[mirror_ubuntu-bionic-kernel.git] / net / nfc / netlink.c

/*
 * Copyright (C) 2011 Instituto Nokia de Tecnologia
 *
 * Authors:
 *    Lauro Ramos Venancio <lauro.venancio@openbossa.org>
 *    Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the
 * Free Software Foundation, Inc.,
 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include <net/genetlink.h>
#include <linux/nfc.h>
#include <linux/slab.h>

#include "nfc.h"

static struct genl_multicast_group nfc_genl_event_mcgrp = {
	.name = NFC_GENL_MCAST_EVENT_NAME,
};

struct genl_family nfc_genl_family = {
	.id = GENL_ID_GENERATE,
	.hdrsize = 0,
	.name = NFC_GENL_NAME,
	.version = NFC_GENL_VERSION,
	.maxattr = NFC_ATTR_MAX,
};

static const struct nla_policy nfc_genl_policy[NFC_ATTR_MAX + 1] = {
	[NFC_ATTR_DEVICE_INDEX] = { .type = NLA_U32 },
	[NFC_ATTR_DEVICE_NAME] = { .type = NLA_STRING,
				.len = NFC_DEVICE_NAME_MAXSIZE },
	[NFC_ATTR_PROTOCOLS] = { .type = NLA_U32 },
};

static int nfc_genl_send_target(struct sk_buff *msg, struct nfc_target *target,
					struct netlink_callback *cb, int flags)
{
	void *hdr;

	nfc_dbg("entry");

	hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
				&nfc_genl_family, flags, NFC_CMD_GET_TARGET);
	if (!hdr)
		return -EMSGSIZE;

	genl_dump_check_consistent(cb, hdr, &nfc_genl_family);

	NLA_PUT_U32(msg, NFC_ATTR_TARGET_INDEX, target->idx);
	NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS,
				target->supported_protocols);
	NLA_PUT_U16(msg, NFC_ATTR_TARGET_SENS_RES, target->sens_res);
	NLA_PUT_U8(msg, NFC_ATTR_TARGET_SEL_RES, target->sel_res);

	return genlmsg_end(msg, hdr);

nla_put_failure:
	genlmsg_cancel(msg, hdr);
	return -EMSGSIZE;
}

static struct nfc_dev *__get_device_from_cb(struct netlink_callback *cb)
{
	struct nfc_dev *dev;
	int rc;
	u32 idx;

	rc = nlmsg_parse(cb->nlh, GENL_HDRLEN + nfc_genl_family.hdrsize,
						nfc_genl_family.attrbuf,
						nfc_genl_family.maxattr,
						nfc_genl_policy);
	if (rc < 0)
		return ERR_PTR(rc);

	if (!nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX])
		return ERR_PTR(-EINVAL);

	idx = nla_get_u32(nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX]);

	dev = nfc_get_device(idx);
	if (!dev)
		return ERR_PTR(-ENODEV);

	return dev;
}

static int nfc_genl_dump_targets(struct sk_buff *skb,
				struct netlink_callback *cb)
{
	int i = cb->args[0];
	struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];
	int rc;

	nfc_dbg("entry");

	if (!dev) {
		dev = __get_device_from_cb(cb);
		if (IS_ERR(dev))
			return PTR_ERR(dev);

		cb->args[1] = (long) dev;
	}

	spin_lock_bh(&dev->targets_lock);

	cb->seq = dev->targets_generation;

	while (i < dev->n_targets) {
		rc = nfc_genl_send_target(skb, &dev->targets[i], cb,
								NLM_F_MULTI);
		if (rc < 0)
			break;

		i++;
	}

	spin_unlock_bh(&dev->targets_lock);

	cb->args[0] = i;

	return skb->len;
}

static int nfc_genl_dump_targets_done(struct netlink_callback *cb)
{
	struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];

	nfc_dbg("entry");

	if (dev)
		nfc_put_device(dev);

	return 0;
}

int nfc_genl_targets_found(struct nfc_dev *dev)
{
	struct sk_buff *msg;
	void *hdr;

	nfc_dbg("entry");

	dev->genl_data.poll_req_pid = 0;

	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
	if (!msg)
		return -ENOMEM;

	hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
				NFC_EVENT_TARGETS_FOUND);
	if (!hdr)
		goto free_msg;

