[NET_SCHED] qdisc: avoid transmit softirq on watchdog wakeup
[linux-2.6] / net / sched / act_gact.c
1 /*
2  * net/sched/gact.c     Generic actions
3  *
4  *              This program is free software; you can redistribute it and/or
5  *              modify it under the terms of the GNU General Public License
6  *              as published by the Free Software Foundation; either version
7  *              2 of the License, or (at your option) any later version.
8  *
9  * copyright    Jamal Hadi Salim (2002-4)
10  *
11  */
12
13 #include <asm/uaccess.h>
14 #include <asm/system.h>
15 #include <linux/bitops.h>
16 #include <linux/types.h>
17 #include <linux/kernel.h>
18 #include <linux/string.h>
19 #include <linux/mm.h>
20 #include <linux/socket.h>
21 #include <linux/sockios.h>
22 #include <linux/in.h>
23 #include <linux/errno.h>
24 #include <linux/interrupt.h>
25 #include <linux/netdevice.h>
26 #include <linux/skbuff.h>
27 #include <linux/rtnetlink.h>
28 #include <linux/module.h>
29 #include <linux/init.h>
30 #include <linux/proc_fs.h>
31 #include <net/netlink.h>
32 #include <net/sock.h>
33 #include <net/pkt_sched.h>
34 #include <linux/tc_act/tc_gact.h>
35 #include <net/tc_act/tc_gact.h>
36
37 #define GACT_TAB_MASK   15
38 static struct tcf_common *tcf_gact_ht[GACT_TAB_MASK + 1];
39 static u32 gact_idx_gen;
40 static DEFINE_RWLOCK(gact_lock);
41
42 static struct tcf_hashinfo gact_hash_info = {
43         .htab   =       tcf_gact_ht,
44         .hmask  =       GACT_TAB_MASK,
45         .lock   =       &gact_lock,
46 };
47
48 #ifdef CONFIG_GACT_PROB
49 static int gact_net_rand(struct tcf_gact *gact)
50 {
51         if (!gact->tcfg_pval || net_random() % gact->tcfg_pval)
52                 return gact->tcf_action;
53         return gact->tcfg_paction;
54 }
55
56 static int gact_determ(struct tcf_gact *gact)
57 {
58         if (!gact->tcfg_pval || gact->tcf_bstats.packets % gact->tcfg_pval)
59                 return gact->tcf_action;
60         return gact->tcfg_paction;
61 }
62
63 typedef int (*g_rand)(struct tcf_gact *gact);
64 static g_rand gact_rand[MAX_RAND]= { NULL, gact_net_rand, gact_determ };
65 #endif /* CONFIG_GACT_PROB */
66
67 static int tcf_gact_init(struct rtattr *rta, struct rtattr *est,
68                          struct tc_action *a, int ovr, int bind)
69 {
70         struct rtattr *tb[TCA_GACT_MAX];
71         struct tc_gact *parm;
72         struct tcf_gact *gact;
73         struct tcf_common *pc;
74         int ret = 0;
75
76         if (rta == NULL || rtattr_parse_nested(tb, TCA_GACT_MAX, rta) < 0)
77                 return -EINVAL;
78
79         if (tb[TCA_GACT_PARMS - 1] == NULL ||
80             RTA_PAYLOAD(tb[TCA_GACT_PARMS - 1]) < sizeof(*parm))
81                 return -EINVAL;
82         parm = RTA_DATA(tb[TCA_GACT_PARMS - 1]);
83
84         if (tb[TCA_GACT_PROB-1] != NULL)
85 #ifdef CONFIG_GACT_PROB
86                 if (RTA_PAYLOAD(tb[TCA_GACT_PROB-1]) < sizeof(struct tc_gact_p))
87                         return -EINVAL;
88 #else
89                 return -EOPNOTSUPP;
90 #endif
91
92         pc = tcf_hash_check(parm->index, a, bind, &gact_hash_info);
93         if (!pc) {
94                 pc = tcf_hash_create(parm->index, est, a, sizeof(*gact),
95                                      bind, &gact_idx_gen, &gact_hash_info);
96                 if (unlikely(!pc))
97                         return -ENOMEM;
98                 ret = ACT_P_CREATED;
99         } else {
100                 if (!ovr) {
101                         tcf_hash_release(pc, bind, &gact_hash_info);
102                         return -EEXIST;
103                 }
104         }
105
106         gact = to_gact(pc);
107
108         spin_lock_bh(&gact->tcf_lock);
109         gact->tcf_action = parm->action;
110 #ifdef CONFIG_GACT_PROB
111         if (tb[TCA_GACT_PROB-1] != NULL) {
112                 struct tc_gact_p *p_parm = RTA_DATA(tb[TCA_GACT_PROB-1]);
