android_kernel_xiaomi_sm8350/net/sched/cls_u32.c
Radu Rendec b226801676 [PKT_SCHED] CLS_U32: Use ffs() instead of C code on hash mask to get first set bit.
Computing the rank of the first set bit in the hash mask (for using later
in u32_hash_fold()) was done with plain C code. Using ffs() instead makes
the code more readable and improves performance (since ffs() is better
optimized in assembler).

Using the conditional operator on hash mask before applying ntohl() also
saves one ntohl() call if mask is 0.

Signed-off-by: Radu Rendec <radu.rendec@ines.ro>
Signed-off-by: Jarek Poplawski <jarkao2@o2.pl>
Acked-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-10 21:54:50 -08:00

792 lines
16 KiB
C

/*
* net/sched/cls_u32.c Ugly (or Universal) 32bit key Packet Classifier.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*
* The filters are packed to hash tables of key nodes
* with a set of 32bit key/mask pairs at every node.
* Nodes reference next level hash tables etc.
*
* This scheme is the best universal classifier I managed to
* invent; it is not super-fast, but it is not slow (provided you
* program it correctly), and general enough. And its relative
* speed grows as the number of rules becomes larger.
*
* It seems that it represents the best middle point between
* speed and manageability both by human and by machine.
*
* It is especially useful for link sharing combined with QoS;
* pure RSVP doesn't need such a general approach and can use
* much simpler (and faster) schemes, sort of cls_rsvp.c.
*
* JHS: We should remove the CONFIG_NET_CLS_IND from here
* eventually when the meta match extension is made available
*
* nfmark match added by Catalin(ux aka Dino) BOIE <catab at umbrella.ro>
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/rtnetlink.h>
#include <linux/skbuff.h>
#include <net/netlink.h>
#include <net/act_api.h>
#include <net/pkt_cls.h>
struct tc_u_knode
{
struct tc_u_knode *next;
u32 handle;
struct tc_u_hnode *ht_up;
struct tcf_exts exts;
#ifdef CONFIG_NET_CLS_IND
char indev[IFNAMSIZ];
#endif
u8 fshift;
struct tcf_result res;
struct tc_u_hnode *ht_down;
#ifdef CONFIG_CLS_U32_PERF
struct tc_u32_pcnt *pf;
#endif
#ifdef CONFIG_CLS_U32_MARK
struct tc_u32_mark mark;
#endif
struct tc_u32_sel sel;
};
struct tc_u_hnode
{
struct tc_u_hnode *next;
u32 handle;
u32 prio;
struct tc_u_common *tp_c;
int refcnt;
unsigned divisor;
struct tc_u_knode *ht[1];
};
struct tc_u_common
{
struct tc_u_common *next;
struct tc_u_hnode *hlist;
struct Qdisc *q;
int refcnt;
u32 hgenerator;
};
static struct tcf_ext_map u32_ext_map = {
.action = TCA_U32_ACT,
.police = TCA_U32_POLICE
};
static struct tc_u_common *u32_list;
static __inline__ unsigned u32_hash_fold(u32 key, struct tc_u32_sel *sel, u8 fshift)
{
unsigned h = ntohl(key & sel->hmask)>>fshift;
return h;
}
static int u32_classify(struct sk_buff *skb, struct tcf_proto *tp, struct tcf_result *res)
{
struct {
struct tc_u_knode *knode;
u8 *ptr;
} stack[TC_U32_MAXDEPTH];
struct tc_u_hnode *ht = (struct tc_u_hnode*)tp->root;
u8 *ptr = skb_network_header(skb);
struct tc_u_knode *n;
int sdepth = 0;
int off2 = 0;
int sel = 0;
#ifdef CONFIG_CLS_U32_PERF
