[PATCH v2 3/3] QEMU-AER: Qemu changes to support AER for VFIO-PCIdevices
From: Pandarathil, Vijaymohan R
Date: Mon Jan 28 2013 - 04:55:12 EST
- Create eventfd per vfio device assigned to a guest and register an
event handler
- This fd is passed to the vfio_pci driver through the SET_IRQ ioctl
- When the device encounters an error, the eventfd is signalled
and the qemu eventfd handler gets invoked.
- In the handler decide what action to take. Current action taken
is to terminate the guest.
Signed-off-by: Vijay Mohan Pandarathil <vijaymohan.pandarathil@xxxxxx>
---
hw/vfio_pci.c | 106 +++++++++++++++++++++++++++++++++++++++++++++
linux-headers/linux/vfio.h | 3 ++
2 files changed, 109 insertions(+)
diff --git a/hw/vfio_pci.c b/hw/vfio_pci.c
index c51ae67..c4a6aec 100644
--- a/hw/vfio_pci.c
+++ b/hw/vfio_pci.c
@@ -130,6 +130,8 @@ typedef struct VFIODevice {
QLIST_ENTRY(VFIODevice) next;
struct VFIOGroup *group;
bool reset_works;
+ bool pci_aer_notify_cap;
+ EventNotifier err_notifier;
} VFIODevice;
typedef struct VFIOGroup {
@@ -1837,6 +1839,10 @@ static int vfio_get_device(VFIOGroup *group, const char *name, VFIODevice *vdev)
error_report("Warning, device %s does not support reset\n", name);
}
+ vdev->pci_aer_notify_cap = !!(dev_info.flags &
+ (VFIO_DEVICE_FLAGS_PCI_AER |
+ VFIO_DEVICE_FLAGS_PCI_AER_NOTIFY));
+
if (dev_info.num_regions < VFIO_PCI_CONFIG_REGION_INDEX + 1) {
error_report("vfio: unexpected number of io regions %u\n",
dev_info.num_regions);
@@ -1922,6 +1928,103 @@ static void vfio_put_device(VFIODevice *vdev)
}
}
+static void vfio_err_notifier_handler(void *opaque)
+{
+ VFIODevice *vdev = opaque;
+
+ if (!event_notifier_test_and_clear(&vdev->err_notifier)) {
+ return;
+ }
+
+ /*
+ * TBD. Retrieve the error details and decide what action
+ * needs to be taken. One of the actions could be to pass
+ * the error to the guest and have the guest driver recover
+ * from the error. This requires that PCIe capabilities be
+ * exposed to the guest. At present, we just terminate the
+ * guest to contain the error.
+ */
+
+ error_report("%s (%04x:%02x:%02x.%x)"
+ "Unrecoverable error detected... Terminating guest\n",
+ __func__, vdev->host.domain, vdev->host.bus,
+ vdev->host.slot, vdev->host.function);
+
+ hw_error("(%04x:%02x:%02x.%x) Unrecoverable device error\n",
+ vdev->host.domain, vdev->host.bus,
+ vdev->host.slot, vdev->host.function);
+
+ return;
+}
+
+static void vfio_register_err_notifier(VFIODevice *vdev)
+{
+ int ret;
+ int argsz;
+ struct vfio_irq_set *irq_set;
+ int32_t *pfd;
+
+ if (!(vdev->pci_aer_notify_cap)) {
+ DPRINTF("vfio: Error notification not supported for the device\n");
+ return;
+ }
+ if (event_notifier_init(&vdev->err_notifier, 0)) {
+ error_report("vfio: Warning: Unable to init event notifier for error detection\n");
+ return;
+ }
