xref: /third_party/FreeBSD/sys/dev/usb/usb_mbuf.h (revision f9f848fa)
1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2008 Hans Petter Selasky. All rights reserved.
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 _USB_MBUF_H_
29#define	_USB_MBUF_H_
30
31/*
32 * The following structure defines a minimum re-implementation of the
33 * mbuf system in the kernel.
34 */
35struct usb_mbuf {
36	uint8_t *cur_data_ptr;
37	uint8_t *min_data_ptr;
38	struct usb_mbuf *usb_nextpkt;
39	struct usb_mbuf *usb_next;
40
41	usb_size_t cur_data_len;
42	usb_size_t max_data_len;
43	uint8_t last_packet:1;
44	uint8_t unused:7;
45};
46
47#define	USB_IF_ENQUEUE(ifq, m) do {		\
48    (m)->usb_nextpkt = NULL;			\
49    if ((ifq)->ifq_tail == NULL)		\
50        (ifq)->ifq_head = (m);			\
51    else					\
52        (ifq)->ifq_tail->usb_nextpkt = (m);	\
53    (ifq)->ifq_tail = (m);			\
54    (ifq)->ifq_len++;				\
55  } while (0)
56
57#define	USB_IF_DEQUEUE(ifq, m) do {				\
58    (m) = (ifq)->ifq_head;					\
59    if (m) {							\
60        if (((ifq)->ifq_head = (m)->usb_nextpkt) == NULL) {	\
61	     (ifq)->ifq_tail = NULL;				\
62	}							\
63	(m)->usb_nextpkt = NULL;				\
64	(ifq)->ifq_len--;					\
65    }								\
66  } while (0)
67
68#define	USB_IF_PREPEND(ifq, m) do {		\
69      (m)->usb_nextpkt = (ifq)->ifq_head;	\
70      if ((ifq)->ifq_tail == NULL) {		\
71	  (ifq)->ifq_tail = (m);		\
72      }						\
73      (ifq)->ifq_head = (m);			\
74      (ifq)->ifq_len++;				\
75  } while (0)
76
77#define	USB_IF_QFULL(ifq)   ((ifq)->ifq_len >= (ifq)->ifq_maxlen)
78#define	USB_IF_QLEN(ifq)    ((ifq)->ifq_len)
79#define	USB_IF_POLL(ifq, m) ((m) = (ifq)->ifq_head)
80
81#define	USB_MBUF_RESET(m) do {			\
82    (m)->cur_data_ptr = (m)->min_data_ptr;	\
83    (m)->cur_data_len = (m)->max_data_len;	\
84    (m)->last_packet = 0;			\
85  } while (0)
86
87/* prototypes */
88void   *usb_alloc_mbufs(struct malloc_type *type, struct usb_ifqueue *ifq,
89	    usb_size_t block_size, uint16_t nblocks);
90
91#endif					/* _USB_MBUF_H_ */
92