device tree: dont fail operations

When we screw up and issue an FDT command that doesn't work, we really need to
know immediately and usually can't continue to create the machine. To make sure
we don't need to add error checking in all device tree modification code users,
we can just add the fail checks to the qemu abstract functions.
Signed-off-by: NAlexander Graf <agraf@suse.de>

device_tree.c

@@ -72,56 +72,81 @@ fail:
     return NULL;
 }
 
-int qemu_devtree_setprop(void *fdt, const char *node_path,
-                         const char *property, void *val_array, int size)
+static int findnode_nofail(void *fdt, const char *node_path)
 {
     int offset;
 
     offset = fdt_path_offset(fdt, node_path);
-    if (offset < 0)
-        return offset;
+    if (offset < 0) {
+        fprintf(stderr, "%s Couldn't find node %s: %s\n", __func__, node_path,
+                fdt_strerror(offset));
+        exit(1);
+    }
+
+    return offset;
+}
+
+int qemu_devtree_setprop(void *fdt, const char *node_path,
+                         const char *property, void *val_array, int size)
+{
+    int r;
+
+    r = fdt_setprop(fdt, findnode_nofail(fdt, node_path), property, val_array, size);
+    if (r < 0) {
+        fprintf(stderr, "%s: Couldn't set %s/%s: %s\n", __func__, node_path,
+                property, fdt_strerror(r));
+        exit(1);
+    }
 
-    return fdt_setprop(fdt, offset, property, val_array, size);
+    return r;
 }
 
 int qemu_devtree_setprop_cell(void *fdt, const char *node_path,
                               const char *property, uint32_t val)
 {
-    int offset;
+    int r;
 
-    offset = fdt_path_offset(fdt, node_path);
-    if (offset < 0)
-        return offset;
+    r = fdt_setprop_cell(fdt, findnode_nofail(fdt, node_path), property, val);
+    if (r < 0) {
+        fprintf(stderr, "%s: Couldn't set %s/%s = %#08x: %s\n", __func__,
+                node_path, property, val, fdt_strerror(r));
+        exit(1);
+    }
 
-    return fdt_setprop_cell(fdt, offset, property, val);
+    return r;
 }
 
 int qemu_devtree_setprop_string(void *fdt, const char *node_path,
                                 const char *property, const char *string)
 {
-    int offset;
+    int r;
 
-    offset = fdt_path_offset(fdt, node_path);
-    if (offset < 0)
-        return offset;
+    r = fdt_setprop_string(fdt, findnode_nofail(fdt, node_path), property, string);
+    if (r < 0) {
+        fprintf(stderr, "%s: Couldn't set %s/%s = %s: %s\n", __func__,
+                node_path, property, string, fdt_strerror(r));
+        exit(1);
+    }
 
-    return fdt_setprop_string(fdt, offset, property, string);
+    return r;
 }
 
 int qemu_devtree_nop_node(void *fdt, const char *node_path)
 {
-    int offset;
+    int r;
 
-    offset = fdt_path_offset(fdt, node_path);
-    if (offset < 0)
-        return offset;
+    r = fdt_nop_node(fdt, findnode_nofail(fdt, node_path));
+    if (r < 0) {
+        fprintf(stderr, "%s: Couldn't nop node %s: %s\n", __func__, node_path,
+                fdt_strerror(r));
+        exit(1);
+    }
 
-    return fdt_nop_node(fdt, offset);
+    return r;
 }
 
 int qemu_devtree_add_subnode(void *fdt, const char *name)
 {
-    int offset;
     char *dupname = g_strdup(name);
     char *basename = strrchr(dupname, '/');
     int retval;
@@ -133,12 +158,13 @@ int qemu_devtree_add_subnode(void *fdt, const char *name)
     basename[0] = '\0';
     basename++;
 
-    offset = fdt_path_offset(fdt, dupname);
-    if (offset < 0) {
-        return offset;
+    retval = fdt_add_subnode(fdt, findnode_nofail(fdt, dupname), basename);
+    if (retval < 0) {
+        fprintf(stderr, "FDT: Failed to create subnode %s: %s\n", name,
+                fdt_strerror(retval));
+        exit(1);
     }
 
-    retval = fdt_add_subnode(fdt, offset, basename);
     g_free(dupname);
     return retval;
 }