From: Patrick van de Lageweg <patrick@bitwizard.nl>
This patch converts all save_flags/restore_flags to the new
spin_lock_irqsave/spin_unlock_irqrestore calls, as well as some other 2.6.X
cleanups. This prepares the way for the "io8+", "sx" and "rio" drivers to
become SMP safe. Patches for those drivers follow.
Signed-off-by: Patrick vd Lageweg <patrick@bitwizard.nl>
Signed-off-by: Rogier Wolff <R.E.Wolff@BitWizard.nl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/drivers/char/generic_serial.c | 115 ++++++++++++++++++---------------
25-akpm/include/linux/generic_serial.h | 4 -
2 files changed, 68 insertions(+), 51 deletions(-)
diff -puN drivers/char/generic_serial.c~generic-serial-cli-conversion drivers/char/generic_serial.c
--- 25/drivers/char/generic_serial.c~generic-serial-cli-conversion 2005-01-10 21:15:26.119482816 -0800
+++ 25-akpm/drivers/char/generic_serial.c 2005-01-10 21:15:26.126481752 -0800
@@ -26,6 +26,7 @@
#include <linux/mm.h>
#include <linux/generic_serial.h>
#include <linux/interrupt.h>
+#include <linux/tty_flip.h>
#include <linux/delay.h>
#include <asm/semaphore.h>
#include <asm/uaccess.h>
@@ -45,8 +46,8 @@ static int gs_debug;
#define func_enter() gs_dprintk (GS_DEBUG_FLOW, "gs: enter %s\n", __FUNCTION__)
#define func_exit() gs_dprintk (GS_DEBUG_FLOW, "gs: exit %s\n", __FUNCTION__)
-
-#ifdef NEW_WRITE_LOCKING
+#define NEW_WRITE_LOCKING 1
+#if NEW_WRITE_LOCKING
#define DECL /* Nothing */
#define LOCKIT down (& port->port_write_sem);
#define RELEASEIT up (&port->port_write_sem);
@@ -208,7 +209,7 @@ int gs_write(struct tty_struct * tty,
if (!port || !port->xmit_buf || !tmp_buf)
return -EIO;
- save_flags(flags);
+ local_save_flags(flags);
while (1) {
cli();
c = count;
@@ -227,14 +228,14 @@ int gs_write(struct tty_struct * tty,
/* Can't copy more? break out! */
if (c <= 0) {
- restore_flags(flags);
+ local_restore_flags(flags);
break;
}
memcpy(port->xmit_buf + port->xmit_head, buf, c);
port->xmit_head = ((port->xmit_head + c) &
(SERIAL_XMIT_SIZE-1));
port->xmit_cnt += c;
- restore_flags(flags);
+ local_restore_flags(flags);
buf += c;
count -= c;
total += c;
@@ -380,9 +381,9 @@ void gs_flush_buffer(struct tty_struct *
if (!port) return;
/* XXX Would the write semaphore do? */
- save_flags(flags); cli();
+ spin_lock_irqsave (&port->driver_lock, flags);
port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
- restore_flags(flags);
+ spin_unlock_irqrestore (&port->driver_lock, flags);
wake_up_interruptible(&tty->write_wait);
tty_wakeup(tty);
@@ -468,8 +469,7 @@ static void gs_shutdown_port (struct gs_
if (!(port->flags & ASYNC_INITIALIZED))
return;
- save_flags (flags);
- cli ();
+ spin_lock_irqsave(&port->driver_lock, flags);
if (port->xmit_buf) {
free_page((unsigned long) port->xmit_buf);
@@ -482,7 +482,7 @@ static void gs_shutdown_port (struct gs_
port->rd->shutdown_port (port);
port->flags &= ~ASYNC_INITIALIZED;
- restore_flags (flags);
+ spin_unlock_irqrestore(&port->driver_lock, flags);
func_exit();
}
@@ -519,6 +519,7 @@ int gs_block_til_ready(void *port_, stru
int do_clocal = 0;
int CD;
struct tty_struct *tty;
+ unsigned long flags;
func_enter ();
