[PATCH v11 01/13] hw/block/nvme: Process controller reset and shutdown differently

[Dmitry Fomichev]

Controller reset ans subsystem shutdown are handled very much the same
in the current code, but some of the steps should be different in these
two cases.

Introduce two new functions, nvme_reset_ctrl() and nvme_shutdown_ctrl(),
to separate some portions of the code from nvme_clear_ctrl(). The steps
that are made different between reset and shutdown are that BAR.CC is not
reset to zero upon the shutdown and namespace data is flushed to
backing storage as a part of shutdown handling, but not upon reset.

Suggested-by: Klaus Jensen <its@irrelevant.dk>
Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
---
 hw/block/nvme-ns.h |  2 +-
 hw/block/nvme-ns.c |  2 +-
 hw/block/nvme.c    | 24 ++++++++++++++++++------
 3 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/hw/block/nvme-ns.h b/hw/block/nvme-ns.h
index 44bf6271b7..ed3d7e65d5 100644
--- a/hw/block/nvme-ns.h
+++ b/hw/block/nvme-ns.h
@@ -73,6 +73,6 @@ typedef struct NvmeCtrl NvmeCtrl;
 
 int nvme_ns_setup(NvmeCtrl *n, NvmeNamespace *ns, Error **errp);
 void nvme_ns_drain(NvmeNamespace *ns);
-void nvme_ns_flush(NvmeNamespace *ns);
+void nvme_ns_shutdown(NvmeNamespace *ns);
 
 #endif /* NVME_NS_H */
diff --git a/hw/block/nvme-ns.c b/hw/block/nvme-ns.c
index 847069a66e..9b95e2ed33 100644
--- a/hw/block/nvme-ns.c
+++ b/hw/block/nvme-ns.c
@@ -130,7 +130,7 @@ void nvme_ns_drain(NvmeNamespace *ns)
     blk_drain(ns->blkconf.blk);
 }
 
-void nvme_ns_flush(NvmeNamespace *ns)
+void nvme_ns_shutdown(NvmeNamespace *ns)
 {
     blk_flush(ns->blkconf.blk);
 }
diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index 59990e00bc..10acb7e7f0 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -2197,6 +2197,20 @@ static void nvme_clear_ctrl(NvmeCtrl *n)
     n->aer_queued = 0;
     n->outstanding_aers = 0;
     n->qs_created = false;
+}
+
+static void nvme_ctrl_reset(NvmeCtrl *n)
+{
+    nvme_clear_ctrl(n);
+    n->bar.cc = 0;
+}
+
+static void nvme_ctrl_shutdown(NvmeCtrl *n)
+{
+    NvmeNamespace *ns;
+    int i;
+
+    nvme_clear_ctrl(n);
 
     for (i = 1; i <= n->num_namespaces; i++) {
         ns = nvme_ns(n, i);
@@ -2204,10 +2218,8 @@ static void nvme_clear_ctrl(NvmeCtrl *n)
             continue;
         }
 
-        nvme_ns_flush(ns);
+        nvme_ns_shutdown(ns);
     }
-
-    n->bar.cc = 0;
 }
 
 static int nvme_start_ctrl(NvmeCtrl *n)
@@ -2374,12 +2386,12 @@ static void nvme_write_bar(NvmeCtrl *n, hwaddr offset, 
uint64_t data,
             }
         } else if (!NVME_CC_EN(data) && NVME_CC_EN(n->bar.cc)) {
             trace_pci_nvme_mmio_stopped();
-            nvme_clear_ctrl(n);
+            nvme_ctrl_reset(n);
             n->bar.csts &= ~NVME_CSTS_READY;
         }
         if (NVME_CC_SHN(data) && !(NVME_CC_SHN(n->bar.cc))) {
             trace_pci_nvme_mmio_shutdown_set();
-            nvme_clear_ctrl(n);
+            nvme_ctrl_shutdown(n);
             n->bar.cc = data;
             n->bar.csts |= NVME_CSTS_SHST_COMPLETE;
         } else if (!NVME_CC_SHN(data) && NVME_CC_SHN(n->bar.cc)) {
@@ -2990,7 +3002,7 @@ static void nvme_exit(PCIDevice *pci_dev)
 {
     NvmeCtrl *n = NVME(pci_dev);
 
-    nvme_clear_ctrl(n);
+    nvme_ctrl_shutdown(n);
     g_free(n->cq);
     g_free(n->sq);
     g_free(n->aer_reqs);
-- 
2.28.0