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			goto found;
100		}
101	}
102	read_unlock_bh(&ctbl->lock);
103
104	write_lock_bh(&ctbl->lock);
105	if (!list_empty(&ctbl->ce_free_head)) {
106		ce = list_first_entry(&ctbl->ce_free_head,
107				      struct clip_entry, list);
108		list_del(&ce->list);
109		INIT_LIST_HEAD(&ce->list);
110		spin_lock_init(&ce->lock);
111		atomic_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				return ret;
122			}
123		} else {
124			ce->addr.sin_family = AF_INET;
125			memcpy((char *)(&ce->addr.sin_addr), lip,
126			       sizeof(struct in_addr));
127		}
128	} else {
129		write_unlock_bh(&ctbl->lock);
130		return -ENOMEM;
131	}
132	write_unlock_bh(&ctbl->lock);
133found:
134	atomic_inc(&ce->refcnt);
135
136	return 0;
137}
138EXPORT_SYMBOL(cxgb4_clip_get);
139
140void cxgb4_clip_release(const struct net_device *dev, const u32 *lip, u8 v6)
141{
142	struct adapter *adap = netdev2adap(dev);
143	struct clip_tbl *ctbl = adap->clipt;
144	struct clip_entry *ce, *cte;
145	u32 *addr = (u32 *)lip;
146	int hash;
147	int ret = -1;
148
149	hash = clip_addr_hash(ctbl, addr, v6);
150
151	read_lock_bh(&ctbl->lock);
152	list_for_each_entry(cte, &ctbl->hash_list[hash], list) {
153		if (cte->addr6.sin6_family == AF_INET6 && v6)
154			ret = memcmp(lip, cte->addr6.sin6_addr.s6_addr,
155				     sizeof(struct in6_addr));
156		else if (cte->addr.sin_family == AF_INET && !v6)
157			ret = memcmp(lip, (char *)(&cte->addr.sin_addr),
158				     sizeof(struct in_addr));
159		if (!ret) {
160			ce = cte;
161			read_unlock_bh(&ctbl->lock);
162			goto found;
163		}
164	}
165	read_unlock_bh(&ctbl->lock);
166
167	return;
168found:
169	write_lock_bh(&ctbl->lock);
170	spin_lock_bh(&ce->lock);
171	if (atomic_dec_and_test(&ce->refcnt)) {
172		list_del(&ce->list);
173		INIT_LIST_HEAD(&ce->list);
174		list_add_tail(&ce->list, &ctbl->ce_free_head);
175		atomic_inc(&ctbl->nfree);
176		if (v6)
177			clip6_release_mbox(dev, (const struct in6_addr *)lip);
178	}
179	spin_unlock_bh(&ce->lock);
180	write_unlock_bh(&ctbl->lock);
181}
182EXPORT_SYMBOL(cxgb4_clip_release);
183
184/* Retrieves IPv6 addresses from a root device (bond, vlan) associated with
185 * a physical device.
186 * The physical device reference is needed to send the actul CLIP command.
