[Qemu-devel] [RFC v7 04/11] vfio: add check host bus reset is support or not

[Chen Fan]

when machine is done, we should check the all vfio devices
whether support host bus reset, then when need virtual secondary
bus reset, we should reset host bus.

Signed-off-by: Chen Fan <address@hidden>
---
 hw/vfio/pci.c | 83 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 83 insertions(+)

diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 43869e9..ff639db 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -168,6 +168,7 @@ typedef struct VFIOPCIDevice {
     bool req_enabled;
     bool has_flr;
     bool has_pm_reset;
+    bool has_bus_reset;
     bool rom_read_failed;
 } VFIOPCIDevice;
 
@@ -3533,6 +3534,82 @@ static void vfio_pci_host_needs_bus_reset(Notifier *n, 
void *opaque)
     vbasedev->needs_bus_reset = true;
 }
 
+static void vfio_check_host_bus_reset(VFIODevice *vbasedev)
+{
+    VFIOPCIDevice *vdev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
+    struct vfio_pci_hot_reset_info *info = NULL;
+    struct vfio_pci_dependent_device *devices;
+    VFIOGroup *group;
+    int ret, i;
+
+    ret = vfio_get_hot_reset_info(vdev, &info);
+    if (ret < 0) {
+        goto out;
+    }
+
+    devices = &info->devices[0];
+
+    /* Verify that we have all the groups required */
+    for (i = 0; i < info->count; i++) {
+        PCIHostDeviceAddress host;
+        VFIOPCIDevice *tmp;
+        VFIODevice *vbasedev_iter;
+
+        host.domain = devices[i].segment;
+        host.bus = devices[i].bus;
+        host.slot = PCI_SLOT(devices[i].devfn);
+        host.function = PCI_FUNC(devices[i].devfn);
+
+        if (vfio_pci_host_match(&host, &vdev->host)) {
+            continue;
+        }
+
+        QLIST_FOREACH(group, &vfio_group_list, next) {
+            if (group->groupid == devices[i].group_id) {
+                break;
+            }
+        }
+
+        if (!group) {
+            goto out;
+        }
+
+        QLIST_FOREACH(vbasedev_iter, &group->device_list, next) {
+            if (vbasedev_iter->type != VFIO_DEVICE_TYPE_PCI) {
+                continue;
+            }
+            tmp = container_of(vbasedev_iter, VFIOPCIDevice, vbasedev);
+            if (vfio_pci_host_match(&host, &tmp->host)) {
+                if (PCI_BUS(vdev->pdev.bus) !=
+                    PCI_BUS(tmp->pdev.bus)) {
+                    goto out;
+                }
+            }
+        }
+    }
+
+    vdev->has_bus_reset = true;
+
+out:
+    g_free(info);
+}
+
+static void vfio_pci_machine_done_notify(Notifier *notifier, void *unused)
+{
+    VFIOGroup *group;
+    VFIODevice *vbasedev;
+
+    QLIST_FOREACH(group, &vfio_group_list, next) {
+         QLIST_FOREACH(vbasedev, &group->device_list, next) {
+             vfio_check_host_bus_reset(vbasedev);
+         }
+    }
+}
+
+static Notifier machine_notifier = {
+    .notify = vfio_pci_machine_done_notify,
+};
+
 static int vfio_initfn(PCIDevice *pdev)
 {
     VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev);
@@ -3821,6 +3898,12 @@ static const TypeInfo vfio_pci_dev_info = {
 static void register_vfio_pci_dev_type(void)
 {
     type_register_static(&vfio_pci_dev_info);
+
+    /*
+     * Register notifier when machine init is done, since we need
+     * check the configration manner after all vfio device are inited.
+     */
+    qemu_add_machine_init_done_notifier(&machine_notifier);
 }
 
 type_init(register_vfio_pci_dev_type)
-- 
1.9.3