patch-2.1.99 linux/net/sched/cls_u32.c

Next file: linux/net/sched/estimator.c
Previous file: linux/net/sched/cls_rsvp6.c
Back to the patch index
Back to the overall index

diff -u --recursive --new-file v2.1.98/linux/net/sched/cls_u32.c linux/net/sched/cls_u32.c
@@ -0,0 +1,704 @@
+/*
+ * 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 programmed it correctly), and enough general.
+ *	And its relative speed grows, when number of rules becomes larger.
+ *
+ *	Seems, it presents the best middle point between speed and
+ *	managability both by human and by machine.
+ *
+ *	It is especially useful for link sharing and link sharing, combined
+ *	with QoS; pure RSVP need not such general approach and can use
+ *	much simpler (and faster) schemes, sort of cls_rsvp.c.
+ */
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/bitops.h>
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/in.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/if_ether.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/notifier.h>
+#include <linux/rtnetlink.h>
+#include <net/ip.h>
+#include <net/route.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/pkt_sched.h>
+
+#define BUG_TRAP(x) if (!(x)) { printk("Assertion (" #x ") failed at " __FILE__ "(%d):" __FUNCTION__ "\n", __LINE__); }
+
+
+struct tc_u_knode
+{
+	struct tc_u_knode	*next;
+	u32			handle;
+	struct tc_u_hnode	*ht_up;
+#ifdef CONFIG_NET_CLS_POLICE
+	struct tcf_police	*police;
+#endif
+	struct tcf_result	res;
+	struct tc_u_hnode	*ht_down;
+	struct tc_u32_sel	sel;
+};
+
+struct tc_u_hnode
+{
+	struct tc_u_hnode	*next;
+	u32			handle;
+	struct tc_u_common	*tp_c;
+	int			refcnt;
+	unsigned		divisor;
+	u32			hgenerator;
+	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 tc_u_common *u32_list;
+
+static __inline__ unsigned u32_hash_fold(u32 key, struct tc_u32_sel *sel)
+{
+	unsigned h = key & sel->hmask;
+
+	h ^= h>>16;
+	h ^= h>>8;
+	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->nh.raw;
+	struct tc_u_knode *n;
+	int sdepth = 0;
+	int off2 = 0;
+	int sel = 0;
+	int i;
+
+#ifndef __i386__
+	if ((unsigned long)ptr & 3)
+		return -1;
+#endif
+
+next_ht:
+	n = ht->ht[sel];
+
+next_knode:
+	if (n) {
+		struct tc_u32_key *key = n->sel.keys;
+
+		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;
+			}
+		}
+		if (n->ht_down == NULL) {
+check_terminal:
+			if (n->sel.flags&TC_U32_TERMINAL) {
+				*res = n->res;
+#ifdef CONFIG_NET_CLS_POLICE
+				if (n->police)
+					return tcf_police(skb, n->police);
+#endif
+				return 0;
+			}
+			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);
+
+		if (!(n->sel.flags&(TC_U32_VAROFFSET|TC_U32_OFFSET|TC_U32_EAT)))
+			goto next_ht;
+
+		if (n->sel.flags&(TC_U32_EAT|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)
+			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;
+
+	sel = TC_U32_HASH(handle);
+	if (sel > ht->divisor)
+		return 0;
+
+	for (n = ht->ht[sel]; n; n = n->next)
+		if (n->handle == handle)
+			return n;
+
+	return NULL;
+}
+
+
+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;
+
+	MOD_INC_USE_COUNT;
+
+	for (tp_c = u32_list; tp_c; tp_c = tp_c->next)
+		if (tp_c->q == tp->q)
+			break;
+
+	root_ht = kmalloc(sizeof(*root_ht), GFP_KERNEL);
+	if (root_ht == NULL) {
+		MOD_DEC_USE_COUNT;
+		return -ENOBUFS;
+	}
+	memset(root_ht, 0, sizeof(*root_ht));
+	root_ht->divisor = 0;
+	root_ht->refcnt++;
+	root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
+
+	if (tp_c == NULL) {
+		tp_c = kmalloc(sizeof(*tp_c), GFP_KERNEL);
+		if (tp_c == NULL) {
+			kfree(root_ht);
+			MOD_DEC_USE_COUNT;
+			return -ENOBUFS;
+		}
+		memset(tp_c, 0, sizeof(*tp_c));
+		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)
+{
+	unsigned long cl;
+
