Re: [dm-devel] [PATCH v7 12/13] dm: call dm_zone_endio after the target endio callback for zoned devices

From: Pankaj Raghav
Date: Thu Jun 16 2022 - 09:01:30 EST


On 2022-06-15 13:01, Damien Le Moal wrote:
> On 6/15/22 19:19, Pankaj Raghav wrote:
>> dm_zone_endio() updates the bi_sector of orig bio for zoned devices that
>> uses either native append or append emulation and it is called before the
>> endio of the target. But target endio can still update the clone bio
>> after dm_zone_endio is called, thereby, the orig bio does not contain
>> the updated information anymore. Call dm_zone_endio for zoned devices
>> after calling the target's endio function
>>
>> Signed-off-by: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
>> ---
>> @Damien and @Hannes: I couldn't come up with a testcase that uses endio callback and
>> zone append or append emulation for zoned devices to test for
>> regression in this change. It would be great if you can suggest
>> something. This change is required for the npo2 target as we update the
>> clone bio sector in the endio callback function and the orig bio should
>> be updated only after the endio callback for zone appends.
>
> Running zonefs tests on top of dm-crypt will exercise DM zone append
> emulation.
>
Thanks. However, I am facing issues creating a dm-crypt target with a
zoned device. Steps:
- cryptsetup luksFormat <zns-device>

is throwing a bunch of IO errors with the following error message:
Device wipe error, offset 32768.
Cannot wipe header on device <zns-device>.

I can observe the same behavior in both v5.18 and next-20220615 with
cryptsetup 2.4.3.The same step is working correctly on a normal NVMe device.
Am I doing something wrong?
ZNS info: zsze 128M and zcap 128M with 50 zones
>>
>> drivers/md/dm.c | 8 ++++----
>> 1 file changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/md/dm.c b/drivers/md/dm.c
>> index 3f17fe1de..3a74e1038 100644
>> --- a/drivers/md/dm.c
>> +++ b/drivers/md/dm.c
>> @@ -1025,10 +1025,6 @@ static void clone_endio(struct bio *bio)
>> disable_write_zeroes(md);
>> }
>>
>> - if (static_branch_unlikely(&zoned_enabled) &&
>> - unlikely(blk_queue_is_zoned(bdev_get_queue(bio->bi_bdev))))
>> - dm_zone_endio(io, bio);
>> -
>> if (endio) {
>> int r = endio(ti, bio, &error);
>> switch (r) {
>> @@ -1057,6 +1053,10 @@ static void clone_endio(struct bio *bio)
>> }
>> }
>>
>> + if (static_branch_unlikely(&zoned_enabled) &&
>> + unlikely(blk_queue_is_zoned(bdev_get_queue(bio->bi_bdev))))
>
> blk_queue_is_zoned(bdev_get_queue(bio->bi_bdev))) ->
> bdev_is_zoned(bio->bi_bdev)
>
Ok. Even though I just moved the statements, I think this is trivial
enough to take it along.
>> + dm_zone_endio(io, bio);
>> +
>> if (static_branch_unlikely(&swap_bios_enabled) &&
>> unlikely(swap_bios_limit(ti, bio)))
>> up(&md->swap_bios_semaphore);
>
>