From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/net/bridge/netfilter/ebt_limit.c | 127 ++++++++++++++++++++++++++++++++ 1 file changed, 127 insertions(+) create mode 100644 kernel/net/bridge/netfilter/ebt_limit.c (limited to 'kernel/net/bridge/netfilter/ebt_limit.c') diff --git a/kernel/net/bridge/netfilter/ebt_limit.c b/kernel/net/bridge/netfilter/ebt_limit.c new file mode 100644 index 000000000..517e78bef --- /dev/null +++ b/kernel/net/bridge/netfilter/ebt_limit.c @@ -0,0 +1,127 @@ +/* + * ebt_limit + * + * Authors: + * Tom Marshall + * + * Mostly copied from netfilter's ipt_limit.c, see that file for + * more explanation + * + * September, 2003 + * + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include +#include +#include +#include +#include +#include + +static DEFINE_SPINLOCK(limit_lock); + +#define MAX_CPJ (0xFFFFFFFF / (HZ*60*60*24)) + +#define _POW2_BELOW2(x) ((x)|((x)>>1)) +#define _POW2_BELOW4(x) (_POW2_BELOW2(x)|_POW2_BELOW2((x)>>2)) +#define _POW2_BELOW8(x) (_POW2_BELOW4(x)|_POW2_BELOW4((x)>>4)) +#define _POW2_BELOW16(x) (_POW2_BELOW8(x)|_POW2_BELOW8((x)>>8)) +#define _POW2_BELOW32(x) (_POW2_BELOW16(x)|_POW2_BELOW16((x)>>16)) +#define POW2_BELOW32(x) ((_POW2_BELOW32(x)>>1) + 1) + +#define CREDITS_PER_JIFFY POW2_BELOW32(MAX_CPJ) + +static bool +ebt_limit_mt(const struct sk_buff *skb, struct xt_action_param *par) +{ + struct ebt_limit_info *info = (void *)par->matchinfo; + unsigned long now = jiffies; + + spin_lock_bh(&limit_lock); + info->credit += (now - xchg(&info->prev, now)) * CREDITS_PER_JIFFY; + if (info->credit > info->credit_cap) + info->credit = info->credit_cap; + + if (info->credit >= info->cost) { + /* We're not limited. */ + info->credit -= info->cost; + spin_unlock_bh(&limit_lock); + return true; + } + + spin_unlock_bh(&limit_lock); + return false; +} + +/* Precision saver. */ +static u_int32_t +user2credits(u_int32_t user) +{ + /* If multiplying would overflow... */ + if (user > 0xFFFFFFFF / (HZ*CREDITS_PER_JIFFY)) + /* Divide first. */ + return (user / EBT_LIMIT_SCALE) * HZ * CREDITS_PER_JIFFY; + + return (user * HZ * CREDITS_PER_JIFFY) / EBT_LIMIT_SCALE; +} + +static int ebt_limit_mt_check(const struct xt_mtchk_param *par) +{ + struct ebt_limit_info *info = par->matchinfo; + + /* Check for overflow. */ + if (info->burst == 0 || + user2credits(info->avg * info->burst) < user2credits(info->avg)) { + pr_info("overflow, try lower: %u/%u\n", + info->avg, info->burst); + return -EINVAL; + } + + /* User avg in seconds * EBT_LIMIT_SCALE: convert to jiffies * 128. */ + info->prev = jiffies; + info->credit = user2credits(info->avg * info->burst); + info->credit_cap = user2credits(info->avg * info->burst); + info->cost = user2credits(info->avg); + return 0; +} + + +#ifdef CONFIG_COMPAT +/* + * no conversion function needed -- + * only avg/burst have meaningful values in userspace. + */ +struct ebt_compat_limit_info { + compat_uint_t avg, burst; + compat_ulong_t prev; + compat_uint_t credit, credit_cap, cost; +}; +#endif + +static struct xt_match ebt_limit_mt_reg __read_mostly = { + .name = "limit", + .revision = 0, + .family = NFPROTO_BRIDGE, + .match = ebt_limit_mt, + .checkentry = ebt_limit_mt_check, + .matchsize = sizeof(struct ebt_limit_info), +#ifdef CONFIG_COMPAT + .compatsize = sizeof(struct ebt_compat_limit_info), +#endif + .me = THIS_MODULE, +}; + +static int __init ebt_limit_init(void) +{ + return xt_register_match(&ebt_limit_mt_reg); +} + +static void __exit ebt_limit_fini(void) +{ + xt_unregister_match(&ebt_limit_mt_reg); +} + +module_init(ebt_limit_init); +module_exit(ebt_limit_fini); +MODULE_DESCRIPTION("Ebtables: Rate-limit match"); +MODULE_LICENSE("GPL"); -- cgit 1.2.3-korg