diff options
Diffstat (limited to 'net/ipv4/tcp.c')
| -rw-r--r-- | net/ipv4/tcp.c | 34 |
1 files changed, 24 insertions, 10 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 0f8caf64caa3..296150b2a62f 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2839,7 +2839,6 @@ static void __tcp_free_md5sig_pool(struct tcp_md5sig_pool * __percpu *pool) if (p->md5_desc.tfm) crypto_free_hash(p->md5_desc.tfm); kfree(p); - p = NULL; } } free_percpu(pool); @@ -2937,25 +2936,40 @@ retry: EXPORT_SYMBOL(tcp_alloc_md5sig_pool); -struct tcp_md5sig_pool *__tcp_get_md5sig_pool(int cpu) + +/** + * tcp_get_md5sig_pool - get md5sig_pool for this user + * + * We use percpu structure, so if we succeed, we exit with preemption + * and BH disabled, to make sure another thread or softirq handling + * wont try to get same context. + */ +struct tcp_md5sig_pool *tcp_get_md5sig_pool(void) { struct tcp_md5sig_pool * __percpu *p; - spin_lock_bh(&tcp_md5sig_pool_lock); + + local_bh_disable(); + + spin_lock(&tcp_md5sig_pool_lock); p = tcp_md5sig_pool; if (p) tcp_md5sig_users++; - spin_unlock_bh(&tcp_md5sig_pool_lock); - return (p ? *per_cpu_ptr(p, cpu) : NULL); -} + spin_unlock(&tcp_md5sig_pool_lock); + + if (p) + return *per_cpu_ptr(p, smp_processor_id()); -EXPORT_SYMBOL(__tcp_get_md5sig_pool); + local_bh_enable(); + return NULL; +} +EXPORT_SYMBOL(tcp_get_md5sig_pool); -void __tcp_put_md5sig_pool(void) +void tcp_put_md5sig_pool(void) { + local_bh_enable(); tcp_free_md5sig_pool(); } - -EXPORT_SYMBOL(__tcp_put_md5sig_pool); +EXPORT_SYMBOL(tcp_put_md5sig_pool); int tcp_md5_hash_header(struct tcp_md5sig_pool *hp, struct tcphdr *th) |