There is a race between resume from hibernation and the asynchronous
scanning of SCSI devices and to prevent it from happening we need to
call scsi_complete_async_scans() during resume from hibernation.
In addition, if the resume from hibernation is userland-driven, it's
better to wait for all device probes in the kernel to complete before
attempting to open the resume device.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Snapshot device is opened with O_RDONLY during suspend and O_WRONLY durig
resume. Make sure we also call notifiers with correct parameter telling
them what we are really doing.
Signed-off-by: Andrey Borzenkov <arvidjaar@mail.ru>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <gregkh@suse.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We currently use a PM notifier to disable user mode helpers before suspend
and hibernation and to re-enable them during resume. However, this is not
an ideal solution, because if any drivers want to upload firmware into
memory before suspend, they have to use a PM notifier for this purpose and
there is no guarantee that the ordering of PM notifiers will be as
expected (ie. the notifier that disables user mode helpers has to be run
after the driver's notifier used for uploading the firmware).
For this reason, it seems better to move the disabling and enabling of
user mode helpers to separate functions that will be called by the PM core
as necessary.
[akpm@linux-foundation.org: remove unneeded ifdefs]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We can avoid taking the BKL in snapshot_ioctl() if pm_mutex is used to prevent
the ioctls from being executed concurrently.
In addition, although it is only possible to open /dev/snapshot once, the task
which has done that may spawn a child that will inherit the open descriptor,
so in theory they can call snapshot_write(), snapshot_read() and
snapshot_release() concurrently. pm_mutex can also be used for mutual
exclusion in such cases.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
Add PM_RESTORE_PREPARE and PM_POST_RESTORE notifiers to the PM core, to be used
in analogy with the existing PM_HIBERNATION_PREPARE and PM_POST_HIBERNATION
notifiers.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
Three ioctl numbers belonging to the hibernation userland interface,
SNAPSHOT_ATOMIC_SNAPSHOT, SNAPSHOT_AVAIL_SWAP, SNAPSHOT_GET_SWAP_PAGE,
are defined in a wrong way (eg. not portable). Provide new ioctl numbers for
these ioctls and mark the existing ones as deprecated.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
Mark the SNAPSHOT_SET_SWAP_FILE ioctl belonging to the hibernation userland
interface as deprecated.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
Modify the hibernation userland interface by adding two new ioctls to it,
SNAPSHOT_PLATFORM_SUPPORT and SNAPSHOT_POWER_OFF, that can be used,
respectively, to switch the hibernation platform support on/off and to make the
kernel transition the system to the hibernation state (eg. ACPI S4) using the
platform (eg. ACPI) driver.
These ioctls are intended to replace the misdesigned SNAPSHOT_PMOPS ioctl,
which from now is regarded as obsolete and will be removed in the future.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
Add a new ioctl, SNAPSHOT_GET_IMAGE_SIZE, returning the size of the (just
created) hibernation image, to the hibernation userland interface.
This ioctl is necessary so that the userland utilities using the interface need
not access the hibernation image header, owned by the kernel, in order to obtain
the size of the image.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
The syncing of filesystems from within the freezer is generally not needed.
Also, if there's an ext3 filesystem loopback-mounted from a FUSE one, the
syncing results in writes to it and deadlocks. Similarly, it will deadlock if
FUSE implements sync.
Change freeze_processes() so that it doesn't execute sys_sync() and make the
suspend and hibernation code path sync filesystems independently of the
freezer.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <rjw@sisk.pl>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ With Johannes Berg <johannes@sipsolutions.net> ]
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 <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <rjw@sisk.pl>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We forget to increase device_available if there's an error in snapshot_open(),
so the snapshot device cannot be open at all after snapshot_open() has
returned an error.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make swsusp use memory bitmaps instead of page flags for marking 'nosave' and
free pages. This allows us to 'recycle' two page flags that can be used for
other purposes. Also, the memory needed to store the bitmaps is allocated
when necessary (ie. before the suspend) and freed after the resume which is
more reasonable.
The patch is designed to minimize the amount of changes and there are some
nice simplifications and optimizations possible on top of it. I am going to
implement them separately in the future.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit 94985134b7 and
insteads removes the WARN_ON() that caused that commit in the first
place.
The problem is that we call disable_nonboot_cpus() in swsusp before
powering down the system in order to avoid triggering the WARN_ON()
in arch/x86_64/kernel/acpi/sleep.c:init_low_mapping() and this doesn't
work well on Thomas' system.
So instead, remove the WARN_ON() in arch/x86_64/kernel/acpi/sleep.c:
init_low_mapping(), which triggers every time during the suspend to disk
in the platform mode, as the potential problem it is related to doesn't
seem to occur in practice.
[ I think we might want to disallow the case of multiple users of that
mm, or something. Normally, playing with the current process page
tables on the current CPU should be fine as long as we don't have
other threads using those tables at the same time..
Anyway, not pretty, but better than the warning or the lockup - Linus ]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The SNAPSHOT_S2RAM ioctl does not disable the nonboot CPUs before entering
the suspend, although it should do this.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
