1/*
2 *  This file is part of the Chelsio T4 Ethernet driver for Linux.
3 *  Copyright (C) 2003-2014 Chelsio Communications.  All rights reserved.
4 *
5 *  Written by Deepak (deepak.s@chelsio.com)
6 *
7 *  This program is distributed in the hope that it will be useful, but WITHOUT
8 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
9 *  FITNESS FOR A PARTICULAR PURPOSE.  See the LICENSE file included in this
10 *  release for licensing terms and conditions.
11 */
12
13#include <linux/module.h>
14#include <linux/netdevice.h>
15#include <linux/jhash.h>
16#include <linux/if_vlan.h>
17#include <net/addrconf.h>
18#include "cxgb4.h"
19#include "clip_tbl.h"
20
21static inline unsigned int ipv4_clip_hash(struct clip_tbl *c, const u32 *key)
22{
23	unsigned int clipt_size_half = c->clipt_size / 2;
24
25	return jhash_1word(*key, 0) % clipt_size_half;
26}
27
28static inline unsigned int ipv6_clip_hash(struct clip_tbl *d, const u32 *key)
29{
30	unsigned int clipt_size_half = d->clipt_size / 2;
31	u32 xor = key[0] ^ key[1] ^ key[2] ^ key[3];
32
33	return clipt_size_half +
34		(jhash_1word(xor, 0) % clipt_size_half);
35}
36
37static unsigned int clip_addr_hash(struct clip_tbl *ctbl, const u32 *addr,
38				   u8 v6)
39{
40	return v6 ? ipv6_clip_hash(ctbl, addr) :
41			ipv4_clip_hash(ctbl, addr);
42}
43
44static int clip6_get_mbox(const struct net_device *dev,
45			  const struct in6_addr *lip)
46{
47	struct adapter *adap = netdev2adap(dev);
48	struct fw_clip_cmd c;
49
50	memset(&c, 0, sizeof(c));
51	c.op_to_write = htonl(FW_CMD_OP_V(FW_CLIP_CMD) |
52			      FW_CMD_REQUEST_F | FW_CMD_WRITE_F);
53	c.alloc_to_len16 = htonl(FW_CLIP_CMD_ALLOC_F | FW_LEN16(c));
54	*(__be64 *)&c.ip_hi = *(__be64 *)(lip->s6_addr);
55	*(__be64 *)&c.ip_lo = *(__be64 *)(lip->s6_addr + 8);
56	return t4_wr_mbox_meat(adap, adap->mbox, &c, sizeof(c), &c, false);
57}
58
59static int clip6_release_mbox(const struct net_device *dev,
60			      const struct in6_addr *lip)
61{
62	struct adapter *adap = netdev2adap(dev);
63	struct fw_clip_cmd c;
64
65	memset(&c, 0, sizeof(c));
66	c.op_to_write = htonl(FW_CMD_OP_V(FW_CLIP_CMD) |
67			      FW_CMD_REQUEST_F | FW_CMD_READ_F);
68	c.alloc_to_len16 = htonl(FW_CLIP_CMD_FREE_F | FW_LEN16(c));
69	*(__be64 *)&c.ip_hi = *(__be64 *)(lip->s6_addr);
70	*(__be64 *)&c.ip_lo = *(__be64 *)(lip->s6_addr + 8);
71	return t4_wr_mbox_meat(adap, adap->mbox, &c, sizeof(c), &c, false);
72}
73
74int cxgb4_clip_get(const struct net_device *dev, const u32 *lip, u8 v6)
75{
76	struct adapter *adap = netdev2adap(dev);
77	struct clip_tbl *ctbl = adap->clipt;
78	struct clip_entry *ce, *cte;
79	u32 *addr = (u32 *)lip;
80	int hash;
81	int ret = -1;
82
83	if (!ctbl)
84		return 0;
85
86	hash = clip_addr_hash(ctbl, addr, v6);
87
88	read_lock_bh(&ctbl->lock);
89	list_for_each_entry(cte, &ctbl->hash_list[hash], list) {
90		if (cte->addr6.sin6_family == AF_INET6 && v6)
91			ret = memcmp(lip, cte->addr6.sin6_addr.s6_addr,
92				     sizeof(struct in6_addr));
93		else if (cte->addr.sin_family == AF_INET && !v6)
