The term "ignored" is a better choice for the filtering performed
on devices from udev.
Reviewed-by: NPeter Krempa <pkrempa@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

In order to allow libvirt to create and start new mediated devices, we
need to be able to verify that the device has been started. In order to
do this, we'll need to save the UUID of newly-discovered devices within
the virNodeDevCapMdev structure. This allows us to search the device
list by UUID and verify whether the expected device has been started.
Signed-off-by: NJonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: NErik Skultety <eskultet@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

When a device is "move"-d (this basically means it was renamed),
we add the new device onto our list but keep the old there too.
Fortunately, udev sets this DEVPATH_OLD property which points to
the old device path. We can use it to remove the old instance.

To test this try renaming an interface, for instance:

  # ip link set tunl0 name tunl1
  # ip link set tunl1 name tunl0

One problem with udev is that it sends old ifname in INTERFACE
property, which creates a problem for us, the property is where
we get the ifname from and use it then to query all kind of info
about the interface. Well, if it is non-existent then we can't
query anything. This happens if ifname rename is suppressed
(net.ifnames=0 on kernel cmd line for instance). Fortunately, we
can use "kernel" source for udev events which has always the
fresh info.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NMartin Kletzander <mkletzan@redhat.com>

Move internals of udevRemoveOneDevice() into a separate function
which accepts sysfs path as an argument and actually removes the
device from the internal list. It will be reused later.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NMartin Kletzander <mkletzan@redhat.com>

When removing a node device object from the internal list the
udevRemoveOneDevice() function does plain unref over the object.
This is not sufficient. If there is another thread that's waiting
for the object lock it will wait forever.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

It is possible and common to rename some devices, this is especially
true for ethernet devices such as veth pairs.

In the udevEventHandleThread() we will be notified of this change but
currently we only process "add", "change" and "remove"
events. Renaming a device such as above results in a "move" event, not
a "remove" followed by and "add" or vise versa. This change will add
the new/destination device to our records but unfortunately there is
no usable mechanism to identify the old/source device to remove it
from the records. So this is admittedly only a partial fix.
Signed-off-by: NMark Asselstine <mark.asselstine@windriver.com>
Reviewed-by: NMartin Kletzander <mkletzan@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

During startup the udev node device driver impl uses a background thread
to populate the list of devices to avoid blocking the daemon startup
entirely. There is no synchronization to the public APIs, so it is
possible for an application to start calling APIs before the device
initialization is complete.

This was not a problem in the old approach where libvirtd was started
on boot, as initialization would easily complete before any APIs were
called.

With the use of socket activation, however, APIs are invoked from the
very moment the daemon starts. This is easily seen by doing a

  'virsh -c nodedev:///system list'

the first time it runs it will only show one or two devices. The second
time it runs it will show all devices. The solution is to introduce a
flag and condition variable for APIs to synchronize against before
returning any data.
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Historically threads are given a name based on the C function,
and this name is just used inside libvirt. With OS level thread
naming this name is now visible to debuggers, but also has to
fit in 15 characters on Linux, so function names are too long
in some cases.
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Include virutil.h in all files that use it,
instead of relying on it being pulled in somehow.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>

The intent here is to allow the virt drivers to be run directly embedded
in an arbitrary process without interfering with libvirtd. To achieve
this they need to store all their configuration & state in a separate
directory tree from the main system or session libvirtd instances.

This can be useful for doing testing of the virt drivers in "make check"
without interfering with the user's own libvirtd instances.

It can also be used for applications using KVM/QEMU as a piece of
infrastructure to build an service, rather than for general purpose
OS hosting. A long standing example is libguestfs, which would prefer
if its temporary VMs did show up in the main libvirtd VM list, because
this confuses apps such as OpenStack Nova. A more recent example would
be Kata which is using KVM as a technology to build containers.
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NCole Robinson <crobinso@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

The last_component() method is a GNULIB custom function
that returns a pointer to the base name in the path.
This is similar to g_path_get_basename() but without the
malloc. The extra malloc is no trouble for libvirt's
needs so we can use g_path_get_basename().
Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

virGetUserRuntimeDirectory() *never* *ever* returns NULL, making the
checks for it completely unnecessary.
Signed-off-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>
Reviewed-by: NCole Robinson <crobinso@redhat.com>

Signed-off-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>

The function now does not return an error so we can drop it fully.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Replace all occurrences of
  if (VIR_STRDUP(a, b) < 0)
     /* effectively dead code */
with:
  a = g_strdup(b);
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Replace:
  if (!s && VIR_STRDUP(s, str) < 0)
    goto;
with:
  if (!s)
    s = g_strdup(str);
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Replace all the occurrences of
  ignore_value(VIR_STRDUP(a, b));
with
  a = g_strdup(b);
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Since commit 44e7f029
    util: rewrite auto cleanup macros to use glib's equivalent

VIR_AUTOFREE is just an alias for g_autofree. Use the GLib macros
directly instead of our custom aliases.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Prefer the GLib version of the macro.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Use G_GNUC_UNUSED from GLib instead of ATTRIBUTE_UNUSED.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

All code using LOCALSTATEDIR "/run" is updated to use RUNSTATEDIR
instead. The exception is the remote driver client which still
uses LOCALSTATEDIR "/run". The client needs to connect to remote
machines which may not be using /run, so /var/run is more portable
due to the /var/run -> /run symlink.

