From aa1c366e4febc7f5c2b84958a2dd7cd70e28f9d0 Mon Sep 17 00:00:00 2001 From: dpward Date: Mon, 5 Sep 2011 16:47:24 +0000 Subject: [PATCH] net: Handle different key sizes between address families in flow cache With the conversion of struct flowi to a union of AF-specific structs, some operations on the flow cache need to account for the exact size of the key. Signed-off-by: David Ward Signed-off-by: David S. Miller --- include/net/flow.h | 19 +++++++++++++++++++ net/core/flow.c | 31 +++++++++++++++++-------------- 2 files changed, 36 insertions(+), 14 deletions(-) diff --git a/include/net/flow.h b/include/net/flow.h index 2ec377d9ab9f..a09447749e2d 100644 --- a/include/net/flow.h +++ b/include/net/flow.h @@ -7,6 +7,7 @@ #ifndef _NET_FLOW_H #define _NET_FLOW_H +#include #include #include @@ -161,6 +162,24 @@ static inline struct flowi *flowidn_to_flowi(struct flowidn *fldn) return container_of(fldn, struct flowi, u.dn); } +typedef unsigned long flow_compare_t; + +static inline size_t flow_key_size(u16 family) +{ + switch (family) { + case AF_INET: + BUILD_BUG_ON(sizeof(struct flowi4) % sizeof(flow_compare_t)); + return sizeof(struct flowi4) / sizeof(flow_compare_t); + case AF_INET6: + BUILD_BUG_ON(sizeof(struct flowi6) % sizeof(flow_compare_t)); + return sizeof(struct flowi6) / sizeof(flow_compare_t); + case AF_DECnet: + BUILD_BUG_ON(sizeof(struct flowidn) % sizeof(flow_compare_t)); + return sizeof(struct flowidn) / sizeof(flow_compare_t); + } + return 0; +} + #define FLOW_DIR_IN 0 #define FLOW_DIR_OUT 1 #define FLOW_DIR_FWD 2 diff --git a/net/core/flow.c b/net/core/flow.c index 47b6d26c2afb..555a456efb07 100644 --- a/net/core/flow.c +++ b/net/core/flow.c @@ -173,29 +173,26 @@ static void flow_new_hash_rnd(struct flow_cache *fc, static u32 flow_hash_code(struct flow_cache *fc, struct flow_cache_percpu *fcp, - const struct flowi *key) + const struct flowi *key, + size_t keysize) { const u32 *k = (const u32 *) key; + const u32 length = keysize * sizeof(flow_compare_t) / sizeof(u32); - return jhash2(k, (sizeof(*key) / sizeof(u32)), fcp->hash_rnd) + return jhash2(k, length, fcp->hash_rnd) & (flow_cache_hash_size(fc) - 1); } -typedef unsigned long flow_compare_t; - /* I hear what you're saying, use memcmp. But memcmp cannot make - * important assumptions that we can here, such as alignment and - * constant size. + * important assumptions that we can here, such as alignment. */ -static int flow_key_compare(const struct flowi *key1, const struct flowi *key2) +static int flow_key_compare(const struct flowi *key1, const struct flowi *key2, + size_t keysize) { const flow_compare_t *k1, *k1_lim, *k2; - const int n_elem = sizeof(struct flowi) / sizeof(flow_compare_t); - - BUILD_BUG_ON(sizeof(struct flowi) % sizeof(flow_compare_t)); k1 = (const flow_compare_t *) key1; - k1_lim = k1 + n_elem; + k1_lim = k1 + keysize; k2 = (const flow_compare_t *) key2; @@ -216,6 +213,7 @@ flow_cache_lookup(struct net *net, const struct flowi *key, u16 family, u8 dir, struct flow_cache_entry *fle, *tfle; struct hlist_node *entry; struct flow_cache_object *flo; + size_t keysize; unsigned int hash; local_bh_disable(); @@ -223,6 +221,11 @@ flow_cache_lookup(struct net *net, const struct flowi *key, u16 family, u8 dir, fle = NULL; flo = NULL; + + keysize = flow_key_size(family); + if (!keysize) + goto nocache; + /* Packet really early in init? Making flow_cache_init a * pre-smp initcall would solve this. --RR */ if (!fcp->hash_table) @@ -231,12 +234,12 @@ flow_cache_lookup(struct net *net, const struct flowi *key, u16 family, u8 dir, if (fcp->hash_rnd_recalc) flow_new_hash_rnd(fc, fcp); - hash = flow_hash_code(fc, fcp, key); + hash = flow_hash_code(fc, fcp, key, keysize); hlist_for_each_entry(tfle, entry, &fcp->hash_table[hash], u.hlist) { if (tfle->net == net && tfle->family == family && tfle->dir == dir && - flow_key_compare(key, &tfle->key) == 0) { + flow_key_compare(key, &tfle->key, keysize) == 0) { fle = tfle; break; } @@ -251,7 +254,7 @@ flow_cache_lookup(struct net *net, const struct flowi *key, u16 family, u8 dir, fle->net = net; fle->family = family; fle->dir = dir; - memcpy(&fle->key, key, sizeof(*key)); + memcpy(&fle->key, key, keysize * sizeof(flow_compare_t)); fle->object = NULL; hlist_add_head(&fle->u.hlist, &fcp->hash_table[hash]); fcp->hash_count++; -- 2.20.1