From: Mike Snitzer snitzer@redhat.com
[ Upstream commit 6ba01df72b4b63a26b4977790f58d8f775d2992c ]
Partitioned request-based devices cannot be used as underlying devices for request-based DM because no partition offsets are added to each incoming request. As such, until now, stacking on partitioned devices would _always_ result in data corruption (e.g. wiping the partition table, writing to other partitions, etc). Fix this by disallowing request-based stacking on partitions.
While at it, since all .request_fn support has been removed from block core, remove legacy dm-table code that differentiated between blk-mq and .request_fn request-based.
Signed-off-by: Mike Snitzer snitzer@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/dm-table.c | 27 ++++++++------------------- 1 file changed, 8 insertions(+), 19 deletions(-)
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 52e049554f5cd..2ae0c19137667 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -918,21 +918,15 @@ bool dm_table_supports_dax(struct dm_table *t,
static bool dm_table_does_not_support_partial_completion(struct dm_table *t);
-struct verify_rq_based_data { - unsigned sq_count; - unsigned mq_count; -}; - -static int device_is_rq_based(struct dm_target *ti, struct dm_dev *dev, - sector_t start, sector_t len, void *data) +static int device_is_rq_stackable(struct dm_target *ti, struct dm_dev *dev, + sector_t start, sector_t len, void *data) { - struct request_queue *q = bdev_get_queue(dev->bdev); - struct verify_rq_based_data *v = data; + struct block_device *bdev = dev->bdev; + struct request_queue *q = bdev_get_queue(bdev);
- if (queue_is_mq(q)) - v->mq_count++; - else - v->sq_count++; + /* request-based cannot stack on partitions! */ + if (bdev != bdev->bd_contains) + return false;
return queue_is_mq(q); } @@ -941,7 +935,6 @@ static int dm_table_determine_type(struct dm_table *t) { unsigned i; unsigned bio_based = 0, request_based = 0, hybrid = 0; - struct verify_rq_based_data v = {.sq_count = 0, .mq_count = 0}; struct dm_target *tgt; struct list_head *devices = dm_table_get_devices(t); enum dm_queue_mode live_md_type = dm_get_md_type(t->md); @@ -1045,14 +1038,10 @@ verify_rq_based:
/* Non-request-stackable devices can't be used for request-based dm */ if (!tgt->type->iterate_devices || - !tgt->type->iterate_devices(tgt, device_is_rq_based, &v)) { + !tgt->type->iterate_devices(tgt, device_is_rq_stackable, NULL)) { DMERR("table load rejected: including non-request-stackable devices"); return -EINVAL; } - if (v.sq_count > 0) { - DMERR("table load rejected: not all devices are blk-mq request-stackable"); - return -EINVAL; - }
return 0; }