xemu/hw/ssi.c
Gerd Hoffmann 81a322d4a1 qdev: add return value to init() callbacks.
Sorry folks, but it has to be.  One more of these invasive qdev patches.

We have a serious design bug in the qdev interface:  device init
callbacks can't signal failure because the init() callback has no
return value.  This patch fixes it.

We have already one case in-tree where this is needed:
Try -device virtio-blk-pci (without drive= specified) and watch qemu
segfault.  This patch fixes it.

With usb+scsi being converted to qdev we'll get more devices where the
init callback can fail for various reasons.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-08-27 20:43:28 -05:00

71 lines
1.5 KiB
C

/*
* QEMU Synchronous Serial Interface support
*
* Copyright (c) 2009 CodeSourcery.
* Written by Paul Brook
*
* This code is licenced under the GNU GPL v2.
*/
#include "ssi.h"
struct SSIBus {
BusState qbus;
};
static struct BusInfo ssi_bus_info = {
.name = "SSI",
.size = sizeof(SSIBus),
};
static int ssi_slave_init(DeviceState *dev, DeviceInfo *base_info)
{
SSISlaveInfo *info = container_of(base_info, SSISlaveInfo, qdev);
SSISlave *s = SSI_SLAVE_FROM_QDEV(dev);
SSIBus *bus;
bus = FROM_QBUS(SSIBus, qdev_get_parent_bus(dev));
if (LIST_FIRST(&bus->qbus.children) != dev
|| LIST_NEXT(dev, sibling) != NULL) {
hw_error("Too many devices on SSI bus");
}
s->info = info;
return info->init(s);
}
void ssi_register_slave(SSISlaveInfo *info)
{
assert(info->qdev.size >= sizeof(SSISlave));
info->qdev.init = ssi_slave_init;
info->qdev.bus_info = &ssi_bus_info;
qdev_register(&info->qdev);
}
DeviceState *ssi_create_slave(SSIBus *bus, const char *name)
{
DeviceState *dev;
dev = qdev_create(&bus->qbus, name);
qdev_init(dev);
return dev;
}
SSIBus *ssi_create_bus(DeviceState *parent, const char *name)
{
BusState *bus;
bus = qbus_create(&ssi_bus_info, parent, name);
return FROM_QBUS(SSIBus, bus);
}
uint32_t ssi_transfer(SSIBus *bus, uint32_t val)
{
DeviceState *dev;
SSISlave *slave;
dev = LIST_FIRST(&bus->qbus.children);
if (!dev) {
return 0;
}
slave = SSI_SLAVE_FROM_QDEV(dev);
return slave->info->transfer(slave, val);
}