v4.19.13 snapshot.
diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c
new file mode 100644
index 0000000..9ccc93f
--- /dev/null
+++ b/net/sched/cls_tcindex.c
@@ -0,0 +1,673 @@
+/*
+ * 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 <linux/slab.h>
+#include <net/act_api.h>
+#include <net/netlink.h>
+#include <net/pkt_cls.h>
+#include <net/sch_generic.h>
+
+/*
+ * 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 */
+
+
+struct tcindex_filter_result {
+ struct tcf_exts exts;
+ struct tcf_result res;
+ struct rcu_work rwork;
+};
+
+struct tcindex_filter {
+ u16 key;
+ struct tcindex_filter_result result;
+ struct tcindex_filter __rcu *next;
+ struct rcu_work rwork;
+};
+
+
+struct tcindex_data {
+ struct tcindex_filter_result *perfect; /* perfect hash; NULL if none */
+ struct tcindex_filter __rcu **h; /* imperfect hash; */
+ struct tcf_proto *tp;
+ u16 mask; /* AND key with mask */
+ u32 shift; /* shift ANDed key to the right */
+ u32 hash; /* hash table size; 0 if undefined */
+ u32 alloc_hash; /* allocated size */
+ u32 fall_through; /* 0: only classify if explicit match */
+ struct rcu_head rcu;
+};
+
+static inline int tcindex_filter_is_set(struct tcindex_filter_result *r)
+{
+ return tcf_exts_has_actions(&r->exts) || r->res.classid;
+}
+
+static struct tcindex_filter_result *tcindex_lookup(struct tcindex_data *p,
+ u16 key)
+{
+ if (p->perfect) {
+ struct tcindex_filter_result *f = p->perfect + key;
+
+ return tcindex_filter_is_set(f) ? f : NULL;
+ } else if (p->h) {
+ struct tcindex_filter __rcu **fp;
+ struct tcindex_filter *f;
+
+ fp = &p->h[key % p->hash];
+ for (f = rcu_dereference_bh_rtnl(*fp);
+ f;
+ fp = &f->next, f = rcu_dereference_bh_rtnl(*fp))
+ if (f->key == key)
+ return &f->result;
+ }
+
+ return NULL;
+}
+
+
+static int tcindex_classify(struct sk_buff *skb, const struct tcf_proto *tp,
+ struct tcf_result *res)
+{
+ struct tcindex_data *p = rcu_dereference_bh(tp->root);
+ 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) {
+ struct Qdisc *q = tcf_block_q(tp->chain->block);
+
+ if (!p->fall_through)
+ return -1;
+ res->classid = TC_H_MAKE(TC_H_MAJ(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 void *tcindex_get(struct tcf_proto *tp, u32 handle)
+{
+ struct tcindex_data *p = rtnl_dereference(tp->root);
+ 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 NULL;
+ r = tcindex_lookup(p, handle);
+ return r && tcindex_filter_is_set(r) ? r : NULL;
+}
+
+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;
+
+ rcu_assign_pointer(tp->root, p);
+ return 0;
+}
+
+static void __tcindex_destroy_rexts(struct tcindex_filter_result *r)
+{
+ tcf_exts_destroy(&r->exts);
+ tcf_exts_put_net(&r->exts);
+}
+
+static void tcindex_destroy_rexts_work(struct work_struct *work)
+{
+ struct tcindex_filter_result *r;
+
+ r = container_of(to_rcu_work(work),
+ struct tcindex_filter_result,
+ rwork);
+ rtnl_lock();
+ __tcindex_destroy_rexts(r);
+ rtnl_unlock();
+}
+
+static void __tcindex_destroy_fexts(struct tcindex_filter *f)
+{
+ tcf_exts_destroy(&f->result.exts);
+ tcf_exts_put_net(&f->result.exts);
+ kfree(f);
+}
+
+static void tcindex_destroy_fexts_work(struct work_struct *work)
+{
+ struct tcindex_filter *f = container_of(to_rcu_work(work),
+ struct tcindex_filter,
+ rwork);
+
+ rtnl_lock();
+ __tcindex_destroy_fexts(f);
+ rtnl_unlock();
+}
+
+static int tcindex_delete(struct tcf_proto *tp, void *arg, bool *last,
