tty/serial: lay the foundations for the next set of reworks
- Stop drivers calling their own flush method indirectly, it obfuscates code
and it will change soon anyway
- A few more lock_kernel paths temporarily needed in some driver internal
waiting code
- Remove private put_char method that does a write call for one char - we
have that anyway
- Most but not yet all of the termios copy under lock fixing (some has other
dependencies to follow)
- Note a few locking bugs in drivers found in the process
- Kill remaining [ab]users of TIOCG/SSOFTCAR in the driver, these must go to
fix the termios locking
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/serial/68328serial.c b/drivers/serial/68328serial.c
index 2b8a410..5ce3e57 100644
--- a/drivers/serial/68328serial.c
+++ b/drivers/serial/68328serial.c
@@ -1017,18 +1017,6 @@
tty_wait_until_sent(tty, 0);
send_break(info, arg ? arg*(100) : 250);
return 0;
- case TIOCGSOFTCAR:
- error = put_user(C_CLOCAL(tty) ? 1 : 0,
- (unsigned long *) arg);
- if (error)
- return error;
- return 0;
- case TIOCSSOFTCAR:
- get_user(arg, (unsigned long *) arg);
- tty->termios->c_cflag =
- ((tty->termios->c_cflag & ~CLOCAL) |
- (arg ? CLOCAL : 0));
- return 0;
case TIOCGSERIAL:
if (access_ok(VERIFY_WRITE, (void *) arg,
sizeof(struct serial_struct)))
@@ -1061,9 +1049,6 @@
{
struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
- if (tty->termios->c_cflag == old_termios->c_cflag)
- return;
-
change_speed(info);
if ((old_termios->c_cflag & CRTSCTS) &&
@@ -1140,8 +1125,7 @@
uart->ustcnt &= ~(USTCNT_RXEN | USTCNT_RX_INTR_MASK);
shutdown(info);
- if (tty->driver->flush_buffer)
- tty->driver->flush_buffer(tty);
+ rs_flush_buffer(tty);
tty_ldisc_flush(tty);
tty->closing = 0;
diff --git a/drivers/serial/68360serial.c b/drivers/serial/68360serial.c
index 6f54010..f4f737b 100644
--- a/drivers/serial/68360serial.c
+++ b/drivers/serial/68360serial.c
@@ -1436,18 +1436,6 @@
return retval;
end_break(info);
return 0;
- case TIOCGSOFTCAR:
- /* return put_user(C_CLOCAL(tty) ? 1 : 0, (int *) arg); */
- put_user(C_CLOCAL(tty) ? 1 : 0, (int *) arg);
- return 0;
- case TIOCSSOFTCAR:
- error = get_user(arg, (unsigned int *) arg);
- if (error)
- return error;
- tty->termios->c_cflag =
- ((tty->termios->c_cflag & ~CLOCAL) |
- (arg ? CLOCAL : 0));
- return 0;
#ifdef maybe
case TIOCSERGETLSR: /* Get line status register */
return get_lsr_info(info, (unsigned int *) arg);
@@ -1665,8 +1653,7 @@
rs_360_wait_until_sent(tty, info->timeout);
}
shutdown(info);
- if (tty->driver->flush_buffer)
- tty->driver->flush_buffer(tty);
+ rs_360_flush_buffer(tty);
tty_ldisc_flush(tty);
tty->closing = 0;
info->event = 0;
@@ -1717,6 +1704,7 @@
printk("jiff=%lu...", jiffies);
#endif
+ lock_kernel();
/* We go through the loop at least once because we can't tell
* exactly when the last character exits the shifter. There can
* be at least two characters waiting to be sent after the buffers
@@ -1745,6 +1733,7 @@
bdp--;
} while (bdp->status & BD_SC_READY);
current->state = TASK_RUNNING;
+ unlock_kernel();
#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies);
#endif
diff --git a/drivers/serial/crisv10.c b/drivers/serial/crisv10.c
index 88e7c1d..8b9af73 100644
--- a/drivers/serial/crisv10.c
+++ b/drivers/serial/crisv10.c
@@ -3581,8 +3581,9 @@
unsigned int set, unsigned int clear)
{
