Commit c5c4d92e authored by Parav Pandit's avatar Parav Pandit Committed by Jason Gunthorpe
Browse files

RDMA/uverbs: Use cdev_device_add() instead of cdev_add() 



Instead of doing two step process to add char device and create underlying
device, use cdev_device_add() which does both.

Currently a kobject per uverbs_device is created to keep reference to its
holding ib_uverbs_device in addition to its underlying device 'dev'.

Instead just use uverbs_device->dev to keep a reference to.

With this change there is single reference tracker for ib_uverbs_device
structure.

This allows for subsequent patch to registers group attribute as well
using single API cdev_device_add().

Signed-off-by: default avatarParav Pandit <parav@mellanox.com>
Reviewed-by: default avatarDaniel Jurgens <danielj@mellanox.com>
Signed-off-by: default avatarLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@mellanox.com>
parent adee9f3f

drivers/infiniband/core/uverbs.h

+1 −2
Original line number Diff line number Diff line
@@ -100,13 +100,12 @@ struct ib_uverbs_device { 
	atomic_t				refcount;

	int					num_comp_vectors;

	struct completion			comp;

	struct device			       *dev;

	struct device				dev;

	struct ib_device	__rcu	       *ib_dev;

	int					devnum;

	struct cdev			        cdev;

	struct rb_root				xrcd_tree;

	struct mutex				xrcd_tree_mutex;

	struct kobject				kobj;

	struct srcu_struct			disassociate_srcu;

	struct mutex				lists_mutex; /* protect lists */

	struct list_head			uverbs_file_list;

drivers/infiniband/core/uverbs_main.c

+29 −37
Original line number Diff line number Diff line
@@ -169,20 +169,16 @@ int uverbs_dealloc_mw(struct ib_mw *mw) 
	return ret;

}



static void ib_uverbs_release_dev(struct kobject *kobj)

static void ib_uverbs_release_dev(struct device *device)

{

	struct ib_uverbs_device *dev =

		container_of(kobj, struct ib_uverbs_device, kobj);

			container_of(device, struct ib_uverbs_device, dev);



	uverbs_destroy_api(dev->uapi);

	cleanup_srcu_struct(&dev->disassociate_srcu);

	kfree(dev);

}



static struct kobj_type ib_uverbs_dev_ktype = {

	.release = ib_uverbs_release_dev,

};



static void ib_uverbs_release_async_event_file(struct kref *ref)

{

	struct ib_uverbs_async_event_file *file =
@@ -265,7 +261,7 @@ void ib_uverbs_release_file(struct kref *ref) 
	if (atomic_dec_and_test(&file->device->refcount))

		ib_uverbs_comp_dev(file->device);



	kobject_put(&file->device->kobj);

	put_device(&file->device->dev);

	kfree(file);

}
@@ -838,6 +834,7 @@ static int ib_uverbs_open(struct inode *inode, struct file *filp) 
	if (!atomic_inc_not_zero(&dev->refcount))

		return -ENXIO;



	get_device(&dev->dev);

	srcu_key = srcu_read_lock(&dev->disassociate_srcu);

	mutex_lock(&dev->lists_mutex);

	ib_dev = srcu_dereference(dev->ib_dev,
@@ -877,7 +874,6 @@ static int ib_uverbs_open(struct inode *inode, struct file *filp) 
	init_rwsem(&file->hw_destroy_rwsem);



	filp->private_data = file;

	kobject_get(&dev->kobj);

	list_add_tail(&file->list, &dev->uverbs_file_list);

	mutex_unlock(&dev->lists_mutex);

	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
@@ -898,6 +894,7 @@ err: 
	if (atomic_dec_and_test(&dev->refcount))

		ib_uverbs_comp_dev(dev);



	put_device(&dev->dev);

	return ret;

}
@@ -953,14 +950,12 @@ static struct ib_client uverbs_client = { 
static ssize_t show_ibdev(struct device *device, struct device_attribute *attr,

			  char *buf)

{

	struct ib_uverbs_device *dev =

			container_of(device, struct ib_uverbs_device, dev);

	int ret = -ENODEV;

	int srcu_key;

	struct ib_uverbs_device *dev = dev_get_drvdata(device);

	struct ib_device *ib_dev;



	if (!dev)

		return -ENODEV;



	srcu_key = srcu_read_lock(&dev->disassociate_srcu);

	ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);

	if (ib_dev)
@@ -974,13 +969,12 @@ static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL); 
static ssize_t show_dev_abi_version(struct device *device,

				    struct device_attribute *attr, char *buf)