	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);

	genlmsg_end(msg, hdr);

	return genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_ATOMIC);

nla_put_failure:
	genlmsg_cancel(msg, hdr);
free_msg:
	nlmsg_free(msg);
	return -EMSGSIZE;
}

int nfc_genl_device_added(struct nfc_dev *dev)
{
	struct sk_buff *msg;
	void *hdr;

	nfc_dbg("entry");

	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
	if (!msg)
		return -ENOMEM;

	hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
				NFC_EVENT_DEVICE_ADDED);
	if (!hdr)
		goto free_msg;

	NLA_PUT_STRING(msg, NFC_ATTR_DEVICE_NAME, nfc_device_name(dev));
	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
	NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS, dev->supported_protocols);

	genlmsg_end(msg, hdr);

	genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL);

	return 0;

nla_put_failure:
	genlmsg_cancel(msg, hdr);
free_msg:
	nlmsg_free(msg);
	return -EMSGSIZE;
}

int nfc_genl_device_removed(struct nfc_dev *dev)
{
	struct sk_buff *msg;
	void *hdr;

	nfc_dbg("entry");

	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
	if (!msg)
		return -ENOMEM;

	hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
				NFC_EVENT_DEVICE_REMOVED);
	if (!hdr)
		goto free_msg;

	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);

	genlmsg_end(msg, hdr);

	genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL);

	return 0;

nla_put_failure:
	genlmsg_cancel(msg, hdr);
free_msg:
	nlmsg_free(msg);
	return -EMSGSIZE;
}

static int nfc_genl_send_device(struct sk_buff *msg, struct nfc_dev *dev,
						u32 pid, u32 seq,
						struct netlink_callback *cb,
						int flags)
{
	void *hdr;

	nfc_dbg("entry");

	hdr = genlmsg_put(msg, pid, seq, &nfc_genl_family, flags,
							NFC_CMD_GET_DEVICE);
	if (!hdr)
		return -EMSGSIZE;

	if (cb)
		genl_dump_check_consistent(cb, hdr, &nfc_genl_family);

	NLA_PUT_STRING(msg, NFC_ATTR_DEVICE_NAME, nfc_device_name(dev));
	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
	NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS, dev->supported_protocols);

	return genlmsg_end(msg, hdr);

nla_put_failure:
	genlmsg_cancel(msg, hdr);
	return -EMSGSIZE;
}

static int nfc_genl_dump_devices(struct sk_buff *skb,
				struct netlink_callback *cb)
{
	struct class_dev_iter *iter = (struct class_dev_iter *) cb->args[0];
	struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];
	bool first_call = false;

	nfc_dbg("entry");

	if (!iter) {
		first_call = true;
		iter = kmalloc(sizeof(struct class_dev_iter), GFP_KERNEL);
		if (!iter)
			return -ENOMEM;
		cb->args[0] = (long) iter;
	}

	mutex_lock(&nfc_devlist_mutex);

	cb->seq = nfc_devlist_generation;

	if (first_call) {
		nfc_device_iter_init(iter);
		dev = nfc_device_iter_next(iter);
	}

	while (dev) {
		int rc;

		rc = nfc_genl_send_device(skb, dev, NETLINK_CB(cb->skb).pid,
							cb->nlh->nlmsg_seq,
							cb, NLM_F_MULTI);
		if (rc < 0)
			break;

		dev = nfc_device_iter_next(iter);
	}

	mutex_unlock(&nfc_devlist_mutex);

	cb->args[1] = (long) dev;

	return skb->len;
}

static int nfc_genl_dump_devices_done(struct netlink_callback *cb)
{
	struct class_dev_iter *iter = (struct class_dev_iter *) cb->args[0];

	nfc_dbg("entry");

	nfc_device_iter_exit(iter);
	kfree(iter);

	return 0;
}

static int nfc_genl_get_device(struct sk_buff *skb, struct genl_info *info)
{
	struct sk_buff *msg;
	struct nfc_dev *dev;
	u32 idx;
	int rc = -ENOBUFS;

	nfc_dbg("entry");

	if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
		return -EINVAL;

	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);

	dev = nfc_get_device(idx);
	if (!dev)
		return -ENODEV;

