From ecbd0da1eced957e0cbb611b4a4cb5b0cf63ba31 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 6 Dec 2006 20:34:13 -0800 Subject: [PATCH] swsusp: document support for swap files Document the "resume_offset=" command line parameter as well as the way in which swap files are supported by swsusp. Signed-off-by: Rafael J. Wysocki Cc: Pavel Machek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/power/swsusp.txt | 18 +++++------------- 1 file changed, 5 insertions(+), 13 deletions(-) (limited to 'Documentation/power/swsusp.txt') diff --git a/Documentation/power/swsusp.txt b/Documentation/power/swsusp.txt index e635e6f1e316..0761ff6c57ed 100644 --- a/Documentation/power/swsusp.txt +++ b/Documentation/power/swsusp.txt @@ -297,20 +297,12 @@ system is shut down or suspended. Additionally use the encrypted suspend image to prevent sensitive data from being stolen after resume. -Q: Why can't we suspend to a swap file? +Q: Can I suspend to a swap file? -A: Because accessing swap file needs the filesystem mounted, and -filesystem might do something wrong (like replaying the journal) -during mount. - -There are few ways to get that fixed: - -1) Probably could be solved by modifying every filesystem to support -some kind of "really read-only!" option. Patches welcome. - -2) suspend2 gets around that by storing absolute positions in on-disk -image (and blocksize), with resume parameter pointing directly to -suspend header. +A: Generally, yes, you can. However, it requires you to use the "resume=" and +"resume_offset=" kernel command line parameters, so the resume from a swap file +cannot be initiated from an initrd or initramfs image. See +swsusp-and-swap-files.txt for details. Q: Is there a maximum system RAM size that is supported by swsusp? -- cgit