94			ret = memcmp(lip, (char *)(&cte->addr.sin_addr),
95				     sizeof(struct in_addr));
96		if (!ret) {
97			ce = cte;
98			read_unlock_bh(&ctbl->lock);
99			refcount_inc(&ce->refcnt);
100			return 0;
101		}
102	}
103	read_unlock_bh(&ctbl->lock);
104
105	write_lock_bh(&ctbl->lock);
106	if (!list_empty(&ctbl->ce_free_head)) {
107		ce = list_first_entry(&ctbl->ce_free_head,
108				      struct clip_entry, list);
109		list_del_init(&ce->list);
110		spin_lock_init(&ce->lock);
111		refcount_set(&ce->refcnt, 0);
112		atomic_dec(&ctbl->nfree);
113		list_add_tail(&ce->list, &ctbl->hash_list[hash]);
114		if (v6) {
115			ce->addr6.sin6_family = AF_INET6;
116			memcpy(ce->addr6.sin6_addr.s6_addr,
117			       lip, sizeof(struct in6_addr));
118			ret = clip6_get_mbox(dev, (const struct in6_addr *)lip);
119			if (ret) {
120				write_unlock_bh(&ctbl->lock);
121				dev_err(adap->pdev_dev,
122					"CLIP FW cmd failed with error %d, "
123					"Connections using %pI6c wont be "
124					"offloaded",
125					ret, ce->addr6.sin6_addr.s6_addr);
126				return ret;
127			}
128		} else {
129			ce->addr.sin_family = AF_INET;
130			memcpy((char *)(&ce->addr.sin_addr), lip,
131			       sizeof(struct in_addr));
132		}
133	} else {
134		write_unlock_bh(&ctbl->lock);
135		dev_info(adap->pdev_dev, "CLIP table overflow, "
136			 "Connections using %pI6c wont be offloaded",
137			 (void *)lip);
138		return -ENOMEM;
139	}
140	write_unlock_bh(&ctbl->lock);
141	refcount_set(&ce->refcnt, 1);
142	return 0;
143}
144EXPORT_SYMBOL(cxgb4_clip_get);
145
146void cxgb4_clip_release(const struct net_device *dev, const u32 *lip, u8 v6)
147{
148	struct adapter *adap = netdev2adap(dev);
149	struct clip_tbl *ctbl = adap->clipt;
150	struct clip_entry *ce, *cte;
151	u32 *addr = (u32 *)lip;
152	int hash;
153	int ret = -1;
154
155	if (!ctbl)
156		return;
157
158	hash = clip_addr_hash(ctbl, addr, v6);
159
160	read_lock_bh(&ctbl->lock);
161	list_for_each_entry(cte, &ctbl->hash_list[hash], list) {
162		if (cte->addr6.sin6_family == AF_INET6 && v6)
163			ret = memcmp(lip, cte->addr6.sin6_addr.s6_addr,
164				     sizeof(struct in6_addr));
165		else if (cte->addr.sin_family == AF_INET && !v6)
166			ret = memcmp(lip, (char *)(&cte->addr.sin_addr),
167				     sizeof(struct in_addr));
168		if (!ret) {
169			ce = cte;
170			read_unlock_bh(&ctbl->lock);
171			goto found;
172		}
173	}
174	read_unlock_bh(&ctbl->lock);
175
176	return;
177found:
178	write_lock_bh(&ctbl->lock);
179	spin_lock_bh(&ce->lock);
180	if (refcount_dec_and_test(&ce->refcnt)) {
181		list_del_init(&ce->list);
182		list_add_tail(&ce->list, &ctbl->ce_free_head);
183		atomic_inc(&ctbl->nfree);
184		if (v6)
185			clip6_release_mbox(dev, (const struct in6_addr *)lip);
186	}
187	spin_unlock_bh(&ce->lock);
188	write_unlock_bh(&ctbl->lock);
189}
190EXPORT_SYMBOL(cxgb4_clip_release);
191
192/* Retrieves IPv6 addresses from a root device (bond, vlan) associated with
193 * a physical device.
194 * The physical device reference is needed to send the actul CLIP command.
