Commit 197cec28 authored by Julian Wiedmann's avatar Julian Wiedmann Committed by Vasily Gorbik
Browse files

s390/ccwgroup: release the cdevs from within dev->release() 



Wiring up the cdevs is an essential part of the gdev creation. So
release them during the gdev destruction, ie. on the last put_device().
This could cause us to hold on to the cdevs a tiny bit longer, but
that's not a real concern.

As we have much less certainty of what context this put_device() is
executed from, switch to irqsave locking.

Signed-off-by: default avatarJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent 95c09f03

drivers/s390/cio/ccwgroup.c

+17 −32
Original line number Diff line number Diff line
@@ -45,27 +45,6 @@ static void __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);

	}

}



/**

 * ccwgroup_set_online() - enable a ccwgroup device

 * @gdev: target ccwgroup device
@@ -175,7 +154,6 @@ static void ccwgroup_ungroup(struct ccwgroup_device *gdev) 
	if (device_is_registered(&gdev->dev)) {

		__ccwgroup_remove_symlinks(gdev);

		device_unregister(&gdev->dev);

		__ccwgroup_remove_cdev_refs(gdev);

	}

	mutex_unlock(&gdev->reg_mutex);

}
@@ -228,7 +206,23 @@ static void ccwgroup_ungroup_workfn(struct work_struct *work) 


static void ccwgroup_release(struct device *dev)

{

	kfree(to_ccwgroupdev(dev));

	struct ccwgroup_device *gdev = to_ccwgroupdev(dev);

	unsigned int i;



	for (i = 0; i < gdev->count; i++) {

		struct ccw_device *cdev = gdev->cdev[i];

		unsigned long flags;



		if (cdev) {

			spin_lock_irqsave(cdev->ccwlock, flags);

			if (dev_get_drvdata(&cdev->dev) == gdev)

				dev_set_drvdata(&cdev->dev, NULL);

			spin_unlock_irqrestore(cdev->ccwlock, flags);

			put_device(&cdev->dev);

		}

	}



	kfree(gdev);

}



static int __ccwgroup_create_symlinks(struct ccwgroup_device *gdev)
@@ -396,15 +390,6 @@ int ccwgroup_create_dev(struct device *parent, struct ccwgroup_driver *gdrv, 
	mutex_unlock(&gdev->reg_mutex);

	return 0;

error:

	for (i = 0; i < num_devices; 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);

			gdev->cdev[i] = NULL;

		}

	mutex_unlock(&gdev->reg_mutex);

	put_device(&gdev->dev);

	return rc;