#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
+#include <linux/percpu.h>
#include <linux/rtnetlink.h>
#include <linux/skbuff.h>
#include <linux/bitmap.h>
#include <net/pkt_cls.h>
struct tc_u_knode {
- struct tc_u_knode *next;
+ struct tc_u_knode __rcu *next;
u32 handle;
- struct tc_u_hnode *ht_up;
+ struct tc_u_hnode __rcu *ht_up;
struct tcf_exts exts;
#ifdef CONFIG_NET_CLS_IND
int ifindex;
#endif
u8 fshift;
struct tcf_result res;
- struct tc_u_hnode *ht_down;
+ struct tc_u_hnode __rcu *ht_down;
#ifdef CONFIG_CLS_U32_PERF
- struct tc_u32_pcnt *pf;
+ struct tc_u32_pcnt __percpu *pf;
#endif
#ifdef CONFIG_CLS_U32_MARK
- struct tc_u32_mark mark;
+ u32 val;
+ u32 mask;
+ u32 __percpu *pcpu_success;
#endif
+ struct tcf_proto *tp;
+ struct rcu_head rcu;
+ /* The 'sel' field MUST be the last field in structure to allow for
+ * tc_u32_keys allocated at end of structure.
+ */
struct tc_u32_sel sel;
};
struct tc_u_hnode {
- struct tc_u_hnode *next;
+ struct tc_u_hnode __rcu *next;
u32 handle;
u32 prio;
struct tc_u_common *tp_c;
int refcnt;
unsigned int divisor;
- struct tc_u_knode *ht[1];
+ struct tc_u_knode __rcu *ht[1];
+ struct rcu_head rcu;
};
struct tc_u_common {
- struct tc_u_hnode *hlist;
+ struct tc_u_hnode __rcu *hlist;
struct Qdisc *q;
int refcnt;
u32 hgenerator;
+ struct rcu_head rcu;
};
static inline unsigned int u32_hash_fold(__be32 key,
unsigned int off;
} stack[TC_U32_MAXDEPTH];
- struct tc_u_hnode *ht = tp->root;
+ struct tc_u_hnode *ht = rcu_dereference_bh(tp->root);
unsigned int off = skb_network_offset(skb);
struct tc_u_knode *n;
int sdepth = 0;
int i, r;
next_ht:
- n = ht->ht[sel];
+ n = rcu_dereference_bh(ht->ht[sel]);
next_knode:
if (n) {
struct tc_u32_key *key = n->sel.keys;
#ifdef CONFIG_CLS_U32_PERF
- n->pf->rcnt += 1;
+ __this_cpu_inc(n->pf->rcnt);
j = 0;
#endif
#ifdef CONFIG_CLS_U32_MARK
- if ((skb->mark & n->mark.mask) != n->mark.val) {
- n = n->next;
+ if ((skb->mark & n->mask) != n->val) {
+ n = rcu_dereference_bh(n->next);
goto next_knode;
} else {
- n->mark.success++;
+ __this_cpu_inc(*n->pcpu_success);
}
#endif
if (!data)
goto out;
if ((*data ^ key->val) & key->mask) {
- n = n->next;
+ n = rcu_dereference_bh(n->next);
goto next_knode;
}
#ifdef CONFIG_CLS_U32_PERF
- n->pf->kcnts[j] += 1;
+ __this_cpu_inc(n->pf->kcnts[j]);
j++;
#endif
}
- if (n->ht_down == NULL) {
+
+ ht = rcu_dereference_bh(n->ht_down);
+ if (!ht) {
check_terminal:
if (n->sel.flags & TC_U32_TERMINAL) {
*res = n->res;
#ifdef CONFIG_NET_CLS_IND
if (!tcf_match_indev(skb, n->ifindex)) {
- n = n->next;
+ n = rcu_dereference_bh(n->next);
goto next_knode;
}
#endif
#ifdef CONFIG_CLS_U32_PERF
- n->pf->rhit += 1;
+ __this_cpu_inc(n->pf->rhit);
#endif
r = tcf_exts_exec(skb, &n->exts, res);
if (r < 0) {
- n = n->next;
+ n = rcu_dereference_bh(n->next);
goto next_knode;
}
return r;
}
- n = n->next;
+ n = rcu_dereference_bh(n->next);
goto next_knode;
}
stack[sdepth].off = off;
sdepth++;
- ht = n->ht_down;
+ ht = rcu_dereference_bh(n->ht_down);
sel = 0;
if (ht->divisor) {
__be32 *data, hdata;
/* POP */
if (sdepth--) {
n = stack[sdepth].knode;
- ht = n->ht_up;
+ ht = rcu_dereference_bh(n->ht_up);
off = stack[sdepth].off;
goto check_terminal;
}
{
struct tc_u_hnode *ht;
- for (ht = tp_c->hlist; ht; ht = ht->next)
+ for (ht = rtnl_dereference(tp_c->hlist);
+ ht;
+ ht = rtnl_dereference(ht->next))
if (ht->handle == handle)
break;
if (sel > ht->divisor)
goto out;
- for (n = ht->ht[sel]; n; n = n->next)
+ for (n = rtnl_dereference(ht->ht[sel]);
