block: inherit the zoned characteristics in blk_stack_limits

Lift the code from device mapper into blk_stack_limits to inherity
the stacking limitations.  This ensures we do the right thing for
all stacked zoned block devices.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Tested-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-settings.c b/block/blk-settings.c
index 9a2c23c..9cddbd7 100644 (file)
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -609,6 +609,7 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
                t->chunk_sectors = min_not_zero(t->chunk_sectors,
                                                b->chunk_sectors);
 
+       t->zoned = max(t->zoned, b->zoned);
        return ret;
 }
 EXPORT_SYMBOL(blk_stack_limits);

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 0ea5b73..ec53641 100644 (file)
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -467,9 +467,6 @@ static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
                       q->limits.logical_block_size,
                       q->limits.alignment_offset,
                       (unsigned long long) start << SECTOR_SHIFT);
-
-       limits->zoned = blk_queue_zoned_model(q);
-
        return 0;
 }
 
@@ -1528,22 +1525,6 @@ combine_limits:
                               dm_device_name(table->md),
                               (unsigned long long) ti->begin,
                               (unsigned long long) ti->len);
-
-               /*
-                * FIXME: this should likely be moved to blk_stack_limits(), would
-                * also eliminate limits->zoned stacking hack in dm_set_device_limits()
-                */
-               if (limits->zoned == BLK_ZONED_NONE && ti_limits.zoned != BLK_ZONED_NONE) {
-                       /*
-                        * By default, the stacked limits zoned model is set to
-                        * BLK_ZONED_NONE in blk_set_stacking_limits(). Update
-                        * this model using the first target model reported
-                        * that is not BLK_ZONED_NONE. This will be either the
-                        * first target device zoned model or the model reported
-                        * by the target .io_hints.
-                        */
-                       limits->zoned = ti_limits.zoned;
-               }
        }
 
        /*

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 6307894..9e331a1 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -306,11 +306,14 @@ enum blk_queue_state {
 
 /*
  * Zoned block device models (zoned limit).
+ *
+ * Note: This needs to be ordered from the least to the most severe
+ * restrictions for the inheritance in blk_stack_limits() to work.
  */
 enum blk_zoned_model {
-       BLK_ZONED_NONE, /* Regular block device */
-       BLK_ZONED_HA,   /* Host-aware zoned block device */
-       BLK_ZONED_HM,   /* Host-managed zoned block device */
+       BLK_ZONED_NONE = 0,     /* Regular block device */
+       BLK_ZONED_HA,           /* Host-aware zoned block device */
+       BLK_ZONED_HM,           /* Host-managed zoned block device */
 };
 
 struct queue_limits {