+	if ((cl = xchg(&n->res.class, 0)) != 0)
+		tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
+#ifdef CONFIG_NET_CLS_POLICE
+	tcf_police_release(n->police);
+#endif
+	if (n->ht_down)
+		n->ht_down->refcnt--;
+	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) {
+				*kp = key->next;
+				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 Qdisc *q, struct tc_u_hnode *ht,
+			 struct tc_u_knode *n, struct rtattr **tb)
+{
+	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))
+			return -EINVAL;
+
+		if (handle) {
+			ht_down = u32_lookup_ht(ht->tp_c, handle);
+
+			if (ht_down == NULL)
+				return -EINVAL;
+			ht_down->refcnt++;
+		}
+
+		ht_down = xchg(&n->ht_down, ht_down);
+
+		if (ht_down)
+			ht_down->refcnt--;
+	}
+	if (tb[TCA_U32_CLASSID-1]) {
+		unsigned long cl = xchg(&n->res.class, 0);
+		if (cl)
+			q->ops->cl_ops->unbind_tcf(q, cl);
+		n->res.classid = *(u32*)RTA_DATA(tb[TCA_U32_CLASSID-1]);
+		n->res.class = q->ops->cl_ops->bind_tcf(q, n->res.classid);
+	}
+#ifdef CONFIG_NET_CLS_POLICE
+	if (tb[TCA_U32_POLICE-1]) {
+		struct tcf_police *police = tcf_police_locate(tb[TCA_U32_POLICE-1]);
+
+		tcf_police_release(xchg(&n->police, police));
+	}
+#endif
+	return 0;
+}
+
+static int u32_change(struct tcf_proto *tp, 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(tb, TCA_U32_MAX, RTA_DATA(opt), RTA_PAYLOAD(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->q, n->ht_up, n, tb);
+	}
+
+	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 = kmalloc(sizeof(*ht) + divisor*sizeof(void*), GFP_KERNEL);
+		if (ht == NULL)
+			return -ENOBUFS;
+		memset(ht, 0, sizeof(*ht) + divisor*sizeof(void*));
+		ht->tp_c = tp_c;
+		ht->refcnt = 0;
+		ht->divisor = divisor;
+		ht->handle = handle;
+		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(handle) == 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;
+		if (TC_U32_HASH(handle) && TC_U32_HASH(handle^htid))
+			return -EINVAL;
+		handle = htid | TC_U32_NODE(handle);
+	} else
+		handle = gen_new_kid(ht, htid);
+
+	if (tb[TCA_U32_SEL-1] == 0 ||
+	    RTA_PAYLOAD(tb[TCA_U32_SEL-1]) < sizeof(struct tc_u32_sel))
+		return -EINVAL;
+
+	s = RTA_DATA(tb[TCA_U32_SEL-1]);
+	n = kmalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL);
+	if (n == NULL)
+		return -ENOBUFS;
+	memset(n, 0, sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key));
+	memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
+	n->ht_up = ht;
+	n->handle = handle;
+	err = u32_set_parms(tp->q, ht, n, tb);
+	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;
+		*ins = n;
+		*arg = (unsigned long)n;
+		return 0;
+	}
+	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 (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++;
+			}
+		}
+	}
+}
+
+#ifdef CONFIG_RTNETLINK
+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;
+	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_NET_CLS_POLICE
+		if (n->police) {
+			struct rtattr * p_rta = (struct rtattr*)skb->tail;
+
+			RTA_PUT(skb, TCA_U32_POLICE, 0, NULL);
+
+			if (tcf_police_dump(skb, n->police) < 0)
+				goto rtattr_failure;
+
+			p_rta->rta_len = skb->tail - (u8*)p_rta;
+		}
+#endif
+	}
+
+	rta->rta_len = skb->tail - b;
+	return skb->len;
+
+rtattr_failure:
+	skb_trim(skb, b - skb->data);
+	return -1;
+}
+#endif
+
+struct tcf_proto_ops cls_u32_ops = {
+	NULL,
+	"u32",
+	u32_classify,
+	u32_init,
+	u32_destroy,
+
+	u32_get,
+	u32_put,
+	u32_change,
+	u32_delete,
+	u32_walk,
+#ifdef CONFIG_RTNETLINK
+	u32_dump
+#else
+	NULL
+#endif
+};
+
+#ifdef MODULE
+int init_module(void)
+{
+	return register_tcf_proto_ops(&cls_u32_ops);
+}
+
+void cleanup_module(void) 
+{
+	unregister_tcf_proto_ops(&cls_u32_ops);
+}
+#endif
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov