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[NETFILTER]: nf_conntrack: remove old memory allocator of conntrack
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Now memory space for help and NAT are allocated by extension
infrastructure.

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Yasuyuki Kozakai authored and David S. Miller committed Jul 11, 2007
1 parent ff09b74 commit dacd2a1
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Showing 6 changed files with 15 additions and 242 deletions.
14 changes: 0 additions & 14 deletions include/net/netfilter/nf_conntrack.h
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Original file line number Diff line number Diff line change
Expand Up @@ -117,9 +117,6 @@ struct nf_conn
/* Unique ID that identifies this conntrack*/
unsigned int id;

/* features - nat, helper, ... used by allocating system */
u_int32_t features;

#if defined(CONFIG_NF_CONNTRACK_MARK)
u_int32_t mark;
#endif
Expand All @@ -133,9 +130,6 @@ struct nf_conn

/* Extensions */
struct nf_ct_ext *ext;

/* features dynamically at the end: helper, nat (both optional) */
char data[0];
};

static inline struct nf_conn *
Expand Down Expand Up @@ -265,14 +259,6 @@ do { \
local_bh_enable(); \
} while (0)

/* no helper, no nat */
#define NF_CT_F_BASIC 0
/* for helper */
#define NF_CT_F_HELP 1
/* for nat. */
#define NF_CT_F_NAT 2
#define NF_CT_F_NUM 4

extern int
nf_conntrack_register_cache(u_int32_t features, const char *name, size_t size);
extern void
Expand Down
2 changes: 0 additions & 2 deletions include/net/netfilter/nf_conntrack_l3proto.h
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Original file line number Diff line number Diff line change
Expand Up @@ -64,8 +64,6 @@ struct nf_conntrack_l3proto
int (*prepare)(struct sk_buff **pskb, unsigned int hooknum,
unsigned int *dataoff, u_int8_t *protonum);

u_int32_t (*get_features)(const struct nf_conntrack_tuple *tuple);

int (*tuple_to_nfattr)(struct sk_buff *skb,
const struct nf_conntrack_tuple *t);

Expand Down
6 changes: 0 additions & 6 deletions net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
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Original file line number Diff line number Diff line change
Expand Up @@ -103,11 +103,6 @@ ipv4_prepare(struct sk_buff **pskb, unsigned int hooknum, unsigned int *dataoff,
return NF_ACCEPT;
}

static u_int32_t ipv4_get_features(const struct nf_conntrack_tuple *tuple)
{
return NF_CT_F_BASIC;
}

static unsigned int ipv4_confirm(unsigned int hooknum,
struct sk_buff **pskb,
const struct net_device *in,
Expand Down Expand Up @@ -419,7 +414,6 @@ struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv4 = {
.print_tuple = ipv4_print_tuple,
.print_conntrack = ipv4_print_conntrack,
.prepare = ipv4_prepare,
.get_features = ipv4_get_features,
#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
.tuple_to_nfattr = ipv4_tuple_to_nfattr,
.nfattr_to_tuple = ipv4_nfattr_to_tuple,
Expand Down
6 changes: 0 additions & 6 deletions net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
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Original file line number Diff line number Diff line change
Expand Up @@ -147,11 +147,6 @@ ipv6_prepare(struct sk_buff **pskb, unsigned int hooknum, unsigned int *dataoff,
return NF_ACCEPT;
}

static u_int32_t ipv6_get_features(const struct nf_conntrack_tuple *tuple)
{
return NF_CT_F_BASIC;
}

static unsigned int ipv6_confirm(unsigned int hooknum,
struct sk_buff **pskb,
const struct net_device *in,
Expand Down Expand Up @@ -397,7 +392,6 @@ struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 = {
.ctl_table_path = nf_net_netfilter_sysctl_path,
.ctl_table = nf_ct_ipv6_sysctl_table,
#endif
.get_features = ipv6_get_features,
.me = THIS_MODULE,
};

