Finish cpr for vfio-pci MSI/MSI-X devices by preserving eventfd's and vector state.
Signed-off-by: Steve Sistare <steven.sist...@oracle.com> --- hw/vfio/pci.c | 103 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 102 insertions(+), 1 deletion(-) diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index acac8a7..abef9b2 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -49,17 +49,55 @@ static void vfio_disable_interrupts(VFIOPCIDevice *vdev); static void vfio_mmap_set_enabled(VFIOPCIDevice *vdev, bool enabled); +#define EVENT_FD_NAME(vdev, name) \ + g_strdup_printf("%s_%s", (vdev)->vbasedev.name, (name)) + +static int save_event_fd(VFIOPCIDevice *vdev, const char *name, int nr, + EventNotifier *ev) +{ + int fd = event_notifier_get_fd(ev); + + if (fd >= 0) { + g_autofree char *fdname = EVENT_FD_NAME(vdev, name); + int old_fd = cpr_find_fd(fdname, nr); + if (old_fd < 0) { + cpr_save_fd(fdname, nr, fd); + } else if (old_fd != fd) { + error_report("fd %s %d already saved with a different value %d", + name, fd, old_fd); + return 1; + } + } + return 0; +} + +static int load_event_fd(VFIOPCIDevice *vdev, const char *name, int nr) +{ + g_autofree char *fdname = EVENT_FD_NAME(vdev, name); + int fd = cpr_find_fd(fdname, nr); + return fd; +} + +static void delete_event_fd(VFIOPCIDevice *vdev, const char *name, int nr) +{ + g_autofree char *fdname = EVENT_FD_NAME(vdev, name); + cpr_delete_fd(fdname, nr); +} + /* Create new or reuse existing eventfd */ static int vfio_notifier_init(VFIOPCIDevice *vdev, EventNotifier *e, const char *name, int nr) { - int fd = -1; /* placeholder until a subsequent patch */ int ret = 0; + int fd = load_event_fd(vdev, name, nr); if (fd >= 0) { event_notifier_init_fd(e, fd); } else { ret = event_notifier_init(e, 0); + if (!ret) { + save_event_fd(vdev, name, nr, e); + } } return ret; } @@ -67,6 +105,7 @@ static int vfio_notifier_init(VFIOPCIDevice *vdev, EventNotifier *e, static void vfio_notifier_cleanup(VFIOPCIDevice *vdev, EventNotifier *e, const char *name, int nr) { + delete_event_fd(vdev, name, nr); event_notifier_cleanup(e); } @@ -2736,6 +2775,11 @@ static void vfio_register_err_notifier(VFIOPCIDevice *vdev) fd = event_notifier_get_fd(&vdev->err_notifier); qemu_set_fd_handler(fd, vfio_err_notifier_handler, NULL, vdev); + /* Do not alter irq_signaling during vfio_realize for cpr */ + if (vdev->pdev.reused) { + return; + } + if (vfio_set_irq_signaling(&vdev->vbasedev, VFIO_PCI_ERR_IRQ_INDEX, 0, VFIO_IRQ_SET_ACTION_TRIGGER, fd, &err)) { error_reportf_err(err, VFIO_MSG_PREFIX, vdev->vbasedev.name); @@ -2801,6 +2845,12 @@ static void vfio_register_req_notifier(VFIOPCIDevice *vdev) fd = event_notifier_get_fd(&vdev->req_notifier); qemu_set_fd_handler(fd, vfio_req_notifier_handler, NULL, vdev); + /* Do not alter irq_signaling during vfio_realize for cpr */ + if (vdev->pdev.reused) { + vdev->req_enabled = true; + return; + } + if (vfio_set_irq_signaling(&vdev->vbasedev, VFIO_PCI_REQ_IRQ_INDEX, 0, VFIO_IRQ_SET_ACTION_TRIGGER, fd, &err)) { error_reportf_err(err, VFIO_MSG_PREFIX, vdev->vbasedev.name); @@ -3330,6 +3380,40 @@ static void vfio_merge_config(VFIOPCIDevice *vdev) } } +static void vfio_claim_vectors(VFIOPCIDevice *vdev, int nr_vectors, bool msix) +{ + int i, fd; + bool pending = false; + PCIDevice *pdev = &vdev->pdev; + + vdev->nr_vectors = nr_vectors; + vdev->msi_vectors = g_new0(VFIOMSIVector, nr_vectors); + vdev->interrupt = msix ? VFIO_INT_MSIX : VFIO_INT_MSI; + + for (i = 0; i < nr_vectors; i++) { + VFIOMSIVector *vector = &vdev->msi_vectors[i]; + + fd = load_event_fd(vdev, "interrupt", i); + if (fd >= 0) { + vfio_vector_init(vdev, i); + qemu_set_fd_handler(fd, vfio_msi_interrupt, NULL, vector); + } + + if (load_event_fd(vdev, "kvm_interrupt", i) >= 0) { + vfio_add_kvm_msi_virq(vdev, vector, i, msix); + } + + if (msix && msix_is_pending(pdev, i) && msix_is_masked(pdev, i)) { + set_bit(i, vdev->msix->pending); + pending = true; + } + } + + if (msix) { + memory_region_set_enabled(&pdev->msix_pba_mmio, pending); + } +} + /* * The kernel may change non-emulated config bits. Exclude them from the * changed-bits check in get_pci_config_device. @@ -3352,9 +3436,24 @@ static int vfio_pci_post_load(void *opaque, int version_id) { VFIOPCIDevice *vdev = opaque; PCIDevice *pdev = &vdev->pdev; + int nr_vectors; vfio_merge_config(vdev); + if (msix_enabled(pdev)) { + nr_vectors = vdev->msix->entries; + vfio_claim_vectors(vdev, nr_vectors, true); + msix_init_vector_notifiers(pdev, vfio_msix_vector_use, + vfio_msix_vector_release, NULL); + + } else if (msi_enabled(pdev)) { + nr_vectors = msi_nr_vectors_allocated(pdev); + vfio_claim_vectors(vdev, nr_vectors, false); + + } else if (vfio_pci_read_config(pdev, PCI_INTERRUPT_PIN, 1)) { + assert(0); /* completed in a subsequent patch */ + } + pdev->reused = false; return 0; @@ -3374,6 +3473,8 @@ static const VMStateDescription vfio_pci_vmstate = { .post_load = vfio_pci_post_load, .needed = vfio_pci_needed, .fields = (VMStateField[]) { + VMSTATE_PCI_DEVICE(pdev, VFIOPCIDevice), + VMSTATE_MSIX_TEST(pdev, VFIOPCIDevice, vfio_msix_present), VMSTATE_END_OF_LIST() } }; -- 1.8.3.1