isdn: fix multiple sleep_on races
authorArnd Bergmann <arnd@arndb.de>
Wed, 26 Feb 2014 11:01:55 +0000 (12:01 +0100)
committerDavid S. Miller <davem@davemloft.net>
Wed, 26 Feb 2014 21:06:13 +0000 (16:06 -0500)
The isdn core code uses a couple of wait queues with
interruptible_sleep_on, which is racy and about to get
removed from the kernel. Fortunately, we know for each case
what we are waiting for, so they can all be converted to
the better wait_event_interruptible interface.

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>
drivers/isdn/i4l/isdn_common.c

index 9bb12ba3191fbdac568f9352f77dc05b66d051cc..130f216431541d2bd3259757e7765d929a91dc5a 100644 (file)
@@ -777,7 +777,8 @@ isdn_readbchan(int di, int channel, u_char *buf, u_char *fp, int len, wait_queue
                return 0;
        if (skb_queue_empty(&dev->drv[di]->rpqueue[channel])) {
                if (sleep)
-                       interruptible_sleep_on(sleep);
+                       wait_event_interruptible(*sleep,
+                               !skb_queue_empty(&dev->drv[di]->rpqueue[channel]));
                else
                        return 0;
        }
@@ -1072,7 +1073,8 @@ isdn_read(struct file *file, char __user *buf, size_t count, loff_t *off)
                                retval = -EAGAIN;
                                goto out;
                        }
-                       interruptible_sleep_on(&(dev->info_waitq));
+                       wait_event_interruptible(dev->info_waitq,
+                                                file->private_data);
                }
                p = isdn_statstr();
                file->private_data = NULL;
@@ -1128,7 +1130,8 @@ isdn_read(struct file *file, char __user *buf, size_t count, loff_t *off)
                                retval = -EAGAIN;
                                goto out;
                        }
-                       interruptible_sleep_on(&(dev->drv[drvidx]->st_waitq));
+                       wait_event_interruptible(dev->drv[drvidx]->st_waitq,
+                                                dev->drv[drvidx]->stavail);
                }
                if (dev->drv[drvidx]->interface->readstat) {
                        if (count > dev->drv[drvidx]->stavail)
@@ -1188,8 +1191,8 @@ isdn_write(struct file *file, const char __user *buf, size_t count, loff_t *off)
                        goto out;
                }
                chidx = isdn_minor2chan(minor);
-               while ((retval = isdn_writebuf_stub(drvidx, chidx, buf, count)) == 0)
-                       interruptible_sleep_on(&dev->drv[drvidx]->snd_waitq[chidx]);
+               wait_event_interruptible(dev->drv[drvidx]->snd_waitq[chidx],
+                       (retval = isdn_writebuf_stub(drvidx, chidx, buf, count)));
                goto out;
        }
        if (minor <= ISDN_MINOR_CTRLMAX) {