linux/drivers/infiniband/ulp/ipoib/ipoib_vlan.c

/*
 * Copyright (c) 2004 Topspin Communications.  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.
 */

#include <linux/sched/signal.h>

#include <linux/init.h>
#include <linux/seq_file.h>

#include <linux/uaccess.h>

#include "ipoib.h"

static ssize_t parent_show(struct device *d, struct device_attribute *attr,
			   char *buf)
{ … }
static DEVICE_ATTR_RO(parent);

static bool is_child_unique(struct ipoib_dev_priv *ppriv,
			    struct ipoib_dev_priv *priv)
{ … }

/*
 * NOTE: If this function fails then the priv->dev will remain valid, however
 * priv will have been freed and must not be touched by caller in the error
 * case.
 *
 * If (ndev->reg_state == NETREG_UNINITIALIZED) then it is up to the caller to
 * free the net_device (just as rtnl_newlink does) otherwise the net_device
 * will be freed when the rtnl is unlocked.
 */
int __ipoib_vlan_add(struct ipoib_dev_priv *ppriv, struct ipoib_dev_priv *priv,
		     u16 pkey, int type)
{ … }

int ipoib_vlan_add(struct net_device *pdev, unsigned short pkey)
{ … }

struct ipoib_vlan_delete_work { … };

/*
 * sysfs callbacks of a netdevice cannot obtain the rtnl lock as
 * unregister_netdev ultimately deletes the sysfs files while holding the rtnl
 * lock. This deadlocks the system.
 *
 * A callback can use rtnl_trylock to avoid the deadlock but it cannot call
 * unregister_netdev as that internally takes and releases the rtnl_lock.  So
 * instead we find the netdev to unregister and then do the actual unregister
 * from the global work queue where we can obtain the rtnl_lock safely.
 */
static void ipoib_vlan_delete_task(struct work_struct *work)
{ … }

int ipoib_vlan_delete(struct net_device *pdev, unsigned short pkey)
{ … }