qdev.c 36.9 KB
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/*
 *  Dynamic device configuration and creation.
 *
 *  Copyright (c) 2009 CodeSourcery
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
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 */

/* The theory here is that it should be possible to create a machine without
   knowledge of specific devices.  Historically board init routines have
   passed a bunch of arguments to each device, requiring the board know
   exactly which device it is dealing with.  This file provides an abstract
   API for device configuration and initialization.  Devices will generally
   inherit from a particular bus (e.g. PCI or I2C) rather than
   this API directly.  */

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#include "net.h"
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#include "qdev.h"
#include "sysemu.h"
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#include "monitor.h"
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static int qdev_hotplug = 0;
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static bool qdev_hot_added = false;
static bool qdev_hot_removed = false;
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/* This is a nasty hack to allow passing a NULL bus to qdev_create.  */
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static BusState *main_system_bus;
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static void main_system_bus_create(void);
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DeviceInfo *device_info_list;
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static BusState *qbus_find_recursive(BusState *bus, const char *name,
                                     const BusInfo *info);
static BusState *qbus_find(const char *path);

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/* Register a new device type.  */
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void qdev_register(DeviceInfo *info)
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{
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    assert(info->size >= sizeof(DeviceState));
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    assert(!info->next);
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    info->next = device_info_list;
    device_info_list = info;
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}

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static DeviceInfo *qdev_find_info(BusInfo *bus_info, const char *name)
{
    DeviceInfo *info;

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    /* first check device names */
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    for (info = device_info_list; info != NULL; info = info->next) {
        if (bus_info && info->bus_info != bus_info)
            continue;
        if (strcmp(info->name, name) != 0)
            continue;
        return info;
    }
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    /* failing that check the aliases */
    for (info = device_info_list; info != NULL; info = info->next) {
        if (bus_info && info->bus_info != bus_info)
            continue;
        if (!info->alias)
            continue;
        if (strcmp(info->alias, name) != 0)
            continue;
        return info;
    }
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    return NULL;
}

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static DeviceState *qdev_create_from_info(BusState *bus, DeviceInfo *info)
{
    DeviceState *dev;
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    Property *prop;
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    assert(bus->info == info->bus_info);
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    dev = g_malloc0(info->size);
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    dev->info = info;
    dev->parent_bus = bus;
    qdev_prop_set_defaults(dev, dev->info->props);
    qdev_prop_set_defaults(dev, dev->parent_bus->info->props);
    qdev_prop_set_globals(dev);
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    QTAILQ_INSERT_HEAD(&bus->children, dev, sibling);
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    if (qdev_hotplug) {
        assert(bus->allow_hotplug);
        dev->hotplugged = 1;
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        qdev_hot_added = true;
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    }
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    dev->instance_id_alias = -1;
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    QTAILQ_INIT(&dev->properties);
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    dev->state = DEV_STATE_CREATED;
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    for (prop = dev->info->props; prop && prop->name; prop++) {
        qdev_property_add_legacy(dev, prop, NULL);
    }

    for (prop = dev->info->bus_info->props; prop && prop->name; prop++) {
        qdev_property_add_legacy(dev, prop, NULL);
    }

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    return dev;
}

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/* Create a new device.  This only initializes the device state structure
   and allows properties to be set.  qdev_init should be called to
   initialize the actual device emulation.  */
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DeviceState *qdev_create(BusState *bus, const char *name)
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{
    DeviceState *dev;

    dev = qdev_try_create(bus, name);
    if (!dev) {
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        if (bus) {
            hw_error("Unknown device '%s' for bus '%s'\n", name,
                     bus->info->name);
        } else {
            hw_error("Unknown device '%s' for default sysbus\n", name);
        }
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    }

    return dev;
}

DeviceState *qdev_try_create(BusState *bus, const char *name)
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{
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    DeviceInfo *info;
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    if (!bus) {
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        bus = sysbus_get_default();
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    }

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    info = qdev_find_info(bus->info, name);
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    if (!info) {
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        return NULL;
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    }

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    return qdev_create_from_info(bus, info);
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}

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static void qdev_print_devinfo(DeviceInfo *info)
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{
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    error_printf("name \"%s\", bus %s",
                 info->name, info->bus_info->name);
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    if (info->alias) {
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        error_printf(", alias \"%s\"", info->alias);
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    }
    if (info->desc) {
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        error_printf(", desc \"%s\"", info->desc);
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    }
    if (info->no_user) {
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        error_printf(", no-user");
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    }
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    error_printf("\n");
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}

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static int set_property(const char *name, const char *value, void *opaque)
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{
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    DeviceState *dev = opaque;

    if (strcmp(name, "driver") == 0)
        return 0;
    if (strcmp(name, "bus") == 0)
        return 0;

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    if (qdev_prop_parse(dev, name, value) == -1) {
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        return -1;
    }
    return 0;
}

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int qdev_device_help(QemuOpts *opts)
{
    const char *driver;
    DeviceInfo *info;
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    Property *prop;
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    driver = qemu_opt_get(opts, "driver");
    if (driver && !strcmp(driver, "?")) {
        for (info = device_info_list; info != NULL; info = info->next) {
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            if (info->no_user) {
                continue;       /* not available, don't show */
            }
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            qdev_print_devinfo(info);
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        }
        return 1;
    }

