kernel_optimize_test/net/sched/cls_u32.c
John Fastabend 9e8ce79cd7 net: sched: cls_u32 add bit to specify software only rules
In the initial implementation the only way to stop a rule from being
inserted into the hardware table was via the device feature flag.
However this doesn't work well when working on an end host system
where packets are expect to hit both the hardware and software
datapaths.

For example we can imagine a rule that will match an IP address and
increment a field. If we install this rule in both hardware and
software we may increment the field twice. To date we have only
added support for the drop action so we have been able to ignore
these cases. But as we extend the action support we will hit this
example plus more such cases. Arguably these are not even corner
cases in many working systems these cases will be common.

To avoid forcing the driver to always abort (i.e. the above example)
this patch adds a flag to add a rule in software only. A careful
user can use this flag to build software and hardware datapaths
that work together. One example we have found particularly useful
is to use hardware resources to set the skb->mark on the skb when
the match may be expensive to run in software but a mark lookup
in a hash table is cheap. The idea here is hardware can do in one
lookup what the u32 classifier may need to traverse multiple lists
and hash tables to compute. The flag is only passed down on inserts.
On deletion to avoid stale references in hardware we always try
to remove a rule if it exists.

The flags field is part of the classifier specific options. Although
it is tempting to lift this into the generic structure doing this
proves difficult do to how the tc netlink attributes are implemented
along with how the dump/change routines are called. There is also
precedence for putting seemingly generic pieces in the specific
classifier options such as TCA_U32_POLICE, TCA_U32_ACT, etc. So
although not ideal I've left FLAGS in the u32 options as well as it
simplifies the code greatly and user space has already learned how
to manage these bits ala 'tc' tool.

Another thing if trying to update a rule we require the flags to
be unchanged. This is to force user space, software u32 and
the hardware u32 to keep in sync. Thanks to Simon Horman for
catching this case.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-01 16:05:39 -05:00

1201 lines
27 KiB
C

/*
* net/sched/cls_u32.c Ugly (or Universal) 32bit key Packet Classifier.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*
* The filters are packed to hash tables of key nodes
* with a set of 32bit key/mask pairs at every node.
* Nodes reference next level hash tables etc.
*
* This scheme is the best universal classifier I managed to
* invent; it is not super-fast, but it is not slow (provided you
* program it correctly), and general enough. And its relative
* speed grows as the number of rules becomes larger.
*
* It seems that it represents the best middle point between
* speed and manageability both by human and by machine.
*
* It is especially useful for link sharing combined with QoS;
* pure RSVP doesn't need such a general approach and can use
* much simpler (and faster) schemes, sort of cls_rsvp.c.
*
* JHS: We should remove the CONFIG_NET_CLS_IND from here
* eventually when the meta match extension is made available
*
* nfmark match added by Catalin(ux aka Dino) BOIE <catab at umbrella.ro>
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/types.h>
#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/netlink.h>
#include <net/act_api.h>
#include <net/pkt_cls.h>
#include <linux/netdevice.h>
struct tc_u_knode {
struct tc_u_knode __rcu *next;
u32 handle;
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 __rcu *ht_down;
#ifdef CONFIG_CLS_U32_PERF
struct tc_u32_pcnt __percpu *pf;
#endif
u32 flags;
#ifdef CONFIG_CLS_U32_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 __rcu *next;
u32 handle;
u32 prio;
struct tc_u_common *tp_c;
int refcnt;
unsigned int divisor;
struct rcu_head rcu;
/* The 'ht' field MUST be the last field in structure to allow for
* more entries allocated at end of structure.
