block: Remove partition support for zoned block devices

No known partitioning tool supports zoned block devices, especially the
host managed flavor with strong sequential write constraints.
Furthermore, there are also no known user nor use cases for partitioned
zoned block devices.

This patch removes partition device creation for zoned block devices,
which allows simplifying the processing of zone commands for zoned
block devices. A warning is added if a partition table is found on the
device.

For report zones operations no zone sector information remapping is
necessary anymore, simplifying the code. Of note is that remapping of
zone reports for DM targets is still necessary as done by
dm_remap_zone_report().

Similarly, remaping of a zone reset bio is not necessary anymore.
Testing for the applicability of the zone reset all request also becomes
simpler and only needs to check that the number of sectors of the
requested zone range is equal to the disk capacity.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 11 insertions, 51 deletions

diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index ea4e086ba00e..ae665e490858 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -93,32 +93,10 @@ unsigned int blkdev_nr_zones(struct block_device *bdev)
 	if (!blk_queue_is_zoned(q))
 		return 0;
 
-	return __blkdev_nr_zones(q, bdev->bd_part->nr_sects);
+	return __blkdev_nr_zones(q, get_capacity(bdev->bd_disk));
 }
 EXPORT_SYMBOL_GPL(blkdev_nr_zones);
 
-/*
- * Check that a zone report belongs to this partition, and if yes, fix its start
- * sector and write pointer and return true. Return false otherwise.
- */
-static bool blkdev_report_zone(struct block_device *bdev, struct blk_zone *rep)
-{
-	sector_t offset = get_start_sect(bdev);
-
-	if (rep->start < offset)
-		return false;
-
-	rep->start -= offset;
-	if (rep->start + rep->len > bdev->bd_part->nr_sects)
-		return false;
-
-	if (rep->type == BLK_ZONE_TYPE_CONVENTIONAL)
-		rep->wp = rep->start + rep->len;
-	else
-		rep->wp -= offset;
-	return true;
-}
-
 /**
  * blkdev_report_zones - Get zones information
  * @bdev:	Target block device
@@ -140,8 +118,7 @@ int blkdev_report_zones(struct block_device *bdev, sector_t sector,
 {
 	struct request_queue *q = bdev_get_queue(bdev);
 	struct gendisk *disk = bdev->bd_disk;
-	unsigned int i, nrz;
-	int ret;
+	sector_t capacity = get_capacity(disk);
 
 	if (!blk_queue_is_zoned(q))
 		return -EOPNOTSUPP;
@@ -154,27 +131,14 @@ int blkdev_report_zones(struct block_device *bdev, sector_t sector,
 	if (WARN_ON_ONCE(!disk->fops->report_zones))
 		return -EOPNOTSUPP;
 
-	if (!*nr_zones || sector >= bdev->bd_part->nr_sects) {
+	if (!*nr_zones || sector >= capacity) {
 		*nr_zones = 0;
 		return 0;
 	}
 
-	nrz = min(*nr_zones,
-		  __blkdev_nr_zones(q, bdev->bd_part->nr_sects - sector));
-	ret = disk->fops->report_zones(disk, get_start_sect(bdev) + sector,
-				       zones, &nrz);
-	if (ret)
-		return ret;
+	*nr_zones = min(*nr_zones, __blkdev_nr_zones(q, capacity - sector));
 
-	for (i = 0; i < nrz; i++) {
-		if (!blkdev_report_zone(bdev, zones))
-			break;
-		zones++;
-	}
-
-	*nr_zones = i;
-
-	return 0;
+	return disk->fops->report_zones(disk, sector, zones, nr_zones);
 }
 EXPORT_SYMBOL_GPL(blkdev_report_zones);
 
@@ -185,15 +149,11 @@ static inline bool blkdev_allow_reset_all_zones(struct block_device *bdev,
 	if (!blk_queue_zone_resetall(bdev_get_queue(bdev)))
 		return false;
 
-	if (sector || nr_sectors != part_nr_sects_read(bdev->bd_part))
-		return false;
 	/*
-	 * REQ_OP_ZONE_RESET_ALL can be executed only if the block device is
-	 * the entire disk, that is, if the blocks device start offset is 0 and
-	 * its capacity is the same as the entire disk.
+	 * REQ_OP_ZONE_RESET_ALL can be executed only if the number of sectors
+	 * of the applicable zone range is the entire disk.
 	 */
-	return get_start_sect(bdev) == 0 &&
-	       part_nr_sects_read(bdev->bd_part) == get_capacity(bdev->bd_disk);
+	return !sector && nr_sectors == get_capacity(bdev->bd_disk);
 }
 
 /**
@@ -218,6 +178,7 @@ int blkdev_zone_mgmt(struct block_device *bdev, enum req_opf op,
 {
 	struct request_queue *q = bdev_get_queue(bdev);
 	sector_t zone_sectors = blk_queue_zone_sectors(q);
+	sector_t capacity = get_capacity(bdev->bd_disk);
 	sector_t end_sector = sector + nr_sectors;
 	struct bio *bio = NULL;
 	int ret;
@@ -231,7 +192,7 @@ int blkdev_zone_mgmt(struct block_device *bdev, enum req_opf op,
 	if (!op_is_zone_mgmt(op))
 		return -EOPNOTSUPP;
 
-	if (!nr_sectors || end_sector > bdev->bd_part->nr_sects)
+	if (!nr_sectors || end_sector > capacity)
 		/* Out of range */
 		return -EINVAL;
 
@@ -239,8 +200,7 @@ int blkdev_zone_mgmt(struct block_device *bdev, enum req_opf op,
 	if (sector & (zone_sectors - 1))
 		return -EINVAL;
 
-	if ((nr_sectors & (zone_sectors - 1)) &&
-	    end_sector != bdev->bd_part->nr_sects)
+	if ((nr_sectors & (zone_sectors - 1)) && end_sector != capacity)
 		return -EINVAL;
 
 	while (sector < end_sector) {