1 files changed, 191 insertions, 140 deletions

diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 8dc31e02ae12..8f7b1db1ece1 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -23,12 +23,13 @@
 #include <linux/cpu.h>
 #include <linux/freezer.h>
 #include <linux/gfp.h>
+#include <linux/syscore_ops.h>
 #include <scsi/scsi_scan.h>
-#include <asm/suspend.h>
 
 #include "power.h"
 
 
+static int nocompress = 0;
 static int noresume = 0;
 static char resume_file[256] = CONFIG_PM_STD_PARTITION;
 dev_t swsusp_resume_device;
@@ -50,18 +51,17 @@ enum {
 
 static int hibernation_mode = HIBERNATION_SHUTDOWN;
 
-static struct platform_hibernation_ops *hibernation_ops;
+static const struct platform_hibernation_ops *hibernation_ops;
 
 /**
- * hibernation_set_ops - set the global hibernate operations
- * @ops: the hibernation operations to use in subsequent hibernation transitions
+ * hibernation_set_ops - Set the global hibernate operations.
+ * @ops: Hibernation operations to use in subsequent hibernation transitions.
  */
-
-void hibernation_set_ops(struct platform_hibernation_ops *ops)
+void hibernation_set_ops(const struct platform_hibernation_ops *ops)
 {
         if (ops && !(ops->begin && ops->end &&  ops->pre_snapshot
             && ops->prepare && ops->finish && ops->enter && ops->pre_restore
-            && ops->restore_cleanup)) {
+            && ops->restore_cleanup && ops->leave)) {
                 WARN_ON(1);
                 return;
         }
@@ -113,10 +113,9 @@ static int hibernation_test(int level) { return 0; }
 #endif /* !CONFIG_PM_DEBUG */
 
 /**
- *      platform_begin - tell the platform driver that we're starting
- *      hibernation
+ * platform_begin - Call platform to start hibernation.
+ * @platform_mode: Whether or not to use the platform driver.
  */
-
 static int platform_begin(int platform_mode)
 {
         return (platform_mode && hibernation_ops) ?
@@ -124,10 +123,9 @@ static int platform_begin(int platform_mode)
 }
 
 /**
- *      platform_end - tell the platform driver that we've entered the
- *      working state
+ * platform_end - Call platform to finish transition to the working state.
+ * @platform_mode: Whether or not to use the platform driver.
  */
-
 static void platform_end(int platform_mode)
 {
         if (platform_mode && hibernation_ops)
@@ -135,8 +133,11 @@ static void platform_end(int platform_mode)
 }
 
 /**
- *      platform_pre_snapshot - prepare the machine for hibernation using the
- *      platform driver if so configured and return an error code if it fails
+ * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver to prepare the system for creating a hibernate image,
+ * if so configured, and return an error code if that fails.
  */
 
 static int platform_pre_snapshot(int platform_mode)
@@ -146,10 +147,14 @@ static int platform_pre_snapshot(int platform_mode)
 }
 
 /**
- *      platform_leave - prepare the machine for switching to the normal mode
- *      of operation using the platform driver (called with interrupts disabled)
+ * platform_leave - Call platform to prepare a transition to the working state.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver prepare to prepare the machine for switching to the
+ * normal mode of operation.
+ *
+ * This routine is called on one CPU with interrupts disabled.
  */
-
 static void platform_leave(int platform_mode)
 {
         if (platform_mode && hibernation_ops)
@@ -157,10 +162,14 @@ static void platform_leave(int platform_mode)
 }
 
 /**
- *      platform_finish - switch the machine to the normal mode of operation
- *      using the platform driver (must be called after platform_prepare())
+ * platform_finish - Call platform to switch the system to the working state.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver to switch the machine to the normal mode of
+ * operation.
+ *
+ * This routine must be called after platform_prepare().
  */
-
 static void platform_finish(int platform_mode)
 {
         if (platform_mode && hibernation_ops)
@@ -168,11 +177,15 @@ static void platform_finish(int platform_mode)
 }
 