+ struct netlink_ext_ack *extack)
+{
+ struct tcindex_data *p = rtnl_dereference(tp->root);
+ struct tcindex_filter_result *r = arg;
+ struct tcindex_filter __rcu **walk;
+ struct tcindex_filter *f = NULL;
+
+ pr_debug("tcindex_delete(tp %p,arg %p),p %p\n", tp, arg, p);
+ if (p->perfect) {
+ if (!r->res.class)
+ return -ENOENT;
+ } else {
+ int i;
+
+ for (i = 0; i < p->hash; i++) {
+ walk = p->h + i;
+ for (f = rtnl_dereference(*walk); f;
+ walk = &f->next, f = rtnl_dereference(*walk)) {
+ if (&f->result == r)
+ goto found;
+ }
+ }
+ return -ENOENT;
+
+found:
+ rcu_assign_pointer(*walk, rtnl_dereference(f->next));
+ }
+ tcf_unbind_filter(tp, &r->res);
+ /* all classifiers are required to call tcf_exts_destroy() after rcu
+ * grace period, since converted-to-rcu actions are relying on that
+ * in cleanup() callback
+ */
+ if (f) {
+ if (tcf_exts_get_net(&f->result.exts))
+ tcf_queue_work(&f->rwork, tcindex_destroy_fexts_work);
+ else
+ __tcindex_destroy_fexts(f);
+ } else {
+ if (tcf_exts_get_net(&r->exts))
+ tcf_queue_work(&r->rwork, tcindex_destroy_rexts_work);
+ else
+ __tcindex_destroy_rexts(r);
+ }
+
+ *last = false;
+ return 0;
+}
+
+static int tcindex_destroy_element(struct tcf_proto *tp,
+ void *arg, struct tcf_walker *walker)
+{
+ bool last;
+
+ return tcindex_delete(tp, arg, &last, NULL);
+}
+
+static void __tcindex_destroy(struct rcu_head *head)
+{
+ struct tcindex_data *p = container_of(head, struct tcindex_data, rcu);
+
+ kfree(p->perfect);
+ kfree(p->h);
+ kfree(p);
+}
+
+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_filter_result_init(struct tcindex_filter_result *r)
+{
+ memset(r, 0, sizeof(*r));
+ return tcf_exts_init(&r->exts, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
+}
+
+static void __tcindex_partial_destroy(struct rcu_head *head)
+{
+ struct tcindex_data *p = container_of(head, struct tcindex_data, rcu);
+
+ kfree(p->perfect);
+ kfree(p);
+}
+
+static void tcindex_free_perfect_hash(struct tcindex_data *cp)
+{
+ int i;
+
+ for (i = 0; i < cp->hash; i++)
+ tcf_exts_destroy(&cp->perfect[i].exts);
+ kfree(cp->perfect);
+}
+
+static int tcindex_alloc_perfect_hash(struct tcindex_data *cp)
+{
+ int i, err = 0;
+
+ cp->perfect = kcalloc(cp->hash, sizeof(struct tcindex_filter_result),
+ GFP_KERNEL);
+ if (!cp->perfect)
+ return -ENOMEM;
+
+ for (i = 0; i < cp->hash; i++) {
+ err = tcf_exts_init(&cp->perfect[i].exts,
+ TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
+ if (err < 0)
+ goto errout;
+ }
+
+ return 0;
+
+errout:
+ tcindex_free_perfect_hash(cp);
+ return err;
+}
+
+static int
+tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
+ u32 handle, struct tcindex_data *p,
+ struct tcindex_filter_result *r, struct nlattr **tb,
+ struct nlattr *est, bool ovr, struct netlink_ext_ack *extack)
+{
+ struct tcindex_filter_result new_filter_result, *old_r = r;
+ struct tcindex_filter_result cr;
+ struct tcindex_data *cp = NULL, *oldp;
+ struct tcindex_filter *f = NULL; /* make gcc behave */
+ int err, balloc = 0;
+ struct tcf_exts e;
+
+ err = tcf_exts_init(&e, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
+ if (err < 0)
+ return err;
+ err = tcf_exts_validate(net, tp, tb, est, &e, ovr, extack);
+ if (err < 0)
+ goto errout;
+
+ err = -ENOMEM;
+ /* tcindex_data attributes must look atomic to classifier/lookup so
+ * allocate new tcindex data and RCU assign it onto root. Keeping
+ * perfect hash and hash pointers from old data.
