[PATCH] IB uverbs: core implementation

/*

 * Copyright (c) 2005 Topspin Communications.  All rights reserved.

 * Copyright (c) 2005 Cisco Systems.  All rights reserved.

 *

 * This software is available to you under a choice of one of two

 * licenses.  You may choose to be licensed under the terms of the GNU

 * General Public License (GPL) Version 2, available from the file

 * COPYING in the main directory of this source tree, or the

 * OpenIB.org BSD license below:

 *

 *     Redistribution and use in source and binary forms, with or

 *     without modification, are permitted provided that the following

 *     conditions are met:

 *

 *      - Redistributions of source code must retain the above

 *        copyright notice, this list of conditions and the following

 *        disclaimer.

 *

 *      - Redistributions in binary form must reproduce the above

 *        copyright notice, this list of conditions and the following

 *        disclaimer in the documentation and/or other materials

 *        provided with the distribution.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS

 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN

 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN

 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE

 * SOFTWARE.

 *

 * $Id: uverbs.h 2559 2005-06-06 19:43:16Z roland $

 */

#ifndef UVERBS_H

#define UVERBS_H

/* Include device.h and fs.h until cdev.h is self-sufficient */

#include <linux/fs.h>

#include <linux/device.h>

#include <linux/cdev.h>

#include <linux/kref.h>

#include <linux/idr.h>

#include <ib_verbs.h>

#include <ib_user_verbs.h>

struct ib_uverbs_device {

	int					devnum;

	struct cdev				dev;

	struct class_device			class_dev;

	struct ib_device		       *ib_dev;

	int					num_comp;

};

struct ib_uverbs_event_file {

	struct kref				ref;

	struct ib_uverbs_file		       *uverbs_file;

	spinlock_t				lock;

	int					fd;

	int					is_async;

	wait_queue_head_t			poll_wait;

	struct list_head			event_list;

};

struct ib_uverbs_file {

	struct kref				ref;

	struct ib_uverbs_device		       *device;

	struct ib_ucontext		       *ucontext;

	struct ib_event_handler			event_handler;

	struct ib_uverbs_event_file	        async_file;

	struct ib_uverbs_event_file	        comp_file[1];

};

struct ib_uverbs_async_event {

	struct ib_uverbs_async_event_desc	desc;

	struct list_head			list;

};

struct ib_uverbs_comp_event {

	struct ib_uverbs_comp_event_desc	desc;

	struct list_head			list;

};

struct ib_uobject_mr {

	struct ib_uobject			uobj;

	struct page			       *page_list;

	struct scatterlist		       *sg_list;

};

extern struct semaphore ib_uverbs_idr_mutex;

extern struct idr ib_uverbs_pd_idr;

extern struct idr ib_uverbs_mr_idr;

extern struct idr ib_uverbs_mw_idr;

extern struct idr ib_uverbs_ah_idr;

extern struct idr ib_uverbs_cq_idr;

extern struct idr ib_uverbs_qp_idr;

void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context);

void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr);

void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr);

int ib_umem_get(struct ib_device *dev, struct ib_umem *mem,

		void *addr, size_t size, int write);

void ib_umem_release(struct ib_device *dev, struct ib_umem *umem);

void ib_umem_release_on_close(struct ib_device *dev, struct ib_umem *umem);

#define IB_UVERBS_DECLARE_CMD(name)					\

	ssize_t ib_uverbs_##name(struct ib_uverbs_file *file,		\

				 const char __user *buf, int in_len,	\

				 int out_len)

IB_UVERBS_DECLARE_CMD(query_params);

IB_UVERBS_DECLARE_CMD(get_context);

IB_UVERBS_DECLARE_CMD(query_device);

IB_UVERBS_DECLARE_CMD(query_port);

IB_UVERBS_DECLARE_CMD(query_gid);

IB_UVERBS_DECLARE_CMD(query_pkey);

IB_UVERBS_DECLARE_CMD(alloc_pd);