*/
struct tc_u_knode __rcu *ht[1];
};
struct tc_u_common {
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,
const struct tc_u32_sel *sel,
u8 fshift)
{
unsigned int h = ntohl(key & sel->hmask) >> fshift;
return h;
}
static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp, struct tcf_result *res)
{
struct {
struct tc_u_knode *knode;
unsigned int off;
} stack[TC_U32_MAXDEPTH];
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 off2 = 0;
int sel = 0;
#ifdef CONFIG_CLS_U32_PERF
int j;
#endif
int i, r;
next_ht:
n = rcu_dereference_bh(ht->ht[sel]);
next_knode:
if (n) {
struct tc_u32_key *key = n->sel.keys;
#ifdef CONFIG_CLS_U32_PERF
__this_cpu_inc(n->pf->rcnt);
j = 0;
#endif
#ifdef CONFIG_CLS_U32_MARK
if ((skb->mark & n->mask) != n->val) {
n = rcu_dereference_bh(n->next);
goto next_knode;
} else {
__this_cpu_inc(*n->pcpu_success);
}
#endif
for (i = n->sel.nkeys; i > 0; i--, key++) {
int toff = off + key->off + (off2 & key->offmask);
__be32 *data, hdata;
if (skb_headroom(skb) + toff > INT_MAX)
goto out;
data = skb_header_pointer(skb, toff, 4, &hdata);
if (!data)
goto out;
if ((*data ^ key->val) & key->mask) {
n = rcu_dereference_bh(n->next);
goto next_knode;
}
#ifdef CONFIG_CLS_U32_PERF
__this_cpu_inc(n->pf->kcnts[j]);
j++;
#endif
}
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 = rcu_dereference_bh(n->next);
goto next_knode;
}
#endif
#ifdef CONFIG_CLS_U32_PERF
__this_cpu_inc(n->pf->rhit);
#endif
r = tcf_exts_exec(skb, &n->exts, res);
if (r < 0) {
n = rcu_dereference_bh(n->next);
goto next_knode;
}
return r;
}
n = rcu_dereference_bh(n->next);
goto next_knode;
}
/* PUSH */
if (sdepth >= TC_U32_MAXDEPTH)
goto deadloop;
stack[sdepth].knode = n;
stack[sdepth].off = off;
sdepth++;
ht = rcu_dereference_bh(n->ht_down);
sel = 0;
if (ht->divisor) {
__be32 *data, hdata;
data = skb_header_pointer(skb, off + n->sel.hoff, 4,
&hdata);
if (!data)
goto out;
sel = ht->divisor & u32_hash_fold(*data, &n->sel,
n->fshift);
}
if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
goto next_ht;
if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
off2 = n->sel.off + 3;
if (n->sel.flags & TC_U32_VAROFFSET) {
__be16 *data, hdata;
data = skb_header_pointer(skb,
off + n->sel.offoff,
2, &hdata);
if (!data)
goto out;
off2 += ntohs(n->sel.offmask & *data) >>
n->sel.offshift;
}
off2 &= ~3;
}
if (n->sel.flags & TC_U32_EAT) {
off += off2;
off2 = 0;
}
if (off < skb->len)
goto next_ht;
}
/* POP */
if (sdepth--) {
n = stack[sdepth].knode;
ht = rcu_dereference_bh(n->ht_up);
off = stack[sdepth].off;
goto check_terminal;
}
out:
return -1;
deadloop:
net_warn_ratelimited("cls_u32: dead loop\n");
return -1;
}
static struct tc_u_hnode *
u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
{
struct tc_u_hnode *ht;
for (ht = rtnl_dereference(tp_c->hlist);
ht;
ht = rtnl_dereference(ht->next))
if (ht->handle == handle)
break;
return ht;
}
static struct tc_u_knode *
u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
{
unsigned int sel;
struct tc_u_knode *n = NULL;
sel = TC_U32_HASH(handle);
if (sel > ht->divisor)
goto out;
for (n = rtnl_dereference(ht->ht[sel]);
n;
n = rtnl_dereference(n->next))
if (n->handle == handle)
break;
out:
return n;
}
static unsigned long u32_get(struct tcf_proto *tp, u32 handle)
{
struct tc_u_hnode *ht;
struct tc_u_common *tp_c = tp->data;
if (TC_U32_HTID(handle) == TC_U32_ROOT)
