| Message ID | 20201116145809.410558-66-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/78] block: remove the call to __invalidate_device in check_disk_size_change | expand |
On 11/16/20 3:57 PM, Christoph Hellwig wrote: > Get rid of the long-lasting struct block_device reference in > struct mapped_device. The only remaining user is the freeze code, > where we can trivially look up the block device at freeze time > and release the reference at thaw time. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > drivers/md/dm-core.h | 2 -- > drivers/md/dm.c | 22 +++++++++++----------- > 2 files changed, 11 insertions(+), 13 deletions(-) > > diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h > index d522093cb39dda..b1b400ed76fe90 100644 > --- a/drivers/md/dm-core.h > +++ b/drivers/md/dm-core.h > @@ -107,8 +107,6 @@ struct mapped_device { > /* kobject and completion */ > struct dm_kobject_holder kobj_holder; > > - struct block_device *bdev; > - > struct dm_stats stats; > > /* for blk-mq request-based DM support */ > diff --git a/drivers/md/dm.c b/drivers/md/dm.c > index 6d7eb72d41f9ea..c789ffea2badde 100644 > --- a/drivers/md/dm.c > +++ b/drivers/md/dm.c > @@ -1744,11 +1744,6 @@ static void cleanup_mapped_device(struct mapped_device *md) > > cleanup_srcu_struct(&md->io_barrier); > > - if (md->bdev) { > - bdput(md->bdev); > - md->bdev = NULL; > - } > - > mutex_destroy(&md->suspend_lock); > mutex_destroy(&md->type_lock); > mutex_destroy(&md->table_devices_lock); > @@ -1840,10 +1835,6 @@ static struct mapped_device *alloc_dev(int minor) > if (!md->wq) > goto bad; > > - md->bdev = bdget_disk(md->disk, 0); > - if (!md->bdev) > - goto bad; > - > dm_stats_init(&md->stats); > > /* Populate the mapping, nobody knows we exist yet */ > @@ -2384,12 +2375,17 @@ struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table) > */ > static int lock_fs(struct mapped_device *md) > { > + struct block_device *bdev; > int r; > > WARN_ON(md->frozen_sb); > > - md->frozen_sb = freeze_bdev(md->bdev); > + bdev = bdget_disk(md->disk, 0); > + if (!bdev) > + return -ENOMEM; > + md->frozen_sb = freeze_bdev(bdev); > if (IS_ERR(md->frozen_sb)) { > + bdput(bdev); > r = PTR_ERR(md->frozen_sb); > md->frozen_sb = NULL; > return r; > @@ -2402,10 +2398,14 @@ static int lock_fs(struct mapped_device *md) > > static void unlock_fs(struct mapped_device *md) > { > + struct block_device *bdev; > + > if (!test_bit(DMF_FROZEN, &md->flags)) > return; > > - thaw_bdev(md->bdev, md->frozen_sb); > + bdev = md->frozen_sb->s_bdev; > + thaw_bdev(bdev, md->frozen_sb); > + bdput(bdev); > md->frozen_sb = NULL; > clear_bit(DMF_FROZEN, &md->flags); > } > Yay. Just what I need for the blk-interposer code, where the ->bdev pointer is really getting in the way. Reviewed-by: Hannes Reinecke <hare@suse.de> Cheers, Hannes
diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h index d522093cb39dda..b1b400ed76fe90 100644 --- a/drivers/md/dm-core.h +++ b/drivers/md/dm-core.h @@ -107,8 +107,6 @@ struct mapped_device { /* kobject and completion */ struct dm_kobject_holder kobj_holder; - struct block_device *bdev; - struct dm_stats stats; /* for blk-mq request-based DM support */ diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 6d7eb72d41f9ea..c789ffea2badde 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1744,11 +1744,6 @@ static void cleanup_mapped_device(struct mapped_device *md) cleanup_srcu_struct(&md->io_barrier); - if (md->bdev) { - bdput(md->bdev); - md->bdev = NULL; - } - mutex_destroy(&md->suspend_lock); mutex_destroy(&md->type_lock); mutex_destroy(&md->table_devices_lock); @@ -1840,10 +1835,6 @@ static struct mapped_device *alloc_dev(int minor) if (!md->wq) goto bad; - md->bdev = bdget_disk(md->disk, 0); - if (!md->bdev) - goto bad; - dm_stats_init(&md->stats); /* Populate the mapping, nobody knows we exist yet */ @@ -2384,12 +2375,17 @@ struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table) */ static int lock_fs(struct mapped_device *md) { + struct block_device *bdev; int r; WARN_ON(md->frozen_sb); - md->frozen_sb = freeze_bdev(md->bdev); + bdev = bdget_disk(md->disk, 0); + if (!bdev) + return -ENOMEM; + md->frozen_sb = freeze_bdev(bdev); if (IS_ERR(md->frozen_sb)) { + bdput(bdev); r = PTR_ERR(md->frozen_sb); md->frozen_sb = NULL; return r; @@ -2402,10 +2398,14 @@ static int lock_fs(struct mapped_device *md) static void unlock_fs(struct mapped_device *md) { + struct block_device *bdev; + if (!test_bit(DMF_FROZEN, &md->flags)) return; - thaw_bdev(md->bdev, md->frozen_sb); + bdev = md->frozen_sb->s_bdev; + thaw_bdev(bdev, md->frozen_sb); + bdput(bdev); md->frozen_sb = NULL; clear_bit(DMF_FROZEN, &md->flags); }
Get rid of the long-lasting struct block_device reference in struct mapped_device. The only remaining user is the freeze code, where we can trivially look up the block device at freeze time and release the reference at thaw time. Signed-off-by: Christoph Hellwig <hch@lst.de> --- drivers/md/dm-core.h | 2 -- drivers/md/dm.c | 22 +++++++++++----------- 2 files changed, 11 insertions(+), 13 deletions(-)