LXR qemu/ui/util.c

   1/*
   2 * Copyright (C) 2021 Red Hat, Inc.
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of the GNU General Public License as
   6 * published by the Free Software Foundation; either version 2 or
   7 * (at your option) version 3 of the License.
   8 *
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18#include "qemu/osdep.h"
  19
  20#include "hw/pci/pci.h"
  21#include "hw/pci/pci_bus.h"
  22#include "qapi/error.h"
  23#include "ui/console.h"
  24
  25/*
  26 * Recursively (in reverse order) appends addresses of PCI devices as it moves
  27 * up in the PCI hierarchy.
  28 *
  29 * @returns true on success, false when the buffer wasn't large enough
  30 */
  31static bool append_pci_address(char *buf, size_t buf_size, const PCIDevice *pci)
  32{
  33    PCIBus *bus = pci_get_bus(pci);
  34    /*
  35     * equivalent to if (!pci_bus_is_root(bus)), but the function is not built
  36     * with PCI_CONFIG=n, avoid using an #ifdef by checking directly
  37     */
  38    if (bus->parent_dev != NULL) {
  39        append_pci_address(buf, buf_size, bus->parent_dev);
  40    }
  41
  42    size_t len = strlen(buf);
  43    ssize_t written = snprintf(buf + len, buf_size - len, "/%02x.%x",
  44        PCI_SLOT(pci->devfn), PCI_FUNC(pci->devfn));
  45
  46    return written > 0 && written < buf_size - len;
  47}
  48
  49bool qemu_console_fill_device_address(QemuConsole *con,
  50                                      char *device_address,
  51                                      size_t size,
  52                                      Error **errp)
  53{
  54    ERRP_GUARD();
  55    DeviceState *dev = DEVICE(object_property_get_link(OBJECT(con),
  56                                                       "device",
  57                                                       &error_abort));
  58    PCIDevice *pci = (PCIDevice *) object_dynamic_cast(OBJECT(dev),
  59                                                       TYPE_PCI_DEVICE);
  60
  61    if (pci == NULL) {
  62        error_setg(errp, "Setting device address of a display device: "
  63                   "Not a PCI device.");
  64        return false;
  65    }
  66
  67    strncpy(device_address, "pci/0000", size);
  68    if (!append_pci_address(device_address, size, pci)) {
  69        error_setg(errp, "Setting device address of a display device: "
  70                   "Too many PCI devices in the chain.");
  71        return false;
  72    }
  73
  74    return true;
  75}
  76