	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
	if (!msg) {
		rc = -ENOMEM;
		goto out_putdev;
	}

	rc = nfc_genl_send_device(msg, dev, info->snd_pid, info->snd_seq,
								NULL, 0);
	if (rc < 0)
		goto out_free;

	nfc_put_device(dev);

	return genlmsg_reply(msg, info);

out_free:
	nlmsg_free(msg);
out_putdev:
	nfc_put_device(dev);
	return rc;
}

static int nfc_genl_start_poll(struct sk_buff *skb, struct genl_info *info)
{
	struct nfc_dev *dev;
	int rc;
	u32 idx;
	u32 protocols;

	nfc_dbg("entry");

	if (!info->attrs[NFC_ATTR_DEVICE_INDEX] ||
		!info->attrs[NFC_ATTR_PROTOCOLS])
		return -EINVAL;

	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
	protocols = nla_get_u32(info->attrs[NFC_ATTR_PROTOCOLS]);

	dev = nfc_get_device(idx);
	if (!dev)
		return -ENODEV;

	mutex_lock(&dev->genl_data.genl_data_mutex);

	rc = nfc_start_poll(dev, protocols);
	if (!rc)
		dev->genl_data.poll_req_pid = info->snd_pid;

	mutex_unlock(&dev->genl_data.genl_data_mutex);

	nfc_put_device(dev);
	return rc;
}

static int nfc_genl_stop_poll(struct sk_buff *skb, struct genl_info *info)
{
	struct nfc_dev *dev;
	int rc;
	u32 idx;

	nfc_dbg("entry");

	if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
		return -EINVAL;

	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);

	dev = nfc_get_device(idx);
	if (!dev)
		return -ENODEV;

	mutex_lock(&dev->genl_data.genl_data_mutex);

	if (dev->genl_data.poll_req_pid != info->snd_pid) {
		rc = -EBUSY;
		goto out;
	}

	rc = nfc_stop_poll(dev);
	dev->genl_data.poll_req_pid = 0;

out:
	mutex_unlock(&dev->genl_data.genl_data_mutex);
	nfc_put_device(dev);
	return rc;
}

static struct genl_ops nfc_genl_ops[] = {
	{
		.cmd = NFC_CMD_GET_DEVICE,
		.doit = nfc_genl_get_device,
		.dumpit = nfc_genl_dump_devices,
		.done = nfc_genl_dump_devices_done,
		.policy = nfc_genl_policy,
	},
	{
		.cmd = NFC_CMD_START_POLL,
		.doit = nfc_genl_start_poll,
		.policy = nfc_genl_policy,
	},
	{
		.cmd = NFC_CMD_STOP_POLL,
		.doit = nfc_genl_stop_poll,
		.policy = nfc_genl_policy,
	},
	{
		.cmd = NFC_CMD_GET_TARGET,
		.dumpit = nfc_genl_dump_targets,
		.done = nfc_genl_dump_targets_done,
		.policy = nfc_genl_policy,
	},
};

static int nfc_genl_rcv_nl_event(struct notifier_block *this,
						unsigned long event, void *ptr)
{
	struct netlink_notify *n = ptr;
	struct class_dev_iter iter;
	struct nfc_dev *dev;

	if (event != NETLINK_URELEASE || n->protocol != NETLINK_GENERIC)
		goto out;

	nfc_dbg("NETLINK_URELEASE event from id %d", n->pid);

	nfc_device_iter_init(&iter);
	dev = nfc_device_iter_next(&iter);

	while (dev) {
		mutex_lock(&dev->genl_data.genl_data_mutex);
		if (dev->genl_data.poll_req_pid == n->pid) {
			nfc_stop_poll(dev);
			dev->genl_data.poll_req_pid = 0;
		}
		mutex_unlock(&dev->genl_data.genl_data_mutex);
		dev = nfc_device_iter_next(&iter);
	}

	nfc_device_iter_exit(&iter);

out:
	return NOTIFY_DONE;
}

void nfc_genl_data_init(struct nfc_genl_data *genl_data)
{
	genl_data->poll_req_pid = 0;
	mutex_init(&genl_data->genl_data_mutex);
}

void nfc_genl_data_exit(struct nfc_genl_data *genl_data)
{
	mutex_destroy(&genl_data->genl_data_mutex);
}

static struct notifier_block nl_notifier = {
	.notifier_call  = nfc_genl_rcv_nl_event,
};