ht = rtnl_dereference(tp->root);
else
ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
if (!ht)
return 0;
if (TC_U32_KEY(handle) == 0)
return (unsigned long)ht;
return (unsigned long)u32_lookup_key(ht, handle);
}
static u32 gen_new_htid(struct tc_u_common *tp_c)
{
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;
} while (--i > 0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20));
return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0;
}
static int u32_init(struct tcf_proto *tp)
{
struct tc_u_hnode *root_ht;
struct tc_u_common *tp_c;
tp_c = tp->q->u32_node;
root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL);
if (root_ht == NULL)
return -ENOBUFS;
root_ht->divisor = 0;
root_ht->refcnt++;
root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
root_ht->prio = tp->prio;
if (tp_c == NULL) {
tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
if (tp_c == NULL) {
kfree(root_ht);
return -ENOBUFS;
}
tp_c->q = tp->q;
tp->q->u32_node = tp_c;
}
tp_c->refcnt++;
RCU_INIT_POINTER(root_ht->next, tp_c->hlist);
rcu_assign_pointer(tp_c->hlist, root_ht);
root_ht->tp_c = tp_c;
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,
bool free_pf)
{
tcf_exts_destroy(&n->exts);
if (n->ht_down)
n->ht_down->refcnt--;
#ifdef CONFIG_CLS_U32_PERF
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 __rcu **kp;
struct tc_u_knode *pkp;
struct tc_u_hnode *ht = rtnl_dereference(key->ht_up);
if (ht) {
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;
}
}
}
WARN_ON(1);
return 0;
}
static void u32_remove_hw_knode(struct tcf_proto *tp, u32 handle)
{
struct net_device *dev = tp->q->dev_queue->dev;
struct tc_cls_u32_offload u32_offload = {0};
struct tc_to_netdev offload;
offload.type = TC_SETUP_CLSU32;
offload.cls_u32 = &u32_offload;
if (tc_should_offload(dev, 0)) {
offload.cls_u32->command = TC_CLSU32_DELETE_KNODE;
offload.cls_u32->knode.handle = handle;
dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
tp->protocol, &offload);
}
}
static void u32_replace_hw_hnode(struct tcf_proto *tp,
struct tc_u_hnode *h,
u32 flags)
{
struct net_device *dev = tp->q->dev_queue->dev;
struct tc_cls_u32_offload u32_offload = {0};
struct tc_to_netdev offload;
offload.type = TC_SETUP_CLSU32;
offload.cls_u32 = &u32_offload;
if (tc_should_offload(dev, flags)) {
offload.cls_u32->command = TC_CLSU32_NEW_HNODE;
offload.cls_u32->hnode.divisor = h->divisor;
offload.cls_u32->hnode.handle = h->handle;
offload.cls_u32->hnode.prio = h->prio;
dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
tp->protocol, &offload);
}
}
static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h)
{
struct net_device *dev = tp->q->dev_queue->dev;
struct tc_cls_u32_offload u32_offload = {0};
struct tc_to_netdev offload;
offload.type = TC_SETUP_CLSU32;
offload.cls_u32 = &u32_offload;
if (tc_should_offload(dev, 0)) {
offload.cls_u32->command = TC_CLSU32_DELETE_HNODE;
offload.cls_u32->hnode.divisor = h->divisor;
offload.cls_u32->hnode.handle = h->handle;
offload.cls_u32->hnode.prio = h->prio;
dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
tp->protocol, &offload);
}
}
static void u32_replace_hw_knode(struct tcf_proto *tp,
struct tc_u_knode *n,
u32 flags)
{
struct net_device *dev = tp->q->dev_queue->dev;
struct tc_cls_u32_offload u32_offload = {0};
struct tc_to_netdev offload;
offload.type = TC_SETUP_CLSU32;
