bdev/zone: add support for max zone append size

Add support in bdev_zone.h for getting the maximum zone append data
transfer size.

Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Change-Id: I61203e64d51601232c6578a090fa52975364c1f3
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/6910
Community-CI: Broadcom CI
Community-CI: Mellanox Build Bot
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>

include/spdk/bdev_module.h

@@ -361,6 +361,11 @@ struct spdk_bdev {
 	 */
 	uint64_t zone_size;
 
+	/**
+	 * Maximum zone append data transfer size (in blocks).
+	 */
+	uint32_t max_zone_append_size;
+
 	/**
 	 * Maximum number of open zones.
 	 */

include/spdk/bdev_zone.h

@@ -84,6 +84,16 @@ struct spdk_bdev_zone_info {
  */
 uint64_t spdk_bdev_get_zone_size(const struct spdk_bdev *bdev);
 
+/**
+ * Get device maximum zone append data transfer size in logical blocks.
+ *
+ * If this value is 0, there is no limit.
+ *
+ * \param bdev Block device to query.
+ * \return Maximum zone append data transfer size for this zoned device in logical blocks.
+ */
+uint32_t spdk_bdev_get_max_zone_append_size(const struct spdk_bdev *bdev);
+
 /**
  * Get device maximum number of open zones.
  *

lib/bdev/bdev_zone.c

@@ -44,6 +44,12 @@ spdk_bdev_get_zone_size(const struct spdk_bdev *bdev)
 	return bdev->zone_size;
 }
 
+uint32_t
+spdk_bdev_get_max_zone_append_size(const struct spdk_bdev *bdev)
+{
+	return bdev->max_zone_append_size;
+}
+
 uint32_t
 spdk_bdev_get_max_open_zones(const struct spdk_bdev *bdev)
 {

lib/bdev/spdk_bdev.map

@@ -143,6 +143,7 @@
 
 	# Public functions in bdev_zone.h
 	spdk_bdev_get_zone_size;
+	spdk_bdev_get_max_zone_append_size;
 	spdk_bdev_get_max_open_zones;
 	spdk_bdev_get_max_active_zones;
 	spdk_bdev_get_optimal_open_zones;

module/bdev/nvme/bdev_ocssd.c

@@ -1305,6 +1305,9 @@ bdev_ocssd_create_bdev(const char *ctrlr_name, const char *bdev_name, uint32_t n
 	nvme_bdev->disk.blockcnt = geometry->num_grp * geometry->num_pu *
 				   geometry->num_chk * geometry->clba;
 	nvme_bdev->disk.zone_size = geometry->clba;
+	/* Since zone appends are emulated using writes, use max io xfer size (but in blocks) */
+	nvme_bdev->disk.max_zone_append_size = spdk_nvme_ns_get_max_io_xfer_size(ns) /
+					       spdk_nvme_ns_get_extended_sector_size(ns);
 	nvme_bdev->disk.max_open_zones = geometry->maxoc;
 	nvme_bdev->disk.optimal_open_zones = geometry->num_grp * geometry->num_pu;
 	nvme_bdev->disk.write_unit_size = geometry->ws_opt;

test/unit/lib/bdev/bdev_zone.c/bdev_zone_ut.c

@@ -254,6 +254,18 @@ test_get_zone_size(void)
 	CU_ASSERT(get_zone_size == 1024 * 4096);
 }
 
+static void
+test_get_max_zone_append_size(void)
+{
+	struct spdk_bdev bdev = {};
+	uint32_t get_max_zone_append_size;
+
+	bdev.max_zone_append_size = 32;
+
+	get_max_zone_append_size = spdk_bdev_get_max_zone_append_size(&bdev);
+	CU_ASSERT(get_max_zone_append_size == 32);
+}
+
 static void
 test_get_max_open_zones(void)
 {
@@ -306,6 +318,7 @@ static void
 test_zone_get_operation(void)
 {
 	test_get_zone_size();
+	test_get_max_zone_append_size();
 	test_get_max_open_zones();
 	test_get_max_active_zones();
 	test_get_optimal_open_zones();

test/unit/lib/bdev/nvme/bdev_ocssd.c/bdev_ocssd_ut.c

@@ -48,6 +48,7 @@ DEFINE_STUB_V(spdk_bdev_module_list_add, (struct spdk_bdev_module *bdev_module))
 DEFINE_STUB(spdk_nvme_ctrlr_is_ocssd_ns, bool, (struct spdk_nvme_ctrlr *ctrlr, uint32_t nsid),
 	    true);
 DEFINE_STUB(spdk_nvme_ns_get_extended_sector_size, uint32_t, (struct spdk_nvme_ns *ns), 4096);
+DEFINE_STUB(spdk_nvme_ns_get_max_io_xfer_size, uint32_t, (struct spdk_nvme_ns *ns), 0);
 DEFINE_STUB(spdk_nvme_ns_is_active, bool, (struct spdk_nvme_ns *ns), true);
 DEFINE_STUB_V(spdk_opal_dev_destruct, (struct spdk_opal_dev *dev));
 DEFINE_STUB_V(spdk_bdev_io_complete_nvme_status, (struct spdk_bdev_io *bdev_io, uint32_t cdw0,