[PATCH] drivers/char/riscom8.c: cli/sti removal

From: Felipe W Damasio (felipewd@terra.com.br)
Date: Wed Jul 30 2003 - 12:47:56 EST


        Hi,

        Since Dmitry Gorodchanin doesn't have a valid email, I'm sending this
directly here.

        This patch, against 2.6-test2, replaces {save|restore}_flags and cli
with lock spinlocks on the RISCom/8 multiport serial driver.

        Please consider applying.

        Thanks,

Felipe


--- linux-2.6.0-test2/drivers/char/riscom8.c.orig Wed Jul 30 14:39:11 2003
+++ linux-2.6.0-test2/drivers/char/riscom8.c Wed Jul 30 14:42:44 2003
@@ -29,6 +29,9 @@
  * ChangeLog:
  * Arnaldo Carvalho de Melo <acme@conectiva.com.br> - 27-Jun-2001
  * - get rid of check_region and several cleanups
+ *
+ * Felipe Damasio <felipewd@terra.com.br> - 30-Jul-2003
+ * - Fixed SMP support by removing {save|restore}_flags, cli/sti
  */
 
 #include <linux/module.h>
@@ -45,6 +48,7 @@
 #include <linux/fcntl.h>
 #include <linux/major.h>
 #include <linux/init.h>
+#include <linux/spinlock.h>
 
 #include <asm/uaccess.h>
 
@@ -88,6 +92,8 @@
 static unsigned char * tmp_buf;
 static DECLARE_MUTEX(tmp_buf_sem);
 
+static spinlock_t rc_lock = SPIN_LOCK_UNLOCKED;
+
 static unsigned long baud_table[] = {
         0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
         9600, 19200, 38400, 57600, 76800, 0,
@@ -237,13 +243,13 @@
 {
         unsigned long flags;
         
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
         rc_out(bp, RC_CTOUT, 0); /* Clear timeout */
         rc_wait_CCR(bp); /* Wait for CCR ready */
         rc_out(bp, CD180_CCR, CCR_HARDRESET); /* Reset CD180 chip */
- sti();
+ spin_unlock_irqsave(&rc_lock, flags);
         rc_long_delay(HZ/20); /* Delay 0.05 sec */
- cli();
+ spin_lock_irqsave(&rc_lock, flags);
         rc_out(bp, CD180_GIVR, RC_ID); /* Set ID for this chip */
         rc_out(bp, CD180_GICR, 0); /* Clear all bits */
         rc_out(bp, CD180_PILR1, RC_ACK_MINT); /* Prio for modem intr */
@@ -253,8 +259,8 @@
         /* Setting up prescaler. We need 4 ticks per 1 ms */
         rc_out(bp, CD180_PPRH, (RC_OSCFREQ/(1000000/RISCOM_TPS)) >> 8);
         rc_out(bp, CD180_PPRL, (RC_OSCFREQ/(1000000/RISCOM_TPS)) & 0xff);
-
- restore_flags(flags);
+
+ spin_unlock_irqsave(&rc_lock, flags);
 }
 
 /* Main probing routine, also sets irq. */
@@ -875,7 +881,7 @@
                 port->xmit_buf = (unsigned char *) tmp;
         }
                 
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
                 
         if (port->tty)
                 clear_bit(TTY_IO_ERROR, &port->tty->flags);
@@ -886,8 +892,8 @@
         port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
         rc_change_speed(bp, port);
         port->flags |= ASYNC_INITIALIZED;
-
- restore_flags(flags);
+
+ spin_unlock_irqsave(&rc_lock, flags);
         return 0;
 }
 
@@ -998,19 +1004,19 @@
          */
         retval = 0;
         add_wait_queue(&port->open_wait, &wait);
- cli();
+ spin_lock(&rc_lock);
         if (!tty_hung_up_p(filp))
                 port->count--;
- sti();
+ spin_unlock(&rc_lock);
         port->blocked_open++;
         while (1) {
- cli();
+ spin_lock(&rc_lock);
                 rc_out(bp, CD180_CAR, port_No(port));
                 CD = rc_in(bp, CD180_MSVR) & MSVR_CD;
                 rc_out(bp, CD180_MSVR, MSVR_RTS);
                 bp->DTR &= ~(1u << port_No(port));
                 rc_out(bp, RC_DTR, bp->DTR);
- sti();
+ spin_unlock(&rc_lock);
                 set_current_state(TASK_INTERRUPTIBLE);
                 if (tty_hung_up_p(filp) ||
                     !(port->flags & ASYNC_INITIALIZED)) {
@@ -1084,7 +1090,7 @@
         if (!port || rc_paranoia_check(port, tty->name, "close"))
                 return;
         