+ */
+ cp = kzalloc(sizeof(*cp), GFP_KERNEL);
+ if (!cp)
+ goto errout;
+
+ cp->mask = p->mask;
+ cp->shift = p->shift;
+ cp->hash = p->hash;
+ cp->alloc_hash = p->alloc_hash;
+ cp->fall_through = p->fall_through;
+ cp->tp = tp;
+
+ if (p->perfect) {
+ int i;
+
+ if (tcindex_alloc_perfect_hash(cp) < 0)
+ goto errout;
+ for (i = 0; i < cp->hash; i++)
+ cp->perfect[i].res = p->perfect[i].res;
+ balloc = 1;
+ }
+ cp->h = p->h;
+
+ err = tcindex_filter_result_init(&new_filter_result);
+ if (err < 0)
+ goto errout1;
+ err = tcindex_filter_result_init(&cr);
+ if (err < 0)
+ goto errout1;
+ if (old_r)
+ cr.res = r->res;
+
+ 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_alloc;
+ } else if (cp->h && cp->hash != cp->alloc_hash) {
+ goto errout_alloc;
+ }
+
+ 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_alloc;
+
+
+ err = -ENOMEM;
+ if (!cp->perfect && !cp->h) {
+ if (valid_perfect_hash(cp)) {
+ if (tcindex_alloc_perfect_hash(cp) < 0)
+ goto errout_alloc;
+ balloc = 1;
+ } else {
+ struct tcindex_filter __rcu **hash;
+
+ hash = kcalloc(cp->hash,
+ sizeof(struct tcindex_filter *),
+ GFP_KERNEL);
+
+ if (!hash)
+ goto errout_alloc;
+
+ cp->h = hash;
+ 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;
+ f->key = handle;
+ f->next = NULL;
+ err = tcindex_filter_result_init(&f->result);
+ if (err < 0) {
+ kfree(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);
+ }
+
+ if (old_r && old_r != r) {
+ err = tcindex_filter_result_init(old_r);
+ if (err < 0) {
+ kfree(f);
+ goto errout_alloc;
+ }
+ }
+
+ oldp = p;
+ r->res = cr.res;
+ tcf_exts_change(&r->exts, &e);
+
+ rcu_assign_pointer(tp->root, cp);
+
+ if (r == &new_filter_result) {
+ struct tcindex_filter *nfp;
+ struct tcindex_filter __rcu **fp;
+
+ f->result.res = r->res;
+ tcf_exts_change(&f->result.exts, &r->exts);
+
+ fp = cp->h + (handle % cp->hash);
+ for (nfp = rtnl_dereference(*fp);
+ nfp;
+ fp = &nfp->next, nfp = rtnl_dereference(*fp))
+ ; /* nothing */
+
+ rcu_assign_pointer(*fp, f);
+ }
+
+ if (oldp)
+ call_rcu(&oldp->rcu, __tcindex_partial_destroy);
+ return 0;
+
+errout_alloc:
+ if (balloc == 1)
+ tcindex_free_perfect_hash(cp);
+ else if (balloc == 2)
+ kfree(cp->h);
+errout1:
+ tcf_exts_destroy(&cr.exts);
+ tcf_exts_destroy(&new_filter_result.exts);
+errout:
+ kfree(cp);
+ tcf_exts_destroy(&e);
+ return err;
+}
+
+static int
+tcindex_change(struct net *net, struct sk_buff *in_skb,
+ struct tcf_proto *tp, unsigned long base, u32 handle,
+ struct nlattr **tca, void **arg, bool ovr,
+ struct netlink_ext_ack *extack)
+{
+ struct nlattr *opt = tca[TCA_OPTIONS];
+ struct nlattr *tb[TCA_TCINDEX_MAX + 1];
+ struct tcindex_data *p = rtnl_dereference(tp->root);
+ struct tcindex_filter_result *r = *arg;
+ int err;
+
+ pr_debug("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p,"
+ "p %p,r %p,*arg %p\n",