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    if (!driver || !qemu_opt_get(opts, "?")) {
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        return 0;
    }

    info = qdev_find_info(NULL, driver);
    if (!info) {
        return 0;
    }

    for (prop = info->props; prop && prop->name; prop++) {
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        /*
         * TODO Properties without a parser are just for dirty hacks.
         * qdev_prop_ptr is the only such PropertyInfo.  It's marked
         * for removal.  This conditional should be removed along with
         * it.
         */
        if (!prop->info->parse) {
            continue;           /* no way to set it, don't show */
        }
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        error_printf("%s.%s=%s\n", info->name, prop->name, prop->info->name);
    }
    for (prop = info->bus_info->props; prop && prop->name; prop++) {
        if (!prop->info->parse) {
            continue;           /* no way to set it, don't show */
        }
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        error_printf("%s.%s=%s\n", info->name, prop->name, prop->info->name);
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    }
    return 1;
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}

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static DeviceState *qdev_get_peripheral(void)
{
    static DeviceState *dev;

    if (dev == NULL) {
        dev = qdev_create(NULL, "container");
        qdev_property_add_child(qdev_get_root(), "peripheral", dev, NULL);
        qdev_init_nofail(dev);
    }

    return dev;
}

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static DeviceState *qdev_get_peripheral_anon(void)
{
    static DeviceState *dev;

    if (dev == NULL) {
        dev = qdev_create(NULL, "container");
        qdev_property_add_child(qdev_get_root(), "peripheral-anon", dev, NULL);
        qdev_init_nofail(dev);
    }

    return dev;
}

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DeviceState *qdev_device_add(QemuOpts *opts)
{
    const char *driver, *path, *id;
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    DeviceInfo *info;
    DeviceState *qdev;
    BusState *bus;

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    driver = qemu_opt_get(opts, "driver");
    if (!driver) {
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        qerror_report(QERR_MISSING_PARAMETER, "driver");
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        return NULL;
    }
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    /* find driver */
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    info = qdev_find_info(NULL, driver);
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    if (!info || info->no_user) {
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        qerror_report(QERR_INVALID_PARAMETER_VALUE, "driver", "a driver name");
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        error_printf_unless_qmp("Try with argument '?' for a list.\n");
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        return NULL;
    }

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    /* find bus */
    path = qemu_opt_get(opts, "bus");
    if (path != NULL) {
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        bus = qbus_find(path);
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        if (!bus) {
            return NULL;
        }
        if (bus->info != info->bus_info) {
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            qerror_report(QERR_BAD_BUS_FOR_DEVICE,
                           driver, bus->info->name);
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            return NULL;
        }
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    } else {
        bus = qbus_find_recursive(main_system_bus, NULL, info->bus_info);
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        if (!bus) {
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            qerror_report(QERR_NO_BUS_FOR_DEVICE,
                           info->name, info->bus_info->name);
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            return NULL;
        }
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    }
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    if (qdev_hotplug && !bus->allow_hotplug) {
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        qerror_report(QERR_BUS_NO_HOTPLUG, bus->name);
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        return NULL;
    }
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    /* create device, set properties */
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    qdev = qdev_create_from_info(bus, info);
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    id = qemu_opts_id(opts);
    if (id) {
        qdev->id = id;
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        qdev_property_add_child(qdev_get_peripheral(), qdev->id, qdev, NULL);
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    } else {
        static int anon_count;
        gchar *name = g_strdup_printf("device[%d]", anon_count++);
        qdev_property_add_child(qdev_get_peripheral_anon(), name,
                                qdev, NULL);
        g_free(name);
    }        
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    if (qemu_opt_foreach(opts, set_property, qdev, 1) != 0) {
        qdev_free(qdev);
        return NULL;
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    }
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    if (qdev_init(qdev) < 0) {
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        qerror_report(QERR_DEVICE_INIT_FAILED, driver);
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        return NULL;
    }
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    qdev->opts = opts;
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    return qdev;
}

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/* Initialize a device.  Device properties should be set before calling
   this function.  IRQs and MMIO regions should be connected/mapped after
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   calling this function.
   On failure, destroy the device and return negative value.
   Return 0 on success.  */
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int qdev_init(DeviceState *dev)
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{
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    int rc;

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    assert(dev->state == DEV_STATE_CREATED);
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    rc = dev->info->init(dev, dev->info);
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    if (rc < 0) {
        qdev_free(dev);
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        return rc;
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    }
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    if (dev->info->vmsd) {
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        vmstate_register_with_alias_id(dev, -1, dev->info->vmsd, dev,
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                                       dev->instance_id_alias,
                                       dev->alias_required_for_version);
    }
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    dev->state = DEV_STATE_INITIALIZED;
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    if (dev->hotplugged && dev->info->reset) {
        dev->info->reset(dev);
    }
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    return 0;
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}

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void qdev_set_legacy_instance_id(DeviceState *dev, int alias_id,
                                 int required_for_version)
{
    assert(dev->state == DEV_STATE_CREATED);
    dev->instance_id_alias = alias_id;
    dev->alias_required_for_version = required_for_version;
}

