as it ignores the '#' and tries to access them anyway.
Every Xenolinux instance owns a bidirectional 'virtual
-console'. Boot-time output can be directed to this console by
-specifying 'console=xencons0' as a boot parameter. It is also possible
-to log in via the virtual console. To do this, you must run a mingetty
-on the virtual console, which you can achieve as follows:
+console'. Boot-time output will be directed to this console by default
+for all domain other than 0 (because the console name is tty0); domain
+0 requires you to specify 'console=xencons0' as a boot parameter. It
+is also possible to log in via the virtual console --- once again, for
+most domains your normal startup scripts will work as normal (e.g., by
+running mingetty on tty1-7). For domain 0, you must connect to the
+special 'xencons' device node:
# mkdir -p /dev/xen
# mknod /dev/xen/cons c 4 123
# echo "c:2345:respawn:/sbin/mingetty --noclear xen/cons" >>/etc/inittab
-If you wish to permit root logins via the virtual console then you must
-also add 'xen/cons' to the list of trusted ttys in /etc/securetty.
+If you wish to permit root logins via the special DOM0 node then you
+must also add 'xen/cons' to the list of trusted ttys in
+/etc/securetty.
Note that, because domains>0 don't have any privileged access at all,
certain commands in the default boot sequence will fail e.g. attempts
Logging in via virtual console
------------------------------
It is possible to log in to a guest OS via its virtual console if a
- 'getty' is running. To achieve this, a suitable device node must be
- created, and a new line added to inittab:
+ 'getty' is running. In most domains the virtual console is named tty1
+ so standard startup scripts and /etc/inittab should work
+ fine. Furthermore, tty2-63 are created as dummy console devices to
+ suppress warnings from standard startup scripts.
+
+ In domain 0 we avoid conflict with the 'real' console by registering
+ the virtual console with a special device number. A suitable device
+ node must therefore be created, and a new line added to inittab:
# mkdir -p /dev/xen
# mknod /dev/xen/cons c 4 123
# echo "c:2345:respawn:/sbin/mingetty --noclear xen/cons" >>/etc/inittab
-
- [NOTE to users in the lab -- existing Xen installations may be running
- mingetty on /dev/console. This is incorrect behaviour! Please modify
- such setups to run mingetty on /dev/xen/cons.]
-
Additionally, if you wish to allow root logins via the virtual
console, then 'xen/cons' must be added to the trusted tty list in
/etc/securetty. On some systems you *may* also need to modify the
Virtual console for other domains
---------------------------------
Every guest OS has a virtual console that is accessible via
- 'console=xencons0' at boot time, or mingetty running on
- /dev/xen/cons. However, domains other than domain 0 do not have access
- to the physical serial line. Instead, their console data is sent to
- and from a control daemon running in domain 0. When properly
- installed, this daemon can be started from the init scripts (e.g.,
- rc.local):
+ 'console=tty0' at boot time (or 'console=xencons0' for domain 0), and
+ mingetty running on /dev/tty1 (or /dev/xen/cons for domain 0).
+ However, domains other than domain 0 do not have access to the
+ physical serial line. Instead, their console data is sent to and from
+ a control daemon running in domain 0. When properly installed, this
+ daemon can be started from the init scripts (e.g., rc.local):
# /usr/sbin/xend start
Alternatively, Redhat- and LSB-compatible Linux installations can use
from a copy in tools/misc/xencons. An alternative to manually running
a terminal client is to specify '-c' to xc_dom_create.py, or add
'auto_console=True' to the defaults file. This will cause
-xc_dom_create.py to automatically become teh console terminal after
+xc_dom_create.py to automatically become the console terminal after
starting the domain.
-Boot-time output can be directed to this 'virtual console' by
-specifying 'console=xencons0' as a boot parameter. It is also possible
-to log in via the virtual console. To do this, you must run a mingetty
-on the virtual console, which you can achieve as follows:
- # mkdir -p /dev/xen
- # mknod /dev/xen/cons c 4 123
- # echo "c:2345:respawn:/sbin/mingetty --noclear xen/cons" >>/etc/inittab
-If you wish to permit root logins via the virtual console then you must
-also add 'xen/cons' to the list of trusted ttys in /etc/securetty.
+Boot-time output will be directed to this console by default, because
+the console name is tty0. It is also possible to log in via the
+virtual console --- once again, your normal startup scripts will work
+as normal (e.g., by running mingetty on tty1-7).
Manage Running Domains
#include <asm/hypervisor-ifs/event_channel.h>
#include <asm/ctrl_if.h>
-#define XEN_TTY_MINOR 123
+/*
+ * NB. /dev/xencons[0-9]+ are only exported by domain 0.
+ * All other domains use the normal /dev/tty[0-9]+ device nodes.
+ * Only /dev/tty1 is currently hooked up to real I/O -- all others are
+ * dummies to suppress warnings from standard distro startip scripts.
+ */
+#define XENCONS_TTY_MINOR 123
/* The kernel and user-land drivers share a common transmit buffer. */
#define WBUF_SIZE 4096
static kdev_t kcons_device(struct console *c)
{
- /*
- * This is the magic that binds our "struct console" to our
- * "tty_struct", defined below.
