From fbc907f0b1386c02e00516aa78a0fa6b0454fd0b Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Fri, 28 Mar 2014 18:58:20 +0100 Subject: [PATCH] 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 Signed-off-by: Alexei Starovoitov Cc: Pavel Emelyanov Signed-off-by: David S. Miller --- include/linux/filter.h | 30 +++++++++++++++++------------- include/net/sock.h | 27 --------------------------- net/core/filter.c | 27 +++++++++++++++++++++++++-- 3 files changed, 42 insertions(+), 42 deletions(-) diff --git a/include/linux/filter.h b/include/linux/filter.h index 93a9792e27bc..9bde3ed19fe6 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -50,28 +50,32 @@ static inline unsigned int sk_filter_size(unsigned int proglen) #define sk_filter_proglen(fprog) \ (fprog->len * sizeof(fprog->filter[0])) -extern int sk_filter(struct sock *sk, struct sk_buff *skb); -extern unsigned int sk_run_filter(const struct sk_buff *skb, - const struct sock_filter *filter); +int sk_filter(struct sock *sk, struct sk_buff *skb); +unsigned int sk_run_filter(const struct sk_buff *skb, + const struct sock_filter *filter); -extern int sk_unattached_filter_create(struct sk_filter **pfp, - struct sock_fprog *fprog); -extern void sk_unattached_filter_destroy(struct sk_filter *fp); +int sk_unattached_filter_create(struct sk_filter **pfp, + struct sock_fprog *fprog); +void sk_unattached_filter_destroy(struct sk_filter *fp); -extern int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk); -extern int sk_detach_filter(struct sock *sk); +int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk); +int sk_detach_filter(struct sock *sk); -extern int sk_chk_filter(struct sock_filter *filter, unsigned int flen); -extern int sk_get_filter(struct sock *sk, struct sock_filter __user *filter, unsigned len); -extern void sk_decode_filter(struct sock_filter *filt, struct sock_filter *to); +int sk_chk_filter(struct sock_filter *filter, unsigned int flen); +int sk_get_filter(struct sock *sk, struct sock_filter __user *filter, + unsigned int len); +void sk_decode_filter(struct sock_filter *filt, struct sock_filter *to); + +void sk_filter_charge(struct sock *sk, struct sk_filter *fp); +void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp); #ifdef CONFIG_BPF_JIT #include #include #include -extern void bpf_jit_compile(struct sk_filter *fp); -extern void bpf_jit_free(struct sk_filter *fp); +void bpf_jit_compile(struct sk_filter *fp); +void bpf_jit_free(struct sk_filter *fp); static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen, u32 pass, void *image) diff --git a/include/net/sock.h b/include/net/sock.h index 8d7c431a0660..06a5668f05c9 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1621,33 +1621,6 @@ void sk_common_release(struct sock *sk); /* Initialise core socket variables */ void sock_init_data(struct socket *sock, struct sock *sk); -void sk_filter_release_rcu(struct rcu_head *rcu); - -/** - * sk_filter_release - release a socket filter - * @fp: filter to remove - * - * Remove a filter from a socket and release its resources. - */ - -static inline void sk_filter_release(struct sk_filter *fp) -{ - if (atomic_dec_and_test(&fp->refcnt)) - call_rcu(&fp->rcu, sk_filter_release_rcu); -} - -static inline 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); -} - -static inline 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); -} - /* * Socket reference counting postulates. * diff --git a/net/core/filter.c b/net/core/filter.c index 9730e7fe4770..5b3427aaeca5 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_release_orig_filter(fp); bpf_jit_free(fp); } -EXPORT_SYMBOL(sk_filter_release_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) {