 /**
- *      platform_pre_restore - prepare the platform for the restoration from a
- *      hibernation image.  If the restore fails after this function has been
- *      called, platform_restore_cleanup() must be called.
+ * platform_pre_restore - Prepare for hibernate image restoration.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver to prepare the system for resume from a hibernation
+ * image.
+ *
+ * If the restore fails after this function has been called,
+ * platform_restore_cleanup() must be called.
  */
-
 static int platform_pre_restore(int platform_mode)
 {
         return (platform_mode && hibernation_ops) ?
@@ -180,12 +193,16 @@ static int platform_pre_restore(int platform_mode)
 }
 
 /**
- *      platform_restore_cleanup - switch the platform to the normal mode of
- *      operation after a failing restore.  If platform_pre_restore() has been
- *      called before the failing restore, this function must be called too,
- *      regardless of the result of platform_pre_restore().
+ * platform_restore_cleanup - Switch to the working state after failing restore.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver to switch the system to the normal mode of operation
+ * after a failing restore.
+ *
+ * If platform_pre_restore() has been called before the failing restore, this
+ * function must be called too, regardless of the result of
+ * platform_pre_restore().
  */
-
 static void platform_restore_cleanup(int platform_mode)
 {
         if (platform_mode && hibernation_ops)
@@ -193,10 +210,9 @@ static void platform_restore_cleanup(int platform_mode)
 }
 
 /**
- *      platform_recover - recover the platform from a failure to suspend
- *      devices.
+ * platform_recover - Recover from a failure to suspend devices.
+ * @platform_mode: Whether or not to use the platform driver.
  */
-
 static void platform_recover(int platform_mode)
 {
         if (platform_mode && hibernation_ops && hibernation_ops->recover)
@@ -204,13 +220,12 @@ static void platform_recover(int platform_mode)
 }
 
 /**
- *      swsusp_show_speed - print the time elapsed between two events.
- *      @start: Starting event.
- *      @stop: Final event.
- *      @nr_pages -     number of pages processed between @start and @stop
- *      @msg -          introductory message to print
+ * swsusp_show_speed - Print time elapsed between two events during hibernation.
+ * @start: Starting event.
+ * @stop: Final event.
+ * @nr_pages: Number of memory pages processed between @start and @stop.
+ * @msg: Additional diagnostic message to print.
  */
-
 void swsusp_show_speed(struct timeval *start, struct timeval *stop,
                         unsigned nr_pages, char *msg)
 {
@@ -233,25 +248,18 @@ void swsusp_show_speed(struct timeval *start, struct timeval *stop,
 }
 
 /**
- *      create_image - freeze devices that need to be frozen with interrupts
- *      off, create the hibernation image and thaw those devices.  Control
- *      reappears in this routine after a restore.
+ * create_image - Create a hibernation image.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Execute device drivers' .freeze_noirq() callbacks, create a hibernation image
+ * and execute the drivers' .thaw_noirq() callbacks.
+ *
+ * Control reappears in this routine after the subsequent restore.
  */
-
 static int create_image(int platform_mode)
 {
         int error;
 
-        error = arch_prepare_suspend();
-        if (error)
-                return error;
-
-        /* At this point, dpm_suspend_start() has been called, but *not*
-         * dpm_suspend_noirq(). We *must* call dpm_suspend_noirq() now.
-         * Otherwise, drivers for some devices (e.g. interrupt controllers)
-         * become desynchronized with the actual state of the hardware
-         * at resume time, and evil weirdness ensues.
-         */
         error = dpm_suspend_noirq(PMSG_FREEZE);
         if (error) {
                 printk(KERN_ERR "PM: Some devices failed to power down, "
@@ -270,14 +278,14 @@ static int create_image(int platform_mode)
 
         local_irq_disable();
 
-        error = sysdev_suspend(PMSG_FREEZE);
+        error = syscore_suspend();
         if (error) {
                 printk(KERN_ERR "PM: Some system devices failed to power down, "
                         "aborting hibernation\n");
                 goto Enable_irqs;
         }
 