IB_UVERBS_DECLARE_CMD(dealloc_pd);

IB_UVERBS_DECLARE_CMD(reg_mr);

IB_UVERBS_DECLARE_CMD(dereg_mr);

IB_UVERBS_DECLARE_CMD(create_cq);

IB_UVERBS_DECLARE_CMD(destroy_cq);

IB_UVERBS_DECLARE_CMD(create_qp);

IB_UVERBS_DECLARE_CMD(modify_qp);

IB_UVERBS_DECLARE_CMD(destroy_qp);

IB_UVERBS_DECLARE_CMD(attach_mcast);

IB_UVERBS_DECLARE_CMD(detach_mcast);

#endif /* UVERBS_H */

/*

 * Copyright (c) 2005 Topspin Communications.  All rights reserved.

 * Copyright (c) 2005 Cisco Systems.  All rights reserved.

 *

 * This software is available to you under a choice of one of two

 * licenses.  You may choose to be licensed under the terms of the GNU

 * General Public License (GPL) Version 2, available from the file

 * COPYING in the main directory of this source tree, or the

 * OpenIB.org BSD license below:

 *

 *     Redistribution and use in source and binary forms, with or

 *     without modification, are permitted provided that the following

 *     conditions are met:

 *

 *      - Redistributions of source code must retain the above

 *        copyright notice, this list of conditions and the following

 *        disclaimer.

 *

 *      - Redistributions in binary form must reproduce the above

 *        copyright notice, this list of conditions and the following

 *        disclaimer in the documentation and/or other materials

 *        provided with the distribution.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS

 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN

 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN

 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE

 * SOFTWARE.

 *

 * $Id: uverbs_main.c 2733 2005-06-28 19:14:34Z roland $

 */

#include <linux/module.h>

#include <linux/init.h>

#include <linux/device.h>

#include <linux/err.h>

#include <linux/fs.h>

#include <linux/poll.h>

#include <linux/file.h>

#include <linux/mount.h>

#include <asm/uaccess.h>

#include "uverbs.h"

MODULE_AUTHOR("Roland Dreier");

MODULE_DESCRIPTION("InfiniBand userspace verbs access");

MODULE_LICENSE("Dual BSD/GPL");

#define INFINIBANDEVENTFS_MAGIC	0x49426576	/* "IBev" */

enum {

	IB_UVERBS_MAJOR       = 231,

	IB_UVERBS_BASE_MINOR  = 192,

	IB_UVERBS_MAX_DEVICES = 32

};

#define IB_UVERBS_BASE_DEV	MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR)

DECLARE_MUTEX(ib_uverbs_idr_mutex);

DEFINE_IDR(ib_uverbs_pd_idr);

DEFINE_IDR(ib_uverbs_mr_idr);

DEFINE_IDR(ib_uverbs_mw_idr);

DEFINE_IDR(ib_uverbs_ah_idr);

DEFINE_IDR(ib_uverbs_cq_idr);

DEFINE_IDR(ib_uverbs_qp_idr);

static spinlock_t map_lock;

static DECLARE_BITMAP(dev_map, IB_UVERBS_MAX_DEVICES);

