usb_mbuf.c revision 190633 
1/* $FreeBSD: head/sys/dev/usb/usb_mbuf.c 190633 2009-04-01 20:23:47Z piso $ */
2/*-
3 * Copyright (c) 2008 Hans Petter Selasky. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <dev/usb/usb_core.h>
28#include <dev/usb/usb_mbuf.h>
29
30/*------------------------------------------------------------------------*
31 *      usb2_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   *
38usb2_alloc_mbufs(struct malloc_type *type, struct usb2_ifqueue *ifq,
39    usb2_size_t block_size, uint16_t nblocks)
40{
41	struct usb2_mbuf *m_ptr;
42	uint8_t *data_ptr;
43	void *free_ptr = NULL;
44	usb2_size_t alloc_size;
45
46	/* align data */
47	block_size += ((-block_size) & (USB_HOST_ALIGN - 1));
48
49	if (nblocks && block_size) {
50
51		alloc_size = (block_size + sizeof(struct usb2_mbuf)) * nblocks;
52
53		free_ptr = malloc(alloc_size, type, M_WAITOK | M_ZERO);
54
55		if (free_ptr == NULL) {
56			goto done;
57		}
58		m_ptr = free_ptr;
59		data_ptr = (void *)(m_ptr + nblocks);
60
61		while (nblocks--) {
62
63			m_ptr->cur_data_ptr =
64			    m_ptr->min_data_ptr = data_ptr;
65
66			m_ptr->cur_data_len =
67			    m_ptr->max_data_len = block_size;
68
69			USB_IF_ENQUEUE(ifq, m_ptr);
70
71			m_ptr++;
72			data_ptr += block_size;
73		}
74	}
75done:
76	return (free_ptr);
77}
78