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_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 }
144 EXPORT_SYMBOL(cxgb4_clip_get);
145 
146 void 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;
177 found:
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 }
190 EXPORT_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  */
196 static 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 
218 int 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 }
248 EXPORT_SYMBOL(cxgb4_update_root_dev_clip);
249 
250 int 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 
276 struct 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 
319 void 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 }
328 EXPORT_SYMBOL(t4_cleanup_clip_tbl);
329