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int qdev_unplug(DeviceState *dev)
{
    if (!dev->parent_bus->allow_hotplug) {
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        qerror_report(QERR_BUS_NO_HOTPLUG, dev->parent_bus->name);
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        return -1;
    }
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    assert(dev->info->unplug != NULL);

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    if (dev->ref != 0) {
        qerror_report(QERR_DEVICE_IN_USE, dev->id?:"");
        return -1;
    }

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    qdev_hot_removed = true;

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    return dev->info->unplug(dev);
}

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static int qdev_reset_one(DeviceState *dev, void *opaque)
{
    if (dev->info->reset) {
        dev->info->reset(dev);
    }

    return 0;
}

BusState *sysbus_get_default(void)
{
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    if (!main_system_bus) {
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        main_system_bus_create();
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    }
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    return main_system_bus;
}

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static int qbus_reset_one(BusState *bus, void *opaque)
{
    if (bus->info->reset) {
        return bus->info->reset(bus);
    }
    return 0;
}

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void qdev_reset_all(DeviceState *dev)
{
    qdev_walk_children(dev, qdev_reset_one, qbus_reset_one, NULL);
}

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void qbus_reset_all_fn(void *opaque)
{
    BusState *bus = opaque;
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    qbus_walk_children(bus, qdev_reset_one, qbus_reset_one, NULL);
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}

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/* can be used as ->unplug() callback for the simple cases */
int qdev_simple_unplug_cb(DeviceState *dev)
{
    /* just zap it */
    qdev_free(dev);
    return 0;
}

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/* Like qdev_init(), but terminate program via error_report() instead of
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   returning an error value.  This is okay during machine creation.
   Don't use for hotplug, because there callers need to recover from
   failure.  Exception: if you know the device's init() callback can't
   fail, then qdev_init_nofail() can't fail either, and is therefore
   usable even then.  But relying on the device implementation that
   way is somewhat unclean, and best avoided.  */
void qdev_init_nofail(DeviceState *dev)
{
    DeviceInfo *info = dev->info;

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    if (qdev_init(dev) < 0) {
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        error_report("Initialization of device %s failed", info->name);
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        exit(1);
    }
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}

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static void qdev_property_del_all(DeviceState *dev)
{
    while (!QTAILQ_EMPTY(&dev->properties)) {
        DeviceProperty *prop = QTAILQ_FIRST(&dev->properties);

        QTAILQ_REMOVE(&dev->properties, prop, node);

        if (prop->release) {
            prop->release(dev, prop->name, prop->opaque);
        }

        g_free(prop->name);
        g_free(prop->type);
        g_free(prop);
    }
}

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/* Unlink device from bus and free the structure.  */
void qdev_free(DeviceState *dev)
{
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    BusState *bus;
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    Property *prop;
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    qdev_property_del_all(dev);

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    if (dev->state == DEV_STATE_INITIALIZED) {
        while (dev->num_child_bus) {
            bus = QLIST_FIRST(&dev->child_bus);
            qbus_free(bus);
        }
        if (dev->info->vmsd)
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            vmstate_unregister(dev, dev->info->vmsd, dev);
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        if (dev->info->exit)
            dev->info->exit(dev);
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        if (dev->opts)
            qemu_opts_del(dev->opts);
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    }
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    QTAILQ_REMOVE(&dev->parent_bus->children, dev, sibling);
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    for (prop = dev->info->props; prop && prop->name; prop++) {
        if (prop->info->free) {
            prop->info->free(dev, prop);
        }
    }
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    g_free(dev);
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}

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void qdev_machine_creation_done(void)
{
    /*
     * ok, initial machine setup is done, starting from now we can
     * only create hotpluggable devices
     */
    qdev_hotplug = 1;
}

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bool qdev_machine_modified(void)
{
    return qdev_hot_added || qdev_hot_removed;
}

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/* Get a character (serial) device interface.  */
CharDriverState *qdev_init_chardev(DeviceState *dev)
{
    static int next_serial;
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    /* FIXME: This function needs to go away: use chardev properties!  */
    return serial_hds[next_serial++];
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}

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BusState *qdev_get_parent_bus(DeviceState *dev)
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{
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    return dev->parent_bus;
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}

void qdev_init_gpio_in(DeviceState *dev, qemu_irq_handler handler, int n)
{
    assert(dev->num_gpio_in == 0);
    dev->num_gpio_in = n;
    dev->gpio_in = qemu_allocate_irqs(handler, dev, n);
}

void qdev_init_gpio_out(DeviceState *dev, qemu_irq *pins, int n)
{
    assert(dev->num_gpio_out == 0);
    dev->num_gpio_out = n;
    dev->gpio_out = pins;
}

qemu_irq qdev_get_gpio_in(DeviceState *dev, int n)
{
    assert(n >= 0 && n < dev->num_gpio_in);
    return dev->gpio_in[n];
}

void qdev_connect_gpio_out(DeviceState * dev, int n, qemu_irq pin)
{
    assert(n >= 0 && n < dev->num_gpio_out);
    dev->gpio_out[n] = pin;
}

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void qdev_set_nic_properties(DeviceState *dev, NICInfo *nd)
{
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    qdev_prop_set_macaddr(dev, "mac", nd->macaddr.a);
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    if (nd->vlan)
        qdev_prop_set_vlan(dev, "vlan", nd->vlan);
    if (nd->netdev)
        qdev_prop_set_netdev(dev, "netdev", nd->netdev);
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    if (nd->nvectors != DEV_NVECTORS_UNSPECIFIED &&
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        qdev_prop_exists(dev, "vectors")) {
        qdev_prop_set_uint32(dev, "vectors", nd->nvectors);
    }
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    nd->instantiated = 1;
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}

