[PATCH] vfio-pci: report recovery event after device recovery successful

Hogan Wang
2022-04-20T07:16:11Z

As you all know, device faults are classified into the following
types: unrecoverable error and recoverable error. vfio-pci drvier
will report error event to user-space process while device occur
hardware errors, and still report the other error event after deivce
recovery successful. So the user-space process just like qemu can not
identify the event is an hardware error event or a device recovery
successful event. So in order to solve this problem, add an eventfd
named recov_trigger to report device recovery successful event, the
user-space process can make a decision whether to process the recovery
event or not.

Signed-off-by: Hogan Wang <hogan.wang@huawei.com>
---
drivers/vfio/pci/vfio_pci_core.c | 13 +++++++++++--
drivers/vfio/pci/vfio_pci_intrs.c | 19 +++++++++++++++++++
include/linux/vfio_pci_core.h | 1 +
include/uapi/linux/vfio.h | 1 +
4 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
index b7bb16f92ac6..2360cb44aa36 100644
--- a/drivers/vfio/pci/vfio_pci_core.c
+++ b/drivers/vfio/pci/vfio_pci_core.c
@@ -483,6 +483,10 @@ void vfio_pci_core_close_device(struct vfio_device *core_vdev)
eventfd_ctx_put(vdev->err_trigger);
vdev->err_trigger = NULL;
}
+ if (vdev->recov_trigger) {
+ eventfd_ctx_put(vdev->recov_trigger);
+ vdev->recov_trigger = NULL;
+ }
if (vdev->req_trigger) {
eventfd_ctx_put(vdev->req_trigger);
vdev->req_trigger = NULL;
@@ -1922,8 +1926,13 @@ pci_ers_result_t vfio_pci_core_aer_err_detected(struct pci_dev *pdev,

mutex_lock(&vdev->igate);

- if (vdev->err_trigger)
- eventfd_signal(vdev->err_trigger, 1);
+ if (state == pci_channel_io_normal) {
+ if (vdev->recov_trigger)
+ eventfd_signal(vdev->recov_trigger, 1);
+ } else {
+ if (vdev->err_trigger)
+ eventfd_signal(vdev->err_trigger, 1);
+ }

mutex_unlock(&vdev->igate);

diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c
index 6069a11fb51a..be76ff76c361 100644
--- a/drivers/vfio/pci/vfio_pci_intrs.c
+++ b/drivers/vfio/pci/vfio_pci_intrs.c
@@ -624,6 +624,17 @@ static int vfio_pci_set_err_trigger(struct vfio_pci_core_device *vdev,
count, flags, data);
}

+static int vfio_pci_set_recov_trigger(struct vfio_pci_core_device *vdev,
+ unsigned index, unsigned start,
+ unsigned count, uint32_t flags, void *data)
+{
+ if (index != VFIO_PCI_ERR_IRQ_INDEX || start != 0 || count > 1)
+ return -EINVAL;
+
+ return vfio_pci_set_ctx_trigger_single(&vdev->recov_trigger,
+ count, flags, data);
+}
+
static int vfio_pci_set_req_trigger(struct vfio_pci_core_device *vdev,
unsigned index, unsigned start,
unsigned count, uint32_t flags, void *data)
@@ -684,6 +695,14 @@ int vfio_pci_set_irqs_ioctl(struct vfio_pci_core_device *vdev, uint32_t flags,
break;
}
break;
+ case VFIO_PCI_RECOV_IRQ_INDEX:
+ switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
+ case VFIO_IRQ_SET_ACTION_TRIGGER:
+ if (pci_is_pcie(vdev->pdev))
+ func = vfio_pci_set_recov_trigger;
+ break;
+ }
+ break;
}

if (!func)
diff --git a/include/linux/vfio_pci_core.h b/include/linux/vfio_pci_core.h
index 74a4a0f17b28..d94addb18118 100644
--- a/include/linux/vfio_pci_core.h
+++ b/include/linux/vfio_pci_core.h
@@ -128,6 +128,7 @@ struct vfio_pci_core_device {
struct pci_saved_state *pm_save;
int ioeventfds_nr;
struct eventfd_ctx *err_trigger;
+ struct eventfd_ctx *recov_trigger;
struct eventfd_ctx *req_trigger;
struct list_head dummy_resources_list;
struct mutex ioeventfds_lock;
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index fea86061b44e..f88a6ca62c49 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -621,6 +621,7 @@ enum {
VFIO_PCI_MSIX_IRQ_INDEX,
VFIO_PCI_ERR_IRQ_INDEX,
VFIO_PCI_REQ_IRQ_INDEX,
+ VFIO_PCI_RECOV_IRQ_INDEX,
VFIO_PCI_NUM_IRQS
};

--
2.33.0