[linux-2.6-block.git] / 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/module.h>
#include <linux/sched/signal.h>

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

#include <linux/uaccess.h>

#include "ipoib.h"

static ssize_t show_parent(struct device *d, struct device_attribute *attr,
			   char *buf)
{
	struct net_device *dev = to_net_dev(d);
	struct ipoib_dev_priv *priv = ipoib_priv(dev);

	return sprintf(buf, "%s\n", priv->parent->name);
}
static DEVICE_ATTR(parent, S_IRUGO, show_parent, NULL);

/*
 * NOTE: If this function fails then the priv->dev will remain valid, however
 * priv can 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)
{
	struct net_device *ndev = priv->dev;
	int result;

	ASSERT_RTNL();

	priv->parent = ppriv->dev;
	priv->pkey = pkey;
	priv->child_type = type;

	/* We do not need to touch priv if register_netdevice fails */
	ndev->priv_destructor = ipoib_intf_free;

	result = register_netdevice(ndev);
	if (result) {
		ipoib_warn(priv, "failed to initialize; error %i", result);

		/*
		 * register_netdevice sometimes calls priv_destructor,
		 * sometimes not. Make sure it was done.
		 */
		if (ndev->priv_destructor)
			ndev->priv_destructor(ndev);
		return result;
	}

	/* RTNL childs don't need proprietary sysfs entries */
	if (type == IPOIB_LEGACY_CHILD) {
		if (ipoib_cm_add_mode_attr(ndev))
			goto sysfs_failed;
		if (ipoib_add_pkey_attr(ndev))
			goto sysfs_failed;
		if (ipoib_add_umcast_attr(ndev))
			goto sysfs_failed;

		if (device_create_file(&ndev->dev, &dev_attr_parent))
			goto sysfs_failed;
	}

	list_add_tail(&priv->list, &ppriv->child_intfs);

	return 0;

sysfs_failed:
	unregister_netdevice(priv->dev);
	return -ENOMEM;
}

int ipoib_vlan_add(struct net_device *pdev, unsigned short pkey)
{
	struct ipoib_dev_priv *ppriv, *priv;
	char intf_name[IFNAMSIZ];
	struct net_device *ndev;
	struct ipoib_dev_priv *tpriv;
	int result;

	if (!capable(CAP_NET_ADMIN))
		return -EPERM;

	ppriv = ipoib_priv(pdev);

	snprintf(intf_name, sizeof(intf_name), "%s.%04x",
		 ppriv->dev->name, pkey);

	if (!rtnl_trylock())
		return restart_syscall();

	if (pdev->reg_state != NETREG_REGISTERED) {
		rtnl_unlock();
		return -EPERM;
	}

	if (!down_write_trylock(&ppriv->vlan_rwsem)) {
		rtnl_unlock();
		return restart_syscall();
	}

	/*
	 * First ensure this isn't a duplicate. We check the parent device and
	 * then all of the legacy child interfaces to make sure the Pkey
	 * doesn't match.
	 */
	if (ppriv->pkey == pkey) {
		result = -ENOTUNIQ;
		goto out;
	}

	list_for_each_entry(tpriv, &ppriv->child_intfs, list) {
		if (tpriv->pkey == pkey &&
		    tpriv->child_type == IPOIB_LEGACY_CHILD) {
			result = -ENOTUNIQ;
			goto out;
		}
	}

	priv = ipoib_intf_alloc(ppriv->ca, ppriv->port, intf_name);
	if (!priv) {
		result = -ENOMEM;
		goto out;
	}
	ndev = priv->dev;

	result = __ipoib_vlan_add(ppriv, priv, pkey, IPOIB_LEGACY_CHILD);

	if (result && ndev->reg_state == NETREG_UNINITIALIZED)
		free_netdev(ndev);

out:
	up_write(&ppriv->vlan_rwsem);
	rtnl_unlock();

	return result;
}

struct ipoib_vlan_delete_work {
	struct work_struct work;
	struct net_device *dev;
};

/*
 * 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)
{
	struct ipoib_vlan_delete_work *pwork =
		container_of(work, struct ipoib_vlan_delete_work, work);
	struct net_device *dev = pwork->dev;

	rtnl_lock();

