This is gets the resource limits off a specified process, and is very
similar to prlimit() with a NULL new_rlimit argument. In fact, it tries
that first. However, it then falls back to use /proc/$PID/limits. Why?
Simply because Linux prohibits access to prlimit() for processes with a
different UID, but /proc/$PID/limits still works.
This is preparation to allow nspawn to run unprivileged.
It's pointless showing info that isn#t going to survive the current
invocation, hence hide it.
The "partition number" column is more useful since it kinda shows the
same information, but without the device node name prefixed that is
local to the currentl invocation.
This function is just a wrapper around the BLKGETSIZE64. Which is a
pretty simple ioctl. The only reason to wrap it, is that the headers we
need to call it are a bit messy (as "linux/fs.h" is incompatible with
certain glibc headers). Hence add the simple helper that wraps it and
allows us to do the header mess needed in one file only.
It's also nicely symmetric to blockdev_get_sector_size().
THis brings the list of attributes to delegate to managers of subcgroups
to the state of kernel 6.6.
We probably should unify this list, and maybe generate it automatically
from /sys/kernel/cgroup/delegate, but let's do that another time.
The reference implementation seems to set the 'parameters' field for
method calls to 'null' if nothing is specified on its command line. We
so far only could deal if the parameters field was unset or set to the
empty object. Let's also accept the 'null' type.
It's pulled in by one of the udev rules (63-md-raid-arrays.rules) and it
fails every time, because there's no valid email address in
/etc/mdadm.conf:
[ 5.778153] testsuite-64.sh[403]: mdadm: array /dev/md/mdmirror started.
[ 5.819137] kernel: md/raid1:md127: not clean -- starting background reconstruction
[ 5.819141] kernel: md/raid1:md127: active with 2 out of 2 mirrors
[ 5.819159] kernel: md127: detected capacity change from 0 to 129024
[ 5.821950] kernel: md: resync of RAID array md127
...
[ 5.887192] mdadm[424]: mdadm: No mail address or alert command - not monitoring.
[ 5.890772] systemd[1]: Starting mdmonitor.service...
[ 5.891718] systemd[1]: Started mdmonitor.service.
[ 5.892570] systemd[1]: mdmonitor.service: Main process exited, code=exited, status=1/FAILURE
[ 5.892618] systemd[1]: mdmonitor.service: Failed with result 'exit-code'.
And as we (re)assemble the MD devices multiple times, this gets quite
noisy, especially since we later start hitting the service start rate
limit.
Fedora has the mdmonitor.service patched, so it won't start without
/etc/mdadm.conf being present, but Arch uses the upstream unit which
doesn't have such guard.
Let's just mask the service completely, which replaces all that noise
with one warning:
[ 6.553583] testsuite-64.sh[294]: + udevadm wait --settle ...
[ 6.580700] systemd[1]: sys-devices-virtual-block-md127.device: Failed to enqueue SYSTEMD_WANTS job, ignoring: Unit mdmonitor.service is masked.
The image name is extracted from the image path originally passed in,
i.e. not the contents of the image. And the image UUID is directly
retrieved from the partition table, hence also not from the contents.
Let's hence move the comment to separate out the stuff extract from the
file systems (and thus only available when mounting/with privs/with
block devices) from the data available without any of that.
This is the common case in --user instances, hence handle this
gracefully.
This should be safe since user instances won't get access to
/dev/console-related ttys anyway, but only their own ptys.
