[deliverable/linux.git] / net / sched / cls_tcindex.c

/*
 * net/sched/cls_tcindex.c	Packet classifier for skb->tc_index
 *
 * Written 1998,1999 by Werner Almesberger, EPFL ICA
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/errno.h>
#include <net/act_api.h>
#include <net/netlink.h>
#include <net/pkt_cls.h>


/*
 * Not quite sure if we need all the xchgs Alexey uses when accessing things.
 * Can always add them later ... :)
 */

/*
 * Passing parameters to the root seems to be done more awkwardly than really
 * necessary. At least, u32 doesn't seem to use such dirty hacks. To be
 * verified. FIXME.
 */

#define PERFECT_HASH_THRESHOLD	64	/* use perfect hash if not bigger */
#define DEFAULT_HASH_SIZE	64	/* optimized for diffserv */


#define	PRIV(tp)	((struct tcindex_data *) (tp)->root)


struct tcindex_filter_result {
	struct tcf_exts		exts;
	struct tcf_result	res;
};

struct tcindex_filter {
	u16 key;
	struct tcindex_filter_result result;
	struct tcindex_filter *next;
};


struct tcindex_data {
	struct tcindex_filter_result *perfect; /* perfect hash; NULL if none */
	struct tcindex_filter **h; /* imperfect hash; only used if !perfect;
				      NULL if unused */
	u16 mask;		/* AND key with mask */
	int shift;		/* shift ANDed key to the right */
	int hash;		/* hash table size; 0 if undefined */
	int alloc_hash;		/* allocated size */
	int fall_through;	/* 0: only classify if explicit match */
};

static const struct tcf_ext_map tcindex_ext_map = {
	.police = TCA_TCINDEX_POLICE,
	.action = TCA_TCINDEX_ACT
};

static inline int
tcindex_filter_is_set(struct tcindex_filter_result *r)
{
	return tcf_exts_is_predicative(&r->exts) || r->res.classid;
}

static struct tcindex_filter_result *
tcindex_lookup(struct tcindex_data *p, u16 key)
{
	struct tcindex_filter *f;

	if (p->perfect)
		return tcindex_filter_is_set(p->perfect + key) ?
			p->perfect + key : NULL;
	else if (p->h) {
		for (f = p->h[key % p->hash]; f; f = f->next)
			if (f->key == key)
				return &f->result;
	}

	return NULL;
}


static int tcindex_classify(struct sk_buff *skb, struct tcf_proto *tp,
			    struct tcf_result *res)
{
	struct tcindex_data *p = PRIV(tp);
	struct tcindex_filter_result *f;
	int key = (skb->tc_index & p->mask) >> p->shift;

	pr_debug("tcindex_classify(skb %p,tp %p,res %p),p %p\n",
		 skb, tp, res, p);

	f = tcindex_lookup(p, key);
	if (!f) {
		if (!p->fall_through)
			return -1;
		res->classid = TC_H_MAKE(TC_H_MAJ(tp->q->handle), key);
		res->class = 0;
		pr_debug("alg 0x%x\n", res->classid);
		return 0;
	}
	*res = f->res;
	pr_debug("map 0x%x\n", res->classid);

	return tcf_exts_exec(skb, &f->exts, res);
}


static unsigned long tcindex_get(struct tcf_proto *tp, u32 handle)
{
	struct tcindex_data *p = PRIV(tp);
	struct tcindex_filter_result *r;

	pr_debug("tcindex_get(tp %p,handle 0x%08x)\n", tp, handle);
	if (p->perfect && handle >= p->alloc_hash)
		return 0;
	r = tcindex_lookup(p, handle);
	return r && tcindex_filter_is_set(r) ? (unsigned long) r : 0UL;
}


static void tcindex_put(struct tcf_proto *tp, unsigned long f)
{
	pr_debug("tcindex_put(tp %p,f 0x%lx)\n", tp, f);
}


static int tcindex_init(struct tcf_proto *tp)
{
	struct tcindex_data *p;

	pr_debug("tcindex_init(tp %p)\n", tp);
	p = kzalloc(sizeof(struct tcindex_data), GFP_KERNEL);
	if (!p)
		return -ENOMEM;

	p->mask = 0xffff;
	p->hash = DEFAULT_HASH_SIZE;
	p->fall_through = 1;

	tp->root = p;
	return 0;
}


static int
__tcindex_delete(struct tcf_proto *tp, unsigned long arg, int lock)
{
	struct tcindex_data *p = PRIV(tp);
	struct tcindex_filter_result *r = (struct tcindex_filter_result *) arg;
	struct tcindex_filter *f = NULL;

	pr_debug("tcindex_delete(tp %p,arg 0x%lx),p %p,f %p\n", tp, arg, p, f);
	if (p->perfect) {
		if (!r->res.class)
			return -ENOENT;
	} else {
		int i;
		struct tcindex_filter **walk = NULL;

		for (i = 0; i < p->hash; i++)
			for (walk = p->h+i; *walk; walk = &(*walk)->next)
				if (&(*walk)->result == r)
					goto found;
		return -ENOENT;

found:
		f = *walk;
		if (lock)
			tcf_tree_lock(tp);
		*walk = f->next;
		if (lock)
			tcf_tree_unlock(tp);
	}
	tcf_unbind_filter(tp, &r->res);
	tcf_exts_destroy(tp, &r->exts);
	kfree(f);
	return 0;
}

static int tcindex_delete(struct tcf_proto *tp, unsigned long arg)
{
	return __tcindex_delete(tp, arg, 1);
}

static inline int
valid_perfect_hash(struct tcindex_data *p)
{
	return  p->hash > (p->mask >> p->shift);
}

static const struct nla_policy tcindex_policy[TCA_TCINDEX_MAX + 1] = {
	[TCA_TCINDEX_HASH]		= { .type = NLA_U32 },
	[TCA_TCINDEX_MASK]		= { .type = NLA_U16 },
	[TCA_TCINDEX_SHIFT]		= { .type = NLA_U32 },
	[TCA_TCINDEX_FALL_THROUGH]	= { .type = NLA_U32 },
	[TCA_TCINDEX_CLASSID]		= { .type = NLA_U32 },
};

static int
tcindex_set_parms(struct tcf_proto *tp, unsigned long base, u32 handle,
		  struct tcindex_data *p, struct tcindex_filter_result *r,
		  struct nlattr **tb, struct nlattr *est)
{
	int err, balloc = 0;
	struct tcindex_filter_result new_filter_result, *old_r = r;
	struct tcindex_filter_result cr;
	struct tcindex_data cp;
	struct tcindex_filter *f = NULL; /* make gcc behave */
	struct tcf_exts e;

	err = tcf_exts_validate(tp, tb, est, &e, &tcindex_ext_map);
	if (err < 0)
		return err;

	memcpy(&cp, p, sizeof(cp));
	memset(&new_filter_result, 0, sizeof(new_filter_result));

	if (old_r)
		memcpy(&cr, r, sizeof(cr));
	else
		memset(&cr, 0, sizeof(cr));

	if (tb[TCA_TCINDEX_HASH])
		cp.hash = nla_get_u32(tb[TCA_TCINDEX_HASH]);

	if (tb[TCA_TCINDEX_MASK])
		cp.mask = nla_get_u16(tb[TCA_TCINDEX_MASK]);

	if (tb[TCA_TCINDEX_SHIFT])
		cp.shift = nla_get_u32(tb[TCA_TCINDEX_SHIFT]);

	err = -EBUSY;
	/* Hash already allocated, make sure that we still meet the
	 * requirements for the allocated hash.
	 */
	if (cp.perfect) {
		if (!valid_perfect_hash(&cp) ||
		    cp.hash > cp.alloc_hash)
			goto errout;
	} else if (cp.h && cp.hash != cp.alloc_hash)
		goto errout;

	err = -EINVAL;
	if (tb[TCA_TCINDEX_FALL_THROUGH])
		cp.fall_through = nla_get_u32(tb[TCA_TCINDEX_FALL_THROUGH]);

	if (!cp.hash) {
		/* Hash not specified, use perfect hash if the upper limit
		 * of the hashing index is below the threshold.
		 */
		if ((cp.mask >> cp.shift) < PERFECT_HASH_THRESHOLD)
			cp.hash = (cp.mask >> cp.shift)+1;
		else
			cp.hash = DEFAULT_HASH_SIZE;
	}

	if (!cp.perfect && !cp.h)
		cp.alloc_hash = cp.hash;

	/* Note: this could be as restrictive as if (handle & ~(mask >> shift))
	 * but then, we'd fail handles that may become valid after some future
	 * mask change. While this is extremely unlikely to ever matter,
	 * the check below is safer (and also more backwards-compatible).
	 */
	if (cp.perfect || valid_perfect_hash(&cp))
		if (handle >= cp.alloc_hash)
			goto errout;


	err = -ENOMEM;
	if (!cp.perfect && !cp.h) {
		if (valid_perfect_hash(&cp)) {
			cp.perfect = kcalloc(cp.hash, sizeof(*r), GFP_KERNEL);
			if (!cp.perfect)
				goto errout;
			balloc = 1;
		} else {
			cp.h = kcalloc(cp.hash, sizeof(f), GFP_KERNEL);
			if (!cp.h)
				goto errout;
			balloc = 2;
		}
	}

	if (cp.perfect)
		r = cp.perfect + handle;
	else
		r = tcindex_lookup(&cp, handle) ? : &new_filter_result;