/**
 * nfc_genl_init() - Initialize netlink interface
 *
 * This initialization function registers the nfc netlink family.
 */
int __init nfc_genl_init(void)
{
	int rc;

	rc = genl_register_family_with_ops(&nfc_genl_family, nfc_genl_ops,
					ARRAY_SIZE(nfc_genl_ops));
	if (rc)
		return rc;

	rc = genl_register_mc_group(&nfc_genl_family, &nfc_genl_event_mcgrp);

	netlink_register_notifier(&nl_notifier);

	return rc;
}

/**
 * nfc_genl_exit() - Deinitialize netlink interface
 *
 * This exit function unregisters the nfc netlink family.
 */
void nfc_genl_exit(void)
{
	netlink_unregister_notifier(&nl_notifier);
	genl_unregister_family(&nfc_genl_family);
}
Commit	Line	Data
4d12b8b1 LRV	1	/*
	2	* Copyright (C) 2011 Instituto Nokia de Tecnologia
	3	*
	4	* Authors:
	5	* Lauro Ramos Venancio <lauro.venancio@openbossa.org>
	6	* Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2 of the License, or
	11	* (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the
	20	* Free Software Foundation, Inc.,
	21	* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	22	*/
	23
	24	#include <net/genetlink.h>
	25	#include <linux/nfc.h>
	26	#include <linux/slab.h>
	27
	28	#include "nfc.h"
	29
	30	static struct genl_multicast_group nfc_genl_event_mcgrp = {
	31	.name = NFC_GENL_MCAST_EVENT_NAME,
	32	};
	33
	34	struct genl_family nfc_genl_family = {
	35	.id = GENL_ID_GENERATE,
	36	.hdrsize = 0,
	37	.name = NFC_GENL_NAME,
	38	.version = NFC_GENL_VERSION,
	39	.maxattr = NFC_ATTR_MAX,
	40	};
	41
	42	static const struct nla_policy nfc_genl_policy[NFC_ATTR_MAX + 1] = {
	43	[NFC_ATTR_DEVICE_INDEX] = { .type = NLA_U32 },
	44	[NFC_ATTR_DEVICE_NAME] = { .type = NLA_STRING,
	45	.len = NFC_DEVICE_NAME_MAXSIZE },
	46	[NFC_ATTR_PROTOCOLS] = { .type = NLA_U32 },
	47	};
	48
	49	static int nfc_genl_send_target(struct sk_buff msg, struct nfc_target target,
	50	struct netlink_callback *cb, int flags)
	51	{
	52	void *hdr;
	53
	54	nfc_dbg("entry");
	55
	56	hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
	57	&nfc_genl_family, flags, NFC_CMD_GET_TARGET);
	58	if (!hdr)
	59	return -EMSGSIZE;
	60
	61	genl_dump_check_consistent(cb, hdr, &nfc_genl_family);
	62
	63	NLA_PUT_U32(msg, NFC_ATTR_TARGET_INDEX, target->idx);
	64	NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS,
65	target->supported_protocols);
66	NLA_PUT_U16(msg, NFC_ATTR_TARGET_SENS_RES, target->sens_res);
67	NLA_PUT_U8(msg, NFC_ATTR_TARGET_SEL_RES, target->sel_res);
68
69	return genlmsg_end(msg, hdr);
70
71	nla_put_failure:
72	genlmsg_cancel(msg, hdr);
73	return -EMSGSIZE;
74	}
75
76	static struct nfc_dev __get_device_from_cb(struct netlink_callback cb)
77	{
78	struct nfc_dev *dev;
79	int rc;
80	u32 idx;
81
82	rc = nlmsg_parse(cb->nlh, GENL_HDRLEN + nfc_genl_family.hdrsize,
83	nfc_genl_family.attrbuf,
84	nfc_genl_family.maxattr,
85	nfc_genl_policy);
86	if (rc < 0)
87	return ERR_PTR(rc);
88
89	if (!nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX])
90	return ERR_PTR(-EINVAL);
91
92	idx = nla_get_u32(nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX]);
93
94	dev = nfc_get_device(idx);
95	if (!dev)
96	return ERR_PTR(-ENODEV);
97
98	return dev;
99	}
100
101	static int nfc_genl_dump_targets(struct sk_buff *skb,
102	struct netlink_callback *cb)
103	{
104	int i = cb->args[0];
