]> asedeno.scripts.mit.edu Git - linux.git/blob - drivers/net/ethernet/chelsio/cxgb4/clip_tbl.c
bsg: fix race of bsg_open and bsg_unregister
[linux.git] / drivers / net / ethernet / chelsio / cxgb4 / clip_tbl.c
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);