From c29834584ea4eafccf2f62a0b8a32e64f792044c Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Tue, 25 Nov 2008 13:36:26 +0100 Subject: [PATCH] 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 Signed-off-by: Rusty Russell --- drivers/char/hvc_console.c | 1 + drivers/char/virtio_console.c | 30 +++++++++++++++++++++++++++++- include/linux/virtio_console.h | 11 +++++++++++ 3 files changed, 41 insertions(+), 1 deletion(-) diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c index fb57f67bb427..0587b66d6fc7 100644 --- a/drivers/char/hvc_console.c +++ b/drivers/char/hvc_console.c @@ -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 diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index 3fb0d2c88ba5..ff6f5a4b58fb 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -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) diff --git a/include/linux/virtio_console.h b/include/linux/virtio_console.h index 19a0da0dba41..7615ffcdd555 100644 --- a/include/linux/virtio_console.h +++ b/include/linux/virtio_console.h @@ -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__ */