[PULL v2 38/38] hw/block/nvme: support Identify NS Attached Controller List

[Klaus Jensen <its@irrelevant.dk>]

From: Minwoo Im <minwoo.im.dev@gmail.com>

Support Identify command for Namespace attached controller list.  This
command handler will traverse the controller instances in the given
subsystem to figure out whether the specified nsid is attached to the
controllers or not.

The 4096bytes Identify data will return with the first entry (16bits)
indicating the number of the controller id entries.  So, the data can
hold up to 2047 entries for the controller ids.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
Tested-by: Klaus Jensen <k.jensen@samsung.com>
[k.jensen: rebased for dma refactor]
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
---
 include/block/nvme.h  |  1 +
 hw/block/nvme.c       | 41 +++++++++++++++++++++++++++++++++++++++++
 hw/block/trace-events |  1 +
 3 files changed, 43 insertions(+)

diff --git a/include/block/nvme.h b/include/block/nvme.h
index 7ee887022aef..372d0f2799fb 100644
--- a/include/block/nvme.h
+++ b/include/block/nvme.h
@@ -971,6 +971,7 @@ enum NvmeIdCns {
     NVME_ID_CNS_CS_NS_ACTIVE_LIST     = 0x07,
     NVME_ID_CNS_NS_PRESENT_LIST       = 0x10,
     NVME_ID_CNS_NS_PRESENT            = 0x11,
+    NVME_ID_CNS_NS_ATTACHED_CTRL_LIST = 0x12,
     NVME_ID_CNS_CS_NS_PRESENT_LIST    = 0x1a,
     NVME_ID_CNS_CS_NS_PRESENT         = 0x1b,
     NVME_ID_CNS_IO_COMMAND_SET        = 0x1c,
diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index cf0bb508aa80..d439e44db839 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -3338,6 +3338,45 @@ static uint16_t nvme_identify_ns(NvmeCtrl *n, NvmeRequest *req, bool active)
     return NVME_INVALID_CMD_SET | NVME_DNR;
 }
 
+static uint16_t nvme_identify_ns_attached_list(NvmeCtrl *n, NvmeRequest *req)
+{
+    NvmeIdentify *c = (NvmeIdentify *)&req->cmd;
+    uint16_t min_id = le16_to_cpu(c->ctrlid);
+    uint16_t list[NVME_CONTROLLER_LIST_SIZE] = {};
+    uint16_t *ids = &list[1];
+    NvmeNamespace *ns;
+    NvmeCtrl *ctrl;
+    int cntlid, nr_ids = 0;
+
+    trace_pci_nvme_identify_ns_attached_list(min_id);
+
+    if (c->nsid == NVME_NSID_BROADCAST) {
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+
+    ns = nvme_subsys_ns(n->subsys, c->nsid);
+    if (!ns) {
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+
+    for (cntlid = min_id; cntlid < ARRAY_SIZE(n->subsys->ctrls); cntlid++) {
+        ctrl = nvme_subsys_ctrl(n->subsys, cntlid);
+        if (!ctrl) {
+            continue;
+        }
+
+        if (!nvme_ns_is_attached(ctrl, ns)) {
+            continue;
+        }
+
+        ids[nr_ids++] = cntlid;
+    }
+
+    list[0] = nr_ids;
+
+    return nvme_c2h(n, (uint8_t *)list, sizeof(list), req);
+}
+
 static uint16_t nvme_identify_ns_csi(NvmeCtrl *n, NvmeRequest *req,
         bool active)
 {
@@ -3540,6 +3579,8 @@ static uint16_t nvme_identify(NvmeCtrl *n, NvmeRequest *req)
         return nvme_identify_ns(n, req, true);
     case NVME_ID_CNS_NS_PRESENT:
         return nvme_identify_ns(n, req, false);
+    case NVME_ID_CNS_NS_ATTACHED_CTRL_LIST:
+        return nvme_identify_ns_attached_list(n, req);
     case NVME_ID_CNS_CS_NS:
         return nvme_identify_ns_csi(n, req, true);
     case NVME_ID_CNS_CS_NS_PRESENT:
diff --git a/hw/block/trace-events b/hw/block/trace-events
index c5dba935a0c1..ef06d2ea7470 100644
--- a/hw/block/trace-events
+++ b/hw/block/trace-events
@@ -66,6 +66,7 @@ pci_nvme_identify(uint16_t cid, uint8_t cns, uint16_t ctrlid, uint8_t csi) "cid
 pci_nvme_identify_ctrl(void) "identify controller"
 pci_nvme_identify_ctrl_csi(uint8_t csi) "identify controller, csi=0x%"PRIx8""
 pci_nvme_identify_ns(uint32_t ns) "nsid %"PRIu32""
+pci_nvme_identify_ns_attached_list(uint16_t cntid) "cntid=%"PRIu16""
 pci_nvme_identify_ns_csi(uint32_t ns, uint8_t csi) "nsid=%"PRIu32", csi=0x%"PRIx8""
 pci_nvme_identify_nslist(uint32_t ns) "nsid %"PRIu32""
 pci_nvme_identify_nslist_csi(uint16_t ns, uint8_t csi) "nsid=%"PRIu16", csi=0x%"PRIx8""
-- 
2.30.1