On Wed, 2013-01-09 at 06:26 +0000, Pandarathil, Vijaymohan R wrote: > - New ioctl which is used to pass the eventfd that is signaled when > an error occurs in the vfio_pci_device > > - Register pci_error_handler for the vfio_pci driver > > - When the device encounters an error, the error handler registered by > the vfio_pci driver gets invoked by the AER infrastructure > > - In the error handler, signal the eventfd registered for the device. > > - This results in the qemu eventfd handler getting invoked and > appropriate action taken for the guest. > > Signed-off-by: Vijay Mohan Pandarathil <vijaymohan.pandarathil@xxxxxx> > --- > drivers/vfio/pci/vfio_pci.c | 29 +++++++++++++++++++++++++++++ > drivers/vfio/pci/vfio_pci_private.h | 1 + > drivers/vfio/vfio.c | 8 ++++++++ > include/linux/vfio.h | 1 + > include/uapi/linux/vfio.h | 9 +++++++++ > 5 files changed, 48 insertions(+) > > diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c > index 6c11994..4ae9526 100644 > --- a/drivers/vfio/pci/vfio_pci.c > +++ b/drivers/vfio/pci/vfio_pci.c > @@ -207,6 +207,8 @@ static long vfio_pci_ioctl(void *device_data, > if (vdev->reset_works) > info.flags |= VFIO_DEVICE_FLAGS_RESET; > > + info.flags |= VFIO_DEVICE_FLAGS_AER_NOTIFY; > + This appears to be a PCI specific flag, so the name should include _PCI_. We also support non-PCIe devices and it seems like it would be possible to not have AER support available, so shouldn't this be conditional? > info.num_regions = VFIO_PCI_NUM_REGIONS; > info.num_irqs = VFIO_PCI_NUM_IRQS; > > @@ -348,6 +350,19 @@ static long vfio_pci_ioctl(void *device_data, > > return ret; > > + } else if (cmd == VFIO_DEVICE_SET_ERRFD) { > + int32_t fd = (int32_t)arg; > + > + if (fd < 0) > + return -EINVAL; > + > + vdev->err_trigger = eventfd_ctx_fdget(fd); > + > + if (IS_ERR(vdev->err_trigger)) > + return PTR_ERR(vdev->err_trigger); > + > + return 0; > + I'm not sure why we wouldn't describe this as just another interrupt from the device and configure it via SET_IRQ. This ioctl has very limited use and doesn't follow any of the conventions of all the other vfio ioctls. > } else if (cmd == VFIO_DEVICE_RESET) > return vdev->reset_works ? > pci_reset_function(vdev->pdev) : -EINVAL; > @@ -527,11 +542,25 @@ static void vfio_pci_remove(struct pci_dev *pdev) > kfree(vdev); > } > > +static pci_ers_result_t vfio_err_detected(struct pci_dev *pdev, > + pci_channel_state_t state) > +{ > + struct vfio_pci_device *vdev = vfio_get_vdev(&pdev->dev); > + > + eventfd_signal(vdev->err_trigger, 1); > + return PCI_ERS_RESULT_CAN_RECOVER; > +} What if err_trigger hasn't been set? > + > +static const struct pci_error_handlers vfio_err_handlers = { > + .error_detected = vfio_err_detected, > +}; > + > static struct pci_driver vfio_pci_driver = { > .name = "vfio-pci", > .id_table = NULL, /* only dynamic ids */ > .probe = vfio_pci_probe, > .remove = vfio_pci_remove, > + .err_handler = &vfio_err_handlers, > }; > > static void __exit vfio_pci_cleanup(void) > diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h > index 611827c..daee62f 100644 > --- a/drivers/vfio/pci/vfio_pci_private.h > +++ b/drivers/vfio/pci/vfio_pci_private.h > @@ -55,6 +55,7 @@ struct vfio_pci_device { > bool bardirty; > struct pci_saved_state *pci_saved_state; > atomic_t refcnt; > + struct eventfd_ctx *err_trigger; > }; > > #define is_intx(vdev) (vdev->irq_type == VFIO_PCI_INTX_IRQ_INDEX) > diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c > index 56097c6..5ed5a54 100644 > --- a/drivers/vfio/vfio.c > +++ b/drivers/vfio/vfio.c > @@ -693,6 +693,14 @@ void *vfio_del_group_dev(struct device *dev) > } > EXPORT_SYMBOL_GPL(vfio_del_group_dev); > > +void *vfio_get_vdev(struct device *dev) > +{ > + struct vfio_device *device = dev_get_drvdata(dev); > + > + return device->device_data; > +} > +EXPORT_SYMBOL_GPL(vfio_get_vdev); > + This is unsafe. How do we know dev is a vfio device? How do we keep that drvdata valid while you're using it? I think you want to export the existing vfio_group_get_device() and vfio_device_put(). Thanks, Alex > /** > * VFIO base fd, /dev/vfio/vfio > */ > diff --git a/include/linux/vfio.h b/include/linux/vfio.h > index ab9e862..3c97b03 100644 > --- a/include/linux/vfio.h > +++ b/include/linux/vfio.h > @@ -45,6 +45,7 @@ extern int vfio_add_group_dev(struct device *dev, > void *device_data); > > extern void *vfio_del_group_dev(struct device *dev); > +extern void *vfio_get_vdev(struct device *dev); > > /** > * struct vfio_iommu_driver_ops - VFIO IOMMU driver callbacks > diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h > index 4758d1b..fa67213 100644 > --- a/include/uapi/linux/vfio.h > +++ b/include/uapi/linux/vfio.h > @@ -147,6 +147,7 @@ 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_AER_NOTIFY (1 << 2) /* Supports aer notify */ > __u32 num_regions; /* Max region index + 1 */ > __u32 num_irqs; /* Max IRQ index + 1 */ > }; > @@ -288,6 +289,14 @@ struct vfio_irq_set { > */ > #define VFIO_DEVICE_RESET _IO(VFIO_TYPE, VFIO_BASE + 11) > > +/** > + * VFIO_DEVICE_SET_ERRFD - _IO(VFIO_TYPE, VFIO_BASE + 12) > + * > + * Pass the eventfd to the vfio-pci driver for signalling any device > + * error notifications > + */ > +#define VFIO_DEVICE_SET_ERRFD _IO(VFIO_TYPE, VFIO_BASE + 12) > + > /* > * The VFIO-PCI bus driver makes use of the following fixed region and > * IRQ index mapping. Unimplemented regions return a size of zero. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html