Some duplicate paths in the apparmor code are also purged.

There's no functional change by default yet since both expressions
expand to the same value.
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

When running in libvirtd, we are happy for any of the drivers to simply
skip their initialization in virStateInitialize, as other drivers are
still potentially useful.

When running in per-driver daemons though, we want the daemon to abort
startup if the driver cannot initialize itself, as the daemon will be
useless without it.
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

When the drivers acquire their pidfile lock we don't want to wait if the
lock is already held. We need the driver to immediately report error,
causing the daemon to exit.
Reviewed-by: NErik Skultety <eskultet@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

When we allow multiple instances of the driver for the same user
account, using a separate root directory, we need to ensure mutual
exclusion. Use a pidfile to guarantee this.

In privileged libvirtd this ends up locking

   /var/run/libvirt/nodedev/driver.pid

In unprivileged libvirtd this ends up locking

  /run/user/$UID/libvirt/nodedev/run/driver.pid

NB, the latter can vary depending on $XDG_RUNTIME_DIR
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

It has been exported by systemd commit
commit a571c23e954cb88cdd5faa28593b19bd7c340130
    libudev: export udev_monitor_set_receive_buffer_size()
released in v183.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPavel Hrdina <phrdina@redhat.com>

The function was deprecated in udev 219 and all the supported OSes
don't have older version of udev or systemd.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Commit 3bd4ed46 introduced this element as required which
breaks backcompat for test driver. Let's make the element optional.
Reviewed-by: NErik Skultety <eskultet@redhat.com>
Signed-off-by: NNikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>

Vim treats *.h files as cpp ones with respect to syntax highlighting.
Thus "class" in _virNodeDevCapPCIDev highlighted mistakenly.
This can be fixed by filetype detection code tunables but it
is more convinient to skip this tuning by every project member.

Let's just use "klass" as field name instead of _class or class
and add syntax rule.
Signed-off-by: NNikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

Signal the udev thread the change of `priv->threadQuit` by using the
thread condition.
Signed-off-by: NMarc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

If the udev thread is stopped, it must be ensured that the watch
handle is also removed from the main loop.
Signed-off-by: NMarc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

Even if an error is reported by `udev_enumerate_scan_devices`,
e.g. because a driver of a device has an bug, we can still enumerate
all other devices. Additionally the documentation of
udev_enumerate_scan_devices says that on success an integer >= 0 is
returned (see man udev_enumerate_scan_devices(3)).
Reviewed-by: NBjoern Walk <bwalk@linux.ibm.com>
Signed-off-by: NMarc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

Missing semicolon at the end of macros can confuse some analyzers
(like cppcheck <filename>). VIR_ONCE_GLOBAL_INIT is almost
exclusively called without an ending semicolon, but let's
standardize on using one like the other macros.

Add a dummy struct definition at the end of the macro, so
the compiler will require callers to add a semicolon.
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.

In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.

With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to  find the
author of a particular bit of code.

This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.

The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.
Reviewed-by: NErik Skultety <eskultet@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Commit cdbe1332 neglected to document the API. So let's add some
details about the algorithm and why it was used to help future
readers understand the issues encountered.

NB: Management of the processing udev device notification is a
delicate balance between the udev process, the scheduler, and when
exactly the data from/for the socket is received. The balance is
particularly important for environments when multiple devices are
added into the system more or less simultaneously such as is done
for mdev or SRIOV. In these cases old libudev blocking on the udev
recv() occurs more frequently. It's expected that future devices
will follow similar algorithms. Even though the algorithm does
present some challenges for older OS's (such as Centos 6), trying
to rewrite the algorithm to fit both models would be more complex
and involve pulling the monitor object out of the private data
lockable object and would need to be guarded by a separate lock.
Devising such an algorithm to work around issues with older OS's
at the expense of more modern OS algorithms in newer event processing
code may result in unexpected issues, so the choice is to encourage
use of newer OS's with newer udev event processing code.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>
Reviewed-by: NErik Skultety <eskultet@redhat.com>

And remove NULL checking from all callers.
Signed-off-by: NAnya Harter <aharter@redhat.com>

So far we are repeating the following lines over and over:

  if (!(virSomeObjectClass = virClassNew(virClassForObject(),
                             "virSomeObject",
                             sizeof(virSomeObject),
                             virSomeObjectDispose)))
      return -1;

While this works, it is impossible to do some checking. Firstly,
the class name (the 2nd argument) doesn't match the name in the
code in all cases (the 3rd argument). Secondly, the current style
is needlessly verbose. This commit turns example into following:

  if (!(VIR_CLASS_NEW(virSomeObject,
                      virClassForObject)))
      return -1;
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

Declare what URI schemes a driver supports in its virConnectDriver
struct. This allows us to skip trying to open the driver entirely
if the URI scheme doesn't match.
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Add a localOnly flag to the virConnectDriver struct which allows a
driver to indicate whether it is local-only, or permits remote
connections. Stateful drivers running inside libvirtd are generally
local only. This allows us to remote the check for uri->server != NULL
from most drivers.
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>