Re: [PATCH 1/2] block: handle the null_mapped flag correctly in blk_rq_map_user_iov

[Jens Axboe]

On 02/11/2015 06:07 AM, Christoph Hellwig wrote:
> The tape drivers (and the sg driver in a special case that doesn't matter
> here) use the null_mapped flag to tell blk_rq_map_user to not copy around
> any data into or out of the bounce buffers.  blk_rq_map_user_iov never
> got that treatment, which didn't matter until I refactored blk_rq_map_user
> to be implemented in terms of blk_rq_map_user_iov.

So this fixes a regression caused by:

commit ddad8dd0a162fde61646a627a3017c258601dc8a
Author: Christoph Hellwig <hch@xxxxxx>
Date:   Sun Jan 18 16:16:29 2015 +0100

    block: use blk_rq_map_user_iov to implement blk_rq_map_user

    Signed-off-by: Christoph Hellwig <hch@xxxxxx>
    Reviewed-by: Ming Lei <tom.leiming@xxxxxxxxx>
    Signed-off-by: Jens Axboe <axboe@xxxxxx>

which we should probably note in the commit. I'll add that.


--
Jens Axboe

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/