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BusState *qdev_get_child_bus(DeviceState *dev, const char *name)
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{
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    BusState *bus;
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    QLIST_FOREACH(bus, &dev->child_bus, sibling) {
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        if (strcmp(name, bus->name) == 0) {
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            return bus;
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        }
    }
    return NULL;
}

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int qbus_walk_children(BusState *bus, qdev_walkerfn *devfn,
                       qbus_walkerfn *busfn, void *opaque)
{
    DeviceState *dev;
    int err;

    if (busfn) {
        err = busfn(bus, opaque);
        if (err) {
            return err;
        }
    }

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    QTAILQ_FOREACH(dev, &bus->children, sibling) {
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        err = qdev_walk_children(dev, devfn, busfn, opaque);
        if (err < 0) {
            return err;
        }
    }

    return 0;
}

int qdev_walk_children(DeviceState *dev, qdev_walkerfn *devfn,
                       qbus_walkerfn *busfn, void *opaque)
{
    BusState *bus;
    int err;

    if (devfn) {
        err = devfn(dev, opaque);
        if (err) {
            return err;
        }
    }

    QLIST_FOREACH(bus, &dev->child_bus, sibling) {
        err = qbus_walk_children(bus, devfn, busfn, opaque);
        if (err < 0) {
            return err;
        }
    }

    return 0;
}

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static BusState *qbus_find_recursive(BusState *bus, const char *name,
                                     const BusInfo *info)
{
    DeviceState *dev;
    BusState *child, *ret;
    int match = 1;

    if (name && (strcmp(bus->name, name) != 0)) {
        match = 0;
    }
    if (info && (bus->info != info)) {
        match = 0;
    }
    if (match) {
        return bus;
    }

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    QTAILQ_FOREACH(dev, &bus->children, sibling) {
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        QLIST_FOREACH(child, &dev->child_bus, sibling) {
633 634 635 636 637 638 639 640 641
            ret = qbus_find_recursive(child, name, info);
            if (ret) {
                return ret;
            }
        }
    }
    return NULL;
}

642
DeviceState *qdev_find_recursive(BusState *bus, const char *id)
643 644 645 646
{
    DeviceState *dev, *ret;
    BusState *child;

647
    QTAILQ_FOREACH(dev, &bus->children, sibling) {
648 649 650 651 652 653 654 655 656 657 658 659
        if (dev->id && strcmp(dev->id, id) == 0)
            return dev;
        QLIST_FOREACH(child, &dev->child_bus, sibling) {
            ret = qdev_find_recursive(child, id);
            if (ret) {
                return ret;
            }
        }
    }
    return NULL;
}

660
static void qbus_list_bus(DeviceState *dev)
661 662 663 664
{
    BusState *child;
    const char *sep = " ";

665 666
    error_printf("child busses at \"%s\":",
                 dev->id ? dev->id : dev->info->name);
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    QLIST_FOREACH(child, &dev->child_bus, sibling) {
668
        error_printf("%s\"%s\"", sep, child->name);
669 670
        sep = ", ";
    }
671
    error_printf("\n");
672 673
}

674
static void qbus_list_dev(BusState *bus)
675 676 677 678
{
    DeviceState *dev;
    const char *sep = " ";

679
    error_printf("devices at \"%s\":", bus->name);
680
    QTAILQ_FOREACH(dev, &bus->children, sibling) {
681
        error_printf("%s\"%s\"", sep, dev->info->name);
682
        if (dev->id)
683
            error_printf("/\"%s\"", dev->id);
684 685
        sep = ", ";
    }
686
    error_printf("\n");
687 688 689 690 691 692
}

static BusState *qbus_find_bus(DeviceState *dev, char *elem)
{
    BusState *child;

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    QLIST_FOREACH(child, &dev->child_bus, sibling) {
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        if (strcmp(child->name, elem) == 0) {
            return child;
        }
    }
    return NULL;
}

static DeviceState *qbus_find_dev(BusState *bus, char *elem)
{
    DeviceState *dev;

    /*
     * try to match in order:
     *   (1) instance id, if present
     *   (2) driver name
     *   (3) driver alias, if present
     */
711
    QTAILQ_FOREACH(dev, &bus->children, sibling) {
712 713 714 715
        if (dev->id  &&  strcmp(dev->id, elem) == 0) {
            return dev;
        }
    }
716
    QTAILQ_FOREACH(dev, &bus->children, sibling) {
717 718 719 720
        if (strcmp(dev->info->name, elem) == 0) {
            return dev;
        }
    }
721
    QTAILQ_FOREACH(dev, &bus->children, sibling) {
722 723 724 725 726 727 728 729 730 731 732
        if (dev->info->alias && strcmp(dev->info->alias, elem) == 0) {
            return dev;
        }
    }
    return NULL;
}

static BusState *qbus_find(const char *path)
{
    DeviceState *dev;
    BusState *bus;
733
    char elem[128];
734 735 736 737 738 739 740 741
    int pos, len;

