acpi_bus_device_eject(void *context)
 
  out:
         mutex_unlock(&acpi_scan_lock);
+        unlock_device_hotplug();
         return;
 
  err_out:
@@ -326,8 +321,8 @@ static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source)
         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
         int error;
 
-        mutex_lock(&acpi_scan_lock);
         lock_device_hotplug();
+        mutex_lock(&acpi_scan_lock);
 
         if (ost_source != ACPI_NOTIFY_BUS_CHECK) {
                 acpi_bus_get_device(handle, &device);
@@ -353,9 +348,9 @@ static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source)
                 kobject_uevent(&device->dev.kobj, KOBJ_ONLINE);
 
  out:
-        unlock_device_hotplug();
         acpi_evaluate_hotplug_ost(handle, ost_source, ost_code, NULL);
         mutex_unlock(&acpi_scan_lock);
+        unlock_device_hotplug();
 }
 
 static void acpi_scan_bus_check(void *context)
@@ -446,6 +441,7 @@ void acpi_bus_hot_remove_device(void *context)
         acpi_handle handle = device->handle;
         int error;
 
+        lock_device_hotplug();
         mutex_lock(&acpi_scan_lock);
 
         error = acpi_scan_hot_remove(device);
@@ -455,6 +451,7 @@ void acpi_bus_hot_remove_device(void *context)
                                           NULL);
 
         mutex_unlock(&acpi_scan_lock);
+        unlock_device_hotplug();
         kfree(context);
 }
 EXPORT_SYMBOL(acpi_bus_hot_remove_device);
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index b26f5f1e773e..0b78f72ad39d 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -644,22 +644,23 @@ int hibernate(void)
         if (error)
                 goto Exit;
 
-        /* Allocate memory management structures */
-        error = create_basic_memory_bitmaps();
-        if (error)
-                goto Exit;
-
         printk(KERN_INFO "PM: Syncing filesystems ... ");
         sys_sync();
         printk("done.\n");
 
         error = freeze_processes();
         if (error)
-                goto Free_bitmaps;
+                goto Exit;
+
+        lock_device_hotplug();
+        /* Allocate memory management structures */
+        error = create_basic_memory_bitmaps();
+        if (error)
+                goto Thaw;
 
         error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
         if (error || freezer_test_done)
-                goto Thaw;
+                goto Free_bitmaps;
 
         if (in_suspend) {
                 unsigned int flags = 0;
@@ -682,14 +683,14 @@ int hibernate(void)
                 pr_debug("PM: Image restored successfully.\n");
         }
 
+ Free_bitmaps:
+        free_basic_memory_bitmaps();
  Thaw:
+        unlock_device_hotplug();
         thaw_processes();
 
         /* Don't bother checking whether freezer_test_done is true */
         freezer_test_done = false;
-
- Free_bitmaps:
-        free_basic_memory_bitmaps();
  Exit:
         pm_notifier_call_chain(PM_POST_HIBERNATION);
         pm_restore_console();
@@ -806,21 +807,20 @@ static int software_resume(void)
         pm_prepare_console();
         error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
         if (error)
-                goto close_finish;
-
-        error = create_basic_memory_bitmaps();
-        if (error)
-                goto close_finish;
+                goto Close_Finish;
 
         pr_debug("PM: Preparing processes for restore.\n");
         error = freeze_processes();
-        if (error) {
-                swsusp_close(FMODE_READ);
-                goto Done;
-        }
+        if (error)
+                goto Close_Finish;
 
         pr_debug("PM: Loading hibernation image.\n");
 
+        lock_device_hotplug();
+        error = create_basic_memory_bitmaps();
+        if (error)
+                goto Thaw;
+
         error = swsusp_read(&flags);
         swsusp_close(FMODE_READ);
         if (!error)
@@ -828,9 +828,10 @@ static int software_resume(void)
 
         printk(KERN_ERR "PM: Failed to load hibernation image, recovering.\n");
         swsusp_free();
-        thaw_processes();
- Done:
         free_basic_memory_bitmaps();
+ Thaw:
+        unlock_device_hotplug();
+        thaw_processes();
  Finish:
         pm_notifier_call_chain(PM_POST_RESTORE);
         pm_restore_console();
@@ -840,7 +841,7 @@ static int software_resume(void)
         mutex_unlock(&pm_mutex);
         pr_debug("PM: Hibernation image not present or could not be loaded.\n");
         return error;
-close_finish:
+ Close_Finish:
         swsusp_close(FMODE_READ);
         goto Finish;
 }
diff --git a/kernel/power/user.c b/kernel/power/user.c
index 4ed81e74f86f..72e8f4fd616d 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -60,11 +60,6 @@ static int snapshot_open(struct inode *inode, struct file *filp)
                 error = -ENOSYS;
                 goto Unlock;
         }
-        if(create_basic_memory_bitmaps()) {
-                atomic_inc(&snapshot_device_available);
-                error = -ENOMEM;
-                goto Unlock;
-        }
         nonseekable_open(inode, filp);
         data = &snapshot_state;
         filp->private_data = data;
@@ -90,10 +85,9 @@ static int snapshot_open(struct inode *inode, struct file *filp)
                 if (error)
                         pm_notifier_call_chain(PM_POST_RESTORE);
         }
-        if (error) {
-                free_basic_memory_bitmaps();
+        if (error)
                 atomic_inc(&snapshot_device_available);
-        }
+
         data->frozen = 0;
         data->ready = 0;
         data->platform_support = 0;
@@ -111,11 +105,11 @@ static int snapshot_release(struct inode *inode, struct file *filp)
         lock_system_sleep();
 
         swsusp_free();
-        free_basic_memory_bitmaps();
         data = filp->private_data;
         free_all_swap_pages(data->swap);
         if (data->frozen) {
                 pm_restore_gfp_mask();
+                free_basic_memory_bitmaps();
                 thaw_processes();
         }
         pm_notifier_call_chain(data->mode == O_RDONLY ?
@@ -207,6 +201,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
         if (!mutex_trylock(&pm_mutex))
                 return -EBUSY;
 
+        lock_device_hotplug();
         data = filp->private_data;
 
         switch (cmd) {
@@ -220,14 +215,22 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
                 printk("done.\n");
 
                 error = freeze_processes();
-                if (!error)
+                if (error)
+                        break;
+
+                error = create_basic_memory_bitmaps();
+                if (error)
+                        thaw_processes();
+                else
                         data->frozen = 1;
+
                 break;
 
         case SNAPSHOT_UNFREEZE:
                 if (!data->frozen || data->ready)
                         break;
                 pm_restore_gfp_mask();
+                free_basic_memory_bitmaps();
                 thaw_processes();
                 data->frozen = 0;
                 break;
@@ -371,6 +374,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
 
         }
 
+        unlock_device_hotplug();
         mutex_unlock(&pm_mutex);
 
         return error;
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index ca1dd3aa5eee..53ad1325d7a7 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -51,14 +51,10 @@ DEFINE_MUTEX(mem_hotplug_mutex);
 void lock_memory_hotplug(void)
 {
         mutex_lock(&mem_hotplug_mutex);
-
-        /* for exclusive hibernation if CONFIG_HIBERNATION=y */
-        lock_system_sleep();
 }
 
 void unlock_memory_hotplug(void)
 {
-        unlock_system_sleep();
         mutex_unlock(&mem_hotplug_mutex);
 }