Preserve vfio INTX state across cpr-exec. Preserve VFIOINTx fields as
follows:
pin : Recover this from the vfio config in kernel space
interrupt : Preserve its eventfd descriptor across exec.
unmask : Ditto
route.irq : This could perhaps be recovered in vfio_pci_post_load by
calling pci_device_route_intx_to_irq(pin), whose implementation reads
config space for a bridge device such as ich9. However, there is no
guarantee that the bridge vmstate is read before vfio vmstate. Rather
than fiddling with MigrationPriority for vmstate handlers, explicitly
save route.irq in vfio vmstate.
pending : save in vfio vmstate.
mmap_timeout, mmap_timer : Re-initialize
bool kvm_accel : Re-initialize
In vfio_realize, defer calling vfio_intx_enable until the vmstate
is available, in vfio_pci_post_load. Modify vfio_intx_enable and
vfio_intx_kvm_enable to skip vfio initialization, but still perform
kvm initialization.
Signed-off-by: Steve Sistare <steven.sist...@oracle.com>
---
hw/vfio/pci.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 47 insertions(+), 4 deletions(-)
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index f0213e0..b5e7592 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -184,12 +184,17 @@ static bool vfio_intx_enable_kvm(VFIOPCIDevice *vdev,
Error **errp)
return true;
}
+ if (vdev->vbasedev.reused) {
+ goto skip_state;
+ }
+
/* Get to a known interrupt state */
qemu_set_fd_handler(irq_fd, NULL, NULL, vdev);
vfio_mask_single_irqindex(&vdev->vbasedev, VFIO_PCI_INTX_IRQ_INDEX);
vdev->intx.pending = false;
pci_irq_deassert(&vdev->pdev);
+skip_state:
/* Get an eventfd for resample/unmask */
if (vfio_notifier_init(vdev, &vdev->intx.unmask, "intx-unmask", 0)) {
error_setg(errp, "vfio_notifier_init intx-unmask failed");
@@ -204,6 +209,10 @@ static bool vfio_intx_enable_kvm(VFIOPCIDevice *vdev,
Error **errp)
goto fail_irqfd;
}
+ if (vdev->vbasedev.reused) {
+ goto skip_irq;
+ }
+
if (!vfio_set_irq_signaling(&vdev->vbasedev, VFIO_PCI_INTX_IRQ_INDEX, 0,
VFIO_IRQ_SET_ACTION_UNMASK,
event_notifier_get_fd(&vdev->intx.unmask),
@@ -214,6 +223,7 @@ static bool vfio_intx_enable_kvm(VFIOPCIDevice *vdev, Error
**errp)
/* Let'em rip */
vfio_unmask_single_irqindex(&vdev->vbasedev, VFIO_PCI_INTX_IRQ_INDEX);
+skip_irq:
vdev->intx.kvm_accel = true;
trace_vfio_intx_enable_kvm(vdev->vbasedev.name);
@@ -329,7 +339,13 @@ static bool vfio_intx_enable(VFIOPCIDevice *vdev, Error
**errp)
return true;
}
- vfio_disable_interrupts(vdev);
+ /*
+ * Do not alter interrupt state during vfio_realize and cpr load. The
+ * reused flag is cleared thereafter.
+ */
+ if (!vdev->vbasedev.reused) {
+ vfio_disable_interrupts(vdev);
+ }
vdev->intx.pin = pin - 1; /* Pin A (1) -> irq[0] */
pci_config_set_interrupt_pin(vdev->pdev.config, pin);
@@ -351,7 +367,8 @@ static bool vfio_intx_enable(VFIOPCIDevice *vdev, Error
**errp)
fd = event_notifier_get_fd(&vdev->intx.interrupt);
qemu_set_fd_handler(fd, vfio_intx_interrupt, NULL, vdev);
- if (!vfio_set_irq_signaling(&vdev->vbasedev, VFIO_PCI_INTX_IRQ_INDEX, 0,
+ if (!vdev->vbasedev.reused &&
+ !vfio_set_irq_signaling(&vdev->vbasedev, VFIO_PCI_INTX_IRQ_INDEX, 0,
VFIO_IRQ_SET_ACTION_TRIGGER, fd, errp)) {
qemu_set_fd_handler(fd, NULL, NULL, vdev);
vfio_notifier_cleanup(vdev, &vdev->intx.interrupt, "intx-interrupt",
0);
@@ -3262,7 +3279,8 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
vfio_intx_routing_notifier);
vdev->irqchip_change_notifier.notify = vfio_irqchip_change;
kvm_irqchip_add_change_notifier(&vdev->irqchip_change_notifier);
- if (!vfio_intx_enable(vdev, errp)) {
+ /* Wait until cpr load reads intx routing data to enable */
+ if (!vdev->vbasedev.reused && !vfio_intx_enable(vdev, errp)) {
goto out_deregister;
}
}
@@ -3578,12 +3596,36 @@ static int vfio_pci_post_load(void *opaque, int
version_id)
vfio_claim_vectors(vdev, nr_vectors, false);
} else if (vfio_pci_read_config(pdev, PCI_INTERRUPT_PIN, 1)) {
- g_assert_not_reached(); /* completed in a subsequent patch */
+ Error *err = NULL;
+ if (!vfio_intx_enable(vdev, &err)) {
+ error_report_err(err);
+ return -1;
+ }
}
return 0;
}
+static const VMStateDescription vfio_intx_vmstate = {
+ .name = "vfio-intx",
+ .version_id = 0,
+ .minimum_version_id = 0,
+ .fields = (VMStateField[]) {
+ VMSTATE_BOOL(pending, VFIOINTx),
+ VMSTATE_UINT32(route.mode, VFIOINTx),
+ VMSTATE_INT32(route.irq, VFIOINTx),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+#define VMSTATE_VFIO_INTX(_field, _state) { \
+ .name = (stringify(_field)), \
+ .size = sizeof(VFIOINTx), \
+ .vmsd = &vfio_intx_vmstate, \
+ .flags = VMS_STRUCT, \
+ .offset = vmstate_offset_value(_state, _field, VFIOINTx), \
+}
+
static const VMStateDescription vfio_pci_vmstate = {
.name = "vfio-pci",
.version_id = 0,
@@ -3595,6 +3637,7 @@ static const VMStateDescription vfio_pci_vmstate = {
.fields = (VMStateField[]) {
VMSTATE_PCI_DEVICE(pdev, VFIOPCIDevice),
VMSTATE_MSIX_TEST(pdev, VFIOPCIDevice, vfio_msix_present),
+ VMSTATE_VFIO_INTX(intx, VFIOPCIDevice),
VMSTATE_END_OF_LIST()
}
};
--
1.8.3.1