static ssize_t (*uverbs_cmd_table[])(struct ib_uverbs_file *file,

				     const char __user *buf, int in_len,

				     int out_len) = {

	[IB_USER_VERBS_CMD_QUERY_PARAMS]  = ib_uverbs_query_params,

	[IB_USER_VERBS_CMD_GET_CONTEXT]   = ib_uverbs_get_context,

	[IB_USER_VERBS_CMD_QUERY_DEVICE]  = ib_uverbs_query_device,

	[IB_USER_VERBS_CMD_QUERY_PORT]    = ib_uverbs_query_port,

	[IB_USER_VERBS_CMD_QUERY_GID]     = ib_uverbs_query_gid,

	[IB_USER_VERBS_CMD_QUERY_PKEY]    = ib_uverbs_query_pkey,

	[IB_USER_VERBS_CMD_ALLOC_PD]      = ib_uverbs_alloc_pd,

	[IB_USER_VERBS_CMD_DEALLOC_PD]    = ib_uverbs_dealloc_pd,

	[IB_USER_VERBS_CMD_REG_MR]        = ib_uverbs_reg_mr,

	[IB_USER_VERBS_CMD_DEREG_MR]      = ib_uverbs_dereg_mr,

	[IB_USER_VERBS_CMD_CREATE_CQ]     = ib_uverbs_create_cq,

	[IB_USER_VERBS_CMD_DESTROY_CQ]    = ib_uverbs_destroy_cq,

	[IB_USER_VERBS_CMD_CREATE_QP]     = ib_uverbs_create_qp,

	[IB_USER_VERBS_CMD_MODIFY_QP]     = ib_uverbs_modify_qp,

	[IB_USER_VERBS_CMD_DESTROY_QP]    = ib_uverbs_destroy_qp,

	[IB_USER_VERBS_CMD_ATTACH_MCAST]  = ib_uverbs_attach_mcast,

	[IB_USER_VERBS_CMD_DETACH_MCAST]  = ib_uverbs_detach_mcast,

};

static struct vfsmount *uverbs_event_mnt;

static void ib_uverbs_add_one(struct ib_device *device);

static void ib_uverbs_remove_one(struct ib_device *device);

static int ib_dealloc_ucontext(struct ib_ucontext *context)

{

	struct ib_uobject *uobj, *tmp;

	if (!context)

		return 0;

	down(&ib_uverbs_idr_mutex);

	/* XXX Free AHs */

	list_for_each_entry_safe(uobj, tmp, &context->qp_list, list) {

		struct ib_qp *qp = idr_find(&ib_uverbs_qp_idr, uobj->id);

		idr_remove(&ib_uverbs_qp_idr, uobj->id);

		ib_destroy_qp(qp);

		list_del(&uobj->list);

		kfree(uobj);

	}

	list_for_each_entry_safe(uobj, tmp, &context->cq_list, list) {

		struct ib_cq *cq = idr_find(&ib_uverbs_cq_idr, uobj->id);

		idr_remove(&ib_uverbs_cq_idr, uobj->id);

		ib_destroy_cq(cq);

		list_del(&uobj->list);

		kfree(uobj);

	}

	/* XXX Free SRQs */

	/* XXX Free MWs */

	list_for_each_entry_safe(uobj, tmp, &context->mr_list, list) {

		struct ib_mr *mr = idr_find(&ib_uverbs_mr_idr, uobj->id);

		struct ib_umem_object *memobj;

		idr_remove(&ib_uverbs_mr_idr, uobj->id);

		ib_dereg_mr(mr);

		memobj = container_of(uobj, struct ib_umem_object, uobject);

		ib_umem_release_on_close(mr->device, &memobj->umem);

		list_del(&uobj->list);

		kfree(memobj);

	}

	list_for_each_entry_safe(uobj, tmp, &context->pd_list, list) {

		struct ib_pd *pd = idr_find(&ib_uverbs_pd_idr, uobj->id);

		idr_remove(&ib_uverbs_pd_idr, uobj->id);

		ib_dealloc_pd(pd);

		list_del(&uobj->list);

		kfree(uobj);

	}

	up(&ib_uverbs_idr_mutex);

	return context->device->dealloc_ucontext(context);

}

static void ib_uverbs_release_file(struct kref *ref)

{

	struct ib_uverbs_file *file =

		container_of(ref, struct ib_uverbs_file, ref);

	module_put(file->device->ib_dev->owner);

	kfree(file);

}

static ssize_t ib_uverbs_event_read(struct file *filp, char __user *buf,

				    size_t count, loff_t *pos)

