Alex,
Do you have any comments on this version & and the qemu parts?
--
Sincerely,
Cao jin
On 12/31/2016 05:15 PM, Cao jin wrote:
> Support serious device error recovery
>
> Signed-off-by: Cao jin <caoj.fnst@xxxxxxxxxxxxxx>
> ---
> drivers/vfio/pci/vfio_pci.c | 70 +++++++++++++++++++++++++++++++++++--
> drivers/vfio/pci/vfio_pci_private.h | 2 ++
> 2 files changed, 70 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
> index 712a849..752af20 100644
> --- a/drivers/vfio/pci/vfio_pci.c
> +++ b/drivers/vfio/pci/vfio_pci.c
> @@ -534,6 +534,15 @@ static long vfio_pci_ioctl(void *device_data,
> {
> struct vfio_pci_device *vdev = device_data;
> unsigned long minsz;
> + int ret;
> +
> + if (vdev->aer_recovering && (cmd == VFIO_DEVICE_SET_IRQS ||
> + cmd == VFIO_DEVICE_RESET || cmd == VFIO_DEVICE_PCI_HOT_RESET)) {
> + ret = wait_for_completion_interruptible(
> + &vdev->aer_completion);
> + if (ret)
> + return ret;
> + }
>
> if (cmd == VFIO_DEVICE_GET_INFO) {
> struct vfio_device_info info;
> @@ -953,6 +962,15 @@ static ssize_t vfio_pci_rw(void *device_data, char __user *buf,
> {
> unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos);
> struct vfio_pci_device *vdev = device_data;
> + int ret;
> +
> + /* block all kinds of access during host recovery */
> + if (vdev->aer_recovering) {
> + ret = wait_for_completion_interruptible(
> + &vdev->aer_completion);
> + if (ret)
> + return ret;
> + }
>
> if (index >= VFIO_PCI_NUM_REGIONS + vdev->num_regions)
> return -EINVAL;
> @@ -1117,6 +1135,7 @@ static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> vdev->irq_type = VFIO_PCI_NUM_IRQS;
> mutex_init(&vdev->igate);
> spin_lock_init(&vdev->irqlock);
> + init_completion(&vdev->aer_completion);
>
> ret = vfio_add_group_dev(&pdev->dev, &vfio_pci_ops, vdev);
> if (ret) {
> @@ -1176,6 +1195,9 @@ static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev,
> {
> struct vfio_pci_device *vdev;
> struct vfio_device *device;
> + u32 uncor_status;
> + unsigned int aer_cap_offset;
> + int ret;
>
> device = vfio_device_get_from_dev(&pdev->dev);
> if (device == NULL)
> @@ -1187,10 +1209,29 @@ static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev,
> return PCI_ERS_RESULT_DISCONNECT;
> }
>
> + /*
> + * get device's uncorrectable error status as soon as possible,
> + * and signal it to user space. The later we read it, the possibility
> + * the register value is mangled grows.
> + */
> + aer_cap_offset = pci_find_ext_capability(vdev->pdev, PCI_EXT_CAP_ID_ERR);
> + ret = pci_read_config_dword(vdev->pdev, aer_cap_offset +
> + PCI_ERR_UNCOR_STATUS, &uncor_status);
> + if (ret)
> + return PCI_ERS_RESULT_DISCONNECT;
> +
> + pr_info("device %d got AER detect notification. uncorrectable error status = 0x%x\n", pdev->devfn, uncor_status);//to be removed
> mutex_lock(&vdev->igate);
>
> - if (vdev->err_trigger)
> - eventfd_signal(vdev->err_trigger, 1);
> + vdev->aer_recovering = true;
> + reinit_completion(&vdev->aer_completion);
> +
> + if (vdev->err_trigger && uncor_status) {
> + pr_info("device %d signal uncor status 0x%x to user",
> + pdev->devfn, uncor_status);
> + /* signal uncorrectable error status to user space */
> + eventfd_signal(vdev->err_trigger, uncor_status);
> + }
>
> mutex_unlock(&vdev->igate);
>
> @@ -1199,8 +1240,33 @@ static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev,
> return PCI_ERS_RESULT_CAN_RECOVER;
> }
>
> +static void vfio_pci_aer_resume(struct pci_dev *pdev)
> +{
> + struct vfio_pci_device *vdev;
> + struct vfio_device *device;
> +
> + device = vfio_device_get_from_dev(&pdev->dev);
> + if (device == NULL)
> + return;
> +
> + vdev = vfio_device_data(device);
> + if (vdev == NULL) {
> + vfio_device_put(device);
> + return;
> + }
> +
> + mutex_lock(&vdev->igate);
> + vdev->aer_recovering = false;
> + mutex_unlock(&vdev->igate);
> +
> + complete_all(&vdev->aer_completion);
> +
> + vfio_device_put(device);
> +}
> +
> static const struct pci_error_handlers vfio_err_handlers = {
> .error_detected = vfio_pci_aer_err_detected,
> + .resume = vfio_pci_aer_resume,
> };
>
> static struct pci_driver vfio_pci_driver = {
> diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h
> index 8a7d546..ba8471f 100644
> --- a/drivers/vfio/pci/vfio_pci_private.h
> +++ b/drivers/vfio/pci/vfio_pci_private.h
> @@ -83,6 +83,8 @@ struct vfio_pci_device {
> bool bardirty;
> bool has_vga;
> bool needs_reset;
> + bool aer_recovering;
> + struct completion aer_completion;
> struct pci_saved_state *pci_saved_state;
> int refcnt;
> struct eventfd_ctx *err_trigger;
>
--
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