summaryrefslogtreecommitdiff
path: root/net/sched/cls_u32.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/sched/cls_u32.c')
-rw-r--r--net/sched/cls_u32.c105
1 files changed, 87 insertions, 18 deletions
diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c
index d15d50de7980..da4c179a4d41 100644
--- a/net/sched/cls_u32.c
+++ b/net/sched/cls_u32.c
@@ -712,8 +712,23 @@ static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
[TCA_U32_FLAGS] = { .type = NLA_U32 },
};
+static void u32_unbind_filter(struct tcf_proto *tp, struct tc_u_knode *n,
+ struct nlattr **tb)
+{
+ if (tb[TCA_U32_CLASSID])
+ tcf_unbind_filter(tp, &n->res);
+}
+
+static void u32_bind_filter(struct tcf_proto *tp, struct tc_u_knode *n,
+ unsigned long base, struct nlattr **tb)
+{
+ if (tb[TCA_U32_CLASSID]) {
+ n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
+ tcf_bind_filter(tp, &n->res, base);
+ }
+}
+
static int u32_set_parms(struct net *net, struct tcf_proto *tp,
- unsigned long base,
struct tc_u_knode *n, struct nlattr **tb,
struct nlattr *est, u32 flags, u32 fl_flags,
struct netlink_ext_ack *extack)
@@ -760,10 +775,6 @@ static int u32_set_parms(struct net *net, struct tcf_proto *tp,
if (ht_old)
ht_old->refcnt--;
}
- if (tb[TCA_U32_CLASSID]) {
- n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
- tcf_bind_filter(tp, &n->res, base);
- }
if (ifindex >= 0)
n->ifindex = ifindex;
@@ -815,7 +826,6 @@ static struct tc_u_knode *u32_init_knode(struct net *net, struct tcf_proto *tp,
new->ifindex = n->ifindex;
new->fshift = n->fshift;
- new->res = n->res;
new->flags = n->flags;
RCU_INIT_POINTER(new->ht_down, ht);
@@ -903,17 +913,27 @@ static int u32_change(struct net *net, struct sk_buff *in_skb,
if (!new)
return -ENOMEM;
- err = u32_set_parms(net, tp, base, new, tb,
- tca[TCA_RATE], flags, new->flags,
- extack);
+ err = u32_set_parms(net, tp, new, tb, tca[TCA_RATE],
+ flags, new->flags, extack);
if (err) {
__u32_destroy_key(new);
return err;
}
+ u32_bind_filter(tp, new, base, tb);
+
err = u32_replace_hw_knode(tp, new, flags, extack);
if (err) {
+ u32_unbind_filter(tp, new, tb);
+
+ if (tb[TCA_U32_LINK]) {
+ struct tc_u_hnode *ht_old;
+
+ ht_old = rtnl_dereference(n->ht_down);
+ if (ht_old)
+ ht_old->refcnt++;
+ }
__u32_destroy_key(new);
return err;
}
@@ -1003,18 +1023,62 @@ static int u32_change(struct net *net, struct sk_buff *in_skb,
return -EINVAL;
}
+ /* At this point, we need to derive the new handle that will be used to
+ * uniquely map the identity of this table match entry. The
+ * identity of the entry that we need to construct is 32 bits made of:
+ * htid(12b):bucketid(8b):node/entryid(12b)
+ *
+ * At this point _we have the table(ht)_ in which we will insert this
+ * entry. We carry the table's id in variable "htid".
+ * Note that earlier code picked the ht selection either by a) the user
+ * providing the htid specified via TCA_U32_HASH attribute or b) when
+ * no such attribute is passed then the root ht, is default to at ID
+ * 0x[800][00][000]. Rule: the root table has a single bucket with ID 0.
+ * If OTOH the user passed us the htid, they may also pass a bucketid of
+ * choice. 0 is fine. For example a user htid is 0x[600][01][000] it is
+ * indicating hash bucketid of 1. Rule: the entry/node ID _cannot_ be
+ * passed via the htid, so even if it was non-zero it will be ignored.
+ *
+ * We may also have a handle, if the user passed one. The handle also
+ * carries the same addressing of htid(12b):bucketid(8b):node/entryid(12b).
+ * Rule: the bucketid on the handle is ignored even if one was passed;
+ * rather the value on "htid" is always assumed to be the bucketid.
+ */
if (handle) {
+ /* Rule: The htid from handle and tableid from htid must match */
if (TC_U32_HTID(handle) && TC_U32_HTID(handle ^ htid)) {
NL_SET_ERR_MSG_MOD(extack, "Handle specified hash table address mismatch");
return -EINVAL;
}
- handle = htid | TC_U32_NODE(handle);
- err = idr_alloc_u32(&ht->handle_idr, NULL, &handle, handle,
- GFP_KERNEL);
- if (err)
- return err;
- } else
+ /* Ok, so far we have a valid htid(12b):bucketid(8b) but we
+ * need to finalize the table entry identification with the last
+ * part - the node/entryid(12b)). Rule: Nodeid _cannot be 0_ for
+ * entries. Rule: nodeid of 0 is reserved only for tables(see
+ * earlier code which processes TC_U32_DIVISOR attribute).
+ * Rule: The nodeid can only be derived from the handle (and not
+ * htid).
+ * Rule: if the handle specified zero for the node id example
+ * 0x60000000, then pick a new nodeid from the pool of IDs
+ * this hash table has been allocating from.
+ * If OTOH it is specified (i.e for example the user passed a
+ * handle such as 0x60000123), then we use it generate our final
+ * handle which is used to uniquely identify the match entry.
+ */
+ if (!TC_U32_NODE(handle)) {
+ handle = gen_new_kid(ht, htid);
+ } else {
+ handle = htid | TC_U32_NODE(handle);
+ err = idr_alloc_u32(&ht->handle_idr, NULL, &handle,
+ handle, GFP_KERNEL);
+ if (err)
+ return err;
+ }
+ } else {
+ /* The user did not give us a handle; lets just generate one
+ * from the table's pool of nodeids.
+ */
handle = gen_new_kid(ht, htid);
+ }
if (tb[TCA_U32_SEL] == NULL) {
NL_SET_ERR_MSG_MOD(extack, "Selector not specified");
@@ -1074,15 +1138,18 @@ static int u32_change(struct net *net, struct sk_buff *in_skb,
}
#endif
- err = u32_set_parms(net, tp, base, n, tb, tca[TCA_RATE],
+ err = u32_set_parms(net, tp, n, tb, tca[TCA_RATE],
flags, n->flags, extack);
+
+ u32_bind_filter(tp, n, base, tb);
+
if (err == 0) {
struct tc_u_knode __rcu **ins;
struct tc_u_knode *pins;
err = u32_replace_hw_knode(tp, n, flags, extack);
if (err)
- goto errhw;
+ goto errunbind;
if (!tc_in_hw(n->flags))
n->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
@@ -1100,7 +1167,9 @@ static int u32_change(struct net *net, struct sk_buff *in_skb,
return 0;
}
-errhw:
+errunbind:
+ u32_unbind_filter(tp, n, tb);
+
#ifdef CONFIG_CLS_U32_MARK
free_percpu(n->pcpu_success);
#endif