linux-toradex.git/kernel/power/user.c, branch v2.6.23.12

PM: Reduce code duplication between main.c and user.c

2007-07-19T17:04:42+00:00

The SNAPSHOT_S2RAM ioctl code is outdated and it should not duplicate the
suspend code in kernel/power/main.c.  Fix that.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Pavel Machek 
Cc: Nigel Cunningham 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

PM: introduce hibernation and suspend notifiers

2007-07-19T17:04:42+00:00

Make it possible to register hibernation and suspend notifiers, so that
subsystems can perform hibernation-related or suspend-related operations that
should not be carried out by device drivers' .suspend() and .resume()
routines.

[akpm@linux-foundation.org: build fixes]
[akpm@linux-foundation.org: cleanups]
Signed-off-by: Rafael J. Wysocki 
Acked-by: Pavel Machek 
Cc: Nigel Cunningham 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

swsusp: introduce restore platform operations

2007-07-19T17:04:42+00:00

At least on some machines it is necessary to prepare the ACPI firmware for the
restoration of the system memory state from the hibernation image if the
"platform" mode of hibernation has been used.  Namely, in that cases we need
to disable the GPEs before replacing the "boot" kernel with the "frozen"
kernel (cf.  http://bugzilla.kernel.org/show_bug.cgi?id=7887).  After the
restore they will be re-enabled by hibernation_ops->finish(), but if the
restore fails, they have to be re-enabled by the restore code explicitly.

For this purpose we can introduce two additional hibernation operations,
called pre_restore() and restore_cleanup() and call them from the restore code
path.  Still, they should be called if the "platform" mode of hibernation has
been used, so we need to pass the information about the hibernation mode from
the "frozen" kernel to the "boot" kernel in the image header.

Apparently, we can't drop the disabling of GPEs before the restore because of
Bug #7887 .   We also can't do it unconditionally, because the GPEs wouldn't
have been enabled after a successful restore if the suspend had been done in
the 'shutdown' or 'reboot' mode.

In principle we could (and probably should) unconditionally disable the GPEs
before each snapshot creation *and* before the restore, but then we'd have to
unconditionally enable them after the snapshot creation as well as after the
restore (or restore failure)   Still, for this purpose we'd need to modify
acpi_enter_sleep_state_prep() and acpi_leave_sleep_state() and we'd have to
introduce some mechanism synchronizing the disablind/enabling of the GPEs with
the device drivers' .suspend()/.resume() routines and with
disable_/enable_nonboot_cpus().   However, this would have affected the
suspend (ie.  s2ram) code as well as the hibernation, which I'd like to avoid
in this patch series.

Signed-off-by: Rafael J. Wysocki 
Cc: Nigel Cunningham 
Cc: Pavel Machek 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

swsusp: remove code duplication between disk.c and user.c

2007-07-19T17:04:42+00:00

Currently, much of the code in kernel/power/disk.c is duplicated in
kernel/power/user.c , mainly for historical reasons.  By eliminating this code
duplication we can reduce the size of user.c quite substantially and remove
the maintenance difficulty resulting from it.

[bunk@stusta.de: kernel/power/disk.c: make code static]
Signed-off-by: Rafael J. Wysocki 
Acked-by: Pavel Machek 
Cc: Nigel Cunningham 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

swsusp: remove incorrect code from user.c

2007-07-19T17:04:42+00:00

In the face of the recent change of suspend code ordering (cf.
http://marc.info/?l=linux-acpi&m=117938245931603&w=2) we should also modify
the code ordering in swsusp so that hibernation_ops->prepare() is executed
after device_suspend().

However, for this purpose it seems reasonable to eliminate the code
duplication between kernel/power/disk.c and kernel/power/user.c first.  By
eliminating it we can reduce the size of user.c quite substantially and remove
the maintenance difficulty with making essentially the same changes in two
different places.

Moreover, we should also remove the calls to "platform" functions from the
restore code path, since it doesn't carry out any power transition of the
system, but we generally need to disable the GPEs before the restore if the
'platform' hibernation mode has been used.  To do this, we can introduce two
new hibernation_ops to be used in the restore code.

This patch:

Make the code hibernation code in kernel/power/user.c be functionally
equivalent to the corresponding code in kernel/power/disk.c , as it should be.

The calls to the platform functions removed by this patch are incorrect.  They
should be replaced with some other "platform" invocations that will be
introduced in one of the subsequent patches.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Pavel Machek 
Cc: Nigel Cunningham 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

swsusp: Fix userland interface

2007-06-16T20:16:15+00:00

Fix oops caused by 'cat /dev/snapshot', reported by Arkadiusz Miskiewicz,
and make it impossible to thaw tasks with the help of the swsusp userland
interface while there is a snapshot image ready to save.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Pavel Machek 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

PM: Separate hibernation code from suspend code

2007-05-09T19:30:48+00:00

[ With Johannes Berg  ]

Separate the hibernation (aka suspend to disk code) from the other suspend
code.  In particular:

 * Remove the definitions related to hibernation from include/linux/pm.h
 * Introduce struct hibernation_ops and a new hibernate() function to hibernate
   the system, defined in include/linux/suspend.h
 * Separate suspend code in kernel/power/main.c from hibernation-related code
   in kernel/power/disk.c and kernel/power/user.c (with the help of
   hibernation_ops)
 * Switch ACPI (the only user of pm_ops.pm_disk_mode) to hibernation_ops

Signed-off-by: Rafael J. Wysocki 
Cc: Greg KH 
Cc: Pavel Machek 
Cc: Nigel Cunningham 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

swsusp: fix snapshot_release

2007-05-07T19:12:59+00:00

Remove the leftover enable_nonboot_cpus() from snapshot_release().

Signed-off-by: Rafael J. Wysocki 
Cc: Nigel Cunningham 
Cc: Pavel Machek 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

swsusp: use rbtree for tracking allocated swap

2007-05-07T19:12:59+00:00

Make swsusp use extents instead of a bitmap to trace swap pages allocated
for saving the image (the tracking is only needed in case there's an error,
so that the allocated swap pages can be released).

This should allow us to reduce the memory usage, practically always, and
improve performance.

Signed-off-by: Rafael J. Wysocki 
Cc: Nigel Cunningham 
Cc: Pavel Machek 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

swsusp: use GFP_KERNEL for creating basic data structures

2007-05-07T19:12:59+00:00

Make swsusp call create_basic_memory_bitmaps() before processes are frozen, so
that GFP_KERNEL allocations can be made in it.  Additionally, ensure that the
swsusp's userland interface won't be used while either pm_suspend_disk() or
software_resume() is being executed.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Pavel Machek 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds