Commit 73064edfb864 ("hw/nvme: flexible data placement emulation")
intorudced NVMe FDP feature to nvme-subsys and nvme-ctrl with a
single endurance group #1 supported.  This means that controller should
return proper identify data to host with Identify Endurance Group List
(CNS 19h).  But, yes, only just for the endurance group #1.  This patch
allows host applications to ask for which endurance group is available
and utilize FDP through that endurance group.

Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
Signed-off-by: Minwoo Im <minwoo.im@samsung.com>
---
 hw/nvme/ctrl.c       | 22 ++++++++++++++++++++++
 include/block/nvme.h |  1 +
 2 files changed, 23 insertions(+)

diff --git a/hw/nvme/ctrl.c b/hw/nvme/ctrl.c
index 127c3d2383..18672f6619 100644
--- a/hw/nvme/ctrl.c
+++ b/hw/nvme/ctrl.c
@@ -5629,6 +5629,26 @@ static uint16_t nvme_identify_nslist_csi(NvmeCtrl *n, NvmeRequest *req,
     return nvme_c2h(n, list, data_len, req);
 }
 
+static uint16_t nvme_endurance_group_list(NvmeCtrl *n, NvmeRequest *req)
+{
+    uint16_t list[NVME_CONTROLLER_LIST_SIZE] = {};
+    uint16_t *nr_ids = &list[0];
+    uint16_t *ids = &list[1];
+    uint16_t endgid = le32_to_cpu(req->cmd.cdw11) & 0xffff;
+
+    /*
+     * The current nvme-subsys only supports Endurance Group #1.
+     */
+    if (!endgid) {
+        *nr_ids = 1;
+        ids[0] = 1;
+    } else {
+        *nr_ids = 0;
+    }
+
+    return nvme_c2h(n, list, sizeof(list), req);
+}
+
 static uint16_t nvme_identify_ns_descr_list(NvmeCtrl *n, NvmeRequest *req)
 {
     NvmeNamespace *ns;
@@ -5744,6 +5764,8 @@ static uint16_t nvme_identify(NvmeCtrl *n, NvmeRequest *req)
         return nvme_identify_nslist(n, req, false);
     case NVME_ID_CNS_CS_NS_ACTIVE_LIST:
         return nvme_identify_nslist_csi(n, req, true);
+    case NVME_ID_CNS_ENDURANCE_GROUP_LIST:
+        return nvme_endurance_group_list(n, req);
     case NVME_ID_CNS_CS_NS_PRESENT_LIST:
         return nvme_identify_nslist_csi(n, req, false);
     case NVME_ID_CNS_NS_DESCR_LIST:
diff --git a/include/block/nvme.h b/include/block/nvme.h
index bb231d0b9a..7c77d38174 100644
--- a/include/block/nvme.h
+++ b/include/block/nvme.h
@@ -1074,6 +1074,7 @@ enum NvmeIdCns {
     NVME_ID_CNS_CTRL_LIST             = 0x13,
     NVME_ID_CNS_PRIMARY_CTRL_CAP      = 0x14,
     NVME_ID_CNS_SECONDARY_CTRL_LIST   = 0x15,
+    NVME_ID_CNS_ENDURANCE_GROUP_LIST  = 0x19,
     NVME_ID_CNS_CS_NS_PRESENT_LIST    = 0x1a,
     NVME_ID_CNS_CS_NS_PRESENT         = 0x1b,
     NVME_ID_CNS_IO_COMMAND_SET        = 0x1c,
-- 
2.34.1