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 /* 31 * Buffer allocation support routines for bus_dmamem_alloc implementations. 32 */ 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/bus.h> 37 #include <sys/busdma_bufalloc.h> 38 #include <sys/domainset.h> 39 #include <sys/malloc.h> 40 41 #include <vm/vm.h> 42 #include <vm/vm_extern.h> 43 #include <vm/vm_kern.h> 44 #include <vm/uma.h> 45 46 /* 47 * We manage buffer zones up to a page in size. Buffers larger than a page can 48 * be managed by one of the kernel's page-oriented memory allocation routines as 49 * efficiently as what we can do here. Also, a page is the largest size for 50 * which we can g'tee contiguity when using uma, and contiguity is one of the 51 * requirements we have to fulfill. 52 */ 53 #define MIN_ZONE_BUFSIZE 32 54 #define MAX_ZONE_BUFSIZE PAGE_SIZE 55 56 /* 57 * The static array of 12 bufzones is big enough to handle all the zones for the 58 * smallest supported allocation size of 32 through the largest supported page 59 * size of 64K. If you up the biggest page size number, up the array size too. 60 * Basically the size of the array needs to be log2(maxsize)-log2(minsize)+1, 61 * but I don't know of an easy way to express that as a compile-time constant. 62 */ 63 #if PAGE_SIZE > 65536 64 #error Unsupported page size 65 #endif 66 67 struct busdma_bufalloc { 68 bus_size_t min_size; 69 size_t num_zones; 70 struct busdma_bufzone buf_zones[12]; 71 }; 72 73 busdma_bufalloc_t 74 busdma_bufalloc_create(const char *name, bus_size_t minimum_alignment, 75 uma_alloc alloc_func, uma_free free_func, uint32_t zcreate_flags) 76 { 77 struct busdma_bufalloc *ba; 78 struct busdma_bufzone *bz; 79 int i; 80 bus_size_t cursize; 81 82 ba = malloc(sizeof(struct busdma_bufalloc), M_DEVBUF, 83 M_ZERO | M_WAITOK); 84 85 ba->min_size = MAX(MIN_ZONE_BUFSIZE, minimum_alignment); 86 87 /* 88 * Each uma zone is created with an alignment of size-1, meaning that 89 * the alignment is equal to the size (I.E., 64 byte buffers are aligned 90 * to 64 byte boundaries, etc). This allows for a fast efficient test 91 * when deciding whether a pool buffer meets the constraints of a given 92 * tag used for allocation: the buffer is usable if tag->alignment <= 93 * bufzone->size. 94 */ 95 for (i = 0, bz = ba->buf_zones, cursize = ba->min_size; 96 i < nitems(ba->buf_zones) && cursize <= MAX_ZONE_BUFSIZE; 97 ++i, ++bz, cursize <<= 1) { 98 snprintf(bz->name, sizeof(bz->name), "dma %.10s %ju", 99 name, (uintmax_t)cursize); 100 bz->size = cursize; 101 bz->umazone = uma_zcreate(bz->name, bz->size, 102 NULL, NULL, NULL, NULL, bz->size - 1, zcreate_flags); 103 if (bz->umazone == NULL) { 104 busdma_bufalloc_destroy(ba); 105 return (NULL); 106 } 107 if (alloc_func != NULL) 108 uma_zone_set_allocf(bz->umazone, alloc_func); 109 if (free_func != NULL) 110 uma_zone_set_freef(bz->umazone, free_func); 111 ++ba->num_zones; 112 } 113 114 return (ba); 115 } 116 117 void 118 busdma_bufalloc_destroy(busdma_bufalloc_t ba) 119 { 120 struct busdma_bufzone *bz; 121 int i; 122 123 if (ba == NULL) 124 return; 125 126 for (i = 0, bz = ba->buf_zones; i < ba->num_zones; ++i, ++bz) { 127 uma_zdestroy(bz->umazone); 128 } 129 130 free(ba, M_DEVBUF); 131 } 132 133 struct busdma_bufzone * 134 busdma_bufalloc_findzone(busdma_bufalloc_t ba, bus_size_t size) 135 { 136 struct busdma_bufzone *bz; 137 int i; 138 139 if (size > MAX_ZONE_BUFSIZE) 140 return (NULL); 141 142 for (i = 0, bz = ba->buf_zones; i < ba->num_zones; ++i, ++bz) { 143 if (bz->size >= size) 144 return (bz); 145 } 146 147 panic("Didn't find a buffer zone of the right size"); 148 } 149 150 void * 151 busdma_bufalloc_alloc_uncacheable(uma_zone_t zone, vm_size_t size, int domain, 152 uint8_t *pflag, int wait) 153 { 154 155 #ifdef VM_MEMATTR_UNCACHEABLE 156 /* Inform UMA that this allocator uses kernel_arena/object. */ 157 *pflag = UMA_SLAB_KERNEL; 158 159 return (kmem_alloc_attr_domainset(DOMAINSET_FIXED(domain), size, 160 wait, 0, BUS_SPACE_MAXADDR, VM_MEMATTR_UNCACHEABLE)); 161 #else 162 panic("VM_MEMATTR_UNCACHEABLE unavailable"); 163 #endif /* VM_MEMATTR_UNCACHEABLE */ 164 } 165 166 void 167 busdma_bufalloc_free_uncacheable(void *item, vm_size_t size, uint8_t pflag) 168 { 169 170 kmem_free(item, size); 171 } 172