int j;
#endif
int i, r;
next_ht:
n = ht->ht[sel];
next_knode:
if (n) {
struct tc_u32_key *key = n->sel.keys;
#ifdef CONFIG_CLS_U32_PERF
n->pf->rcnt +=1;
j = 0;
#endif
#ifdef CONFIG_CLS_U32_MARK
if ((skb->mark & n->mark.mask) != n->mark.val) {
n = n->next;
goto next_knode;
} else {
n->mark.success++;
}
#endif
for (i = n->sel.nkeys; i>0; i--, key++) {
if ((*(u32*)(ptr+key->off+(off2&key->offmask))^key->val)&key->mask) {
n = n->next;
goto next_knode;
}
#ifdef CONFIG_CLS_U32_PERF
n->pf->kcnts[j] +=1;
j++;
#endif
}
if (n->ht_down == NULL) {
check_terminal:
if (n->sel.flags&TC_U32_TERMINAL) {
*res = n->res;
#ifdef CONFIG_NET_CLS_IND
if (!tcf_match_indev(skb, n->indev)) {
n = n->next;
goto next_knode;
}
#endif
#ifdef CONFIG_CLS_U32_PERF
n->pf->rhit +=1;
#endif
r = tcf_exts_exec(skb, &n->exts, res);
if (r < 0) {
n = n->next;
goto next_knode;
}
return r;
}
n = n->next;
goto next_knode;
}
/* PUSH */
if (sdepth >= TC_U32_MAXDEPTH)
goto deadloop;
stack[sdepth].knode = n;
stack[sdepth].ptr = ptr;
sdepth++;
ht = n->ht_down;
sel = 0;
if (ht->divisor)
sel = ht->divisor&u32_hash_fold(*(u32*)(ptr+n->sel.hoff), &n->sel,n->fshift);
if (!(n->sel.flags&(TC_U32_VAROFFSET|TC_U32_OFFSET|TC_U32_EAT)))
goto next_ht;
if (n->sel.flags&(TC_U32_OFFSET|TC_U32_VAROFFSET)) {
off2 = n->sel.off + 3;
if (n->sel.flags&TC_U32_VAROFFSET)
off2 += ntohs(n->sel.offmask & *(u16*)(ptr+n->sel.offoff)) >>n->sel.offshift;
off2 &= ~3;
}
if (n->sel.flags&TC_U32_EAT) {
ptr += off2;
off2 = 0;
}
if (ptr < skb_tail_pointer(skb))
goto next_ht;
}
/* POP */
if (sdepth--) {
n = stack[sdepth].knode;
ht = n->ht_up;
ptr = stack[sdepth].ptr;
goto check_terminal;
}
return -1;
deadloop:
if (net_ratelimit())
printk("cls_u32: dead loop\n");
return -1;
}
static __inline__ struct tc_u_hnode *
u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
{
struct tc_u_hnode *ht;
for (ht = tp_c->hlist; ht; ht = ht->next)
if (ht->handle == handle)
break;
return ht;
}
static __inline__ struct tc_u_knode *
u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
{
unsigned sel;
struct tc_u_knode *n = NULL;
sel = TC_U32_HASH(handle);
if (sel > ht->divisor)
goto out;
for (n = ht->ht[sel]; n; n = n->next)
if (n->handle == handle)
break;
out:
return n;
}
static unsigned long u32_get(struct tcf_proto *tp, u32 handle)
{
struct tc_u_hnode *ht;
struct tc_u_common *tp_c = tp->data;
if (TC_U32_HTID(handle) == TC_U32_ROOT)
ht = tp->root;
else
ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
if (!ht)
return 0;
if (TC_U32_KEY(handle) == 0)
return (unsigned long)ht;
return (unsigned long)u32_lookup_key(ht, handle);
}
static void u32_put(struct tcf_proto *tp, unsigned long f)
{
}
static u32 gen_new_htid(struct tc_u_common *tp_c)
{
int i = 0x800;
do {
if (++tp_c->hgenerator == 0x7FF)
tp_c->hgenerator = 1;
} while (--i>0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20));
return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0;
}
static int u32_init(struct tcf_proto *tp)
{
struct tc_u_hnode *root_ht;
struct tc_u_common *tp_c;
for (tp_c = u32_list; tp_c; tp_c = tp_c->next)
if (tp_c->q == tp->q)
break;
root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL);
