freebsd-dev/sys/dev/tcp_log/tcp_log_dev.h
Jonathan T. Looney e24e568336 Make the TCP blackbox code committed in r331347 be an optional feature
controlled by the TCP_BLACKBOX option.

Enable this as part of amd64 GENERIC. For now, leave it disabled on
other platforms.

Sponsored by:	Netflix, Inc.
2018-03-24 12:48:10 +00:00

90 lines
3.5 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2016
* Netflix Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef __tcp_log_dev_h__
#define __tcp_log_dev_h__
/*
* This is the common header for data streamed from the log device. All
* blocks of data need to start with this header.
*/
struct tcp_log_common_header {
uint32_t tlch_version; /* Version is specific to type. */
uint32_t tlch_type; /* Type of entry(ies) that follow. */
uint64_t tlch_length; /* Total length, including header. */
} __packed;
#define TCP_LOG_DEV_TYPE_BBR 1 /* black box recorder */
#ifdef _KERNEL
/*
* This is a queue entry. All queue entries need to start with this structure
* so the common code can cast them to this structure; however, other modules
* are free to include additional data after this structure.
*
* The elements are explained here:
* tldq_queue: used by the common code to maintain this entry's position in the
* queue.
* tldq_buf: should be NULL, or a pointer to a chunk of data. The data must be
* as long as the common header indicates.
* tldq_xform: If tldq_buf is NULL, the code will call this to create the
* the tldq_buf object. The function should *not* directly modify tldq_buf,
* but should return the buffer (which must meet the restrictions
* indicated for tldq_buf).
* tldq_dtor: This function is called to free the queue entry. If tldq_buf is
* not NULL, the dtor function must free that, too.
* tldq_refcnt: used by the common code to indicate how many readers still need
* this data.
*/
struct tcp_log_dev_queue {
STAILQ_ENTRY(tcp_log_dev_queue) tldq_queue;
struct tcp_log_common_header *tldq_buf;
struct tcp_log_common_header *(*tldq_xform)(struct tcp_log_dev_queue *entry);
void (*tldq_dtor)(struct tcp_log_dev_queue *entry);
volatile u_int tldq_refcnt;
};
STAILQ_HEAD(log_queueh, tcp_log_dev_queue);
struct tcp_log_dev_info {
STAILQ_ENTRY(tcp_log_dev_info) tldi_list;
struct tcp_log_dev_queue *tldi_head;
struct tcp_log_common_header *tldi_cur;
off_t tldi_off;
};
STAILQ_HEAD(log_infoh, tcp_log_dev_info);
#ifdef TCP_BLACKBOX
MALLOC_DECLARE(M_TCPLOGDEV);
int tcp_log_dev_add_log(struct tcp_log_dev_queue *entry);
#endif /* TCP_BLACKBOX */
#endif /* _KERNEL */
#endif /* !__tcp_log_dev_h__ */