+ n;
+ n = rtnl_dereference(n->next))
if (n->handle == handle)
break;
out:
struct tc_u_common *tp_c = tp->data;
if (TC_U32_HTID(handle) == TC_U32_ROOT)
- ht = tp->root;
+ ht = rtnl_dereference(tp->root);
else
ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
{
int i = 0x800;
+ /* hgenerator only used inside rtnl lock it is safe to increment
+ * without read _copy_ update semantics
+ */
do {
if (++tp_c->hgenerator == 0x7FF)
tp_c->hgenerator = 1;
}
tp_c->refcnt++;
- root_ht->next = tp_c->hlist;
- tp_c->hlist = root_ht;
+ RCU_INIT_POINTER(root_ht->next, tp_c->hlist);
+ rcu_assign_pointer(tp_c->hlist, root_ht);
root_ht->tp_c = tp_c;
- tp->root = root_ht;
+ rcu_assign_pointer(tp->root, root_ht);
tp->data = tp_c;
return 0;
}
-static int u32_destroy_key(struct tcf_proto *tp, struct tc_u_knode *n)
+static int u32_destroy_key(struct tcf_proto *tp,
+ struct tc_u_knode *n,
+ bool free_pf)
{
- tcf_unbind_filter(tp, &n->res);
- tcf_exts_destroy(tp, &n->exts);
+ tcf_exts_destroy(&n->exts);
if (n->ht_down)
n->ht_down->refcnt--;
#ifdef CONFIG_CLS_U32_PERF
- kfree(n->pf);
+ if (free_pf)
+ free_percpu(n->pf);
+#endif
+#ifdef CONFIG_CLS_U32_MARK
+ if (free_pf)
+ free_percpu(n->pcpu_success);
#endif
kfree(n);
return 0;
}
+/* u32_delete_key_rcu should be called when free'ing a copied
+ * version of a tc_u_knode obtained from u32_init_knode(). When
+ * copies are obtained from u32_init_knode() the statistics are
+ * shared between the old and new copies to allow readers to
+ * continue to update the statistics during the copy. To support
+ * this the u32_delete_key_rcu variant does not free the percpu
+ * statistics.
+ */
+static void u32_delete_key_rcu(struct rcu_head *rcu)
+{
+ struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
+
+ u32_destroy_key(key->tp, key, false);
+}
+
+/* u32_delete_key_freepf_rcu is the rcu callback variant
+ * that free's the entire structure including the statistics
+ * percpu variables. Only use this if the key is not a copy
+ * returned by u32_init_knode(). See u32_delete_key_rcu()
+ * for the variant that should be used with keys return from
+ * u32_init_knode()
+ */
+static void u32_delete_key_freepf_rcu(struct rcu_head *rcu)
+{
+ struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
+
+ u32_destroy_key(key->tp, key, true);
+}
+
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;
+ struct tc_u_knode __rcu **kp;
+ struct tc_u_knode *pkp;
+ struct tc_u_hnode *ht = rtnl_dereference(key->ht_up);
if (ht) {
- for (kp = &ht->ht[TC_U32_HASH(key->handle)]; *kp; kp = &(*kp)->next) {
- if (*kp == key) {
- tcf_tree_lock(tp);
- *kp = key->next;
- tcf_tree_unlock(tp);
-
- u32_destroy_key(tp, key);
+ kp = &ht->ht[TC_U32_HASH(key->handle)];
+ for (pkp = rtnl_dereference(*kp); pkp;
+ kp = &pkp->next, pkp = rtnl_dereference(*kp)) {
+ if (pkp == key) {
+ RCU_INIT_POINTER(*kp, key->next);
+
+ tcf_unbind_filter(tp, &key->res);
+ call_rcu(&key->rcu, u32_delete_key_freepf_rcu);
return 0;
}
}
unsigned int h;
for (h = 0; h <= ht->divisor; h++) {
- while ((n = ht->ht[h]) != NULL) {
- ht->ht[h] = n->next;
-
- u32_destroy_key(tp, n);
+ while ((n = rtnl_dereference(ht->ht[h])) != NULL) {
+ RCU_INIT_POINTER(ht->ht[h],
+ rtnl_dereference(n->next));
+ tcf_unbind_filter(tp, &n->res);
+ call_rcu(&n->rcu, u32_delete_key_freepf_rcu);
}
}
}
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;
+ struct tc_u_hnode __rcu **hn;
+ struct tc_u_hnode *phn;
WARN_ON(ht->refcnt);
u32_clear_hnode(tp, ht);