	/* Unregistering tasks can race with another task or parent removal */
	if (dev->reg_state == NETREG_REGISTERED) {
		struct ipoib_dev_priv *priv = ipoib_priv(dev);
		struct ipoib_dev_priv *ppriv = ipoib_priv(priv->parent);

		down_write(&ppriv->vlan_rwsem);
		list_del(&priv->list);
		up_write(&ppriv->vlan_rwsem);

		ipoib_dbg(ppriv, "delete child vlan %s\n", dev->name);
		unregister_netdevice(dev);
	}

	rtnl_unlock();

	kfree(pwork);
}

int ipoib_vlan_delete(struct net_device *pdev, unsigned short pkey)
{
	struct ipoib_dev_priv *ppriv, *priv, *tpriv;
	int rc;

	if (!capable(CAP_NET_ADMIN))
		return -EPERM;

	if (!rtnl_trylock())
		return restart_syscall();

	if (pdev->reg_state != NETREG_REGISTERED) {
		rtnl_unlock();
		return -EPERM;
	}

	ppriv = ipoib_priv(pdev);

	rc = -ENODEV;
	list_for_each_entry_safe(priv, tpriv, &ppriv->child_intfs, list) {
		if (priv->pkey == pkey &&
		    priv->child_type == IPOIB_LEGACY_CHILD) {
			struct ipoib_vlan_delete_work *work;

			work = kmalloc(sizeof(*work), GFP_KERNEL);
			if (!work) {
				rc = -ENOMEM;
				goto out;
			}

			down_write(&ppriv->vlan_rwsem);
			list_del_init(&priv->list);
			up_write(&ppriv->vlan_rwsem);
			work->dev = priv->dev;
			INIT_WORK(&work->work, ipoib_vlan_delete_task);
			queue_work(ipoib_workqueue, &work->work);

			rc = 0;
			break;
		}
	}

out:
	rtnl_unlock();

