On 03/22/2016 05:40 AM, Alex Williamson wrote:
On Mon, 21 Mar 2016 18:08:44 +0800
Cao jin <caoj.f...@cn.fujitsu.com> wrote:
From: Chen Fan <chen.fan.f...@cn.fujitsu.com>
Due to all devices assigned to VM on the same way as host if enable
aer, so we can easily do the hot reset by selecting the function #0
to do the hot reset.
Signed-off-by: Chen Fan <chen.fan.f...@cn.fujitsu.com>
---
hw/vfio/pci.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
hw/vfio/pci.h | 2 ++
2 files changed, 52 insertions(+)
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 9902c87..718cde7 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -1900,6 +1900,8 @@ static void vfio_check_hot_bus_reset(VFIOPCIDevice *vdev,
Error **errp)
/* List all affected devices by bus reset */
devices = &info->devices[0];
+ vdev->single_depend_dev = (info->count == 1);
+
/* Verify that we have all the groups required */
for (i = 0; i < info->count; i++) {
PCIHostDeviceAddress host;
@@ -2608,11 +2610,36 @@ static void vfio_put_device(VFIOPCIDevice *vdev)
static void vfio_err_notifier_handler(void *opaque)
{
VFIOPCIDevice *vdev = opaque;
+ PCIDevice *pdev = &vdev->pdev;
if (!event_notifier_test_and_clear(&vdev->err_notifier)) {
return;
}
+ if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
+ VFIOPCIDevice *tmp;
+ PCIDevice *dev;
+ int devfn;
+
+ /*
+ * If one device has aer capability on a bus, when aer occurred,
+ * we should notify all devices on the bus there was an aer arrived,
+ * then we are able to vote the device #0 to do host bus reset.
+ */
+ for (devfn = 0; devfn < 8; devfn++) {
ARI?
+ dev = pci_find_device(pdev->bus, pci_bus_num(pdev->bus),
+ PCI_DEVFN(PCI_SLOT(pdev->devfn), devfn));
+ if (!dev) {
+ continue;
+ }
+ if (!object_dynamic_cast(OBJECT(dev), "vfio-pci")) {
+ continue;
+ }
+ tmp = DO_UPCAST(VFIOPCIDevice, pdev, dev);
+ tmp->aer_occurred = true;
+ }
+ }
+
/*
* TBD. Retrieve the error details and decide what action
* needs to be taken. One of the actions could be to pass
@@ -3075,6 +3102,29 @@ static void vfio_pci_reset(DeviceState *dev)
trace_vfio_pci_reset(vdev->vbasedev.name);
+ if (vdev->aer_occurred) {
+ PCIDevice *br = pci_bridge_get_device(pdev->bus);
+
+ if (br &&
+ (pci_get_word(br->config + PCI_BRIDGE_CONTROL) &
+ PCI_BRIDGE_CTL_BUS_RESET)) {
+ /* simply voting the function 0 to do hot bus reset */
+ if (pci_get_function_0(pdev) == pdev) {
+ if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
+ vfio_pci_hot_reset(vdev, vdev->single_depend_dev);
+ } else {
+ /* if this device has not AER capability, code
+ * coming here indicates there is another function
+ * on the bus has AER capability.
+ * */
This shouldn't be possible, right?
+ vfio_pci_hot_reset(vdev, false);
+ }
+ }
+ vdev->aer_occurred = false;
+ return;
+ }
+ }
Why do we care than an AER occurred now? Can't we simply test:
if (vdev->features & VFIO_FEATURE_ENABLE_AER &&
pci_get_function_0(pdev) == pdev) {
PCIDevice *br = pci_bridge_get_device(pdev->bus);
if (pci_get_word(br->config + PCI_BRIDGE_CONTROL) &
PCI_BRIDGE_CTL_BUS_RESET)) {
vfio_pci_hot_reset(vdev, vdev->single_depend_dev);
return;
}
}
do we have the case that only one/few of the devices affected
by a bus reset assigned to VM enabled AER, then when bus
reset, we let the function 0 do hot reset, which may not enable AER,
but we should tell other devices on the bus that they don't need
to do bus reset. so I just mark all devices on the bus when needing a
hot reset.
Thanks,
Chen
+
vfio_pci_pre_reset(vdev);
if (vdev->resetfn && !vdev->resetfn(vdev)) {
diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
index db7c6d5..17c75b8 100644
--- a/hw/vfio/pci.h
+++ b/hw/vfio/pci.h
@@ -143,6 +143,8 @@ typedef struct VFIOPCIDevice {
bool no_kvm_intx;
bool no_kvm_msi;
bool no_kvm_msix;
+ bool aer_occurred;
+ bool single_depend_dev;
} VFIOPCIDevice;
uint32_t vfio_pci_read_config(PCIDevice *pdev, uint32_t addr, int len);
.
