1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2012 Ian Lepore
5 * 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#include <sys/cdefs.h>
30__FBSDID("$FreeBSD$");
31
32/*
33 * Buffer allocation support routines for bus_dmamem_alloc implementations.
34 */
35
36#include <sys/param.h>
37#include <sys/systm.h>
38#include <sys/bus.h>
39#include <sys/busdma_bufalloc.h>
40#include <sys/domainset.h>
41#include <sys/malloc.h>
42
43#include <vm/vm.h>
44#include <vm/vm_extern.h>
45#include <vm/vm_kern.h>
46#include <vm/uma.h>
47
48/*
49 * We manage buffer zones up to a page in size.  Buffers larger than a page can
50 * be managed by one of the kernel's page-oriented memory allocation routines as
51 * efficiently as what we can do here.  Also, a page is the largest size for
52 * which we can g'tee contiguity when using uma, and contiguity is one of the
53 * requirements we have to fulfill.
54 */
55#define	MIN_ZONE_BUFSIZE	32
56#define	MAX_ZONE_BUFSIZE	PAGE_SIZE
57
58/*
59 * The static array of 12 bufzones is big enough to handle all the zones for the
60 * smallest supported allocation size of 32 through the largest supported page
61 * size of 64K.  If you up the biggest page size number, up the array size too.
62 * Basically the size of the array needs to be log2(maxsize)-log2(minsize)+1,
63 * but I don't know of an easy way to express that as a compile-time constant.
64 */
65#if PAGE_SIZE > 65536
66#error Unsupported page size
67#endif
68
69struct busdma_bufalloc {
70	bus_size_t		min_size;
71	size_t			num_zones;
72	struct busdma_bufzone	buf_zones[12];
73};
74
75busdma_bufalloc_t
76busdma_bufalloc_create(const char *name, bus_size_t minimum_alignment,
77    uma_alloc alloc_func, uma_free free_func, u_int32_t zcreate_flags)
78{
79	struct busdma_bufalloc *ba;
80	struct busdma_bufzone *bz;
81	int i;
82	bus_size_t cursize;
83
84	ba = malloc(sizeof(struct busdma_bufalloc), M_DEVBUF,
85	    M_ZERO | M_WAITOK);
86
87	ba->min_size = MAX(MIN_ZONE_BUFSIZE, minimum_alignment);
88
89	/*
90	 * Each uma zone is created with an alignment of size-1, meaning that
91	 * the alignment is equal to the size (I.E., 64 byte buffers are aligned
92	 * to 64 byte boundaries, etc).  This allows for a fast efficient test
93	 * when deciding whether a pool buffer meets the constraints of a given
94	 * tag used for allocation: the buffer is usable if tag->alignment <=
95	 * bufzone->size.
96	 */
97	for (i = 0, bz = ba->buf_zones, cursize = ba->min_size;
98	    i < nitems(ba->buf_zones) && cursize <= MAX_ZONE_BUFSIZE;
99	    ++i, ++bz, cursize <<= 1) {
100		snprintf(bz->name, sizeof(bz->name), "dma %.10s %ju",
101		    name, (uintmax_t)cursize);
102		bz->size = cursize;
103		bz->umazone = uma_zcreate(bz->name, bz->size,
104		    NULL, NULL, NULL, NULL, bz->size - 1, zcreate_flags);
105		if (bz->umazone == NULL) {
106			busdma_bufalloc_destroy(ba);
107			return (NULL);
108		}
109		if (alloc_func != NULL)
110			uma_zone_set_allocf(bz->umazone, alloc_func);
111		if (free_func != NULL)
112			uma_zone_set_freef(bz->umazone, free_func);
113		++ba->num_zones;
114	}
115
116	return (ba);
117}
118
119void
120busdma_bufalloc_destroy(busdma_bufalloc_t ba)
121{
122	struct busdma_bufzone *bz;
123	int i;
124
125	if (ba == NULL)
126		return;
127
128	for (i = 0, bz = ba->buf_zones; i < ba->num_zones; ++i, ++bz) {
129		uma_zdestroy(bz->umazone);
130	}
131
132	free(ba, M_DEVBUF);
133}
134
135struct busdma_bufzone *
136busdma_bufalloc_findzone(busdma_bufalloc_t ba, bus_size_t size)
137{
138	struct busdma_bufzone *bz;
139	int i;
140
141	if (size > MAX_ZONE_BUFSIZE)
142		return (NULL);
143
144	for (i = 0, bz = ba->buf_zones; i < ba->num_zones; ++i, ++bz) {
145		if (bz->size >= size)
146			return (bz);
147	}
148
149	panic("Didn't find a buffer zone of the right size");
150}
151
152void *
153busdma_bufalloc_alloc_uncacheable(uma_zone_t zone, vm_size_t size, int domain,
154    uint8_t *pflag, int wait)
155{
156
157#ifdef VM_MEMATTR_UNCACHEABLE
158	/* Inform UMA that this allocator uses kernel_arena/object. */
159	*pflag = UMA_SLAB_KERNEL;
160
161	return ((void *)kmem_alloc_attr_domainset(DOMAINSET_FIXED(domain), size,
162	    wait, 0, BUS_SPACE_MAXADDR, VM_MEMATTR_UNCACHEABLE));
163#else
164	panic("VM_MEMATTR_UNCACHEABLE unavailable");
165#endif	/* VM_MEMATTR_UNCACHEABLE */
166}
167
168void
169busdma_bufalloc_free_uncacheable(void *item, vm_size_t size, uint8_t pflag)
170{
171
172	kmem_free((vm_offset_t)item, size);
173}
174