On 1/21/20 2:06 PM, Dan Carpenter wrote:
> The IDE core always sets ->dn correctly so changing it is never
> required.
>
> Setting it to a different value than assigned by IDE core is very likely
> to result in data corruption (due to wrong transfer timings being set on
> the controller etc.)
>
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Thanks, it looks fine (though patch summary can be improved further i.e.:
"[PATCH] ide-proc: make "number" setting read-only").
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
I've also verified it (using ARAnyM emulator):
Tested-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics
> ---
>
> include/linux/ide.h | 4 ++++
> drivers/ide/ide-proc.c | 2 +-
> 2 files changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/include/linux/ide.h b/include/linux/ide.h
> index 06dae6438557..a254841bd315 100644
> --- a/include/linux/ide.h
> +++ b/include/linux/ide.h
> @@ -945,6 +945,10 @@ ide_devset_get(_name, _field); \
> ide_devset_set(_name, _field); \
> IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name)
>
> +#define ide_devset_ro_field(_name, _field) \
> +ide_devset_get(_name, _field); \
> +IDE_DEVSET(_name, 0, get_##_name, NULL)
> +
> #define ide_devset_rw_flag(_name, _field) \
> ide_devset_get_flag(_name, _field); \
> ide_devset_set_flag(_name, _field); \
> diff --git a/drivers/ide/ide-proc.c b/drivers/ide/ide-proc.c
> index 11a801aa92d8..15c17f3781ee 100644
> --- a/drivers/ide/ide-proc.c
> +++ b/drivers/ide/ide-proc.c
> @@ -206,7 +206,7 @@ static int set_xfer_rate (ide_drive_t *drive, int arg)
> ide_devset_rw(current_speed, xfer_rate);
> ide_devset_rw_field(init_speed, init_speed);
> ide_devset_rw_flag(nice1, IDE_DFLAG_NICE1);
> -ide_devset_rw_field(number, dn);
> +ide_devset_ro_field(number, dn);
>
> static const struct ide_proc_devset ide_generic_settings[] = {
> IDE_PROC_DEVSET(current_speed, 0, 70),
>
