For s390 there is one additional byte associated with each page,
the storage key. This byte contains the referenced and changed
bits and needs to be included into the hibernation image.
If the storage keys are not restored to their previous state all
original pages would appear to be dirty. This can cause
inconsistencies e.g. with read-only filesystems.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Suspend statistics should depend on CONFIG_PM_SLEEP, so make that
happen.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Record S3 failure time about each reason and the latest two failed
devices' names in S3 progress.
We can check it through 'suspend_stats' entry in debugfs.

The motivation of the patch:

We are enabling power features on Medfield. Comparing with PC/notebook,
a mobile enters/exits suspend-2-ram (we call it s3 on Medfield) far
more frequently. If it can't enter suspend-2-ram in time, the power
might be used up soon.

We often find sometimes, a device suspend fails. Then, system retries
s3 over and over again. As display is off, testers and developers
don't know what happens.

Some testers and developers complain they don't know if system
tries suspend-2-ram, and what device fails to suspend. They need
such info for a quick check. The patch adds suspend_stats under
debugfs for users to check suspend to RAM statistics quickly.

If not using this patch, we have other methods to get info about
what device fails. One is to turn on  CONFIG_PM_DEBUG, but users
would get too much info and testers need recompile the system.

In addition, dynamic debug is another good tool to dump debug info.
But it still doesn't match our utilization scenario closely.
1) user need write a user space parser to process the syslog output;
2) Our testing scenario is we leave the mobile for at least hours.
   Then, check its status. No serial console available during the
   testing. One is because console would be suspended, and the other
   is serial console connecting with spi or HSU devices would consume
   power. These devices are powered off at suspend-2-ram.
Signed-off-by: NShuoX Liu <shuox.liu@intel.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Add a global notification chain that gets called upon changes to the
aggregated constraint value for any device.
The notification callbacks are passing the full constraint request data
in order for the callees to have access to it. The current use is for the
platform low-level code to access the target device of the constraint.
Signed-off-by: NJean Pihet <j-pihet@ti.com>
Reviewed-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

In preparation for the per-device constratins support:
 - rename update_target to pm_qos_update_target
 - generalize and export pm_qos_update_target for usage by the upcoming
   per-device latency constraints framework:
   * operate on struct pm_qos_constraints for constraints management,
   * introduce an 'action' parameter for constraints add/update/remove,
   * the return value indicates if the aggregated constraint value has
     changed,
 - update the internal code to operate on struct pm_qos_constraints
 - add a NULL pointer check in the API functions
Signed-off-by: NJean Pihet <j-pihet@ti.com>
Reviewed-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

In preparation for the per-device constratins support, re-organize
the data strctures:
 - add a struct pm_qos_constraints which contains the constraints
 related data
 - update struct pm_qos_object contents to the PM QoS internal object
 data. Add a pointer to struct pm_qos_constraints
 - update the internal code to use the new data structs.
Signed-off-by: NJean Pihet <j-pihet@ti.com>
Reviewed-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Move around the PM QoS misc devices management code
for better readability.
Signed-off-by: NJean Pihet <j-pihet@ti.com>
Acked-by: Nmarkgross <markgross@thegnar.org>
Reviewed-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

 - Misc fixes to improve code readability:
  * rename struct pm_qos_request_list to struct pm_qos_request,
  * rename pm_qos_req parameter to req in internal code,
    consistenly use req in the API parameters,
  * update the in-kernel API callers to the new parameters names,
  * rename of fields names (requests, list, node, constraints)
Signed-off-by: NJean Pihet <j-pihet@ti.com>
Acked-by: Nmarkgross <markgross@thegnar.org>
Reviewed-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

The PM QoS implementation files are better named
kernel/power/qos.c and include/linux/pm_qos.h.

The PM QoS support is compiled under the CONFIG_PM option.
Signed-off-by: NJean Pihet <j-pihet@ti.com>
Acked-by: Nmarkgross <markgross@thegnar.org>
Reviewed-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Function genpd_queue_power_off_work() is not defined for
CONFIG_PM_RUNTIME, so pm_genpd_poweroff_unused() causes a build
error to happen in that case.  Fix the problem by making
pm_genpd_poweroff_unused() depend on CONFIG_PM_RUNTIME too.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

This enables pm_notifier_call_chain() to get the actual error code
in the callback rather than always assume -EINVAL by converting all
PM notifier calls to return encapsulate error code with
notifier_from_errno().
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Some platforms wish to implement their PM core suspend code as
modules.  To do so, these functions need to be exported to modules.

