Commit f4ef3a71 made a variation of virNetDevSetMAC that would return
without logging an error message if errno was set to
EADDRNOTAVAIL. This errno is set by some SRIOV VF drivers (in
particular igbvf) when they fail to set the device's MAC address due
to the PF driver refusing the request. This is useful if we want to
try a different method of setting the VF MAC address before giving up
(Commit 86556e16 actually does this, setting the desired MAC address
to the "admin MAC in the PF, then detaching and reattaching the VF
netdev driver to force a reinit of the MAC address).

During testing of Bug 1442040 t was discovered that the ixgbe driver
returns EPERM in this situation, so this patch changes the exception
case for silent+non-terminal failure to account for this difference.

Completes resolution to: https://bugzilla.redhat.com/1415609 (RHEL 7.4)
                         https://bugzilla.redhat.com/1442040 (RHEL 7.3.z)

The current fallback stub for virNetDevSetCoalesce is inside an
earlier conditional block. This deals with the feature being
missing on older Linux platforms. We need a second fallback stub
though, outside the top level conditional, to ensure builds work
on Win32/FreeBSD platforms too.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

That function is able to configure coalesce settings for an interface,
similarly to 'ethtool -C'.  This function also updates back the
structure so that it contains actual data on the device (if the device
doesn't support some settings kernel might just return 0 and not set
whatever is not supported), so this way we'll have up-to-date
information in the live domain XML.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

If if_indextoname is not defined, the whole function using it should
not be defined either.  Add stub to fix build on mingw.

Caused by 5dd60705Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Fix typo: virNetDevVLanPtr -> virNetDevVlanPtr.

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Having this information available will make it easier to determine the
culprit when MAC or vlan tag appear to not be set, eg.:

  https://bugzilla.redhat.com/1364073

(This patch doesn't fix that bug, just makes it easier to diagnose)

If an SRIOV VF has previously been used for VFIO device assignment,
the "admin MAC" that is stored in the PF driver's table of VF info
will have been set to the MAC address that the virtual machine wanted
the device to have. Setting the admin MAC for a VF also sets a flag in
the PF that is loosely called the "administratively set" flag. Once
that flag is set, it is no longer possible for the net driver of the
VF (either on the host or in a virtual machine) to directly set the
VF's MAC again; this flag isn't reset until the *PF* driver is
restarted, and that requires taking *all* VFs offline, so it's not
really feasible to do.

If the same SRIOV VF is later used for macvtap passthrough mode, the
VF's MAC address must be set, but normally we don't unbind the VF from
its host net driver (since we actually need the host net driver in
this case). Since setting the VF MAC directly will fail, in the past
"we" ("I") had tried to fix the problem by simply setting the admin MAC
(via the PF) instead. This *appeared* to work (and might have at one
time, due to promiscuous mode being turned on somewhere or something),
but it currently creates a non-working interface because only the
value for admin MAC is set to the desired value, *not* the actual MAC
that the VF is using.

Earlier patches in this series reverted that behavior, so that we once
again set the MAC of the VF itself for macvtap passthrough operation,
not the admin MAC. But that brings back the original bug - if the
interface has been used for VFIO device assignment, you can no longer
use it for macvtap passthrough.

This patch solves that problem by noticing when virNetDevSetMAC()
fails for a VF, and in that case it sets the desired MAC to the admin
MAC via the PF, then "bounces" the VF driver (by unbinding and the
immediately rebinding it to the VF). This causes the VF's MAC to be
reinitialized from the admin MAC, and everybody is happy (until the
*next* time someone wants to set the VF's MAC address, since the
"administratively set" bit is still turned on).

Some PF drivers allow setting the admin MAC (that is the MAC address
that the VF will be initialized to the next time the VF's driver is
loaded) to 00:00:00:00:00:00, and some don't. Multiple drivers
initialize the admin MACs to all 0, but don't allow setting it to that
very same value. It has been an uphill battle convincing the driver
people that it's reasonable to expect The argument that's used is
that an all 0 device MAC address on a device is invalid; however, from
an outsider's point of view, when the admin MAC is set to 0 at the
time the VF driver is loaded, the VF's MAC is *not* set to 0, but to a
random non-0 value. But that's beside the point - even if I could
convince one or two SRIOV driver maintainers to permit setting the
admin MAC to 0, there are still several other drivers.

So rather than fighting that losing battle, this patch checks for a
failure to set the admin MAC due to an all 0 value, and retries it
with 02:00:00:00:00:00. That won't result in a random value being set
in the VF MAC at next VF driver init, but that's okay, because we
always want to set a specific value anyway. Rather, the "almost 0"
setting makes it easy to visually detect from the output of "ip link
show" which VFs are currently in use and which are free.

