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/netlink.h>
24#include <net/gen_stats.h>
25
26
27static inline int
28gnet_stats_copy(struct gnet_dump *d, int type, void *buf, int size)
29{
30	if (nla_put(d->skb, type, size, buf))
31		goto nla_put_failure;
32	return 0;
33
34nla_put_failure:
35	spin_unlock_bh(d->lock);
36	return -1;
37}
38
39/**
40 * gnet_stats_start_copy_compat - start dumping procedure in compatibility mode
41 * @skb: socket buffer to put statistics TLVs into
42 * @type: TLV type for top level statistic TLV
43 * @tc_stats_type: TLV type for backward compatibility struct tc_stats TLV
44 * @xstats_type: TLV type for backward compatibility xstats TLV
45 * @lock: statistics lock
46 * @d: dumping handle
47 *
48 * Initializes the dumping handle, grabs the statistic lock and appends
49 * an empty TLV header to the socket buffer for use a container for all
50 * other statistic TLVS.
51 *
52 * The dumping handle is marked to be in backward compatibility mode telling
53 * all gnet_stats_copy_XXX() functions to fill a local copy of struct tc_stats.
54 *
55 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient.
56 */
57int
58gnet_stats_start_copy_compat(struct sk_buff *skb, int type, int tc_stats_type,
59	int xstats_type, spinlock_t *lock, struct gnet_dump *d)
60	__acquires(lock)
61{
62	memset(d, 0, sizeof(*d));
63
64	spin_lock_bh(lock);
65	d->lock = lock;
66	if (type)
67		d->tail = (struct nlattr *)skb_tail_pointer(skb);
68	d->skb = skb;
69	d->compat_tc_stats = tc_stats_type;
70	d->compat_xstats = xstats_type;
71
72	if (d->tail)
73		return gnet_stats_copy(d, type, NULL, 0);
74
75	return 0;
76}
77EXPORT_SYMBOL(gnet_stats_start_copy_compat);
78
79/**
80 * gnet_stats_start_copy_compat - start dumping procedure in compatibility mode
81 * @skb: socket buffer to put statistics TLVs into
82 * @type: TLV type for top level statistic TLV
83 * @lock: statistics lock
84 * @d: dumping handle
85 *
86 * Initializes the dumping handle, grabs the statistic lock and appends
87 * an empty TLV header to the socket buffer for use a container for all
88 * other statistic TLVS.
89 *
90 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient.
91 */
92int
93gnet_stats_start_copy(struct sk_buff *skb, int type, spinlock_t *lock,
94	struct gnet_dump *d)
95{
96	return gnet_stats_start_copy_compat(skb, type, 0, 0, lock, d);
97}
98EXPORT_SYMBOL(gnet_stats_start_copy);
99
100/**
101 * gnet_stats_copy_basic - copy basic statistics into statistic TLV
102 * @d: dumping handle
103 * @b: basic statistics
104 *
105 * Appends the basic statistics to the top level TLV created by
106 * gnet_stats_start_copy().
107 *
108 * Returns 0 on success or -1 with the statistic lock released
109 * if the room in the socket buffer was not sufficient.
110 */
111int
112gnet_stats_copy_basic(struct gnet_dump *d, struct gnet_stats_basic_packed *b)
113{
114	if (d->compat_tc_stats) {
115		d->tc_stats.bytes = b->bytes;
116		d->tc_stats.packets = b->packets;
117	}
118
119	if (d->tail) {
120		struct gnet_stats_basic sb;
121
122		memset(&sb, 0, sizeof(sb));
123		sb.bytes = b->bytes;
124		sb.packets = b->packets;
125		return gnet_stats_copy(d, TCA_STATS_BASIC, &sb, sizeof(sb));
126	}
127	return 0;
128}
129EXPORT_SYMBOL(gnet_stats_copy_basic);
130
131/**
132 * gnet_stats_copy_rate_est - copy rate estimator statistics into statistics TLV
133 * @d: dumping handle
134 * @b: basic statistics
135 * @r: rate estimator statistics
136 *
137 * Appends the rate estimator statistics to the top level TLV created by
138 * gnet_stats_start_copy().