	if (r == &new_filter_result) {
		f = kzalloc(sizeof(*f), GFP_KERNEL);
		if (!f)
			goto errout_alloc;
	}

	if (tb[TCA_TCINDEX_CLASSID]) {
		cr.res.classid = nla_get_u32(tb[TCA_TCINDEX_CLASSID]);
		tcf_bind_filter(tp, &cr.res, base);
	}

	tcf_exts_change(tp, &cr.exts, &e);

	tcf_tree_lock(tp);
	if (old_r && old_r != r)
		memset(old_r, 0, sizeof(*old_r));

	memcpy(p, &cp, sizeof(cp));
	memcpy(r, &cr, sizeof(cr));

	if (r == &new_filter_result) {
		struct tcindex_filter **fp;

		f->key = handle;
		f->result = new_filter_result;
		f->next = NULL;
		for (fp = p->h+(handle % p->hash); *fp; fp = &(*fp)->next)
			/* nothing */;
		*fp = f;
	}
	tcf_tree_unlock(tp);

	return 0;

errout_alloc:
	if (balloc == 1)
		kfree(cp.perfect);
	else if (balloc == 2)
		kfree(cp.h);
errout:
	tcf_exts_destroy(tp, &e);
	return err;
}

static int
tcindex_change(struct tcf_proto *tp, unsigned long base, u32 handle,
	       struct nlattr **tca, unsigned long *arg)
{
	struct nlattr *opt = tca[TCA_OPTIONS];
	struct nlattr *tb[TCA_TCINDEX_MAX + 1];
	struct tcindex_data *p = PRIV(tp);
	struct tcindex_filter_result *r = (struct tcindex_filter_result *) *arg;
	int err;

	pr_debug("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p,"
	    "p %p,r %p,*arg 0x%lx\n",
	    tp, handle, tca, arg, opt, p, r, arg ? *arg : 0L);

	if (!opt)
		return 0;

	err = nla_parse_nested(tb, TCA_TCINDEX_MAX, opt, tcindex_policy);
	if (err < 0)
		return err;

	return tcindex_set_parms(tp, base, handle, p, r, tb, tca[TCA_RATE]);
}


static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker)
{
	struct tcindex_data *p = PRIV(tp);
	struct tcindex_filter *f, *next;
	int i;

	pr_debug("tcindex_walk(tp %p,walker %p),p %p\n", tp, walker, p);
	if (p->perfect) {
		for (i = 0; i < p->hash; i++) {
			if (!p->perfect[i].res.class)
				continue;
			if (walker->count >= walker->skip) {
				if (walker->fn(tp,
				    (unsigned long) (p->perfect+i), walker)
				     < 0) {
					walker->stop = 1;
					return;
				}
			}
			walker->count++;
		}
	}
	if (!p->h)
		return;
	for (i = 0; i < p->hash; i++) {
		for (f = p->h[i]; f; f = next) {
			next = f->next;
			if (walker->count >= walker->skip) {
				if (walker->fn(tp, (unsigned long) &f->result,
				    walker) < 0) {
					walker->stop = 1;
					return;
				}
			}
			walker->count++;
		}
	}
}


static int tcindex_destroy_element(struct tcf_proto *tp,
    unsigned long arg, struct tcf_walker *walker)
{
	return __tcindex_delete(tp, arg, 0);
}


static void tcindex_destroy(struct tcf_proto *tp)
{
	struct tcindex_data *p = PRIV(tp);
	struct tcf_walker walker;

	pr_debug("tcindex_destroy(tp %p),p %p\n", tp, p);
	walker.count = 0;
	walker.skip = 0;
	walker.fn = &tcindex_destroy_element;
	tcindex_walk(tp, &walker);
	kfree(p->perfect);
	kfree(p->h);
	kfree(p);
	tp->root = NULL;
}


static int tcindex_dump(struct tcf_proto *tp, unsigned long fh,
    struct sk_buff *skb, struct tcmsg *t)
{
	struct tcindex_data *p = PRIV(tp);
	struct tcindex_filter_result *r = (struct tcindex_filter_result *) fh;
	unsigned char *b = skb_tail_pointer(skb);
	struct nlattr *nest;

	pr_debug("tcindex_dump(tp %p,fh 0x%lx,skb %p,t %p),p %p,r %p,b %p\n",
		 tp, fh, skb, t, p, r, b);
	pr_debug("p->perfect %p p->h %p\n", p->perfect, p->h);

	nest = nla_nest_start(skb, TCA_OPTIONS);
	if (nest == NULL)
		goto nla_put_failure;