offload.cls_u32 = &u32_offload;
if (tc_should_offload(dev, flags)) {
offload.cls_u32->command = TC_CLSU32_REPLACE_KNODE;
offload.cls_u32->knode.handle = n->handle;
offload.cls_u32->knode.fshift = n->fshift;
#ifdef CONFIG_CLS_U32_MARK
offload.cls_u32->knode.val = n->val;
offload.cls_u32->knode.mask = n->mask;
#else
offload.cls_u32->knode.val = 0;
offload.cls_u32->knode.mask = 0;
#endif
offload.cls_u32->knode.sel = &n->sel;
offload.cls_u32->knode.exts = &n->exts;
if (n->ht_down)
offload.cls_u32->knode.link_handle = n->ht_down->handle;
dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
tp->protocol, &offload);
}
}
static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
{
struct tc_u_knode *n;
unsigned int h;
for (h = 0; h <= ht->divisor; h++) {
while ((n = rtnl_dereference(ht->ht[h])) != NULL) {
RCU_INIT_POINTER(ht->ht[h],
rtnl_dereference(n->next));
tcf_unbind_filter(tp, &n->res);
u32_remove_hw_knode(tp, n->handle);
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 __rcu **hn;
struct tc_u_hnode *phn;
WARN_ON(ht->refcnt);
u32_clear_hnode(tp, ht);
hn = &tp_c->hlist;
for (phn = rtnl_dereference(*hn);
phn;
hn = &phn->next, phn = rtnl_dereference(*hn)) {
if (phn == ht) {
u32_clear_hw_hnode(tp, ht);
RCU_INIT_POINTER(*hn, ht->next);
kfree_rcu(ht, rcu);
return 0;
}
}
return -ENOENT;
}
static bool ht_empty(struct tc_u_hnode *ht)
{
unsigned int h;
for (h = 0; h <= ht->divisor; h++)
if (rcu_access_pointer(ht->ht[h]))
return false;
return true;
}
static bool u32_destroy(struct tcf_proto *tp, bool force)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
WARN_ON(root_ht == NULL);
if (!force) {
if (root_ht) {
if (root_ht->refcnt > 1)
return false;
if (root_ht->refcnt == 1) {
if (!ht_empty(root_ht))
return false;
}
}
if (tp_c->refcnt > 1)
return false;
if (tp_c->refcnt == 1) {
struct tc_u_hnode *ht;
for (ht = rtnl_dereference(tp_c->hlist);
ht;
ht = rtnl_dereference(ht->next))
if (!ht_empty(ht))
return false;
}
}
if (root_ht && --root_ht->refcnt == 0)
u32_destroy_hnode(tp, root_ht);
if (--tp_c->refcnt == 0) {
struct tc_u_hnode *ht;
tp->q->u32_node = NULL;
for (ht = rtnl_dereference(tp_c->hlist);
ht;
ht = rtnl_dereference(ht->next)) {
ht->refcnt--;
u32_clear_hnode(tp, ht);
}
while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) {
RCU_INIT_POINTER(tp_c->hlist, ht->next);
kfree_rcu(ht, rcu);
}
kfree(tp_c);
}
tp->data = NULL;
return true;
}
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)) {
u32_remove_hw_knode(tp, ht->handle);
return u32_delete_key(tp, (struct tc_u_knode *)ht);
}
if (root_ht == ht)
return -EINVAL;
if (ht->refcnt == 1) {
ht->refcnt--;
u32_destroy_hnode(tp, ht);
} else {
return -EBUSY;
}
return 0;
}
#define NR_U32_NODE (1<<12)
static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle)
{
struct tc_u_knode *n;
unsigned long i;
unsigned long *bitmap = kzalloc(BITS_TO_LONGS(NR_U32_NODE) * sizeof(unsigned long),
GFP_KERNEL);
if (!bitmap)
return handle | 0xFFF;
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);
if (i >= NR_U32_NODE)
i = find_next_zero_bit(bitmap, NR_U32_NODE, 1);
kfree(bitmap);
return handle | (i >= NR_U32_NODE ? 0xFFF : i);
}
static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
[TCA_U32_CLASSID] = { .type = NLA_U32 },
[TCA_U32_HASH] = { .type = NLA_U32 },
[TCA_U32_LINK] = { .type = NLA_U32 },
[TCA_U32_DIVISOR] = { .type = NLA_U32 },