+
+ argsz = sizeof(*irq_set) + sizeof(*pfd);
+
+ irq_set = g_malloc0(argsz);
+ irq_set->argsz = argsz;
+ irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD |
+ VFIO_IRQ_SET_ACTION_TRIGGER;
+ irq_set->index = VFIO_PCI_ERR_IRQ_INDEX;
+ irq_set->start = 0;
+ irq_set->count = 1;
+ pfd = (int32_t *)&irq_set->data;
+
+ *pfd = event_notifier_get_fd(&vdev->err_notifier);
+ qemu_set_fd_handler(*pfd, vfio_err_notifier_handler, NULL, vdev);
+
+ ret = ioctl(vdev->fd, VFIO_DEVICE_SET_IRQS, irq_set);
+ if (ret) {
+ error_report("vfio: Warning: Failed to setup error fd: %d\n", ret);
+ qemu_set_fd_handler(*pfd, NULL, NULL, vdev);
+ event_notifier_cleanup(&vdev->err_notifier);
+ }
+ g_free(irq_set);
+ return;
+}
+static void vfio_unregister_err_notifier(VFIODevice *vdev)
+{
+ int argsz;
+ struct vfio_irq_set *irq_set;
+ int32_t *pfd;
+ int ret;
+
+ argsz = sizeof(*irq_set) + sizeof(*pfd);
+
+ irq_set = g_malloc0(argsz);
+ irq_set->argsz = argsz;
+ irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD |
+ VFIO_IRQ_SET_ACTION_TRIGGER;
+ irq_set->index = VFIO_PCI_ERR_IRQ_INDEX;
+ irq_set->start = 0;
+ irq_set->count = 1;
+ pfd = (int32_t *)&irq_set->data;
+ *pfd = -1;
+
+ ret = ioctl(vdev->fd, VFIO_DEVICE_SET_IRQS, irq_set);
+ if (ret) {
+ DPRINTF("vfio: Failed to de-assign error fd: %d\n", ret);
+ }
+ g_free(irq_set);
+ qemu_set_fd_handler(event_notifier_get_fd(&vdev->err_notifier),
+ NULL, NULL, vdev);
+ event_notifier_cleanup(&vdev->err_notifier);
+ return;
+}
static int vfio_initfn(PCIDevice *pdev)
{
VFIODevice *pvdev, *vdev = DO_UPCAST(VFIODevice, pdev, pdev);
@@ -2032,6 +2135,8 @@ static int vfio_initfn(PCIDevice *pdev)
}
}
+ vfio_register_err_notifier(vdev);
+
return 0;
out_teardown:
@@ -2049,6 +2154,7 @@ static void vfio_exitfn(PCIDevice *pdev)
VFIODevice *vdev = DO_UPCAST(VFIODevice, pdev, pdev);
VFIOGroup *group = vdev->group;
+ vfio_unregister_err_notifier(vdev);
pci_device_set_intx_routing_notifier(&vdev->pdev, NULL);
vfio_disable_interrupts(vdev);
if (vdev->intx.mmap_timer) {
diff --git a/linux-headers/linux/vfio.h b/linux-headers/linux/vfio.h
index f787b72..ed87792 100644
--- a/linux-headers/linux/vfio.h
+++ b/linux-headers/linux/vfio.h
@@ -147,6 +147,8 @@ struct vfio_device_info {
__u32 flags;
#define VFIO_DEVICE_FLAGS_RESET (1 << 0) /* Device supports reset */
#define VFIO_DEVICE_FLAGS_PCI (1 << 1) /* vfio-pci device */
+#define VFIO_DEVICE_FLAGS_PCI_AER (1 << 2) /* AER capable */
+#define VFIO_DEVICE_FLAGS_PCI_AER_NOTIFY (1 << 3) /* Supports aer notify */
__u32 num_regions; /* Max region index + 1 */
__u32 num_irqs; /* Max IRQ index + 1 */
};
@@ -310,6 +312,7 @@ enum {
VFIO_PCI_INTX_IRQ_INDEX,
VFIO_PCI_MSI_IRQ_INDEX,
VFIO_PCI_MSIX_IRQ_INDEX,
+ VFIO_PCI_ERR_IRQ_INDEX,
VFIO_PCI_NUM_IRQS
};
--
1.7.11.3
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