[rjw: Replaced EXPORT_SYMBOL with EXPORT_SYMBOL_GPL]
Reported-by: NJean Pihet <j-pihet@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

A system or a device may need to control suspend/wakeup events. It may
want to wakeup the system after a predefined amount of time or at a
predefined event decided while entering suspend for polling or delayed
work. Then, it may want to enter suspend again if its predefined wakeup
condition is the only wakeup reason and there is no outstanding events;
thus, it does not wakeup the userspace unnecessary or unnecessary
devices and keeps suspended as long as possible (saving the power).

Enabling a system to wakeup after a specified time can be easily
achieved by using RTC. However, to enter suspend again immediately
without invoking userland and unrelated devices, we need additional
features in the suspend framework.

Such need comes from:

 1. Monitoring a critical device status without interrupts that can
wakeup the system. (in-suspend polling)
 An example is ambient temperature monitoring that needs to shut down
the system or a specific device function if it is too hot or cold. The
temperature of a specific device may be needed to be monitored as well;
e.g., a charger monitors battery temperature in order to stop charging
if overheated.

 2. Execute critical "delayed work" at suspend.
 A driver or a system/board may have a delayed work (or any similar
things) that it wants to execute at the requested time.
 For example, some chargers want to check the battery voltage some
time (e.g., 30 seconds) after the battery is fully charged and the
charger has stopped. Then, the charger restarts charging if the voltage
has dropped more than a threshold, which is smaller than "restart-charger"
voltage, which is a threshold to restart charging regardless of the
time passed.

This patch allows to add "suspend_again" callback at struct
platform_suspend_ops and let the "suspend_again" callback return true if
the system is required to enter suspend again after the current instance
of wakeup. Device-wise suspend_again implemented at dev_pm_ops or
syscore is not done because: a) suspend_again feature is usually under
platform-wise decision and controls the behavior of the whole platform
and b) There are very limited devices related to the usage cases of
suspend_again; chargers and temperature sensors are mentioned so far.

With suspend_again callback registered at struct platform_suspend_ops
suspend_ops in kernel/power/suspend.c with suspend_set_ops by the
platform, the suspend framework tries to enter suspend again by
looping suspend_enter() if suspend_again has returned true and there has
been no errors in the suspending sequence or pending wakeups (by
pm_wakeup_pending).

Tested at Exynos4-NURI.

[rjw: Fixed up kerneldoc comment for suspend_enter().]
Signed-off-by: NMyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Signed-off-by: NMichael Witten <mfwitten@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

There is a bug in free_unnecessary_pages() that causes it to
attempt to free too many pages in some cases, which triggers the
BUG_ON() in memory_bm_clear_bit() for copy_bm.  Namely, if
count_data_pages() is initially greater than alloc_normal, we get
to_free_normal equal to 0 and "save" greater from 0.  In that case,
if the sum of "save" and count_highmem_pages() is greater than
alloc_highmem, we subtract a positive number from to_free_normal.
Hence, since to_free_normal was 0 before the subtraction and is
an unsigned int, the result is converted to a huge positive number
that is used as the number of pages to free.

Fix this bug by checking if to_free_normal is actually greater
than or equal to the number we're going to subtract from it.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Reported-and-tested-by: NMatthew Garrett <mjg@redhat.com>
Cc: stable@kernel.org

The common clocks management code in drivers/base/power/clock_ops.c
is going to be used during system-wide power transitions as well as
for runtime PM, so it shouldn't depend on CONFIG_PM_RUNTIME.
However, the suspend/resume functions provided by it for
CONFIG_PM_RUNTIME unset, to be used during system-wide power
transitions, should not behave in the same way as their counterparts
defined for CONFIG_PM_RUNTIME set, because in that case the clocks
are managed differently at run time.

The names of the functions still contain the word "runtime" after
this change, but that is going to be modified by a separate patch
later.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: NKevin Hilman <khilman@ti.com>

Introduce common headers, helper functions and callbacks allowing
platforms to use simple generic power domains for runtime power
management.

Introduce struct generic_pm_domain to be used for representing
power domains that each contain a number of devices and may be
parent domains or subdomains with respect to other power domains.
Among other things, this structure includes callbacks to be
provided by platforms for performing specific tasks related to
power management (i.e. ->stop_device() may disable a device's
clocks, while ->start_device() may enable them, ->power_off() is
supposed to remove power from the entire power domain
and ->power_on() is supposed to restore it).

Introduce functions that can be used as power domain runtime PM
callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(),
as well as helper functions for the initialization of a power
domain represented by a struct generic_power_domain object,
adding a device to or removing a device from it and adding or
removing subdomains.

Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be
selected by the platforms that want to use the new code.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Reviewed-by: NKevin Hilman <khilman@ti.com>

When opening /dev/snapshot device, snapshot_open() creates memory
bitmaps which are freed in snapshot_release(). But if any of the
callbacks called by pm_notifier_call_chain() returns NOTIFY_BAD, open()
fails, snapshot_release() is never called and bitmaps are not freed.
Next attempt to open /dev/snapshot then triggers BUG_ON() check in
create_basic_memory_bitmaps(). This happens e.g. when vmwatchdog module
is active on s390x.
Signed-off-by: NMichal Kubecek <mkubecek@suse.cz>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Cc: stable@kernel.org

Some of the kerneldoc comments in kernel/power/hibernate.c are
outdated and some of them don't adhere to the kernel's standards.
Update them and make them look in a consistent way.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NRandy Dunlap <randy.dunlap@oracle.com>

All architectures supporting hibernation define
arch_prepare_suspend() as an empty function, so remove it.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Some comments in the core hibernate code are outdated, some aren't
necessary any more and at least one of them is plain wrong.  Remove
those comments or update them.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

If device drivers allocate substantial amounts of memory (above 1 MB)
in their hibernate .freeze() callbacks (or in their legacy suspend
callbcks during hibernation), the subsequent creation of hibernate
image may fail due to the lack of memory.  This is the case, because
the drivers' .freeze() callbacks are executed after the hibernate
memory preallocation has been carried out and the preallocated amount
of memory may be too small to cover the new driver allocations.
Unfortunately, the drivers' .prepare() callbacks also are executed
after the hibernate memory preallocation has completed, so they are
not suitable for allocating additional memory either.  Thus the only
way a driver can safely allocate memory during hibernation is to use
a hibernate/suspend notifier.  However, the notifiers are called
before the freezing of user space and the drivers wanting to use them
for allocating additional memory may not know how much memory needs
to be allocated at that point.

To let device drivers overcome this difficulty rework the hibernation
sequence so that the memory preallocation is carried out after the
drivers' .prepare() callbacks have been executed, so that the
.prepare() callbacks can be used for allocating additional memory
to be used by the drivers' .freeze() callbacks.  Update documentation
to match the new behavior of the code.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Now that we have CONFIG_DYNAMIC_DEBUG there is no need for yet
another flag causing dev_dbg() and pr_debug() statements in the
core PM code to produce output.  Moreover, CONFIG_PM_VERBOSE
causes so much output to be generated that it's not really useful
and almost no one sets it.

References: https://bugzilla.kernel.org/show_bug.cgi?id=23182Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

This reverts commit bea3864f
(PM / Hibernate: Reduce autotuned default image size), because users
are now able to resolve the issue this commit was supposed to address
in a different way (i.e. by using the new /sys/power/reserved_size
interface).
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Martin reports that on his system hibernation occasionally fails due
to the lack of memory, because the radeon driver apparently allocates
too much of it during the device freeze stage.  It turns out that the
amount of memory allocated by radeon during hibernation (and
presumably during system suspend too) depends on the utilization of
the GPU (e.g. hibernating while there are two KDE 4 sessions with
compositing enabled causes radeon to allocate more memory than for
one KDE 4 session).

In principle it should be possible to use image_size to make the
memory preallocation mechanism free enough memory for the radeon
driver, but in practice it is not easy to guess the right value
because of the way the preallocation code uses image_size.  For this
reason, it seems reasonable to allow users to control the amount of
memory reserved for driver allocations made after the hibernate
preallocation, which currently is constant and amounts to 1 MB.

Introduce a new sysfs file, /sys/power/reserved_size, whose value
will be used as the amount of memory to reserve for the
post-preallocation reservations made by device drivers, in bytes.
For backwards compatibility, set its default (and initial) value to
the currently used number (1 MB).

References: https://bugzilla.kernel.org/show_bug.cgi?id=34102Reported-and-tested-by: NMartin Steigerwald <Martin@Lichtvoll.de>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

The current implementation of suspend-to-RAM returns 0 if there is an
error from suspend_enter(), because suspend_devices_and_enter() ignores
the return value from suspend_enter().  This patch addresses this issue
and properly keep the error return from suspend_enter() and let
suspend_devices_and_enter relay the error return.
Signed-off-by: NMyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Since suspend, resume and shutdown operations in struct sysdev_class
and struct sysdev_driver are not used any more, remove them.  Also
drop sysdev_suspend(), sysdev_resume() and sysdev_shutdown() used
for executing those operations and modify all of their users
accordingly.  This reduces kernel code size quite a bit and reduces
its complexity.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>

The SNAPSHOT_S2RAM ioctl used for implementing the feature allowing
one to suspend to RAM after creating a hibernation image is currently
broken, because it doesn't clear the "ready" flag in the struct
snapshot_data object handled by it.  As a result, the
SNAPSHOT_UNFREEZE doesn't work correctly after SNAPSHOT_S2RAM has
returned and the user space hibernate task cannot thaw the other
processes as appropriate.  Make SNAPSHOT_S2RAM clear data->ready
to fix this problem.
Tested-by: NAlexandre Felipe Muller de Souza <alexandrefm@mandriva.com.br>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Cc: stable@kernel.org

