libnl 3.9.0
fifo.c
1/* SPDX-License-Identifier: LGPL-2.1-only */
2/*
3 * Copyright (c) 2003-2011 Thomas Graf <tgraf@suug.ch>
4 */
5
6/**
7 * @ingroup qdisc
8 * @defgroup qdisc_fifo Packet/Bytes FIFO (pfifo/bfifo)
9 * @brief
10 *
11 * The FIFO qdisc comes in two flavours:
12 * @par bfifo (Byte FIFO)
13 * Allows enqueuing until the currently queued volume in bytes exceeds
14 * the configured limit.backlog contains currently enqueued volume in bytes.
15 *
16 * @par pfifo (Packet FIFO)
17 * Allows enquueing until the currently queued number of packets
18 * exceeds the configured limit.
19 *
20 * The configuration is exactly the same, the decision which of
21 * the two variations is going to be used is made based on the
22 * kind of the qdisc (rtnl_tc_set_kind()).
23 * @{
24 */
25
26#include "nl-default.h"
27
28#include <netlink/netlink.h>
29#include <netlink/route/qdisc.h>
30#include <netlink/route/qdisc/fifo.h>
31#include <netlink/utils.h>
32
33#include "tc-api.h"
34
35/** @cond SKIP */
36struct rtnl_fifo {
37 uint32_t qf_limit;
38 uint32_t qf_mask;
39};
40
41#define SCH_FIFO_ATTR_LIMIT 1
42/** @endcond */
43
44static int fifo_msg_parser(struct rtnl_tc *tc, void *data)
45{
46 struct rtnl_fifo *fifo = data;
47 struct tc_fifo_qopt *opt;
48
49 if (tc->tc_opts->d_size < sizeof(struct tc_fifo_qopt))
50 return -NLE_INVAL;
51
52 opt = (struct tc_fifo_qopt *) tc->tc_opts->d_data;
53 fifo->qf_limit = opt->limit;
54 fifo->qf_mask = SCH_FIFO_ATTR_LIMIT;
55
56 return 0;
57}
58
59static void pfifo_dump_line(struct rtnl_tc *tc, void *data,
60 struct nl_dump_params *p)
61{
62 struct rtnl_fifo *fifo = data;
63
64 if (fifo)
65 nl_dump(p, " limit %u packets", fifo->qf_limit);
66}
67
68static void bfifo_dump_line(struct rtnl_tc *tc, void *data,
69 struct nl_dump_params *p)
70{
71 struct rtnl_fifo *fifo = data;
72 char *unit;
73 double r;
74
75 if (!fifo)
76 return;
77
78 r = nl_cancel_down_bytes(fifo->qf_limit, &unit);
79 nl_dump(p, " limit %.1f%s", r, unit);
80}
81
82static int fifo_msg_fill(struct rtnl_tc *tc, void *data, struct nl_msg *msg)
83{
84 struct rtnl_fifo *fifo = data;
85 struct tc_fifo_qopt opts = {0};
86
87 if (!fifo || !(fifo->qf_mask & SCH_FIFO_ATTR_LIMIT))
88 return -NLE_INVAL;
89
90 opts.limit = fifo->qf_limit;
91
92 return nlmsg_append(msg, &opts, sizeof(opts), NL_DONTPAD);
93}
94
95/**
96 * @name Attribute Modification
97 * @{
98 */
99
100/**
101 * Set limit of FIFO qdisc.
102 * @arg qdisc FIFO qdisc to be modified.
103 * @arg limit New limit.
104 * @return 0 on success or a negative error code.
105 */
106int rtnl_qdisc_fifo_set_limit(struct rtnl_qdisc *qdisc, int limit)
107{
108 struct rtnl_fifo *fifo;
109
110 if (!(fifo = rtnl_tc_data(TC_CAST(qdisc))))
111 return -NLE_NOMEM;
112
113 fifo->qf_limit = limit;
114 fifo->qf_mask |= SCH_FIFO_ATTR_LIMIT;
115
116 return 0;
117}
118
119/**
120 * Get limit of a FIFO qdisc.
121 * @arg qdisc FIFO qdisc.
122 * @return Numeric limit or a negative error code.
123 */
125{
126 struct rtnl_fifo *fifo;
127
128 if (!(fifo = rtnl_tc_data(TC_CAST(qdisc))))
129 return -NLE_NOMEM;
130
131 if (fifo->qf_mask & SCH_FIFO_ATTR_LIMIT)
132 return fifo->qf_limit;
133 else
134 return -NLE_NOATTR;
135}
136
137/** @} */
138
139static struct rtnl_tc_ops pfifo_ops = {
140 .to_kind = "pfifo",
141 .to_type = RTNL_TC_TYPE_QDISC,
142 .to_size = sizeof(struct rtnl_fifo),
143 .to_msg_parser = fifo_msg_parser,
144 .to_dump[NL_DUMP_LINE] = pfifo_dump_line,
145 .to_msg_fill = fifo_msg_fill,
146};
147
148static struct rtnl_tc_ops bfifo_ops = {
149 .to_kind = "bfifo",
150 .to_type = RTNL_TC_TYPE_QDISC,
151 .to_size = sizeof(struct rtnl_fifo),
152 .to_msg_parser = fifo_msg_parser,
153 .to_dump[NL_DUMP_LINE] = bfifo_dump_line,
154 .to_msg_fill = fifo_msg_fill,
155};
156
157static void _nl_init fifo_init(void)
158{
159 rtnl_tc_register(&pfifo_ops);
160 rtnl_tc_register(&bfifo_ops);
161}
162
163static void _nl_exit fifo_exit(void)
164{
165 rtnl_tc_unregister(&pfifo_ops);
166 rtnl_tc_unregister(&bfifo_ops);
167}
168
169/** @} */
int nlmsg_append(struct nl_msg *n, void *data, size_t len, int pad)
Append data to tail of a netlink message.
Definition msg.c:450
int rtnl_qdisc_fifo_get_limit(struct rtnl_qdisc *qdisc)
Get limit of a FIFO qdisc.
Definition fifo.c:124
int rtnl_qdisc_fifo_set_limit(struct rtnl_qdisc *qdisc, int limit)
Set limit of FIFO qdisc.
Definition fifo.c:106
#define TC_CAST(ptr)
Macro to cast qdisc/class/classifier to tc object.
Definition tc.h:50
void * rtnl_tc_data(struct rtnl_tc *)
Return pointer to private data of traffic control object.
Definition tc.c:1079
int rtnl_tc_register(struct rtnl_tc_ops *)
Register a traffic control module.
Definition tc.c:1018
void rtnl_tc_unregister(struct rtnl_tc_ops *)
Unregister a traffic control module.
Definition tc.c:1052
void nl_dump(struct nl_dump_params *params, const char *fmt,...)
Dump a formatted character string.
Definition utils.c:1017
double nl_cancel_down_bytes(unsigned long long l, char **unit)
Cancel down a byte counter.
Definition utils.c:225
@ NL_DUMP_LINE
Dump object briefly on one line.
Definition types.h:20
Dumping parameters.
Definition types.h:32