Re: [PATCH 2/2] ubi: Expose the bitrot interface

[Boris Brezillon <boris.brezillon@bootlin.com>]

On Wed,  7 Nov 2018 23:16:19 +0100
Richard Weinberger <richard@nod.at> wrote:

> +/**
> + * ubi_bitflip_check - Check an eraseblock for bitflips and scrub it if needed.
> + * @ubi: UBI device description object
> + * @pnum: the physical eraseblock to schedule
> + * @force_scrub: force scrubbing if non-zero, schedule erase otherwise

Are you sure about the "schedule erase otherwise"? I'd say force_scrub
only influence when the scrub operation is done: either unconditionally
or depending on the result of ubi_io_read().

> + *
> + * This function reads the given eraseblock and checks if bitflips occured.
> + * In case of bitflips, the eraseblock is scheduled for scrubbing.
> + * If scrubbing is forced with @force_scrub, the eraseblock is not read,
> + * but scheduled for scrubbing right away.
> + *
> + * Returns:
> + * %EINVAL, PEB is out of range
> + * %ENOENT, PEB is no longer used by UBI
> + * %EBUSY, PEB cannot be checked now or a check is currently running on it
> + * %EAGAIN, bit flips happened but scrubbing is currently not possible
> + * %EUCLEAN, bit flips happened and PEB is scheduled for scrubbing
> + * %0, no bit flips detected
> + */
> +int ubi_bitflip_check(struct ubi_device *ubi, int pnum, int force_scrub)