The global functions virNetDevReplaceMacAddress(),
virNetDevReplaceNetConfig(), virNetDevRestoreMacAddress(), and
virNetDevRestoreNetConfig() are no longer used, as their functionality
has been replaced by virNetDev(Save|Read|Set)NetConfig().

The static functions virNetDevReplaceVfConfig() and
virNetDevRestoreVfConfig() were only used by the above-named global
functions that were removed.

These three functions are destined to replace
virNetDev(Replace|Restore)NetConfig() and
virNetDev(Replace|Restore)MacAddress(), which both do the save and set
together as a single step. We need to separate the save, read, and set
steps because there will be situations where we need to do something
else in between (in particular, we will need to rebind a VF's driver
after save but before set).

This patch creates the new functions, but doesn't call them - that
will come in a subsequent patch. Note that the new functions to
read/write the file that stores the original network config now uses
JSON rather than plaintext (it still recognizes the old format as well
though, so it won't get confused during an upgrade).

Fix typo in virNetDevPFGetVF() stub:

  ATTRUBUTE_UNUSED -> ATTRIBUTE_UNUSED.

While here, use common indent style for arguments in
virNetDevGetVirtualFunctionIndex() stub.

Given an SRIOV PF netdev name (e.g. "enp2s0f0") and VF#, this new
function returns the netdev name of the referenced VF device
(e.g. "enp2s11f6"), or NULL if the device isn't bound to a net driver.

We will want to allow silent failure of virNetDevSetMAC() in the case
that the SIOSIFHWADDR ioctl fails with errno == EADDRNOTAVAIL. (Yes,
that is very specific, but we really *do* want a logged failure in all
other circumstances, and don't want to duplicate code in the caller
for the other possibilities).

This patch renames the 3 different virNetDevSetMAC() functions to
virNetDevSetMACInternal(), adding a 3rd arg called "quiet" and making
them static (because this extra control will only be needed within
virnetdev.c). A new global virNetDevSetMAC() is defined that calls
whichever of the three *Internal() functions gets compiled with quiet
= false. Callers in virnetdev.c that want to notice a failure with
errno == EADDRNOTAVAIL and retry with a different strategy rather than
immediately failing, can call virNetDevSetMACInternal(..., true).

...and cleanup the callers to report it when it *is* an error.

In many cases It's useful for virPCIGetNetName() to not log an error
and simply return a NULL pointer when the given device isn't bound to
a net driver (e.g. we're looking at a VF that is permanently bound to
vfio-pci). The existing code would silently return an error in this
case, which could eventually lead to the dreaded "An error occurred
but the cause is unknown" log message.

This patch changes virPCIGetNetName() to still return success if the
device simply isn't bound to a net driver, and adjusts all the callers
that require a non-null netname to check for that condition and log an
error when it happens.

This function is only called in two places, and the ifindex,
nltarget_kernel, and getPidFunc args are never used (and never will
be).

ifindex - we always know the name of the device, and never know the
ifindex - if we really did need the ifindex we would have to get it
from the name using virNetDevGetIndex(). In practice, we just send -1
to virNetDevSetVfConfig(), which doesn't bother to learn the real
ifindex (you only need a name *or* an ifindex for the netlink command
to succeed, not both).

nltarget_kernel - messages to set the config of an SRIOV VF will
always go to netlink in the kernel, not to another user process, so
this arg is always true (there are other uses of netlink messages
where the message might need to go to another user process, but never
in the case of RTM_SETLINK for SRIOV).

getPidFunc - this arg is only used if nltarget_kernel is false, and it
never is.

None of this has any functional effect, it just makes it easier to
follow what's happening when virNetDevSetVfConfig() is called.

virNetDevParseVfConfig() assumed that both the MAC address and VLAN
tag pointers were valid, so even if you only wanted one or the other,
you would need a variable to hold the returned value for both. This
patch checks each for a NULL pointer before filling it in.

Decorate unused arguments of the virNetDevGetMaster() stub
with ATTRIBUTE_UNUSED to fix build on systems where this
stub is used.

This function provides the bridge/bond device that the given network
device is attached to. The return value is 0 or -1, and the master
device is a char** argument to the function - this is needed in order
to allow for a "success" return from a device that has no master.

The only reason that the ethtool features weren't being retrieved in
an unprivileged libvirtd was because they required ioctl(), and the
ioctl was using an AF_PACKET socket, which requires root. Now that we
are using AF_UNIX for ioctl(), this restriction can be removed.

