1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2016 Netflix, Inc.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#ifndef __tcp_log_dev_h__
29#define __tcp_log_dev_h__
30
31/*
32 * This is the common header for data streamed from the log device. All
33 * blocks of data need to start with this header.
34 */
35struct tcp_log_common_header {
36 uint32_t tlch_version; /* Version is specific to type. */
37 uint32_t tlch_type; /* Type of entry(ies) that follow. */
38 uint64_t tlch_length; /* Total length, including header. */
39} __packed;
40
41#define TCP_LOG_DEV_TYPE_BBR 1 /* black box recorder */
42
43#ifdef _KERNEL
44/*
45 * This is a queue entry. All queue entries need to start with this structure
46 * so the common code can cast them to this structure; however, other modules
47 * are free to include additional data after this structure.
48 *
49 * The elements are explained here:
50 * tldq_queue: used by the common code to maintain this entry's position in the
51 * queue.
52 * tldq_buf: should be NULL, or a pointer to a chunk of data. The data must be
53 * as long as the common header indicates.
54 * tldq_xform: If tldq_buf is NULL, the code will call this to create the
55 * the tldq_buf object. The function should *not* directly modify tldq_buf,
56 * but should return the buffer (which must meet the restrictions
57 * indicated for tldq_buf).
58 * tldq_dtor: This function is called to free the queue entry. If tldq_buf is
59 * not NULL, the dtor function must free that, too.
60 * tldq_refcnt: used by the common code to indicate how many readers still need
61 * this data.
62 */
63struct tcp_log_dev_queue {
64 STAILQ_ENTRY(tcp_log_dev_queue) tldq_queue;
65 struct tcp_log_common_header *tldq_buf;
66 struct tcp_log_common_header *(*tldq_xform)(struct tcp_log_dev_queue *entry);
67 void (*tldq_dtor)(struct tcp_log_dev_queue *entry);
68 volatile u_int tldq_refcnt;
69};
70
71STAILQ_HEAD(log_queueh, tcp_log_dev_queue);
72
73struct tcp_log_dev_info {
74 STAILQ_ENTRY(tcp_log_dev_info) tldi_list;
75 struct tcp_log_dev_queue *tldi_head;
76 struct tcp_log_common_header *tldi_cur;
77 off_t tldi_off;
78};
79STAILQ_HEAD(log_infoh, tcp_log_dev_info);
80
81#ifdef TCP_BLACKBOX
82MALLOC_DECLARE(M_TCPLOGDEV);
83int tcp_log_dev_add_log(struct tcp_log_dev_queue *entry);
84#endif /* TCP_BLACKBOX */
85#endif /* _KERNEL */
86#endif /* !__tcp_log_dev_h__ */