Re: [PATCH 1/7] debugfs: Add debugfs_create_xul() for hexadecimal unsigned long

[Greg Kroah-Hartman]

On Mon, Oct 21, 2019 at 04:37:36PM +0200, Geert Uytterhoeven wrote:
> The existing debugfs_create_ulong() function supports objects of
> type "unsigned long", which are 32-bit or 64-bit depending on the
> platform, in decimal form.  To format objects in hexadecimal, various
> debugfs_create_x*() functions exist, but all of them take fixed-size
> types.
> 
> Add a debugfs helper for "unsigned long" objects in hexadecimal format.
> This avoids the need for users to open-code the same, or introduce
> bugs when casting the value pointer to "u32 *" or "u64 *" to call
> debugfs_create_x{32,64}().
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> ---
>  include/linux/debugfs.h | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h
> index 33690949b45d6904..d7b2aebcc277d65e 100644
> --- a/include/linux/debugfs.h
> +++ b/include/linux/debugfs.h
> @@ -356,4 +356,14 @@ static inline ssize_t debugfs_write_file_bool(struct file *file,
>  
>  #endif
>  
> +static inline void debugfs_create_xul(const char *name, umode_t mode,
> +				      struct dentry *parent,
> +				      unsigned long *value)
> +{
> +	if (sizeof(*value) == sizeof(u32))
> +		debugfs_create_x32(name, mode, parent, (u32 *)value);
> +	else
> +		debugfs_create_x64(name, mode, parent, (u64 *)value);
> +}

Looks sane, but can you add some kernel-doc comments here so that we can
pull it into the debugfs documentation?  Also there is debugfs
documentation in Documentation/filesystems/ so maybe also add this
there?  I am going to be overhauling the debugfs documentation "soon"
but it's at the lower part of my todo list, so it will take a while,
might as well keep it up to date with new stuff added like this so that
people don't get lost.

thanks,

greg k-h