[TCA_U32_SEL] = { .len = sizeof(struct tc_u32_sel) },
[TCA_U32_INDEV] = { .type = NLA_STRING, .len = IFNAMSIZ },
[TCA_U32_MARK] = { .len = sizeof(struct tc_u32_mark) },
[TCA_U32_FLAGS] = { .type = NLA_U32 },
};
static int u32_set_parms(struct net *net, struct tcf_proto *tp,
unsigned long base, struct tc_u_hnode *ht,
struct tc_u_knode *n, struct nlattr **tb,
struct nlattr *est, bool ovr)
{
int err;
struct tcf_exts e;
tcf_exts_init(&e, TCA_U32_ACT, TCA_U32_POLICE);
err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
if (err < 0)
return err;
err = -EINVAL;
if (tb[TCA_U32_LINK]) {
u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
struct tc_u_hnode *ht_down = NULL, *ht_old;
if (TC_U32_KEY(handle))
goto errout;
if (handle) {
ht_down = u32_lookup_ht(ht->tp_c, handle);
if (ht_down == NULL)
goto errout;
ht_down->refcnt++;
}
ht_old = rtnl_dereference(n->ht_down);
rcu_assign_pointer(n->ht_down, ht_down);
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);
}
#ifdef CONFIG_NET_CLS_IND
if (tb[TCA_U32_INDEV]) {
int ret;
ret = tcf_change_indev(net, tb[TCA_U32_INDEV]);
if (ret < 0)
goto errout;
n->ifindex = ret;
}
#endif
tcf_exts_change(tp, &n->exts, &e);
return 0;
errout:
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;
new->flags = n->flags;
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,
unsigned long *arg, bool ovr)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_hnode *ht;
struct tc_u_knode *n;
struct tc_u32_sel *s;
struct nlattr *opt = tca[TCA_OPTIONS];
struct nlattr *tb[TCA_U32_MAX + 1];
u32 htid, flags = 0;
int err;
#ifdef CONFIG_CLS_U32_PERF
size_t size;
#endif
if (opt == NULL)
return handle ? -EINVAL : 0;
err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy);
if (err < 0)
return err;
if (tb[TCA_U32_FLAGS])
flags = nla_get_u32(tb[TCA_U32_FLAGS]);
n = (struct tc_u_knode *)*arg;
if (n) {
struct tc_u_knode *new;
if (TC_U32_KEY(n->handle) == 0)
return -EINVAL;
if (n->flags != flags)
return -EINVAL;
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);
u32_replace_hw_knode(tp, new, flags);
return 0;
}
if (tb[TCA_U32_DIVISOR]) {
unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
if (--divisor > 0x100)
return -EINVAL;
if (TC_U32_KEY(handle))
return -EINVAL;
if (handle == 0) {
handle = gen_new_htid(tp->data);
if (handle == 0)
return -ENOMEM;
}
ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL);
if (ht == NULL)
return -ENOBUFS;
ht->tp_c = tp_c;
ht->refcnt = 1;
ht->divisor = divisor;
ht->handle = handle;
ht->prio = tp->prio;
RCU_INIT_POINTER(ht->next, tp_c->hlist);
rcu_assign_pointer(tp_c->hlist, ht);
*arg = (unsigned long)ht;
u32_replace_hw_hnode(tp, ht, flags);
return 0;
}
if (tb[TCA_U32_HASH]) {
htid = nla_get_u32(tb[TCA_U32_HASH]);
if (TC_U32_HTID(htid) == TC_U32_ROOT) {
ht = rtnl_dereference(tp->root);
htid = ht->handle;
} else {
ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
if (ht == NULL)
return -EINVAL;
}
} else {
ht = rtnl_dereference(tp->root);
htid = ht->handle;
}
if (ht->divisor < TC_U32_HASH(htid))
return -EINVAL;
if (handle) {
if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid))
return -EINVAL;
handle = htid | TC_U32_NODE(handle);
} else
handle = gen_new_kid(ht, htid);
if (tb[TCA_U32_SEL] == NULL)
return -EINVAL;
s = nla_data(tb[TCA_U32_SEL]);
n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL);
if (n == NULL)