187 */
188static int cxgb4_update_dev_clip(struct net_device *root_dev,
189				 struct net_device *dev)
190{
191	struct inet6_dev *idev = NULL;
192	struct inet6_ifaddr *ifa;
193	int ret = 0;
194
195	idev = __in6_dev_get(root_dev);
196	if (!idev)
197		return ret;
198
199	read_lock_bh(&idev->lock);
200	list_for_each_entry(ifa, &idev->addr_list, if_list) {
201		ret = cxgb4_clip_get(dev, (const u32 *)ifa->addr.s6_addr, 1);
202		if (ret < 0)
203			break;
204	}
205	read_unlock_bh(&idev->lock);
206
207	return ret;
208}
209
210int cxgb4_update_root_dev_clip(struct net_device *dev)
211{
212	struct net_device *root_dev = NULL;
213	int i, ret = 0;
214
215	/* First populate the real net device's IPv6 addresses */
216	ret = cxgb4_update_dev_clip(dev, dev);
217	if (ret)
218		return ret;
219
220	/* Parse all bond and vlan devices layered on top of the physical dev */
221	root_dev = netdev_master_upper_dev_get_rcu(dev);
222	if (root_dev) {
223		ret = cxgb4_update_dev_clip(root_dev, dev);
224		if (ret)
225			return ret;
226	}
227
228	for (i = 0; i < VLAN_N_VID; i++) {
229		root_dev = __vlan_find_dev_deep_rcu(dev, htons(ETH_P_8021Q), i);
230		if (!root_dev)
231			continue;
232
233		ret = cxgb4_update_dev_clip(root_dev, dev);
234		if (ret)
235			break;
236	}
237
238	return ret;
239}
240EXPORT_SYMBOL(cxgb4_update_root_dev_clip);
241
242int clip_tbl_show(struct seq_file *seq, void *v)
243{
244	struct adapter *adapter = seq->private;
245	struct clip_tbl *ctbl = adapter->clipt;
246	struct clip_entry *ce;
247	char ip[60];
248	int i;
249
250	read_lock_bh(&ctbl->lock);
251
252	seq_puts(seq, "IP Address                  Users\n");
253	for (i = 0 ; i < ctbl->clipt_size;  ++i) {
254		list_for_each_entry(ce, &ctbl->hash_list[i], list) {
255			ip[0] = '\0';
256			sprintf(ip, "%pISc", &ce->addr);
257			seq_printf(seq, "%-25s   %u\n", ip,
258				   atomic_read(&ce->refcnt));
259		}
260	}
261	seq_printf(seq, "Free clip entries : %d\n", atomic_read(&ctbl->nfree));
262
263	read_unlock_bh(&ctbl->lock);
264
265	return 0;
266}
267
268struct clip_tbl *t4_init_clip_tbl(unsigned int clipt_start,
269				  unsigned int clipt_end)
270{
271	struct clip_entry *cl_list;
272	struct clip_tbl *ctbl;
273	unsigned int clipt_size;
274	int i;
275
276	if (clipt_start >= clipt_end)
277		return NULL;
278	clipt_size = clipt_end - clipt_start + 1;
279	if (clipt_size < CLIPT_MIN_HASH_BUCKETS)
280		return NULL;
281
282	ctbl = t4_alloc_mem(sizeof(*ctbl) +
283			    clipt_size*sizeof(struct list_head));
284	if (!ctbl)
285		return NULL;
286
287	ctbl->clipt_start = clipt_start;
288	ctbl->clipt_size = clipt_size;
289	INIT_LIST_HEAD(&ctbl->ce_free_head);
290
291	atomic_set(&ctbl->nfree, clipt_size);
292	rwlock_init(&ctbl->lock);
293
294	for (i = 0; i < ctbl->clipt_size; ++i)
295		INIT_LIST_HEAD(&ctbl->hash_list[i]);
296
297	cl_list = t4_alloc_mem(clipt_size*sizeof(struct clip_entry));
298	if (!cl_list) {
299		t4_free_mem(ctbl);
300		return NULL;
301	}
302	ctbl->cl_list = (void *)cl_list;
303
304	for (i = 0; i < clipt_size; i++) {
305		INIT_LIST_HEAD(&cl_list[i].list);
306		list_add_tail(&cl_list[i].list, &ctbl->ce_free_head);
307	}
308
309	return ctbl;
310}
311
312void t4_cleanup_clip_tbl(struct adapter *adap)
313{
314	struct clip_tbl *ctbl = adap->clipt;
315
316	if (ctbl) {
317		if (ctbl->cl_list)
318			t4_free_mem(ctbl->cl_list);
319		t4_free_mem(ctbl);
320	}
321}
322EXPORT_SYMBOL(t4_cleanup_clip_tbl);
323