diff options
Diffstat (limited to 'drivers/tty/n_tty.c')
-rw-r--r-- | drivers/tty/n_tty.c | 87 |
1 files changed, 39 insertions, 48 deletions
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c index 268b62768f2..fdc2ecde5ac 100644 --- a/drivers/tty/n_tty.c +++ b/drivers/tty/n_tty.c @@ -274,7 +274,8 @@ static void n_tty_check_unthrottle(struct tty_struct *tty) return; n_tty_set_room(tty); n_tty_write_wakeup(tty->link); - wake_up_interruptible_poll(&tty->link->write_wait, POLLOUT); + if (waitqueue_active(&tty->link->write_wait)) + wake_up_interruptible_poll(&tty->link->write_wait, POLLOUT); return; } @@ -349,7 +350,8 @@ static void n_tty_packet_mode_flush(struct tty_struct *tty) spin_lock_irqsave(&tty->ctrl_lock, flags); if (tty->link->packet) { tty->ctrl_status |= TIOCPKT_FLUSHREAD; - wake_up_interruptible(&tty->link->read_wait); + if (waitqueue_active(&tty->link->read_wait)) + wake_up_interruptible(&tty->link->read_wait); } spin_unlock_irqrestore(&tty->ctrl_lock, flags); } @@ -1157,7 +1159,8 @@ static void n_tty_receive_break(struct tty_struct *tty) put_tty_queue('\0', ldata); } put_tty_queue('\0', ldata); - wake_up_interruptible(&tty->read_wait); + if (waitqueue_active(&tty->read_wait)) + wake_up_interruptible(&tty->read_wait); } /** @@ -1215,7 +1218,8 @@ static void n_tty_receive_parity_error(struct tty_struct *tty, unsigned char c) put_tty_queue('\0', ldata); else put_tty_queue(c, ldata); - wake_up_interruptible(&tty->read_wait); + if (waitqueue_active(&tty->read_wait)) + wake_up_interruptible(&tty->read_wait); } static void @@ -1259,7 +1263,6 @@ static int n_tty_receive_char_special(struct tty_struct *tty, unsigned char c) { struct n_tty_data *ldata = tty->disc_data; - int parmrk; if (I_IXON(tty)) { if (c == START_CHAR(tty)) { @@ -1344,8 +1347,6 @@ n_tty_receive_char_special(struct tty_struct *tty, unsigned char c) } if ((c == EOL_CHAR(tty)) || (c == EOL2_CHAR(tty) && L_IEXTEN(tty))) { - parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) - ? 1 : 0; /* * XXX are EOL_CHAR and EOL2_CHAR echoed?!? */ @@ -1360,7 +1361,7 @@ n_tty_receive_char_special(struct tty_struct *tty, unsigned char c) * XXX does PARMRK doubling happen for * EOL_CHAR and EOL2_CHAR? */ - if (parmrk) + if (c == (unsigned char) '\377' && I_PARMRK(tty)) put_tty_queue(c, ldata); handle_newline: @@ -1374,7 +1375,6 @@ handle_newline: } } - parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0; if (L_ECHO(tty)) { finish_erasing(ldata); if (c == '\n') @@ -1388,7 +1388,8 @@ handle_newline: commit_echoes(tty); } - if (parmrk) + /* PARMRK doubling check */ + if (c == (unsigned char) '\377' && I_PARMRK(tty)) put_tty_queue(c, ldata); put_tty_queue(c, ldata); @@ -1399,7 +1400,6 @@ static inline void n_tty_receive_char_inline(struct tty_struct *tty, unsigned char c) { struct n_tty_data *ldata = tty->disc_data; - int parmrk; if (tty->stopped && !tty->flow_stopped && I_IXON(tty) && I_IXANY(tty)) { start_tty(tty); @@ -1413,13 +1413,13 @@ n_tty_receive_char_inline(struct tty_struct *tty, unsigned char c) echo_char(c, tty); commit_echoes(tty); } - parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0; - if (parmrk) + /* PARMRK doubling check */ + if (c == (unsigned char) '\377' && I_PARMRK(tty)) put_tty_queue(c, ldata); put_tty_queue(c, ldata); } -static inline void