When suspend-then-hibernate is called, hooks have no ability to determine which
stage of the request is being handled; they only see 'pre' and 'post' with the
verb 'suspend-then-hibernate'. This change introduces an environment variable
called SYSTEMD_SLEEP_ACTION that contains the name of the action that is
processing: 'suspend', 'hibernate', 'hybrid-sleep', or
'suspend-after-failed-hibernate'.
When calculation of swap file offset is unsupported, rely on the
/sys/power/resume & /sys/power/resume_offset values if configured
rather than requiring a matching swap entry to be identified.
Refactor to use dev_t for comparison of resume= device instead of string.
This change checks each swap partition or file reported in /proc/swaps
to see if it matches the values configured with resume= and
resume_offset= kernel parameters. If a match is found, the matching swap
entry is used as the hibernation location regardless of swap priority.
The force field of the Item struct is used to indicate
force creation or appending in different context. This
change renames the field to append_or_force to improve
readability.
In situations where hibernation is requested but resume= and
resume_offset= kernel parameters are not configured, systemd
will attempt to locate a suitable swap location by inspecting
/proc/swaps. This change will use the first suitable swap with
the highest configured priority.
If hibernation is requested but /sys/power/resume and
/sys/power/resume_offset are not configured correctly, systemd-sleep
attempts to calculate swapfile offset using fstat and fiemap.
Btrfs returns virtual device number for stat and a virtual offset
for fiemap which results in incorrect offset calculations. In the
case where offset would be calculated and the user is using Btrfs,
log a debug message and fail to write device and offset values.
Use hibernation configuration as defined in
/sys/power/resume and /sys/power/resume_offset
if present before inspecting /proc/swaps and
attempting to calculate swapfile offset
refactor to use timerfd in place of rtc wakealarm
confirm CLOCK_BOOTTIME_ALARM support in can_s2h
Remove CLOCK_BOOTTIME_ALARM task from TODO
remove unnecessary check on clock_supported return
Zach Smith