- for (hn = &tp_c->hlist; *hn; hn = &(*hn)->next) {
- if (*hn == ht) {
- *hn = ht->next;
- kfree(ht);
+ hn = &tp_c->hlist;
+ for (phn = rtnl_dereference(*hn);
+ phn;
+ hn = &phn->next, phn = rtnl_dereference(*hn)) {
+ if (phn == ht) {
+ RCU_INIT_POINTER(*hn, ht->next);
+ kfree_rcu(ht, rcu);
return 0;
}
}
- WARN_ON(1);
return -ENOENT;
}
static void u32_destroy(struct tcf_proto *tp)
{
struct tc_u_common *tp_c = tp->data;
- struct tc_u_hnode *root_ht = tp->root;
+ struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
WARN_ON(root_ht == NULL);
tp->q->u32_node = NULL;
- for (ht = tp_c->hlist; ht; ht = ht->next) {
+ for (ht = rtnl_dereference(tp_c->hlist);
+ ht;
+ ht = rtnl_dereference(ht->next)) {
ht->refcnt--;
u32_clear_hnode(tp, ht);
}
- while ((ht = tp_c->hlist) != NULL) {
- tp_c->hlist = ht->next;
-
- WARN_ON(ht->refcnt != 0);
-
- kfree(ht);
+ while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) {
+ RCU_INIT_POINTER(tp_c->hlist, ht->next);
+ kfree_rcu(ht, rcu);
}
kfree(tp_c);
static int u32_delete(struct tcf_proto *tp, unsigned long arg)
{
struct tc_u_hnode *ht = (struct tc_u_hnode *)arg;
+ struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
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)
+ if (root_ht == ht)
return -EINVAL;
if (ht->refcnt == 1) {
if (!bitmap)
return handle | 0xFFF;
- for (n = ht->ht[TC_U32_HASH(handle)]; n; n = n->next)
+ for (n = rtnl_dereference(ht->ht[TC_U32_HASH(handle)]);
+ n;
+ n = rtnl_dereference(n->next))
set_bit(TC_U32_NODE(n->handle), bitmap);
i = find_next_zero_bit(bitmap, NR_U32_NODE, 0x800);
ht_down->refcnt++;
}
- tcf_tree_lock(tp);
- ht_old = n->ht_down;
- n->ht_down = ht_down;
- tcf_tree_unlock(tp);
+ ht_old = rtnl_dereference(n->ht_down);
+ rcu_assign_pointer(n->ht_down, ht_down);
if (ht_old)
ht_old->refcnt--;
return 0;
errout:
- tcf_exts_destroy(tp, &e);
+ tcf_exts_destroy(&e);
return err;
}
+static void u32_replace_knode(struct tcf_proto *tp,
+ struct tc_u_common *tp_c,
+ struct tc_u_knode *n)
+{
+ struct tc_u_knode __rcu **ins;
+ struct tc_u_knode *pins;
+ struct tc_u_hnode *ht;
+
+ if (TC_U32_HTID(n->handle) == TC_U32_ROOT)
+ ht = rtnl_dereference(tp->root);
+ else
+ ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle));
+
+ ins = &ht->ht[TC_U32_HASH(n->handle)];
+
+ /* The node must always exist for it to be replaced if this is not the
+ * case then something went very wrong elsewhere.
+ */
+ for (pins = rtnl_dereference(*ins); ;
+ ins = &pins->next, pins = rtnl_dereference(*ins))
+ if (pins->handle == n->handle)
+ break;
+
+ RCU_INIT_POINTER(n->next, pins->next);
+ rcu_assign_pointer(*ins, n);
+}
+
+static struct tc_u_knode *u32_init_knode(struct tcf_proto *tp,
+ struct tc_u_knode *n)
+{
+ struct tc_u_knode *new;
+ struct tc_u32_sel *s = &n->sel;
+
+ new = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key),
+ GFP_KERNEL);
+
+ if (!new)
+ return NULL;
+
+ RCU_INIT_POINTER(new->next, n->next);
+ new->handle = n->handle;
+ RCU_INIT_POINTER(new->ht_up, n->ht_up);
+
+#ifdef CONFIG_NET_CLS_IND
+ new->ifindex = n->ifindex;
+#endif
+ new->fshift = n->fshift;
+ new->res = n->res;
+ RCU_INIT_POINTER(new->ht_down, n->ht_down);
+
+ /* bump reference count as long as we hold pointer to structure */
+ if (new->ht_down)
+ new->ht_down->refcnt++;
+
+#ifdef CONFIG_CLS_U32_PERF
+ /* Statistics may be incremented by readers during update
+ * so we must keep them in tact. When the node is later destroyed
+ * a special destroy call must be made to not free the pf memory.