195 */
196static int cxgb4_update_dev_clip(struct net_device *root_dev,
197				 struct net_device *dev)
198{
199	struct inet6_dev *idev = NULL;
200	struct inet6_ifaddr *ifa;
201	int ret = 0;
202
203	idev = __in6_dev_get(root_dev);
204	if (!idev)
205		return ret;
206
207	read_lock_bh(&idev->lock);
208	list_for_each_entry(ifa, &idev->addr_list, if_list) {
209		ret = cxgb4_clip_get(dev, (const u32 *)ifa->addr.s6_addr, 1);
210		if (ret < 0)
211			break;
212	}
213	read_unlock_bh(&idev->lock);
214
215	return ret;
216}
217
218int cxgb4_update_root_dev_clip(struct net_device *dev)
219{
220	struct net_device *root_dev = NULL;
221	int i, ret = 0;
222
223	/* First populate the real net device's IPv6 addresses */
224	ret = cxgb4_update_dev_clip(dev, dev);
225	if (ret)
226		return ret;
227
228	/* Parse all bond and vlan devices layered on top of the physical dev */
229	root_dev = netdev_master_upper_dev_get_rcu(dev);
230	if (root_dev) {
231		ret = cxgb4_update_dev_clip(root_dev, dev);
232		if (ret)
233			return ret;
234	}
235
236	for (i = 0; i < VLAN_N_VID; i++) {
237		root_dev = __vlan_find_dev_deep_rcu(dev, htons(ETH_P_8021Q), i);
238		if (!root_dev)
239			continue;
240
241		ret = cxgb4_update_dev_clip(root_dev, dev);
242		if (ret)
243			break;
244	}
245
246	return ret;
247}
248EXPORT_SYMBOL(cxgb4_update_root_dev_clip);
249
250int clip_tbl_show(struct seq_file *seq, void *v)
251{
252	struct adapter *adapter = seq->private;
253	struct clip_tbl *ctbl = adapter->clipt;
254	struct clip_entry *ce;
255	char ip[60];
256	int i;
257
258	read_lock_bh(&ctbl->lock);
259
260	seq_puts(seq, "IP Address                  Users\n");
261	for (i = 0 ; i < ctbl->clipt_size;  ++i) {
262		list_for_each_entry(ce, &ctbl->hash_list[i], list) {
263			ip[0] = '\0';
264			sprintf(ip, "%pISc", &ce->addr);
265			seq_printf(seq, "%-25s   %u\n", ip,
266				   refcount_read(&ce->refcnt));
267		}
268	}
269	seq_printf(seq, "Free clip entries : %d\n", atomic_read(&ctbl->nfree));
270
271	read_unlock_bh(&ctbl->lock);
272
273	return 0;
274}
275
276struct clip_tbl *t4_init_clip_tbl(unsigned int clipt_start,
277				  unsigned int clipt_end)
278{
279	struct clip_entry *cl_list;
280	struct clip_tbl *ctbl;
281	unsigned int clipt_size;
282	int i;
283
284	if (clipt_start >= clipt_end)
285		return NULL;
286	clipt_size = clipt_end - clipt_start + 1;
287	if (clipt_size < CLIPT_MIN_HASH_BUCKETS)
288		return NULL;
289
290	ctbl = kvzalloc(struct_size(ctbl, hash_list, clipt_size), GFP_KERNEL);
291	if (!ctbl)
292		return NULL;
293
294	ctbl->clipt_start = clipt_start;
295	ctbl->clipt_size = clipt_size;
296	INIT_LIST_HEAD(&ctbl->ce_free_head);
297
298	atomic_set(&ctbl->nfree, clipt_size);
299	rwlock_init(&ctbl->lock);
300
301	for (i = 0; i < ctbl->clipt_size; ++i)
302		INIT_LIST_HEAD(&ctbl->hash_list[i]);
303
304	cl_list = kvcalloc(clipt_size, sizeof(struct clip_entry), GFP_KERNEL);
305	if (!cl_list) {
306		kvfree(ctbl);
307		return NULL;
308	}
309	ctbl->cl_list = (void *)cl_list;
310
311	for (i = 0; i < clipt_size; i++) {
312		INIT_LIST_HEAD(&cl_list[i].list);
313		list_add_tail(&cl_list[i].list, &ctbl->ce_free_head);
314	}
315
316	return ctbl;
317}
318
319void t4_cleanup_clip_tbl(struct adapter *adap)
320{
321	struct clip_tbl *ctbl = adap->clipt;
322
323	if (ctbl) {
324		kvfree(ctbl->cl_list);
325		kvfree(ctbl);
326	}
327}
328EXPORT_SYMBOL(t4_cleanup_clip_tbl);
329