openwrtv3/target/linux/generic/patches-3.18/080-10-fib_trie-Use-unsigned-long-for-anything-dealing-with.patch
Felix Fietkau 944612680d kernel: backport fib_trie improvements/fixes from 4.0-rc
Signed-off-by: Felix Fietkau <nbd@openwrt.org>

SVN-Revision: 44695
2015-03-12 15:27:44 +00:00

186 lines
5.8 KiB
Diff

From: Alexander Duyck <alexander.h.duyck@redhat.com>
Date: Wed, 31 Dec 2014 10:56:18 -0800
Subject: [PATCH] fib_trie: Use unsigned long for anything dealing with a
shift by bits
This change makes it so that anything that can be shifted by, or compared
to a value shifted by bits is updated to be an unsigned long. This is
mostly a precaution against an insanely huge address space that somehow
starts coming close to the 2^32 root node size which would require
something like 1.5 billion addresses.
I chose unsigned long instead of unsigned long long since I do not believe
it is possible to allocate a 32 bit tnode on a 32 bit system as the memory
consumed would be 16GB + 28B which exceeds the addressible space for any
one process.
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -146,8 +146,8 @@ struct trie {
#endif
};
-static void tnode_put_child_reorg(struct tnode *tn, int i, struct tnode *n,
- int wasfull);
+static void tnode_put_child_reorg(struct tnode *tn, unsigned long i,
+ struct tnode *n, int wasfull);
static struct tnode *resize(struct trie *t, struct tnode *tn);
static struct tnode *inflate(struct trie *t, struct tnode *tn);
static struct tnode *halve(struct trie *t, struct tnode *tn);
@@ -183,25 +183,23 @@ static inline void node_set_parent(struc
/* This provides us with the number of children in this node, in the case of a
* leaf this will return 0 meaning none of the children are accessible.
*/
-static inline int tnode_child_length(const struct tnode *tn)
+static inline unsigned long tnode_child_length(const struct tnode *tn)
{
return (1ul << tn->bits) & ~(1ul);
}
-/*
- * caller must hold RTNL
- */
-static inline struct tnode *tnode_get_child(const struct tnode *tn, unsigned int i)
+/* caller must hold RTNL */
+static inline struct tnode *tnode_get_child(const struct tnode *tn,
+ unsigned long i)
{
BUG_ON(i >= tnode_child_length(tn));
return rtnl_dereference(tn->child[i]);
}
-/*
- * caller must hold RCU read lock or RTNL
- */
-static inline struct tnode *tnode_get_child_rcu(const struct tnode *tn, unsigned int i)
+/* caller must hold RCU read lock or RTNL */
+static inline struct tnode *tnode_get_child_rcu(const struct tnode *tn,
+ unsigned long i)
{
BUG_ON(i >= tnode_child_length(tn));
@@ -400,7 +398,7 @@ static inline int tnode_full(const struc
return n && ((n->pos + n->bits) == tn->pos) && IS_TNODE(n);
}
-static inline void put_child(struct tnode *tn, int i,
+static inline void put_child(struct tnode *tn, unsigned long i,
struct tnode *n)
{
tnode_put_child_reorg(tn, i, n, -1);
@@ -411,13 +409,13 @@ static inline void put_child(struct tnod
* Update the value of full_children and empty_children.
*/
-static void tnode_put_child_reorg(struct tnode *tn, int i, struct tnode *n,
- int wasfull)
+static void tnode_put_child_reorg(struct tnode *tn, unsigned long i,
+ struct tnode *n, int wasfull)
{
struct tnode *chi = rtnl_dereference(tn->child[i]);
int isfull;
- BUG_ON(i >= 1<<tn->bits);
+ BUG_ON(i >= tnode_child_length(tn));
/* update emptyChildren */
if (n == NULL && chi != NULL)
@@ -607,10 +605,10 @@ no_children:
static void tnode_clean_free(struct tnode *tn)
{
struct tnode *tofree;
- int i;
+ unsigned long i;
for (i = 0; i < tnode_child_length(tn); i++) {
- tofree = rtnl_dereference(tn->child[i]);
+ tofree = tnode_get_child(tn, i);
if (tofree)
node_free(tofree);
}
@@ -619,10 +617,10 @@ static void tnode_clean_free(struct tnod
static struct tnode *inflate(struct trie *t, struct tnode *oldtnode)
{
- int olen = tnode_child_length(oldtnode);
+ unsigned long olen = tnode_child_length(oldtnode);
struct tnode *tn;
+ unsigned long i;
t_key m;
- int i;
pr_debug("In inflate\n");
@@ -664,7 +662,7 @@ static struct tnode *inflate(struct trie
for (i = 0; i < olen; i++) {
struct tnode *inode = tnode_get_child(oldtnode, i);
struct tnode *left, *right;
- int size, j;
+ unsigned long size, j;
/* An empty child */
if (inode == NULL)
@@ -737,7 +735,7 @@ nomem:
static struct tnode *halve(struct trie *t, struct tnode *oldtnode)
{
- int olen = tnode_child_length(oldtnode);
+ unsigned long olen = tnode_child_length(oldtnode);
struct tnode *tn, *left, *right;
int i;
@@ -1532,9 +1530,9 @@ static int trie_flush_leaf(struct tnode
static struct tnode *leaf_walk_rcu(struct tnode *p, struct tnode *c)
{
do {
- t_key idx = c ? idx = get_index(c->key, p) + 1 : 0;
+ unsigned long idx = c ? idx = get_index(c->key, p) + 1 : 0;
- while (idx < 1u << p->bits) {
+ while (idx < tnode_child_length(p)) {
c = tnode_get_child_rcu(p, idx++);
if (!c)
continue;
@@ -1786,8 +1784,8 @@ struct fib_trie_iter {
static struct tnode *fib_trie_get_next(struct fib_trie_iter *iter)
{
+ unsigned long cindex = iter->index;
struct tnode *tn = iter->tnode;
- unsigned int cindex = iter->index;
struct tnode *p;
/* A single entry routing table */
@@ -1797,7 +1795,7 @@ static struct tnode *fib_trie_get_next(s
pr_debug("get_next iter={node=%p index=%d depth=%d}\n",
iter->tnode, iter->index, iter->depth);
rescan:
- while (cindex < (1<<tn->bits)) {
+ while (cindex < tnode_child_length(tn)) {
struct tnode *n = tnode_get_child_rcu(tn, cindex);
if (n) {
@@ -1874,15 +1872,16 @@ static void trie_collect_stats(struct tr
hlist_for_each_entry_rcu(li, &n->list, hlist)
++s->prefixes;
} else {
- int i;
+ unsigned long i;
s->tnodes++;
if (n->bits < MAX_STAT_DEPTH)
s->nodesizes[n->bits]++;
- for (i = 0; i < tnode_child_length(n); i++)
+ for (i = 0; i < tnode_child_length(n); i++) {
if (!rcu_access_pointer(n->child[i]))
s->nullpointers++;
+ }
}
}
rcu_read_unlock();