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/malloc.h> 41 42 #include <vm/vm.h> 43 #include <vm/vm_extern.h> 44 #include <vm/vm_kern.h> 45 #include <vm/uma.h> 46 47 /* 48 * We manage buffer zones up to a page in size. Buffers larger than a page can 49 * be managed by one of the kernel's page-oriented memory allocation routines as 50 * efficiently as what we can do here. Also, a page is the largest size for 51 * which we can g'tee contiguity when using uma, and contiguity is one of the 52 * requirements we have to fulfill. 53 */ 54 #define MIN_ZONE_BUFSIZE 32 55 #define MAX_ZONE_BUFSIZE PAGE_SIZE 56 57 /* 58 * The static array of 12 bufzones is big enough to handle all the zones for the 59 * smallest supported allocation size of 32 through the largest supported page 60 * size of 64K. If you up the biggest page size number, up the array size too. 61 * Basically the size of the array needs to be log2(maxsize)-log2(minsize)+1, 62 * but I don't know of an easy way to express that as a compile-time constant. 63 */ 64 #if PAGE_SIZE > 65536 65 #error Unsupported page size 66 #endif 67 68 struct busdma_bufalloc { 69 bus_size_t min_size; 70 size_t num_zones; 71 struct busdma_bufzone buf_zones[12]; 72 }; 73 74 busdma_bufalloc_t 75 busdma_bufalloc_create(const char *name, bus_size_t minimum_alignment, 76 uma_alloc alloc_func, uma_free free_func, u_int32_t zcreate_flags) 77 { 78 struct busdma_bufalloc *ba; 79 struct busdma_bufzone *bz; 80 int i; 81 bus_size_t cursize; 82 83 ba = malloc(sizeof(struct busdma_bufalloc), M_DEVBUF, 84 M_ZERO | M_WAITOK); 85 86 ba->min_size = MAX(MIN_ZONE_BUFSIZE, minimum_alignment); 87 88 /* 89 * Each uma zone is created with an alignment of size-1, meaning that 90 * the alignment is equal to the size (I.E., 64 byte buffers are aligned 91 * to 64 byte boundaries, etc). This allows for a fast efficient test 92 * when deciding whether a pool buffer meets the constraints of a given 93 * tag used for allocation: the buffer is usable if tag->alignment <= 94 * bufzone->size. 95 */ 96 for (i = 0, bz = ba->buf_zones, cursize = ba->min_size; 97 i < nitems(ba->buf_zones) && cursize <= MAX_ZONE_BUFSIZE; 98 ++i, ++bz, cursize <<= 1) { 99 snprintf(bz->name, sizeof(bz->name), "dma %.10s %ju", 100 name, (uintmax_t)cursize); 101 bz->size = cursize; 102 bz->umazone = uma_zcreate(bz->name, bz->size, 103 NULL, NULL, NULL, NULL, bz->size - 1, zcreate_flags); 104 if (bz->umazone == NULL) { 105 busdma_bufalloc_destroy(ba); 106 return (NULL); 107 } 108 if (alloc_func != NULL) 109 uma_zone_set_allocf(bz->umazone, alloc_func); 110 if (free_func != NULL) 111 uma_zone_set_freef(bz->umazone, free_func); 112 ++ba->num_zones; 113 } 114 115 return (ba); 116 } 117 118 void 119 busdma_bufalloc_destroy(busdma_bufalloc_t ba) 120 { 121 struct busdma_bufzone *bz; 122 int i; 123 124 if (ba == NULL) 125 return; 126 127 for (i = 0, bz = ba->buf_zones; i < ba->num_zones; ++i, ++bz) { 128 uma_zdestroy(bz->umazone); 129 } 130 131 free(ba, M_DEVBUF); 132 } 133 134 struct busdma_bufzone * 135 busdma_bufalloc_findzone(busdma_bufalloc_t ba, bus_size_t size) 136 { 137 struct busdma_bufzone *bz; 138 int i; 139 140 if (size > MAX_ZONE_BUFSIZE) 141 return (NULL); 142 143 for (i = 0, bz = ba->buf_zones; i < ba->num_zones; ++i, ++bz) { 144 if (bz->size >= size) 145 return (bz); 146 } 147 148 panic("Didn't find a buffer zone of the right size"); 149 } 150 151 void * 152 busdma_bufalloc_alloc_uncacheable(uma_zone_t zone, vm_size_t size, int domain, 153 uint8_t *pflag, int wait) 154 { 155 #ifdef VM_MEMATTR_UNCACHEABLE 156 157 /* Inform UMA that this allocator uses kernel_arena/object. */ 158 *pflag = UMA_SLAB_KERNEL; 159 160 return ((void *)kmem_alloc_attr_domain(domain, size, wait, 0, 161 BUS_SPACE_MAXADDR, VM_MEMATTR_UNCACHEABLE)); 162 163 #else 164 165 panic("VM_MEMATTR_UNCACHEABLE unavailable"); 166 167 #endif /* VM_MEMATTR_UNCACHEABLE */ 168 } 169 170 void 171 busdma_bufalloc_free_uncacheable(void *item, vm_size_t size, uint8_t pflag) 172 { 173 174 kmem_free(kernel_arena, (vm_offset_t)item, size); 175 } 176 177