    /* find start element */
    if (path[0] == '/') {
        bus = main_system_bus;
        pos = 0;
    } else {
        if (sscanf(path, "%127[^/]%n", elem, &len) != 1) {
742 743
            assert(!path[0]);
            elem[0] = len = 0;
744 745 746
        }
        bus = qbus_find_recursive(main_system_bus, elem, NULL);
        if (!bus) {
747
            qerror_report(QERR_BUS_NOT_FOUND, elem);
748 749 750 751 752 753
            return NULL;
        }
        pos = len;
    }

    for (;;) {
754 755 756 757
        assert(path[pos] == '/' || !path[pos]);
        while (path[pos] == '/') {
            pos++;
        }
758 759 760 761 762
        if (path[pos] == '\0') {
            return bus;
        }

        /* find device */
763 764 765
        if (sscanf(path+pos, "%127[^/]%n", elem, &len) != 1) {
            assert(0);
            elem[0] = len = 0;
766 767 768 769
        }
        pos += len;
        dev = qbus_find_dev(bus, elem);
        if (!dev) {
770
            qerror_report(QERR_DEVICE_NOT_FOUND, elem);
771 772 773
            if (!monitor_cur_is_qmp()) {
                qbus_list_dev(bus);
            }
774 775
            return NULL;
        }
776 777 778 779 780

        assert(path[pos] == '/' || !path[pos]);
        while (path[pos] == '/') {
            pos++;
        }
781 782 783 784 785
        if (path[pos] == '\0') {
            /* last specified element is a device.  If it has exactly
             * one child bus accept it nevertheless */
            switch (dev->num_child_bus) {
            case 0:
786
                qerror_report(QERR_DEVICE_NO_BUS, elem);
787 788
                return NULL;
            case 1:
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                return QLIST_FIRST(&dev->child_bus);
790
            default:
791
                qerror_report(QERR_DEVICE_MULTIPLE_BUSSES, elem);
792 793 794
                if (!monitor_cur_is_qmp()) {
                    qbus_list_bus(dev);
                }
795 796 797 798 799
                return NULL;
            }
        }

        /* find bus */
800 801 802
        if (sscanf(path+pos, "%127[^/]%n", elem, &len) != 1) {
            assert(0);
            elem[0] = len = 0;
803 804 805 806
        }
        pos += len;
        bus = qbus_find_bus(dev, elem);
        if (!bus) {
807
            qerror_report(QERR_BUS_NOT_FOUND, elem);
808 809 810
            if (!monitor_cur_is_qmp()) {
                qbus_list_bus(dev);
            }
811 812 813 814 815
            return NULL;
        }
    }
}

816 817
void qbus_create_inplace(BusState *bus, BusInfo *info,
                         DeviceState *parent, const char *name)
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{
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    char *buf;
    int i,len;
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821

822
    bus->info = info;
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823
    bus->parent = parent;
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    if (name) {
        /* use supplied name */
827
        bus->name = g_strdup(name);
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    } else if (parent && parent->id) {
        /* parent device has id -> use it for bus name */
        len = strlen(parent->id) + 16;
831
        buf = g_malloc(len);
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        snprintf(buf, len, "%s.%d", parent->id, parent->num_child_bus);
        bus->name = buf;
    } else {
        /* no id -> use lowercase bus type for bus name */
        len = strlen(info->name) + 16;
837
        buf = g_malloc(len);
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        len = snprintf(buf, len, "%s.%d", info->name,
                       parent ? parent->num_child_bus : 0);
        for (i = 0; i < len; i++)
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Christoph Egger 已提交
841
            buf[i] = qemu_tolower(buf[i]);
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842 843 844
        bus->name = buf;
    }

845
    QTAILQ_INIT(&bus->children);
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846
    if (parent) {
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847
        QLIST_INSERT_HEAD(&parent->child_bus, bus, sibling);
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848
        parent->num_child_bus++;
849 850 851 852
    } else if (bus != main_system_bus) {
        /* TODO: once all bus devices are qdevified,
           only reset handler for main_system_bus should be registered here. */
        qemu_register_reset(qbus_reset_all_fn, bus);
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    }
854 855 856 857 858 859
}

BusState *qbus_create(BusInfo *info, DeviceState *parent, const char *name)
{
    BusState *bus;

860
    bus = g_malloc0(info->size);
861 862
    bus->qdev_allocated = 1;
    qbus_create_inplace(bus, info, parent, name);
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863 864
    return bus;
}
865

I
Isaku Yamahata 已提交
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static void main_system_bus_create(void)
{
    /* assign main_system_bus before qbus_create_inplace()
     * in order to make "if (bus != main_system_bus)" work */
870
    main_system_bus = g_malloc0(system_bus_info.size);
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Isaku Yamahata 已提交
871 872 873 874 875
    main_system_bus->qdev_allocated = 1;
    qbus_create_inplace(main_system_bus, &system_bus_info, NULL,
                        "main-system-bus");
}

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void qbus_free(BusState *bus)
{
    DeviceState *dev;

