diff --git a/drivers/block/null_blk.h b/drivers/block/null_blk.h
index 28099be50395b..206309ecc7e4e 100644
--- a/drivers/block/null_blk.h
+++ b/drivers/block/null_blk.h
@@ -44,7 +44,7 @@ struct nullb_device {
 	unsigned int nr_zones;
 	struct blk_zone *zones;
 	sector_t zone_size_sects;
-	spinlock_t zone_lock;
+	unsigned long *zone_locks;
 
 	unsigned long size; /* device size in MB */
 	unsigned long completion_nsec; /* time in ns to complete a request */
diff --git a/drivers/block/null_blk_zoned.c b/drivers/block/null_blk_zoned.c
index 0342696db0ce8..495713d6c989b 100644
--- a/drivers/block/null_blk_zoned.c
+++ b/drivers/block/null_blk_zoned.c
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/vmalloc.h>
+#include <linux/bitmap.h>
 #include "null_blk.h"
 
 #define CREATE_TRACE_POINTS
@@ -45,7 +46,12 @@ int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q)
 	if (!dev->zones)
 		return -ENOMEM;
 
-	spin_lock_init(&dev->zone_lock);
+	dev->zone_locks = bitmap_zalloc(dev->nr_zones, GFP_KERNEL);
+	if (!dev->zone_locks) {
+		kvfree(dev->zones);
+		return -ENOMEM;
+	}
+
 	if (dev->zone_nr_conv >= dev->nr_zones) {
 		dev->zone_nr_conv = dev->nr_zones - 1;
 		pr_info("changed the number of conventional zones to %u",
@@ -106,15 +112,26 @@ int null_register_zoned_dev(struct nullb *nullb)
 
 void null_free_zoned_dev(struct nullb_device *dev)
 {
+	bitmap_free(dev->zone_locks);
 	kvfree(dev->zones);
 }
 
+static inline void null_lock_zone(struct nullb_device *dev, unsigned int zno)
+{
+	wait_on_bit_lock_io(dev->zone_locks, zno, TASK_UNINTERRUPTIBLE);
+}
+
+static inline void null_unlock_zone(struct nullb_device *dev, unsigned int zno)
+{
+	clear_and_wake_up_bit(zno, dev->zone_locks);
+}
+
 int null_report_zones(struct gendisk *disk, sector_t sector,
 		unsigned int nr_zones, report_zones_cb cb, void *data)
 {
 	struct nullb *nullb = disk->private_data;
 	struct nullb_device *dev = nullb->dev;
-	unsigned int first_zone, i;
+	unsigned int first_zone, i, zno;
 	struct blk_zone zone;
 	int error;
 
@@ -125,17 +142,17 @@ int null_report_zones(struct gendisk *disk, sector_t sector,
 	nr_zones = min(nr_zones, dev->nr_zones - first_zone);
 	trace_nullb_report_zones(nullb, nr_zones);
 
-	for (i = 0; i < nr_zones; i++) {
+	zno = first_zone;
+	for (i = 0; i < nr_zones; i++, zno++) {
 		/*
 		 * Stacked DM target drivers will remap the zone information by
 		 * modifying the zone information passed to the report callback.
 		 * So use a local copy to avoid corruption of the device zone
 		 * array.
 		 */
-		spin_lock_irq(&dev->zone_lock);
-		memcpy(&zone, &dev->zones[first_zone + i],
-		       sizeof(struct blk_zone));
-		spin_unlock_irq(&dev->zone_lock);
+		null_lock_zone(dev, zno);
+		memcpy(&zone, &dev->zones[zno], sizeof(struct blk_zone));
+		null_unlock_zone(dev, zno);
 
 		error = cb(&zone, i, data);
 		if (error)
@@ -145,6 +162,10 @@ int null_report_zones(struct gendisk *disk, sector_t sector,
 	return nr_zones;
 }
 
+/*
+ * This is called in the case of memory backing from null_process_cmd()
+ * with the target zone already locked.
+ */
 size_t null_zone_valid_read_len(struct nullb *nullb,
 				sector_t sector, unsigned int len)
 {
@@ -176,10 +197,13 @@ static blk_status_t null_zone_write(struct nullb_cmd *cmd, sector_t sector,
 	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
 		return null_process_cmd(cmd, REQ_OP_WRITE, sector, nr_sectors);
 
+	null_lock_zone(dev, zno);
+
 	switch (zone->cond) {
 	case BLK_ZONE_COND_FULL:
 		/* Cannot write to a full zone */
-		return BLK_STS_IOERR;
+		ret = BLK_STS_IOERR;
+		break;
 	case BLK_ZONE_COND_EMPTY:
 	case BLK_ZONE_COND_IMP_OPEN:
 	case BLK_ZONE_COND_EXP_OPEN:
@@ -197,68 +221,96 @@ static blk_status_t null_zone_write(struct nullb_cmd *cmd, sector_t sector,
 			else
 				cmd->rq->__sector = sector;
 		} else if (sector != zone->wp) {
-			return BLK_STS_IOERR;
+			ret = BLK_STS_IOERR;
+			break;
 		}
 