{

	struct ib_uverbs_event_file *file = filp->private_data;

	void *event;

	int eventsz;

	int ret = 0;

	spin_lock_irq(&file->lock);

	while (list_empty(&file->event_list) && file->fd >= 0) {

		spin_unlock_irq(&file->lock);

		if (filp->f_flags & O_NONBLOCK)

			return -EAGAIN;

		if (wait_event_interruptible(file->poll_wait,

					     !list_empty(&file->event_list) ||

					     file->fd < 0))

			return -ERESTARTSYS;

		spin_lock_irq(&file->lock);

	}

	if (file->fd < 0) {

		spin_unlock_irq(&file->lock);

		return -ENODEV;

	}

	if (file->is_async) {

		event   = list_entry(file->event_list.next,

				     struct ib_uverbs_async_event, list);

		eventsz = sizeof (struct ib_uverbs_async_event_desc);

	} else {

		event   = list_entry(file->event_list.next,

				     struct ib_uverbs_comp_event, list);

		eventsz = sizeof (struct ib_uverbs_comp_event_desc);

	}

	if (eventsz > count) {

		ret   = -EINVAL;

		event = NULL;

	} else

		list_del(file->event_list.next);

	spin_unlock_irq(&file->lock);

	if (event) {

		if (copy_to_user(buf, event, eventsz))

			ret = -EFAULT;

		else

			ret = eventsz;

	}

	kfree(event);

	return ret;

}

static unsigned int ib_uverbs_event_poll(struct file *filp,

					 struct poll_table_struct *wait)

{

	unsigned int pollflags = 0;

	struct ib_uverbs_event_file *file = filp->private_data;

	poll_wait(filp, &file->poll_wait, wait);

	spin_lock_irq(&file->lock);

	if (file->fd < 0)

		pollflags = POLLERR;

	else if (!list_empty(&file->event_list))

		pollflags = POLLIN | POLLRDNORM;

	spin_unlock_irq(&file->lock);

	return pollflags;

}

static void ib_uverbs_event_release(struct ib_uverbs_event_file *file)

{

	struct list_head *entry, *tmp;

	spin_lock_irq(&file->lock);

	if (file->fd != -1) {

		file->fd = -1;

		list_for_each_safe(entry, tmp, &file->event_list)

			if (file->is_async)

				kfree(list_entry(entry, struct ib_uverbs_async_event, list));

			else

				kfree(list_entry(entry, struct ib_uverbs_comp_event, list));

	}

	spin_unlock_irq(&file->lock);

}

static int ib_uverbs_event_close(struct inode *inode, struct file *filp)

{

	struct ib_uverbs_event_file *file = filp->private_data;

	ib_uverbs_event_release(file);

	kref_put(&file->uverbs_file->ref, ib_uverbs_release_file);

	return 0;

}

static struct file_operations uverbs_event_fops = {

	/*

	 * No .owner field since we artificially create event files,

	 * so there is no increment to the module reference count in

	 * the open path.  All event files come from a uverbs command

	 * file, which already takes a module reference, so this is OK.

	 */

	.read 	 = ib_uverbs_event_read,

	.poll    = ib_uverbs_event_poll,

	.release = ib_uverbs_event_close

};

void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context)

{

	struct ib_uverbs_file       *file = cq_context;

	struct ib_uverbs_comp_event *entry;

	unsigned long                flags;

	entry = kmalloc(sizeof *entry, GFP_ATOMIC);

	if (!entry)

		return;

	entry->desc.cq_handle = cq->uobject->user_handle;

	spin_lock_irqsave(&file->comp_file[0].lock, flags);

	list_add_tail(&entry->list, &file->comp_file[0].event_list);

	spin_unlock_irqrestore(&file->comp_file[0].lock, flags);

	wake_up_interruptible(&file->comp_file[0].poll_wait);

