From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:33358 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728044AbeJFB3u (ORCPT ); Fri, 5 Oct 2018 21:29:50 -0400 Date: Fri, 5 Oct 2018 14:29:49 -0400 From: Mike Snitzer To: Damien Le Moal Cc: dm-devel@redhat.com, linux-block@vger.kernel.org Subject: Re: dm: Fix report zone remapping Message-ID: <20181005182948.GA5628@redhat.com> References: <20181005103452.7134-1-damien.lemoal@wdc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20181005103452.7134-1-damien.lemoal@wdc.com> Sender: linux-block-owner@vger.kernel.org List-Id: linux-block@vger.kernel.org On Fri, Oct 05 2018 at 6:34am -0400, Damien Le Moal wrote: > If dm-linear or dm-flakey have targets on top of a partition of a zoned > block device, remapping of the start sector and write pointer position > of the zones reported by a report zones BIO must be modified to not > only account for the target table entry mapping, but also to account > for the partition first sector. This start sector must be substracted > to the start sector of all zones reported. The write pointer position > of sequential zones must also be reduced by this offset. > > Since there is no easy way to access the underlying bdev of the target > table entry from the dm_target or dm_target_io pointers, modify the > interface of the function dm_remap_zone_report() to allow a target to > pass the partition block device starting sector (offset). > > Fixes: 10999307c14e ("dm: introduce dm_remap_zone_report()") > Signed-off-by: Damien Le Moal > Cc: [dropping the actual stable cc from the mail, please don't cc stable in the mail header, could be that git-send-email just pulled it in but...] This needs a different fix. There should be absolutely no need to pass in a start offset for a device that is already supposed to be described within the 'struct bio' passed to dm_remap_zone_report(). Why can't you just use the bio->bi_bdev ? Err, since commit 74d46992e0d9d, I mean bio->bi_disk to get the start sector? You should be able to get it from: struct hd_struct *part = disk_get_part(bio->bi_disk, bio->bi_partno); part->start_sect; disk_put_part(part); or: struct block_device *bdev = bdget_disk(bio->bi_disk, bio->bi_partno); get_start_sect(fc->dev->bdev); bdput(bdev); Mike > --- > drivers/md/dm-flakey.c | 3 ++- > drivers/md/dm-linear.c | 3 ++- > drivers/md/dm.c | 16 ++++++++++++---- > include/linux/device-mapper.h | 2 +- > 4 files changed, 17 insertions(+), 7 deletions(-) > > diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c > index 21d126a5078c..c68c2e9cde6b 100644 > --- a/drivers/md/dm-flakey.c > +++ b/drivers/md/dm-flakey.c > @@ -381,7 +381,8 @@ static int flakey_end_io(struct dm_target *ti, struct bio *bio, > return DM_ENDIO_DONE; > > if (bio_op(bio) == REQ_OP_ZONE_REPORT) { > - dm_remap_zone_report(ti, bio, fc->start); > + dm_remap_zone_report(ti, bio, get_start_sect(fc->dev->bdev), > + fc->start); > return DM_ENDIO_DONE; > } > > diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c > index d10964d41fd7..f8cd367abbf6 100644 > --- a/drivers/md/dm-linear.c > +++ b/drivers/md/dm-linear.c > @@ -108,7 +108,8 @@ static int linear_end_io(struct dm_target *ti, struct bio *bio, > struct linear_c *lc = ti->private; > > if (!*error && bio_op(bio) == REQ_OP_ZONE_REPORT) > - dm_remap_zone_report(ti, bio, lc->start); > + dm_remap_zone_report(ti, bio, get_start_sect(lc->dev->bdev), > + lc->start); > > return DM_ENDIO_DONE; > } > diff --git a/drivers/md/dm.c b/drivers/md/dm.c > index 20f7e4ef5342..ffd8544eedd8 100644 > --- a/drivers/md/dm.c > +++ b/drivers/md/dm.c > @@ -1162,7 +1162,8 @@ EXPORT_SYMBOL_GPL(dm_accept_partial_bio); > * REQ_OP_ZONE_REPORT bio to remap the zone descriptors obtained > * from the target device mapping to the dm device. > */ > -void dm_remap_zone_report(struct dm_target *ti, struct bio *bio, sector_t start) > +void dm_remap_zone_report(struct dm_target *ti, struct bio *bio, > + sector_t dev_offset, sector_t start) > { > #ifdef CONFIG_BLK_DEV_ZONED > struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); > @@ -1195,18 +1196,25 @@ void dm_remap_zone_report(struct dm_target *ti, struct bio *bio, sector_t start) > /* Set zones start sector */ > while (hdr->nr_zones && ofst < bvec.bv_len) { > zone = addr + ofst; > + zone->start -= dev_offset; > if (zone->start >= start + ti->len) { > hdr->nr_zones = 0; > break; > } > zone->start = zone->start + ti->begin - start; > if (zone->type != BLK_ZONE_TYPE_CONVENTIONAL) { > - if (zone->cond == BLK_ZONE_COND_FULL) > + switch (zone->cond) { > + case BLK_ZONE_COND_FULL: > zone->wp = zone->start + zone->len; > - else if (zone->cond == BLK_ZONE_COND_EMPTY) > + break; > + case BLK_ZONE_COND_EMPTY: > zone->wp = zone->start; > - else > + break; > + default: > + zone->wp -= dev_offset; > zone->wp = zone->wp + ti->begin - start; > + break; > + } > } > ofst += sizeof(struct blk_zone); > hdr->nr_zones--; > diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h > index 6fb0808e87c8..22c1924c0ee8 100644 > --- a/include/linux/device-mapper.h > +++ b/include/linux/device-mapper.h > @@ -421,7 +421,7 @@ int dm_suspended(struct dm_target *ti); > int dm_noflush_suspending(struct dm_target *ti); > void dm_accept_partial_bio(struct bio *bio, unsigned n_sectors); > void dm_remap_zone_report(struct dm_target *ti, struct bio *bio, > - sector_t start); > + sector_t dev_offset, sector_t start); > union map_info *dm_get_rq_mapinfo(struct request *rq); > > struct queue_limits *dm_get_queue_limits(struct mapped_device *md); > -- > 2.17.1 >