105	struct nfc_dev dev = (struct nfc_dev ) cb->args[1];
106	int rc;
107
108	nfc_dbg("entry");
109
110	if (!dev) {
111	dev = __get_device_from_cb(cb);
112	if (IS_ERR(dev))
113	return PTR_ERR(dev);
114
115	cb->args[1] = (long) dev;
116	}
117
118	spin_lock_bh(&dev->targets_lock);
119
120	cb->seq = dev->targets_generation;
121
122	while (i < dev->n_targets) {
123	rc = nfc_genl_send_target(skb, &dev->targets[i], cb,
124	NLM_F_MULTI);
125	if (rc < 0)
126	break;
127
128	i++;
129	}
130
131	spin_unlock_bh(&dev->targets_lock);
132
133	cb->args[0] = i;
134
135	return skb->len;
136	}
137
138	static int nfc_genl_dump_targets_done(struct netlink_callback *cb)
139	{
140	struct nfc_dev dev = (struct nfc_dev ) cb->args[1];
141
142	nfc_dbg("entry");
143
144	if (dev)
145	nfc_put_device(dev);
146
147	return 0;
148	}
149
150	int nfc_genl_targets_found(struct nfc_dev *dev)
151	{
152	struct sk_buff *msg;
153	void *hdr;
154
155	nfc_dbg("entry");
156
157	dev->genl_data.poll_req_pid = 0;
158
159	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
160	if (!msg)
161	return -ENOMEM;
162
163	hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
164	NFC_EVENT_TARGETS_FOUND);
165	if (!hdr)
166	goto free_msg;
167
168	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
169
170	genlmsg_end(msg, hdr);
171
172	return genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_ATOMIC);
173
174	nla_put_failure:
175	genlmsg_cancel(msg, hdr);
176	free_msg:
177	nlmsg_free(msg);
178	return -EMSGSIZE;
179	}
180
181	int nfc_genl_device_added(struct nfc_dev *dev)
182	{
183	struct sk_buff *msg;
184	void *hdr;
185
186	nfc_dbg("entry");
187
188	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
189	if (!msg)
190	return -ENOMEM;
191
192	hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
193	NFC_EVENT_DEVICE_ADDED);
194	if (!hdr)
195	goto free_msg;
196
197	NLA_PUT_STRING(msg, NFC_ATTR_DEVICE_NAME, nfc_device_name(dev));
198	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
199	NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS, dev->supported_protocols);
200
201	genlmsg_end(msg, hdr);
202
203	genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL);
204
205	return 0;
206
207	nla_put_failure:
208	genlmsg_cancel(msg, hdr);
209	free_msg:
210	nlmsg_free(msg);
211	return -EMSGSIZE;
212	}
213
214	int nfc_genl_device_removed(struct nfc_dev *dev)
215	{
216	struct sk_buff *msg;
217	void *hdr;
218
219	nfc_dbg("entry");
220
221	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
222	if (!msg)
223	return -ENOMEM;
224
225	hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
226	NFC_EVENT_DEVICE_REMOVED);
227	if (!hdr)
228	goto free_msg;
229
230	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
231
232	genlmsg_end(msg, hdr);
233
234	genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL);
235
236	return 0;
237
238	nla_put_failure:
239	genlmsg_cancel(msg, hdr);
240	free_msg:
241	nlmsg_free(msg);
242	return -EMSGSIZE;
243	}
244
245	static int nfc_genl_send_device(struct sk_buff msg, struct nfc_dev dev,
246	u32 pid, u32 seq,
247	struct netlink_callback *cb,
248	int flags)
249	{
250	void *hdr;
251
252	nfc_dbg("entry");
253
254	hdr = genlmsg_put(msg, pid, seq, &nfc_genl_family, flags,
255	NFC_CMD_GET_DEVICE);
256	if (!hdr)