	if (!fh) {
		t->tcm_handle = ~0; /* whatever ... */
		NLA_PUT_U32(skb, TCA_TCINDEX_HASH, p->hash);
		NLA_PUT_U16(skb, TCA_TCINDEX_MASK, p->mask);
		NLA_PUT_U32(skb, TCA_TCINDEX_SHIFT, p->shift);
		NLA_PUT_U32(skb, TCA_TCINDEX_FALL_THROUGH, p->fall_through);
		nla_nest_end(skb, nest);
	} else {
		if (p->perfect) {
			t->tcm_handle = r-p->perfect;
		} else {
			struct tcindex_filter *f;
			int i;

			t->tcm_handle = 0;
			for (i = 0; !t->tcm_handle && i < p->hash; i++) {
				for (f = p->h[i]; !t->tcm_handle && f;
				     f = f->next) {
					if (&f->result == r)
						t->tcm_handle = f->key;
				}
			}
		}
		pr_debug("handle = %d\n", t->tcm_handle);
		if (r->res.class)
			NLA_PUT_U32(skb, TCA_TCINDEX_CLASSID, r->res.classid);

		if (tcf_exts_dump(skb, &r->exts, &tcindex_ext_map) < 0)
			goto nla_put_failure;
		nla_nest_end(skb, nest);

		if (tcf_exts_dump_stats(skb, &r->exts, &tcindex_ext_map) < 0)
			goto nla_put_failure;
	}

	return skb->len;

nla_put_failure:
	nlmsg_trim(skb, b);
	return -1;
}

static struct tcf_proto_ops cls_tcindex_ops __read_mostly = {
	.kind		=	"tcindex",
	.classify	=	tcindex_classify,
	.init		=	tcindex_init,
	.destroy	=	tcindex_destroy,
	.get		=	tcindex_get,
	.put		=	tcindex_put,
	.change		=	tcindex_change,
	.delete		=	tcindex_delete,
	.walk		=	tcindex_walk,
	.dump		=	tcindex_dump,
	.owner		=	THIS_MODULE,
};

static int __init init_tcindex(void)
{
	return register_tcf_proto_ops(&cls_tcindex_ops);
}

static void __exit exit_tcindex(void)
{
	unregister_tcf_proto_ops(&cls_tcindex_ops);
}