Expand Down
222 changes: 15 additions & 207 deletions net/netfilter/nf_conntrack_core.c
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Original file line number Diff line number Diff line change
Expand Up @@ -71,39 +71,12 @@ EXPORT_SYMBOL_GPL(nf_conntrack_untracked);
unsigned int nf_ct_log_invalid __read_mostly;
LIST_HEAD(unconfirmed);
static int nf_conntrack_vmalloc __read_mostly;

static struct kmem_cache *nf_conntrack_cachep __read_mostly;
static unsigned int nf_conntrack_next_id;

DEFINE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
EXPORT_PER_CPU_SYMBOL(nf_conntrack_stat);

/*
* This scheme offers various size of "struct nf_conn" dependent on
* features(helper, nat, ...)
*/

#define NF_CT_FEATURES_NAMELEN 256
static struct {
/* name of slab cache. printed in /proc/slabinfo */
char *name;

/* size of slab cache */
size_t size;

/* slab cache pointer */
struct kmem_cache *cachep;

/* allocated slab cache + modules which uses this slab cache */
int use;

} nf_ct_cache[NF_CT_F_NUM];

/* protect members of nf_ct_cache except of "use" */
DEFINE_RWLOCK(nf_ct_cache_lock);

/* This avoids calling kmem_cache_create() with same name simultaneously */
static DEFINE_MUTEX(nf_ct_cache_mutex);

static int nf_conntrack_hash_rnd_initted;
static unsigned int nf_conntrack_hash_rnd;

Expand All @@ -126,122 +99,6 @@ static inline u_int32_t hash_conntrack(const struct nf_conntrack_tuple *tuple)
nf_conntrack_hash_rnd);
}

int nf_conntrack_register_cache(u_int32_t features, const char *name,
size_t size)
{
int ret = 0;
char *cache_name;
struct kmem_cache *cachep;

DEBUGP("nf_conntrack_register_cache: features=0x%x, name=%s, size=%d\n",
features, name, size);

if (features < NF_CT_F_BASIC || features >= NF_CT_F_NUM) {
DEBUGP("nf_conntrack_register_cache: invalid features.: 0x%x\n",
features);
return -EINVAL;
}

mutex_lock(&nf_ct_cache_mutex);

write_lock_bh(&nf_ct_cache_lock);
/* e.g: multiple helpers are loaded */
if (nf_ct_cache[features].use > 0) {
DEBUGP("nf_conntrack_register_cache: already resisterd.\n");
if ((!strncmp(nf_ct_cache[features].name, name,
NF_CT_FEATURES_NAMELEN))
&& nf_ct_cache[features].size == size) {
DEBUGP("nf_conntrack_register_cache: reusing.\n");
nf_ct_cache[features].use++;
ret = 0;
} else
ret = -EBUSY;

write_unlock_bh(&nf_ct_cache_lock);
mutex_unlock(&nf_ct_cache_mutex);
return ret;
}
write_unlock_bh(&nf_ct_cache_lock);

/*
* The memory space for name of slab cache must be alive until
* cache is destroyed.
*/
cache_name = kmalloc(sizeof(char)*NF_CT_FEATURES_NAMELEN, GFP_ATOMIC);
if (cache_name == NULL) {
DEBUGP("nf_conntrack_register_cache: can't alloc cache_name\n");
ret = -ENOMEM;
goto out_up_mutex;
}

if (strlcpy(cache_name, name, NF_CT_FEATURES_NAMELEN)
>= NF_CT_FEATURES_NAMELEN) {
printk("nf_conntrack_register_cache: name too long\n");
ret = -EINVAL;
goto out_free_name;
}

cachep = kmem_cache_create(cache_name, size, 0, 0,
NULL, NULL);
if (!cachep) {
printk("nf_conntrack_register_cache: Can't create slab cache "
"for the features = 0x%x\n", features);
ret = -ENOMEM;
goto out_free_name;
}

write_lock_bh(&nf_ct_cache_lock);
nf_ct_cache[features].use = 1;
nf_ct_cache[features].size = size;
nf_ct_cache[features].cachep = cachep;
nf_ct_cache[features].name = cache_name;
write_unlock_bh(&nf_ct_cache_lock);

goto out_up_mutex;

out_free_name:
kfree(cache_name);
out_up_mutex:
mutex_unlock(&nf_ct_cache_mutex);
return ret;
}
EXPORT_SYMBOL_GPL(nf_conntrack_register_cache);

