1/* $FreeBSD$ */
2/*-
3 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 *
5 * Copyright (c) 2008 Hans Petter Selasky. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#ifndef _USB_MBUF_H_
30#define	_USB_MBUF_H_
31
32/*
33 * The following structure defines a minimum re-implementation of the
34 * mbuf system in the kernel.
35 */
36struct usb_mbuf {
37	uint8_t *cur_data_ptr;
38	uint8_t *min_data_ptr;
39	struct usb_mbuf *usb_nextpkt;
40	struct usb_mbuf *usb_next;
41
42	usb_size_t cur_data_len;
43	usb_size_t max_data_len;
44	uint8_t last_packet:1;
45	uint8_t unused:7;
46};
47
48#define	USB_IF_ENQUEUE(ifq, m) do {		\
49    (m)->usb_nextpkt = NULL;			\
50    if ((ifq)->ifq_tail == NULL)		\
51        (ifq)->ifq_head = (m);			\
52    else					\
53        (ifq)->ifq_tail->usb_nextpkt = (m);	\
54    (ifq)->ifq_tail = (m);			\
55    (ifq)->ifq_len++;				\
56  } while (0)
57
58#define	USB_IF_DEQUEUE(ifq, m) do {				\
59    (m) = (ifq)->ifq_head;					\
60    if (m) {							\
61        if (((ifq)->ifq_head = (m)->usb_nextpkt) == NULL) {	\
62	     (ifq)->ifq_tail = NULL;				\
63	}							\
64	(m)->usb_nextpkt = NULL;				\
65	(ifq)->ifq_len--;					\
66    }								\
67  } while (0)
68
69#define	USB_IF_PREPEND(ifq, m) do {		\
70      (m)->usb_nextpkt = (ifq)->ifq_head;	\
71      if ((ifq)->ifq_tail == NULL) {		\
72	  (ifq)->ifq_tail = (m);		\
73      }						\
74      (ifq)->ifq_head = (m);			\
75      (ifq)->ifq_len++;				\
76  } while (0)
77
78#define	USB_IF_QFULL(ifq)   ((ifq)->ifq_len >= (ifq)->ifq_maxlen)
79#define	USB_IF_QLEN(ifq)    ((ifq)->ifq_len)
80#define	USB_IF_POLL(ifq, m) ((m) = (ifq)->ifq_head)
81
82#define	USB_MBUF_RESET(m) do {			\
83    (m)->cur_data_ptr = (m)->min_data_ptr;	\
84    (m)->cur_data_len = (m)->max_data_len;	\
85    (m)->last_packet = 0;			\
86  } while (0)
87
88/* prototypes */
89void   *usb_alloc_mbufs(struct malloc_type *type, struct usb_ifqueue *ifq,
90	    usb_size_t block_size, uint16_t nblocks);
91
92#endif					/* _USB_MBUF_H_ */
93