linux 2.6.16.38 w/ vs2.0.3-rc1

[linux-2.6.git] / drivers / char / synclink.c

diff --git a/drivers/char/synclink.c b/drivers/char/synclink.c
index dc81260..ede688a 100644 (file)
--- a/drivers/char/synclink.c
+++ b/drivers/char/synclink.c
@@ -63,6 +63,7 @@
 #define MAX_PCI_DEVICES 10
 #define MAX_TOTAL_DEVICES 20
 
+#include <linux/config.h>      
 #include <linux/module.h>
 #include <linux/errno.h>
 #include <linux/signal.h>
@@ -940,6 +941,17 @@ static void* mgsl_get_text_ptr(void)
        return mgsl_get_text_ptr;
 }
 
+/*
+ * tmp_buf is used as a temporary buffer by mgsl_write.  We need to
+ * lock it in case the COPY_FROM_USER blocks while swapping in a page,
+ * and some other program tries to do a serial write at the same time.
+ * Since the lock will only come under contention when the system is
+ * swapping and available memory is low, it makes sense to share one
+ * buffer across all the serial ioports, since it significantly saves
+ * memory if large numbers of serial ports are open.
+ */
+static unsigned char *tmp_buf;
+
 static inline int mgsl_paranoia_check(struct mgsl_struct *info,
                                        char *name, const char *routine)
 {
@@ -1343,12 +1355,8 @@ static void mgsl_isr_io_pin( struct mgsl_struct *info )
                        } else
                                info->input_signal_events.dcd_down++;
 #ifdef CONFIG_HDLC
-                       if (info->netcount) {
-                               if (status & MISCSTATUS_DCD)
-                                       netif_carrier_on(info->netdev);
-                               else
-                                       netif_carrier_off(info->netdev);
-                       }
+                       if (info->netcount)
+                               hdlc_set_carrier(status & MISCSTATUS_DCD, info->netdev);
 #endif
                }
                if (status & MISCSTATUS_CTS_LATCHED)
@@ -2142,7 +2150,7 @@ static int mgsl_write(struct tty_struct * tty,
        if (mgsl_paranoia_check(info, tty->name, "mgsl_write"))
                goto cleanup;
 
-       if (!tty || !info->xmit_buf)
+       if (!tty || !info->xmit_buf || !tmp_buf)
                goto cleanup;
 
        if ( info->params.mode == MGSL_MODE_HDLC ||
@@ -3430,6 +3438,7 @@ static int mgsl_open(struct tty_struct *tty, struct file * filp)
 {
        struct mgsl_struct      *info;
        int                     retval, line;
+       unsigned long           page;
        unsigned long flags;
 
        /* verify range of specified line number */     
@@ -3463,6 +3472,18 @@ static int mgsl_open(struct tty_struct *tty, struct file * filp)
                goto cleanup;
        }
        
+       if (!tmp_buf) {
+               page = get_zeroed_page(GFP_KERNEL);
+               if (!page) {
+                       retval = -ENOMEM;
+                       goto cleanup;
+               }
+               if (tmp_buf)
+                       free_page(page);
+               else
+                       tmp_buf = (unsigned char *) page;
+       }
+       
        info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
        spin_lock_irqsave(&info->netlock, flags);
@@ -4481,6 +4502,11 @@ static void synclink_cleanup(void)
                kfree(tmp);
        }
        
+       if (tmp_buf) {
+               free_page((unsigned long) tmp_buf);
+               tmp_buf = NULL;
+       }
+       
        if (pci_registered)
                pci_unregister_driver(&synclink_pci_driver);
 }
@@ -5999,7 +6025,7 @@ static void usc_set_async_mode( struct mgsl_struct *info )
         * <15..8>      ?               RxFIFO IRQ Request Level
         *
         * Note: For async mode the receive FIFO level must be set
-        * to 0 to avoid the situation where the FIFO contains fewer bytes
+        * to 0 to aviod the situation where the FIFO contains fewer bytes
         * than the trigger level and no more data is expected.
         *
         * <7>          0               Exited Hunt IA (Interrupt Arm)
@@ -7744,7 +7770,7 @@ static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
        }
 
        info->params.encoding = new_encoding;
-       info->params.crc_type = new_crctype;
+       info->params.crc_type = new_crctype;;
 
        /* if network interface up, reprogram hardware */
        if (info->netcount)
@@ -7847,10 +7873,8 @@ static int hdlcdev_open(struct net_device *dev)
        spin_lock_irqsave(&info->irq_spinlock, flags);
        usc_get_serial_signals(info);
        spin_unlock_irqrestore(&info->irq_spinlock, flags);
-       if (info->serial_signals & SerialSignal_DCD)
-               netif_carrier_on(dev);
-       else
-               netif_carrier_off(dev);
+       hdlc_set_carrier(info->serial_signals & SerialSignal_DCD, dev);
+
        return 0;
 }
 
@@ -8155,7 +8179,7 @@ static int __devinit synclink_init_one (struct pci_dev *dev,
                                
        info->bus_type = MGSL_BUS_TYPE_PCI;
        info->io_addr_size = 8;
-       info->irq_flags = IRQF_SHARED;
+       info->irq_flags = SA_SHIRQ;
 
        if (dev->device == 0x0210) {
                /* Version 1 PCI9030 based universal PCI adapter */