/* FIXME: In the current, only nf_conntrack_cleanup() can call this function. */
void nf_conntrack_unregister_cache(u_int32_t features)
{
struct kmem_cache *cachep;
char *name;

/*
* This assures that kmem_cache_create() isn't called before destroying
* slab cache.
*/
DEBUGP("nf_conntrack_unregister_cache: 0x%04x\n", features);
mutex_lock(&nf_ct_cache_mutex);

write_lock_bh(&nf_ct_cache_lock);
if (--nf_ct_cache[features].use > 0) {
write_unlock_bh(&nf_ct_cache_lock);
mutex_unlock(&nf_ct_cache_mutex);
return;
}
cachep = nf_ct_cache[features].cachep;
name = nf_ct_cache[features].name;
nf_ct_cache[features].cachep = NULL;
nf_ct_cache[features].name = NULL;
nf_ct_cache[features].size = 0;
write_unlock_bh(&nf_ct_cache_lock);

synchronize_net();

kmem_cache_destroy(cachep);
kfree(name);

mutex_unlock(&nf_ct_cache_mutex);
}
EXPORT_SYMBOL_GPL(nf_conntrack_unregister_cache);

int
nf_ct_get_tuple(const struct sk_buff *skb,
unsigned int nhoff,
Expand Down Expand Up @@ -559,11 +416,8 @@ static int early_drop(struct list_head *chain)
return dropped;
}

static struct nf_conn *
__nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
const struct nf_conntrack_tuple *repl,
const struct nf_conntrack_l3proto *l3proto,
u_int32_t features)
struct nf_conn *nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
const struct nf_conntrack_tuple *repl)
{
struct nf_conn *conntrack = NULL;

Expand All @@ -589,65 +443,28 @@ __nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
}
}

/* find features needed by this conntrack. */
features |= l3proto->get_features(orig);

DEBUGP("nf_conntrack_alloc: features=0x%x\n", features);

read_lock_bh(&nf_ct_cache_lock);

if (unlikely(!nf_ct_cache[features].use)) {
DEBUGP("nf_conntrack_alloc: not supported features = 0x%x\n",
features);
goto out;
}

conntrack = kmem_cache_alloc(nf_ct_cache[features].cachep, GFP_ATOMIC);
conntrack = kmem_cache_zalloc(nf_conntrack_cachep, GFP_ATOMIC);
if (conntrack == NULL) {
DEBUGP("nf_conntrack_alloc: Can't alloc conntrack from cache\n");
goto out;
DEBUGP("nf_conntrack_alloc: Can't alloc conntrack.\n");
atomic_dec(&nf_conntrack_count);
return ERR_PTR(-ENOMEM);
}

memset(conntrack, 0, nf_ct_cache[features].size);
conntrack->features = features;
atomic_set(&conntrack->ct_general.use, 1);
conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig;
conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = *repl;
/* Don't set timer yet: wait for confirmation */
setup_timer(&conntrack->timeout, death_by_timeout,
(unsigned long)conntrack);
read_unlock_bh(&nf_ct_cache_lock);

return conntrack;
out:
read_unlock_bh(&nf_ct_cache_lock);
atomic_dec(&nf_conntrack_count);
return conntrack;
}

struct nf_conn *nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
const struct nf_conntrack_tuple *repl)
{
struct nf_conntrack_l3proto *l3proto;
struct nf_conn *ct;