-        if (hibernation_test(TEST_CORE) || !pm_check_wakeup_events())
+        if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
                 goto Power_up;
 
         in_suspend = 1;
@@ -294,10 +302,7 @@ static int create_image(int platform_mode)
         }
 
  Power_up:
-        sysdev_resume();
-        /* NOTE:  dpm_resume_noirq() is just a resume() for devices
-         * that suspended with irqs off ... no overall powerup.
-         */
+        syscore_resume();
 
  Enable_irqs:
         local_irq_enable();
@@ -315,31 +320,32 @@ static int create_image(int platform_mode)
 }
 
 /**
- *      hibernation_snapshot - quiesce devices and create the hibernation
- *      snapshot image.
- *      @platform_mode - if set, use the platform driver, if available, to
- *                       prepare the platform firmware for the power transition.
+ * hibernation_snapshot - Quiesce devices and create a hibernation image.
+ * @platform_mode: If set, use platform driver to prepare for the transition.
  *
- *      Must be called with pm_mutex held
+ * This routine must be called with pm_mutex held.
  */
-
 int hibernation_snapshot(int platform_mode)
 {
+        pm_message_t msg = PMSG_RECOVER;
         int error;
-        gfp_t saved_mask;
 
         error = platform_begin(platform_mode);
         if (error)
                 goto Close;
 
+        error = dpm_prepare(PMSG_FREEZE);
+        if (error)
+                goto Complete_devices;
+
         /* Preallocate image memory before shutting down devices. */
         error = hibernate_preallocate_memory();
         if (error)
-                goto Close;
+                goto Complete_devices;
 
         suspend_console();
-        saved_mask = clear_gfp_allowed_mask(GFP_IOFS);
-        error = dpm_suspend_start(PMSG_FREEZE);
+        pm_restrict_gfp_mask();
+        error = dpm_suspend(PMSG_FREEZE);
         if (error)
                 goto Recover_platform;
 
@@ -347,17 +353,27 @@ int hibernation_snapshot(int platform_mode)
                 goto Recover_platform;
 
         error = create_image(platform_mode);
-        /* Control returns here after successful restore */
+        /*
+         * Control returns here (1) after the image has been created or the
+         * image creation has failed and (2) after a successful restore.
+         */
 
  Resume_devices:
         /* We may need to release the preallocated image pages here. */
         if (error || !in_suspend)
                 swsusp_free();
 
-        dpm_resume_end(in_suspend ?
-                (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
-        set_gfp_allowed_mask(saved_mask);
+        msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
+        dpm_resume(msg);
+
+        if (error || !in_suspend)
+                pm_restore_gfp_mask();
+
         resume_console();
+
+ Complete_devices:
+        dpm_complete(msg);
+
  Close:
         platform_end(platform_mode);
         return error;
@@ -368,13 +384,14 @@ int hibernation_snapshot(int platform_mode)
 }
 
 /**
- *      resume_target_kernel - prepare devices that need to be suspended with
- *      interrupts off, restore the contents of highmem that have not been
- *      restored yet from the image and run the low level code that will restore
- *      the remaining contents of memory and switch to the just restored target
- *      kernel.
+ * resume_target_kernel - Restore system state from a hibernation image.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Execute device drivers' .freeze_noirq() callbacks, restore the contents of
+ * highmem that have not been restored yet from the image and run the low-level
+ * code that will restore the remaining contents of memory and switch to the
+ * just restored target kernel.
  */
-
 static int resume_target_kernel(bool platform_mode)
 {
         int error;
@@ -396,34 +413,36 @@ static int resume_target_kernel(bool platform_mode)
 
         local_irq_disable();
 
-        error = sysdev_suspend(PMSG_QUIESCE);
+        error = syscore_suspend();
         if (error)
                 goto Enable_irqs;
 
