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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/sched/cls_tcindex.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
Diffstat (limited to 'net/sched/cls_tcindex.c')
-rw-r--r--net/sched/cls_tcindex.c537
1 files changed, 537 insertions, 0 deletions
diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c
new file mode 100644
index 000000000000..404d9d83a7fa
--- /dev/null
+++ b/net/sched/cls_tcindex.c
@@ -0,0 +1,537 @@
+/*
+ * net/sched/cls_tcindex.c	Packet classifier for skb->tc_index
+ *
+ * Written 1998,1999 by Werner Almesberger, EPFL ICA
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/skbuff.h>
+#include <linux/errno.h>
+#include <linux/netdevice.h>
+#include <net/ip.h>
+#include <net/act_api.h>
+#include <net/pkt_cls.h>
+#include <net/route.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 */
+
+
+#if 1 /* control */
+#define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
+#else
+#define DPRINTK(format,args...)
+#endif
+
+#if 0 /* data */
+#define D2PRINTK(format,args...) printk(KERN_DEBUG format,##args)
+#else
+#define D2PRINTK(format,args...)
+#endif
+
+
+#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 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;
+
+	D2PRINTK("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;
+		D2PRINTK("alg 0x%x\n",res->classid);
+		return 0;
+	}
+	*res = f->res;
+	D2PRINTK("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;
+
+	DPRINTK("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)
+{
+	DPRINTK("tcindex_put(tp %p,f 0x%lx)\n",tp,f);
+}
+
+
+static int tcindex_init(struct tcf_proto *tp)
+{
+	struct tcindex_data *p;
+
+	DPRINTK("tcindex_init(tp %p)\n",tp);
+	p = kmalloc(sizeof(struct tcindex_data),GFP_KERNEL);
+	if (!p)
+		return -ENOMEM;
+
+	memset(p, 0, sizeof(*p));
+	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;
+
+	DPRINTK("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);
+	if (f)
+		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 int
+tcindex_set_parms(struct tcf_proto *tp, unsigned long base, u32 handle,
+		  struct tcindex_data *p, struct tcindex_filter_result *r,
+		  struct rtattr **tb, struct rtattr *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));
+
+	err = -EINVAL;
+	if (tb[TCA_TCINDEX_HASH-1]) {
+		if (RTA_PAYLOAD(tb[TCA_TCINDEX_HASH-1]) < sizeof(u32))
+			goto errout;
+		cp.hash = *(u32 *) RTA_DATA(tb[TCA_TCINDEX_HASH-1]);
+	}
+
+	if (tb[TCA_TCINDEX_MASK-1]) {
+		if (RTA_PAYLOAD(tb[TCA_TCINDEX_MASK-1]) < sizeof(u16))
+			goto errout;
+		cp.mask = *(u16 *) RTA_DATA(tb[TCA_TCINDEX_MASK-1]);
+	}
+
+	if (tb[TCA_TCINDEX_SHIFT-1]) {
+		if (RTA_PAYLOAD(tb[TCA_TCINDEX_SHIFT-1]) < sizeof(u16))
+			goto errout;
+		cp.shift = *(u16 *) RTA_DATA(tb[TCA_TCINDEX_SHIFT-1]);
+	}
+
+	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-1]) {
+		if (RTA_PAYLOAD(tb[TCA_TCINDEX_FALL_THROUGH-1]) < sizeof(u32))
+			goto errout;
+		cp.fall_through =
+			*(u32 *) RTA_DATA(tb[TCA_TCINDEX_FALL_THROUGH-1]);
+	}
+
+	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 = kmalloc(cp.hash * sizeof(*r), GFP_KERNEL);
+			if (!cp.perfect)
+				goto errout;
+			memset(cp.perfect, 0, cp.hash * sizeof(*r));
+			balloc = 1;
+		} else {
+			cp.h = kmalloc(cp.hash * sizeof(f), GFP_KERNEL);
+			if (!cp.h)
+				goto errout;
+			memset(cp.h, 0, cp.hash * sizeof(f));
+			balloc = 2;
+		}
+	}
+
+	if (cp.perfect)
+		r = cp.perfect + handle;
+	else
+		r = tcindex_lookup(&cp, handle) ? : &new_filter_result;
+
+	if (r == &new_filter_result) {
+		f = kmalloc(sizeof(*f), GFP_KERNEL);
+		if (!f)
+			goto errout_alloc;
+		memset(f, 0, sizeof(*f));
+ 	}
+
+	if (tb[TCA_TCINDEX_CLASSID-1]) {
+		cr.res.classid = *(u32 *) RTA_DATA(tb[TCA_TCINDEX_CLASSID-1]);
+		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 rtattr **tca, unsigned long *arg)
+{
+	struct rtattr *opt = tca[TCA_OPTIONS-1];
+	struct rtattr *tb[TCA_TCINDEX_MAX];
+	struct tcindex_data *p = PRIV(tp);
+	struct tcindex_filter_result *r = (struct tcindex_filter_result *) *arg;
+
+	DPRINTK("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;
+
+	if (rtattr_parse_nested(tb, TCA_TCINDEX_MAX, opt) < 0)
+		return -EINVAL;
+
+	return tcindex_set_parms(tp, base, handle, p, r, tb, tca[TCA_RATE-1]);
+}
+
+
+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;
+
+	DPRINTK("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;
+
+	DPRINTK("tcindex_destroy(tp %p),p %p\n",tp,p);
+	walker.count = 0;
+	walker.skip = 0;
+	walker.fn = &tcindex_destroy_element;
+	tcindex_walk(tp,&walker);
+	if (p->perfect)
+		kfree(p->perfect);
+	if (p->h)
+		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;
+	struct rtattr *rta;
+
+	DPRINTK("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);
+	DPRINTK("p->perfect %p p->h %p\n",p->perfect,p->h);
+	rta = (struct rtattr *) b;
+	RTA_PUT(skb,TCA_OPTIONS,0,NULL);
+	if (!fh) {
+		t->tcm_handle = ~0; /* whatever ... */
+		RTA_PUT(skb,TCA_TCINDEX_HASH,sizeof(p->hash),&p->hash);
+		RTA_PUT(skb,TCA_TCINDEX_MASK,sizeof(p->mask),&p->mask);
+		RTA_PUT(skb,TCA_TCINDEX_SHIFT,sizeof(p->shift),&p->shift);
+		RTA_PUT(skb,TCA_TCINDEX_FALL_THROUGH,sizeof(p->fall_through),
+		    &p->fall_through);
+		rta->rta_len = skb->tail-b;
+	} 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;
+				}
+			}
+		}
+		DPRINTK("handle = %d\n",t->tcm_handle);
+		if (r->res.class)
+			RTA_PUT(skb, TCA_TCINDEX_CLASSID, 4, &r->res.classid);
+
+		if (tcf_exts_dump(skb, &r->exts, &tcindex_ext_map) < 0)
+			goto rtattr_failure;
+		rta->rta_len = skb->tail-b;
+
+		if (tcf_exts_dump_stats(skb, &r->exts, &tcindex_ext_map) < 0)
+			goto rtattr_failure;
+	}
+	
+	return skb->len;
+
+rtattr_failure:
+	skb_trim(skb, b - skb->data);
+	return -1;
+}
+
+static struct tcf_proto_ops cls_tcindex_ops = {
+	.next		=	NULL,
+	.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");