^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * net/dccp/qpolicy.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Policy-based packet dequeueing interface for DCCP.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Copyright (c) 2008 Tomasz Grobelny <tomasz@grobelny.oswiecenia.net>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include "dccp.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) * Simple Dequeueing Policy:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) * If tx_qlen is different from 0, enqueue up to tx_qlen elements.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) static void qpolicy_simple_push(struct sock *sk, struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) skb_queue_tail(&sk->sk_write_queue, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) static bool qpolicy_simple_full(struct sock *sk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) return dccp_sk(sk)->dccps_tx_qlen &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) sk->sk_write_queue.qlen >= dccp_sk(sk)->dccps_tx_qlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) static struct sk_buff *qpolicy_simple_top(struct sock *sk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) return skb_peek(&sk->sk_write_queue);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) * Priority-based Dequeueing Policy:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) * If tx_qlen is different from 0 and the queue has reached its upper bound
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) * of tx_qlen elements, replace older packets lowest-priority-first.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) static struct sk_buff *qpolicy_prio_best_skb(struct sock *sk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) struct sk_buff *skb, *best = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) skb_queue_walk(&sk->sk_write_queue, skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) if (best == NULL || skb->priority > best->priority)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) best = skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) return best;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) static struct sk_buff *qpolicy_prio_worst_skb(struct sock *sk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) struct sk_buff *skb, *worst = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) skb_queue_walk(&sk->sk_write_queue, skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) if (worst == NULL || skb->priority < worst->priority)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) worst = skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) return worst;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) static bool qpolicy_prio_full(struct sock *sk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) if (qpolicy_simple_full(sk))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) dccp_qpolicy_drop(sk, qpolicy_prio_worst_skb(sk));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) * struct dccp_qpolicy_operations - TX Packet Dequeueing Interface
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) * @push: add a new @skb to the write queue
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) * @full: indicates that no more packets will be admitted
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) * @top: peeks at whatever the queueing policy defines as its `top'
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) static struct dccp_qpolicy_operations {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) void (*push) (struct sock *sk, struct sk_buff *skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) bool (*full) (struct sock *sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) struct sk_buff* (*top) (struct sock *sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) __be32 params;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) } qpol_table[DCCPQ_POLICY_MAX] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) [DCCPQ_POLICY_SIMPLE] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) .push = qpolicy_simple_push,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) .full = qpolicy_simple_full,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) .top = qpolicy_simple_top,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) .params = 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) [DCCPQ_POLICY_PRIO] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) .push = qpolicy_simple_push,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) .full = qpolicy_prio_full,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) .top = qpolicy_prio_best_skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) .params = DCCP_SCM_PRIORITY,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) * Externally visible interface
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) void dccp_qpolicy_push(struct sock *sk, struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) qpol_table[dccp_sk(sk)->dccps_qpolicy].push(sk, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) bool dccp_qpolicy_full(struct sock *sk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) return qpol_table[dccp_sk(sk)->dccps_qpolicy].full(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) void dccp_qpolicy_drop(struct sock *sk, struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) if (skb != NULL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) skb_unlink(skb, &sk->sk_write_queue);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) kfree_skb(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) struct sk_buff *dccp_qpolicy_top(struct sock *sk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) return qpol_table[dccp_sk(sk)->dccps_qpolicy].top(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) struct sk_buff *dccp_qpolicy_pop(struct sock *sk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) struct sk_buff *skb = dccp_qpolicy_top(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) if (skb != NULL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) /* Clear any skb fields that we used internally */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) skb->priority = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) skb_unlink(skb, &sk->sk_write_queue);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) return skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) bool dccp_qpolicy_param_ok(struct sock *sk, __be32 param)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) /* check if exactly one bit is set */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) if (!param || (param & (param - 1)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) return (qpol_table[dccp_sk(sk)->dccps_qpolicy].params & param) == param;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) }
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
3 Commits
0 Branches
0 Tags