if (root_ht == NULL)
return -ENOBUFS;
root_ht->divisor = 0;
root_ht->refcnt++;
root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
root_ht->prio = tp->prio;
if (tp_c == NULL) {
tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
if (tp_c == NULL) {
kfree(root_ht);
return -ENOBUFS;
}
tp_c->q = tp->q;
tp_c->next = u32_list;
u32_list = tp_c;
}
tp_c->refcnt++;
root_ht->next = tp_c->hlist;
tp_c->hlist = root_ht;
root_ht->tp_c = tp_c;
tp->root = root_ht;
tp->data = tp_c;
return 0;
}
static int u32_destroy_key(struct tcf_proto *tp, struct tc_u_knode *n)
{
tcf_unbind_filter(tp, &n->res);
tcf_exts_destroy(tp, &n->exts);
if (n->ht_down)
n->ht_down->refcnt--;
#ifdef CONFIG_CLS_U32_PERF
kfree(n->pf);
#endif
kfree(n);
return 0;
}
static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode* key)
{
struct tc_u_knode **kp;
struct tc_u_hnode *ht = key->ht_up;
if (ht) {
for (kp = &ht->ht[TC_U32_HASH(key->handle)]; *kp; kp = &(*kp)->next) {
if (*kp == key) {
tcf_tree_lock(tp);
*kp = key->next;
tcf_tree_unlock(tp);
u32_destroy_key(tp, key);
return 0;
}
}
}
BUG_TRAP(0);
return 0;
}
static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
{
struct tc_u_knode *n;
unsigned h;
for (h=0; h<=ht->divisor; h++) {
while ((n = ht->ht[h]) != NULL) {
ht->ht[h] = n->next;
u32_destroy_key(tp, n);
}
}
}
static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_hnode **hn;
BUG_TRAP(!ht->refcnt);
u32_clear_hnode(tp, ht);
for (hn = &tp_c->hlist; *hn; hn = &(*hn)->next) {
if (*hn == ht) {
*hn = ht->next;
kfree(ht);
return 0;
}
}
BUG_TRAP(0);
return -ENOENT;
}
static void u32_destroy(struct tcf_proto *tp)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_hnode *root_ht = xchg(&tp->root, NULL);
BUG_TRAP(root_ht != NULL);
if (root_ht && --root_ht->refcnt == 0)
u32_destroy_hnode(tp, root_ht);
if (--tp_c->refcnt == 0) {
struct tc_u_hnode *ht;
struct tc_u_common **tp_cp;
for (tp_cp = &u32_list; *tp_cp; tp_cp = &(*tp_cp)->next) {
if (*tp_cp == tp_c) {
*tp_cp = tp_c->next;
break;
}
}
for (ht=tp_c->hlist; ht; ht = ht->next)
u32_clear_hnode(tp, ht);
while ((ht = tp_c->hlist) != NULL) {
tp_c->hlist = ht->next;
BUG_TRAP(ht->refcnt == 0);
kfree(ht);
}
kfree(tp_c);
}
tp->data = NULL;
}
static int u32_delete(struct tcf_proto *tp, unsigned long arg)
{
struct tc_u_hnode *ht = (struct tc_u_hnode*)arg;
if (ht == NULL)
return 0;
if (TC_U32_KEY(ht->handle))
return u32_delete_key(tp, (struct tc_u_knode*)ht);
if (tp->root == ht)
return -EINVAL;
if (--ht->refcnt == 0)
u32_destroy_hnode(tp, ht);
return 0;
}
static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle)
{
struct tc_u_knode *n;
unsigned i = 0x7FF;
for (n=ht->ht[TC_U32_HASH(handle)]; n; n = n->next)
if (i < TC_U32_NODE(n->handle))
i = TC_U32_NODE(n->handle);
i++;
return handle|(i>0xFFF ? 0xFFF : i);
}
static int u32_set_parms(struct tcf_proto *tp, unsigned long base,
struct tc_u_hnode *ht,
struct tc_u_knode *n, struct rtattr **tb,
struct rtattr *est)
{
int err;
struct tcf_exts e;
err = tcf_exts_validate(tp, tb, est, &e, &u32_ext_map);
if (err < 0)
return err;
err = -EINVAL;
if (tb[TCA_U32_LINK-1]) {
u32 handle = *(u32*)RTA_DATA(tb[TCA_U32_LINK-1]);
struct tc_u_hnode *ht_down = NULL;
