[PATCH v3] mdev: Send uevents around parent device registration

[PATCH v3] mdev: Send uevents around parent device registration

[Alex Williamson]

This allows udev to trigger rules when a parent device is registered
or unregistered from mdev.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
---

v3: Add Connie's R-b
    Add comment clarifying expected device requirements for unreg

 drivers/vfio/mdev/mdev_core.c |    9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index ae23151442cb..23976db6c6c7 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -146,6 +146,8 @@ int mdev_register_device(struct device *dev, const struct mdev_parent_ops *ops)
 {
 	int ret;
 	struct mdev_parent *parent;
+	char *env_string = "MDEV_STATE=registered";
+	char *envp[] = { env_string, NULL };
 
 	/* check for mandatory ops */
 	if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
@@ -197,6 +199,8 @@ int mdev_register_device(struct device *dev, const struct mdev_parent_ops *ops)
 	mutex_unlock(&parent_list_lock);
 
 	dev_info(dev, "MDEV: Registered\n");
+	kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
+
 	return 0;
 
 add_dev_err:
@@ -220,6 +224,8 @@ EXPORT_SYMBOL(mdev_register_device);
 void mdev_unregister_device(struct device *dev)
 {
 	struct mdev_parent *parent;
+	char *env_string = "MDEV_STATE=unregistered";
+	char *envp[] = { env_string, NULL };
 
 	mutex_lock(&parent_list_lock);
 	parent = __find_parent_device(dev);
@@ -243,6 +249,9 @@ void mdev_unregister_device(struct device *dev)
 	up_write(&parent->unreg_sem);
 
 	mdev_put_parent(parent);
+
+	/* We still have the caller's reference to use for the uevent */
+	kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
 }
 EXPORT_SYMBOL(mdev_unregister_device);
 

Re: [PATCH v3] mdev: Send uevents around parent device registration

[Kirti Wankhede]

On 7/10/2019 11:11 PM, Alex Williamson wrote:
> This allows udev to trigger rules when a parent device is registered
> or unregistered from mdev.
> 
> Reviewed-by: Cornelia Huck <cohuck@redhat.com>
> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
> ---
> 
> v3: Add Connie's R-b
>     Add comment clarifying expected device requirements for unreg
> 

Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>

Thanks,
Kirti

>  drivers/vfio/mdev/mdev_core.c |    9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
> index ae23151442cb..23976db6c6c7 100644
> --- a/drivers/vfio/mdev/mdev_core.c
> +++ b/drivers/vfio/mdev/mdev_core.c
> @@ -146,6 +146,8 @@ int mdev_register_device(struct device *dev, const struct mdev_parent_ops *ops)
>  {
>  	int ret;
>  	struct mdev_parent *parent;
> +	char *env_string = "MDEV_STATE=registered";
> +	char *envp[] = { env_string, NULL };
>  
>  	/* check for mandatory ops */
>  	if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
> @@ -197,6 +199,8 @@ int mdev_register_device(struct device *dev, const struct mdev_parent_ops *ops)
>  	mutex_unlock(&parent_list_lock);
>  
>  	dev_info(dev, "MDEV: Registered\n");
> +	kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
> +
>  	return 0;
>  
>  add_dev_err:
> @@ -220,6 +224,8 @@ EXPORT_SYMBOL(mdev_register_device);
>  void mdev_unregister_device(struct device *dev)
>  {
>  	struct mdev_parent *parent;
> +	char *env_string = "MDEV_STATE=unregistered";
> +	char *envp[] = { env_string, NULL };
>  
>  	mutex_lock(&parent_list_lock);
>  	parent = __find_parent_device(dev);
> @@ -243,6 +249,9 @@ void mdev_unregister_device(struct device *dev)
>  	up_write(&parent->unreg_sem);
>  
>  	mdev_put_parent(parent);
> +
> +	/* We still have the caller's reference to use for the uevent */
> +	kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
>  }
>  EXPORT_SYMBOL(mdev_unregister_device);
>  
>