1/*
2 * net/core/gen_stats.c
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:  Thomas Graf <tgraf@suug.ch>
10 *           Jamal Hadi Salim
11 *           Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
12 *
13 * See Documentation/networking/gen_stats.txt
14 */
15
16#include <linux/types.h>
17#include <linux/kernel.h>
18#include <linux/module.h>
19#include <linux/interrupt.h>
20#include <linux/socket.h>
21#include <linux/rtnetlink.h>
22#include <linux/gen_stats.h>
23#include <net/gen_stats.h>
24
25
26static inline int
27gnet_stats_copy(struct gnet_dump *d, int type, void *buf, int size)
28{
29	RTA_PUT(d->skb, type, size, buf);
30	return 0;
31
32rtattr_failure:
33	spin_unlock_bh(d->lock);
34	return -1;
35}
36
37/**
38 * gnet_stats_start_copy_compat - start dumping procedure in compatibility mode
39 * @skb: socket buffer to put statistics TLVs into
40 * @type: TLV type for top level statistic TLV
41 * @tc_stats_type: TLV type for backward compatibility struct tc_stats TLV
42 * @xstats_type: TLV type for backward compatibility xstats TLV
43 * @lock: statistics lock
44 * @d: dumping handle
45 *
46 * Initializes the dumping handle, grabs the statistic lock and appends
47 * an empty TLV header to the socket buffer for use a container for all
48 * other statistic TLVS.
49 *
50 * The dumping handle is marked to be in backward compatibility mode telling
51 * all gnet_stats_copy_XXX() functions to fill a local copy of struct tc_stats.
52 *
53 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient.
54 */
55int
56gnet_stats_start_copy_compat(struct sk_buff *skb, int type, int tc_stats_type,
57	int xstats_type, spinlock_t *lock, struct gnet_dump *d)
58{
59	memset(d, 0, sizeof(*d));
60
61	spin_lock_bh(lock);
62	d->lock = lock;
63	if (type)
64		d->tail = (struct rtattr *)skb_tail_pointer(skb);
65	d->skb = skb;
66	d->compat_tc_stats = tc_stats_type;
67	d->compat_xstats = xstats_type;
68
69	if (d->tail)
70		return gnet_stats_copy(d, type, NULL, 0);
71
72	return 0;
73}
74
75/**
76 * gnet_stats_start_copy_compat - start dumping procedure in compatibility mode
77 * @skb: socket buffer to put statistics TLVs into
78 * @type: TLV type for top level statistic TLV
79 * @lock: statistics lock
80 * @d: dumping handle
81 *
82 * Initializes the dumping handle, grabs the statistic lock and appends
83 * an empty TLV header to the socket buffer for use a container for all
84 * other statistic TLVS.
85 *
86 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient.
87 */
88int
89gnet_stats_start_copy(struct sk_buff *skb, int type, spinlock_t *lock,
90	struct gnet_dump *d)
91{
92	return gnet_stats_start_copy_compat(skb, type, 0, 0, lock, d);
93}
94
95/**
96 * gnet_stats_copy_basic - copy basic statistics into statistic TLV
97 * @d: dumping handle
98 * @b: basic statistics
99 *
100 * Appends the basic statistics to the top level TLV created by
101 * gnet_stats_start_copy().
102 *
103 * Returns 0 on success or -1 with the statistic lock released
104 * if the room in the socket buffer was not sufficient.
105 */
106int
107gnet_stats_copy_basic(struct gnet_dump *d, struct gnet_stats_basic *b)
108{
109	if (d->compat_tc_stats) {
110		d->tc_stats.bytes = b->bytes;
111		d->tc_stats.packets = b->packets;
112	}
113
114	if (d->tail)
115		return gnet_stats_copy(d, TCA_STATS_BASIC, b, sizeof(*b));
116
117	return 0;
118}
119
120/**
121 * gnet_stats_copy_rate_est - copy rate estimator statistics into statistics TLV
122 * @d: dumping handle
123 * @r: rate estimator statistics
124 *
125 * Appends the rate estimator statistics to the top level TLV created by
126 * gnet_stats_start_copy().
