| Message ID | 1362208619-5028-3-git-send-email-vijaymohan.pandarathil@hp.com |
|---|---|
| State | New |
| Headers | show |
On Sat, 2013-03-02 at 01:16 -0600, Vijay Mohan Pandarathil wrote: > - New VFIO_SET_IRQ ioctl option 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@hp.com> > --- > drivers/vfio/pci/vfio_pci.c | 44 ++++++++++++++++++++++++++++++++- > drivers/vfio/pci/vfio_pci_intrs.c | 49 +++++++++++++++++++++++++++++++++++++ > drivers/vfio/pci/vfio_pci_private.h | 1 + > include/uapi/linux/vfio.h | 1 + > 4 files changed, 94 insertions(+), 1 deletion(-) > > diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c > index 8189cb6..acfcb1a 100644 > --- a/drivers/vfio/pci/vfio_pci.c > +++ b/drivers/vfio/pci/vfio_pci.c > @@ -201,7 +201,9 @@ static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type) > > return (flags & PCI_MSIX_FLAGS_QSIZE) + 1; > } > - } > + } else if (irq_type == VFIO_PCI_ERR_IRQ_INDEX) > + if (pci_is_pcie(vdev->pdev)) > + return 1; > > return 0; > } > @@ -317,6 +319,17 @@ static long vfio_pci_ioctl(void *device_data, > if (info.argsz < minsz || info.index >= VFIO_PCI_NUM_IRQS) > return -EINVAL; > > + switch (info.index) { > + case VFIO_PCI_INTX_IRQ_INDEX ... VFIO_PCI_MSIX_IRQ_INDEX: > + break; > + case VFIO_PCI_ERR_IRQ_INDEX: > + if (pci_is_pcie(vdev->pdev)) > + break; > + /* pass thru to return error */ > + default: > + return -EINVAL; > + } > + > info.flags = VFIO_IRQ_INFO_EVENTFD; > > info.count = vfio_pci_get_irq_count(vdev, info.index); > @@ -551,11 +564,40 @@ static void vfio_pci_remove(struct pci_dev *pdev) > kfree(vdev); > } > > +static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev, > + pci_channel_state_t state) > +{ > + struct vfio_pci_device *vdev; > + struct vfio_device *device; > + > + device = vfio_device_get_from_dev(&pdev->dev); > + if (device == NULL) > + return PCI_ERS_RESULT_DISCONNECT; > + > + vdev = vfio_device_data(device); > + if (vdev == NULL) { > + vfio_device_put(device); > + return PCI_ERS_RESULT_DISCONNECT; > + } > + > + if (vdev->err_trigger) > + eventfd_signal(vdev->err_trigger, 1); > + > + vfio_device_put(device); > + > + return PCI_ERS_RESULT_CAN_RECOVER; > +} > + > +static struct pci_error_handlers vfio_err_handlers = { > + .error_detected = vfio_pci_aer_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_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c > index 3639371..4a29830 100644 > --- a/drivers/vfio/pci/vfio_pci_intrs.c > +++ b/drivers/vfio/pci/vfio_pci_intrs.c > @@ -745,6 +745,48 @@ static int vfio_pci_set_msi_trigger(struct vfio_pci_device *vdev, > return 0; > } > > +static int vfio_pci_set_err_trigger(struct vfio_pci_device *vdev, > + unsigned index, unsigned start, > + unsigned count, uint32_t flags, void *data) > +{ > + int32_t fd = *(int32_t *)data; > + > + if ((index != VFIO_PCI_ERR_IRQ_INDEX) || > + !(flags & VFIO_IRQ_SET_DATA_TYPE_MASK)) > + return -EINVAL; > + > + /* DATA_NONE/DATA_BOOL enables loopback testing */ > + > + if (flags & VFIO_IRQ_SET_DATA_NONE) { > + if (vdev->err_trigger) > + eventfd_signal(vdev->err_trigger, 1); > + return 0; > + } else if (flags & VFIO_IRQ_SET_DATA_BOOL) { > + uint8_t trigger = *(uint8_t *)data; > + if (trigger && vdev->err_trigger) > + eventfd_signal(vdev->err_trigger, 1); > + return 0; > + } > + > + /* Handle SET_DATA_EVENTFD */ > + > + if (fd == -1) { > + if (vdev->err_trigger) > + eventfd_ctx_put(vdev->err_trigger); I mentioned ordering/locking issues back on v3 and I don't think they've been addressed yet. What happens if error_detected is called here? > + vdev->err_trigger = NULL; > + return 0; > + } else if (fd >= 0) { > + struct eventfd_ctx *efdctx; > + efdctx = eventfd_ctx_fdget(fd); > + if (IS_ERR(efdctx)) > + return PTR_ERR(efdctx); > + if (vdev->err_trigger) > + eventfd_ctx_put(vdev->err_trigger); Or here? Both are brief windows where vdev->err_trigger is neither NULL nor valid. The other trigger setup functions do a 1) disable, 2) re-enable where the disable is synchronous and avoids this race. I don't know if you have that capability, so we have to assume that error_detected can be called at any time. I notice that report_error_detected() wraps the callback in a device_lock(), so you could potentially use device_lock/unlock here to avoid racing it. Thanks, Alex > + vdev->err_trigger = efdctx; > + return 0; > + } else > + return -EINVAL; > +} > int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev, uint32_t flags, > unsigned index, unsigned start, unsigned count, > void *data) > @@ -779,6 +821,13 @@ int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev, uint32_t flags, > break; > } > break; > + case VFIO_PCI_ERR_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_err_trigger; > + break; > + } > } > > if (!func) > diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h > index d7e55d0..9c6d5d0 100644 > --- a/drivers/vfio/pci/vfio_pci_private.h > +++ b/drivers/vfio/pci/vfio_pci_private.h > @@ -56,6 +56,7 @@ struct vfio_pci_device { > bool has_vga; > 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/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h > index 4f41f30..284ff24 100644 > --- a/include/uapi/linux/vfio.h > +++ b/include/uapi/linux/vfio.h > @@ -319,6 +319,7 @@ 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 > }; >
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index 8189cb6..acfcb1a 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -201,7 +201,9 @@ static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type) return (flags & PCI_MSIX_FLAGS_QSIZE) + 1; } - } + } else if (irq_type == VFIO_PCI_ERR_IRQ_INDEX) + if (pci_is_pcie(vdev->pdev)) + return 1; return 0; } @@ -317,6 +319,17 @@ static long vfio_pci_ioctl(void *device_data, if (info.argsz < minsz || info.index >= VFIO_PCI_NUM_IRQS) return -EINVAL; + switch (info.index) { + case VFIO_PCI_INTX_IRQ_INDEX ... VFIO_PCI_MSIX_IRQ_INDEX: + break; + case VFIO_PCI_ERR_IRQ_INDEX: + if (pci_is_pcie(vdev->pdev)) + break; + /* pass thru to return error */ + default: + return -EINVAL; + } + info.flags = VFIO_IRQ_INFO_EVENTFD; info.count = vfio_pci_get_irq_count(vdev, info.index); @@ -551,11 +564,40 @@ static void vfio_pci_remove(struct pci_dev *pdev) kfree(vdev); } +static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev, + pci_channel_state_t state) +{ + struct vfio_pci_device *vdev; + struct vfio_device *device; + + device = vfio_device_get_from_dev(&pdev->dev); + if (device == NULL) + return PCI_ERS_RESULT_DISCONNECT; + + vdev = vfio_device_data(device); + if (vdev == NULL) { + vfio_device_put(device); + return PCI_ERS_RESULT_DISCONNECT; + } + + if (vdev->err_trigger) + eventfd_signal(vdev->err_trigger, 1); + + vfio_device_put(device); + + return PCI_ERS_RESULT_CAN_RECOVER; +} + +static struct pci_error_handlers vfio_err_handlers = { + .error_detected = vfio_pci_aer_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_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c index 3639371..4a29830 100644 --- a/drivers/vfio/pci/vfio_pci_intrs.c +++ b/drivers/vfio/pci/vfio_pci_intrs.c @@ -745,6 +745,48 @@ static int vfio_pci_set_msi_trigger(struct vfio_pci_device *vdev, return 0; } +static int vfio_pci_set_err_trigger(struct vfio_pci_device *vdev, + unsigned index, unsigned start, + unsigned count, uint32_t flags, void *data) +{ + int32_t fd = *(int32_t *)data; + + if ((index != VFIO_PCI_ERR_IRQ_INDEX) || + !(flags & VFIO_IRQ_SET_DATA_TYPE_MASK)) + return -EINVAL; + + /* DATA_NONE/DATA_BOOL enables loopback testing */ + + if (flags & VFIO_IRQ_SET_DATA_NONE) { + if (vdev->err_trigger) + eventfd_signal(vdev->err_trigger, 1); + return 0; + } else if (flags & VFIO_IRQ_SET_DATA_BOOL) { + uint8_t trigger = *(uint8_t *)data; + if (trigger && vdev->err_trigger) + eventfd_signal(vdev->err_trigger, 1); + return 0; + } + + /* Handle SET_DATA_EVENTFD */ + + if (fd == -1) { + if (vdev->err_trigger) + eventfd_ctx_put(vdev->err_trigger); + vdev->err_trigger = NULL; + return 0; + } else if (fd >= 0) { + struct eventfd_ctx *efdctx; + efdctx = eventfd_ctx_fdget(fd); + if (IS_ERR(efdctx)) + return PTR_ERR(efdctx); + if (vdev->err_trigger) + eventfd_ctx_put(vdev->err_trigger); + vdev->err_trigger = efdctx; + return 0; + } else + return -EINVAL; +} int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev, uint32_t flags, unsigned index, unsigned start, unsigned count, void *data) @@ -779,6 +821,13 @@ int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev, uint32_t flags, break; } break; + case VFIO_PCI_ERR_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_err_trigger; + break; + } } if (!func) diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h index d7e55d0..9c6d5d0 100644 --- a/drivers/vfio/pci/vfio_pci_private.h +++ b/drivers/vfio/pci/vfio_pci_private.h @@ -56,6 +56,7 @@ struct vfio_pci_device { bool has_vga; 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/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 4f41f30..284ff24 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -319,6 +319,7 @@ 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 };
- New VFIO_SET_IRQ ioctl option 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@hp.com> --- drivers/vfio/pci/vfio_pci.c | 44 ++++++++++++++++++++++++++++++++- drivers/vfio/pci/vfio_pci_intrs.c | 49 +++++++++++++++++++++++++++++++++++++ drivers/vfio/pci/vfio_pci_private.h | 1 + include/uapi/linux/vfio.h | 1 + 4 files changed, 94 insertions(+), 1 deletion(-)