linux.git/kernel/power/snapshot.c, branch v2.6.18

[PATCH] swsusp: do not use memcpy for snapshotting memory

2006-07-10T20:24:22+00:00

swsusp should not use memcpy for snapshotting memory, because on some
architectures memcpy may increase preempt_count (i386 does this when
CONFIG_X86_USE_3DNOW is set).  Then, as a result, wrong value of preempt_count
is stored in the image.

Replace memcpy in copy_data_pages with an open-coded loop.

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

Revert "swsusp special saveable pages support" commits

2006-06-26T01:41:00+00:00

This reverts commits

  3e3318dee0878d42ed62a19c292a2ac284135db3 [PATCH] swsusp: x86_64 mark special saveable/unsaveable pages
  b6370d96e09944c6e3ae8d5743ca8a8ab1f79f6c [PATCH] swsusp: i386 mark special saveable/unsaveable pages
  ce4ab0012b32c1a4a1d6e934aeb73bf3151c48d9 [PATCH] swsusp: add architecture special saveable pages support

because not only do they apparently cause page faults on x86, the
infrastructure doesn't compile on powerpc.

Signed-off-by: Linus Torvalds

[PATCH] swsusp: use less memory during resume

2006-06-23T14:43:00+00:00

Make swsusp allocate only as much memory as needed to store the image data
and metadata during resume.

Without this patch swsusp additionally allocates many page frames that will
conflict with the "original" locations of the image data and are considered
as "unsafe", treating them as "eaten" pages (ie.  allocated but unusable).

The patch makes swsusp allocate as many pages as it'll need to store the
data read from the image in one shot, creating a list of allocated "safe"
pages, and use the observation that all pages allocated by it are marked
with the PG_nosave and PG_nosave_free flags set.   Namely, when it's about
to load an image page, swsusp can check whether the page frame
corresponding to the "original" location of this page has been allocated
(ie.  if the page frame has the PG_nosave and PG_nosave_free flags set) and
if so, it can load the page directly into this page frame.   Otherwise it
uses an allocated "safe" page from the list to store the data that will be
copied to their "original" location later on.

This allows us to save many page copyings and page allocations during
resume and in the future it may allow us to load images greater than 50% of
the normal zone.

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

[PATCH] kernel/power/snapshot.c: cleanups

2006-06-23T14:42:59+00:00

- make needlessly global functions static
- make dummy functions static inline

Signed-off-by: Adrian Bunk 
Acked-by: Pavel Machek 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] swsusp: add architecture special saveable pages support

2006-06-23T14:42:59+00:00

1. Add architecture specific pages save/restore support.  Next two patches
   will use this to save/restore 'ACPI NVS' pages.

2. Allow reserved pages 'nosave'.  This could avoid save/restore BIOS
   reserved pages.

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

[PATCH] swsusp: prevent possible image corruption on resume

2006-04-19T16:13:49+00:00

The function free_pagedir() used by swsusp for freeing its internal data
structures clears the PG_nosave and PG_nosave_free flags for each page
being freed.

However, during resume PG_nosave_free set means that the page in
question is "unsafe" (ie.  it will be overwritten in the process of
restoring the saved system state from the image), so it should not be
used for the image data.

Therefore free_pagedir() should not clear PG_nosave_free if it's called
during resume (otherwise "unsafe" pages freed by it may be used for
storing the image data and the data may get corrupted later on).

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

[PATCH] swsusp: drain high mem pages

2006-03-23T15:38:08+00:00

Highmem could be in pcp list as well.

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

[PATCH] suspend: make progress printing prettier

2006-03-23T15:38:08+00:00

Combination of printk/pr_debug led to <7> in the middle of the line, and we
printed way too many dots.

Signed-off-by: Pavel Machek 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] swsusp: userland interface

2006-03-23T15:38:07+00:00

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 
Acked-by: Pavel Machek 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] swsusp: low level interface

2006-03-23T15:38:07+00:00

Introduce the low level interface that can be used for handling the
snapshot of the system memory by the in-kernel swap-writing/reading code of
swsusp and the userland interface code (to be introduced shortly).

Also change the way in which swsusp records the allocated swap pages and,
consequently, simplifies the in-kernel swap-writing/reading code (this is
necessary for the userland interface too).  To this end, it introduces two
helper functions in mm/swapfile.c, so that the swsusp code does not refer
directly to the swap internals.

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