-        /* We'll ignore saved state, but this gets preempt count (etc) right */
         save_processor_state();
         error = restore_highmem();
         if (!error) {
                 error = swsusp_arch_resume();
                 /*
                  * The code below is only ever reached in case of a failure.
-                 * Otherwise execution continues at place where
-                 * swsusp_arch_suspend() was called
+                 * Otherwise, execution continues at the place where
+                 * swsusp_arch_suspend() was called.
                  */
                 BUG_ON(!error);
-                /* This call to restore_highmem() undos the previous one */
+                /*
+                 * This call to restore_highmem() reverts the changes made by
+                 * the previous one.
+                 */
                 restore_highmem();
         }
         /*
          * The only reason why swsusp_arch_resume() can fail is memory being
          * very tight, so we have to free it as soon as we can to avoid
-         * subsequent failures
+         * subsequent failures.
          */
         swsusp_free();
         restore_processor_state();
         touch_softlockup_watchdog();
 
-        sysdev_resume();
+        syscore_resume();
 
  Enable_irqs:
         local_irq_enable();
@@ -440,42 +459,36 @@ static int resume_target_kernel(bool platform_mode)
 }
 
 /**
- *      hibernation_restore - quiesce devices and restore the hibernation
- *      snapshot image.  If successful, control returns in hibernation_snaphot()
- *      @platform_mode - if set, use the platform driver, if available, to
- *                       prepare the platform firmware for the transition.
+ * hibernation_restore - Quiesce devices and restore from a hibernation image.
+ * @platform_mode: If set, use platform driver to prepare for the transition.
  *
- *      Must be called with pm_mutex held
+ * This routine must be called with pm_mutex held.  If it is successful, control
+ * reappears in the restored target kernel in hibernation_snaphot().
  */
-
 int hibernation_restore(int platform_mode)
 {
         int error;
-        gfp_t saved_mask;
 
         pm_prepare_console();
         suspend_console();
-        saved_mask = clear_gfp_allowed_mask(GFP_IOFS);
+        pm_restrict_gfp_mask();
         error = dpm_suspend_start(PMSG_QUIESCE);
         if (!error) {
                 error = resume_target_kernel(platform_mode);
                 dpm_resume_end(PMSG_RECOVER);
         }
-        set_gfp_allowed_mask(saved_mask);
+        pm_restore_gfp_mask();
         resume_console();
         pm_restore_console();
         return error;
 }
 
 /**
- *      hibernation_platform_enter - enter the hibernation state using the
- *      platform driver (if available)
+ * hibernation_platform_enter - Power off the system using the platform driver.
  */
-
 int hibernation_platform_enter(void)
 {
         int error;
-        gfp_t saved_mask;
 
         if (!hibernation_ops)
                 return -ENOSYS;
@@ -491,7 +504,6 @@ int hibernation_platform_enter(void)
 
         entering_platform_hibernation = true;
         suspend_console();
-        saved_mask = clear_gfp_allowed_mask(GFP_IOFS);
         error = dpm_suspend_start(PMSG_HIBERNATE);
         if (error) {
                 if (hibernation_ops->recover)
@@ -512,8 +524,8 @@ int hibernation_platform_enter(void)
                 goto Platform_finish;
 
         local_irq_disable();
-        sysdev_suspend(PMSG_HIBERNATE);
-        if (!pm_check_wakeup_events()) {
+        syscore_suspend();
+        if (pm_wakeup_pending()) {
                 error = -EAGAIN;
                 goto Power_up;
         }
@@ -523,7 +535,7 @@ int hibernation_platform_enter(void)
         while (1);
 
  Power_up:
-        sysdev_resume();
+        syscore_resume();
         local_irq_enable();
         enable_nonboot_cpus();
 
@@ -535,7 +547,6 @@ int hibernation_platform_enter(void)
  Resume_devices:
         entering_platform_hibernation = false;
         dpm_resume_end(PMSG_RESTORE);
-        set_gfp_allowed_mask(saved_mask);
         resume_console();
 