	return rc;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright (c) 2004 Topspin Communications. All rights reserved.
	3	*
	4	* This software is available to you under a choice of one of two
	5	* licenses. You may choose to be licensed under the terms of the GNU
	6	* General Public License (GPL) Version 2, available from the file
	7	* COPYING in the main directory of this source tree, or the
	8	* OpenIB.org BSD license below:
	9	*
	10	* Redistribution and use in source and binary forms, with or
	11	* without modification, are permitted provided that the following
	12	* conditions are met:
	13	*
	14	* - Redistributions of source code must retain the above
	15	* copyright notice, this list of conditions and the following
	16	* disclaimer.
	17	*
	18	* - Redistributions in binary form must reproduce the above
	19	* copyright notice, this list of conditions and the following
	20	* disclaimer in the documentation and/or other materials
	21	* provided with the distribution.
	22	*
	23	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	24	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	25	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	26	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	27	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	28	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	29	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	30	* SOFTWARE.
1da177e4 LT	31	*/
1da177e4 LT	32
1da177e4	33	#include <linux/module.h>
174cd4b1	34	#include <linux/sched/signal.h>
1da177e4 LT	35
1da177e4 LT	36	#include <linux/init.h>
1da177e4 LT	37	#include <linux/seq_file.h>
1da177e4 LT	38
7c0f6ba6	39	#include <linux/uaccess.h>
1da177e4 LT	40
	41	#include "ipoib.h"
	42
43cb76d9 GKH	43	static ssize_t show_parent(struct device d, struct device_attribute attr,
43cb76d9 GKH	44	char *buf)
1da177e4	45	{
43cb76d9	46	struct net_device *dev = to_net_dev(d);
c1048aff	47	struct ipoib_dev_priv *priv = ipoib_priv(dev);
1da177e4 LT	48
	49	return sprintf(buf, "%s\n", priv->parent->name);
	50	}
43cb76d9	51	static DEVICE_ATTR(parent, S_IRUGO, show_parent, NULL);
1da177e4	52
9f49a5b5 JG	53	/*
	54	* NOTE: If this function fails then the priv->dev will remain valid, however
	55	* priv can have been freed and must not be touched by caller in the error
	56	* case.
	57	*
	58	* If (ndev->reg_state == NETREG_UNINITIALIZED) then it is up to the caller to
	59	* free the net_device (just as rtnl_newlink does) otherwise the net_device
	60	* will be freed when the rtnl is unlocked.
	61	*/
9baa0b03 OG	62	int __ipoib_vlan_add(struct ipoib_dev_priv ppriv, struct ipoib_dev_priv priv,
9baa0b03 OG	63	u16 pkey, int type)
1da177e4	64	{
9f49a5b5	65	struct net_device *ndev = priv->dev;
1da177e4 LT	66	int result;
1da177e4 LT	67
9f49a5b5 JG	68	ASSERT_RTNL();
9f49a5b5 JG	69
2c153959	70	priv->parent = ppriv->dev;
1da177e4	71	priv->pkey = pkey;
eaeb3984	72	priv->child_type = type;
1da177e4	73
9f49a5b5 JG	74	/* We do not need to touch priv if register_netdevice fails */
	75	ndev->priv_destructor = ipoib_intf_free;
	76
	77	result = register_netdevice(ndev);
1da177e4 LT	78	if (result) {
1da177e4 LT	79	ipoib_warn(priv, "failed to initialize; error %i", result);
9f49a5b5 JG	80
	81	/*
	82	* register_netdevice sometimes calls priv_destructor,
	83	* sometimes not. Make sure it was done.
	84	*/
	85	if (ndev->priv_destructor)
	86	ndev->priv_destructor(ndev);
eaeb3984	87	return result;
1da177e4 LT	88	}
1da177e4 LT	89
862096a8 OG	90	/* RTNL childs don't need proprietary sysfs entries */
862096a8 OG	91	if (type == IPOIB_LEGACY_CHILD) {
9f49a5b5	92	if (ipoib_cm_add_mode_attr(ndev))
862096a8	93	goto sysfs_failed;
9f49a5b5	94	if (ipoib_add_pkey_attr(ndev))
862096a8	95	goto sysfs_failed;
9f49a5b5	96	if (ipoib_add_umcast_attr(ndev))
862096a8 OG	97	goto sysfs_failed;
862096a8 OG	98
9f49a5b5	99	if (device_create_file(&ndev->dev, &dev_attr_parent))
862096a8 OG	100	goto sysfs_failed;
862096a8 OG	101	}
1da177e4 LT	102
	103	list_add_tail(&priv->list, &ppriv->child_intfs);
	104
1da177e4 LT	105	return 0;
	106
	107	sysfs_failed:
cbbe1efa	108	unregister_netdevice(priv->dev);
eaeb3984	109	return -ENOMEM;
9baa0b03 OG	110	}
	111
	112	int ipoib_vlan_add(struct net_device *pdev, unsigned short pkey)
	113	{
	114	struct ipoib_dev_priv ppriv, priv;
	115	char intf_name[IFNAMSIZ];
9f49a5b5	116	struct net_device *ndev;