@@ -570,10 +571,11 @@ int gs_block_til_ready(void *port_, stru
add_wait_queue(&port->open_wait, &wait);
gs_dprintk (GS_DEBUG_BTR, "after add waitq.\n");
- cli();
- if (!tty_hung_up_p(filp))
+ spin_lock_irqsave(&port->driver_lock, flags);
+ if (!tty_hung_up_p(filp)) {
port->count--;
- sti();
+ }
+ spin_unlock_irqrestore(&port->driver_lock, flags);
port->blocked_open++;
while (1) {
CD = port->rd->get_CD (port);
@@ -602,8 +604,9 @@ int gs_block_til_ready(void *port_, stru
port->blocked_open);
set_current_state (TASK_RUNNING);
remove_wait_queue(&port->open_wait, &wait);
- if (!tty_hung_up_p(filp))
+ if (!tty_hung_up_p(filp)) {
port->count++;
+ }
port->blocked_open--;
if (retval)
return retval;
@@ -633,27 +636,29 @@ void gs_close(struct tty_struct * tty, s
port->tty = tty;
}
- save_flags(flags); cli();
+ spin_lock_irqsave(&port->driver_lock, flags);
if (tty_hung_up_p(filp)) {
- restore_flags(flags);
- port->rd->hungup (port);
+ spin_unlock_irqrestore(&port->driver_lock, flags);
+ if (port->rd->hungup)
+ port->rd->hungup (port);
func_exit ();
return;
}
if ((tty->count == 1) && (port->count != 1)) {
- printk(KERN_ERR "gs: gs_close: bad port count;"
- " tty->count is 1, port count is %d\n", port->count);
+ printk(KERN_ERR "gs: gs_close port %p: bad port count;"
+ " tty->count is 1, port count is %d\n", port, port->count);
port->count = 1;
}
if (--port->count < 0) {
- printk(KERN_ERR "gs: gs_close: bad port count: %d\n", port->count);
+ printk(KERN_ERR "gs: gs_close port %p: bad port count: %d\n", port, port->count);
port->count = 0;
}
+
if (port->count) {
- gs_dprintk(GS_DEBUG_CLOSE, "gs_close: count: %d\n", port->count);
- restore_flags(flags);
+ gs_dprintk(GS_DEBUG_CLOSE, "gs_close port %p: count: %d\n", port, port->count);
+ spin_unlock_irqrestore(&port->driver_lock, flags);
func_exit ();
return;
}
@@ -675,16 +680,17 @@ void gs_close(struct tty_struct * tty, s
*/
port->rd->disable_rx_interrupts (port);
+ spin_unlock_irqrestore(&port->driver_lock, flags);
/* close has no way of returning "EINTR", so discard return value */
if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
- gs_wait_tx_flushed (port, port->closing_wait);
+ gs_wait_tx_flushed (port, port->closing_wait);
port->flags &= ~GS_ACTIVE;
if (tty->driver->flush_buffer)
tty->driver->flush_buffer(tty);
-
+
tty_ldisc_flush(tty);
tty->closing = 0;
@@ -695,14 +701,15 @@ void gs_close(struct tty_struct * tty, s
if (port->blocked_open) {
if (port->close_delay) {
+ spin_unlock_irqrestore(&port->driver_lock, flags);
msleep_interruptible(jiffies_to_msecs(port->close_delay));
+ spin_lock_irqsave(&port->driver_lock, flags);
}
wake_up_interruptible(&port->open_wait);
}
port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING | ASYNC_INITIALIZED);
wake_up_interruptible(&port->close_wait);
- restore_flags(flags);
func_exit ();
}
@@ -727,6 +734,12 @@ void gs_set_termios (struct tty_struct *
port = tty->driver_data;
if (!port) return;
+ if (!port->tty) {
+ /* This seems to happen when this is called after gs_close. */
+ gs_dprintk (GS_DEBUG_TERMIOS, "gs: Odd: port->tty is NULL\n");
+ port->tty = tty;
+ }
+
tiosp = tty->termios;
@@ -821,7 +834,7 @@ void gs_set_termios (struct tty_struct *
