There is Contrller ID field in Identify Controller data structure and
nvme device has never set this field, 0 by default.

Added a parameter for controller identifier in a NVM subsystem.  This is
reflected to Identify Controller data structrue of the controller.  This
parameter is helpful when a user wants to set up multi-controller in a
NVM subsystem.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
---
 hw/block/nvme.c | 10 ++++++++++
 hw/block/nvme.h |  1 +
 2 files changed, 11 insertions(+)

diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index cf0fe28fe6eb..132e61c0ee7b 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -23,6 +23,7 @@
  *              max_ioqpairs=<N[optional]>, \
  *              aerl=<N[optional]>, aer_max_queued=<N[optional]>, \
  *              mdts=<N[optional]>,zoned.append_size_limit=<N[optional]> \
+ *              cntlid=<N[optional]>
  *      -device nvme-ns,drive=<drive_id>,bus=<bus_name>,nsid=<nsid>,\
  *              zoned=<true|false[optional]>
  *
@@ -50,6 +51,12 @@
  *   completion when there are no outstanding AERs. When the maximum number of
  *   enqueued events are reached, subsequent events will be dropped.
  *
+ * - `cntlid`
+ *   NVM subsystem unique controller identifier (default: 0).  This property
+ *   is used if a user wants to set up multi-controller in a NVM subsystem.
+ *   This value will be reported through Identify Controller data structure
+ *   with a field named CNTLID[79:78].
+ *
  * - `zoned.append_size_limit`
  *   The maximum I/O size in bytes that is allowed in Zone Append command.
  *   The default is 128KiB. Since internally this this value is maintained as
@@ -4275,6 +4282,8 @@ static void nvme_init_ctrl(NvmeCtrl *n, PCIDevice *pci_dev)
 
     n->bar.vs = NVME_SPEC_VER;
     n->bar.intmc = n->bar.intms = 0;
+
+    id->cntlid = n->params.cntlid;
 }
 
 static void nvme_realize(PCIDevice *pci_dev, Error **errp)
@@ -4345,6 +4354,7 @@ static Property nvme_props[] = {
     DEFINE_BLOCK_PROPERTIES(NvmeCtrl, namespace.blkconf),
     DEFINE_PROP_LINK("pmrdev", NvmeCtrl, pmrdev, TYPE_MEMORY_BACKEND,
                      HostMemoryBackend *),
+    DEFINE_PROP_UINT32("cntlid", NvmeCtrl, params.cntlid, 0),
     DEFINE_PROP_STRING("serial", NvmeCtrl, params.serial),
     DEFINE_PROP_UINT32("cmb_size_mb", NvmeCtrl, params.cmb_size_mb, 0),
     DEFINE_PROP_UINT32("num_queues", NvmeCtrl, params.num_queues, 0),
diff --git a/hw/block/nvme.h b/hw/block/nvme.h
index b7fbcca39d9f..6aa9e89ac5a8 100644
--- a/hw/block/nvme.h
+++ b/hw/block/nvme.h
@@ -11,6 +11,7 @@
 
 typedef struct NvmeParams {
     char     *serial;
+    uint32_t cntlid;
     uint32_t num_queues; /* deprecated since 5.1 */
     uint32_t max_ioqpairs;
     uint16_t msix_qsize;
-- 
2.17.1