880
    while ((dev = QTAILQ_FIRST(&bus->children)) != NULL) {
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        qdev_free(dev);
    }
    if (bus->parent) {
        QLIST_REMOVE(bus, sibling);
        bus->parent->num_child_bus--;
886 887 888
    } else {
        assert(bus != main_system_bus); /* main_system_bus is never freed */
        qemu_unregister_reset(qbus_reset_all_fn, bus);
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Gerd Hoffmann 已提交
889
    }
890
    g_free((void*)bus->name);
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891
    if (bus->qdev_allocated) {
892
        g_free(bus);
G
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    }
}

896 897 898
#define qdev_printf(fmt, ...) monitor_printf(mon, "%*s" fmt, indent, "", ## __VA_ARGS__)
static void qbus_print(Monitor *mon, BusState *bus, int indent);

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static void qdev_print_props(Monitor *mon, DeviceState *dev, Property *props,
                             const char *prefix, int indent)
{
    char buf[64];

    if (!props)
        return;
    while (props->name) {
907 908 909 910 911 912
        /*
         * TODO Properties without a print method are just for dirty
         * hacks.  qdev_prop_ptr is the only such PropertyInfo.  It's
         * marked for removal.  The test props->info->print should be
         * removed along with it.
         */
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        if (props->info->print) {
            props->info->print(dev, props, buf, sizeof(buf));
            qdev_printf("%s-prop: %s = %s\n", prefix, props->name, buf);
        }
        props++;
    }
}

921 922 923
static void qdev_print(Monitor *mon, DeviceState *dev, int indent)
{
    BusState *child;
924 925
    qdev_printf("dev: %s, id \"%s\"\n", dev->info->name,
                dev->id ? dev->id : "");
926 927 928 929 930 931 932
    indent += 2;
    if (dev->num_gpio_in) {
        qdev_printf("gpio-in %d\n", dev->num_gpio_in);
    }
    if (dev->num_gpio_out) {
        qdev_printf("gpio-out %d\n", dev->num_gpio_out);
    }
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    qdev_print_props(mon, dev, dev->info->props, "dev", indent);
    qdev_print_props(mon, dev, dev->parent_bus->info->props, "bus", indent);
935 936
    if (dev->parent_bus->info->print_dev)
        dev->parent_bus->info->print_dev(mon, dev, indent);
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    QLIST_FOREACH(child, &dev->child_bus, sibling) {
938 939 940 941 942 943 944 945 946 947
        qbus_print(mon, child, indent);
    }
}

static void qbus_print(Monitor *mon, BusState *bus, int indent)
{
    struct DeviceState *dev;

    qdev_printf("bus: %s\n", bus->name);
    indent += 2;
948
    qdev_printf("type %s\n", bus->info->name);
949
    QTAILQ_FOREACH(dev, &bus->children, sibling) {
950 951 952 953 954 955 956 957 958 959
        qdev_print(mon, dev, indent);
    }
}
#undef qdev_printf

void do_info_qtree(Monitor *mon)
{
    if (main_system_bus)
        qbus_print(mon, main_system_bus, 0);
}
960

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void do_info_qdm(Monitor *mon)
962 963 964 965
{
    DeviceInfo *info;

    for (info = device_info_list; info != NULL; info = info->next) {
966
        qdev_print_devinfo(info);
967 968
    }
}
969

970
int do_device_add(Monitor *mon, const QDict *qdict, QObject **ret_data)
971 972 973
{
    QemuOpts *opts;

974
    opts = qemu_opts_from_qdict(qemu_find_opts("device"), qdict);
975 976 977 978 979 980
    if (!opts) {
        return -1;
    }
    if (!monitor_cur_is_qmp() && qdev_device_help(opts)) {
        qemu_opts_del(opts);
        return 0;
981
    }
982 983 984 985 986
    if (!qdev_device_add(opts)) {
        qemu_opts_del(opts);
        return -1;
    }
    return 0;
987 988
}

989
int do_device_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
990 991 992 993 994 995
{
    const char *id = qdict_get_str(qdict, "id");
    DeviceState *dev;

    dev = qdev_find_recursive(main_system_bus, id);
    if (NULL == dev) {
996 997
        qerror_report(QERR_DEVICE_NOT_FOUND, id);
        return -1;
998
    }
999
    return qdev_unplug(dev);
1000
}
1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011

static int qdev_get_fw_dev_path_helper(DeviceState *dev, char *p, int size)
{
    int l = 0;

    if (dev && dev->parent_bus) {
        char *d;
        l = qdev_get_fw_dev_path_helper(dev->parent_bus->parent, p, size);
        if (dev->parent_bus->info->get_fw_dev_path) {
            d = dev->parent_bus->info->get_fw_dev_path(dev);
            l += snprintf(p + l, size - l, "%s", d);
1012
            g_free(d);
1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032
        } else {
            l += snprintf(p + l, size - l, "%s", dev->info->name);
        }
    }
    l += snprintf(p + l , size - l, "/");

    return l;
}

char* qdev_get_fw_dev_path(DeviceState *dev)
{
    char path[128];
    int l;

    l = qdev_get_fw_dev_path_helper(dev, path, 128);

    path[l-1] = '\0';

    return strdup(path);
}
1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043

void qdev_ref(DeviceState *dev)
{
    dev->ref++;
}

void qdev_unref(DeviceState *dev)
{
    g_assert(dev->ref > 0);
    dev->ref--;
}
1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120

void qdev_property_add(DeviceState *dev, const char *name, const char *type,
                       DevicePropertyAccessor *get, DevicePropertyAccessor *set,
                       DevicePropertyRelease *release,
                       void *opaque, Error **errp)
{
    DeviceProperty *prop = g_malloc0(sizeof(*prop));

    prop->name = g_strdup(name);
    prop->type = g_strdup(type);

    prop->get = get;
    prop->set = set;
    prop->release = release;
    prop->opaque = opaque;