257	return -EMSGSIZE;
258
259	if (cb)
260	genl_dump_check_consistent(cb, hdr, &nfc_genl_family);
261
262	NLA_PUT_STRING(msg, NFC_ATTR_DEVICE_NAME, nfc_device_name(dev));
263	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
264	NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS, dev->supported_protocols);
265
266	return genlmsg_end(msg, hdr);
267
268	nla_put_failure:
269	genlmsg_cancel(msg, hdr);
270	return -EMSGSIZE;
271	}
272
273	static int nfc_genl_dump_devices(struct sk_buff *skb,
274	struct netlink_callback *cb)
275	{
276	struct class_dev_iter iter = (struct class_dev_iter ) cb->args[0];
277	struct nfc_dev dev = (struct nfc_dev ) cb->args[1];
278	bool first_call = false;
279
280	nfc_dbg("entry");
281
282	if (!iter) {
283	first_call = true;
284	iter = kmalloc(sizeof(struct class_dev_iter), GFP_KERNEL);
285	if (!iter)
286	return -ENOMEM;
287	cb->args[0] = (long) iter;
288	}
289
290	mutex_lock(&nfc_devlist_mutex);
291
292	cb->seq = nfc_devlist_generation;
293
294	if (first_call) {
295	nfc_device_iter_init(iter);
296	dev = nfc_device_iter_next(iter);
297	}
298
299	while (dev) {
300	int rc;
301
302	rc = nfc_genl_send_device(skb, dev, NETLINK_CB(cb->skb).pid,
303	cb->nlh->nlmsg_seq,
304	cb, NLM_F_MULTI);
305	if (rc < 0)
306	break;
307
308	dev = nfc_device_iter_next(iter);
309	}
310
311	mutex_unlock(&nfc_devlist_mutex);
312
313	cb->args[1] = (long) dev;
314
315	return skb->len;
316	}
317
318	static int nfc_genl_dump_devices_done(struct netlink_callback *cb)
319	{
320	struct class_dev_iter iter = (struct class_dev_iter ) cb->args[0];
321
322	nfc_dbg("entry");
323
324	nfc_device_iter_exit(iter);
325	kfree(iter);
326
327	return 0;
328	}
329
330	static int nfc_genl_get_device(struct sk_buff skb, struct genl_info info)
331	{
332	struct sk_buff *msg;
333	struct nfc_dev *dev;
334	u32 idx;
335	int rc = -ENOBUFS;
336
337	nfc_dbg("entry");
338
339	if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
340	return -EINVAL;
341
342	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
343
344	dev = nfc_get_device(idx);
345	if (!dev)
346	return -ENODEV;
347
348	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
349	if (!msg) {
350	rc = -ENOMEM;
351	goto out_putdev;
352	}
353
354	rc = nfc_genl_send_device(msg, dev, info->snd_pid, info->snd_seq,
355	NULL, 0);
356	if (rc < 0)
357	goto out_free;
358
359	nfc_put_device(dev);
360
361	return genlmsg_reply(msg, info);
362
363	out_free:
364	nlmsg_free(msg);
365	out_putdev:
366	nfc_put_device(dev);
367	return rc;
368	}
369
370	static int nfc_genl_start_poll(struct sk_buff skb, struct genl_info info)
371	{
372	struct nfc_dev *dev;
373	int rc;
374	u32 idx;
375	u32 protocols;
376
377	nfc_dbg("entry");
378
379	if (!info->attrs[NFC_ATTR_DEVICE_INDEX] \|\|
380	!info->attrs[NFC_ATTR_PROTOCOLS])
381	return -EINVAL;
382
383	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
384	protocols = nla_get_u32(info->attrs[NFC_ATTR_PROTOCOLS]);
385
386	dev = nfc_get_device(idx);
387	if (!dev)
388	return -ENODEV;
389
390	mutex_lock(&dev->genl_data.genl_data_mutex);
391
392	rc = nfc_start_poll(dev, protocols);
393	if (!rc)
394	dev->genl_data.poll_req_pid = info->snd_pid;
395
396	mutex_unlock(&dev->genl_data.genl_data_mutex);
397
398	nfc_put_device(dev);
399	return rc;
400	}
