No actual code changes, just splitting out of some dev_t handling
related calls from stat-util.[ch], they are quite a number already, and
deserve their own module now I think.
Also, try to settle on the name "devnum" as the name for the concept,
instead of "devno" or "dev" or "devid". "devnum" is the name exported in
udev APIs, hence probably best to stick to that. (this just renames a
few symbols to "devum", local variables are left untouched, to make the
patch not too invasive)
No actual code changes.
This doesn't change anything for real uses, because we'd initialize the
variable to NULL for _cleanup_ anyway, but let's follow our general pattern
of always setting the output on "success". (Even if that success is an empty
answer here.)
So here's something we should always keep in mind:
systemd-udevd actually does *two* things with BSD file locks on block
devices:
1. While it probes a device it takes a LOCK_SH lock. Thus everyone else
taking a LOCK_EX lock will temporarily block udev from probing
devices, which is good when making changes to it.
2. Whenever a device is closed after write (detected via inotify), udevd
will issue BLKRRPART (requesting the kernel to reread the partition
table). It does this while holding a LOCK_EX lock on the block
device. Thus anyone else taking LOCK_SH or LOCK_EX will temporarily
block udevd from issuing that ioctl. And that's quite relevant, since
the kernel will temporarily flush out all partitions while re-reading
the partition table and then create them anew. Thus it is smart to
take LOCK_SH when dissecting a block device to ensure that no
BLKRRPART is issued in the background, until we mounted the devices.
This revisits the mess around waiting for partition block devices in
the image dissection code. It implements a nice little trick:
Instead of waiting for the kernel to probe the partition table for us
and generate the block devices from it, we'll just do that ourselves.
How can we do it? Via the BLKPG_ADD_PARTITION ioctl, that the kernel has
supported for a while. This ioctl allows creating partition block
devices off "whole" block devices from userspace, without the partitions
necessarily being present in the partition table at all.
So, whenever we want a partition to be there, we'll just issue
BLKPG_ADD_PARTITION. This can either work, in which case we know the
partition is there, and can use it. Yay. Or it can fail with EBUSY,
which the kernel returns if a partition by the selected partition index
already exists (or if an existing partition overlaps with the new one).
But if that's the case, then that's also OK, because the partition will
already exist.
So, regardless if we win or the kernel wins, for us the outcome is the
same: the partition block device will exist after invoking the ioctl.
Yay.
Net effect: we are not dependent on asynchronous uevent messages to wait
for the devices. Instead we synchronously get what we need. This makes
us independent of the (apparently less than reliable) netlink transport,
and should almost always be quicker.
Hopefully addresses #17469 even on older kernels.
Fixes: #17469
%R is already used in service manager specifier expansion (cgroup root),
hence use a different char, that was so far not used.
Follow-up for: 6ceb0a4094
attach_empty() file takes a BSD file lock on the device, and we really
should release that before going to sleep. hence explicitly close the
block device before the sleep instead of relying on _cleanup_ to close
it after the sleep.
This doesn't really make any real difference, given the file should only
contain a single line. But it's conceptually more correct to just remove
the trailing newline/whitespace then the whole lines coming after that.
i.e. if the file actually contains more lines than one, this should
probably be considered an error.
The implementation of MountImageUnit()/systemctl mount-image was
changed to use a /proc/self/fd path as the source, but that causes
the dm-verity files autodiscovery to fail, as it looks for files
in the same directory as the image.
Use the original file path when setting up dm-verity.
That file only exported one function, and it fits nicely within the scope of
"parse helpers". Let's move it there to reduce the file count a bit.
No functional change.
This is a high-level function, and it belongs in libsystemd-shared. This way we
don't end up linking a separate copy into various binaries. It would even end
up in libsystemd, where it is not needed. (Maybe it'd be removed in some
optimization phase, but it's better to not rely on that.)
$ grep -l -r -a 'path is not absolute%s' build/
build/libnss_systemd.so.2
build/pam_systemd_home.so
build/test-dlopen
build/src/basic/libbasic.a.p/path-util.c.o
build/src/basic/libbasic.a
build/src/shared/libsystemd-shared-249.so
build/test-bus-error
build/libnss_mymachines.so.2
build/pam_systemd.so
build/libnss_resolve.so.2
build/libnss_myhostname.so.2
build/libsystemd.so.0.32.0
build/libudev.so.1.7.2
$ grep -l -r -a 'path is not absolute%s' build/
build/src/shared/libsystemd-shared-251.a.p/parse-helpers.c.o
build/src/shared/libsystemd-shared-251.a
build/src/shared/libsystemd-shared-251.so
No functional change.
If the time unit changes after adding the repetition value, the
timer may skip the next elapse. This patch reset sub time units
to minimum value when upper unit is changed.
Fixes#22665.
If we have two or more devices that share the same slot but they are
also multifunction then it is OK to use the slot information even if it
is the same for all of them. Name conflict will be avoided because we
will append function number and form names like, ens1f1, ens1f2...
We must be consistent in the two listings, so let's split out the loading code
and call it from both verb_status() and verb_list(). This effectively makes
verb_status() also call efi_loader_get_entries().
There is still some code duplicated, but that's hard to avoid. Error messages
are made identical for the same errors in various places.
Fixes#22580.
Some parts of our tree used 'Architecture' for storing architectures,
others used ints. Let's unify on the former.
Inspired by #22952's rework of the 'Virtualization' enum.
These days we have a mechanism for safely returning errnos in enum
types, via definining -ERRNO_MAX as one special enu value. Let's use
that for Virtualization.
No change in behaviour, just some typesafety improvement.
The former checks if one UID is inside the uid range set. The latter
checks if a full UID range is inside the uid range set. The former is
hence a special case of the latter.
We would only accept "identical" links, but having e.g. a symlink
/usr/lib/systemd/system/foo-alias.service → /usr/lib/systemd/system/foo.service
when we're trying to create /usr/lib/systemd/system/foo-alias.service →
./foo.service is OK. This fixes an issue found in ubuntuautopkg package
installation, where we'd fail when enabling systemd-resolved.service, because
the existing alias was absolute, and (with the recent patches) we were trying
to create a relative one.
A test is added.
(For .wants/.requires symlinks we were already doing OK. A test is also
added, to verify.)