127 *
128 * Returns 0 on success or -1 with the statistic lock released
129 * if the room in the socket buffer was not sufficient.
130 */
131int
132gnet_stats_copy_rate_est(struct gnet_dump *d, struct gnet_stats_rate_est *r)
133{
134	if (d->compat_tc_stats) {
135		d->tc_stats.bps = r->bps;
136		d->tc_stats.pps = r->pps;
137	}
138
139	if (d->tail)
140		return gnet_stats_copy(d, TCA_STATS_RATE_EST, r, sizeof(*r));
141
142	return 0;
143}
144
145/**
146 * gnet_stats_copy_queue - copy queue statistics into statistics TLV
147 * @d: dumping handle
148 * @q: queue statistics
149 *
150 * Appends the queue statistics to the top level TLV created by
151 * gnet_stats_start_copy().
152 *
153 * Returns 0 on success or -1 with the statistic lock released
154 * if the room in the socket buffer was not sufficient.
155 */
156int
157gnet_stats_copy_queue(struct gnet_dump *d, struct gnet_stats_queue *q)
158{
159	if (d->compat_tc_stats) {
160		d->tc_stats.drops = q->drops;
161		d->tc_stats.qlen = q->qlen;
162		d->tc_stats.backlog = q->backlog;
163		d->tc_stats.overlimits = q->overlimits;
164	}
165
166	if (d->tail)
167		return gnet_stats_copy(d, TCA_STATS_QUEUE, q, sizeof(*q));
168
169	return 0;
170}
171
172/**
173 * gnet_stats_copy_app - copy application specific statistics into statistics TLV
174 * @d: dumping handle
175 * @st: application specific statistics data
176 * @len: length of data
177 *
178 * Appends the application sepecific statistics to the top level TLV created by
179 * gnet_stats_start_copy() and remembers the data for XSTATS if the dumping
180 * handle is in backward compatibility mode.
181 *
182 * Returns 0 on success or -1 with the statistic lock released
183 * if the room in the socket buffer was not sufficient.
184 */
185int
186gnet_stats_copy_app(struct gnet_dump *d, void *st, int len)
187{
188	if (d->compat_xstats) {
189		d->xstats = st;
190		d->xstats_len = len;
191	}
192
193	if (d->tail)
194		return gnet_stats_copy(d, TCA_STATS_APP, st, len);
195
196	return 0;
197}
198
199/**
200 * gnet_stats_finish_copy - finish dumping procedure
201 * @d: dumping handle
202 *
203 * Corrects the length of the top level TLV to include all TLVs added
204 * by gnet_stats_copy_XXX() calls. Adds the backward compatibility TLVs
205 * if gnet_stats_start_copy_compat() was used and releases the statistics
206 * lock.
207 *
208 * Returns 0 on success or -1 with the statistic lock released
209 * if the room in the socket buffer was not sufficient.
210 */
211int
212gnet_stats_finish_copy(struct gnet_dump *d)
213{
214	if (d->tail)
215		d->tail->rta_len = skb_tail_pointer(d->skb) - (u8 *)d->tail;
216
217	if (d->compat_tc_stats)
218		if (gnet_stats_copy(d, d->compat_tc_stats, &d->tc_stats,
219			sizeof(d->tc_stats)) < 0)
220			return -1;
221
222	if (d->compat_xstats && d->xstats) {
223		if (gnet_stats_copy(d, d->compat_xstats, d->xstats,
224			d->xstats_len) < 0)
225			return -1;
226	}
227
228	spin_unlock_bh(d->lock);
229	return 0;
230}
231
232
233EXPORT_SYMBOL(gnet_stats_start_copy);
234EXPORT_SYMBOL(gnet_stats_start_copy_compat);
235EXPORT_SYMBOL(gnet_stats_copy_basic);
236EXPORT_SYMBOL(gnet_stats_copy_rate_est);
237EXPORT_SYMBOL(gnet_stats_copy_queue);
238EXPORT_SYMBOL(gnet_stats_copy_app);
239EXPORT_SYMBOL(gnet_stats_finish_copy);
240