139 *
140 * Returns 0 on success or -1 with the statistic lock released
141 * if the room in the socket buffer was not sufficient.
142 */
143int
144gnet_stats_copy_rate_est(struct gnet_dump *d,
145			 const struct gnet_stats_basic_packed *b,
146			 struct gnet_stats_rate_est *r)
147{
148	if (b && !gen_estimator_active(b, r))
149		return 0;
150
151	if (d->compat_tc_stats) {
152		d->tc_stats.bps = r->bps;
153		d->tc_stats.pps = r->pps;
154	}
155
156	if (d->tail)
157		return gnet_stats_copy(d, TCA_STATS_RATE_EST, r, sizeof(*r));
158
159	return 0;
160}
161EXPORT_SYMBOL(gnet_stats_copy_rate_est);
162
163/**
164 * gnet_stats_copy_queue - copy queue statistics into statistics TLV
165 * @d: dumping handle
166 * @q: queue statistics
167 *
168 * Appends the queue statistics to the top level TLV created by
169 * gnet_stats_start_copy().
170 *
171 * Returns 0 on success or -1 with the statistic lock released
172 * if the room in the socket buffer was not sufficient.
173 */
174int
175gnet_stats_copy_queue(struct gnet_dump *d, struct gnet_stats_queue *q)
176{
177	if (d->compat_tc_stats) {
178		d->tc_stats.drops = q->drops;
179		d->tc_stats.qlen = q->qlen;
180		d->tc_stats.backlog = q->backlog;
181		d->tc_stats.overlimits = q->overlimits;
182	}
183
184	if (d->tail)
185		return gnet_stats_copy(d, TCA_STATS_QUEUE, q, sizeof(*q));
186
187	return 0;
188}
189EXPORT_SYMBOL(gnet_stats_copy_queue);
190
191/**
192 * gnet_stats_copy_app - copy application specific statistics into statistics TLV
193 * @d: dumping handle
194 * @st: application specific statistics data
195 * @len: length of data
196 *
197 * Appends the application sepecific statistics to the top level TLV created by
198 * gnet_stats_start_copy() and remembers the data for XSTATS if the dumping
199 * handle is in backward compatibility mode.
200 *
201 * Returns 0 on success or -1 with the statistic lock released
202 * if the room in the socket buffer was not sufficient.
203 */
204int
205gnet_stats_copy_app(struct gnet_dump *d, void *st, int len)
206{
207	if (d->compat_xstats) {
208		d->xstats = st;
209		d->xstats_len = len;
210	}
211
212	if (d->tail)
213		return gnet_stats_copy(d, TCA_STATS_APP, st, len);
214
215	return 0;
216}
217EXPORT_SYMBOL(gnet_stats_copy_app);
218
219/**
220 * gnet_stats_finish_copy - finish dumping procedure
221 * @d: dumping handle
222 *
223 * Corrects the length of the top level TLV to include all TLVs added
224 * by gnet_stats_copy_XXX() calls. Adds the backward compatibility TLVs
225 * if gnet_stats_start_copy_compat() was used and releases the statistics
226 * lock.
227 *
228 * Returns 0 on success or -1 with the statistic lock released
229 * if the room in the socket buffer was not sufficient.
230 */
231int
232gnet_stats_finish_copy(struct gnet_dump *d)
233{
234	if (d->tail)
235		d->tail->nla_len = skb_tail_pointer(d->skb) - (u8 *)d->tail;
236
237	if (d->compat_tc_stats)
238		if (gnet_stats_copy(d, d->compat_tc_stats, &d->tc_stats,
239			sizeof(d->tc_stats)) < 0)
240			return -1;
241
242	if (d->compat_xstats && d->xstats) {
243		if (gnet_stats_copy(d, d->compat_xstats, d->xstats,
244			d->xstats_len) < 0)
245			return -1;
246	}
247
248	spin_unlock_bh(d->lock);
249	return 0;
250}
251EXPORT_SYMBOL(gnet_stats_finish_copy);
252