n_tty_receive_char(struct tty_struct *tty, unsigned char c) +static void n_tty_receive_char(struct tty_struct *tty, unsigned char c) { n_tty_receive_char_inline(tty, c); } @@ -1444,8 +1444,7 @@ n_tty_receive_char_fast(struct tty_struct *tty, unsigned char c) put_tty_queue(c, ldata); } -static inline void -n_tty_receive_char_closing(struct tty_struct *tty, unsigned char c) +static void n_tty_receive_char_closing(struct tty_struct *tty, unsigned char c) { if (I_ISTRIP(tty)) c &= 0x7f; @@ -1676,32 +1675,9 @@ static void __receive_buf(struct tty_struct *tty, const unsigned char *cp, } } -static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp, - char *fp, int count) -{ - int room, n; - - down_read(&tty->termios_rwsem); - - while (1) { - room = receive_room(tty); - n = min(count, room); - if (!n) - break; - __receive_buf(tty, cp, fp, n); - cp += n; - if (fp) - fp += n; - count -= n; - } - - tty->receive_room = room; - n_tty_check_throttle(tty); - up_read(&tty->termios_rwsem); -} - -static int n_tty_receive_buf2(struct tty_struct *tty, const unsigned char *cp, - char *fp, int count) +static int +n_tty_receive_buf_common(struct tty_struct *tty, const unsigned char *cp, + char *fp, int count, int flow) { struct n_tty_data *ldata = tty->disc_data; int room, n, rcvd = 0; @@ -1712,7 +1688,7 @@ static int n_tty_receive_buf2(struct tty_struct *tty, const unsigned char *cp, room = receive_room(tty); n = min(count, room); if (!n) { - if (!room) + if (flow && !room) ldata->no_room = 1; break; } @@ -1731,6 +1707,18 @@ static int n_tty_receive_buf2(struct tty_struct *tty, const unsigned char *cp, return rcvd; } +static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp, + char *fp, int count) +{ + n_tty_receive_buf_common(tty, cp, fp, count, 0); +} + +static int n_tty_receive_buf2(struct tty_struct *tty, const unsigned char *cp, + char *fp, int count) +{ + return n_tty_receive_buf_common(tty, cp, fp, count, 1); +} + int is_ignored(int sig) { return (sigismember(¤t->blocked, sig) || @@ -1820,8 +1808,10 @@ static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old) start_tty(tty); /* The termios change make the tty ready for I/O */ - wake_up_interruptible(&tty->write_wait); - wake_up_interruptible(&tty->read_wait); + if (waitqueue_active(&tty->write_wait)) + wake_up_interruptible(&tty->write_wait); + if (waitqueue_active(&tty->read_wait)) + wake_up_interruptible(&tty->read_wait); } /** @@ -1887,14 +1877,15 @@ err: return -ENOMEM; } -static inline int input_available_p(struct tty_struct *tty, int amt) +static inline int input_available_p(struct tty_struct *tty, int poll) { struct n_tty_data *ldata = tty->disc_data; + int amt = poll && !TIME_CHAR(tty) ? MIN_CHAR(tty) : 1; if (ldata->icanon && !L_EXTPROC(tty)) { if (ldata->canon_head != ldata->read_tail) return 1; - } else if (read_cnt(ldata) >= (amt ? amt : 1)) + } else if (read_cnt(ldata) >= amt) return 1; return 0; @@ -2393,7 +2384,7 @@ static unsigned int n_tty_poll(struct tty_struct *tty, struct file *file, poll_wait(file, &tty->read_wait, wait); poll_wait(file, &tty->write_wait, wait); - if (input_available_p(tty, TIME_CHAR(tty) ? 0 : MIN_CHAR(tty))) + if (input_available_p(tty, 1)) mask |= POLLIN | POLLRDNORM; if (tty->packet && tty->link->ctrl_status) mask |= POLLPRI | POLLIN | POLLRDNORM; |