vfio-pci and pci-assign both do this on their own for setting up
direct MSI injection through KVM. Provide a helper function for
this in MSI code.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Added (msi|msix)_set_message() function for whoever might
want to use them.
Currently msi_notify()/msix_notify() write to these vectors to
signal the guest about an interrupt so the correct values have to
written there by the guest or QEMU.
For example, POWER guest never initializes MSI/MSIX vectors, instead
it uses RTAS hypercalls. So in order to support MSIX for virtio-pci on
POWER we have to initialize MSI/MSIX message from QEMU.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Also this functions is better invoked by the core than by each and every
device. This allows to drop the config_write callbacks from ich and
intel-hda.
CC: Alexander Graf <agraf@suse.de>
CC: Gerd Hoffmann <kraxel@redhat.com>
CC: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Terminate msi/msix_write_config early if support is not enabled. This
allows to remove checks at the caller site if MSI is optional.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Rename msix_supported to msi_supported and control MSI and MSI-X
activation this way. That was likely to original intention for this
flag, but MSI support came after MSI-X.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
msi_init may fail, so we need to check on uninit if the cap was
actually installed. This also avoids that the users need to check.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
config write handlers should be idempotent.
So no need for complex range checks: a simple
one checking that we are touching the relevant capability
will do.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Extract range functions from pci.h. These will be used by later patches
by non-PCI devices. Adjust current users.
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
(cherry picked from commit bf1b007123)
