um: Use tty_port in SIGWINCH handler

The tty below tty_port might get destroyed by the tty layer
while we hold a reference to it.
So we have to carry tty_port around...

Signed-off-by: Richard Weinberger <richard@nod.at>
This commit is contained in:
Richard Weinberger 2013-03-11 10:05:45 +01:00
parent cc4f02486c
commit 2116bda6ad
5 changed files with 22 additions and 18 deletions

View File

@ -37,7 +37,7 @@ extern int console_write_chan(struct chan *chan, const char *buf,
extern int console_open_chan(struct line *line, struct console *co);
extern void deactivate_chan(struct chan *chan, int irq);
extern void reactivate_chan(struct chan *chan, int irq);
extern void chan_enable_winch(struct chan *chan, struct tty_struct *tty);
extern void chan_enable_winch(struct chan *chan, struct tty_port *port);
extern int enable_chan(struct line *line);
extern void close_chan(struct line *line);
extern int chan_window_size(struct line *line,

View File

@ -122,10 +122,10 @@ static int open_chan(struct list_head *chans)
return err;
}
void chan_enable_winch(struct chan *chan, struct tty_struct *tty)
void chan_enable_winch(struct chan *chan, struct tty_port *port)
{
if (chan && chan->primary && chan->ops->winch)
register_winch(chan->fd, tty);
register_winch(chan->fd, port);
}
static void line_timer_cb(struct work_struct *work)

View File

@ -216,7 +216,7 @@ static int winch_thread(void *arg)
}
}
static int winch_tramp(int fd, struct tty_struct *tty, int *fd_out,
static int winch_tramp(int fd, struct tty_port *port, int *fd_out,
unsigned long *stack_out)
{
struct winch_data data;
@ -271,7 +271,7 @@ static int winch_tramp(int fd, struct tty_struct *tty, int *fd_out,
return err;
}
void register_winch(int fd, struct tty_struct *tty)
void register_winch(int fd, struct tty_port *port)
{
unsigned long stack;
int pid, thread, count, thread_fd = -1;
@ -281,17 +281,17 @@ void register_winch(int fd, struct tty_struct *tty)
return;
pid = tcgetpgrp(fd);
if (is_skas_winch(pid, fd, tty)) {
register_winch_irq(-1, fd, -1, tty, 0);
if (is_skas_winch(pid, fd, port)) {
register_winch_irq(-1, fd, -1, port, 0);
return;
}
if (pid == -1) {
thread = winch_tramp(fd, tty, &thread_fd, &stack);
thread = winch_tramp(fd, port, &thread_fd, &stack);
if (thread < 0)
return;
register_winch_irq(thread_fd, fd, thread, tty, stack);
register_winch_irq(thread_fd, fd, thread, port, stack);
count = write(thread_fd, &c, sizeof(c));
if (count != sizeof(c))

View File

@ -38,10 +38,10 @@ extern int generic_window_size(int fd, void *unused, unsigned short *rows_out,
unsigned short *cols_out);
extern void generic_free(void *data);
struct tty_struct;
extern void register_winch(int fd, struct tty_struct *tty);
struct tty_port;
extern void register_winch(int fd, struct tty_port *port);
extern void register_winch_irq(int fd, int tty_fd, int pid,
struct tty_struct *tty, unsigned long stack);
struct tty_port *port, unsigned long stack);
#define __channel_help(fn, prefix) \
__uml_help(fn, prefix "[0-9]*=<channel description>\n" \

View File

@ -305,7 +305,7 @@ static int line_activate(struct tty_port *port, struct tty_struct *tty)
return ret;
if (!line->sigio) {
chan_enable_winch(line->chan_out, tty);
chan_enable_winch(line->chan_out, port);
line->sigio = 1;
}
@ -603,7 +603,7 @@ struct winch {
int fd;
int tty_fd;
int pid;
struct tty_struct *tty;
struct tty_port *port;
unsigned long stack;
struct work_struct work;
};
@ -657,7 +657,7 @@ static irqreturn_t winch_interrupt(int irq, void *data)
goto out;
}
}
tty = winch->tty;
tty = tty_port_tty_get(winch->port);
if (tty != NULL) {
line = tty->driver_data;
if (line != NULL) {
@ -665,6 +665,7 @@ static irqreturn_t winch_interrupt(int irq, void *data)
&tty->winsize.ws_col);
kill_pgrp(tty->pgrp, SIGWINCH, 1);
}
tty_kref_put(tty);
}
out:
if (winch->fd != -1)
@ -672,7 +673,7 @@ static irqreturn_t winch_interrupt(int irq, void *data)
return IRQ_HANDLED;
}
void register_winch_irq(int fd, int tty_fd, int pid, struct tty_struct *tty,
void register_winch_irq(int fd, int tty_fd, int pid, struct tty_port *port,
unsigned long stack)
{
struct winch *winch;
@ -687,7 +688,7 @@ void register_winch_irq(int fd, int tty_fd, int pid, struct tty_struct *tty,
.fd = fd,
.tty_fd = tty_fd,
.pid = pid,
.tty = tty,
.port = port,
.stack = stack });
if (um_request_irq(WINCH_IRQ, fd, IRQ_READ, winch_interrupt,
@ -716,15 +717,18 @@ static void unregister_winch(struct tty_struct *tty)
{
struct list_head *ele, *next;
struct winch *winch;
struct tty_struct *wtty;
spin_lock(&winch_handler_lock);
list_for_each_safe(ele, next, &winch_handlers) {
winch = list_entry(ele, struct winch, list);
if (winch->tty == tty) {
wtty = tty_port_tty_get(winch->port);
if (wtty == tty) {
free_winch(winch);
break;
}
tty_kref_put(wtty);
}
spin_unlock(&winch_handler_lock);
}