path: root/net
diff options
authorDaniel Borkmann <dborkman@redhat.com>2014-03-28 18:58:20 +0100
committerDavid S. Miller <davem@davemloft.net>2014-03-31 00:45:09 -0400
commitfbc907f0b1386c02e00516aa78a0fa6b0454fd0b (patch)
treea747b5bb1dec44ce93e0924e4ea2de3411417b2c /net
parenta3ea269b8bcdbb0c5fa2fd449a436e7987446975 (diff)
net: filter: move filter accounting to filter core
This patch basically does two things, i) removes the extern keyword from the include/linux/filter.h file to be more consistent with the rest of Joe's changes, and ii) moves filter accounting into the filter core framework. Filter accounting mainly done through sk_filter_{un,}charge() take care of the case when sockets are being cloned through sk_clone_lock() so that removal of the filter on one socket won't result in eviction as it's still referenced by the other. These functions actually belong to net/core/filter.c and not include/net/sock.h as we want to keep all that in a central place. It's also not in fast-path so uninlining them is fine and even allows us to get rd of sk_filter_release_rcu()'s EXPORT_SYMBOL and a forward declaration. Joint work with Alexei Starovoitov. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
1 files changed, 25 insertions, 2 deletions
diff --git a/net/core/filter.c b/net/core/filter.c
index 9730e7fe477..5b3427aaeca 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -664,14 +664,37 @@ static void sk_release_orig_filter(struct sk_filter *fp)
* sk_filter_release_rcu - Release a socket filter by rcu_head
* @rcu: rcu_head that contains the sk_filter to free
-void sk_filter_release_rcu(struct rcu_head *rcu)
+static void sk_filter_release_rcu(struct rcu_head *rcu)
struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
+ * sk_filter_release - release a socket filter
+ * @fp: filter to remove
+ *
+ * Remove a filter from a socket and release its resources.
+ */
+static void sk_filter_release(struct sk_filter *fp)
+ if (atomic_dec_and_test(&fp->refcnt))
+ call_rcu(&fp->rcu, sk_filter_release_rcu);
+void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
+ atomic_sub(sk_filter_size(fp->len), &sk->sk_omem_alloc);
+ sk_filter_release(fp);
+void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
+ atomic_inc(&fp->refcnt);
+ atomic_add(sk_filter_size(fp->len), &sk->sk_omem_alloc);
static int __sk_prepare_filter(struct sk_filter *fp)