if (!(old_termios->c_cflag & CLOCAL) &&
(tty->termios->c_cflag & CLOCAL))
- wake_up_interruptible(&info->open_wait);
+ wake_up_interruptible(&port->gs.open_wait);
#endif
func_exit();
@@ -836,56 +849,56 @@ int gs_init_port(struct gs_port *port)
unsigned long flags;
unsigned long page;
- save_flags (flags);
- if (!tmp_buf) {
- page = get_zeroed_page(GFP_KERNEL);
+ func_enter ();
- cli (); /* Don't expect this to make a difference. */
+ if (!tmp_buf) {
+ page = get_zeroed_page(GFP_KERNEL);
+ spin_lock_irqsave (&port->driver_lock, flags); /* Don't expect this to make a difference. */
if (tmp_buf)
free_page(page);
else
tmp_buf = (unsigned char *) page;
- restore_flags (flags);
-
+ spin_unlock_irqrestore (&port->driver_lock, flags);
if (!tmp_buf) {
+ func_exit ();
return -ENOMEM;
}
}
- if (port->flags & ASYNC_INITIALIZED)
+ if (port->flags & ASYNC_INITIALIZED) {
+ func_exit ();
return 0;
-
+ }
if (!port->xmit_buf) {
/* We may sleep in get_zeroed_page() */
unsigned long tmp;
tmp = get_zeroed_page(GFP_KERNEL);
-
- /* Spinlock? */
- cli ();
+ spin_lock_irqsave (&port->driver_lock, flags);
if (port->xmit_buf)
free_page (tmp);
else
port->xmit_buf = (unsigned char *) tmp;
- restore_flags (flags);
-
- if (!port->xmit_buf)
+ spin_unlock_irqrestore(&port->driver_lock, flags);
+ if (!port->xmit_buf) {
+ func_exit ();
return -ENOMEM;
+ }
}
- cli();
-
+ spin_lock_irqsave (&port->driver_lock, flags);
if (port->tty)
clear_bit(TTY_IO_ERROR, &port->tty->flags);
-
+ init_MUTEX(&port->port_write_sem);
port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
-
+ spin_unlock_irqrestore(&port->driver_lock, flags);
gs_set_termios(port->tty, NULL);
-
+ spin_lock_irqsave (&port->driver_lock, flags);
port->flags |= ASYNC_INITIALIZED;
port->flags &= ~GS_TX_INTEN;
- restore_flags(flags);
+ spin_unlock_irqrestore(&port->driver_lock, flags);
+ func_exit ();
return 0;
}
@@ -956,13 +969,15 @@ int gs_getserial(struct gs_port *port, s
void gs_got_break(struct gs_port *port)
{
+ func_enter ();
+
+ tty_insert_flip_char(port->tty, 0, TTY_BREAK);
+ tty_schedule_flip(port->tty);
if (port->flags & ASYNC_SAK) {
do_SAK (port->tty);
}
- *(port->tty->flip.flag_buf_ptr) = TTY_BREAK;
- port->tty->flip.flag_buf_ptr++;
- port->tty->flip.char_buf_ptr++;
- port->tty->flip.count++;
+
+ func_exit ();
}
diff -puN include/linux/generic_serial.h~generic-serial-cli-conversion include/linux/generic_serial.h
--- 25/include/linux/generic_serial.h~generic-serial-cli-conversion 2005-01-10 21:15:26.120482664 -0800
+++ 25-akpm/include/linux/generic_serial.h 2005-01-10 21:15:26.127481600 -0800
@@ -34,7 +34,7 @@ struct gs_port {
int xmit_head;
int xmit_tail;
int xmit_cnt;
- /* struct semaphore port_write_sem; */
+ struct semaphore port_write_sem;
int flags;
wait_queue_head_t open_wait;
wait_queue_head_t close_wait;
@@ -49,6 +49,7 @@ struct gs_port {
int baud_base;
int baud;
int custom_divisor;
+ spinlock_t driver_lock;
};
@@ -70,6 +71,7 @@ struct gs_port {
#define GS_DEBUG_STUFF 0x00000008
#define GS_DEBUG_CLOSE 0x00000010
#define GS_DEBUG_FLOW 0x00000020
+#define GS_DEBUG_WRITE 0x00000040
void gs_put_char(struct tty_struct *tty, unsigned char ch);
_