https://bugzilla.redhat.com/show_bug.cgi?id=1640465
Weirdly enough, there can be symlinks in the path we are trying
to fix. If it is the case our clever algorithm that finds matches
against mount table won't work. Canonicalize path at the
beginning then.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
The virFileInData() function should return to the caller if the
current position the passed file is in is a data section or a
hole (and also how long the current section is). At any rate,
upon return from this function (be it successful or not) the
original position in the file is restored. This may mess up with
errno which might have been set earlier. Save the errno into a
local variable so it can be restored for the caller's sake.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
The URI parser used by libvirt does not populate uri->path if the
trailing slash is missing. The code virStorageSourceParseBackingURI
would then not populate src->path.
As only NBD network disks are allowed to have the 'name' field in the
XML defining the disk source omitted we'd generate an invalid XML which
we'd not parse again.
Fix it by populating src->path with an empty string if the uri is
lacking slash.
As pointed out above NBD is special in this case since we actually allow
it being NULL. The URI path is used as export name. Since an empty
export does not make sense the new approach clears the src->path if the
trailing slash is present but nothing else.
Add test cases now to cover all the various cases for NBD and non-NBD
uris as there was to time only 1 test abusing the quirk witout slash for
NBD and all other URIs contained the slash or in case of NBD also the
export name.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
The name is misleading. Change it to 'uristr' so that 'path' can be
reused in the proper context later.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
There are couple of things wrong with the current implementation.
The first one is that in the first loop the code tries to build a
list of fuse.glusterfs mount points. Well, since the strings are
allocated in a temporary buffer and are not duplicated this
results in wrong decision made later in the code.
The second problem is that the code does not take into account
subtree mounts. For instance, if there's a fuse.gluster mounted
at /some/path and another FS mounted at /some/path/subdir the
code would not recognize this subdir mount.
Reported-by: Han Han <hhan@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
If the given path is already a mount point (e.g. a bind mount of
a file, or simply a direct mount point of a FS), then our code
fails to detect that because the first thing it does is cutting
off part after last slash '/'.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
On s390x the struct member f_type of statsfs is hard coded to 'unsigned
int'. Change virFileIsSharedFixFUSE() to take a 'long long int' and use
a temporary to avoid pointer-casting.
This fixes the following error:
../../src/util/virfile.c:3578:38: error: cast increases required alignment of target type [-Werror=cast-align]
virFileIsSharedFixFUSE(path, (long *) &sb.f_type);
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Bjoern Walk <bwalk@linux.ibm.com>
virFileReadValueUint does not log errors for non-existient files,
it merely returns -2.
Commit 12093f1 introduced this.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
This enables to use both cgroup v1 and v2 at the same time together
with libvirt. It is supported by kernel and there is valid use-case,
not all controllers are implemented in cgroup v2 so there might be
configurations where administrator would enable these missing
controllers in cgroup v1.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
In order to set CPU cfs period using cgroup v2 'cpu.max' interface
we need to load the current value of CPU cfs quota first because
format of 'cpu.max' interface is '$quota $period' and in order to
change 'period' we need to write 'quota' as well. Writing only one
number changes only 'quota'.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
In cgroups v2 we need to handle threads and processes differently.
If you need to move a process you need to write its pid into
cgrou.procs file and it will move the process with all its threads
as well. The whole process will be moved if you use tid of any thread.
In order to move only threads at first we need to create threaded group
and after that we can write the relevant thread tids into cgroup.threads
file. Threads can be moved only into cgroups that are children of
cgroup of its process.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
When creating cgroup hierarchy we need to enable controllers in the
parent cgroup in order to be usable. That means writing "+{controller}"
into cgroup.subtree_control file. We can enable only controllers that
are enabled for parent cgroup, that means we need to do that for the
whole cgroup tree.
Cgroups for threads needs to be handled differently in cgroup v2. There
are two types of controllers:
- domain controllers: these cannot be enabled for threads
- threaded controllers: these can be enabled for threads
In addition there are multiple types of cgroups:
- domain: normal cgroup
- domain threaded: a domain cgroup that serves as root for threaded
cgroups
- domain invalid: invalid cgroup, can be changed into threaded, this
is the default state if you create subgroup inside
domain threaded group or threaded group
- threaded: threaded cgroup which can have domain threaded or
threaded as parent group
In order to create threaded cgroup it's sufficient to write "threaded"
into cgroup.type file, it will automatically make parent cgroup
"domain threaded" if it was only "domain". In case the parent cgroup
is already "domain threaded" or "threaded" it will modify only the type
of current cgroup. After that we can enable threaded controllers.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Cgroup v2 has only single mount point for all controllers. The list
of controllers is stored in cgroup.controllers file, name of controllers
are separated by space.
In cgroup v2 there is no cpuacct controller, the cpu.stat file always
exists with usage stats.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
If the placement was copied from parent or set to absolute path
there is nothing to do, otherwise set the placement based on
process placement from /proc/self/cgroup or /proc/{pid}/cgroup.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
When reconnecting to a domain we are validating the cgroup name.
In case of cgroup v2 we need to validate only the new format for host
without systemd '{machinename}.libvirt-{drivername}' or scope name
generated by systemd.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