}

static void ib_uverbs_async_handler(struct ib_uverbs_file *file,

				    __u64 element, __u64 event)

{

	struct ib_uverbs_async_event *entry;

	unsigned long flags;

	entry = kmalloc(sizeof *entry, GFP_ATOMIC);

	if (!entry)

		return;

	entry->desc.element    = element;

	entry->desc.event_type = event;

	spin_lock_irqsave(&file->async_file.lock, flags);

	list_add_tail(&entry->list, &file->async_file.event_list);

	spin_unlock_irqrestore(&file->async_file.lock, flags);

	wake_up_interruptible(&file->async_file.poll_wait);

}

void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)

{

	ib_uverbs_async_handler(context_ptr,

				event->element.cq->uobject->user_handle,

				event->event);

}

void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)

{

	ib_uverbs_async_handler(context_ptr,

				event->element.qp->uobject->user_handle,

				event->event);

}

static void ib_uverbs_event_handler(struct ib_event_handler *handler,

				    struct ib_event *event)

{

	struct ib_uverbs_file *file =

		container_of(handler, struct ib_uverbs_file, event_handler);

	ib_uverbs_async_handler(file, event->element.port_num, event->event);

}

static int ib_uverbs_event_init(struct ib_uverbs_event_file *file,

				struct ib_uverbs_file *uverbs_file)

{

	struct file *filp;

	spin_lock_init(&file->lock);

	INIT_LIST_HEAD(&file->event_list);

	init_waitqueue_head(&file->poll_wait);

	file->uverbs_file = uverbs_file;

	file->fd = get_unused_fd();

	if (file->fd < 0)

		return file->fd;

	filp = get_empty_filp();

	if (!filp) {

		put_unused_fd(file->fd);

		return -ENFILE;

	}

	filp->f_op 	   = &uverbs_event_fops;

	filp->f_vfsmnt 	   = mntget(uverbs_event_mnt);

	filp->f_dentry 	   = dget(uverbs_event_mnt->mnt_root);

	filp->f_mapping    = filp->f_dentry->d_inode->i_mapping;

	filp->f_flags      = O_RDONLY;

	filp->f_mode       = FMODE_READ;

	filp->private_data = file;

	fd_install(file->fd, filp);

	return 0;

}

static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,

			     size_t count, loff_t *pos)

{

	struct ib_uverbs_file *file = filp->private_data;

	struct ib_uverbs_cmd_hdr hdr;

	if (count < sizeof hdr)

		return -EINVAL;

	if (copy_from_user(&hdr, buf, sizeof hdr))

		return -EFAULT;

	if (hdr.in_words * 4 != count)

		return -EINVAL;

	if (hdr.command < 0 || hdr.command >= ARRAY_SIZE(uverbs_cmd_table))

		return -EINVAL;

	if (!file->ucontext                               &&

	    hdr.command != IB_USER_VERBS_CMD_QUERY_PARAMS &&

	    hdr.command != IB_USER_VERBS_CMD_GET_CONTEXT)

		return -EINVAL;

	return uverbs_cmd_table[hdr.command](file, buf + sizeof hdr,

					     hdr.in_words * 4, hdr.out_words * 4);

}

static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma)

{

	struct ib_uverbs_file *file = filp->private_data;

	if (!file->ucontext)

		return -ENODEV;

	else

		return file->device->ib_dev->mmap(file->ucontext, vma);

}

static int ib_uverbs_open(struct inode *inode, struct file *filp)

{

	struct ib_uverbs_device *dev =

		container_of(inode->i_cdev, struct ib_uverbs_device, dev);

	struct ib_uverbs_file *file;

	int i = 0;

	int ret;

	if (!try_module_get(dev->ib_dev->owner))

		return -ENODEV;

	file = kmalloc(sizeof *file +

		       (dev->num_comp - 1) * sizeof (struct ib_uverbs_event_file),

		       GFP_KERNEL);

	if (!file)

		return -ENOMEM;

	file->device = dev;

	kref_init(&file->ref);

	file->ucontext = NULL;

	ret = ib_uverbs_event_init(&file->async_file, file);

	if (ret)

		goto err;

	file->async_file.is_async = 1;

	kref_get(&file->ref);

	for (i = 0; i < dev->num_comp; ++i) {

		ret = ib_uverbs_event_init(&file->comp_file[i], file);

		if (ret)

			goto err_async;

		kref_get(&file->ref);

		file->comp_file[i].is_async = 0;

