[PATCH v3 8/9] hw/block/nvme: track and enforce zone resources

[Klaus Jensen <its@irrelevant.dk>]

From: Klaus Jensen <k.jensen@samsung.com>

Track number of open/active resources.

Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
---
 docs/specs/nvme.txt  |  6 ++++
 hw/block/nvme-ns.h   |  7 +++++
 include/block/nvme.h |  2 ++
 hw/block/nvme-ns.c   | 25 +++++++++++++++--
 hw/block/nvme.c      | 66 +++++++++++++++++++++++++++++++++++++++++++-
 5 files changed, 102 insertions(+), 4 deletions(-)

diff --git a/docs/specs/nvme.txt b/docs/specs/nvme.txt
index 80cb34406255..03bb4d9516b4 100644
--- a/docs/specs/nvme.txt
+++ b/docs/specs/nvme.txt
@@ -14,6 +14,12 @@ The nvme device (-device nvme) emulates an NVM Express Controller.
      zns.zcap; if the zone capacity is a power of two, the zone size will be
      set to that, otherwise it will default to the next power of two.
 
+  `zns.mar`; Specifies the number of active resources available. This is a 0s
+     based value.
+
+  `zns.mor`; Specifies the number of open resources available. This is a 0s
+     based value.
+
 
 Reference Specifications
 ------------------------
diff --git a/hw/block/nvme-ns.h b/hw/block/nvme-ns.h
index a273e7f7ed4b..3d0269eef6f0 100644
--- a/hw/block/nvme-ns.h
+++ b/hw/block/nvme-ns.h
@@ -28,6 +28,8 @@ typedef struct NvmeNamespaceParams {
         uint64_t zcap;
         uint64_t zsze;
         uint8_t  zdes;
+        uint32_t mar;
+        uint32_t mor;
     } zns;
 } NvmeNamespaceParams;
 
@@ -58,6 +60,11 @@ typedef struct NvmeNamespace {
         NvmeZone           *zones;
         NvmeZoneDescriptor *zd;
         uint8_t            *zde;
+
+        struct {
+            uint32_t open;
+            uint32_t active;
+        } resources;
     } zns;
 } NvmeNamespace;
 
diff --git a/include/block/nvme.h b/include/block/nvme.h
index aecefefd43b6..4ca5f3fb15eb 100644
--- a/include/block/nvme.h
+++ b/include/block/nvme.h
@@ -775,6 +775,8 @@ enum NvmeStatusCodes {
     NVME_ZONE_IS_READ_ONLY      = 0x01ba,
     NVME_ZONE_IS_OFFLINE        = 0x01bb,
     NVME_ZONE_INVALID_WRITE     = 0x01bc,
+    NVME_TOO_MANY_ACTIVE_ZONES  = 0x01bd,
+    NVME_TOO_MANY_OPEN_ZONES    = 0x01be,
     NVME_INVALID_ZONE_STATE_TRANSITION = 0x01bf,
     NVME_WRITE_FAULT            = 0x0280,
     NVME_UNRECOVERED_READ       = 0x0281,
diff --git a/hw/block/nvme-ns.c b/hw/block/nvme-ns.c
index 0922b67dd6d8..a01cc5eeb445 100644
--- a/hw/block/nvme-ns.c
+++ b/hw/block/nvme-ns.c
@@ -92,8 +92,8 @@ static void nvme_ns_init_zoned(NvmeNamespace *ns)
         ns->zns.zde = g_malloc0_n(ns->zns.num_zones, nvme_ns_zdes_bytes(ns));
     }
 
-    id_ns_zns->mar = 0xffffffff;
-    id_ns_zns->mor = 0xffffffff;
+    id_ns_zns->mar = cpu_to_le32(ns->params.zns.mar);
+    id_ns_zns->mor = cpu_to_le32(ns->params.zns.mor);
 }
 
 static void nvme_ns_init(NvmeNamespace *ns)
@@ -130,6 +130,11 @@ static void nvme_ns_init(NvmeNamespace *ns)
 
 void nvme_ns_zns_init_zone_state(NvmeNamespace *ns)
 {
+    ns->zns.resources.active = ns->params.zns.mar != 0xffffffff ?
+        ns->params.zns.mar + 1 : ns->zns.num_zones;
+    ns->zns.resources.open = ns->params.zns.mor != 0xffffffff ?
+        ns->params.zns.mor + 1 : ns->zns.num_zones;
+
     for (int i = 0; i < ns->zns.num_zones; i++) {
         NvmeZone *zone = &ns->zns.zones[i];
         zone->zd = &ns->zns.zd[i];
@@ -148,9 +153,15 @@ void nvme_ns_zns_init_zone_state(NvmeNamespace *ns)
             if (nvme_wp(zone) == nvme_zslba(zone) &&
                 !(zone->zd->za & NVME_ZA_ZDEV)) {
                 nvme_zs_set(zone, NVME_ZS_ZSE);
+                break;
             }
 