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
         if (tty_hung_up_p(filp))
                 goto out;
         
@@ -1153,7 +1159,7 @@
         }
         port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
         wake_up_interruptible(&port->close_wait);
-out: restore_flags(flags);
+out: spin_unlock_irqsave(&rc_lock, flags);
 }
 
 static int rc_write(struct tty_struct * tty, int from_user,
@@ -1172,30 +1178,31 @@
         if (!tty || !port->xmit_buf || !tmp_buf)
                 return 0;
 
- save_flags(flags);
         if (from_user) {
                 down(&tmp_buf_sem);
                 while (1) {
- cli();
+ spin_lock_irqsave(&rc_lock, flags);
                         c = MIN(count, MIN(SERIAL_XMIT_SIZE - port->xmit_cnt - 1,
                                            SERIAL_XMIT_SIZE - port->xmit_head));
- if (c <= 0)
+ if (c <= 0){
+ spin_unlock_irqsave(&rc_lock, flags);
                                 break;
+ }
 
                         c -= copy_from_user(tmp_buf, buf, c);
                         if (!c) {
                                 if (!total)
                                         total = -EFAULT;
+ spin_unlock_irqsave(&rc_lock, flags);
                                 break;
                         }
 
- cli();
                         c = MIN(c, MIN(SERIAL_XMIT_SIZE - port->xmit_cnt - 1,
                                        SERIAL_XMIT_SIZE - port->xmit_head));
                         memcpy(port->xmit_buf + port->xmit_head, tmp_buf, c);
                         port->xmit_head = (port->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
                         port->xmit_cnt += c;
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
 
                         buf += c;
                         count -= c;
@@ -1204,18 +1211,18 @@
                 up(&tmp_buf_sem);
         } else {
                 while (1) {
- cli();
+ spin_lock_irqsave(&rc_lock, flags);
                         c = MIN(count, MIN(SERIAL_XMIT_SIZE - port->xmit_cnt - 1,
                                            SERIAL_XMIT_SIZE - port->xmit_head));
                         if (c <= 0) {
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, 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);
+ spin_unlock_irqsave(&rc_lock, flags);
 
                         buf += c;
                         count -= c;
@@ -1223,14 +1230,14 @@
                 }
         }
 
- cli();
+ spin_lock_irqsave(&rc_lock, flags);
         if (port->xmit_cnt && !tty->stopped && !tty->hw_stopped &&
             !(port->IER & IER_TXRDY)) {
                 port->IER |= IER_TXRDY;
                 rc_out(bp, CD180_CAR, port_No(port));
                 rc_out(bp, CD180_IER, port->IER);
         }
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
 
         return total;
 }
@@ -1246,7 +1253,7 @@
         if (!tty || !port->xmit_buf)
                 return;
 
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
         
         if (port->xmit_cnt >= SERIAL_XMIT_SIZE - 1)
                 goto out;
@@ -1254,7 +1261,7 @@
         port->xmit_buf[port->xmit_head++] = ch;
         port->xmit_head &= SERIAL_XMIT_SIZE - 1;
         port->xmit_cnt++;
-out: restore_flags(flags);
+out: spin_unlock_irqsave(&rc_lock, flags);
 }
 
 static void rc_flush_chars(struct tty_struct * tty)
@@ -1269,11 +1276,11 @@
             !port->xmit_buf)
                 return;
 
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
         port->IER |= IER_TXRDY;
         rc_out(port_Board(port), CD180_CAR, port_No(port));
         rc_out(port_Board(port), CD180_IER, port->IER);
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
 }
 
 static int rc_write_room(struct tty_struct * tty)
@@ -1308,9 +1315,9 @@
         if (rc_paranoia_check(port, tty->name, "rc_flush_buffer"))
                 return;
 
