tcp_log_dev.h (3545B) - Raw
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 */ 35 struct 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 */ 63 struct 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 71 STAILQ_HEAD(log_queueh, tcp_log_dev_queue); 72 73 struct 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 }; 79 STAILQ_HEAD(log_infoh, tcp_log_dev_info); 80 81 #ifdef TCP_BLACKBOX 82 MALLOC_DECLARE(M_TCPLOGDEV); 83 int tcp_log_dev_add_log(struct tcp_log_dev_queue *entry); 84 #endif /* TCP_BLACKBOX */ 85 #endif /* _KERNEL */ 86 #endif /* !__tcp_log_dev_h__ */