virtio_console: support console resizing

this patch uses the new hvc callback hvc_resize to set the window size
which allows to change the tty size of hvc_console via a hvc_resize
function.

I have added a new feature bit VIRTIO_CONSOLE_F_SIZE. The driver will
change the window size on tty open and via the config_changed callback
of the transport. Currently lguest and kvm_s390 have not implemented this
callback, but the callback can be implemented at a later point in time.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Christian Borntraeger 2008-11-25 13:36:26 +01:00 committed by Rusty Russell
parent 29f9f12ec7
commit c29834584e
3 changed files with 41 additions and 1 deletions

View File

@ -695,6 +695,7 @@ void hvc_resize(struct hvc_struct *hp, struct winsize ws)
hp->ws = ws;
schedule_work(&hp->tty_resize);
}
EXPORT_SYMBOL_GPL(hvc_resize);
/*
* This kthread is either polling or interrupt driven. This is determined by

View File

@ -137,13 +137,34 @@ int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int))
return hvc_instantiate(0, 0, &virtio_cons);
}
/*
* virtio console configuration. This supports:
* - console resize
*/
static void virtcons_apply_config(struct virtio_device *dev)
{
struct winsize ws;
if (virtio_has_feature(dev, VIRTIO_CONSOLE_F_SIZE)) {
dev->config->get(dev,
offsetof(struct virtio_console_config, cols),
&ws.ws_col, sizeof(u16));
dev->config->get(dev,
offsetof(struct virtio_console_config, rows),
&ws.ws_row, sizeof(u16));
hvc_resize(hvc, ws);
}
}
/*
* we support only one console, the hvc struct is a global var
* There is no need to do anything
* We set the configuration at this point, since we now have a tty
*/
static int notifier_add_vio(struct hvc_struct *hp, int data)
{
hp->irq_requested = 1;
virtcons_apply_config(vdev);
return 0;
}
@ -234,11 +255,18 @@ static struct virtio_device_id id_table[] = {
{ 0 },
};
static unsigned int features[] = {
VIRTIO_CONSOLE_F_SIZE,
};
static struct virtio_driver virtio_console = {
.feature_table = features,
.feature_table_size = ARRAY_SIZE(features),
.driver.name = KBUILD_MODNAME,
.driver.owner = THIS_MODULE,
.id_table = id_table,
.probe = virtcons_probe,
.config_changed = virtcons_apply_config,
};
static int __init init(void)

View File

@ -7,6 +7,17 @@
/* The ID for virtio console */
#define VIRTIO_ID_CONSOLE 3
/* Feature bits */
#define VIRTIO_CONSOLE_F_SIZE 0 /* Does host provide console size? */
struct virtio_console_config {
/* colums of the screens */
__u16 cols;
/* rows of the screens */
__u16 rows;
} __attribute__((packed));
#ifdef __KERNEL__
int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int));
#endif /* __KERNEL__ */