drm_scatter.c revision 1.3.4.2
1 1.3.4.2 tls /* $NetBSD: drm_scatter.c,v 1.3.4.2 2014/08/20 00:04:20 tls Exp $ */ 2 1.3.4.2 tls 3 1.3.4.2 tls /*- 4 1.3.4.2 tls * Copyright (c) 2013 The NetBSD Foundation, Inc. 5 1.3.4.2 tls * All rights reserved. 6 1.3.4.2 tls * 7 1.3.4.2 tls * This code is derived from software contributed to The NetBSD Foundation 8 1.3.4.2 tls * by Taylor R. Campbell. 9 1.3.4.2 tls * 10 1.3.4.2 tls * Redistribution and use in source and binary forms, with or without 11 1.3.4.2 tls * modification, are permitted provided that the following conditions 12 1.3.4.2 tls * are met: 13 1.3.4.2 tls * 1. Redistributions of source code must retain the above copyright 14 1.3.4.2 tls * notice, this list of conditions and the following disclaimer. 15 1.3.4.2 tls * 2. Redistributions in binary form must reproduce the above copyright 16 1.3.4.2 tls * notice, this list of conditions and the following disclaimer in the 17 1.3.4.2 tls * documentation and/or other materials provided with the distribution. 18 1.3.4.2 tls * 19 1.3.4.2 tls * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 1.3.4.2 tls * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 1.3.4.2 tls * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 1.3.4.2 tls * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 1.3.4.2 tls * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 1.3.4.2 tls * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 1.3.4.2 tls * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 1.3.4.2 tls * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 1.3.4.2 tls * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 1.3.4.2 tls * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 1.3.4.2 tls * POSSIBILITY OF SUCH DAMAGE. 30 1.3.4.2 tls */ 31 1.3.4.2 tls 32 1.3.4.2 tls #include <sys/cdefs.h> 33 1.3.4.2 tls __KERNEL_RCSID(0, "$NetBSD: drm_scatter.c,v 1.3.4.2 2014/08/20 00:04:20 tls Exp $"); 34 1.3.4.2 tls 35 1.3.4.2 tls #include <sys/types.h> 36 1.3.4.2 tls #include <sys/bus.h> 37 1.3.4.2 tls #include <sys/errno.h> 38 1.3.4.2 tls #include <sys/systm.h> 39 1.3.4.2 tls 40 1.3.4.2 tls #include <linux/slab.h> 41 1.3.4.2 tls 42 1.3.4.2 tls #include <drm/drmP.h> 43 1.3.4.2 tls 44 1.3.4.2 tls static int drm_sg_alloc_mem(struct drm_device *, size_t, 45 1.3.4.2 tls struct drm_sg_mem **); 46 1.3.4.2 tls static void drm_sg_free_mem(struct drm_device *, struct drm_sg_mem *); 47 1.3.4.2 tls 48 1.3.4.2 tls int 49 1.3.4.2 tls drm_sg_alloc(struct drm_device *dev, void *data, 50 1.3.4.2 tls struct drm_file *file __unused) 51 1.3.4.2 tls { 52 1.3.4.2 tls struct drm_scatter_gather *const request = data; 53 1.3.4.2 tls struct drm_sg_mem *sg; 54 1.3.4.2 tls int error; 55 1.3.4.2 tls 56 1.3.4.2 tls /* 57 1.3.4.2 tls * XXX Should not hold this mutex during drm_sg_alloc. For 58 1.3.4.2 tls * now, we'll just use non-blocking allocations. 