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 
21 static 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 
28 static 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 
37 static 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 
44 static 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 
59 static 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 
74 int 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(&ce->list);
110 		INIT_LIST_HEAD(&ce->list);
111 		spin_lock_init(&ce->lock);
112 		refcount_set(&ce->refcnt, 0);
113 		atomic_dec(&ctbl->nfree);
114 		list_add_tail(&ce->list, &ctbl->hash_list[hash]);
115 		if (v6) {
116 			ce->addr6.sin6_family = AF_INET6;
117 			memcpy(ce->addr6.sin6_addr.s6_addr,
118 			       lip, sizeof(struct in6_addr));
119 			ret = clip6_get_mbox(dev, (const struct in6_addr *)lip);
120 			if (ret) {
121 				write_unlock_bh(&ctbl->lock);
122 				dev_err(adap->pdev_dev,
123 					"CLIP FW cmd failed with error %d, "
124 					"Connections using %pI6c wont be "
125 					"offloaded",
126 					ret, ce->addr6.sin6_addr.s6_addr);
127 				return ret;
128 			}
129 		} else {
130 			ce->addr.sin_family = AF_INET;
131 			memcpy((char *)(&ce->addr.sin_addr), lip,
132 			       sizeof(struct in_addr));
133 		}
134 	} else {
135 		write_unlock_bh(&ctbl->lock);
136 		dev_info(adap->pdev_dev, "CLIP table overflow, "
137 			 "Connections using %pI6c wont be offloaded",
138 			 (void *)lip);
139 		return -ENOMEM;
140 	}
141 	write_unlock_bh(&ctbl->lock);
142 	refcount_set(&ce->refcnt, 1);
143 	return 0;
144 }
145 EXPORT_SYMBOL(cxgb4_clip_get);
146 
147 void cxgb4_clip_release(const struct net_device *dev, const u32 *lip, u8 v6)
148 {
149 	struct adapter *adap = netdev2adap(dev);
150 	struct clip_tbl *ctbl = adap->clipt;
151 	struct clip_entry *ce, *cte;
152 	u32 *addr = (u32 *)lip;
153 	int hash;
154 	int ret = -1;
155 
156 	if (!ctbl)
157 		return;
158 
159 	hash = clip_addr_hash(ctbl, addr, v6);
160 
161 	read_lock_bh(&ctbl->lock);
162 	list_for_each_entry(cte, &ctbl->hash_list[hash], list) {
163 		if (cte->addr6.sin6_family == AF_INET6 && v6)
164 			ret = memcmp(lip, cte->addr6.sin6_addr.s6_addr,
165 				     sizeof(struct in6_addr));
166 		else if (cte->addr.sin_family == AF_INET && !v6)
167 			ret = memcmp(lip, (char *)(&cte->addr.sin_addr),
168 				     sizeof(struct in_addr));
169 		if (!ret) {
170 			ce = cte;
171 			read_unlock_bh(&ctbl->lock);
172 			goto found;
173 		}
174 	}
175 	read_unlock_bh(&ctbl->lock);
176 
177 	return;
178 found:
179 	write_lock_bh(&ctbl->lock);
180 	spin_lock_bh(&ce->lock);
181 	if (refcount_dec_and_test(&ce->refcnt)) {
182 		list_del(&ce->list);
183 		INIT_LIST_HEAD(&ce->list);
184 		list_add_tail(&ce->list, &ctbl->ce_free_head);
185 		atomic_inc(&ctbl->nfree);
186 		if (v6)
187 			clip6_release_mbox(dev, (const struct in6_addr *)lip);
188 	}
189 	spin_unlock_bh(&ce->lock);
190 	write_unlock_bh(&ctbl->lock);
191 }
192 EXPORT_SYMBOL(cxgb4_clip_release);
193 
194 /* Retrieves IPv6 addresses from a root device (bond, vlan) associated with
195  * a physical device.
196  * The physical device reference is needed to send the actul CLIP command.
