4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Florian Westphal fw@strlen.de
commit f28e15bacedd444608e25421c72eb2cf4527c9ca upstream.
Keeps some noise away from a followup patch.
Signed-off-by: Florian Westphal fw@strlen.de Acked-by: Eric Dumazet edumazet@google.com Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- include/linux/netfilter/x_tables.h | 27 +-------------------------- net/ipv4/netfilter/arp_tables.c | 5 +---- net/ipv4/netfilter/ip_tables.c | 5 +---- net/ipv6/netfilter/ip6_tables.c | 5 +---- net/netfilter/x_tables.c | 30 ++++++++++++++++++++++++++++++ 5 files changed, 34 insertions(+), 38 deletions(-)
--- a/include/linux/netfilter/x_tables.h +++ b/include/linux/netfilter/x_tables.h @@ -369,32 +369,7 @@ static inline unsigned long ifname_compa }
-/* On SMP, ip(6)t_entry->counters.pcnt holds address of the - * real (percpu) counter. On !SMP, its just the packet count, - * so nothing needs to be done there. - * - * xt_percpu_counter_alloc returns the address of the percpu - * counter, or 0 on !SMP. We force an alignment of 16 bytes - * so that bytes/packets share a common cache line. - * - * Hence caller must use IS_ERR_VALUE to check for error, this - * allows us to return 0 for single core systems without forcing - * callers to deal with SMP vs. NONSMP issues. - */ -static inline unsigned long xt_percpu_counter_alloc(void) -{ - if (nr_cpu_ids > 1) { - void __percpu *res = __alloc_percpu(sizeof(struct xt_counters), - sizeof(struct xt_counters)); - - if (res == NULL) - return -ENOMEM; - - return (__force unsigned long) res; - } - - return 0; -} +bool xt_percpu_counter_alloc(struct xt_counters *counters); void xt_percpu_counter_free(struct xt_counters *cnt);
static inline struct xt_counters * --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -515,13 +515,10 @@ find_check_entry(struct arpt_entry *e, c { struct xt_entry_target *t; struct xt_target *target; - unsigned long pcnt; int ret;
- pcnt = xt_percpu_counter_alloc(); - if (IS_ERR_VALUE(pcnt)) + if (!xt_percpu_counter_alloc(&e->counters)) return -ENOMEM; - e->counters.pcnt = pcnt;
t = arpt_get_target(e); target = xt_request_find_target(NFPROTO_ARP, t->u.user.name, --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -657,12 +657,9 @@ find_check_entry(struct ipt_entry *e, st unsigned int j; struct xt_mtchk_param mtpar; struct xt_entry_match *ematch; - unsigned long pcnt;
- pcnt = xt_percpu_counter_alloc(); - if (IS_ERR_VALUE(pcnt)) + if (!xt_percpu_counter_alloc(&e->counters)) return -ENOMEM; - e->counters.pcnt = pcnt;
j = 0; mtpar.net = net; --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -670,12 +670,9 @@ find_check_entry(struct ip6t_entry *e, s unsigned int j; struct xt_mtchk_param mtpar; struct xt_entry_match *ematch; - unsigned long pcnt;
- pcnt = xt_percpu_counter_alloc(); - if (IS_ERR_VALUE(pcnt)) + if (!xt_percpu_counter_alloc(&e->counters)) return -ENOMEM; - e->counters.pcnt = pcnt;
j = 0; mtpar.net = net; --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -1592,6 +1592,36 @@ void xt_proto_fini(struct net *net, u_in } EXPORT_SYMBOL_GPL(xt_proto_fini);
+/** + * xt_percpu_counter_alloc - allocate x_tables rule counter + * + * @counter: pointer to counter struct inside the ip(6)/arpt_entry struct + * + * On SMP, the packet counter [ ip(6)t_entry->counters.pcnt ] will then + * contain the address of the real (percpu) counter. + * + * Rule evaluation needs to use xt_get_this_cpu_counter() helper + * to fetch the real percpu counter. + * + * returns false on error. + */ +bool xt_percpu_counter_alloc(struct xt_counters *counter) +{ + void __percpu *res; + + if (nr_cpu_ids <= 1) + return true; + + res = __alloc_percpu(sizeof(struct xt_counters), + sizeof(struct xt_counters)); + if (!res) + return false; + + counter->pcnt = (__force unsigned long)res; + return true; +} +EXPORT_SYMBOL_GPL(xt_percpu_counter_alloc); + void xt_percpu_counter_free(struct xt_counters *counters) { unsigned long pcnt = counters->pcnt;