Skip to content

Commit

Permalink
um: fully use tty_port
Browse files Browse the repository at this point in the history
... use all tty_port helpers

Signed-off-by: Richard Weinberger <richard@nod.at>
  • Loading branch information
Richard Weinberger committed Jul 28, 2012
1 parent df7b86f commit 79e0273
Show file tree
Hide file tree
Showing 4 changed files with 65 additions and 78 deletions.
102 changes: 45 additions & 57 deletions arch/um/drivers/line.c
Original file line number Diff line number Diff line change
Expand Up @@ -296,88 +296,75 @@ int line_setup_irq(int fd, int input, int output, struct line *line, void *data)
return err;
}

/*
* Normally, a driver like this can rely mostly on the tty layer
* locking, particularly when it comes to the driver structure.
* However, in this case, mconsole requests can come in "from the
* side", and race with opens and closes.
*
* mconsole config requests will want to be sure the device isn't in
* use, and get_config, open, and close will want a stable
* configuration. The checking and modification of the configuration
* is done under a spinlock. Checking whether the device is in use is
* line->tty->count > 1, also under the spinlock.
*
* line->count serves to decide whether the device should be enabled or
* disabled on the host. If it's equal to 0, then we are doing the
* first open or last close. Otherwise, open and close just return.
*/

int line_open(struct line *lines, struct tty_struct *tty)
static int line_activate(struct tty_port *port, struct tty_struct *tty)
{
struct line *line = &lines[tty->index];
int err = -ENODEV;

mutex_lock(&line->count_lock);
if (!line->valid)
goto out_unlock;

err = 0;
if (line->port.count++)
goto out_unlock;

BUG_ON(tty->driver_data);
tty->driver_data = line;
tty_port_tty_set(&line->port, tty);
int ret;
struct line *line = tty->driver_data;

err = enable_chan(line);
if (err) /* line_close() will be called by our caller */
goto out_unlock;
ret = enable_chan(line);
if (ret)
return ret;

if (!line->sigio) {
chan_enable_winch(line->chan_out, tty);
line->sigio = 1;
}

chan_window_size(line, &tty->winsize.ws_row,
&tty->winsize.ws_col);
out_unlock:
mutex_unlock(&line->count_lock);
return err;
&tty->winsize.ws_col);

return 0;
}

static void unregister_winch(struct tty_struct *tty);
static const struct tty_port_operations line_port_ops = {
.activate = line_activate,
};

void line_close(struct tty_struct *tty, struct file * filp)
int line_open(struct tty_struct *tty, struct file *filp)
{
struct line *line = tty->driver_data;

/*
* If line_open fails (and tty->driver_data is never set),
* tty_open will call line_close. So just return in this case.
*/
if (line == NULL)
return;
return tty_port_open(&line->port, tty, filp);
}

/* We ignore the error anyway! */
flush_buffer(line);
int line_install(struct tty_driver *driver, struct tty_struct *tty,
struct line *line)
{
int ret;

mutex_lock(&line->count_lock);
BUG_ON(!line->valid);
ret = tty_standard_install(driver, tty);
if (ret)
return ret;

tty->driver_data = line;

if (--line->port.count)
goto out_unlock;
return 0;
}

static void unregister_winch(struct tty_struct *tty);

tty_port_tty_set(&line->port, NULL);
tty->driver_data = NULL;
void line_cleanup(struct tty_struct *tty)
{
struct line *line = tty->driver_data;

if (line->sigio) {
unregister_winch(tty);
line->sigio = 0;
}
}

out_unlock:
mutex_unlock(&line->count_lock);
void line_close(struct tty_struct *tty, struct file * filp)
{
struct line *line = tty->driver_data;

tty_port_close(&line->port, tty, filp);
}

void line_hangup(struct tty_struct *tty)
{
struct line *line = tty->driver_data;

tty_port_hangup(&line->port);
}

void close_lines(struct line *lines, int nlines)
Expand Down Expand Up @@ -589,6 +576,7 @@ int register_lines(struct line_driver *line_driver,

for (i = 0; i < nlines; i++) {
tty_port_init(&lines[i].port);
lines[i].port.ops = &line_port_ops;
spin_lock_init(&lines[i].lock);
mutex_init(&lines[i].count_lock);
lines[i].driver = line_driver;
Expand Down
6 changes: 5 additions & 1 deletion arch/um/drivers/line.h
Original file line number Diff line number Diff line change
Expand Up @@ -58,7 +58,11 @@ struct line {
};

extern void line_close(struct tty_struct *tty, struct file * filp);
extern int line_open(struct line *lines, struct tty_struct *tty);
extern int line_open(struct tty_struct *tty, struct file *filp);
extern int line_install(struct tty_driver *driver, struct tty_struct *tty,
struct line *line);
extern void line_cleanup(struct tty_struct *tty);
extern void line_hangup(struct tty_struct *tty);
extern int line_setup(char **conf, unsigned nlines, char **def,
char *init, char *name);
extern int line_write(struct tty_struct *tty, const unsigned char *buf,
Expand Down
15 changes: 6 additions & 9 deletions arch/um/drivers/ssl.c
Original file line number Diff line number Diff line change
Expand Up @@ -87,19 +87,13 @@ static int ssl_remove(int n, char **error_out)
error_out);
}

static int ssl_open(struct tty_struct *tty, struct file *filp)
static int ssl_install(struct tty_driver *driver, struct tty_struct *tty)
{
int err = line_open(serial_lines, tty);

if (err)
printk(KERN_ERR "Failed to open serial line %d, err = %d\n",
tty->index, err);

return err;
return line_install(driver, tty, &serial_lines[tty->index]);
}

static const struct tty_operations ssl_ops = {
.open = ssl_open,
.open = line_open,
.close = line_close,
.write = line_write,
.put_char = line_put_char,
Expand All @@ -110,6 +104,9 @@ static const struct tty_operations ssl_ops = {
.set_termios = line_set_termios,
.throttle = line_throttle,
.unthrottle = line_unthrottle,
.install = ssl_install,
.cleanup = line_cleanup,
.hangup = line_hangup,
};

/* Changed by ssl_init and referenced by ssl_exit, which are both serialized
Expand Down
20 changes: 9 additions & 11 deletions arch/um/drivers/stdio_console.c
Original file line number Diff line number Diff line change
Expand Up @@ -89,21 +89,17 @@ static int con_remove(int n, char **error_out)
return line_remove(vts, ARRAY_SIZE(vts), n, error_out);
}

static int con_open(struct tty_struct *tty, struct file *filp)
{
int err = line_open(vts, tty);
if (err)
printk(KERN_ERR "Failed to open console %d, err = %d\n",
tty->index, err);

return err;
}

/* Set in an initcall, checked in an exitcall */
static int con_init_done = 0;

static int con_install(struct tty_driver *driver, struct tty_struct *tty)
{
return line_install(driver, tty, &vts[tty->index]);
}

static const struct tty_operations console_ops = {
.open = con_open,
.open = line_open,
.install = con_install,
.close = line_close,
.write = line_write,
.put_char = line_put_char,
Expand All @@ -114,6 +110,8 @@ static const struct tty_operations console_ops = {
.set_termios = line_set_termios,
.throttle = line_throttle,
.unthrottle = line_unthrottle,
.cleanup = line_cleanup,
.hangup = line_hangup,
};

static void uml_console_write(struct console *console, const char *string,
Expand Down

0 comments on commit 79e0273

Please sign in to comment.