+ */
+ new->pf = n->pf;
+#endif
+
+#ifdef CONFIG_CLS_U32_MARK
+ new->val = n->val;
+ new->mask = n->mask;
+ /* Similarly success statistics must be moved as pointers */
+ new->pcpu_success = n->pcpu_success;
+#endif
+ new->tp = tp;
+ memcpy(&new->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
+
+ tcf_exts_init(&new->exts, TCA_U32_ACT, TCA_U32_POLICE);
+
+ return new;
+}
+
static int u32_change(struct net *net, struct sk_buff *in_skb,
struct tcf_proto *tp, unsigned long base, u32 handle,
struct nlattr **tca,
struct nlattr *tb[TCA_U32_MAX + 1];
u32 htid;
int err;
+#ifdef CONFIG_CLS_U32_PERF
+ size_t size;
+#endif
if (opt == NULL)
return handle ? -EINVAL : 0;
n = (struct tc_u_knode *)*arg;
if (n) {
+ struct tc_u_knode *new;
+
if (TC_U32_KEY(n->handle) == 0)
return -EINVAL;
- return u32_set_parms(net, tp, base, n->ht_up, n, tb,
- tca[TCA_RATE], ovr);
+ new = u32_init_knode(tp, n);
+ if (!new)
+ return -ENOMEM;
+
+ err = u32_set_parms(net, tp, base,
+ rtnl_dereference(n->ht_up), new, tb,
+ tca[TCA_RATE], ovr);
+
+ if (err) {
+ u32_destroy_key(tp, new, false);
+ return err;
+ }
+
+ u32_replace_knode(tp, tp_c, new);
+ tcf_unbind_filter(tp, &n->res);
+ call_rcu(&n->rcu, u32_delete_key_rcu);
+ return 0;
}
if (tb[TCA_U32_DIVISOR]) {
ht->divisor = divisor;
ht->handle = handle;
ht->prio = tp->prio;
- ht->next = tp_c->hlist;
- tp_c->hlist = ht;
+ RCU_INIT_POINTER(ht->next, tp_c->hlist);
+ rcu_assign_pointer(tp_c->hlist, ht);
*arg = (unsigned long)ht;
return 0;
}
if (tb[TCA_U32_HASH]) {
htid = nla_get_u32(tb[TCA_U32_HASH]);
if (TC_U32_HTID(htid) == TC_U32_ROOT) {
- ht = tp->root;
+ ht = rtnl_dereference(tp->root);
htid = ht->handle;
} else {
ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
return -EINVAL;
}
} else {
- ht = tp->root;
+ ht = rtnl_dereference(tp->root);
htid = ht->handle;
}
return -ENOBUFS;
#ifdef CONFIG_CLS_U32_PERF
- n->pf = kzalloc(sizeof(struct tc_u32_pcnt) + s->nkeys*sizeof(u64), GFP_KERNEL);
- if (n->pf == NULL) {
+ size = sizeof(struct tc_u32_pcnt) + s->nkeys * sizeof(u64);
+ n->pf = __alloc_percpu(size, __alignof__(struct tc_u32_pcnt));
+ if (!n->pf) {
kfree(n);
return -ENOBUFS;
}
#endif
memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
- n->ht_up = ht;
+ RCU_INIT_POINTER(n->ht_up, ht);
n->handle = handle;
n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
tcf_exts_init(&n->exts, TCA_U32_ACT, TCA_U32_POLICE);
+ n->tp = tp;
#ifdef CONFIG_CLS_U32_MARK
+ n->pcpu_success = alloc_percpu(u32);
+ if (!n->pcpu_success) {
+ err = -ENOMEM;
+ goto errout;
+ }
+
if (tb[TCA_U32_MARK]) {
struct tc_u32_mark *mark;
mark = nla_data(tb[TCA_U32_MARK]);
- memcpy(&n->mark, mark, sizeof(struct tc_u32_mark));
- n->mark.success = 0;
+ n->val = mark->val;
+ n->mask = mark->mask;
}
#endif
err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE], ovr);
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))
+ struct tc_u_knode __rcu **ins;
+ struct tc_u_knode *pins;
+
+ ins = &ht->ht[TC_U32_HASH(handle)];
+ for (pins = rtnl_dereference(*ins); pins;
