[PATCH v3 1/4] block: Add zone flags to queue zone prop.

[Javier González]

From: Javier González <javier.gonz at samsung.com>

As the zoned block device will have to deal with features that are
optional for the backend device, add a flag field to inform the block
layer about supported features. This builds on top of
blk_zone_report_flags and extendes to the zone report code.

Signed-off-by: Javier González <javier.gonz at samsung.com>
Signed-off-by: SelvaKumar S <selvakuma.s1 at samsung.com>
Signed-off-by: Kanchan Joshi <joshi.k at samsung.com>
Signed-off-by: Nitesh Shetty <nj.shetty at samsung.com>
---
 block/blk-zoned.c              | 3 ++-
 drivers/block/null_blk_zoned.c | 2 ++
 drivers/nvme/host/zns.c        | 1 +
 drivers/scsi/sd.c              | 2 ++
 include/linux/blkdev.h         | 3 +++
 5 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index 81152a260354..0f156e96e48f 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -312,7 +312,8 @@ int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
 		return ret;
 
 	rep.nr_zones = ret;
-	rep.flags = BLK_ZONE_REP_CAPACITY;
+	rep.flags = q->zone_flags;
+
 	if (copy_to_user(argp, &rep, sizeof(struct blk_zone_report)))
 		return -EFAULT;
 	return 0;
diff --git a/drivers/block/null_blk_zoned.c b/drivers/block/null_blk_zoned.c
index b05832eb21b2..957c2103f240 100644
--- a/drivers/block/null_blk_zoned.c
+++ b/drivers/block/null_blk_zoned.c
@@ -78,6 +78,8 @@ int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q)
 	}
 
 	q->limits.zoned = BLK_ZONED_HM;
+	q->zone_flags = BLK_ZONE_REP_CAPACITY;
+
 	blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q);
 	blk_queue_required_elevator_features(q, ELEVATOR_F_ZBD_SEQ_WRITE);
 
diff --git a/drivers/nvme/host/zns.c b/drivers/nvme/host/zns.c
index c08f6281b614..afe62dc27ff7 100644
--- a/drivers/nvme/host/zns.c
+++ b/drivers/nvme/host/zns.c
@@ -81,6 +81,7 @@ int nvme_update_zone_info(struct gendisk *disk, struct nvme_ns *ns,
 	}
 
 	q->limits.zoned = BLK_ZONED_HM;
+	q->zone_flags = BLK_ZONE_REP_CAPACITY;
 	blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q);
 free_data:
 	kfree(id);
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index d90fefffe31b..b9c920bace28 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -2967,6 +2967,7 @@ static void sd_read_block_characteristics(struct scsi_disk *sdkp)
 	if (sdkp->device->type == TYPE_ZBC) {
 		/* Host-managed */
 		q->limits.zoned = BLK_ZONED_HM;
+		q->zone_flags = BLK_ZONE_REP_CAPACITY;
 	} else {
 		sdkp->zoned = (buffer[8] >> 4) & 3;
 		if (sdkp->zoned == 1 && !disk_has_partitions(sdkp->disk)) {
@@ -2983,6 +2984,7 @@ static void sd_read_block_characteristics(struct scsi_disk *sdkp)
 					  "Drive-managed SMR disk\n");
 		}
 	}
+
 	if (blk_queue_is_zoned(q) && sdkp->first_scan)
 		sd_printk(KERN_NOTICE, sdkp, "Host-%s zoned block device\n",
 		      q->limits.zoned == BLK_ZONED_HM ? "managed" : "aware");
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 8fd900998b4e..3f2e3425fa53 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -512,12 +512,15 @@ struct request_queue {
 	 * Stacking drivers (device mappers) may or may not initialize
 	 * these fields.
 	 *
+	 * Flags represent features as described by blk_zone_report_flags in blkzoned.h
+	 *
 	 * Reads of this information must be protected with blk_queue_enter() /
 	 * blk_queue_exit(). Modifying this information is only allowed while
 	 * no requests are being processed. See also blk_mq_freeze_queue() and
 	 * blk_mq_unfreeze_queue().
 	 */
 	unsigned int		nr_zones;
+	unsigned int		zone_flags;
 	unsigned long		*conv_zones_bitmap;
 	unsigned long		*seq_zones_wlock;
 #endif /* CONFIG_BLK_DEV_ZONED */
-- 
2.17.1