9baa0b03 OG	117	struct ipoib_dev_priv *tpriv;
	118	int result;
	119
	120	if (!capable(CAP_NET_ADMIN))
	121	return -EPERM;
	122
cd565b4b	123	ppriv = ipoib_priv(pdev);
9baa0b03	124
b1b63970	125	snprintf(intf_name, sizeof(intf_name), "%s.%04x",
9baa0b03	126	ppriv->dev->name, pkey);
cd565b4b	127
ee190ab7	128	if (!rtnl_trylock())
4542d66b FD	129	return restart_syscall();
4542d66b FD	130
577e07ff JG	131	if (pdev->reg_state != NETREG_REGISTERED) {
577e07ff JG	132	rtnl_unlock();
577e07ff JG	133	return -EPERM;
	134	}
	135
9c6f42e9	136	if (!down_write_trylock(&ppriv->vlan_rwsem)) {
69956d83	137	rtnl_unlock();
9c6f42e9	138	return restart_syscall();
69956d83	139	}
9baa0b03	140
9baa0b03 OG	141	/*
	142	* First ensure this isn't a duplicate. We check the parent device and
	143	* then all of the legacy child interfaces to make sure the Pkey
	144	* doesn't match.
	145	*/
	146	if (ppriv->pkey == pkey) {
	147	result = -ENOTUNIQ;
	148	goto out;
	149	}
	150
	151	list_for_each_entry(tpriv, &ppriv->child_intfs, list) {
	152	if (tpriv->pkey == pkey &&
	153	tpriv->child_type == IPOIB_LEGACY_CHILD) {
	154	result = -ENOTUNIQ;
	155	goto out;
	156	}
	157	}
	158
9f49a5b5 JG	159	priv = ipoib_intf_alloc(ppriv->ca, ppriv->port, intf_name);
	160	if (!priv) {
	161	result = -ENOMEM;
	162	goto out;
	163	}
	164	ndev = priv->dev;
	165
9baa0b03 OG	166	result = __ipoib_vlan_add(ppriv, priv, pkey, IPOIB_LEGACY_CHILD);
9baa0b03 OG	167
9f49a5b5 JG	168	if (result && ndev->reg_state == NETREG_UNINITIALIZED)
	169	free_netdev(ndev);
	170
9baa0b03	171	out:
f47944cc	172	up_write(&ppriv->vlan_rwsem);
89a3987a FD	173	rtnl_unlock();
89a3987a FD	174
1da177e4 LT	175	return result;
	176	}
	177
ee190ab7 JG	178	struct ipoib_vlan_delete_work {
	179	struct work_struct work;
	180	struct net_device *dev;
	181	};
	182
	183	/*
	184	* sysfs callbacks of a netdevice cannot obtain the rtnl lock as
	185	* unregister_netdev ultimately deletes the sysfs files while holding the rtnl
	186	* lock. This deadlocks the system.
	187	*
	188	* A callback can use rtnl_trylock to avoid the deadlock but it cannot call
	189	* unregister_netdev as that internally takes and releases the rtnl_lock. So
	190	* instead we find the netdev to unregister and then do the actual unregister
	191	* from the global work queue where we can obtain the rtnl_lock safely.
	192	*/
	193	static void ipoib_vlan_delete_task(struct work_struct *work)
	194	{
	195	struct ipoib_vlan_delete_work *pwork =
	196	container_of(work, struct ipoib_vlan_delete_work, work);
	197	struct net_device *dev = pwork->dev;
	198
	199	rtnl_lock();
	200
	201	/* Unregistering tasks can race with another task or parent removal */
	202	if (dev->reg_state == NETREG_REGISTERED) {
	203	struct ipoib_dev_priv *priv = ipoib_priv(dev);
	204	struct ipoib_dev_priv *ppriv = ipoib_priv(priv->parent);
	205
	206	down_write(&ppriv->vlan_rwsem);
	207	list_del(&priv->list);
	208	up_write(&ppriv->vlan_rwsem);
	209
	210	ipoib_dbg(ppriv, "delete child vlan %s\n", dev->name);
	211	unregister_netdevice(dev);
	212	}
	213
	214	rtnl_unlock();
	215
	216	kfree(pwork);
	217	}
	218
1da177e4 LT	219	int ipoib_vlan_delete(struct net_device *pdev, unsigned short pkey)
	220	{
	221	struct ipoib_dev_priv ppriv, priv, *tpriv;
ee190ab7	222	int rc;
1da177e4 LT	223
	224	if (!capable(CAP_NET_ADMIN))
	225	return -EPERM;
	226
ee190ab7	227	if (!rtnl_trylock())
69956d83 ES	228	return restart_syscall();
69956d83 ES	229
577e07ff JG	230	if (pdev->reg_state != NETREG_REGISTERED) {
577e07ff JG	231	rtnl_unlock();
577e07ff JG	232	return -EPERM;
	233	}
	234
ee190ab7	235	ppriv = ipoib_priv(pdev);
9c6f42e9	236
ee190ab7	237	rc = -ENODEV;
1da177e4	238	list_for_each_entry_safe(priv, tpriv, &ppriv->child_intfs, list) {
9baa0b03 OG	239	if (priv->pkey == pkey &&
9baa0b03 OG	240	priv->child_type == IPOIB_LEGACY_CHILD) {
ee190ab7 JG	241	struct ipoib_vlan_delete_work *work;
	242
	243	work = kmalloc(sizeof(*work), GFP_KERNEL);
	244	if (!work) {
	245	rc = -ENOMEM;
	246	goto out;
	247	}
	248
	249	down_write(&ppriv->vlan_rwsem);
	250	list_del_init(&priv->list);
	251	up_write(&ppriv->vlan_rwsem);
	252	work->dev = priv->dev;
	253	INIT_WORK(&work->work, ipoib_vlan_delete_task);
	254	queue_work(ipoib_workqueue, &work->work);
	255
	256	rc = 0;
1da177e4 LT	257	break;
	258	}
	259	}
1c3098cd	260
ee190ab7	261	out:
cbbe1efa	262	rtnl_unlock();
1da177e4	263
ee190ab7	264	return rc;
1da177e4	265	}