2 files changed, 16 insertions, 0 deletions

diff --git a/Documentation/power/interface.txt b/Documentation/power/interface.txt
index f5ebda5f4276..bd4ffb5bd49a 100644
--- a/Documentation/power/interface.txt
+++ b/Documentation/power/interface.txt
@@ -41,3 +41,14 @@ to. Writing to this file will accept one of
 It will only change to 'firmware' or 'platform' if the system supports
 it. 
 
+/sys/power/image_size controls the size of the image created by
+the suspend-to-disk mechanism.  It can be written a string
+representing a non-negative integer that will be used as an upper
+limit of the image size, in megabytes.  The suspend-to-disk mechanism will
+do its best to ensure the image size will not exceed that number.  However,
+if this turns out to be impossible, it will try to suspend anyway using the
+smallest image possible.  In particular, if "0" is written to this file, the
+suspend image will be as small as possible.
+
+Reading from this file will display the current image size limit, which
+is set to 500 MB by default.
diff --git a/Documentation/power/swsusp.txt b/Documentation/power/swsusp.txt
index b0d50840788e..cd0fcd89a6f0 100644
--- a/Documentation/power/swsusp.txt
+++ b/Documentation/power/swsusp.txt
@@ -27,6 +27,11 @@ echo shutdown > /sys/power/disk; echo disk > /sys/power/state
 
 echo platform > /sys/power/disk; echo disk > /sys/power/state
 
+If you want to limit the suspend image size to N megabytes, do
+
+echo N > /sys/power/image_size
+
+before suspend (it is limited to 500 MB by default).
 
 Encrypted suspend image:
 ------------------------