mm: remove the struct hmm_device infrastructure

This code is a trivial wrapper around device model helpers, which
should have been integrated into the driver device model usage from
the start.  Assuming it actually had users, which it never had since
the code was added more than 1 1/2 years ago.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 0 insertions, 80 deletions

diff --git a/mm/hmm.c b/mm/hmm.c
index f702a3895d05..00cc642b3d7e 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -1528,84 +1528,4 @@ struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops,
 	return devmem;
 }
 EXPORT_SYMBOL_GPL(hmm_devmem_add_resource);
-
-/*
- * A device driver that wants to handle multiple devices memory through a
- * single fake device can use hmm_device to do so. This is purely a helper
- * and it is not needed to make use of any HMM functionality.
- */
-#define HMM_DEVICE_MAX 256
-
-static DECLARE_BITMAP(hmm_device_mask, HMM_DEVICE_MAX);
-static DEFINE_SPINLOCK(hmm_device_lock);
-static struct class *hmm_device_class;
-static dev_t hmm_device_devt;
-
-static void hmm_device_release(struct device *device)
-{
-	struct hmm_device *hmm_device;
-
-	hmm_device = container_of(device, struct hmm_device, device);
-	spin_lock(&hmm_device_lock);
-	clear_bit(hmm_device->minor, hmm_device_mask);
-	spin_unlock(&hmm_device_lock);
-
-	kfree(hmm_device);
-}
-
-struct hmm_device *hmm_device_new(void *drvdata)
-{
-	struct hmm_device *hmm_device;
-
-	hmm_device = kzalloc(sizeof(*hmm_device), GFP_KERNEL);
-	if (!hmm_device)
-		return ERR_PTR(-ENOMEM);
-
-	spin_lock(&hmm_device_lock);
-	hmm_device->minor = find_first_zero_bit(hmm_device_mask, HMM_DEVICE_MAX);
-	if (hmm_device->minor >= HMM_DEVICE_MAX) {
-		spin_unlock(&hmm_device_lock);
-		kfree(hmm_device);
-		return ERR_PTR(-EBUSY);
-	}
-	set_bit(hmm_device->minor, hmm_device_mask);
-	spin_unlock(&hmm_device_lock);
-
-	dev_set_name(&hmm_device->device, "hmm_device%d", hmm_device->minor);
-	hmm_device->device.devt = MKDEV(MAJOR(hmm_device_devt),
-					hmm_device->minor);
-	hmm_device->device.release = hmm_device_release;
-	dev_set_drvdata(&hmm_device->device, drvdata);
-	hmm_device->device.class = hmm_device_class;
-	device_initialize(&hmm_device->device);
-
-	return hmm_device;
-}
-EXPORT_SYMBOL(hmm_device_new);
-
-void hmm_device_put(struct hmm_device *hmm_device)
-{
-	put_device(&hmm_device->device);
-}
-EXPORT_SYMBOL(hmm_device_put);
-
-static int __init hmm_init(void)
-{
-	int ret;
-
-	ret = alloc_chrdev_region(&hmm_device_devt, 0,
-				  HMM_DEVICE_MAX,
-				  "hmm_device");
-	if (ret)
-		return ret;
-
-	hmm_device_class = class_create(THIS_MODULE, "hmm_device");
-	if (IS_ERR(hmm_device_class)) {
-		unregister_chrdev_region(hmm_device_devt, HMM_DEVICE_MAX);
-		return PTR_ERR(hmm_device_class);
-	}
-	return 0;
-}
-
-device_initcall(hmm_init);
 #endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */