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author | Rafael J. Wysocki <rjw@sisk.pl> | 2007-10-26 01:03:33 +0200 |
---|---|---|
committer | Len Brown <len.brown@intel.com> | 2008-02-01 18:30:53 -0500 |
commit | cc5d207c85b9a6fafebe2856ead0a9360978c8cd (patch) | |
tree | 1a7c45b4ffb44a02a76ccd60ec318c796687d568 /Documentation/power/userland-swsusp.txt | |
parent | 96f737490cfc368fdafe49769f52fc8460f9349f (diff) | |
download | talos-obmc-linux-cc5d207c85b9a6fafebe2856ead0a9360978c8cd.tar.gz talos-obmc-linux-cc5d207c85b9a6fafebe2856ead0a9360978c8cd.zip |
Hibernation: Correct definitions of some ioctls (rev. 2)
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>
Diffstat (limited to 'Documentation/power/userland-swsusp.txt')
-rw-r--r-- | Documentation/power/userland-swsusp.txt | 26 |
1 files changed, 13 insertions, 13 deletions
diff --git a/Documentation/power/userland-swsusp.txt b/Documentation/power/userland-swsusp.txt index 0785500e65fb..af52d535a896 100644 --- a/Documentation/power/userland-swsusp.txt +++ b/Documentation/power/userland-swsusp.txt @@ -27,17 +27,17 @@ once at a time. The ioctl() commands recognized by the device are: SNAPSHOT_FREEZE - freeze user space processes (the current process is - not frozen); this is required for SNAPSHOT_ATOMIC_SNAPSHOT + not frozen); this is required for SNAPSHOT_CREATE_IMAGE and SNAPSHOT_ATOMIC_RESTORE to succeed SNAPSHOT_UNFREEZE - thaw user space processes frozen by SNAPSHOT_FREEZE -SNAPSHOT_ATOMIC_SNAPSHOT - create a snapshot of the system memory; the +SNAPSHOT_CREATE_IMAGE - create a snapshot of the system memory; the last argument of ioctl() should be a pointer to an int variable, the value of which will indicate whether the call returned after creating the snapshot (1) or after restoring the system memory state from it (0) (after resume the system finds itself finishing the - SNAPSHOT_ATOMIC_SNAPSHOT ioctl() again); after the snapshot + SNAPSHOT_CREATE_IMAGE ioctl() again); after the snapshot has been created the read() operation can be used to transfer it out of the kernel @@ -49,23 +49,23 @@ SNAPSHOT_ATOMIC_RESTORE - restore the system memory state from the SNAPSHOT_FREE - free memory allocated for the snapshot image -SNAPSHOT_SET_IMAGE_SIZE - set the preferred maximum size of the image +SNAPSHOT_PREF_IMAGE_SIZE - set the preferred maximum size of the image (the kernel will do its best to ensure the image size will not exceed this number, but if it turns out to be impossible, the kernel will create the smallest image possible) SNAPSHOT_GET_IMAGE_SIZE - return the actual size of the hibernation image -SNAPSHOT_AVAIL_SWAP - return the amount of available swap in bytes (the last - argument should be a pointer to an unsigned int variable that will +SNAPSHOT_AVAIL_SWAP_SIZE - return the amount of available swap in bytes (the + last argument should be a pointer to an unsigned int variable that will contain the result if the call is successful). -SNAPSHOT_GET_SWAP_PAGE - allocate a swap page from the resume partition +SNAPSHOT_ALLOC_SWAP_PAGE - allocate a swap page from the resume partition (the last argument should be a pointer to a loff_t variable that will contain the swap page offset if the call is successful) -SNAPSHOT_FREE_SWAP_PAGES - free all swap pages allocated with - SNAPSHOT_GET_SWAP_PAGE +SNAPSHOT_FREE_SWAP_PAGES - free all swap pages allocated by + SNAPSHOT_ALLOC_SWAP_PAGE SNAPSHOT_SET_SWAP_AREA - set the resume partition and the offset (in <PAGE_SIZE> units) from the beginning of the partition at which the swap header is @@ -102,7 +102,7 @@ The device's write() operation is used for uploading the system memory snapshot into the kernel. It has the same limitations as the read() operation. The release() operation frees all memory allocated for the snapshot image -and all swap pages allocated with SNAPSHOT_GET_SWAP_PAGE (if any). +and all swap pages allocated with SNAPSHOT_ALLOC_SWAP_PAGE (if any). Thus it is not necessary to use either SNAPSHOT_FREE or SNAPSHOT_FREE_SWAP_PAGES before closing the device (in fact it will also unfreeze user space processes frozen by SNAPSHOT_UNFREEZE if they are @@ -113,7 +113,7 @@ snapshot image from/to the kernel will use a swap parition, called the resume partition, or a swap file as storage space (if a swap file is used, the resume partition is the partition that holds this file). However, this is not really required, as they can use, for example, a special (blank) suspend partition or -a file on a partition that is unmounted before SNAPSHOT_ATOMIC_SNAPSHOT and +a file on a partition that is unmounted before SNAPSHOT_CREATE_IMAGE and mounted afterwards. These utilities MUST NOT make any assumptions regarding the ordering of @@ -135,7 +135,7 @@ means, such as checksums, to ensure the integrity of the snapshot image. The suspending and resuming utilities MUST lock themselves in memory, preferrably using mlockall(), before calling SNAPSHOT_FREEZE. -The suspending utility MUST check the value stored by SNAPSHOT_ATOMIC_SNAPSHOT +The suspending utility MUST check the value stored by SNAPSHOT_CREATE_IMAGE in the memory location pointed to by the last argument of ioctl() and proceed in accordance with it: 1. If the value is 1 (ie. the system memory snapshot has just been @@ -149,7 +149,7 @@ in accordance with it: image has been saved. (b) The suspending utility SHOULD NOT attempt to perform any file system operations (including reads) on the file systems - that were mounted before SNAPSHOT_ATOMIC_SNAPSHOT has been + that were mounted before SNAPSHOT_CREATE_IMAGE has been called. However, it MAY mount a file system that was not mounted at that time and perform some operations on it (eg. use it for saving the image). |