hw/acpi/nvdimm: Don't take address of fields in packed structs

Taking the address of a field in a packed struct is a bad idea, because
it might not be actually aligned enough for that pointer type (and
thus cause a crash on dereference on some host architectures). Newer
versions of clang warn about this. Avoid the bug by not using the
"modify in place" byte swapping functions.

Patch produced with scripts/coccinelle/inplace-byteswaps.cocci.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Message-id: 20181016175236.5840-1-peter.maydell@linaro.org

hw/acpi/nvdimm.c

@@ -581,7 +581,7 @@ static void nvdimm_dsm_func_read_fit(AcpiNVDIMMState *state, NvdimmDsmIn *in,
     int size;
 
     read_fit = (NvdimmFuncReadFITIn *)in->arg3;
-    le32_to_cpus(&read_fit->offset);
+    read_fit->offset = le32_to_cpu(read_fit->offset);
 
     fit = fit_buf->fit;
 
@@ -742,8 +742,8 @@ static void nvdimm_dsm_get_label_data(NVDIMMDevice *nvdimm, NvdimmDsmIn *in,
     int size;
 
     get_label_data = (NvdimmFuncGetLabelDataIn *)in->arg3;
-    le32_to_cpus(&get_label_data->offset);
-    le32_to_cpus(&get_label_data->length);
+    get_label_data->offset = le32_to_cpu(get_label_data->offset);
+    get_label_data->length = le32_to_cpu(get_label_data->length);
 
     nvdimm_debug("Read Label Data: offset %#x length %#x.\n",
                  get_label_data->offset, get_label_data->length);
@@ -781,8 +781,8 @@ static void nvdimm_dsm_set_label_data(NVDIMMDevice *nvdimm, NvdimmDsmIn *in,
 
     set_label_data = (NvdimmFuncSetLabelDataIn *)in->arg3;
 
-    le32_to_cpus(&set_label_data->offset);
-    le32_to_cpus(&set_label_data->length);
+    set_label_data->offset = le32_to_cpu(set_label_data->offset);
+    set_label_data->length = le32_to_cpu(set_label_data->length);
 
     nvdimm_debug("Write Label Data: offset %#x length %#x.\n",
                  set_label_data->offset, set_label_data->length);
@@ -877,9 +877,9 @@ nvdimm_dsm_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
     in = g_new(NvdimmDsmIn, 1);
     cpu_physical_memory_read(dsm_mem_addr, in, sizeof(*in));
 
-    le32_to_cpus(&in->revision);
-    le32_to_cpus(&in->function);
-    le32_to_cpus(&in->handle);
+    in->revision = le32_to_cpu(in->revision);
+    in->function = le32_to_cpu(in->function);
+    in->handle = le32_to_cpu(in->handle);
 
     nvdimm_debug("Revision %#x Handler %#x Function %#x.\n", in->revision,
                  in->handle, in->function);