nvme: add function to get ZNS zone size

Add a function to get the zone size of a zoned namespace.

Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Change-Id: I89429fa2fd36307a8b34bdf91e3251c68596a48c
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/4791
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Community-CI: Broadcom CI

include/spdk/nvme_zns.h

@@ -60,6 +60,18 @@ extern "C" {
  */
 const struct spdk_nvme_zns_ns_data *spdk_nvme_zns_ns_get_data(struct spdk_nvme_ns *ns);
 
+/**
+ * Get the zone size, in bytes, of the given namespace.
+ *
+ * This function is thread safe and can be called at any point while the controller
+ * is attached to the SPDK NVMe driver.
+ *
+ * \param ns Namespace to query.
+ *
+ * \return the zone size of the given namespace in bytes.
+ */
+uint64_t spdk_nvme_zns_ns_get_zone_size(struct spdk_nvme_ns *ns);
+
 /**
  * Get the Zoned Namespace Command Set Specific Identify Controller data
  * as defined by the NVMe Zoned Namespace Command Set Specification.

lib/nvme/nvme_zns.c

@@ -39,6 +39,15 @@ spdk_nvme_zns_ns_get_data(struct spdk_nvme_ns *ns)
 	return ns->ctrlr->nsdata_zns[ns->id - 1];
 }
 
+uint64_t
+spdk_nvme_zns_ns_get_zone_size(struct spdk_nvme_ns *ns)
+{
+	const struct spdk_nvme_zns_ns_data *nsdata_zns = spdk_nvme_zns_ns_get_data(ns);
+	const struct spdk_nvme_ns_data *nsdata = spdk_nvme_ns_get_data(ns);
+
+	return nsdata_zns->lbafe[nsdata->flbas.format].zsze * spdk_nvme_ns_get_sector_size(ns);
+}
+
 const struct spdk_nvme_zns_ctrlr_data *
 spdk_nvme_zns_ctrlr_get_data(struct spdk_nvme_ctrlr *ctrlr)
 {

lib/nvme/spdk_nvme.map

@@ -160,6 +160,7 @@
 
 	# public functions from nvme_zns.h
 	spdk_nvme_zns_ns_get_data;
+	spdk_nvme_zns_ns_get_zone_size;
 	spdk_nvme_zns_ctrlr_get_data;
 	spdk_nvme_zns_close_zone;
 	spdk_nvme_zns_finish_zone;