+ ins = &pins->next, pins = rtnl_dereference(*ins))
+ if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle))
break;
- n->next = *ins;
- tcf_tree_lock(tp);
- *ins = n;
- tcf_tree_unlock(tp);
+ RCU_INIT_POINTER(n->next, pins);
+ rcu_assign_pointer(*ins, n);
*arg = (unsigned long)n;
return 0;
}
+
+#ifdef CONFIG_CLS_U32_MARK
+ free_percpu(n->pcpu_success);
+errout:
+#endif
+
#ifdef CONFIG_CLS_U32_PERF
- kfree(n->pf);
+ free_percpu(n->pf);
#endif
kfree(n);
return err;
if (arg->stop)
return;
- for (ht = tp_c->hlist; ht; ht = ht->next) {
+ for (ht = rtnl_dereference(tp_c->hlist);
+ ht;
+ ht = rtnl_dereference(ht->next)) {
if (ht->prio != tp->prio)
continue;
if (arg->count >= arg->skip) {
}
arg->count++;
for (h = 0; h <= ht->divisor; h++) {
- for (n = ht->ht[h]; n; n = n->next) {
+ for (n = rtnl_dereference(ht->ht[h]);
+ n;
+ n = rtnl_dereference(n->next)) {
if (arg->count < arg->skip) {
arg->count++;
continue;
struct sk_buff *skb, struct tcmsg *t)
{
struct tc_u_knode *n = (struct tc_u_knode *)fh;
+ struct tc_u_hnode *ht_up, *ht_down;
struct nlattr *nest;
if (n == NULL)
if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
goto nla_put_failure;
} else {
+#ifdef CONFIG_CLS_U32_PERF
+ struct tc_u32_pcnt *gpf;
+ int cpu;
+#endif
+
if (nla_put(skb, TCA_U32_SEL,
sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
&n->sel))
goto nla_put_failure;
- if (n->ht_up) {
+
+ ht_up = rtnl_dereference(n->ht_up);
+ if (ht_up) {
u32 htid = n->handle & 0xFFFFF000;
if (nla_put_u32(skb, TCA_U32_HASH, htid))
goto nla_put_failure;
if (n->res.classid &&
nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
goto nla_put_failure;
- if (n->ht_down &&
- nla_put_u32(skb, TCA_U32_LINK, n->ht_down->handle))
+
+ ht_down = rtnl_dereference(n->ht_down);
+ if (ht_down &&
+ nla_put_u32(skb, TCA_U32_LINK, ht_down->handle))
goto nla_put_failure;
#ifdef CONFIG_CLS_U32_MARK
- if ((n->mark.val || n->mark.mask) &&
- nla_put(skb, TCA_U32_MARK, sizeof(n->mark), &n->mark))
- goto nla_put_failure;
+ if ((n->val || n->mask)) {
+ struct tc_u32_mark mark = {.val = n->val,
+ .mask = n->mask,
+ .success = 0};
+ int cpum;
+
+ for_each_possible_cpu(cpum) {
+ __u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum);
+
+ mark.success += cnt;
+ }
+
+ if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark))
+ goto nla_put_failure;
+ }
#endif
if (tcf_exts_dump(skb, &n->exts) < 0)
}
#endif
#ifdef CONFIG_CLS_U32_PERF
+ gpf = kzalloc(sizeof(struct tc_u32_pcnt) +
+ n->sel.nkeys * sizeof(u64),
+ GFP_KERNEL);
+ if (!gpf)
+ goto nla_put_failure;
+
+ for_each_possible_cpu(cpu) {
+ int i;
+ struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu);
+
+ gpf->rcnt += pf->rcnt;
+ gpf->rhit += pf->rhit;
+ for (i = 0; i < n->sel.nkeys; i++)
+ gpf->kcnts[i] += pf->kcnts[i];
+ }
+
if (nla_put(skb, TCA_U32_PCNT,
sizeof(struct tc_u32_pcnt) + n->sel.nkeys*sizeof(u64),
- n->pf))
+ gpf)) {
+ kfree(gpf);
goto nla_put_failure;
+ }
+ kfree(gpf);
#endif
}
projects / firefly-linux-kernel-4.4.55.git / blobdiff