113                 gact->tcfg_paction = p_parm->paction;
114                 gact->tcfg_pval    = p_parm->pval;
115                 gact->tcfg_ptype   = p_parm->ptype;
116         }
117 #endif
118         spin_unlock_bh(&gact->tcf_lock);
119         if (ret == ACT_P_CREATED)
120                 tcf_hash_insert(pc, &gact_hash_info);
121         return ret;
122 }
123
124 static int tcf_gact_cleanup(struct tc_action *a, int bind)
125 {
126         struct tcf_gact *gact = a->priv;
127
128         if (gact)
129                 return tcf_hash_release(&gact->common, bind, &gact_hash_info);
130         return 0;
131 }
132
133 static int tcf_gact(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res)
134 {
135         struct tcf_gact *gact = a->priv;
136         int action = TC_ACT_SHOT;
137
138         spin_lock(&gact->tcf_lock);
139 #ifdef CONFIG_GACT_PROB
140         if (gact->tcfg_ptype && gact_rand[gact->tcfg_ptype] != NULL)
141                 action = gact_rand[gact->tcfg_ptype](gact);
142         else
143                 action = gact->tcf_action;
144 #else
145         action = gact->tcf_action;
146 #endif
147         gact->tcf_bstats.bytes += skb->len;
148         gact->tcf_bstats.packets++;
149         if (action == TC_ACT_SHOT)
150                 gact->tcf_qstats.drops++;
151         gact->tcf_tm.lastuse = jiffies;
152         spin_unlock(&gact->tcf_lock);
153
154         return action;
155 }
156
157 static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
158 {
159         unsigned char *b = skb_tail_pointer(skb);
160         struct tc_gact opt;
161         struct tcf_gact *gact = a->priv;
162         struct tcf_t t;
163
164         opt.index = gact->tcf_index;
165         opt.refcnt = gact->tcf_refcnt - ref;
166         opt.bindcnt = gact->tcf_bindcnt - bind;
167         opt.action = gact->tcf_action;
168         RTA_PUT(skb, TCA_GACT_PARMS, sizeof(opt), &opt);
169 #ifdef CONFIG_GACT_PROB
170         if (gact->tcfg_ptype) {
171                 struct tc_gact_p p_opt;
172                 p_opt.paction = gact->tcfg_paction;
173                 p_opt.pval = gact->tcfg_pval;
174                 p_opt.ptype = gact->tcfg_ptype;
175                 RTA_PUT(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt);
176         }
177 #endif
178         t.install = jiffies_to_clock_t(jiffies - gact->tcf_tm.install);
179         t.lastuse = jiffies_to_clock_t(jiffies - gact->tcf_tm.lastuse);
180         t.expires = jiffies_to_clock_t(gact->tcf_tm.expires);
181         RTA_PUT(skb, TCA_GACT_TM, sizeof(t), &t);
182         return skb->len;
183
184 rtattr_failure:
185         nlmsg_trim(skb, b);
186         return -1;
187 }
188
189 static struct tc_action_ops act_gact_ops = {
190         .kind           =       "gact",
191         .hinfo          =       &gact_hash_info,
192         .type           =       TCA_ACT_GACT,
193         .capab          =       TCA_CAP_NONE,
194         .owner          =       THIS_MODULE,
195         .act            =       tcf_gact,
196         .dump           =       tcf_gact_dump,
197         .cleanup        =       tcf_gact_cleanup,
198         .lookup         =       tcf_hash_search,
199         .init           =       tcf_gact_init,
200         .walk           =       tcf_generic_walker
201 };
202
203 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
204 MODULE_DESCRIPTION("Generic Classifier actions");
205 MODULE_LICENSE("GPL");
206
207 static int __init gact_init_module(void)
208 {
209 #ifdef CONFIG_GACT_PROB
210         printk("GACT probability on\n");
211 #else
212         printk("GACT probability NOT on\n");
213 #endif
214         return tcf_register_action(&act_gact_ops);
215 }
216
217 static void __exit gact_cleanup_module(void)
218 {
219         tcf_unregister_action(&act_gact_ops);
220 }
221
222 module_init(gact_init_module);
223 module_exit(gact_cleanup_module);