Make swsusp use memory bitmaps to store its internal information during the
resume phase of the suspend-resume cycle.
If the pfns of saveable pages are saved during the suspend phase instead of
the kernel virtual addresses of these pages, we can use them during the resume
phase directly to set the corresponding bits in a memory bitmap. Then, this
bitmap is used to mark the page frames corresponding to the pages that were
saveable before the suspend (aka "unsafe" page frames).
Next, we allocate as many page frames as needed to store the entire suspend
image and make sure that there will be some extra free "safe" page frames for
the list of PBEs constructed later. Subsequently, the image is loaded and, if
possible, the data loaded from it are written into their "original" page
frames (ie. the ones they had occupied before the suspend).
The image data that cannot be written into their "original" page frames are
loaded into "safe" page frames and their "original" kernel virtual addresses,
as well as the addresses of the "safe" pages containing their copies, are
stored in a list of PBEs. Finally, the list of PBEs is used to copy the
remaining image data into their "original" page frames (this is done
atomically, by the architecture-dependent parts of swsusp).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The current suspend code has to be run on one CPU, so we use the CPU
hotplug to take the non-boot CPUs offline on SMP machines. However, we
should also make sure that these CPUs will not be enabled by someone else
after we have disabled them.
The functions disable_nonboot_cpus() and enable_nonboot_cpus() are moved to
kernel/cpu.c, because they now refer to some stuff in there that should
better be static. Also it's better if disable_nonboot_cpus() returns an
error instead of panicking if something goes wrong, and
enable_nonboot_cpus() has no reason to panic(), because the CPUs may have
been enabled by the userland before it tries to take them online.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch is the first of this series that should actually change any
behavior ... by issuing the new event, now tha the rest of the kernel is
prepared to receive it.
This converts the PM core to issue the new PRETHAW message, which the rest of
the kernel is now ready to receive.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add the SNAPSHOT_S2RAM ioctl to the snapshot device.
This ioctl allows a userland application to make the system (previously frozen
with the SNAPSHOT_FREE ioctl) enter the S3 state without freezing processes
and disabling nonboot CPUs for the second time.
This will allow us to implement the suspend-to-disk-and-RAM (STDR)
functionality in the userland suspend tools.
Signed-off-by: Luca Tettamanti <kronos.it@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove the console-switching code from the suspend part of the swsusp userland
interface and let the userland tools switch the console.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Allow swsusp to freeze processes successfully under heavy load by freezing
userspace processes before kernel threads.
[Thanks to Nigel Cunningham <nigel@suspend2.net> for suggesting the
way to go.]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch introduces a user space interface for swsusp.
The interface is based on a special character device, called the snapshot
device, that allows user space processes to perform suspend and resume-related
operations with the help of some ioctls and the read()/write() functions.
Additionally it allows these processes to allocate free swap pages from a
selected swap partition, called the resume partition, so that they know which
sectors of the resume partition are available to them.
The interface uses the same low-level system memory snapshot-handling
functions that are used by the built-it swap-writing/reading code of swsusp.
The interface documentation is included in the patch.
The patch assumes that the major and minor numbers of the snapshot device will
be 10 (ie. misc device) and 231, the registration of which has already been
requested.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Rafael J. Wysocki