On Tue, Nov 12, 2024 at 4:43 AM John Garry <john.g.garry@xxxxxxxxxx> wrote:
>
> Set BLK_FEAT_ATOMIC_WRITES_STACKED to enable atomic writes.
>
> For an attempt to atomic write to a region which has bad blocks, error
> the write as we just cannot do this. It is unlikely to find devices which
> support atomic writes and bad blocks.
>
> Signed-off-by: John Garry <john.g.garry@xxxxxxxxxx>
> ---
> drivers/md/raid10.c | 14 ++++++++++++--
> 1 file changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
> index 8c7f5daa073a..a3936a67e1e8 100644
> --- a/drivers/md/raid10.c
> +++ b/drivers/md/raid10.c
> @@ -1255,6 +1255,7 @@ static void raid10_write_one_disk(struct mddev *mddev, struct r10bio *r10_bio,
> const enum req_op op = bio_op(bio);
> const blk_opf_t do_sync = bio->bi_opf & REQ_SYNC;
> const blk_opf_t do_fua = bio->bi_opf & REQ_FUA;
> + const blk_opf_t do_atomic = bio->bi_opf & REQ_ATOMIC;
> unsigned long flags;
> struct r10conf *conf = mddev->private;
> struct md_rdev *rdev;
> @@ -1273,7 +1274,7 @@ static void raid10_write_one_disk(struct mddev *mddev, struct r10bio *r10_bio,
> mbio->bi_iter.bi_sector = (r10_bio->devs[n_copy].addr +
> choose_data_offset(r10_bio, rdev));
> mbio->bi_end_io = raid10_end_write_request;
> - mbio->bi_opf = op | do_sync | do_fua;
> + mbio->bi_opf = op | do_sync | do_fua | do_atomic;
> if (!replacement && test_bit(FailFast,
> &conf->mirrors[devnum].rdev->flags)
> && enough(conf, devnum))
> @@ -1468,7 +1469,15 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio,
> continue;
> }
> if (is_bad) {
> - int good_sectors = first_bad - dev_sector;
> + int good_sectors;
> +
> + if (bio->bi_opf & REQ_ATOMIC) {
> + /* We just cannot atomically write this ... */
> + error = -EFAULT;
Is EFAULT the right error code here? I think we should return something
covered by blk_errors?
Other than this, 4/5 and 5/5 look good to me.
Thanks,
Song