module_init(init_tcindex)
module_exit(exit_tcindex)
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* net/sched/cls_tcindex.c Packet classifier for skb->tc_index
	3	*
	4	* Written 1998,1999 by Werner Almesberger, EPFL ICA
	5	*/
	6
1da177e4 LT	7	#include <linux/module.h>
	8	#include <linux/types.h>
	9	#include <linux/kernel.h>
	10	#include <linux/skbuff.h>
	11	#include <linux/errno.h>
1da177e4	12	#include <net/act_api.h>
dc5fc579	13	#include <net/netlink.h>
1da177e4	14	#include <net/pkt_cls.h>
1da177e4 LT	15
	16
	17	/*
	18	* Not quite sure if we need all the xchgs Alexey uses when accessing things.
	19	* Can always add them later ... :)
	20	*/
	21
	22	/*
	23	* Passing parameters to the root seems to be done more awkwardly than really
	24	* necessary. At least, u32 doesn't seem to use such dirty hacks. To be
	25	* verified. FIXME.
	26	*/
	27
	28	#define PERFECT_HASH_THRESHOLD 64 /* use perfect hash if not bigger */
	29	#define DEFAULT_HASH_SIZE 64 /* optimized for diffserv */
	30
	31
1da177e4 LT	32	#define PRIV(tp) ((struct tcindex_data *) (tp)->root)
	33
	34
	35	struct tcindex_filter_result {
	36	struct tcf_exts exts;
	37	struct tcf_result res;
	38	};
	39
	40	struct tcindex_filter {
	41	u16 key;
	42	struct tcindex_filter_result result;
	43	struct tcindex_filter *next;
	44	};
	45
	46
	47	struct tcindex_data {
	48	struct tcindex_filter_result perfect; / perfect hash; NULL if none */
	49	struct tcindex_filter *h; / imperfect hash; only used if !perfect;
	50	NULL if unused */
	51	u16 mask; /* AND key with mask */
	52	int shift; /* shift ANDed key to the right */
	53	int hash; /* hash table size; 0 if undefined */
	54	int alloc_hash; /* allocated size */
	55	int fall_through; /* 0: only classify if explicit match */
	56	};
	57
5239008b	58	static const struct tcf_ext_map tcindex_ext_map = {
1da177e4 LT	59	.police = TCA_TCINDEX_POLICE,
	60	.action = TCA_TCINDEX_ACT
	61	};
	62
	63	static inline int
	64	tcindex_filter_is_set(struct tcindex_filter_result *r)
	65	{
	66	return tcf_exts_is_predicative(&r->exts) \|\| r->res.classid;
	67	}
	68
	69	static struct tcindex_filter_result *
	70	tcindex_lookup(struct tcindex_data *p, u16 key)
	71	{
	72	struct tcindex_filter *f;
	73
	74	if (p->perfect)
	75	return tcindex_filter_is_set(p->perfect + key) ?
	76	p->perfect + key : NULL;
	77	else if (p->h) {
	78	for (f = p->h[key % p->hash]; f; f = f->next)
	79	if (f->key == key)
	80	return &f->result;
	81	}
	82
	83	return NULL;
	84	}
	85
	86
	87	static int tcindex_classify(struct sk_buff skb, struct tcf_proto tp,
	88	struct tcf_result *res)
	89	{
	90	struct tcindex_data *p = PRIV(tp);
	91	struct tcindex_filter_result *f;
	92	int key = (skb->tc_index & p->mask) >> p->shift;
	93
aa767bfe SH	94	pr_debug("tcindex_classify(skb %p,tp %p,res %p),p %p\n",
aa767bfe SH	95	skb, tp, res, p);
1da177e4 LT	96
	97	f = tcindex_lookup(p, key);
	98	if (!f) {
	99	if (!p->fall_through)
	100	return -1;
	101	res->classid = TC_H_MAKE(TC_H_MAJ(tp->q->handle), key);
	102	res->class = 0;
aa767bfe	103	pr_debug("alg 0x%x\n", res->classid);
1da177e4 LT	104	return 0;
	105	}
	106	*res = f->res;
aa767bfe	107	pr_debug("map 0x%x\n", res->classid);
1da177e4 LT	108
	109	return tcf_exts_exec(skb, &f->exts, res);
	110	}
	111
	112
	113	static unsigned long tcindex_get(struct tcf_proto *tp, u32 handle)
	114	{
	115	struct tcindex_data *p = PRIV(tp);
	116	struct tcindex_filter_result *r;
	117
aa767bfe	118	pr_debug("tcindex_get(tp %p,handle 0x%08x)\n", tp, handle);
1da177e4 LT	119	if (p->perfect && handle >= p->alloc_hash)
	120	return 0;
	121	r = tcindex_lookup(p, handle);
	122	return r && tcindex_filter_is_set(r) ? (unsigned long) r : 0UL;
	123	}
	124
	125
	126	static void tcindex_put(struct tcf_proto *tp, unsigned long f)
	127	{
aa767bfe	128	pr_debug("tcindex_put(tp %p,f 0x%lx)\n", tp, f);