If the process using the hibernate user space interface closes
/dev/snapshot after creating a hibernation image without thawing
tasks, snapshot_release() should call pm_restore_gfp_mask() to
restore the GFP mask used before the creation of the image.  Make
that happen.
Tested-by: NAlexandre Felipe Muller de Souza <alexandrefm@mandriva.com.br>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Cc: stable@kernel.org

A warning is printed by pm_restrict_gfp_mask() while the
SNAPSHOT_S2RAM ioctl is being executed after creating a hibernation
image, because pm_restrict_gfp_mask() has been called once already
before the image creation and suspend_devices_and_enter() calls it
once again.  This happens after commit 452aa699
(mm/pm: force GFP_NOIO during suspend/hibernation and resume).

To avoid this issue, move pm_restrict_gfp_mask() and
pm_restore_gfp_mask() from suspend_devices_and_enter() to its caller
in kernel/power/suspend.c.
Reported-by: NAlexandre Felipe Muller de Souza <alexandrefm@mandriva.com.br>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Cc: stable@kernel.org

Many different platforms and subsystems may want to disable device
clocks during suspend and enable them during resume which is going to
be done in a very similar way in all those cases.  For this reason,
provide generic routines for the manipulation of device clocks during
suspend and resume.

Convert the ARM shmobile platform to using the new routines.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

If syscore_suspend() fails in suspend_enter(), create_image() or
resume_target_kernel(), it is necessary to call sysdev_resume(),
because sysdev_suspend() has been called already and succeeded
and we are going to abort the transition.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>

Make XEN_SAVE_RESTORE select HIBERNATE_CALLBACKS.
Remove XEN_SAVE_RESTORE dependency from PM_SLEEP.
Signed-off-by: NShriram Rajagopalan <rshriram@cs.ubc.ca>
Acked-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Xen save/restore is going to use hibernate device callbacks for
quiescing devices and putting them back to normal operations and it
would need to select CONFIG_HIBERNATION for this purpose.  However,
that also would cause the hibernate interfaces for user space to be
enabled, which might confuse user space, because the Xen kernels
don't support hibernation.  Moreover, it would be wasteful, as it
would make the Xen kernels include a substantial amount of code that
they would never use.

To address this issue introduce new power management Kconfig option
CONFIG_HIBERNATE_CALLBACKS, such that it will only select the code
that is necessary for the hibernate device callbacks to work and make
CONFIG_HIBERNATION select it.  Then, Xen save/restore will be able to
select CONFIG_HIBERNATE_CALLBACKS without dragging the entire
hibernate code along with it.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Tested-by: NShriram Rajagopalan <rshriram@cs.ubc.ca>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

Replace EXTRA_CFLAGS with ccflags-y.
Signed-off-by: Nmatt mooney <mfm@muteddisk.com>
Acked-by: NWANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

The hibernate image size autotuning mechanism sets the default
image size to 5/2 of the total system RAM, but it is reported
that on some systems device drivers allocate substantial
amounts of memory during suspend and the creation of the image
fails as a result (too little memory is preallocated).

Modify the autotuning mechanism to use 1/3 instead of 2/5 of RAM
as the default image size, which is reported to be sufficient for
the affected systems.

References: https://bugzilla.kernel.org/show_bug.cgi?id=30482Reported-and-tested-by: NMartin Steigerwald <Martin@Lichtvoll.de>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Some subsystems need to carry out suspend/resume and shutdown
operations with one CPU on-line and interrupts disabled.  The only
way to register such operations is to define a sysdev class and
a sysdev specifically for this purpose which is cumbersome and
inefficient.  Moreover, the arguments taken by sysdev suspend,
resume and shutdown callbacks are practically never necessary.

For this reason, introduce a simpler interface allowing subsystems
to register operations to be executed very late during system suspend
and shutdown and very early during resume in the form of
strcut syscore_ops objects.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>

'n' defaults are pretty pointless and actually bogus when used with
prompt-less config options.

The "bool"/"default y" pair with no prompt can be expressed more
compactly using def_bool.

[rjw: Rebased on top of earlier patches modifying this file.]
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

The variable pm_flags is used to prevent APM from being enabled
along with ACPI, which would lead to problems.  However, acpi_init()
is always called before apm_init() and after acpi_init() has
returned, it is known whether or not ACPI will be used.  Namely, if
acpi_disabled is not set after acpi_init() has returned, this means
that ACPI is enabled.  Thus, it is sufficient to check acpi_disabled
in apm_init() to prevent APM from being enabled in parallel with
ACPI.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NLen Brown <len.brown@intel.com>