Re: [PATCH 05/31] cdrom: track if a cdrom_device_info was opened for data

[Hannes Reinecke <hare@xxxxxxx>]

On 6/6/23 09:39, Christoph Hellwig wrote:
> Set a flag when a cdrom_device_info is opened for writing, instead of
> trying to figure out this at release time.  This will allow to eventually
> remove the mode argument to the ->release block_device_operation as
> nothing but the CDROM drivers uses that argument.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
>   drivers/cdrom/cdrom.c | 12 +++++-------
>   include/linux/cdrom.h |  1 +
>   2 files changed, 6 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c
> index 08abf1ffede002..adebac1bd210d9 100644
> --- a/drivers/cdrom/cdrom.c
> +++ b/drivers/cdrom/cdrom.c
> @@ -1172,6 +1172,7 @@ int cdrom_open(struct cdrom_device_info *cdi, fmode_t mode)
>   			ret = 0;
>   			cdi->media_written = 0;
>   		}
> +		cdi->opened_for_data = true;
>   	}
>   
>   	if (ret)
> @@ -1252,7 +1253,6 @@ static int check_for_audio_disc(struct cdrom_device_info *cdi,
>   void cdrom_release(struct cdrom_device_info *cdi, fmode_t mode)
>   {
>   	const struct cdrom_device_ops *cdo = cdi->ops;
> -	int opened_for_data;
>   
>   	cd_dbg(CD_CLOSE, "entering cdrom_release\n");
>   
> @@ -1270,14 +1270,12 @@ void cdrom_release(struct cdrom_device_info *cdi, fmode_t mode)
>   		}
>   	}
>   
> -	opened_for_data = !(cdi->options & CDO_USE_FFLAGS) ||
> -		!(mode & FMODE_NDELAY);
> -
>   	cdo->release(cdi);
> -	if (cdi->use_count == 0) {      /* last process that closes dev*/
> -		if (opened_for_data &&
> -		    cdi->options & CDO_AUTO_EJECT && CDROM_CAN(CDC_OPEN_TRAY))
> +
> +	if (cdi->use_count == 0 && cdi->opened_for_data) {
> +		if (cdi->options & CDO_AUTO_EJECT && CDROM_CAN(CDC_OPEN_TRAY))
>   			cdo->tray_move(cdi, 1);
> +		cdi->opened_for_data = false;
>   	}
>   }
>   EXPORT_SYMBOL(cdrom_release);
> diff --git a/include/linux/cdrom.h b/include/linux/cdrom.h
> index 0a5db0b0c958a1..385e94732b2cf1 100644
> --- a/include/linux/cdrom.h
> +++ b/include/linux/cdrom.h
> @@ -64,6 +64,7 @@ struct cdrom_device_info {
>   	int (*exit)(struct cdrom_device_info *);
>   	int mrw_mode_page;
>   	__s64 last_media_change_ms;
> +	bool opened_for_data;
>   };
>   
>   struct cdrom_device_ops {

Do we care about alignment here?
integer followed by a 64 bit value followed by a bool seems
like an automatic padding to me ...

Cheers,

Hannes