    QTAILQ_INSERT_TAIL(&dev->properties, prop, node);
}

static DeviceProperty *qdev_property_find(DeviceState *dev, const char *name)
{
    DeviceProperty *prop;

    QTAILQ_FOREACH(prop, &dev->properties, node) {
        if (strcmp(prop->name, name) == 0) {
            return prop;
        }
    }

    return NULL;
}

void qdev_property_get(DeviceState *dev, Visitor *v, const char *name,
                       Error **errp)
{
    DeviceProperty *prop = qdev_property_find(dev, name);

    if (prop == NULL) {
        error_set(errp, QERR_PROPERTY_NOT_FOUND, dev->id?:"", name);
        return;
    }

    if (!prop->get) {
        error_set(errp, QERR_PERMISSION_DENIED);
    } else {
        prop->get(dev, v, prop->opaque, name, errp);
    }
}

void qdev_property_set(DeviceState *dev, Visitor *v, const char *name,
                       Error **errp)
{
    DeviceProperty *prop = qdev_property_find(dev, name);

    if (prop == NULL) {
        error_set(errp, QERR_PROPERTY_NOT_FOUND, dev->id?:"", name);
        return;
    }

    if (!prop->set) {
        error_set(errp, QERR_PERMISSION_DENIED);
    } else {
        prop->set(dev, prop->opaque, v, name, errp);
    }
}

const char *qdev_property_get_type(DeviceState *dev, const char *name, Error **errp)
{
    DeviceProperty *prop = qdev_property_find(dev, name);

    if (prop == NULL) {
        error_set(errp, QERR_PROPERTY_NOT_FOUND, dev->id?:"", name);
        return NULL;
    }

    return prop->type;
}
1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196

/**
 * Legacy property handling
 */

static void qdev_get_legacy_property(DeviceState *dev, Visitor *v, void *opaque,
                                     const char *name, Error **errp)
{
    Property *prop = opaque;

    if (prop->info->print) {
        char buffer[1024];
        char *ptr = buffer;

        prop->info->print(dev, prop, buffer, sizeof(buffer));
        visit_type_str(v, &ptr, name, errp);
    } else {
        error_set(errp, QERR_PERMISSION_DENIED);
    }
}

static void qdev_set_legacy_property(DeviceState *dev, Visitor *v, void *opaque,
                                     const char *name, Error **errp)
{
    Property *prop = opaque;

    if (dev->state != DEV_STATE_CREATED) {
        error_set(errp, QERR_PERMISSION_DENIED);
        return;
    }

    if (prop->info->parse) {
        Error *local_err = NULL;
        char *ptr = NULL;

        visit_type_str(v, &ptr, name, &local_err);
        if (!local_err) {
            int ret;
            ret = prop->info->parse(dev, prop, ptr);
            if (ret != 0) {
                error_set(errp, QERR_INVALID_PARAMETER_VALUE,
                          name, prop->info->name);
            }
            g_free(ptr);
        } else {
            error_propagate(errp, local_err);
        }
    } else {
        error_set(errp, QERR_PERMISSION_DENIED);
    }
}

/**
 * @qdev_add_legacy_property - adds a legacy property
 *
 * Do not use this is new code!  Properties added through this interface will
 * be given types in the "legacy<>" type namespace.
 *
 * Legacy properties are always processed as strings.  The format of the string
 * depends on the property type.
 */
void qdev_property_add_legacy(DeviceState *dev, Property *prop,
                              Error **errp)
{
    gchar *type;

    type = g_strdup_printf("legacy<%s>", prop->info->name);

    qdev_property_add(dev, prop->name, type,
                      qdev_get_legacy_property,
                      qdev_set_legacy_property,
                      NULL,
                      prop, errp);

    g_free(type);
}
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DeviceState *qdev_get_root(void)
{
    static DeviceState *qdev_root;

    if (!qdev_root) {
        qdev_root = qdev_create(NULL, "container");
        qdev_init_nofail(qdev_root);
    }

    return qdev_root;
}
1209

1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231
static void qdev_get_child_property(DeviceState *dev, Visitor *v, void *opaque,
                                    const char *name, Error **errp)
{
    DeviceState *child = opaque;
    gchar *path;

    path = qdev_get_canonical_path(child);
    visit_type_str(v, &path, name, errp);
    g_free(path);
}

void qdev_property_add_child(DeviceState *dev, const char *name,
                             DeviceState *child, Error **errp)
{
    gchar *type;

    type = g_strdup_printf("child<%s>", child->info->name);

    qdev_property_add(dev, name, type, qdev_get_child_property,
                      NULL, NULL, child, errp);

    qdev_ref(child);
1232 1233
    g_assert(child->parent == NULL);
    child->parent = dev;
1234 1235 1236 1237