rcu_read_lock();
l3proto = __nf_ct_l3proto_find(orig->src.l3num);
ct = __nf_conntrack_alloc(orig, repl, l3proto, 0);
rcu_read_unlock();

return ct;
}
EXPORT_SYMBOL_GPL(nf_conntrack_alloc);

void nf_conntrack_free(struct nf_conn *conntrack)
{
u_int32_t features = conntrack->features;
NF_CT_ASSERT(features >= NF_CT_F_BASIC && features < NF_CT_F_NUM);
nf_ct_ext_free(conntrack);
DEBUGP("nf_conntrack_free: features = 0x%x, conntrack=%p\n", features,
conntrack);
kmem_cache_free(nf_ct_cache[features].cachep, conntrack);
kmem_cache_free(nf_conntrack_cachep, conntrack);
atomic_dec(&nf_conntrack_count);
}
EXPORT_SYMBOL_GPL(nf_conntrack_free);
Expand All @@ -665,14 +482,13 @@ init_conntrack(const struct nf_conntrack_tuple *tuple,
struct nf_conn_help *help;
struct nf_conntrack_tuple repl_tuple;
struct nf_conntrack_expect *exp;
u_int32_t features = 0;

if (!nf_ct_invert_tuple(&repl_tuple, tuple, l3proto, l4proto)) {
DEBUGP("Can't invert tuple.\n");
return NULL;
}

conntrack = __nf_conntrack_alloc(tuple, &repl_tuple, l3proto, features);
conntrack = nf_conntrack_alloc(tuple, &repl_tuple);
if (conntrack == NULL || IS_ERR(conntrack)) {
DEBUGP("Can't allocate conntrack.\n");
return (struct nf_conntrack_tuple_hash *)conntrack;
Expand Down Expand Up @@ -1128,8 +944,6 @@ EXPORT_SYMBOL_GPL(nf_conntrack_flush);
supposed to kill the mall. */
void nf_conntrack_cleanup(void)
{
int i;

rcu_assign_pointer(ip_ct_attach, NULL);

/* This makes sure all current packets have passed through
Expand All @@ -1150,14 +964,7 @@ void nf_conntrack_cleanup(void)

rcu_assign_pointer(nf_ct_destroy, NULL);

for (i = 0; i < NF_CT_F_NUM; i++) {
if (nf_ct_cache[i].use == 0)
continue;

NF_CT_ASSERT(nf_ct_cache[i].use == 1);
nf_ct_cache[i].use = 1;
nf_conntrack_unregister_cache(i);
}
kmem_cache_destroy(nf_conntrack_cachep);
kmem_cache_destroy(nf_conntrack_expect_cachep);
free_conntrack_hash(nf_conntrack_hash, nf_conntrack_vmalloc,
nf_conntrack_htable_size);
Expand Down Expand Up @@ -1267,9 +1074,10 @@ int __init nf_conntrack_init(void)
goto err_out;
}

ret = nf_conntrack_register_cache(NF_CT_F_BASIC, "nf_conntrack:basic",
sizeof(struct nf_conn));
if (ret < 0) {
nf_conntrack_cachep = kmem_cache_create("nf_conntrack",
sizeof(struct nf_conn),
0, 0, NULL, NULL);
if (!nf_conntrack_cachep) {
printk(KERN_ERR "Unable to create nf_conn slab cache\n");
goto err_free_hash;
}
Expand Down Expand Up @@ -1307,7 +1115,7 @@ int __init nf_conntrack_init(void)
out_free_expect_slab:
kmem_cache_destroy(nf_conntrack_expect_cachep);
err_free_conntrack_slab:
nf_conntrack_unregister_cache(NF_CT_F_BASIC);
kmem_cache_destroy(nf_conntrack_cachep);
err_free_hash:
free_conntrack_hash(nf_conntrack_hash, nf_conntrack_vmalloc,
nf_conntrack_htable_size);
Expand Down
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