+ tp, handle, tca, arg, opt, p, r, arg ? *arg : NULL);
+
+ if (!opt)
+ return 0;
+
+ err = nla_parse_nested(tb, TCA_TCINDEX_MAX, opt, tcindex_policy, NULL);
+ if (err < 0)
+ return err;
+
+ return tcindex_set_parms(net, tp, base, handle, p, r, tb,
+ tca[TCA_RATE], ovr, extack);
+}
+
+static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker)
+{
+ struct tcindex_data *p = rtnl_dereference(tp->root);
+ 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, p->perfect + i, walker) < 0) {
+ walker->stop = 1;
+ return;
+ }
+ }
+ walker->count++;
+ }
+ }
+ if (!p->h)
+ return;
+ for (i = 0; i < p->hash; i++) {
+ for (f = rtnl_dereference(p->h[i]); f; f = next) {
+ next = rtnl_dereference(f->next);
+ if (walker->count >= walker->skip) {
+ if (walker->fn(tp, &f->result, walker) < 0) {
+ walker->stop = 1;
+ return;
+ }
+ }
+ walker->count++;
+ }
+ }
+}
+
+static void tcindex_destroy(struct tcf_proto *tp,
+ struct netlink_ext_ack *extack)
+{
+ struct tcindex_data *p = rtnl_dereference(tp->root);
+ 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);
+
+ call_rcu(&p->rcu, __tcindex_destroy);
+}
+
+
+static int tcindex_dump(struct net *net, struct tcf_proto *tp, void *fh,
+ struct sk_buff *skb, struct tcmsg *t)
+{
+ struct tcindex_data *p = rtnl_dereference(tp->root);
+ struct tcindex_filter_result *r = fh;
+ struct nlattr *nest;
+
+ pr_debug("tcindex_dump(tp %p,fh %p,skb %p,t %p),p %p,r %p\n",
+ tp, fh, skb, t, p, r);
+ 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 ... */
+ if (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))
+ goto nla_put_failure;
+ nla_nest_end(skb, nest);
+ } else {
+ if (p->perfect) {
+ t->tcm_handle = r - p->perfect;
+ } else {
+ struct tcindex_filter *f;
+ struct tcindex_filter __rcu **fp;
+ int i;
+
+ t->tcm_handle = 0;
+ for (i = 0; !t->tcm_handle && i < p->hash; i++) {
+ fp = &p->h[i];
+ for (f = rtnl_dereference(*fp);
+ !t->tcm_handle && f;
+ fp = &f->next, f = rtnl_dereference(*fp)) {
+ 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))
+ goto nla_put_failure;
+
+ if (tcf_exts_dump(skb, &r->exts) < 0)
+ goto nla_put_failure;
+ nla_nest_end(skb, nest);
+
+ if (tcf_exts_dump_stats(skb, &r->exts) < 0)
+ goto nla_put_failure;
+ }
+
+ return skb->len;
+
+nla_put_failure:
+ nla_nest_cancel(skb, nest);
+ return -1;
+}
+
+static void tcindex_bind_class(void *fh, u32 classid, unsigned long cl)
+{
+ struct tcindex_filter_result *r = fh;
+
+ if (r && r->res.classid == classid)
+ r->res.class = cl;
+}
+
+static struct tcf_proto_ops cls_tcindex_ops __read_mostly = {
+ .kind = "tcindex",
+ .classify = tcindex_classify,
+ .init = tcindex_init,
+ .destroy = tcindex_destroy,
+ .get = tcindex_get,
+ .change = tcindex_change,
+ .delete = tcindex_delete,
+ .walk = tcindex_walk,
+ .dump = tcindex_dump,
+ .bind_class = tcindex_bind_class,
+ .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");