diff options
| -rw-r--r-- | drivers/tty/hvc/hvc_xen.c | 3 | ||||
| -rw-r--r-- | include/xen/interface/io/console.h | 13 |
2 files changed, 16 insertions, 0 deletions
diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c index 7f0b6262488c..c407592442cd 100644 --- a/drivers/tty/hvc/hvc_xen.c +++ b/drivers/tty/hvc/hvc_xen.c @@ -139,6 +139,9 @@ static ssize_t domU_write_console(uint32_t vtermno, const u8 *data, size_t len) if (cons == NULL) return -EINVAL; + if (cons->intf->connection == XENCONSOLE_DISCONNECTED) + return -ENOTCONN; + /* * Make sure the whole buffer is emitted, polling if * necessary. We don't ever want to rely on the hvc daemon diff --git a/include/xen/interface/io/console.h b/include/xen/interface/io/console.h index cf17e89ed861..687949bdebb1 100644 --- a/include/xen/interface/io/console.h +++ b/include/xen/interface/io/console.h @@ -19,6 +19,19 @@ struct xencons_interface { char out[2048]; XENCONS_RING_IDX in_cons, in_prod; XENCONS_RING_IDX out_cons, out_prod; +/* + * Flag values signaling from backend to frontend whether the console is + * connected. i.e. Whether it will be serviced and emptied. + * + * The flag starts as disconnected. + */ +#define XENCONSOLE_DISCONNECTED 1 +/* + * The flag is set to connected when the backend connects and the console + * will be serviced. + */ +#define XENCONSOLE_CONNECTED 0 + uint8_t connection; }; #endif /* __XEN_PUBLIC_IO_CONSOLE_H__ */ |