if (TC_U32_KEY(handle))
goto errout;
if (handle) {
ht_down = u32_lookup_ht(ht->tp_c, handle);
if (ht_down == NULL)
goto errout;
ht_down->refcnt++;
}
tcf_tree_lock(tp);
ht_down = xchg(&n->ht_down, ht_down);
tcf_tree_unlock(tp);
if (ht_down)
ht_down->refcnt--;
}
if (tb[TCA_U32_CLASSID-1]) {
n->res.classid = *(u32*)RTA_DATA(tb[TCA_U32_CLASSID-1]);
tcf_bind_filter(tp, &n->res, base);
}
#ifdef CONFIG_NET_CLS_IND
if (tb[TCA_U32_INDEV-1]) {
err = tcf_change_indev(tp, n->indev, tb[TCA_U32_INDEV-1]);
if (err < 0)
goto errout;
}
#endif
tcf_exts_change(tp, &n->exts, &e);
return 0;
errout:
tcf_exts_destroy(tp, &e);
return err;
}
static int u32_change(struct tcf_proto *tp, unsigned long base, u32 handle,
struct rtattr **tca,
unsigned long *arg)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_hnode *ht;
struct tc_u_knode *n;
struct tc_u32_sel *s;
struct rtattr *opt = tca[TCA_OPTIONS-1];
struct rtattr *tb[TCA_U32_MAX];
u32 htid;
int err;
if (opt == NULL)
return handle ? -EINVAL : 0;
if (rtattr_parse_nested(tb, TCA_U32_MAX, opt) < 0)
return -EINVAL;
if ((n = (struct tc_u_knode*)*arg) != NULL) {
if (TC_U32_KEY(n->handle) == 0)
return -EINVAL;
return u32_set_parms(tp, base, n->ht_up, n, tb, tca[TCA_RATE-1]);
}
if (tb[TCA_U32_DIVISOR-1]) {
unsigned divisor = *(unsigned*)RTA_DATA(tb[TCA_U32_DIVISOR-1]);
if (--divisor > 0x100)
return -EINVAL;
if (TC_U32_KEY(handle))
return -EINVAL;
if (handle == 0) {
handle = gen_new_htid(tp->data);
if (handle == 0)
return -ENOMEM;
}
ht = kzalloc(sizeof(*ht) + divisor*sizeof(void*), GFP_KERNEL);
if (ht == NULL)
return -ENOBUFS;
ht->tp_c = tp_c;
ht->refcnt = 0;
ht->divisor = divisor;
ht->handle = handle;
ht->prio = tp->prio;
ht->next = tp_c->hlist;
tp_c->hlist = ht;
*arg = (unsigned long)ht;
return 0;
}
if (tb[TCA_U32_HASH-1]) {
htid = *(unsigned*)RTA_DATA(tb[TCA_U32_HASH-1]);
if (TC_U32_HTID(htid) == TC_U32_ROOT) {
ht = tp->root;
htid = ht->handle;
} else {
ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
if (ht == NULL)
return -EINVAL;
}
} else {
ht = tp->root;
htid = ht->handle;
}
if (ht->divisor < TC_U32_HASH(htid))
return -EINVAL;
if (handle) {
if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid))
return -EINVAL;
handle = htid | TC_U32_NODE(handle);
} else
handle = gen_new_kid(ht, htid);
if (tb[TCA_U32_SEL-1] == NULL ||
RTA_PAYLOAD(tb[TCA_U32_SEL-1]) < sizeof(struct tc_u32_sel))
return -EINVAL;
s = RTA_DATA(tb[TCA_U32_SEL-1]);
n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL);
if (n == NULL)
return -ENOBUFS;
#ifdef CONFIG_CLS_U32_PERF
n->pf = kzalloc(sizeof(struct tc_u32_pcnt) + s->nkeys*sizeof(u64), GFP_KERNEL);
if (n->pf == NULL) {
kfree(n);
return -ENOBUFS;
}
#endif
memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
n->ht_up = ht;
n->handle = handle;
n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
#ifdef CONFIG_CLS_U32_MARK
if (tb[TCA_U32_MARK-1]) {
struct tc_u32_mark *mark;
if (RTA_PAYLOAD(tb[TCA_U32_MARK-1]) < sizeof(struct tc_u32_mark)) {
#ifdef CONFIG_CLS_U32_PERF
kfree(n->pf);
#endif
kfree(n);
return -EINVAL;
}
mark = RTA_DATA(tb[TCA_U32_MARK-1]);
memcpy(&n->mark, mark, sizeof(struct tc_u32_mark));
n->mark.success = 0;
