@@ -1826,6 +1826,70 @@ static void vfio_add_emulated_long(VFIOPCIDevice *vdev, int pos,
vfio_set_long_bits(vdev->emulated_config_bits + pos, mask, mask);
}
+/*
+ * For a cold-plugged device connected directly to a root port where
+ * vfio-pci reports AtomicOp completer support on the host, twiddle
+ * bits in the emulated root port to reflect this capability.
+ */
+static void vfio_pci_enable_rp_atomics(VFIOPCIDevice *vdev)
+{
+ struct vfio_device_info_cap_pci_atomic_comp *cap;
+ g_autofree struct vfio_device_info *info = NULL;
+ struct vfio_info_cap_header *hdr;
+ PCIDevice *parent;
+ uint32_t mask = 0;
+ PCIBus *bus;
+
+ /*
+ * XXX
+ * - Should this also be restricted to TYPE_VFIO_PCI_NOHOTPLUG devices?
+ * - Should we clear the capability on exit?
+ */
+ if (vdev->pdev.qdev.hotplugged) {
+ return;
+ }
+
+ info = vfio_get_device_info(vdev->vbasedev.fd);
+ if (!info) {
+ return;
+ }
+
+ hdr = vfio_get_device_info_cap(info, VFIO_DEVICE_INFO_CAP_PCI_ATOMIC_COMP);
+ if (!hdr) {
+ return;
+ }
+
+ cap = (void *)hdr;
+ if (cap->flags & VFIO_PCI_ATOMIC_COMP32) {
+ mask |= PCI_EXP_DEVCAP2_ATOMIC_COMP32;
+ }
+ if (cap->flags & VFIO_PCI_ATOMIC_COMP64) {
+ mask |= PCI_EXP_DEVCAP2_ATOMIC_COMP64;
+ }
+ if (cap->flags & VFIO_PCI_ATOMIC_COMP128) {
+ mask |= PCI_EXP_DEVCAP2_ATOMIC_COMP128;
+ }
+
+ if (!mask) {
+ return;
+ }
+
+ bus = pci_get_bus(&vdev->pdev);
+ parent = bus->parent_dev;
+
+ if (!parent || !pci_is_express(parent) || !parent->exp.exp_cap) {
+ return;
+ }
+
+ if (pcie_cap_get_type(parent) != PCI_EXP_TYPE_ROOT_PORT ||
+ pcie_cap_get_version(parent) != PCI_EXP_FLAGS_VER2) {
+ return;
+ }
+
+ pci_long_test_and_set_mask(parent->config + parent->exp.exp_cap +
+ PCI_EXP_DEVCAP2, mask);
+}
+
static int vfio_setup_pcie_cap(VFIOPCIDevice *vdev, int pos, uint8_t size,
Error **errp)
{
@@ -1929,6 +1993,8 @@ static int vfio_setup_pcie_cap(VFIOPCIDevice *vdev, int pos, uint8_t size,
QEMU_PCI_EXP_LNKCAP_MLS(QEMU_PCI_EXP_LNK_2_5GT), ~0);
vfio_add_emulated_word(vdev, pos + PCI_EXP_LNKCTL, 0, ~0);
}
+
+ vfio_pci_enable_rp_atomics(vdev);
}
/*
For cold-plug configurations where the vfio-pci device reports enabled support for PCIe AtomicOps completers and we have a compatible VM configuration, mirror the host AtomicOps completer support in the virtual root port. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> --- hw/vfio/pci.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+)