1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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 69 struct busdma_bufalloc { 70 bus_size_t min_size; 71 size_t num_zones; 72 struct busdma_bufzone buf_zones[12]; 73 }; 74 75 busdma_bufalloc_t 76 busdma_bufalloc_create(const char *name, bus_size_t minimum_alignment, 77 uma_alloc alloc_func, uma_free free_func, uint32_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 } 118 119 void 120 busdma_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 } 134 135 struct busdma_bufzone * 136 busdma_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 } 151 152 void * 153 busdma_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 (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 } 167 168 void 169 busdma_bufalloc_free_uncacheable(void *item, vm_size_t size, uint8_t pflag) 170 { 171 172 kmem_free(item, size); 173 } 174