197  */
198 static int cxgb4_update_dev_clip(struct net_device *root_dev,
199 				 struct net_device *dev)
200 {
201 	struct inet6_dev *idev = NULL;
202 	struct inet6_ifaddr *ifa;
203 	int ret = 0;
204 
205 	idev = __in6_dev_get(root_dev);
206 	if (!idev)
207 		return ret;
208 
209 	read_lock_bh(&idev->lock);
210 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
211 		ret = cxgb4_clip_get(dev, (const u32 *)ifa->addr.s6_addr, 1);
212 		if (ret < 0)
213 			break;
214 	}
215 	read_unlock_bh(&idev->lock);
216 
217 	return ret;
218 }
219 
220 int cxgb4_update_root_dev_clip(struct net_device *dev)
221 {
222 	struct net_device *root_dev = NULL;
223 	int i, ret = 0;
224 
225 	/* First populate the real net device's IPv6 addresses */
226 	ret = cxgb4_update_dev_clip(dev, dev);
227 	if (ret)
228 		return ret;
229 
230 	/* Parse all bond and vlan devices layered on top of the physical dev */
231 	root_dev = netdev_master_upper_dev_get_rcu(dev);
232 	if (root_dev) {
233 		ret = cxgb4_update_dev_clip(root_dev, dev);
234 		if (ret)
235 			return ret;
236 	}
237 
238 	for (i = 0; i < VLAN_N_VID; i++) {
239 		root_dev = __vlan_find_dev_deep_rcu(dev, htons(ETH_P_8021Q), i);
240 		if (!root_dev)
241 			continue;
242 
243 		ret = cxgb4_update_dev_clip(root_dev, dev);
244 		if (ret)
245 			break;
246 	}
247 
248 	return ret;
249 }
250 EXPORT_SYMBOL(cxgb4_update_root_dev_clip);
251 
252 int clip_tbl_show(struct seq_file *seq, void *v)
253 {
254 	struct adapter *adapter = seq->private;
255 	struct clip_tbl *ctbl = adapter->clipt;
256 	struct clip_entry *ce;
257 	char ip[60];
258 	int i;
259 
260 	read_lock_bh(&ctbl->lock);
261 
262 	seq_puts(seq, "IP Address                  Users\n");
263 	for (i = 0 ; i < ctbl->clipt_size;  ++i) {
264 		list_for_each_entry(ce, &ctbl->hash_list[i], list) {
265 			ip[0] = '\0';
266 			sprintf(ip, "%pISc", &ce->addr);
267 			seq_printf(seq, "%-25s   %u\n", ip,
268 				   refcount_read(&ce->refcnt));
269 		}
270 	}
271 	seq_printf(seq, "Free clip entries : %d\n", atomic_read(&ctbl->nfree));
272 
273 	read_unlock_bh(&ctbl->lock);
274 
275 	return 0;
276 }
277 
278 struct clip_tbl *t4_init_clip_tbl(unsigned int clipt_start,
279 				  unsigned int clipt_end)
280 {
281 	struct clip_entry *cl_list;
282 	struct clip_tbl *ctbl;
283 	unsigned int clipt_size;
284 	int i;
285 
286 	if (clipt_start >= clipt_end)
287 		return NULL;
288 	clipt_size = clipt_end - clipt_start + 1;
289 	if (clipt_size < CLIPT_MIN_HASH_BUCKETS)
290 		return NULL;
291 
292 	ctbl = kvzalloc(sizeof(*ctbl) +
293 			    clipt_size*sizeof(struct list_head), GFP_KERNEL);
294 	if (!ctbl)
295 		return NULL;
296 
297 	ctbl->clipt_start = clipt_start;
298 	ctbl->clipt_size = clipt_size;
299 	INIT_LIST_HEAD(&ctbl->ce_free_head);
300 
301 	atomic_set(&ctbl->nfree, clipt_size);
302 	rwlock_init(&ctbl->lock);
303 
304 	for (i = 0; i < ctbl->clipt_size; ++i)
305 		INIT_LIST_HEAD(&ctbl->hash_list[i]);
306 
307 	cl_list = kvzalloc(clipt_size*sizeof(struct clip_entry), GFP_KERNEL);
308 	if (!cl_list) {
309 		kvfree(ctbl);
310 		return NULL;
311 	}
312 	ctbl->cl_list = (void *)cl_list;
313 
314 	for (i = 0; i < clipt_size; i++) {
315 		INIT_LIST_HEAD(&cl_list[i].list);
316 		list_add_tail(&cl_list[i].list, &ctbl->ce_free_head);
317 	}
318 
319 	return ctbl;
320 }
321 
322 void t4_cleanup_clip_tbl(struct adapter *adap)
323 {
324 	struct clip_tbl *ctbl = adap->clipt;
325 
326 	if (ctbl) {
327 		if (ctbl->cl_list)
328 			kvfree(ctbl->cl_list);
329 		kvfree(ctbl);
330 	}
331 }
332 EXPORT_SYMBOL(t4_cleanup_clip_tbl);
333