    g_free(type);
}

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Anthony Liguori 已提交
1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311
static void qdev_get_link_property(DeviceState *dev, Visitor *v, void *opaque,
                                   const char *name, Error **errp)
{
    DeviceState **child = opaque;
    gchar *path;

    if (*child) {
        path = qdev_get_canonical_path(*child);
        visit_type_str(v, &path, name, errp);
        g_free(path);
    } else {
        path = (gchar *)"";
        visit_type_str(v, &path, name, errp);
    }
}

static void qdev_set_link_property(DeviceState *dev, Visitor *v, void *opaque,
                                   const char *name, Error **errp)
{
    DeviceState **child = opaque;
    bool ambiguous = false;
    const char *type;
    char *path;

    type = qdev_property_get_type(dev, name, NULL);

    visit_type_str(v, &path, name, errp);

    if (*child) {
        qdev_unref(*child);
    }

    if (strcmp(path, "") != 0) {
        DeviceState *target;

        target = qdev_resolve_path(path, &ambiguous);
        if (target) {
            gchar *target_type;

            target_type = g_strdup_printf("link<%s>", target->info->name);
            if (strcmp(target_type, type) == 0) {
                *child = target;
                qdev_ref(target);
            } else {
                error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, type);
            }

            g_free(target_type);
        } else {
            error_set(errp, QERR_DEVICE_NOT_FOUND, path);
        }
    } else {
        *child = NULL;
    }

    g_free(path);
}

void qdev_property_add_link(DeviceState *dev, const char *name,
                            const char *type, DeviceState **child,
                            Error **errp)
{
    gchar *full_type;

    full_type = g_strdup_printf("link<%s>", type);

    qdev_property_add(dev, name, full_type,
                      qdev_get_link_property,
                      qdev_set_link_property,
                      NULL, child, errp);

    g_free(full_type);
}

1312
gchar *qdev_get_canonical_path(DeviceState *dev)
1313
{
1314 1315
    DeviceState *root = qdev_get_root();
    char *newpath = NULL, *path = NULL;
1316

1317 1318
    while (dev != root) {
        DeviceProperty *prop = NULL;
1319

1320
        g_assert(dev->parent != NULL);
1321

1322 1323 1324 1325
        QTAILQ_FOREACH(prop, &dev->parent->properties, node) {
            if (!strstart(prop->type, "child<", NULL)) {
                continue;
            }
1326

1327 1328 1329 1330 1331 1332 1333 1334 1335 1336
            if (prop->opaque == dev) {
                if (path) {
                    newpath = g_strdup_printf("%s/%s", prop->name, path);
                    g_free(path);
                    path = newpath;
                } else {
                    path = g_strdup(prop->name);
                }
                break;
            }
1337 1338
        }

1339
        g_assert(prop != NULL);
1340

1341
        dev = dev->parent;
1342 1343 1344 1345 1346 1347 1348
    }

    newpath = g_strdup_printf("/%s", path);
    g_free(path);

    return newpath;
}
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static DeviceState *qdev_resolve_abs_path(DeviceState *parent,
                                          gchar **parts,
                                          int index)
{
    DeviceProperty *prop;
    DeviceState *child;

    if (parts[index] == NULL) {
        return parent;
    }

    if (strcmp(parts[index], "") == 0) {
        return qdev_resolve_abs_path(parent, parts, index + 1);
    }

    prop = qdev_property_find(parent, parts[index]);
    if (prop == NULL) {
        return NULL;
    }

    child = NULL;
    if (strstart(prop->type, "link<", NULL)) {
        DeviceState **pchild = prop->opaque;
        if (*pchild) {
            child = *pchild;
        }
    } else if (strstart(prop->type, "child<", NULL)) {
        child = prop->opaque;
    }

    if (!child) {
        return NULL;
    }

    return qdev_resolve_abs_path(child, parts, index + 1);
}

static DeviceState *qdev_resolve_partial_path(DeviceState *parent,
                                              gchar **parts,
                                              bool *ambiguous)
{
    DeviceState *dev;
    DeviceProperty *prop;

    dev = qdev_resolve_abs_path(parent, parts, 0);

    QTAILQ_FOREACH(prop, &parent->properties, node) {
        DeviceState *found;

        if (!strstart(prop->type, "child<", NULL)) {
            continue;
        }

        found = qdev_resolve_partial_path(prop->opaque, parts, ambiguous);
        if (found) {
            if (dev) {
                if (ambiguous) {
                    *ambiguous = true;
                }
                return NULL;
            }
            dev = found;
        }

        if (ambiguous && *ambiguous) {
            return NULL;
        }
    }

    return dev;
}

DeviceState *qdev_resolve_path(const char *path, bool *ambiguous)
{
    bool partial_path = true;
    DeviceState *dev;
    gchar **parts;

    parts = g_strsplit(path, "/", 0);
    if (parts == NULL || parts[0] == NULL) {
        g_strfreev(parts);
        return qdev_get_root();
    }

    if (strcmp(parts[0], "") == 0) {
        partial_path = false;
    }

    if (partial_path) {
        if (ambiguous) {
            *ambiguous = false;
        }
        dev = qdev_resolve_partial_path(qdev_get_root(), parts, ambiguous);
    } else {
        dev = qdev_resolve_abs_path(qdev_get_root(), parts, 1);
    }

    g_strfreev(parts);

    return dev;
}