401
402	static int nfc_genl_stop_poll(struct sk_buff skb, struct genl_info info)
403	{
404	struct nfc_dev *dev;
405	int rc;
406	u32 idx;
407
408	nfc_dbg("entry");
409
410	if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
411	return -EINVAL;
412
413	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
414
415	dev = nfc_get_device(idx);
416	if (!dev)
417	return -ENODEV;
418
419	mutex_lock(&dev->genl_data.genl_data_mutex);
420
421	if (dev->genl_data.poll_req_pid != info->snd_pid) {
422	rc = -EBUSY;
423	goto out;
424	}
425
426	rc = nfc_stop_poll(dev);
427	dev->genl_data.poll_req_pid = 0;
428
429	out:
430	mutex_unlock(&dev->genl_data.genl_data_mutex);
431	nfc_put_device(dev);
432	return rc;
433	}
434
435	static struct genl_ops nfc_genl_ops[] = {
436	{
437	.cmd = NFC_CMD_GET_DEVICE,
438	.doit = nfc_genl_get_device,
439	.dumpit = nfc_genl_dump_devices,
440	.done = nfc_genl_dump_devices_done,
441	.policy = nfc_genl_policy,
442	},
443	{
444	.cmd = NFC_CMD_START_POLL,
445	.doit = nfc_genl_start_poll,
446	.policy = nfc_genl_policy,
447	},
448	{
449	.cmd = NFC_CMD_STOP_POLL,
450	.doit = nfc_genl_stop_poll,
451	.policy = nfc_genl_policy,
452	},
453	{
454	.cmd = NFC_CMD_GET_TARGET,
455	.dumpit = nfc_genl_dump_targets,
456	.done = nfc_genl_dump_targets_done,
457	.policy = nfc_genl_policy,
458	},
459	};
460
461	static int nfc_genl_rcv_nl_event(struct notifier_block *this,
462	unsigned long event, void *ptr)
463	{
464	struct netlink_notify *n = ptr;
465	struct class_dev_iter iter;
466	struct nfc_dev *dev;
467
468	if (event != NETLINK_URELEASE \|\| n->protocol != NETLINK_GENERIC)
469	goto out;
470
471	nfc_dbg("NETLINK_URELEASE event from id %d", n->pid);
472
473	nfc_device_iter_init(&iter);
474	dev = nfc_device_iter_next(&iter);
475
476	while (dev) {
477	mutex_lock(&dev->genl_data.genl_data_mutex);
478	if (dev->genl_data.poll_req_pid == n->pid) {
479	nfc_stop_poll(dev);
480	dev->genl_data.poll_req_pid = 0;
481	}
482	mutex_unlock(&dev->genl_data.genl_data_mutex);
483	dev = nfc_device_iter_next(&iter);
484	}
485
486	nfc_device_iter_exit(&iter);
487
488	out:
489	return NOTIFY_DONE;
490	}
491
492	void nfc_genl_data_init(struct nfc_genl_data *genl_data)
493	{
494	genl_data->poll_req_pid = 0;
495	mutex_init(&genl_data->genl_data_mutex);
496	}
497
498	void nfc_genl_data_exit(struct nfc_genl_data *genl_data)
499	{
500	mutex_destroy(&genl_data->genl_data_mutex);
501	}
502
503	static struct notifier_block nl_notifier = {
504	.notifier_call = nfc_genl_rcv_nl_event,
505	};
506
507	/**
508	* nfc_genl_init() - Initialize netlink interface
509	*
510	* This initialization function registers the nfc netlink family.
511	*/
512	int __init nfc_genl_init(void)
513	{
514	int rc;
515
516	rc = genl_register_family_with_ops(&nfc_genl_family, nfc_genl_ops,
517	ARRAY_SIZE(nfc_genl_ops));
518	if (rc)
519	return rc;
520
521	rc = genl_register_mc_group(&nfc_genl_family, &nfc_genl_event_mcgrp);
522
523	netlink_register_notifier(&nl_notifier);
524
525	return rc;
526	}
527
528	/**
529	* nfc_genl_exit() - Deinitialize netlink interface
530	*
531	* This exit function unregisters the nfc netlink family.
532	*/
533	void nfc_genl_exit(void)
534	{
535	netlink_unregister_notifier(&nl_notifier);
536	genl_unregister_family(&nfc_genl_family);
537	}