-            break;
+            if (ns->zns.resources.active) {
+                ns->zns.resources.active--;
+                break;
+            }
+
+            /* fallthrough */
 
         case NVME_ZS_ZSIO:
         case NVME_ZS_ZSEO:
@@ -207,6 +218,12 @@ static int nvme_ns_check_constraints(NvmeNamespace *ns, Error **errp)
             return -1;
         }
 
+        if (ns->params.zns.mor > ns->params.zns.mar) {
+            error_setg(errp, "maximum open resources (zns.mor) must be less "
+                       "than or equal to maximum active resources (zns.mar)");
+            return -1;
+        }
+
         break;
 
     default:
@@ -272,6 +289,8 @@ static Property nvme_ns_props[] = {
     DEFINE_PROP_UINT64("zns.zcap", NvmeNamespace, params.zns.zcap, 0),
     DEFINE_PROP_UINT64("zns.zsze", NvmeNamespace, params.zns.zsze, 0),
     DEFINE_PROP_UINT8("zns.zdes", NvmeNamespace, params.zns.zdes, 0),
+    DEFINE_PROP_UINT32("zns.mar", NvmeNamespace, params.zns.mar, 0xffffffff),
+    DEFINE_PROP_UINT32("zns.mor", NvmeNamespace, params.zns.mor, 0xffffffff),
     DEFINE_PROP_END_OF_LIST(),
 };
 
diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index 947554c48b35..cc637b3a68e9 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -1119,6 +1119,40 @@ static uint16_t nvme_zrm_transition(NvmeNamespace *ns, NvmeZone *zone,
 
     switch (from) {
     case NVME_ZS_ZSE:
+        switch (to) {
+        case NVME_ZS_ZSF:
+        case NVME_ZS_ZSRO:
+        case NVME_ZS_ZSO:
+            break;
+
+        case NVME_ZS_ZSC:
+            if (!ns->zns.resources.active) {
+                return NVME_TOO_MANY_ACTIVE_ZONES;
+            }
+
+            ns->zns.resources.active--;
+
+            break;
+
+        case NVME_ZS_ZSIO:
+        case NVME_ZS_ZSEO:
+            if (!ns->zns.resources.active) {
+                return NVME_TOO_MANY_ACTIVE_ZONES;
+            }
+
+            if (!ns->zns.resources.open) {
+                return NVME_TOO_MANY_OPEN_ZONES;
+            }
+
+            ns->zns.resources.active--;
+            ns->zns.resources.open--;
+
+            break;
+
+        default:
+            return NVME_INVALID_ZONE_STATE_TRANSITION | NVME_DNR;
+        }
+
         break;
 
     case NVME_ZS_ZSIO:
@@ -1137,7 +1171,13 @@ static uint16_t nvme_zrm_transition(NvmeNamespace *ns, NvmeZone *zone,
         case NVME_ZS_ZSEO:
         case NVME_ZS_ZSF:
         case NVME_ZS_ZSRO:
+            ns->zns.resources.active++;
+
+            /* fallthrough */
+
         case NVME_ZS_ZSC:
+            ns->zns.resources.open++;
+
             break;
 
         default:
@@ -1160,8 +1200,18 @@ static uint16_t nvme_zrm_transition(NvmeNamespace *ns, NvmeZone *zone,
 
         case NVME_ZS_ZSF:
         case NVME_ZS_ZSRO:
+            ns->zns.resources.active++;
+
+            break;
+
         case NVME_ZS_ZSIO:
         case NVME_ZS_ZSEO:
+            if (!ns->zns.resources.open) {
+                return NVME_TOO_MANY_OPEN_ZONES;
+            }
+
+            ns->zns.resources.open--;
+
             break;
 
         default:
@@ -1492,7 +1542,7 @@ static uint16_t nvme_zone_mgmt_send_all(NvmeCtrl *n, NvmeRequest *req)
     NvmeZoneManagementSendCmd *send = (NvmeZoneManagementSendCmd *) &req->cmd;
     NvmeNamespace *ns = req->ns;
     NvmeZone *zone;
-    int *countp = NULL;
+    int count, *countp = NULL;
     uint16_t status = NVME_SUCCESS;
 
     trace_pci_nvme_zone_mgmt_send_all(nvme_cid(req), nvme_nsid(ns), send->zsa);
@@ -1541,6 +1591,20 @@ static uint16_t nvme_zone_mgmt_send_all(NvmeCtrl *n, NvmeRequest *req)
         break;
 
     case NVME_CMD_ZONE_MGMT_SEND_OPEN:
+        count = 0;
+
+        for (int i = 0; i < ns->zns.num_zones; i++) {
+            zone = &ns->zns.zones[i];
+
+            if (nvme_zs(zone) == NVME_ZS_ZSC) {
+                count++;
+            }
+        }
+
+        if (count > ns->zns.resources.open) {
+            return NVME_TOO_MANY_OPEN_ZONES;
+        }
+
         for (int i = 0; i < ns->zns.num_zones; i++) {
             zone = &ns->zns.zones[i];
 
-- 
2.28.0