	}

	filp->private_data = file;

	INIT_IB_EVENT_HANDLER(&file->event_handler, dev->ib_dev,

			      ib_uverbs_event_handler);

	if (ib_register_event_handler(&file->event_handler))

		goto err_async;

	return 0;

err_async:

	while (i--)

		ib_uverbs_event_release(&file->comp_file[i]);

	ib_uverbs_event_release(&file->async_file);

err:

	kref_put(&file->ref, ib_uverbs_release_file);

	return ret;

}

static int ib_uverbs_close(struct inode *inode, struct file *filp)

{

	struct ib_uverbs_file *file = filp->private_data;

	int i;

	ib_unregister_event_handler(&file->event_handler);

	ib_uverbs_event_release(&file->async_file);

	ib_dealloc_ucontext(file->ucontext);

	for (i = 0; i < file->device->num_comp; ++i)

		ib_uverbs_event_release(&file->comp_file[i]);

	kref_put(&file->ref, ib_uverbs_release_file);

	return 0;

}

static struct file_operations uverbs_fops = {

	.owner 	 = THIS_MODULE,

	.write 	 = ib_uverbs_write,

	.open 	 = ib_uverbs_open,

	.release = ib_uverbs_close

};

static struct file_operations uverbs_mmap_fops = {

	.owner 	 = THIS_MODULE,

	.write 	 = ib_uverbs_write,

	.mmap    = ib_uverbs_mmap,

	.open 	 = ib_uverbs_open,

	.release = ib_uverbs_close

};

static struct ib_client uverbs_client = {

	.name   = "uverbs",

	.add    = ib_uverbs_add_one,

	.remove = ib_uverbs_remove_one

};

static ssize_t show_ibdev(struct class_device *class_dev, char *buf)

{

	struct ib_uverbs_device *dev =

		container_of(class_dev, struct ib_uverbs_device, class_dev);

	return sprintf(buf, "%s\n", dev->ib_dev->name);

}

static CLASS_DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);

static void ib_uverbs_release_class_dev(struct class_device *class_dev)

{

	struct ib_uverbs_device *dev =

		container_of(class_dev, struct ib_uverbs_device, class_dev);

	cdev_del(&dev->dev);

	clear_bit(dev->devnum, dev_map);

	kfree(dev);

}

static struct class uverbs_class = {

	.name    = "infiniband_verbs",

	.release = ib_uverbs_release_class_dev

};

static ssize_t show_abi_version(struct class *class, char *buf)

{

	return sprintf(buf, "%d\n", IB_USER_VERBS_ABI_VERSION);

}

static CLASS_ATTR(abi_version, S_IRUGO, show_abi_version, NULL);

static void ib_uverbs_add_one(struct ib_device *device)

{

	struct ib_uverbs_device *uverbs_dev;

	if (!device->alloc_ucontext)

		return;

	uverbs_dev = kmalloc(sizeof *uverbs_dev, GFP_KERNEL);

	if (!uverbs_dev)

		return;

	memset(uverbs_dev, 0, sizeof *uverbs_dev);

	spin_lock(&map_lock);

	uverbs_dev->devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES);

	if (uverbs_dev->devnum >= IB_UVERBS_MAX_DEVICES) {

		spin_unlock(&map_lock);

		goto err;

	}

	set_bit(uverbs_dev->devnum, dev_map);

	spin_unlock(&map_lock);

	uverbs_dev->ib_dev   = device;

	uverbs_dev->num_comp = 1;

	if (device->mmap)

		cdev_init(&uverbs_dev->dev, &uverbs_mmap_fops);

	else