Re: [RFC 5/8] kmsg: device support in mem class

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Fri, Jul 03, 2015 at 12:49:52PM +0200, Marcin Niesluchowski wrote:
> Mem class is current class in which kmsg device is holded in.
> 
> Mem class is exteded by kmsg_sys devices handling.
> 
> Signed-off-by: Marcin Niesluchowski <m.niesluchow@samsung.com>
> ---
>  drivers/char/mem.c | 20 ++++++++++++++++++--
>  1 file changed, 18 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/char/mem.c b/drivers/char/mem.c
> index e518040..8d5ba0d 100644
> --- a/drivers/char/mem.c
> +++ b/drivers/char/mem.c
> @@ -815,7 +815,11 @@ static int memory_open(struct inode *inode, struct file *filp)
>  
>  	minor = iminor(inode);
>  	if (minor >= ARRAY_SIZE(devlist))
> +#ifdef CONFIG_PRINTK
> +		minor = KMSG_MINOR;
> +#else
>  		return -ENXIO;
> +#endif

Ick, you are going to have to come up with a better api if you want this
to be able to be merged.  I don't want to see #ifdef in .c files, as
these changes just make things much messier.

> @@ -837,8 +841,20 @@ static const struct file_operations memory_fops = {
>  
>  static char *mem_devnode(struct device *dev, umode_t *mode)
>  {
> -	if (mode && devlist[MINOR(dev->devt)].mode)
> -		*mode = devlist[MINOR(dev->devt)].mode;
> +	int minor;
> +
> +	if (!mode)
> +		return NULL;
> +
> +	minor = MINOR(dev->devt);
> +
> +#ifdef CONFIG_PRINTK
> +	if (minor >= ARRAY_SIZE(devlist))
> +		kmsg_sys_mode(minor, mode);
> +	else
> +#endif

Ick, not ok.

greg k-h