From: Christoph Hellwig hch@lst.de
commit 89f871af1b26d98d983cba7ed0e86effa45ba5f8 upstream.
device mapper is currently the only outlier that tries to call register_disk after add_disk, leading to fairly inconsistent state of these block layer data structures. Instead change device-mapper to just register the gendisk later now that the holder mechanism can cope with that.
Note that this introduces a user visible change: the dm kobject is now only visible after the initial table has been loaded.
Signed-off-by: Christoph Hellwig hch@lst.de Reviewed-by: Mike Snitzer snitzer@redhat.com Signed-off-by: Yu Kuai yukuai3@huawei.com --- drivers/md/dm.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-)
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index ab0e2338e47e..85efe2f1995f 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1795,7 +1795,12 @@ static void cleanup_mapped_device(struct mapped_device *md) spin_lock(&_minor_lock); md->disk->private_data = NULL; spin_unlock(&_minor_lock); - del_gendisk(md->disk); + if (dm_get_md_type(md) != DM_TYPE_NONE) { + dm_sysfs_exit(md); + del_gendisk(md->disk); + } else { + md->disk->queue = NULL; + } put_disk(md->disk); }
@@ -1900,7 +1905,6 @@ static struct mapped_device *alloc_dev(int minor) } }
- add_disk_no_queue_reg(md->disk); format_dev_t(md->name, MKDEV(_major, minor));
md->wq = alloc_workqueue("kdmflush", WQ_MEM_RECLAIM, 0); @@ -2098,19 +2102,12 @@ static struct dm_table *__unbind(struct mapped_device *md) */ int dm_create(int minor, struct mapped_device **result) { - int r; struct mapped_device *md;
md = alloc_dev(minor); if (!md) return -ENXIO;
- r = dm_sysfs_init(md); - if (r) { - free_dev(md); - return r; - } - *result = md; return 0; } @@ -2188,8 +2185,14 @@ int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t) return r; } dm_table_set_restrictions(t, md->queue, &limits); - blk_register_queue(md->disk);
+ add_disk(md->disk); + r = dm_sysfs_init(md); + if (r) { + del_gendisk(md->disk); + return r; + } + md->type = type; return 0; }
@@ -2295,7 +2298,6 @@ static void __dm_destroy(struct mapped_device *md, bool wait) DMWARN("%s: Forcibly removing mapped_device still in use! (%d users)", dm_device_name(md), atomic_read(&md->holders));
- dm_sysfs_exit(md); dm_table_destroy(__unbind(md)); free_dev(md); }