-		if (zone->wp + nr_sectors > zone->start + zone->capacity)
-			return BLK_STS_IOERR;
+		if (zone->wp + nr_sectors > zone->start + zone->capacity) {
+			ret = BLK_STS_IOERR;
+			break;
+		}
 
 		if (zone->cond != BLK_ZONE_COND_EXP_OPEN)
 			zone->cond = BLK_ZONE_COND_IMP_OPEN;
 
 		ret = null_process_cmd(cmd, REQ_OP_WRITE, sector, nr_sectors);
 		if (ret != BLK_STS_OK)
-			return ret;
+			break;
 
 		zone->wp += nr_sectors;
 		if (zone->wp == zone->start + zone->capacity)
 			zone->cond = BLK_ZONE_COND_FULL;
-		return BLK_STS_OK;
+		ret = BLK_STS_OK;
+		break;
 	default:
 		/* Invalid zone condition */
-		return BLK_STS_IOERR;
+		ret = BLK_STS_IOERR;
 	}
+
+	null_unlock_zone(dev, zno);
+
+	return ret;
 }
 
 static blk_status_t null_zone_mgmt(struct nullb_cmd *cmd, enum req_opf op,
 				   sector_t sector)
 {
 	struct nullb_device *dev = cmd->nq->dev;
-	unsigned int zone_no = null_zone_no(dev, sector);
-	struct blk_zone *zone = &dev->zones[zone_no];
+	unsigned int zone_no;
+	struct blk_zone *zone;
+	blk_status_t ret = BLK_STS_OK;
 	size_t i;
 
-	switch (op) {
-	case REQ_OP_ZONE_RESET_ALL:
+	if (op == REQ_OP_ZONE_RESET_ALL) {
 		for (i = dev->zone_nr_conv; i < dev->nr_zones; i++) {
+			null_lock_zone(dev, i);
 			zone = &dev->zones[i];
 			if (zone->cond != BLK_ZONE_COND_EMPTY) {
 				zone->cond = BLK_ZONE_COND_EMPTY;
 				zone->wp = zone->start;
 				trace_nullb_zone_op(cmd, i, zone->cond);
 			}
+			null_unlock_zone(dev, i);
 		}
 		return BLK_STS_OK;
+	}
+
+	zone_no = null_zone_no(dev, sector);
+	zone = &dev->zones[zone_no];
+
+	null_lock_zone(dev, zone_no);
+
+	switch (op) {
 	case REQ_OP_ZONE_RESET:
-		if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
-			return BLK_STS_IOERR;
+		if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) {
+			ret = BLK_STS_IOERR;
+			break;
+		}
 
 		zone->cond = BLK_ZONE_COND_EMPTY;
 		zone->wp = zone->start;
 		break;
 	case REQ_OP_ZONE_OPEN:
-		if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
-			return BLK_STS_IOERR;
-		if (zone->cond == BLK_ZONE_COND_FULL)
-			return BLK_STS_IOERR;
+		if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) {
+			ret = BLK_STS_IOERR;
+			break;
+		}
+		if (zone->cond == BLK_ZONE_COND_FULL) {
+			ret = BLK_STS_IOERR;
+			break;
+		}
 
 		zone->cond = BLK_ZONE_COND_EXP_OPEN;
 		break;
 	case REQ_OP_ZONE_CLOSE:
-		if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
-			return BLK_STS_IOERR;
-		if (zone->cond == BLK_ZONE_COND_FULL)
-			return BLK_STS_IOERR;
+		if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) {
+			ret = BLK_STS_IOERR;
+			break;
+		}
+		if (zone->cond == BLK_ZONE_COND_FULL) {
+			ret = BLK_STS_IOERR;
+			break;
+		}
 
 		if (zone->wp == zone->start)
 			zone->cond = BLK_ZONE_COND_EMPTY;
@@ -266,27 +318,35 @@ static blk_status_t null_zone_mgmt(struct nullb_cmd *cmd, enum req_opf op,
 			zone->cond = BLK_ZONE_COND_CLOSED;
 		break;
 	case REQ_OP_ZONE_FINISH:
-		if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
-			return BLK_STS_IOERR;
+		if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) {
+			ret = BLK_STS_IOERR;
+			break;
+		}
 
 		zone->cond = BLK_ZONE_COND_FULL;
 		zone->wp = zone->start + zone->len;
+		ret = BLK_STS_OK;
 		break;
 	default:
-		return BLK_STS_NOTSUPP;
+		ret = BLK_STS_NOTSUPP;
+		break;
 	}
 
-	trace_nullb_zone_op(cmd, zone_no, zone->cond);
-	return BLK_STS_OK;
+	if (ret == BLK_STS_OK)
+		trace_nullb_zone_op(cmd, zone_no, zone->cond);
+
+	null_unlock_zone(dev, zone_no);
+
+	return ret;
 }
 
 blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, enum req_opf op,
 				    sector_t sector, sector_t nr_sectors)
 {
-	blk_status_t sts;
 	struct nullb_device *dev = cmd->nq->dev;
+	unsigned int zno = null_zone_no(dev, sector);
+	blk_status_t sts;
 
-	spin_lock_irq(&dev->zone_lock);
 	switch (op) {
 	case REQ_OP_WRITE:
 		sts = null_zone_write(cmd, sector, nr_sectors, false);
@@ -302,9 +362,10 @@ blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, enum req_opf op,
 		sts = null_zone_mgmt(cmd, op, sector);
 		break;
 	default:
+		null_lock_zone(dev, zno);
 		sts = null_process_cmd(cmd, op, sector, nr_sectors);
+		null_unlock_zone(dev, zno);
 	}
-	spin_unlock_irq(&dev->zone_lock);
 
 	return sts;
 }