[PATCH] swsusp: fix error handling and cleanups

Drop printing during normal boot (when no image exists in swap), print
message when drivers fail, fix error paths and consolidate near-identical
functions in disk.c (and functions with just one statement).

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 22 insertions, 35 deletions

diff --git a/kernel/power/disk.c b/kernel/power/disk.c
index 88beec6dcd11..2d8bf054d036 100644
--- a/kernel/power/disk.c
+++ b/kernel/power/disk.c
@@ -112,24 +112,12 @@ static inline void platform_finish(void)
         }
 }
 
-static void finish(void)
-{
-        device_resume();
-        platform_finish();
-        thaw_processes();
-        enable_nonboot_cpus();
-        pm_restore_console();
-}
-
-
 static int prepare_processes(void)
 {
         int error;
 
         pm_prepare_console();
-
         sys_sync();
-
         disable_nonboot_cpus();
 
         if (freeze_processes()) {
@@ -162,15 +150,6 @@ static void unprepare_processes(void)
         pm_restore_console();
 }
 
-static int prepare_devices(void)
-{
-        int error;
-
-        if ((error = device_suspend(PMSG_FREEZE)))
-                printk("Some devices failed to suspend\n");
-        return error;
-}
-
 /**
  *      pm_suspend_disk - The granpappy of power management.
  *
@@ -187,17 +166,14 @@ int pm_suspend_disk(void)
         error = prepare_processes();
         if (error)
                 return error;
-        error = prepare_devices();
 
+        error = device_suspend(PMSG_FREEZE);
         if (error) {
+                printk("Some devices failed to suspend\n");
                 unprepare_processes();
                 return error;
         }
 
-        pr_debug("PM: Attempting to suspend to disk.\n");
-        if (pm_disk_mode == PM_DISK_FIRMWARE)
-                return pm_ops->enter(PM_SUSPEND_DISK);
-
         pr_debug("PM: snapshotting memory.\n");
         in_suspend = 1;
         if ((error = swsusp_suspend()))
@@ -208,11 +184,20 @@ int pm_suspend_disk(void)
                 error = swsusp_write();
                 if (!error)
                         power_down(pm_disk_mode);
+                else {
+                /* swsusp_write can not fail in device_resume,
+                   no need to do second device_resume */
+                        swsusp_free();
+                        unprepare_processes();
+                        return error;
+                }
         } else
                 pr_debug("PM: Image restored successfully.\n");
+
         swsusp_free();
  Done:
-        finish();
+        device_resume();
+        unprepare_processes();
         return error;
 }
 
@@ -274,15 +259,17 @@ static int software_resume(void)
 
         pr_debug("PM: Preparing devices for restore.\n");
 
-        if ((error = prepare_devices()))
+        if ((error = device_suspend(PMSG_FREEZE))) {
+                printk("Some devices failed to suspend\n");
                 goto Free;
+        }
 
         mb();
 
         pr_debug("PM: Restoring saved image.\n");
         swsusp_resume();
         pr_debug("PM: Restore failed, recovering.n");
-        finish();
+        device_resume();
  Free:
         swsusp_free();
  Cleanup:
diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c
index 1681e8a3fe51..eaacd5cb5889 100644
--- a/kernel/power/swsusp.c
+++ b/kernel/power/swsusp.c
@@ -530,7 +530,6 @@ static int write_pagedir(void)
  *      write_suspend_image - Write entire image and metadata.
  *
  */
-
 static int write_suspend_image(void)
 {
         int error;
@@ -1021,20 +1020,21 @@ int swsusp_suspend(void)
          * at resume time, and evil weirdness ensues.
          */
         if ((error = device_power_down(PMSG_FREEZE))) {
+                printk(KERN_ERR "Some devices failed to power down, aborting suspend\n");
                 local_irq_enable();
                 return error;
         }
 
         if ((error = swsusp_swap_check())) {
-                printk(KERN_ERR "swsusp: FATAL: cannot find swap device, try "
-                                "swapon -a!\n");
+                printk(KERN_ERR "swsusp: cannot find swap device, try swapon -a.\n");
+                device_power_up();
                 local_irq_enable();
                 return error;
         }
 
         save_processor_state();
         if ((error = swsusp_arch_suspend()))
-                printk("Error %d suspending\n", error);
+                printk(KERN_ERR "Error %d suspending\n", error);
         /* Restore control flow magically appears here */
         restore_processor_state();
         BUG_ON (nr_copy_pages_check != nr_copy_pages);
@@ -1314,7 +1314,8 @@ static const char * sanity_check(void)
         if (strcmp(swsusp_info.uts.machine,system_utsname.machine))
                 return "machine";
 #if 0
-        if(swsusp_info.cpus != num_online_cpus())
+        /* We can't use number of online CPUs when we use hotplug to remove them ;-))) */
+        if (swsusp_info.cpus != num_possible_cpus())
                 return "number of cpus";
 #endif
         return NULL;
@@ -1355,7 +1356,6 @@ static int check_sig(void)
                  */
                 error = bio_write_page(0, &swsusp_header);
         } else { 
-                printk(KERN_ERR "swsusp: Suspend partition has wrong signature?\n");
                 return -EINVAL;
         }
         if (!error)