- */
- return MKDEV(TTY_MAJOR, XEN_TTY_MINOR);
+ return MKDEV(TTY_MAJOR, 1);
+}
+
+static kdev_t kcons_device_dom0(struct console *c)
+{
+ return MKDEV(TTY_MAJOR, XENCONS_TTY_MINOR);
}
static struct console kcons_info = {
- name: "xencons",
- device: kcons_device,
flags: CON_PRINTBUFFER,
index: -1,
};
void xen_console_init(void)
{
+ if ( start_info.flags & SIF_INITDOMAIN )
+ {
+ strcpy(kcons_info.name, "xencons");
+ kcons_info.device = kcons_device_dom0;
+ kcons_info.write = kcons_write_dom0;
+ }
+ else
+ {
+ strcpy(kcons_info.name, "tty");
+ kcons_info.device = kcons_device;
+ kcons_info.write = kcons_write;
+ }
+
kcons_info.write =
(start_info.flags & SIF_INITDOMAIN) ? kcons_write_dom0 : kcons_write;
register_console(&kcons_info);
static struct tty_driver xencons_driver;
static int xencons_refcount;
-static struct tty_struct *xencons_table[1];
-static struct termios *xencons_termios[1];
-static struct termios *xencons_termios_locked[1];
+static struct tty_struct *xencons_table[MAX_NR_CONSOLES];
+static struct termios *xencons_termios[MAX_NR_CONSOLES];
+static struct termios *xencons_termios_locked[MAX_NR_CONSOLES];
static struct tty_struct *xencons_tty;
static int xencons_priv_irq;
static char x_char;
static void xencons_send_xchar(struct tty_struct *tty, char ch)
{
unsigned long flags;
+
+ if ( MINOR(tty->device) != xencons_driver.minor_start )
+ return;
+
spin_lock_irqsave(&xencons_lock, flags);
x_char = ch;
__xencons_tx_flush();
static void xencons_throttle(struct tty_struct *tty)
{
+ if ( MINOR(tty->device) != xencons_driver.minor_start )
+ return;
+
if ( I_IXOFF(tty) )
xencons_send_xchar(tty, STOP_CHAR(tty));
}
static void xencons_unthrottle(struct tty_struct *tty)
{
+ if ( MINOR(tty->device) != xencons_driver.minor_start )
+ return;
+
if ( I_IXOFF(tty) )
{
if ( x_char != 0 )
static void xencons_flush_buffer(struct tty_struct *tty)
{
unsigned long flags;
+
+ if ( MINOR(tty->device) != xencons_driver.minor_start )
+ return;
+
spin_lock_irqsave(&xencons_lock, flags);
wc = wp = 0;
spin_unlock_irqrestore(&xencons_lock, flags);
if ( from_user && verify_area(VERIFY_READ, buf, count) )
return -EINVAL;
+ if ( MINOR(tty->device) != xencons_driver.minor_start )
+ return count;
+
spin_lock_irqsave(&xencons_lock, flags);
for ( i = 0; i < count; i++ )
static void xencons_put_char(struct tty_struct *tty, u_char ch)
{
unsigned long flags;
+
+ if ( MINOR(tty->device) != xencons_driver.minor_start )
+ return;
+
spin_lock_irqsave(&xencons_lock, flags);
(void)__xencons_put_char(ch);
spin_unlock_irqrestore(&xencons_lock, flags);
static void xencons_flush_chars(struct tty_struct *tty)
{
unsigned long flags;
+
+ if ( MINOR(tty->device) != xencons_driver.minor_start )
+ return;
+
spin_lock_irqsave(&xencons_lock, flags);
__xencons_tx_flush();
spin_unlock_irqrestore(&xencons_lock, flags);
{
unsigned long orig_jiffies = jiffies;
+ if ( MINOR(tty->device) != xencons_driver.minor_start )
+ return;
+
while ( tty->driver.chars_in_buffer(tty) )
{
set_current_state(TASK_INTERRUPTIBLE);
int line;
unsigned long flags;
+ if ( MINOR(tty->device) != xencons_driver.minor_start )
+ return 0;
+
MOD_INC_USE_COUNT;
line = MINOR(tty->device) - tty->driver.minor_start;
if ( line != 0 )
{
unsigned long flags;
+ if ( MINOR(tty->device) != xencons_driver.minor_start )
+ return;
+
if ( tty->count == 1 )
{
tty->closing = 1;
{
memset(&xencons_driver, 0, sizeof(struct tty_driver));
xencons_driver.magic = TTY_DRIVER_MAGIC;
- xencons_driver.name = "xencons";
xencons_driver.major = TTY_MAJOR;
- xencons_driver.minor_start = XEN_TTY_MINOR;
- xencons_driver.num = 1;
+ xencons_driver.num = MAX_NR_CONSOLES;
xencons_driver.type = TTY_DRIVER_TYPE_SERIAL;
xencons_driver.subtype = SERIAL_TYPE_NORMAL;
xencons_driver.init_termios = tty_std_termios;
xencons_driver.termios = xencons_termios;
xencons_driver.termios_locked = xencons_termios_locked;
+ if ( start_info.flags & SIF_INITDOMAIN )
+ {
+ xencons_driver.name = "xencons";
+ xencons_driver.minor_start = XENCONS_TTY_MINOR;
+ }
+ else
+ {
+ xencons_driver.name = "tty";
+ xencons_driver.minor_start = 1;
+ }
+
xencons_driver.open = xencons_open;
xencons_driver.close = xencons_close;
xencons_driver.write = xencons_write;
projects / xen.git / commitdiff