Merge tag 'v2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

[mv-sheeva.git] / drivers / s390 / cio / ccwgroup.c

diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c
index 97b25d68e3e72c74c53994abf7cc140795774525..2864581d8ecb88a9d9ce362e6fbb170a57a49f46 100644 (file)
--- a/drivers/s390/cio/ccwgroup.c
+++ b/drivers/s390/cio/ccwgroup.c
@@ -66,6 +66,27 @@ __ccwgroup_remove_symlinks(struct ccwgroup_device *gdev)
        
 }
 
+/*
+ * Remove references from ccw devices to ccw group device and from
+ * ccw group device to ccw devices.
+ */
+static void __ccwgroup_remove_cdev_refs(struct ccwgroup_device *gdev)
+{
+       struct ccw_device *cdev;
+       int i;
+
+       for (i = 0; i < gdev->count; i++) {
+               cdev = gdev->cdev[i];
+               if (!cdev)
+                       continue;
+               spin_lock_irq(cdev->ccwlock);
+               dev_set_drvdata(&cdev->dev, NULL);
+               spin_unlock_irq(cdev->ccwlock);
+               gdev->cdev[i] = NULL;
+               put_device(&cdev->dev);
+       }
+}
+
 /*
  * Provide an 'ungroup' attribute so the user can remove group devices no
  * longer needed or accidentially created. Saves memory :)
@@ -78,6 +99,7 @@ static void ccwgroup_ungroup_callback(struct device *dev)
        if (device_is_registered(&gdev->dev)) {
                __ccwgroup_remove_symlinks(gdev);
                device_unregister(dev);
+               __ccwgroup_remove_cdev_refs(gdev);
        }
        mutex_unlock(&gdev->reg_mutex);
 }
@@ -116,21 +138,7 @@ static DEVICE_ATTR(ungroup, 0200, NULL, ccwgroup_ungroup_store);
 static void
 ccwgroup_release (struct device *dev)
 {
-       struct ccwgroup_device *gdev;
-       int i;
-
-       gdev = to_ccwgroupdev(dev);
-
-       for (i = 0; i < gdev->count; i++) {
-               if (gdev->cdev[i]) {
-                       spin_lock_irq(gdev->cdev[i]->ccwlock);
-                       if (dev_get_drvdata(&gdev->cdev[i]->dev) == gdev)
-                               dev_set_drvdata(&gdev->cdev[i]->dev, NULL);
-                       spin_unlock_irq(gdev->cdev[i]->ccwlock);
-                       put_device(&gdev->cdev[i]->dev);
-               }
-       }
-       kfree(gdev);
+       kfree(to_ccwgroupdev(dev));
 }
 
 static int
@@ -639,6 +647,7 @@ void ccwgroup_driver_unregister(struct ccwgroup_driver *cdriver)
                mutex_lock(&gdev->reg_mutex);
                __ccwgroup_remove_symlinks(gdev);
                device_unregister(dev);
+               __ccwgroup_remove_cdev_refs(gdev);
                mutex_unlock(&gdev->reg_mutex);
                put_device(dev);
        }
@@ -660,25 +669,6 @@ int ccwgroup_probe_ccwdev(struct ccw_device *cdev)
        return 0;
 }
 
-static struct ccwgroup_device *
-__ccwgroup_get_gdev_by_cdev(struct ccw_device *cdev)
-{
-       struct ccwgroup_device *gdev;
-
-       gdev = dev_get_drvdata(&cdev->dev);
-       if (gdev) {
-               if (get_device(&gdev->dev)) {
-                       mutex_lock(&gdev->reg_mutex);
-                       if (device_is_registered(&gdev->dev))
-                               return gdev;
-                       mutex_unlock(&gdev->reg_mutex);
-                       put_device(&gdev->dev);
-               }
-               return NULL;
-       }
-       return NULL;
-}
-
 /**
  * ccwgroup_remove_ccwdev() - remove function for slave devices
  * @cdev: ccw device to be removed
@@ -694,13 +684,25 @@ void ccwgroup_remove_ccwdev(struct ccw_device *cdev)
        /* Ignore offlining errors, device is gone anyway. */
        ccw_device_set_offline(cdev);
        /* If one of its devices is gone, the whole group is done for. */
-       gdev = __ccwgroup_get_gdev_by_cdev(cdev);
-       if (gdev) {
+       spin_lock_irq(cdev->ccwlock);
+       gdev = dev_get_drvdata(&cdev->dev);
+       if (!gdev) {
+               spin_unlock_irq(cdev->ccwlock);
+               return;
+       }
+       /* Get ccwgroup device reference for local processing. */
+       get_device(&gdev->dev);
+       spin_unlock_irq(cdev->ccwlock);
+       /* Unregister group device. */
+       mutex_lock(&gdev->reg_mutex);
+       if (device_is_registered(&gdev->dev)) {
                __ccwgroup_remove_symlinks(gdev);
                device_unregister(&gdev->dev);
-               mutex_unlock(&gdev->reg_mutex);
-               put_device(&gdev->dev);
+               __ccwgroup_remove_cdev_refs(gdev);
        }
+       mutex_unlock(&gdev->reg_mutex);
+       /* Release ccwgroup device reference for local processing. */
+       put_device(&gdev->dev);
 }
 
 MODULE_LICENSE("GPL");