1da177e4 LT	129	}
	130
	131
	132	static int tcindex_init(struct tcf_proto *tp)
	133	{
	134	struct tcindex_data *p;
	135
aa767bfe SH	136	pr_debug("tcindex_init(tp %p)\n", tp);
aa767bfe SH	137	p = kzalloc(sizeof(struct tcindex_data), GFP_KERNEL);
1da177e4 LT	138	if (!p)
	139	return -ENOMEM;
	140
1da177e4 LT	141	p->mask = 0xffff;
	142	p->hash = DEFAULT_HASH_SIZE;
	143	p->fall_through = 1;
	144
	145	tp->root = p;
	146	return 0;
	147	}
	148
	149
	150	static int
	151	__tcindex_delete(struct tcf_proto *tp, unsigned long arg, int lock)
	152	{
	153	struct tcindex_data *p = PRIV(tp);
	154	struct tcindex_filter_result r = (struct tcindex_filter_result ) arg;
	155	struct tcindex_filter *f = NULL;
	156
aa767bfe	157	pr_debug("tcindex_delete(tp %p,arg 0x%lx),p %p,f %p\n", tp, arg, p, f);
1da177e4 LT	158	if (p->perfect) {
	159	if (!r->res.class)
	160	return -ENOENT;
	161	} else {
	162	int i;
	163	struct tcindex_filter **walk = NULL;
	164
	165	for (i = 0; i < p->hash; i++)
	166	for (walk = p->h+i; walk; walk = &(walk)->next)
	167	if (&(*walk)->result == r)
	168	goto found;
	169	return -ENOENT;
	170
	171	found:
	172	f = *walk;
	173	if (lock)
	174	tcf_tree_lock(tp);
	175	*walk = f->next;
	176	if (lock)
	177	tcf_tree_unlock(tp);
	178	}
	179	tcf_unbind_filter(tp, &r->res);
	180	tcf_exts_destroy(tp, &r->exts);
a51482bd	181	kfree(f);
1da177e4 LT	182	return 0;
	183	}
	184
	185	static int tcindex_delete(struct tcf_proto *tp, unsigned long arg)
	186	{
	187	return __tcindex_delete(tp, arg, 1);
	188	}
	189
	190	static inline int
	191	valid_perfect_hash(struct tcindex_data *p)
	192	{
	193	return p->hash > (p->mask >> p->shift);
	194	}
	195
6fa8c014 PM	196	static const struct nla_policy tcindex_policy[TCA_TCINDEX_MAX + 1] = {
	197	[TCA_TCINDEX_HASH] = { .type = NLA_U32 },
	198	[TCA_TCINDEX_MASK] = { .type = NLA_U16 },
	199	[TCA_TCINDEX_SHIFT] = { .type = NLA_U32 },
	200	[TCA_TCINDEX_FALL_THROUGH] = { .type = NLA_U32 },
	201	[TCA_TCINDEX_CLASSID] = { .type = NLA_U32 },
	202	};
	203
1da177e4 LT	204	static int
	205	tcindex_set_parms(struct tcf_proto *tp, unsigned long base, u32 handle,
	206	struct tcindex_data p, struct tcindex_filter_result r,
add93b61	207	struct nlattr *tb, struct nlattr est)
1da177e4 LT	208	{
	209	int err, balloc = 0;
	210	struct tcindex_filter_result new_filter_result, *old_r = r;
	211	struct tcindex_filter_result cr;
	212	struct tcindex_data cp;
	213	struct tcindex_filter f = NULL; / make gcc behave */
	214	struct tcf_exts e;
	215
	216	err = tcf_exts_validate(tp, tb, est, &e, &tcindex_ext_map);
	217	if (err < 0)
	218	return err;
10297b99	219
1da177e4 LT	220	memcpy(&cp, p, sizeof(cp));
	221	memset(&new_filter_result, 0, sizeof(new_filter_result));
	222
	223	if (old_r)
	224	memcpy(&cr, r, sizeof(cr));
	225	else
	226	memset(&cr, 0, sizeof(cr));
	227
6fa8c014	228	if (tb[TCA_TCINDEX_HASH])
1587bac4	229	cp.hash = nla_get_u32(tb[TCA_TCINDEX_HASH]);
1da177e4	230
6fa8c014	231	if (tb[TCA_TCINDEX_MASK])
1587bac4	232	cp.mask = nla_get_u16(tb[TCA_TCINDEX_MASK]);
1da177e4	233
6fa8c014	234	if (tb[TCA_TCINDEX_SHIFT])
1587bac4	235	cp.shift = nla_get_u32(tb[TCA_TCINDEX_SHIFT]);
1da177e4 LT	236
	237	err = -EBUSY;
	238	/* Hash already allocated, make sure that we still meet the
	239	* requirements for the allocated hash.
	240	*/
	241	if (cp.perfect) {
	242	if (!valid_perfect_hash(&cp) \|\|
	243	cp.hash > cp.alloc_hash)
	244	goto errout;
	245	} else if (cp.h && cp.hash != cp.alloc_hash)
	246	goto errout;
	247
	248	err = -EINVAL;
6fa8c014	249	if (tb[TCA_TCINDEX_FALL_THROUGH])
1587bac4	250	cp.fall_through = nla_get_u32(tb[TCA_TCINDEX_FALL_THROUGH]);
1da177e4 LT	251
	252	if (!cp.hash) {
	253	/* Hash not specified, use perfect hash if the upper limit
	254	* of the hashing index is below the threshold.