}
#endif
err = u32_set_parms(tp, base, ht, n, tb, tca[TCA_RATE-1]);
if (err == 0) {
struct tc_u_knode **ins;
for (ins = &ht->ht[TC_U32_HASH(handle)]; *ins; ins = &(*ins)->next)
if (TC_U32_NODE(handle) < TC_U32_NODE((*ins)->handle))
break;
n->next = *ins;
wmb();
*ins = n;
*arg = (unsigned long)n;
return 0;
}
#ifdef CONFIG_CLS_U32_PERF
kfree(n->pf);
#endif
kfree(n);
return err;
}
static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_hnode *ht;
struct tc_u_knode *n;
unsigned h;
if (arg->stop)
return;
for (ht = tp_c->hlist; ht; ht = ht->next) {
if (ht->prio != tp->prio)
continue;
if (arg->count >= arg->skip) {
if (arg->fn(tp, (unsigned long)ht, arg) < 0) {
arg->stop = 1;
return;
}
}
arg->count++;
for (h = 0; h <= ht->divisor; h++) {
for (n = ht->ht[h]; n; n = n->next) {
if (arg->count < arg->skip) {
arg->count++;
continue;
}
if (arg->fn(tp, (unsigned long)n, arg) < 0) {
arg->stop = 1;
return;
}
arg->count++;
}
}
}
}
static int u32_dump(struct tcf_proto *tp, unsigned long fh,
struct sk_buff *skb, struct tcmsg *t)
{
struct tc_u_knode *n = (struct tc_u_knode*)fh;
unsigned char *b = skb_tail_pointer(skb);
struct rtattr *rta;
if (n == NULL)
return skb->len;
t->tcm_handle = n->handle;
rta = (struct rtattr*)b;
RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
if (TC_U32_KEY(n->handle) == 0) {
struct tc_u_hnode *ht = (struct tc_u_hnode*)fh;
u32 divisor = ht->divisor+1;
RTA_PUT(skb, TCA_U32_DIVISOR, 4, &divisor);
} else {
RTA_PUT(skb, TCA_U32_SEL,
sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
&n->sel);
if (n->ht_up) {
u32 htid = n->handle & 0xFFFFF000;
RTA_PUT(skb, TCA_U32_HASH, 4, &htid);
}
if (n->res.classid)
RTA_PUT(skb, TCA_U32_CLASSID, 4, &n->res.classid);
if (n->ht_down)
RTA_PUT(skb, TCA_U32_LINK, 4, &n->ht_down->handle);
#ifdef CONFIG_CLS_U32_MARK
if (n->mark.val || n->mark.mask)
RTA_PUT(skb, TCA_U32_MARK, sizeof(n->mark), &n->mark);
#endif
if (tcf_exts_dump(skb, &n->exts, &u32_ext_map) < 0)
goto rtattr_failure;
#ifdef CONFIG_NET_CLS_IND
if(strlen(n->indev))
RTA_PUT(skb, TCA_U32_INDEV, IFNAMSIZ, n->indev);
#endif
#ifdef CONFIG_CLS_U32_PERF
RTA_PUT(skb, TCA_U32_PCNT,
sizeof(struct tc_u32_pcnt) + n->sel.nkeys*sizeof(u64),
n->pf);
#endif
}
rta->rta_len = skb_tail_pointer(skb) - b;
if (TC_U32_KEY(n->handle))
if (tcf_exts_dump_stats(skb, &n->exts, &u32_ext_map) < 0)
goto rtattr_failure;
return skb->len;
rtattr_failure:
nlmsg_trim(skb, b);
return -1;
}
static struct tcf_proto_ops cls_u32_ops = {
.next = NULL,
.kind = "u32",
.classify = u32_classify,
.init = u32_init,
.destroy = u32_destroy,
.get = u32_get,
.put = u32_put,
.change = u32_change,
.delete = u32_delete,
.walk = u32_walk,
.dump = u32_dump,
.owner = THIS_MODULE,
};
static int __init init_u32(void)
{
printk("u32 classifier\n");
#ifdef CONFIG_CLS_U32_PERF
printk(" Performance counters on\n");
#endif
#ifdef CONFIG_NET_CLS_IND
printk(" input device check on \n");
#endif
#ifdef CONFIG_NET_CLS_ACT
printk(" Actions configured \n");
#endif
return register_tcf_proto_ops(&cls_u32_ops);
}
static void __exit exit_u32(void)
{
unregister_tcf_proto_ops(&cls_u32_ops);
}
module_init(init_u32)
module_exit(exit_u32)
MODULE_LICENSE("GPL");