xref: /third_party/FreeBSD/sys/dev/usb/usb_mbuf.c (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#include "implementation/global_implementation.h"
29
30/*------------------------------------------------------------------------*
31 *      usb_alloc_mbufs - allocate mbufs to an usbd interface queue
32 *
33 * Returns:
34 *   A pointer that should be passed to "free()" when the buffer(s)
35 *   should be released.
36 *------------------------------------------------------------------------*/
37void   *
38usb_alloc_mbufs(struct malloc_type *type, struct usb_ifqueue *ifq,
39    usb_size_t block_size, uint16_t nblocks)
40{
41	struct usb_mbuf *m_ptr;
42	uint8_t *data_ptr;
43	void *free_ptr = NULL;
44	usb_size_t alloc_size;
45
46	/* align data */
47	block_size += ((-block_size) & (USB_HOST_ALIGN - 1));
48
49	if (nblocks && block_size) {
50		alloc_size = (block_size + sizeof(struct usb_mbuf)) * nblocks;
51
52		free_ptr = zalloc(alloc_size);
53
54		if (free_ptr == NULL) {
55			goto done;
56		}
57		m_ptr = free_ptr;
58		data_ptr = (void *)(m_ptr + nblocks);
59
60		while (nblocks--) {
61
62			m_ptr->cur_data_ptr =
63			    m_ptr->min_data_ptr = data_ptr;
64
65			m_ptr->cur_data_len =
66			    m_ptr->max_data_len = block_size;
67
68			USB_IF_ENQUEUE(ifq, m_ptr);
69
70			m_ptr++;
71			data_ptr += block_size;
72		}
73	}
74done:
75	return (free_ptr);
76}
77