qemu

guest-loader.c (4948B)

---

 /*
  * Guest Loader
  *
  * Copyright (C) 2020 Linaro
  * Written by Alex Bennée <alex.bennee@linaro.org>
  * (based on the generic-loader by Li Guang <lig.fnst@cn.fujitsu.com>)
  *
  * SPDX-License-Identifier: GPL-2.0-or-later
  *
  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  * See the COPYING file in the top-level directory.
  */
 
 /*
  * Much like the generic-loader this is treated as a special device
  * inside QEMU. However unlike the generic-loader this device is used
  * to load guest images for hypervisors. As part of that process the
  * hypervisor needs to have platform information passed to it by the
  * lower levels of the stack (e.g. firmware/bootloader). If you boot
  * the hypervisor directly you use the guest-loader to load the Dom0
  * or equivalent guest images in the right place in the same way a
  * boot loader would.
  *
  * This is only relevant for full system emulation.
  */
 
 #include "qemu/osdep.h"
 #include "hw/core/cpu.h"
 #include "sysemu/dma.h"
 #include "hw/loader.h"
 #include "hw/qdev-properties.h"
 #include "qapi/error.h"
 #include "qemu/module.h"
 #include "guest-loader.h"
 #include "sysemu/device_tree.h"
 #include "hw/boards.h"
 
 /*
  * Insert some FDT nodes for the loaded blob.
  */
 static void loader_insert_platform_data(GuestLoaderState *s, int size,
                                         Error **errp)
 {
     MachineState *machine = MACHINE(qdev_get_machine());
     void *fdt = machine->fdt;
     g_autofree char *node = g_strdup_printf("/chosen/module@0x%08" PRIx64,
                                             s->addr);
     uint64_t reg_attr[2] = {cpu_to_be64(s->addr), cpu_to_be64(size)};
 
     if (!fdt) {
         error_setg(errp, "Cannot modify FDT fields if the machine has none");
         return;
     }
 
     qemu_fdt_add_subnode(fdt, node);
     qemu_fdt_setprop(fdt, node, "reg", &reg_attr, sizeof(reg_attr));
 
     if (s->kernel) {
         const char *compat[2] = { "multiboot,module", "multiboot,kernel" };
         if (qemu_fdt_setprop_string_array(fdt, node, "compatible",
                                           (char **) &compat,
                                           ARRAY_SIZE(compat)) < 0) {
             error_setg(errp, "couldn't set %s/compatible", node);
             return;
         }
         if (s->args) {
             if (qemu_fdt_setprop_string(fdt, node, "bootargs", s->args) < 0) {
                 error_setg(errp, "couldn't set %s/bootargs", node);
             }
         }
     } else if (s->initrd) {
         const char *compat[2] = { "multiboot,module", "multiboot,ramdisk" };
         if (qemu_fdt_setprop_string_array(fdt, node, "compatible",
                                           (char **) &compat,
                                           ARRAY_SIZE(compat)) < 0) {
             error_setg(errp, "couldn't set %s/compatible", node);
             return;
         }
     }
 }
 
 static void guest_loader_realize(DeviceState *dev, Error **errp)
 {
     GuestLoaderState *s = GUEST_LOADER(dev);
     char *file = s->kernel ? s->kernel : s->initrd;
     int size = 0;
 
     /* Perform some error checking on the user's options */
     if (s->kernel && s->initrd) {
         error_setg(errp, "Cannot specify a kernel and initrd in same stanza");
         return;
     } else if (!s->kernel && !s->initrd)  {
         error_setg(errp, "Need to specify a kernel or initrd image");
         return;
     } else if (!s->addr) {
         error_setg(errp, "Need to specify the address of guest blob");
         return;
     } else if (s->args && !s->kernel) {
         error_setg(errp, "Boot args only relevant to kernel blobs");
     }
 
     /* Default to the maximum size being the machine's ram size */
     size = load_image_targphys_as(file, s->addr, current_machine->ram_size,
                                   NULL);
     if (size < 0) {
         error_setg(errp, "Cannot load specified image %s", file);
         return;
     }
 
     /* Now the image is loaded we need to update the platform data */
     loader_insert_platform_data(s, size, errp);
 }
 
 static Property guest_loader_props[] = {
     DEFINE_PROP_UINT64("addr", GuestLoaderState, addr, 0),
     DEFINE_PROP_STRING("kernel", GuestLoaderState, kernel),
     DEFINE_PROP_STRING("bootargs", GuestLoaderState, args),
     DEFINE_PROP_STRING("initrd", GuestLoaderState, initrd),
     DEFINE_PROP_END_OF_LIST(),
 };
 
 static void guest_loader_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
 
     dc->realize = guest_loader_realize;
     device_class_set_props(dc, guest_loader_props);
     dc->desc = "Guest Loader";
     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 }
 
 static const TypeInfo guest_loader_info = {
     .name = TYPE_GUEST_LOADER,
     .parent = TYPE_DEVICE,
     .instance_size = sizeof(GuestLoaderState),
     .class_init = guest_loader_class_init,
 };
 
 static void guest_loader_register_type(void)
 {
     type_register_static(&guest_loader_info);
 }
 
 type_init(guest_loader_register_type)