  Close:
@@ -545,12 +556,12 @@ int hibernation_platform_enter(void)
 }
 
 /**
- *      power_down - Shut the machine down for hibernation.
+ * power_down - Shut the machine down for hibernation.
  *
- *      Use the platform driver, if configured so; otherwise try
- *      to power off or reboot.
+ * Use the platform driver, if configured, to put the system into the sleep
+ * state corresponding to hibernation, or try to power it off or reboot,
+ * depending on the value of hibernation_mode.
  */
-
 static void power_down(void)
 {
         switch (hibernation_mode) {
@@ -587,9 +598,8 @@ static int prepare_processes(void)
 }
 
 /**
- *      hibernate - The granpappy of the built-in hibernation management
+ * hibernate - Carry out system hibernation, including saving the image.
  */
-
 int hibernate(void)
 {
         int error;
@@ -638,11 +648,15 @@ int hibernate(void)
 
                 if (hibernation_mode == HIBERNATION_PLATFORM)
                         flags |= SF_PLATFORM_MODE;
+                if (nocompress)
+                        flags |= SF_NOCOMPRESS_MODE;
                 pr_debug("PM: writing image.\n");
                 error = swsusp_write(flags);
                 swsusp_free();
                 if (!error)
                         power_down();
+                in_suspend = 0;
+                pm_restore_gfp_mask();
         } else {
                 pr_debug("PM: Image restored successfully.\n");
         }
@@ -663,17 +677,20 @@ int hibernate(void)
 
 
 /**
- *      software_resume - Resume from a saved image.
+ * software_resume - Resume from a saved hibernation image.
+ *
+ * This routine is called as a late initcall, when all devices have been
+ * discovered and initialized already.
  *
- *      Called as a late_initcall (so all devices are discovered and
- *      initialized), we call swsusp to see if we have a saved image or not.
- *      If so, we quiesce devices, the restore the saved image. We will
- *      return above (in hibernate() ) if everything goes well.
- *      Otherwise, we fail gracefully and return to the normally
- *      scheduled program.
+ * The image reading code is called to see if there is a hibernation image
+ * available for reading.  If that is the case, devices are quiesced and the
+ * contents of memory is restored from the saved image.
  *
+ * If this is successful, control reappears in the restored target kernel in
+ * hibernation_snaphot() which returns to hibernate().  Otherwise, the routine
+ * attempts to recover gracefully and make the kernel return to the normal mode
+ * of operation.
  */
-
 static int software_resume(void)
 {
         int error;
@@ -705,7 +722,7 @@ static int software_resume(void)
                 goto Unlock;
         }
 
-        pr_debug("PM: Checking image partition %s\n", resume_file);
+        pr_debug("PM: Checking hibernation image partition %s\n", resume_file);
 
         /* Check if the device is there */
         swsusp_resume_device = name_to_dev_t(resume_file);
@@ -730,10 +747,10 @@ static int software_resume(void)
         }
 
  Check_image:
-        pr_debug("PM: Resume from partition %d:%d\n",
+        pr_debug("PM: Hibernation image partition %d:%d present\n",
                 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
 
-        pr_debug("PM: Checking hibernation image.\n");
+        pr_debug("PM: Looking for hibernation image.\n");
         error = swsusp_check();
         if (error)
                 goto Unlock;
@@ -765,14 +782,14 @@ static int software_resume(void)
                 goto Done;
         }
 
-        pr_debug("PM: Reading hibernation image.\n");
+        pr_debug("PM: Loading hibernation image.\n");
 
         error = swsusp_read(&flags);
         swsusp_close(FMODE_READ);
         if (!error)
                 hibernation_restore(flags & SF_PLATFORM_MODE);
 
-        printk(KERN_ERR "PM: Restore failed, recovering.\n");
+        printk(KERN_ERR "PM: Failed to load hibernation image, recovering.\n");
         swsusp_free();
         thaw_processes();
  Done:
@@ -785,7 +802,7 @@ static int software_resume(void)
         /* For success case, the suspend path will release the lock */
  Unlock:
         mutex_unlock(&pm_mutex);
-        pr_debug("PM: Resume from disk failed.\n");
+        pr_debug("PM: Hibernation image not present or could not be loaded.\n");
         return error;
 close_finish:
         swsusp_close(FMODE_READ);
@@ -803,21 +820,17 @@ static const char * const hibernation_modes[] = {
         [HIBERNATION_TESTPROC]  = "testproc",
 };
 