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
         port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
         
         wake_up_interruptible(&tty->write_wait);
         if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
@@ -1326,11 +1333,11 @@
         unsigned long flags;
 
         bp = port_Board(port);
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
         rc_out(bp, CD180_CAR, port_No(port));
         status = rc_in(bp, CD180_MSVR);
         result = rc_in(bp, RC_RI) & (1u << port_No(port)) ? 0 : TIOCM_RNG;
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
         result |= ((status & MSVR_RTS) ? TIOCM_RTS : 0)
                 | ((status & MSVR_DTR) ? TIOCM_DTR : 0)
                 | ((status & MSVR_CD) ? TIOCM_CAR : 0)
@@ -1370,11 +1377,11 @@
          default:
                 return -EINVAL;
         }
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
         rc_out(bp, CD180_CAR, port_No(port));
         rc_out(bp, CD180_MSVR, port->MSVR);
         rc_out(bp, RC_DTR, bp->DTR);
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
         return 0;
 }
 
@@ -1383,7 +1390,7 @@
         struct riscom_board *bp = port_Board(port);
         unsigned long flags;
         
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
         port->break_length = RISCOM_TPS / HZ * length;
         port->COR2 |= COR2_ETC;
         port->IER |= IER_TXRDY;
@@ -1393,7 +1400,7 @@
         rc_wait_CCR(bp);
         rc_out(bp, CD180_CCR, CCR_CORCHG2);
         rc_wait_CCR(bp);
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
 }
 
 static inline int rc_set_serial_info(struct riscom_port * port,
@@ -1436,9 +1443,9 @@
                 port->closing_wait = tmp.closing_wait;
         }
         if (change_speed) {
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
                 rc_change_speed(bp, port);
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
         }
         return 0;
 }
@@ -1524,7 +1531,7 @@
         
         bp = port_Board(port);
         
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
         port->MSVR &= ~MSVR_RTS;
         rc_out(bp, CD180_CAR, port_No(port));
         if (I_IXOFF(tty)) {
@@ -1533,7 +1540,7 @@
                 rc_wait_CCR(bp);
         }
         rc_out(bp, CD180_MSVR, port->MSVR);
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
 }
 
 static void rc_unthrottle(struct tty_struct * tty)
@@ -1547,7 +1554,7 @@
         
         bp = port_Board(port);
         
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
         port->MSVR |= MSVR_RTS;
         rc_out(bp, CD180_CAR, port_No(port));
         if (I_IXOFF(tty)) {
@@ -1556,7 +1563,7 @@
                 rc_wait_CCR(bp);
         }
         rc_out(bp, CD180_MSVR, port->MSVR);
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
 }
 
 static void rc_stop(struct tty_struct * tty)
@@ -1570,11 +1577,11 @@
         
         bp = port_Board(port);
         
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
         port->IER &= ~IER_TXRDY;
         rc_out(bp, CD180_CAR, port_No(port));
         rc_out(bp, CD180_IER, port->IER);
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
 }
 
 static void rc_start(struct tty_struct * tty)
@@ -1588,13 +1595,13 @@
         
         bp = port_Board(port);
         
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
         if (port->xmit_cnt && port->xmit_buf && !(port->IER & IER_TXRDY)) {
                 port->IER |= IER_TXRDY;
                 rc_out(bp, CD180_CAR, port_No(port));
                 rc_out(bp, CD180_IER, port->IER);
         }
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
 }
 
 /*
@@ -1646,9 +1653,9 @@
             tty->termios->c_iflag == old_termios->c_iflag)
                 return;
 
- save_flags(flags); cli();
+ spin_lock_irqsave(&rc_lock, flags);
         rc_change_speed(port_Board(port), port);
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
 
         if ((old_termios->c_cflag & CRTSCTS) &&
             !(tty->termios->c_cflag & CRTSCTS)) {
@@ -1751,13 +1758,12 @@
 {
         unsigned long flags;
 
- save_flags(flags);
- cli();
+ spin_lock_irqsave(&rc_lock, flags);
         remove_bh(RISCOM8_BH);
         free_page((unsigned long)tmp_buf);
         tty_unregister_driver(riscom_driver);
         put_tty_driver(riscom_driver);
- restore_flags(flags);
+ spin_unlock_irqsave(&rc_lock, flags);
 }
 
 #ifndef MODULE

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This archive was generated by hypermail 2b29 : Thu Jul 31 2003 - 22:00:46 EST