59 1.3.4.2 tls */ 60 1.3.4.2 tls KASSERT(mutex_is_locked(&drm_global_mutex)); 61 1.3.4.2 tls 62 1.3.4.2 tls /* 63 1.3.4.2 tls * Sanity-check the inputs. 64 1.3.4.2 tls */ 65 1.3.4.2 tls if (!drm_core_check_feature(dev, DRIVER_SG)) 66 1.3.4.2 tls return -ENODEV; 67 1.3.4.2 tls if (dev->sg != NULL) 68 1.3.4.2 tls return -EBUSY; 69 1.3.4.2 tls if (request->size > 0xffffffffUL) 70 1.3.4.2 tls return -ENOMEM; 71 1.3.4.2 tls 72 1.3.4.2 tls /* 73 1.3.4.2 tls * Do the allocation. 74 1.3.4.2 tls * 75 1.3.4.2 tls * XXX Would it be safe to drop drm_global_mutex here to avoid 76 1.3.4.2 tls * holding it during allocation? 77 1.3.4.2 tls */ 78 1.3.4.2 tls error = drm_sg_alloc_mem(dev, request->size, &sg); 79 1.3.4.2 tls if (error) 80 1.3.4.2 tls return error; 81 1.3.4.2 tls 82 1.3.4.2 tls /* Set it up to be the device's scatter-gather memory. */ 83 1.3.4.2 tls dev->sg = sg; 84 1.3.4.2 tls 85 1.3.4.2 tls /* Success! */ 86 1.3.4.2 tls request->handle = sg->handle; 87 1.3.4.2 tls return 0; 88 1.3.4.2 tls } 89 1.3.4.2 tls 90 1.3.4.2 tls int 91 1.3.4.2 tls drm_sg_free(struct drm_device *dev, void *data, struct drm_file *file) 92 1.3.4.2 tls { 93 1.3.4.2 tls struct drm_scatter_gather *const request = data; 94 1.3.4.2 tls struct drm_sg_mem *sg; 95 1.3.4.2 tls 96 1.3.4.2 tls KASSERT(mutex_is_locked(&drm_global_mutex)); 97 1.3.4.2 tls 98 1.3.4.2 tls /* 99 1.3.4.2 tls * Sanity-check the inputs. 100 1.3.4.2 tls */ 101 1.3.4.2 tls if (!drm_core_check_feature(dev, DRIVER_SG)) 102 1.3.4.2 tls return -ENODEV; 103 1.3.4.2 tls 104 1.3.4.2 tls sg = dev->sg; 105 1.3.4.2 tls if (sg == NULL) 106 1.3.4.2 tls return -ENXIO; 107 1.3.4.2 tls if (sg->handle != request->handle) 108 1.3.4.2 tls return -EINVAL; 109 1.3.4.2 tls 110 1.3.4.2 tls /* Remove dev->sg. */ 111 1.3.4.2 tls dev->sg = NULL; 112 1.3.4.2 tls 113 1.3.4.2 tls /* Free it. */ 114 1.3.4.2 tls drm_sg_free_mem(dev, sg); 115 1.3.4.2 tls 116 1.3.4.2 tls /* Success! */ 117 1.3.4.2 tls return 0; 118 1.3.4.2 tls } 119 1.3.4.2 tls 120 1.3.4.2 tls void 121 1.3.4.2 tls drm_legacy_sg_cleanup(struct drm_device *dev) 122 1.3.4.2 tls { 123 1.3.4.2 tls 124 1.3.4.2 tls if (!drm_core_check_feature(dev, DRIVER_SG)) 125 1.3.4.2 tls return; 126 1.3.4.2 tls if (dev->sg == NULL) 127 1.3.4.2 tls return; 128 1.3.4.2 tls if (drm_core_check_feature(dev, DRIVER_MODESET)) 129 1.3.4.2 tls return; 130 1.3.4.2 tls 131 1.3.4.2 tls drm_sg_free_mem(dev, dev->sg); 132 1.3.4.2 tls } 133 1.3.4.2 tls 134 1.3.4.2 tls static int 135 1.3.4.2 tls drm_sg_alloc_mem(struct drm_device *dev, size_t size, struct drm_sg_mem **sgp) 