Ok, after screwing up the first time, and corresponding with Alan, here's
a version of the patch that should actually do something (thanks, Alan!).
Regards,
Rob Radez
diff -ruN linux-2.4.18-pre9-old/drivers/char/pcwd.c linux-2.4.18-pre9-new/drivers/char/pcwd.c
--- linux-2.4.18-pre9-old/drivers/char/pcwd.c Sun Feb 10 18:44:53 2002
+++ linux-2.4.18-pre9-new/drivers/char/pcwd.c Sun Feb 10 20:53:49 2002
@@ -40,6 +40,8 @@
* fairly useless proc entry.
* 990610 removed said useless proc code for the merge <alan>
* 000403 Removed last traces of proc code. <davej>
+ * 020210 Backported 2.5 open_allowed changes, and got rid of a useless
+ * variable <[email protected]>
*/
#include <linux/module.h>
@@ -100,7 +102,8 @@
#define WD_SRLY2 0x80 /* Software external relay triggered */
static int current_readport, revision, temp_panic;
-static int is_open, initial_status, supports_temp, mode_debug;
+static atomic_t open_allowed = ATOMIC_INIT(1);
+static int initial_status, supports_temp, mode_debug;
static spinlock_t io_lock;
/*
@@ -237,7 +240,7 @@
static int pcwd_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
- int i, cdat, rv;
+ int cdat, rv;
static struct watchdog_info ident=
{
WDIOF_OVERHEAT|WDIOF_CARDRESET,
@@ -250,8 +253,9 @@
return -ENOTTY;
case WDIOC_GETSUPPORT:
- i = copy_to_user((void*)arg, &ident, sizeof(ident));
- return i ? -EFAULT : 0;
+ if(copy_to_user((void*)arg, &ident, sizeof(ident)))
+ return -EFAULT;
+ return 0;
case WDIOC_GETSTATUS:
spin_lock(&io_lock);
@@ -402,8 +406,10 @@
switch (MINOR(ino->i_rdev))
{
case WATCHDOG_MINOR:
- if (is_open)
+ if (!atomic_dec_and_test(&open_allowed)){
+ atomic_inc(&open_allowed);
return -EBUSY;
+ }
MOD_INC_USE_COUNT;
/* Enable the port */
if (revision == PCWD_REVISION_C)
@@ -412,7 +418,6 @@
outb_p(0x00, current_readport + 3);
spin_unlock(&io_lock);
}
- is_open = 1;
return(0);
case TEMP_MINOR:
return(0);
@@ -452,8 +457,6 @@
{
if (MINOR(ino->i_rdev)==WATCHDOG_MINOR)
{
- lock_kernel();
- is_open = 0;
#ifndef CONFIG_WATCHDOG_NOWAYOUT
/* Disable the board */
if (revision == PCWD_REVISION_C) {
@@ -463,7 +466,7 @@
spin_unlock(&io_lock);
}
#endif
- unlock_kernel();
+ atomic_inc(&open_allowed);
}
return 0;
}
@@ -574,7 +577,6 @@
printk("pcwd: v%s Ken Hollis ([email protected])\n", WD_VER);
/* Initial variables */
- is_open = 0;
supports_temp = 0;
mode_debug = 0;
temp_panic = 0;