struct e100_serial *info = (struct e100_serial *)tty->driver_data;
+ unsigned long flags;
- lock_kernel();
+ local_irq_save(flags);
if (clear & TIOCM_RTS)
e100_rts(info, 0);
@@ -3604,7 +3605,7 @@
if (set & TIOCM_CD)
e100_cd_out(info, 1);
- unlock_kernel();
+ local_irq_restore(flags);
return 0;
}
@@ -3613,8 +3614,10 @@
{
struct e100_serial *info = (struct e100_serial *)tty->driver_data;
unsigned int result;
+ unsigned long flags;
- lock_kernel();
+ local_irq_save(flags);
+
result =
(!E100_RTS_GET(info) ? TIOCM_RTS : 0)
| (!E100_DTR_GET(info) ? TIOCM_DTR : 0)
@@ -3623,7 +3626,7 @@
| (!E100_CD_GET(info) ? TIOCM_CAR : 0)
| (!E100_CTS_GET(info) ? TIOCM_CTS : 0);
- unlock_kernel();
+ local_irq_restore(flags);
#ifdef SERIAL_DEBUG_IO
printk(KERN_DEBUG "ser%i: modem state: %i 0x%08X\n",
@@ -3702,10 +3705,6 @@
{
struct e100_serial *info = (struct e100_serial *)tty->driver_data;
- if (tty->termios->c_cflag == old_termios->c_cflag &&
- tty->termios->c_iflag == old_termios->c_iflag)
- return;
-
change_speed(info);
/* Handle turning off CRTSCTS */
@@ -3808,10 +3807,8 @@
#endif
shutdown(info);
- if (tty->driver->flush_buffer)
- tty->driver->flush_buffer(tty);
- if (tty->ldisc.flush_buffer)
- tty->ldisc.flush_buffer(tty);
+ rs_flush_buffer(tty);
+ tty_ldisc_flush_buffer(tty);
tty->closing = 0;
info->event = 0;
info->tty = 0;
@@ -3885,6 +3882,7 @@
* Check R_DMA_CHx_STATUS bit 0-6=number of available bytes in FIFO
* R_DMA_CHx_HWSW bit 31-16=nbr of bytes left in DMA buffer (0=64k)
*/
+ lock_kernel();
orig_jiffies = jiffies;
while (info->xmit.head != info->xmit.tail || /* More in send queue */
(*info->ostatusadr & 0x007f) || /* more in FIFO */
@@ -3901,6 +3899,7 @@
curr_time_usec - info->last_tx_active_usec;
}
set_current_state(TASK_RUNNING);
+ unlock_kernel();
}
/*
diff --git a/drivers/serial/mcfserial.c b/drivers/serial/mcfserial.c
index ddd3aa5..aafa170 100644
--- a/drivers/serial/mcfserial.c
+++ b/drivers/serial/mcfserial.c
@@ -1072,18 +1072,6 @@
tty_wait_until_sent(tty, 0);
send_break(info, arg ? arg*(HZ/10) : HZ/4);
return 0;
- case TIOCGSOFTCAR:
- error = put_user(C_CLOCAL(tty) ? 1 : 0,
- (unsigned long *) arg);
- if (error)
- return error;
- return 0;
- case TIOCSSOFTCAR:
- get_user(arg, (unsigned long *) arg);
- tty->termios->c_cflag =
- ((tty->termios->c_cflag & ~CLOCAL) |
- (arg ? CLOCAL : 0));
- return 0;
case TIOCGSERIAL:
if (access_ok(VERIFY_WRITE, (void *) arg,
sizeof(struct serial_struct)))
@@ -1222,8 +1210,7 @@
} else
#endif
shutdown(info);
- if (tty->driver->flush_buffer)
- tty->driver->flush_buffer(tty);
+ mcfrs_flush_buffer(tty);
tty_ldisc_flush(tty);
tty->closing = 0;
@@ -1276,6 +1263,8 @@
* Note: we have to use pretty tight timings here to satisfy
* the NIST-PCTS.
*/
+ lock_kernel();
+
fifo_time = (MCF5272_FIFO_SIZE * HZ * 10) / info->baud;
char_time = fifo_time / 5;
if (char_time == 0)
@@ -1312,6 +1301,7 @@
if (timeout && time_after(jiffies, orig_jiffies + timeout))
break;
}
+ unlock_kernel();
#else
/*
* For the other coldfire models, assume all data has been sent
diff --git a/drivers/serial/netx-serial.c b/drivers/serial/netx-serial.c
index 3123ffe..81ac9bb 100644
--- a/drivers/serial/netx-serial.c
+++ b/drivers/serial/netx-serial.c
@@ -287,6 +287,7 @@
{
unsigned int val;
+ /* FIXME: Locking needed ? */
if (mctrl & TIOCM_RTS) {
val = readl(port->membase + UART_RTS_CR);
writel(val | RTS_CR_RTS, port->membase + UART_RTS_CR);