[S390] Automatically detect added cpus.

[linux-2.6-omap-h63xx.git] / drivers / s390 / char / vmur.c

diff --git a/drivers/s390/char/vmur.c b/drivers/s390/char/vmur.c
index d70a6e65bf14fdf314dae599450d55c85e815b23..83ae9a852f00c2dc5c4e2fc9be7eb81e974770de 100644 (file)
--- 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,