Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * net/sched/sch_fifo.c The simplest FIFO queue. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public License | |
6 | * as published by the Free Software Foundation; either version | |
7 | * 2 of the License, or (at your option) any later version. | |
8 | * | |
9 | * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> | |
10 | */ | |
11 | ||
1da177e4 | 12 | #include <linux/module.h> |
1da177e4 LT |
13 | #include <linux/types.h> |
14 | #include <linux/kernel.h> | |
1da177e4 | 15 | #include <linux/errno.h> |
1da177e4 | 16 | #include <linux/netdevice.h> |
1da177e4 | 17 | #include <linux/skbuff.h> |
1da177e4 LT |
18 | #include <net/pkt_sched.h> |
19 | ||
20 | /* 1 band FIFO pseudo-"scheduler" */ | |
21 | ||
22 | struct fifo_sched_data | |
23 | { | |
6fc8e84f | 24 | u32 limit; |
1da177e4 LT |
25 | }; |
26 | ||
6fc8e84f | 27 | static int bfifo_enqueue(struct sk_buff *skb, struct Qdisc* sch) |
1da177e4 LT |
28 | { |
29 | struct fifo_sched_data *q = qdisc_priv(sch); | |
30 | ||
aaae3013 TG |
31 | if (likely(sch->qstats.backlog + skb->len <= q->limit)) |
32 | return qdisc_enqueue_tail(skb, sch); | |
1da177e4 | 33 | |
aaae3013 | 34 | return qdisc_reshape_fail(skb, sch); |
1da177e4 LT |
35 | } |
36 | ||
6fc8e84f | 37 | static int pfifo_enqueue(struct sk_buff *skb, struct Qdisc* sch) |
1da177e4 LT |
38 | { |
39 | struct fifo_sched_data *q = qdisc_priv(sch); | |
40 | ||
aaae3013 TG |
41 | if (likely(skb_queue_len(&sch->q) < q->limit)) |
42 | return qdisc_enqueue_tail(skb, sch); | |
1da177e4 | 43 | |
aaae3013 | 44 | return qdisc_reshape_fail(skb, sch); |
1da177e4 LT |
45 | } |
46 | ||
47 | static int fifo_init(struct Qdisc *sch, struct rtattr *opt) | |
48 | { | |
49 | struct fifo_sched_data *q = qdisc_priv(sch); | |
50 | ||
51 | if (opt == NULL) { | |
6fc8e84f | 52 | u32 limit = sch->dev->tx_queue_len ? : 1; |
1da177e4 LT |
53 | |
54 | if (sch->ops == &bfifo_qdisc_ops) | |
6fc8e84f TG |
55 | limit *= sch->dev->mtu; |
56 | ||
57 | q->limit = limit; | |
1da177e4 LT |
58 | } else { |
59 | struct tc_fifo_qopt *ctl = RTA_DATA(opt); | |
6fc8e84f TG |
60 | |
61 | if (RTA_PAYLOAD(opt) < sizeof(*ctl)) | |
1da177e4 | 62 | return -EINVAL; |
6fc8e84f | 63 | |
1da177e4 LT |
64 | q->limit = ctl->limit; |
65 | } | |
6fc8e84f | 66 | |
1da177e4 LT |
67 | return 0; |
68 | } | |
69 | ||
70 | static int fifo_dump(struct Qdisc *sch, struct sk_buff *skb) | |
71 | { | |
72 | struct fifo_sched_data *q = qdisc_priv(sch); | |
6fc8e84f | 73 | struct tc_fifo_qopt opt = { .limit = q->limit }; |
1da177e4 | 74 | |
1da177e4 | 75 | RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt); |
1da177e4 LT |
76 | return skb->len; |
77 | ||
78 | rtattr_failure: | |
1da177e4 LT |
79 | return -1; |
80 | } | |
81 | ||
82 | struct Qdisc_ops pfifo_qdisc_ops = { | |
1da177e4 LT |
83 | .id = "pfifo", |
84 | .priv_size = sizeof(struct fifo_sched_data), | |
85 | .enqueue = pfifo_enqueue, | |
aaae3013 TG |
86 | .dequeue = qdisc_dequeue_head, |
87 | .requeue = qdisc_requeue, | |
88 | .drop = qdisc_queue_drop, | |
1da177e4 | 89 | .init = fifo_init, |
aaae3013 | 90 | .reset = qdisc_reset_queue, |
1da177e4 LT |
91 | .change = fifo_init, |
92 | .dump = fifo_dump, | |
93 | .owner = THIS_MODULE, | |
94 | }; | |
95 | ||
96 | struct Qdisc_ops bfifo_qdisc_ops = { | |
1da177e4 LT |
97 | .id = "bfifo", |
98 | .priv_size = sizeof(struct fifo_sched_data), | |
99 | .enqueue = bfifo_enqueue, | |
aaae3013 TG |
100 | .dequeue = qdisc_dequeue_head, |
101 | .requeue = qdisc_requeue, | |
102 | .drop = qdisc_queue_drop, | |
1da177e4 | 103 | .init = fifo_init, |
aaae3013 | 104 | .reset = qdisc_reset_queue, |
1da177e4 LT |
105 | .change = fifo_init, |
106 | .dump = fifo_dump, | |
107 | .owner = THIS_MODULE, | |
108 | }; | |
109 | ||
110 | EXPORT_SYMBOL(bfifo_qdisc_ops); | |
111 | EXPORT_SYMBOL(pfifo_qdisc_ops); |