return -ENOBUFS;
#ifdef CONFIG_CLS_U32_PERF
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));
RCU_INIT_POINTER(n->ht_up, ht);
n->handle = handle;
n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
n->flags = flags;
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]);
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 __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;
RCU_INIT_POINTER(n->next, pins);
rcu_assign_pointer(*ins, n);
u32_replace_hw_knode(tp, n, flags);
*arg = (unsigned long)n;
return 0;
}
#ifdef CONFIG_CLS_U32_MARK
free_percpu(n->pcpu_success);
errout:
#endif
#ifdef CONFIG_CLS_U32_PERF
free_percpu(n->pf);
#endif
kfree(n);
return err;
}
static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_hnode *ht;
struct tc_u_knode *n;
unsigned int h;
if (arg->stop)
return;
for (ht = rtnl_dereference(tp_c->hlist);
ht;
ht = rtnl_dereference(ht->next)) {
if (ht->prio != tp->prio)
continue;
if (arg->count >= arg->skip) {
if (arg->fn(tp, (unsigned long)ht, arg) < 0) {
arg->stop = 1;
return;
}
}
arg->count++;
for (h = 0; h <= ht->divisor; h++) {
for (n = rtnl_dereference(ht->ht[h]);
n;
n = rtnl_dereference(n->next)) {
if (arg->count < arg->skip) {
arg->count++;
continue;
}
if (arg->fn(tp, (unsigned long)n, arg) < 0) {
arg->stop = 1;
return;
}
arg->count++;
}
}
}
}
static int u32_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
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)
return skb->len;
t->tcm_handle = n->handle;
nest = nla_nest_start(skb, TCA_OPTIONS);
if (nest == NULL)
goto nla_put_failure;
if (TC_U32_KEY(n->handle) == 0) {
struct tc_u_hnode *ht = (struct tc_u_hnode *)fh;
u32 divisor = ht->divisor + 1;
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;
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;
ht_down = rtnl_dereference(n->ht_down);
if (ht_down &&
nla_put_u32(skb, TCA_U32_LINK, ht_down->handle))
goto nla_put_failure;
if (n->flags && nla_put_u32(skb, TCA_U32_FLAGS, n->flags))
goto nla_put_failure;
#ifdef CONFIG_CLS_U32_MARK
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)
goto nla_put_failure;
#ifdef CONFIG_NET_CLS_IND
if (n->ifindex) {
struct net_device *dev;
dev = __dev_get_by_index(net, n->ifindex);
if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name))
goto nla_put_failure;
}
#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),
gpf)) {
kfree(gpf);
goto nla_put_failure;
}
kfree(gpf);
#endif
}
nla_nest_end(skb, nest);
if (TC_U32_KEY(n->handle))
if (tcf_exts_dump_stats(skb, &n->exts) < 0)
goto nla_put_failure;
return skb->len;
nla_put_failure:
nla_nest_cancel(skb, nest);
return -1;
}
static struct tcf_proto_ops cls_u32_ops __read_mostly = {
.kind = "u32",
.classify = u32_classify,
.init = u32_init,
.destroy = u32_destroy,
.get = u32_get,
.change = u32_change,
.delete = u32_delete,
.walk = u32_walk,
.dump = u32_dump,
.owner = THIS_MODULE,
};
static int __init init_u32(void)
{
pr_info("u32 classifier\n");
#ifdef CONFIG_CLS_U32_PERF
pr_info(" Performance counters on\n");
#endif
#ifdef CONFIG_NET_CLS_IND
pr_info(" input device check on\n");
#endif
#ifdef CONFIG_NET_CLS_ACT
pr_info(" Actions configured\n");
#endif
return register_tcf_proto_ops(&cls_u32_ops);
}
static void __exit exit_u32(void)
{
unregister_tcf_proto_ops(&cls_u32_ops);
}
module_init(init_u32)
module_exit(exit_u32)
MODULE_LICENSE("GPL");