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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 00000000000..404d9d83a7f
--- /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");