[PATCH v4 12/14] hw/block/nvme: Add injection of Offline/Read-Only zones

[Dmitry Fomichev <dmitry.fomichev@wdc.com>]

ZNS specification defines two zone conditions for the zones that no
longer can function properly, possibly because of flash wear or other
internal fault. It is useful to be able to "inject" a small number of
such zones for testing purposes.

This commit defines two optional device properties, "offline_zones"
and "rdonly_zones". Users can assign non-zero values to these variables
to specify the number of zones to be initialized as Offline or
Read-Only. The actual number of injected zones may be smaller than the
requested amount - Read-Only and Offline counts are expected to be much
smaller than the total number of zones on a drive.

Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
---
 hw/block/nvme.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 hw/block/nvme.h |  2 ++
 2 files changed, 48 insertions(+)

diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index cfa791aa72..4630be38d7 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -3402,8 +3402,11 @@ static int nvme_init_zone_meta(NvmeCtrl *n, NvmeNamespace *ns,
                                uint64_t capacity)
 {
     NvmeZone *zone;
+    Error *err;
     uint64_t start = 0, zone_size = n->zone_size;
+    uint32_t rnd;
     int i;
+    uint16_t zs;
 
     ns->zone_array = g_malloc0(n->zone_array_size);
     ns->exp_open_zones = g_malloc0(sizeof(NvmeZoneList));
@@ -3434,6 +3437,37 @@ static int nvme_init_zone_meta(NvmeCtrl *n, NvmeNamespace *ns,
         start += zone_size;
     }
 
+    /* If required, make some zones Offline or Read Only */
+
+    for (i = 0; i < n->params.nr_offline_zones; i++) {
+        do {
+            qcrypto_random_bytes(&rnd, sizeof(rnd), &err);
+            rnd %= n->num_zones;
+        } while (rnd < n->params.max_open_zones);
+        zone = &ns->zone_array[rnd];
+        zs = nvme_get_zone_state(zone);
+        if (zs != NVME_ZONE_STATE_OFFLINE) {
+            nvme_set_zone_state(zone, NVME_ZONE_STATE_OFFLINE);
+        } else {
+            i--;
+        }
+    }
+
+    for (i = 0; i < n->params.nr_rdonly_zones; i++) {
+        do {
+            qcrypto_random_bytes(&rnd, sizeof(rnd), &err);
+            rnd %= n->num_zones;
+        } while (rnd < n->params.max_open_zones);
+        zone = &ns->zone_array[rnd];
+        zs = nvme_get_zone_state(zone);
+        if (zs != NVME_ZONE_STATE_OFFLINE &&
+            zs != NVME_ZONE_STATE_READ_ONLY) {
+            nvme_set_zone_state(zone, NVME_ZONE_STATE_READ_ONLY);
+        } else {
+            i--;
+        }
+    }
+
     return 0;
 }
 
@@ -3484,6 +3518,16 @@ static void nvme_zoned_init_ctrl(NvmeCtrl *n, Error **errp)
                     " adjusting", n->params.max_active_zones, nz);
         n->params.max_active_zones = nz;
     }
+    if (n->params.max_open_zones < nz) {
+        if (n->params.nr_offline_zones > nz - n->params.max_open_zones) {
+            n->params.nr_offline_zones = nz - n->params.max_open_zones;
+        }
+        if (n->params.nr_rdonly_zones >
+            nz - n->params.max_open_zones - n->params.nr_offline_zones) {
+            n->params.nr_rdonly_zones =
+                nz - n->params.max_open_zones - n->params.nr_offline_zones;
+        }
+    }
     if (n->params.zd_extension_size) {
         if (n->params.zd_extension_size & 0x3f) {
             error_setg(errp,
@@ -3916,6 +3960,8 @@ static Property nvme_props[] = {
                        params.zd_extension_size, 0),
     DEFINE_PROP_UINT32("max_active", NvmeCtrl, params.max_active_zones, 0),
     DEFINE_PROP_UINT32("max_open", NvmeCtrl, params.max_open_zones, 0),
+    DEFINE_PROP_UINT32("offline_zones", NvmeCtrl, params.nr_offline_zones, 0),
+    DEFINE_PROP_UINT32("rdonly_zones", NvmeCtrl, params.nr_rdonly_zones, 0),
     DEFINE_PROP_BOOL("cross_zone_read", NvmeCtrl, params.cross_zone_read, true),
     DEFINE_PROP_UINT8("fill_pattern", NvmeCtrl, params.fill_pattern, 0),
     DEFINE_PROP_END_OF_LIST(),
diff --git a/hw/block/nvme.h b/hw/block/nvme.h
index 0e82fca815..dea0c12792 100644
--- a/hw/block/nvme.h
+++ b/hw/block/nvme.h
@@ -25,6 +25,8 @@ typedef struct NvmeParams {
     uint32_t    max_active_zones;
     uint32_t    max_open_zones;
     uint32_t    zd_extension_size;
+    uint32_t    nr_offline_zones;
+    uint32_t    nr_rdonly_zones;
 } NvmeParams;
 
 typedef struct NvmeAsyncEvent {
-- 
2.21.0