-/**
- *      disk - Control hibernation mode
- *
- *      Suspend-to-disk can be handled in several ways. We have a few options
- *      for putting the system to sleep - using the platform driver (e.g. ACPI
- *      or other hibernation_ops), powering off the system or rebooting the
- *      system (for testing) as well as the two test modes.
+/*
+ * /sys/power/disk - Control hibernation mode.
  *
- *      The system can support 'platform', and that is known a priori (and
- *      encoded by the presence of hibernation_ops). However, the user may
- *      choose 'shutdown' or 'reboot' as alternatives, as well as one fo the
- *      test modes, 'test' or 'testproc'.
+ * Hibernation can be handled in several ways.  There are a few different ways
+ * to put the system into the sleep state: using the platform driver (e.g. ACPI
+ * or other hibernation_ops), powering it off or rebooting it (for testing
+ * mostly), or using one of the two available test modes.
  *
- *      show() will display what the mode is currently set to.
- *      store() will accept one of
+ * The sysfs file /sys/power/disk provides an interface for selecting the
+ * hibernation mode to use.  Reading from this file causes the available modes
+ * to be printed.  There are 5 modes that can be supported:
  *
  *      'platform'
  *      'shutdown'
@@ -825,8 +838,14 @@ static const char * const hibernation_modes[] = {
  *      'test'
  *      'testproc'
  *
- *      It will only change to 'platform' if the system
- *      supports it (as determined by having hibernation_ops).
+ * If a platform hibernation driver is in use, 'platform' will be supported
+ * and will be used by default.  Otherwise, 'shutdown' will be used by default.
+ * The selected option (i.e. the one corresponding to the current value of
+ * hibernation_mode) is enclosed by a square bracket.
+ *
+ * To select a given hibernation mode it is necessary to write the mode's
+ * string representation (as returned by reading from /sys/power/disk) back
+ * into /sys/power/disk.
  */
 
 static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
@@ -859,7 +878,6 @@ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
         return buf-start;
 }
 
-
 static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
                           const char *buf, size_t n)
 {
@@ -961,10 +979,33 @@ static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *att
 
 power_attr(image_size);
 
+static ssize_t reserved_size_show(struct kobject *kobj,
+                                  struct kobj_attribute *attr, char *buf)
+{
+        return sprintf(buf, "%lu\n", reserved_size);
+}
+
+static ssize_t reserved_size_store(struct kobject *kobj,
+                                   struct kobj_attribute *attr,
+                                   const char *buf, size_t n)
+{
+        unsigned long size;
+
+        if (sscanf(buf, "%lu", &size) == 1) {
+                reserved_size = size;
+                return n;
+        }
+
+        return -EINVAL;
+}
+
+power_attr(reserved_size);
+
 static struct attribute * g[] = {
         &disk_attr.attr,
         &resume_attr.attr,
         &image_size_attr.attr,
+        &reserved_size_attr.attr,
         NULL,
 };
 
@@ -1004,6 +1045,15 @@ static int __init resume_offset_setup(char *str)
         return 1;
 }
 
+static int __init hibernate_setup(char *str)
+{
+        if (!strncmp(str, "noresume", 8))
+                noresume = 1;
+        else if (!strncmp(str, "nocompress", 10))
+                nocompress = 1;
+        return 1;
+}
+
 static int __init noresume_setup(char *str)
 {
         noresume = 1;
@@ -1013,3 +1063,4 @@ static int __init noresume_setup(char *str)
 __setup("noresume", noresume_setup);
 __setup("resume_offset=", resume_offset_setup);
 __setup("resume=", resume_setup);
+__setup("hibernate=", hibernate_setup);