X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fs390%2Fchar%2Fvmur.c;h=83ae9a852f00c2dc5c4e2fc9be7eb81e974770de;hb=42c59208219a2d43f0dde94bebc68c20b95b13ce;hp=d70a6e65bf14fdf314dae599450d55c85e815b23;hpb=2843483d2eb02ad104edbe8b2429fb6a39d25063;p=linux-2.6-omap-h63xx.git

diff --git a/drivers/s390/char/vmur.c b/drivers/s390/char/vmur.c
index d70a6e65bf1..83ae9a852f0 100644
--- a/drivers/s390/char/vmur.c
+++ b/drivers/s390/char/vmur.c
@@ -100,7 +100,8 @@ static struct urdev *urdev_alloc(struct ccw_device *cdev)
 	urd->reclen = cdev->id.driver_info;
 	ccw_device_get_id(cdev, &urd->dev_id);
 	mutex_init(&urd->io_mutex);
-	mutex_init(&urd->open_mutex);
+	init_waitqueue_head(&urd->wait);
+	spin_lock_init(&urd->open_lock);
 	atomic_set(&urd->ref_count,  1);
 	urd->cdev = cdev;
 	get_device(&cdev->dev);
@@ -678,17 +679,21 @@ static int ur_open(struct inode *inode, struct file *file)
 	if (!urd)
 		return -ENXIO;
 
-	if (file->f_flags & O_NONBLOCK) {
-		if (!mutex_trylock(&urd->open_mutex)) {
+	spin_lock(&urd->open_lock);
+	while (urd->open_flag) {
+		spin_unlock(&urd->open_lock);
+		if (file->f_flags & O_NONBLOCK) {
 			rc = -EBUSY;
 			goto fail_put;
 		}
-	} else {
-		if (mutex_lock_interruptible(&urd->open_mutex)) {
+		if (wait_event_interruptible(urd->wait, urd->open_flag == 0)) {
 			rc = -ERESTARTSYS;
 			goto fail_put;
 		}
+		spin_lock(&urd->open_lock);
 	}
+	urd->open_flag++;
+	spin_unlock(&urd->open_lock);
 
 	TRACE("ur_open\n");
 
@@ -720,7 +725,9 @@ static int ur_open(struct inode *inode, struct file *file)
 fail_urfile_free:
 	urfile_free(urf);
 fail_unlock:
-	mutex_unlock(&urd->open_mutex);
+	spin_lock(&urd->open_lock);
+	urd->open_flag--;
+	spin_unlock(&urd->open_lock);
 fail_put:
 	urdev_put(urd);
 	return rc;
@@ -731,7 +738,10 @@ static int ur_release(struct inode *inode, struct file *file)
 	struct urfile *urf = file->private_data;
 
 	TRACE("ur_release\n");
-	mutex_unlock(&urf->urd->open_mutex);
+	spin_lock(&urf->urd->open_lock);
+	urf->urd->open_flag--;
+	spin_unlock(&urf->urd->open_lock);
+	wake_up_interruptible(&urf->urd->wait);
 	urdev_put(urf->urd);
 	urfile_free(urf);
 	return 0;
@@ -759,7 +769,7 @@ static loff_t ur_llseek(struct file *file, loff_t offset, int whence)
 	return newpos;
 }
 
-static struct file_operations ur_fops = {
+static const struct file_operations ur_fops = {
 	.owner	 = THIS_MODULE,
 	.open	 = ur_open,
 	.release = ur_release,