Rollback of FD sets passed to qemu is also needed after possible restart
of libvirtd when we need to serialize the data into status XML. For this
purpose we need to access the fdset ID once it was passed to qemu and
potentially re-create a 'qemuFDPass' struct in passed state.
Introduce 'qemuFDPassNewPassed' and 'qemuFDPassIsPassed'.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Until now the code didn't expect that we'd want to rollback/detach a FD
passed on the commandline, but whith disk backend FD passing this can
happen.
Properly mark the 'qemuFDPass' object as passed to qemu even when it was
done on the commandline.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
We need to use the 'name' variable and just overwrite it with the FD
number when FDs are passed on the monitor. Otherwise we will read NULL
path if the FD is accessed before being passed on the monitor. The idea
of this helper is to simplify the monitor code so it would be
counterproductive to have other behaviour.
Fixes the following symptom:
$ virsh attach-interface cd network default --model virtio
error: Failed to attach interface
error: internal error: unable to execute QEMU command 'netdev_add': File descriptor named '(null)' has not been found
Fixes: bca9047906
Resolves: https://gitlab.com/libvirt/libvirt/-/issues/318
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2092856
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
When dealing with fdsets only we don't need to pass the FD first as we
now generate fdset name directly. Also there are no more caveats in
passing multiple FDs.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Now that the 'direct' mode was separated and thus we don't have any
possible error case we can stop returning any values and simplify
callers.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This finishes the separation of the fdset and direct helpers. Remove
'qemuFDPassNewDirect' and all internals which were applicable only in
direct mode.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The callers adding the FDs are validating them regardless so this check
was redundant.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Originally I envisioned a common set of APIs for both FD passing
approaches but it turns out they are not really compatible enough for it
to make sense to use one set of APIs.
As of such introduce a distinct set of APIs for the 'direct' mode, which
will later be used to convert all places that currently use
'qemuFDPassNewDirect' and later clean up the existing APIs.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
We don't want to keep the FDs open more than we need to.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The only caller doesn't use the fdset info any more.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
If we use our own fdset ID when hot-adding a fdset we can vastly
simplify our internals.
As a stop-gap when a fdset would be added behind libvirt's back we'll
validated that the fdset to be added is not yet used.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
It's effectively replaced by checks in qemuFDPassTransfer. This will
simplify cleanup paths on constructing the qemuFDPass object when FDs
are being handled.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Add validation to the transfer step to make the adding step more simple
for easier cleanup paths.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Add possibility to delay checks to the point when the FDs are to be
passed to qemu.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The existing helpers we have are very clumsy and there's no integration
with the monitor.
This patch introduces new helpers to bridge the gap and simplify handing
of fdsets and classic FD passing when generating commandline/hotplug
arguments.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
