virtio-serial: Fix endianness bug in the config space

The virtio serial specification requres that the values in the config
space are encoded in native endian of the guest.

The qemu virtio-serial code did not do conversion to the guest endian
format what caused problems when host and guest use different format.

This patch corrects the qemu side, correctly doing host-native <->
guest-native conversions when accessing the config space. This won't
break any setups that aren't already broken, and fixes the case
of different host and guest endianness.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
This commit is contained in:
Alexey Kardashevskiy 2011-04-19 12:03:46 +10:00 committed by Amit Shah
parent da7d998bbb
commit 5c1c9bb24b

View File

@ -494,7 +494,7 @@ static void virtio_serial_save(QEMUFile *f, void *opaque)
VirtIOSerial *s = opaque; VirtIOSerial *s = opaque;
VirtIOSerialPort *port; VirtIOSerialPort *port;
uint32_t nr_active_ports; uint32_t nr_active_ports;
unsigned int i; unsigned int i, max_nr_ports;
/* The virtio device */ /* The virtio device */
virtio_save(&s->vdev, f); virtio_save(&s->vdev, f);
@ -506,8 +506,8 @@ static void virtio_serial_save(QEMUFile *f, void *opaque)
qemu_put_be32s(f, &s->config.max_nr_ports); qemu_put_be32s(f, &s->config.max_nr_ports);
/* The ports map */ /* The ports map */
max_nr_ports = tswap32(s->config.max_nr_ports);
for (i = 0; i < (s->config.max_nr_ports + 31) / 32; i++) { for (i = 0; i < (max_nr_ports + 31) / 32; i++) {
qemu_put_be32s(f, &s->ports_map[i]); qemu_put_be32s(f, &s->ports_map[i]);
} }
@ -568,7 +568,8 @@ static int virtio_serial_load(QEMUFile *f, void *opaque, int version_id)
qemu_get_be16s(f, &s->config.rows); qemu_get_be16s(f, &s->config.rows);
qemu_get_be32s(f, &max_nr_ports); qemu_get_be32s(f, &max_nr_ports);
if (max_nr_ports > s->config.max_nr_ports) { tswap32s(&max_nr_ports);
if (max_nr_ports > tswap32(s->config.max_nr_ports)) {
/* Source could have had more ports than us. Fail migration. */ /* Source could have had more ports than us. Fail migration. */
return -EINVAL; return -EINVAL;
} }
@ -670,9 +671,10 @@ static void virtser_bus_dev_print(Monitor *mon, DeviceState *qdev, int indent)
/* This function is only used if a port id is not provided by the user */ /* This function is only used if a port id is not provided by the user */
static uint32_t find_free_port_id(VirtIOSerial *vser) static uint32_t find_free_port_id(VirtIOSerial *vser)
{ {
unsigned int i; unsigned int i, max_nr_ports;
for (i = 0; i < (vser->config.max_nr_ports + 31) / 32; i++) { max_nr_ports = tswap32(vser->config.max_nr_ports);
for (i = 0; i < (max_nr_ports + 31) / 32; i++) {
uint32_t map, bit; uint32_t map, bit;
map = vser->ports_map[i]; map = vser->ports_map[i];
@ -720,7 +722,7 @@ static int virtser_port_qdev_init(DeviceState *qdev, DeviceInfo *base)
VirtIOSerialPort *port = DO_UPCAST(VirtIOSerialPort, dev, qdev); VirtIOSerialPort *port = DO_UPCAST(VirtIOSerialPort, dev, qdev);
VirtIOSerialPortInfo *info = DO_UPCAST(VirtIOSerialPortInfo, qdev, base); VirtIOSerialPortInfo *info = DO_UPCAST(VirtIOSerialPortInfo, qdev, base);
VirtIOSerialBus *bus = DO_UPCAST(VirtIOSerialBus, qbus, qdev->parent_bus); VirtIOSerialBus *bus = DO_UPCAST(VirtIOSerialBus, qbus, qdev->parent_bus);
int ret; int ret, max_nr_ports;
bool plugging_port0; bool plugging_port0;
port->vser = bus->vser; port->vser = bus->vser;
@ -750,9 +752,10 @@ static int virtser_port_qdev_init(DeviceState *qdev, DeviceInfo *base)
} }
} }
if (port->id >= port->vser->config.max_nr_ports) { max_nr_ports = tswap32(port->vser->config.max_nr_ports);
if (port->id >= max_nr_ports) {
error_report("virtio-serial-bus: Out-of-range port id specified, max. allowed: %u\n", error_report("virtio-serial-bus: Out-of-range port id specified, max. allowed: %u\n",
port->vser->config.max_nr_ports - 1); max_nr_ports - 1);
return -1; return -1;
} }
@ -863,7 +866,7 @@ VirtIODevice *virtio_serial_init(DeviceState *dev, virtio_serial_conf *conf)
vser->ovqs[i] = virtio_add_queue(vdev, 128, handle_output); vser->ovqs[i] = virtio_add_queue(vdev, 128, handle_output);
} }
vser->config.max_nr_ports = conf->max_virtserial_ports; vser->config.max_nr_ports = tswap32(conf->max_virtserial_ports);
vser->ports_map = qemu_mallocz(((conf->max_virtserial_ports + 31) / 32) vser->ports_map = qemu_mallocz(((conf->max_virtserial_ports + 31) / 32)
* sizeof(vser->ports_map[0])); * sizeof(vser->ports_map[0]));
/* /*