static int __net_init ipv4_frags_init_net(struct net *net) { int res; /* Fragment cache limits. * * The fragment memory accounting code, (tries to) account for * the real memory usage, by measuring both the size of frag * queue struct (inet_frag_queue (ipv4:ipq/ipv6:frag_queue)) * and the SKB's truesize. * * A 64K fragment consumes 129736 bytes (44*2944)+200 * (1500 truesize == 2944, sizeof(struct ipq) == 200) * * We will commit 4MB at one time. Should we cross that limit * we will prune down to 3MB, making room for approx 8 big 64K * fragments 8x128k. */ net->ipv4.frags.high_thresh = 4 * 1024 * 1024; net->ipv4.frags.low_thresh = 3 * 1024 * 1024; /* * Important NOTE! Fragment queue must be destroyed before MSL expires. * RFC791 is wrong proposing to prolongate timer each fragment arrival * by TTL. */ net->ipv4.frags.timeout = IP_FRAG_TIME; res = inet_frags_init_net(&net->ipv4.frags); if (res) return res; res = ip4_frags_ns_ctl_register(net); if (res) inet_frags_uninit_net(&net->ipv4.frags); return res; }
static int __net_init ipv6_frags_init_net(struct net *net) { int res; net->ipv6.frags.high_thresh = IPV6_FRAG_HIGH_THRESH; net->ipv6.frags.low_thresh = IPV6_FRAG_LOW_THRESH; net->ipv6.frags.timeout = IPV6_FRAG_TIMEOUT; res = inet_frags_init_net(&net->ipv6.frags); if (res) return res; res = ip6_frags_ns_sysctl_register(net); if (res) inet_frags_uninit_net(&net->ipv6.frags); return res; }