[PATCH] hw/nvme: add param to control auto zone transitioning to zone state closed

[Niklas Cassel <Niklas.Cassel@wdc.com>]

From: Niklas Cassel <niklas.cassel@wdc.com>

In the Zoned Namespace Command Set Specification, chapter
2.5.1 Managing resources

"The controller may transition zones in the ZSIO:Implicitly Opened state
to the ZSC:Closed state for resource management purposes."

The word may in this sentence means that automatically transitioning
an implicitly opened zone to closed is completely optional.

Add a new parameter so that the user can control if this automatic
transitioning should be performed or not.

Being able to control this can help with verifying that e.g. a user-space
program behaves properly even without this optional ZNS feature.

The default value is set to true, in order to not change the existing
behavior.

Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
---
 hw/nvme/ctrl.c | 9 ++++++++-
 hw/nvme/ns.c   | 2 ++
 hw/nvme/nvme.h | 1 +
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/hw/nvme/ctrl.c b/hw/nvme/ctrl.c
index 40a7efcea9..d00f0297a5 100644
--- a/hw/nvme/ctrl.c
+++ b/hw/nvme/ctrl.c
@@ -141,6 +141,11 @@
  *
  *     zoned.cross_read=<enable RAZB, default: false>
  *         Setting this property to true enables Read Across Zone Boundaries.
+ *
+ *     zoned.auto_transition=<enable auto resource management, default: true>
+ *         Indicates if zones in zone state implicitly opened can be
+ *         automatically transitioned to zone state closed for resource
+ *         management purposes.
  */
 
 #include "qemu/osdep.h"
@@ -1699,7 +1704,9 @@ static uint16_t nvme_zrm_open_flags(NvmeNamespace *ns, NvmeZone *zone,
         /* fallthrough */
 
     case NVME_ZONE_STATE_CLOSED:
-        nvme_zrm_auto_transition_zone(ns);
+        if (ns->params.auto_transition_zones) {
+            nvme_zrm_auto_transition_zone(ns);
+        }
         status = nvme_aor_check(ns, act, 1);
         if (status) {
             return status;
diff --git a/hw/nvme/ns.c b/hw/nvme/ns.c
index 3fec9c6273..31dee43d30 100644
--- a/hw/nvme/ns.c
+++ b/hw/nvme/ns.c
@@ -531,6 +531,8 @@ static Property nvme_ns_props[] = {
                        params.max_open_zones, 0),
     DEFINE_PROP_UINT32("zoned.descr_ext_size", NvmeNamespace,
                        params.zd_extension_size, 0),
+    DEFINE_PROP_BOOL("zoned.auto_transition", NvmeNamespace,
+                     params.auto_transition_zones, true),
     DEFINE_PROP_END_OF_LIST(),
 };
 
diff --git a/hw/nvme/nvme.h b/hw/nvme/nvme.h
index 81a35cda14..bd86054db2 100644
--- a/hw/nvme/nvme.h
+++ b/hw/nvme/nvme.h
@@ -100,6 +100,7 @@ typedef struct NvmeNamespaceParams {
     uint32_t max_active_zones;
     uint32_t max_open_zones;
     uint32_t zd_extension_size;
+    bool     auto_transition_zones;
 } NvmeNamespaceParams;
 
 typedef struct NvmeNamespace {
-- 
2.31.1