diff options
| author | Mario Limonciello <mario.limonciello@dell.com> | 2018-03-28 12:01:09 -0500 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2018-03-30 12:01:20 +0200 |
| commit | 355064675f1c997cea017ea64c8f2c216e5425d9 (patch) | |
| tree | 71dcf9924f7878f793cb72f21f69fad606523b1f | |
| parent | dbdd0f58fd2cdde5cf945c9da67a2d52d32ba550 (diff) | |
| download | linux-355064675f1c997cea017ea64c8f2c216e5425d9.tar.bz2 | |
PM / hibernate: Make passing hibernate offsets more friendly
Currently the only way to specify a hibernate offset for a
swap file is on the kernel command line.
Add a new /sys/power/resume_offset that lets userspace
specify the offset and disk to use when initiating a hibernate
cycle.
Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| -rw-r--r-- | Documentation/ABI/testing/sysfs-power | 14 | ||||
| -rw-r--r-- | Documentation/power/swsusp.txt | 10 | ||||
| -rw-r--r-- | kernel/power/hibernate.c | 24 |
3 files changed, 47 insertions, 1 deletions
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power index 1e0d1dac706b..2f813d644c69 100644 --- a/Documentation/ABI/testing/sysfs-power +++ b/Documentation/ABI/testing/sysfs-power @@ -287,3 +287,17 @@ Description: Writing a "1" to this file enables the debug messages and writing a "0" (default) to it disables them. Reads from this file return the current value. + +What: /sys/power/resume_offset +Date: April 2018 +Contact: Mario Limonciello <mario.limonciello@dell.com> +Description: + This file is used for telling the kernel an offset into a disk + to use when hibernating the system such as with a swap file. + + Reads from this file will display the current offset + the kernel will be using on the next hibernation + attempt. + + Using this sysfs file will override any values that were + set using the kernel command line for disk offset.
\ No newline at end of file diff --git a/Documentation/power/swsusp.txt b/Documentation/power/swsusp.txt index 9f2f942a01cf..cc87adf44c0a 100644 --- a/Documentation/power/swsusp.txt +++ b/Documentation/power/swsusp.txt @@ -24,8 +24,16 @@ Some warnings, first. * see the FAQ below for details. (This is not true for more traditional * power states like "standby", which normally don't turn USB off.) +Swap partition: You need to append resume=/dev/your_swap_partition to kernel command -line. Then you suspend by +line or specify it using /sys/power/resume. + +Swap file: +If using a swapfile you can also specify a resume offset using +resume_offset=<number> on the kernel command line or specify it +in /sys/power/resume_offset. + +After preparing then you suspend by echo shutdown > /sys/power/disk; echo disk > /sys/power/state diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index a5c36e9c56a6..d58fad3db22d 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -1061,6 +1061,29 @@ static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr, power_attr(resume); +static ssize_t resume_offset_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%llu\n", (unsigned long long)swsusp_resume_block); +} + +static ssize_t resume_offset_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, + size_t n) +{ + unsigned long long offset; + int rc; + + rc = kstrtoull(buf, 0, &offset); + if (rc) + return rc; + swsusp_resume_block = offset; + + return n; +} + +power_attr(resume_offset); + static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { @@ -1106,6 +1129,7 @@ power_attr(reserved_size); static struct attribute * g[] = { &disk_attr.attr, + &resume_offset_attr.attr, &resume_attr.attr, &image_size_attr.attr, &reserved_size_attr.attr, |