	255	*/
	256	if ((cp.mask >> cp.shift) < PERFECT_HASH_THRESHOLD)
	257	cp.hash = (cp.mask >> cp.shift)+1;
	258	else
	259	cp.hash = DEFAULT_HASH_SIZE;
	260	}
	261
	262	if (!cp.perfect && !cp.h)
	263	cp.alloc_hash = cp.hash;
	264
	265	/* Note: this could be as restrictive as if (handle & ~(mask >> shift))
	266	* but then, we'd fail handles that may become valid after some future
	267	* mask change. While this is extremely unlikely to ever matter,
	268	* the check below is safer (and also more backwards-compatible).
	269	*/
	270	if (cp.perfect \|\| valid_perfect_hash(&cp))
	271	if (handle >= cp.alloc_hash)
	272	goto errout;
	273
	274
	275	err = -ENOMEM;
	276	if (!cp.perfect && !cp.h) {
	277	if (valid_perfect_hash(&cp)) {
0da974f4	278	cp.perfect = kcalloc(cp.hash, sizeof(*r), GFP_KERNEL);
1da177e4 LT	279	if (!cp.perfect)
1da177e4 LT	280	goto errout;
1da177e4 LT	281	balloc = 1;
1da177e4 LT	282	} else {
0da974f4	283	cp.h = kcalloc(cp.hash, sizeof(f), GFP_KERNEL);
1da177e4 LT	284	if (!cp.h)
1da177e4 LT	285	goto errout;
1da177e4 LT	286	balloc = 2;
	287	}
	288	}
	289
	290	if (cp.perfect)
	291	r = cp.perfect + handle;
	292	else
	293	r = tcindex_lookup(&cp, handle) ? : &new_filter_result;
	294
	295	if (r == &new_filter_result) {
0da974f4	296	f = kzalloc(sizeof(*f), GFP_KERNEL);
1da177e4 LT	297	if (!f)
1da177e4 LT	298	goto errout_alloc;
10297b99	299	}
1da177e4	300
add93b61	301	if (tb[TCA_TCINDEX_CLASSID]) {
1587bac4	302	cr.res.classid = nla_get_u32(tb[TCA_TCINDEX_CLASSID]);
1da177e4	303	tcf_bind_filter(tp, &cr.res, base);
10297b99	304	}
1da177e4 LT	305
	306	tcf_exts_change(tp, &cr.exts, &e);
	307
	308	tcf_tree_lock(tp);
	309	if (old_r && old_r != r)
	310	memset(old_r, 0, sizeof(*old_r));
	311
	312	memcpy(p, &cp, sizeof(cp));
	313	memcpy(r, &cr, sizeof(cr));
	314
	315	if (r == &new_filter_result) {
	316	struct tcindex_filter **fp;
	317
	318	f->key = handle;
	319	f->result = new_filter_result;
	320	f->next = NULL;
	321	for (fp = p->h+(handle % p->hash); fp; fp = &(fp)->next)
	322	/* nothing */;
	323	*fp = f;
10297b99	324	}
1da177e4 LT	325	tcf_tree_unlock(tp);
	326
	327	return 0;
	328
	329	errout_alloc:
	330	if (balloc == 1)
	331	kfree(cp.perfect);
	332	else if (balloc == 2)
	333	kfree(cp.h);
	334	errout:
	335	tcf_exts_destroy(tp, &e);
	336	return err;
	337	}
	338
	339	static int
	340	tcindex_change(struct tcf_proto *tp, unsigned long base, u32 handle,
add93b61	341	struct nlattr *tca, unsigned long arg)
1da177e4	342	{
add93b61 PM	343	struct nlattr *opt = tca[TCA_OPTIONS];
add93b61 PM	344	struct nlattr *tb[TCA_TCINDEX_MAX + 1];
1da177e4 LT	345	struct tcindex_data *p = PRIV(tp);
1da177e4 LT	346	struct tcindex_filter_result r = (struct tcindex_filter_result ) *arg;
cee63723	347	int err;
1da177e4	348
aa767bfe	349	pr_debug("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p,"
1da177e4 LT	350	"p %p,r %p,*arg 0x%lx\n",
	351	tp, handle, tca, arg, opt, p, r, arg ? *arg : 0L);
	352
	353	if (!opt)
	354	return 0;
	355
6fa8c014	356	err = nla_parse_nested(tb, TCA_TCINDEX_MAX, opt, tcindex_policy);
cee63723 PM	357	if (err < 0)
cee63723 PM	358	return err;
1da177e4	359
add93b61	360	return tcindex_set_parms(tp, base, handle, p, r, tb, tca[TCA_RATE]);
1da177e4 LT	361	}
	362
	363
	364	static void tcindex_walk(struct tcf_proto tp, struct tcf_walker walker)
	365	{
	366	struct tcindex_data *p = PRIV(tp);
aa767bfe	367	struct tcindex_filter f, next;
1da177e4 LT	368	int i;
1da177e4 LT	369
aa767bfe	370	pr_debug("tcindex_walk(tp %p,walker %p),p %p\n", tp, walker, p);
1da177e4 LT	371	if (p->perfect) {
	372	for (i = 0; i < p->hash; i++) {
	373	if (!p->perfect[i].res.class)
	374	continue;
	375	if (walker->count >= walker->skip) {
	376	if (walker->fn(tp,
	377	(unsigned long) (p->perfect+i), walker)
	378	< 0) {
	379	walker->stop = 1;
	380	return;
