Add a notifier calback to parent's ops structure of mdev device so that per
device notifer for vfio module is registered through vfio_mdev module.
Signed-off-by: Kirti Wankhede <kwankh...@nvidia.com>
Signed-off-by: Neo Jia <c...@nvidia.com>
Change-Id: Iafa6f1721aecdd6e50eb93b153b5621e6d29b637
---
drivers/vfio/mdev/vfio_mdev.c | 34 +++++++++++++++++++++++++++++++++-
include/linux/mdev.h | 9 +++++++++
2 files changed, 42 insertions(+), 1 deletion(-)
diff --git a/drivers/vfio/mdev/vfio_mdev.c b/drivers/vfio/mdev/vfio_mdev.c
index ffc36758cb84..2f8e06e5f95a 100644
--- a/drivers/vfio/mdev/vfio_mdev.c
+++ b/drivers/vfio/mdev/vfio_mdev.c
@@ -24,6 +24,15 @@
#define DRIVER_AUTHOR "NVIDIA Corporation"
#define DRIVER_DESC "VFIO based driver for Mediated device"
+static int vfio_mdev_notifier(struct notifier_block *nb, unsigned long action,
+ void *data)
+{
+ struct mdev_device *mdev = container_of(nb, struct mdev_device, nb);
+ struct parent_device *parent = mdev->parent;
+
+ return parent->ops->notifier(mdev, action, data);
+}
+
static int vfio_mdev_open(void *device_data)
{
struct mdev_device *mdev = device_data;
@@ -36,9 +45,27 @@ static int vfio_mdev_open(void *device_data)
if (!try_module_get(THIS_MODULE))
return -ENODEV;
+ if (likely(parent->ops->notifier)) {
+ mdev->nb.notifier_call = vfio_mdev_notifier;
+ ret = vfio_register_notifier(&mdev->dev, &mdev->nb);
+
+ /*
+ * This should not fail if backend iommu module doesn't support
+ * register_notifier.
+ */
+ if (ret && (ret != -ENOTTY)) {
+ pr_err("Failed to register notifier for mdev\n");
+ module_put(THIS_MODULE);
+ return ret;
+ }
+ }
+
ret = parent->ops->open(mdev);
- if (ret)
+ if (ret) {
+ if (likely(parent->ops->notifier))
+ vfio_unregister_notifier(&mdev->dev, &mdev->nb);
module_put(THIS_MODULE);
+ }
return ret;
}
@@ -51,6 +78,11 @@ static void vfio_mdev_release(void *device_data)
if (likely(parent->ops->release))
parent->ops->release(mdev);
+ if (likely(parent->ops->notifier)) {
+ if (vfio_unregister_notifier(&mdev->dev, &mdev->nb))
+ pr_err("Failed to unregister notifier for mdev\n");
+ }
+
module_put(THIS_MODULE);
}
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index ec819e9a115a..94c43034c297 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -37,6 +37,7 @@ struct mdev_device {
struct kref ref;
struct list_head next;
struct kobject *type_kobj;
+ struct notifier_block nb;
};
/**
@@ -85,6 +86,12 @@ struct mdev_device {
* @mmap: mmap callback
* @mdev: mediated device structure
* @vma: vma structure
+ * @notifer: Notifier callback, currently only for
+ * VFIO_IOMMU_NOTIFY_DMA_UNMAP action notified duing
+ * DMA_UNMAP call on mapped iova range.
+ * @mdev: mediated device structure
+ * @action: Action for which notifier is called
+ * @data: Data associated with the notifier
* Parent device that support mediated device should be registered with mdev
* module with parent_ops structure.
**/
@@ -106,6 +113,8 @@ struct parent_ops {
ssize_t (*ioctl)(struct mdev_device *mdev, unsigned int cmd,
unsigned long arg);
int (*mmap)(struct mdev_device *mdev, struct vm_area_struct *vma);
+ int (*notifier)(struct mdev_device *mdev, unsigned long action,
+ void *data);
};
/* interface for exporting mdev supported type attributes */
--
2.7.0