The exact family of the socket created for the fd used by ioctl(7)
doesn't matter, it just needs to be a socket and not a file. But for
some reason when macvtap support was added, it used
AF_PACKET/SOCK_DGRAM sockets for its ioctls; we later used the same
AF_PACKET/SOCK_DGRAM socket for new ioctls we added, and eventually
modified the other pre-existing ioctl sockets (for creating/deleting
bridges) to also use AF_PACKET/SOCK_DGRAM (that code originally used
AF_UNIX/SOCK_STREAM).

The problem with using AF_PACKET (intended for sending/receiving "raw"
packets, i.e. packets that can be some protocol other than TCP or UDP)
is that it requires root privileges. This meant that none of the
ioctls in virnetdev.c or virnetdevip.c would work when running
libvirtd unprivileged.

This packet solves that problem by changing the family to AF_UNIX when
creating the socket used for any ioctl().

Add a function getting the name of a network interface out of its index.

Before 9c17d665 (v1.3.2 - I know, right?) it was possible to
have the following interface configuration:

  <interface type='ethernet'/>
    <script path=''/>
  </interface>

This resulted in -netdev tap,script=,.. Fortunately, qemu helped
us to get away with this as it just ignored the empty script
path. However, after the commit mentioned above it's libvirtd
who is executing the script. Unfortunately without special
case-ing empty script path.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

This patch splits virnetdev.[ch] into multiple files, with the new
virnetdevip.[ch] containing all the functions related to setting and
retrieving IP-related info for a device (both addresses and routes).

These had been declared in conf/device_conf.h, but then used in
util/virnetdev.c, meaning that we had to #include conf/device_conf.h
in virnetdev.c (which we have for a long time said shouldn't be done.

This caused a bigger problem when I tried to #include util/virnetdev.h
in a file in src/conf (which is allowed) - for some reason the
"device_conf.h: File not found" error.

The solution is to move the data types and functions used in util
sources from conf to util. Some names were adjusted during the move
("virInterface" --> "virNetDevIf", and "VIR_INTERFACE" -->
"VIR_NETDEV_IF")

virNetDevLinkDump should have been in virnetlink.c, but that file
didn't exist yet when the function was created. It didn't really
matter until now - I found that having virnetlink.h included by
virnetdev.h caused build problems when trying to #include virnetdev.h
in a .c file in src/conf (due to missing directory in -I). Rather than
fix that to further institutionalize the incorrect placement of this
one function, this patch moves the function.

Switch from opendir to virDirOpen everywhere we need to report an error.

The directories we iterate over are unlikely to contain any entries
starting with a dot, other than '.' and '..' which is already skipped
by virDirRead.

Introduce a helper that only calls closedir if DIR* is non-NULL
and sets it to NULL afterwards.

Commit b3d06987 added peer address setting to the low level
virNetDevSetIPAddress() function, but ended up causing a segfault in
cases where the caller passed NULL for peer address.

Commit a3510e33 fixed the segfault, but managed to cause us to
skip setting the broadcast address when setting an interface's IP
address. The result is that the broadcast address is 0.0.0.0 for all
libvirt-created bridges (and interfaces in lxc containers with IP
addresses set by libvirt).

This was reported on the mailing list:

  https://www.redhat.com/archives/libvir-list/2016-June/msg00027.html

but I was too busy to investigate at the time. I found it by accident
today while refactoring virNetDevSetIPAddress(). Since this regression
is present in the 1.3.5 release, I'm sending the bugfix as a separate
patch from my larger refactoring patchset.

s/ATTRIBUGE/ATTRIBUTE/
Reported-by: NOlaf Hering <olaf@aepfle.de>

This speeds up node_device_udev driver startup 11x.

Simplify the logic

Move out the code depending on HAVE_DECL_ETHTOOL_GFEATURES.

Split out the features that we probe via various ethtool commands
and ETHTOOL_GFLAGS.

Rename struct elem to virNetDevEthtoolFeatureCmd and move it
out of the function to allow reusing it.

SRIOV VFs used in macvtap passthrough mode can take advantage of the
SRIOV card's transparent vlan tagging. All the code was there to set
the vlan tag, and it has been used for SRIOV VFs used for hostdev
interfaces for several years, but for some reason, the vlan tag for
macvtap passthrough devices was stubbed out with a -1.

This patch moves a bit of common validation down to a lower level
(virNetDevReplaceNetConfig()) so it is shared by hostdev and macvtap
modes, and updates the macvtap caller to actually send the vlan config
instead of -1.

This is just a wrapper for virCommand that takes two strings
and runs them.

Move it to virnetdev.c for easier mocking.