nvdimm acpi: prebuild nvdimm devices for available slots

For each NVDIMM present or intended to be supported by platform,
platform firmware also exposes an ACPI Namespace Device under
the root device

So it builds nvdimm devices for all slots to support vNVDIMM hotplug

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

3 files changed, 27 insertions, 19 deletions

diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c
index bb896c9dcc..b8a2e6269a 100644
--- a/hw/acpi/nvdimm.c
+++ b/hw/acpi/nvdimm.c
@@ -961,12 +961,11 @@ static void nvdimm_build_device_dsm(Aml *dev, uint32_t handle)
     aml_append(dev, method);
 }
 
-static void nvdimm_build_nvdimm_devices(GSList *device_list, Aml *root_dev)
+static void nvdimm_build_nvdimm_devices(Aml *root_dev, uint32_t ram_slots)
 {
-    for (; device_list; device_list = device_list->next) {
-        DeviceState *dev = device_list->data;
-        int slot = object_property_get_int(OBJECT(dev), PC_DIMM_SLOT_PROP,
-                                           NULL);
+    uint32_t slot;
+
+    for (slot = 0; slot < ram_slots; slot++) {
         uint32_t handle = nvdimm_slot_to_handle(slot);
         Aml *nvdimm_dev;
 
@@ -987,9 +986,9 @@ static void nvdimm_build_nvdimm_devices(GSList *device_list, Aml *root_dev)
     }
 }
 
-static void nvdimm_build_ssdt(GSList *device_list, GArray *table_offsets,
-                              GArray *table_data, BIOSLinker *linker,
-                              GArray *dsm_dma_arrea)
+static void nvdimm_build_ssdt(GArray *table_offsets, GArray *table_data,
+                              BIOSLinker *linker, GArray *dsm_dma_arrea,
+                              uint32_t ram_slots)
 {
     Aml *ssdt, *sb_scope, *dev;
     int mem_addr_offset, nvdimm_ssdt;
@@ -1021,7 +1020,7 @@ static void nvdimm_build_ssdt(GSList *device_list, GArray *table_offsets,
     /* 0 is reserved for root device. */
     nvdimm_build_device_dsm(dev, 0);
 
-    nvdimm_build_nvdimm_devices(device_list, dev);
+    nvdimm_build_nvdimm_devices(dev, ram_slots);
 
     aml_append(sb_scope, dev);
     aml_append(ssdt, sb_scope);
@@ -1046,17 +1045,25 @@ static void nvdimm_build_ssdt(GSList *device_list, GArray *table_offsets,
 }
 
 void nvdimm_build_acpi(GArray *table_offsets, GArray *table_data,
-                       BIOSLinker *linker, GArray *dsm_dma_arrea)
+                       BIOSLinker *linker, GArray *dsm_dma_arrea,
+                       uint32_t ram_slots)
 {
     GSList *device_list;
 
-    /* no NVDIMM device is plugged. */
     device_list = nvdimm_get_plugged_device_list();
-    if (!device_list) {
-        return;
+
+    /* NVDIMM device is plugged. */
+    if (device_list) {
+        nvdimm_build_nfit(device_list, table_offsets, table_data, linker);
+        g_slist_free(device_list);
+    }
+
+    /*
+     * NVDIMM device is allowed to be plugged only if there is available
+     * slot.
+     */
+    if (ram_slots) {
+        nvdimm_build_ssdt(table_offsets, table_data, linker, dsm_dma_arrea,
+                          ram_slots);
     }
-    nvdimm_build_nfit(device_list, table_offsets, table_data, linker);
-    nvdimm_build_ssdt(device_list, table_offsets, table_data, linker,
-                      dsm_dma_arrea);
-    g_slist_free(device_list);
 }
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 93be96f89c..cec4b4e848 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -2811,7 +2811,7 @@ void acpi_build(AcpiBuildTables *tables, MachineState *machine)
     }
     if (pcms->acpi_nvdimm_state.is_enabled) {
         nvdimm_build_acpi(table_offsets, tables_blob, tables->linker,
-                          pcms->acpi_nvdimm_state.dsm_mem);
+                          pcms->acpi_nvdimm_state.dsm_mem, machine->ram_slots);
     }
 
     /* Add tables supplied by user (if any) */
diff --git a/include/hw/mem/nvdimm.h b/include/hw/mem/nvdimm.h
index 1cfe9e01c4..63a2b20fa9 100644
--- a/include/hw/mem/nvdimm.h
+++ b/include/hw/mem/nvdimm.h
@@ -112,5 +112,6 @@ typedef struct AcpiNVDIMMState AcpiNVDIMMState;
 void nvdimm_init_acpi_state(AcpiNVDIMMState *state, MemoryRegion *io,
                             FWCfgState *fw_cfg, Object *owner);
 void nvdimm_build_acpi(GArray *table_offsets, GArray *table_data,
-                       BIOSLinker *linker, GArray *dsm_dma_arrea);
+                       BIOSLinker *linker, GArray *dsm_dma_arrea,
+                       uint32_t ram_slots);
 #endif