	381	}
	382	}
	383	walker->count++;
	384	}
	385	}
	386	if (!p->h)
	387	return;
	388	for (i = 0; i < p->hash; i++) {
	389	for (f = p->h[i]; f; f = next) {
	390	next = f->next;
	391	if (walker->count >= walker->skip) {
aa767bfe	392	if (walker->fn(tp, (unsigned long) &f->result,
1da177e4 LT	393	walker) < 0) {
	394	walker->stop = 1;
	395	return;
	396	}
	397	}
	398	walker->count++;
	399	}
	400	}
	401	}
	402
	403
	404	static int tcindex_destroy_element(struct tcf_proto *tp,
	405	unsigned long arg, struct tcf_walker *walker)
	406	{
	407	return __tcindex_delete(tp, arg, 0);
	408	}
	409
	410
	411	static void tcindex_destroy(struct tcf_proto *tp)
	412	{
	413	struct tcindex_data *p = PRIV(tp);
	414	struct tcf_walker walker;
	415
aa767bfe	416	pr_debug("tcindex_destroy(tp %p),p %p\n", tp, p);
1da177e4 LT	417	walker.count = 0;
	418	walker.skip = 0;
	419	walker.fn = &tcindex_destroy_element;
aa767bfe	420	tcindex_walk(tp, &walker);
a51482bd JJ	421	kfree(p->perfect);
a51482bd JJ	422	kfree(p->h);
1da177e4 LT	423	kfree(p);
	424	tp->root = NULL;
	425	}
	426
	427
	428	static int tcindex_dump(struct tcf_proto *tp, unsigned long fh,
	429	struct sk_buff skb, struct tcmsg t)
	430	{
	431	struct tcindex_data *p = PRIV(tp);
	432	struct tcindex_filter_result r = (struct tcindex_filter_result ) fh;
27a884dc	433	unsigned char *b = skb_tail_pointer(skb);
4b3550ef	434	struct nlattr *nest;
1da177e4	435
aa767bfe SH	436	pr_debug("tcindex_dump(tp %p,fh 0x%lx,skb %p,t %p),p %p,r %p,b %p\n",
	437	tp, fh, skb, t, p, r, b);
	438	pr_debug("p->perfect %p p->h %p\n", p->perfect, p->h);
4b3550ef PM	439
	440	nest = nla_nest_start(skb, TCA_OPTIONS);
	441	if (nest == NULL)
	442	goto nla_put_failure;
	443
1da177e4 LT	444	if (!fh) {
1da177e4 LT	445	t->tcm_handle = ~0; /* whatever ... */
24beeab5 PM	446	NLA_PUT_U32(skb, TCA_TCINDEX_HASH, p->hash);
	447	NLA_PUT_U16(skb, TCA_TCINDEX_MASK, p->mask);
	448	NLA_PUT_U32(skb, TCA_TCINDEX_SHIFT, p->shift);
	449	NLA_PUT_U32(skb, TCA_TCINDEX_FALL_THROUGH, p->fall_through);
4b3550ef	450	nla_nest_end(skb, nest);
1da177e4 LT	451	} else {
	452	if (p->perfect) {
	453	t->tcm_handle = r-p->perfect;
	454	} else {
	455	struct tcindex_filter *f;
	456	int i;
	457
	458	t->tcm_handle = 0;
	459	for (i = 0; !t->tcm_handle && i < p->hash; i++) {
	460	for (f = p->h[i]; !t->tcm_handle && f;
	461	f = f->next) {
	462	if (&f->result == r)
	463	t->tcm_handle = f->key;
	464	}
	465	}
	466	}
aa767bfe	467	pr_debug("handle = %d\n", t->tcm_handle);
1da177e4	468	if (r->res.class)
24beeab5	469	NLA_PUT_U32(skb, TCA_TCINDEX_CLASSID, r->res.classid);
1da177e4 LT	470
1da177e4 LT	471	if (tcf_exts_dump(skb, &r->exts, &tcindex_ext_map) < 0)
add93b61	472	goto nla_put_failure;
4b3550ef	473	nla_nest_end(skb, nest);
1da177e4 LT	474
1da177e4 LT	475	if (tcf_exts_dump_stats(skb, &r->exts, &tcindex_ext_map) < 0)
add93b61	476	goto nla_put_failure;
1da177e4	477	}
10297b99	478
1da177e4 LT	479	return skb->len;
1da177e4 LT	480
add93b61	481	nla_put_failure:
dc5fc579	482	nlmsg_trim(skb, b);
1da177e4 LT	483	return -1;
	484	}
	485
2eb9d75c	486	static struct tcf_proto_ops cls_tcindex_ops __read_mostly = {
1da177e4 LT	487	.kind = "tcindex",
	488	.classify = tcindex_classify,
	489	.init = tcindex_init,
	490	.destroy = tcindex_destroy,
	491	.get = tcindex_get,
	492	.put = tcindex_put,
	493	.change = tcindex_change,
	494	.delete = tcindex_delete,
	495	.walk = tcindex_walk,
	496	.dump = tcindex_dump,
	497	.owner = THIS_MODULE,
	498	};
	499
	500	static int __init init_tcindex(void)
	501	{
	502	return register_tcf_proto_ops(&cls_tcindex_ops);
	503	}
	504
10297b99	505	static void __exit exit_tcindex(void)
1da177e4 LT	506	{
	507	unregister_tcf_proto_ops(&cls_tcindex_ops);
	508	}
	509
	510	module_init(init_tcindex)
	511	module_exit(exit_tcindex)
	512	MODULE_LICENSE("GPL");