1/* SPDX-License-Identifier: GPL-2.0-only */
  2/*
  3 * Copyright (c) 2016 Qualcomm Atheros, Inc
  4 *
  5 * Based on net/sched/sch_fq_codel.c
  6 */
  7#ifndef __NET_SCHED_FQ_H
  8#define __NET_SCHED_FQ_H
  9
 10struct fq_tin;
 11
 12/**
 13 * struct fq_flow - per traffic flow queue
 14 *
 15 * @tin: owner of this flow. Used to manage collisions, i.e. when a packet
 16 *	hashes to an index which points to a flow that is already owned by a
 17 *	different tin the packet is destined to. In such case the implementer
 18 *	must provide a fallback flow
 19 * @flowchain: can be linked to fq_tin's new_flows or old_flows. Used for DRR++
 20 *	(deficit round robin) based round robin queuing similar to the one
 21 *	found in net/sched/sch_fq_codel.c
 22 * @queue: sk_buff queue to hold packets
 23 * @backlog: number of bytes pending in the queue. The number of packets can be
 24 *	found in @queue.qlen
 25 * @deficit: used for DRR++
 26 */
 27struct fq_flow {
 28	struct fq_tin *tin;
 29	struct list_head flowchain;
 30	struct sk_buff_head queue;
 31	u32 backlog;
 32	int deficit;
 33};
 34
 35/**
 36 * struct fq_tin - a logical container of fq_flows
 37 *
 38 * Used to group fq_flows into a logical aggregate. DRR++ scheme is used to
 39 * pull interleaved packets out of the associated flows.
 40 *
 41 * @new_flows: linked list of fq_flow
 42 * @old_flows: linked list of fq_flow
 43 */
 44struct fq_tin {
 45	struct list_head new_flows;
 46	struct list_head old_flows;
 47	struct list_head tin_list;
 48	struct fq_flow default_flow;
 49	u32 backlog_bytes;
 50	u32 backlog_packets;
 51	u32 overlimit;
 52	u32 collisions;
 53	u32 flows;
 54	u32 tx_bytes;
 55	u32 tx_packets;
 56};
 57
 58/**
 59 * struct fq - main container for fair queuing purposes
 60 *
 61 * @limit: max number of packets that can be queued across all flows
 62 * @backlog: number of packets queued across all flows
 63 */
 64struct fq {
 65	struct fq_flow *flows;
 66	unsigned long *flows_bitmap;
 67
 68	struct list_head tin_backlog;
 69	spinlock_t lock;
 70	u32 flows_cnt;
 71	u32 limit;
 72	u32 memory_limit;
 73	u32 memory_usage;
 74	u32 quantum;
 75	u32 backlog;
 76	u32 overlimit;
 77	u32 overmemory;
 78	u32 collisions;
 79};
 80
 81typedef struct sk_buff *fq_tin_dequeue_t(struct fq *,
 82					 struct fq_tin *,
 83					 struct fq_flow *flow);
 84
 85typedef void fq_skb_free_t(struct fq *,
 86			   struct fq_tin *,
 87			   struct fq_flow *,
 88			   struct sk_buff *);
 89
 90/* Return %true to filter (drop) the frame. */
 91typedef bool fq_skb_filter_t(struct fq *,
 92			     struct fq_tin *,
 93			     struct fq_flow *,
 94			     struct sk_buff *,
 95			     void *);
 96
 97typedef struct fq_flow *fq_flow_get_default_t(struct fq *,
 98					      struct fq_tin *,
 99					      int idx,
100					      struct sk_buff *);
101
102#endif