{

	struct ib_uverbs_device *dev = dev_get_drvdata(device);

	struct ib_uverbs_device *dev =

			container_of(device, struct ib_uverbs_device, dev);

	int ret = -ENODEV;

	int srcu_key;

	struct ib_device *ib_dev;



	if (!dev)

		return -ENODEV;

	srcu_key = srcu_read_lock(&dev->disassociate_srcu);

	ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);

	if (ib_dev)
@@ -1031,7 +1025,6 @@ static void ib_uverbs_add_one(struct ib_device *device) 
	init_completion(&uverbs_dev->comp);

	uverbs_dev->xrcd_tree = RB_ROOT;

	mutex_init(&uverbs_dev->xrcd_tree_mutex);

	kobject_init(&uverbs_dev->kobj, &ib_uverbs_dev_ktype);

	mutex_init(&uverbs_dev->lists_mutex);

	INIT_LIST_HEAD(&uverbs_dev->uverbs_file_list);

	INIT_LIST_HEAD(&uverbs_dev->uverbs_events_file_list);
@@ -1052,40 +1045,41 @@ static void ib_uverbs_add_one(struct ib_device *device) 
	if (ib_uverbs_create_uapi(device, uverbs_dev))

		goto err_uapi;



	cdev_init(&uverbs_dev->cdev, NULL);

	device_initialize(&uverbs_dev->dev);

	uverbs_dev->dev.class = uverbs_class;

	uverbs_dev->dev.parent = device->dev.parent;

	uverbs_dev->dev.devt = base;

	uverbs_dev->dev.release = ib_uverbs_release_dev;

	dev_set_name(&uverbs_dev->dev, "uverbs%d", uverbs_dev->devnum);



	cdev_init(&uverbs_dev->cdev,

		  device->mmap ? &uverbs_mmap_fops : &uverbs_fops);

	uverbs_dev->cdev.owner = THIS_MODULE;

	uverbs_dev->cdev.ops = device->mmap ? &uverbs_mmap_fops : &uverbs_fops;

	cdev_set_parent(&uverbs_dev->cdev, &uverbs_dev->kobj);

	kobject_set_name(&uverbs_dev->cdev.kobj, "uverbs%d", uverbs_dev->devnum);

	if (cdev_add(&uverbs_dev->cdev, base, 1))

		goto err_cdev;



	uverbs_dev->dev = device_create(uverbs_class, device->dev.parent,

					uverbs_dev->cdev.dev, uverbs_dev,

					"uverbs%d", uverbs_dev->devnum);

	if (IS_ERR(uverbs_dev->dev))

	ret = cdev_device_add(&uverbs_dev->cdev, &uverbs_dev->dev);

	if (ret)

		goto err_cdev;



	if (device_create_file(uverbs_dev->dev, &dev_attr_ibdev))

		goto err_class;

	if (device_create_file(uverbs_dev->dev, &dev_attr_abi_version))

		goto err_class;

	if (device_create_file(&uverbs_dev->dev, &dev_attr_ibdev))

		goto err_file;

	if (device_create_file(&uverbs_dev->dev, &dev_attr_abi_version))

		goto err_file;



	ib_set_client_data(device, &uverbs_client, uverbs_dev);



	return;



err_class:

	device_destroy(uverbs_class, uverbs_dev->cdev.dev);

err_file:

	cdev_device_del(&uverbs_dev->cdev, &uverbs_dev->dev);

err_cdev:

	cdev_del(&uverbs_dev->cdev);

	put_device(&uverbs_dev->dev);

err_uapi:

	clear_bit(devnum, dev_map);

err:

	if (atomic_dec_and_test(&uverbs_dev->refcount))

		ib_uverbs_comp_dev(uverbs_dev);

	wait_for_completion(&uverbs_dev->comp);

	kobject_put(&uverbs_dev->kobj);

	return;

}
@@ -1155,9 +1149,7 @@ static void ib_uverbs_remove_one(struct ib_device *device, void *client_data) 
	if (!uverbs_dev)

		return;



	dev_set_drvdata(uverbs_dev->dev, NULL);

	device_destroy(uverbs_class, uverbs_dev->cdev.dev);

	cdev_del(&uverbs_dev->cdev);

	cdev_device_del(&uverbs_dev->cdev, &uverbs_dev->dev);

	clear_bit(uverbs_dev->devnum, dev_map);



	if (device->disassociate_ucontext) {
@@ -1181,7 +1173,7 @@ static void ib_uverbs_remove_one(struct ib_device *device, void *client_data) 
	if (wait_clients)

		wait_for_completion(&uverbs_dev->comp);



	kobject_put(&uverbs_dev->kobj);

	put_device(&uverbs_dev->dev);

}



static char *uverbs_devnode(struct device *dev, umode_t *mode)

CRA Git | Maintained and supported by SUSTech CRA and CCSE