isdn: divert, hysdn: fix interruptible_sleep_on race
These two drivers use identical code for their procfs status
file handling, which contains a small race against status
data becoming available while reading the file.
This uses wait_event_interruptible instead to fix this
particular race and eventually get rid of all sleep_on
instances. There seems to be another race involving
multiple concurrent readers of the same procfs file, which
I don't try to fix here.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/isdn/divert/divert_procfs.c b/drivers/isdn/divert/divert_procfs.c
index fb4f1ba..1c5dc34 100644
--- a/drivers/isdn/divert/divert_procfs.c
+++ b/drivers/isdn/divert/divert_procfs.c
@@ -86,12 +86,13 @@
struct divert_info *inf;
int len;
- if (!*((struct divert_info **) file->private_data)) {
+ if (!(inf = *((struct divert_info **) file->private_data))) {
if (file->f_flags & O_NONBLOCK)
return -EAGAIN;
- interruptible_sleep_on(&(rd_queue));
+ wait_event_interruptible(rd_queue, (inf =
+ *((struct divert_info **) file->private_data)));
}
- if (!(inf = *((struct divert_info **) file->private_data)))
+ if (!inf)
return (0);
inf->usage_cnt--; /* new usage count */