Re: [Intel-xe] [PATCH 1/2] devcoredump: Add dev_coredump_put()

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Thu, Nov 23, 2023 at 10:06:04AM -0800, José Roberto de Souza wrote:
> Add function to remove device coredump, this is useful to release
> resources allocated by device before unload.
> Without this coredump would only be removed after DEVCD_TIMEOUT
> seconds.
> 
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>

yeap, I also bumped into this a while back, but I was holding the
patch so we send to the right community when we are in tree:

https://gitlab.freedesktop.org/rodrigovivi/drm-xe/-/commit/fd35f04e4317a35c5a92509f30f5399caea7748f

https://gitlab.freedesktop.org/rodrigovivi/drm-xe/-/commits/devcoredump-removal/?ref_type=heads

> Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
> ---
>  drivers/base/devcoredump.c  | 21 +++++++++++++++++++++
>  include/linux/devcoredump.h |  5 +++++
>  2 files changed, 26 insertions(+)
> 
> diff --git a/drivers/base/devcoredump.c b/drivers/base/devcoredump.c
> index 91536ee05f144..444bb510b6ef4 100644
> --- a/drivers/base/devcoredump.c
> +++ b/drivers/base/devcoredump.c
> @@ -304,6 +304,27 @@ static ssize_t devcd_read_from_sgtable(char *buffer, loff_t offset,
>  				  offset);
>  }
>  
> +/**
> + * dev_coredump_put - remove device coredump
> + * @dev: the struct device for the crashed device
> + *
> + * If giving device has a coredump this frees data and remove coredump,
> + * otherwise does nothing.
> + * This is useful to release resources allocated by device before unload it.
> + */
> +void dev_coredump_put(struct device *dev)
> +{
> +	struct device *existing;
> +
> +	existing = class_find_device(&devcd_class, NULL, dev,
> +				     devcd_match_failing);
> +	if (existing) {
> +		devcd_free(existing, NULL);
> +		put_device(existing);
> +	}
> +}
> +EXPORT_SYMBOL_GPL(dev_coredump_put);
> +
>  /**
>   * dev_coredumpm - create device coredump with read/free methods
>   * @dev: the struct device for the crashed device
> diff --git a/include/linux/devcoredump.h b/include/linux/devcoredump.h
> index c008169ed2c6f..c8f7eb6cc1915 100644
> --- a/include/linux/devcoredump.h
> +++ b/include/linux/devcoredump.h
> @@ -63,6 +63,8 @@ void dev_coredumpm(struct device *dev, struct module *owner,
>  
>  void dev_coredumpsg(struct device *dev, struct scatterlist *table,
>  		    size_t datalen, gfp_t gfp);
> +
> +void dev_coredump_put(struct device *dev);
>  #else
>  static inline void dev_coredumpv(struct device *dev, void *data,
>  				 size_t datalen, gfp_t gfp)
> @@ -85,6 +87,9 @@ static inline void dev_coredumpsg(struct device *dev, struct scatterlist *table,
>  {
>  	_devcd_free_sgtable(table);
>  }
> +static inline void dev_coredump_put(struct device *dev)
> +{
> +}
>  #endif /* CONFIG_DEV_COREDUMP */
>  
>  #endif /* __DEVCOREDUMP_H */
> -- 
> 2.42.1
>