136 1.3.4.2 tls { 137 1.3.4.2 tls int nsegs; 138 1.3.4.2 tls int error; 139 1.3.4.2 tls 140 1.3.4.2 tls KASSERT(drm_core_check_feature(dev, DRIVER_SG)); 141 1.3.4.2 tls 142 1.3.4.2 tls KASSERT(size <= (size_t)0xffffffffUL); /* XXX 32-bit sizes only? */ 143 1.3.4.2 tls const size_t nbytes = PAGE_ALIGN(size); 144 1.3.4.2 tls const size_t npages = nbytes >> PAGE_SHIFT; 145 1.3.4.2 tls KASSERT(npages <= (size_t)INT_MAX); 146 1.3.4.2 tls 147 1.3.4.2 tls /* 148 1.3.4.2 tls * Allocate a drm_sg_mem record. 149 1.3.4.2 tls */ 150 1.3.4.2 tls struct drm_sg_mem *const sg = 151 1.3.4.2 tls kmem_zalloc(offsetof(struct drm_sg_mem, sg_segs[npages]), 152 1.3.4.2 tls KM_NOSLEEP); 153 1.3.4.2 tls if (sg == NULL) 154 1.3.4.2 tls return -ENOMEM; 155 1.3.4.2 tls sg->sg_tag = dev->dmat; 156 1.3.4.2 tls sg->sg_nsegs_max = (unsigned int)npages; 157 1.3.4.2 tls 158 1.3.4.2 tls /* 159 1.3.4.2 tls * Allocate the requested amount of DMA-safe memory. 160 1.3.4.2 tls */ 161 1.3.4.2 tls KASSERT(sg->sg_nsegs_max <= (unsigned int)INT_MAX); 162 1.3.4.2 tls /* XXX errno NetBSD->Linux */ 163 1.3.4.2 tls error = -bus_dmamem_alloc(sg->sg_tag, nbytes, PAGE_SIZE, 0, 164 1.3.4.2 tls sg->sg_segs, (int)sg->sg_nsegs_max, &nsegs, BUS_DMA_NOWAIT); 165 1.3.4.2 tls if (error) 166 1.3.4.2 tls goto fail0; 167 1.3.4.2 tls KASSERT(0 <= nsegs); 168 1.3.4.2 tls sg->sg_nsegs = (unsigned int)nsegs; 169 1.3.4.2 tls 170 1.3.4.2 tls /* 171 1.3.4.2 tls * XXX Old drm passed DRM_BUS_NOWAIT below but BUS_DMA_WAITOK 172 1.3.4.2 tls * above. WTF? 173 1.3.4.2 tls */ 174 1.3.4.2 tls 175 1.3.4.2 tls /* 176 1.3.4.2 tls * Map the DMA-safe memory into kernel virtual address space. 177 1.3.4.2 tls */ 178 1.3.4.2 tls /* XXX errno NetBSD->Linux */ 179 1.3.4.2 tls error = -bus_dmamem_map(sg->sg_tag, sg->sg_segs, nsegs, nbytes, 180 1.3.4.2 tls &sg->virtual, 181 1.3.4.2 tls (BUS_DMA_NOWAIT | BUS_DMA_COHERENT | BUS_DMA_NOCACHE)); 182 1.3.4.2 tls if (error) 183 1.3.4.2 tls goto fail1; 184 1.3.4.2 tls sg->sg_size = nbytes; 185 1.3.4.2 tls 186 1.3.4.2 tls /* 187 1.3.4.2 tls * Create a map for DMA transfers. 188 1.3.4.2 tls */ 189 1.3.4.2 tls /* XXX errno NetBSD->Linux */ 190 1.3.4.2 tls error = -bus_dmamap_create(sg->sg_tag, nbytes, nsegs, nbytes, 0, 191 1.3.4.2 tls BUS_DMA_NOWAIT, &sg->sg_map); 192 1.3.4.2 tls if (error) 193 1.3.4.2 tls goto fail2; 194 1.3.4.2 tls 195 1.3.4.2 tls /* 196 1.3.4.2 tls * Load the kva buffer into the map for DMA transfers. 197 1.3.4.2 tls */ 198 1.3.4.2 tls /* XXX errno NetBSD->Linux */ 199 1.3.4.2 tls error = -bus_dmamap_load(sg->sg_tag, sg->sg_map, sg->virtual, nbytes, 200 1.3.4.2 tls NULL, (BUS_DMA_NOWAIT | BUS_DMA_NOCACHE)); 201 1.3.4.2 tls if (error) 202 1.3.4.2 tls goto fail3; 203 1.3.4.2 tls 204 1.3.4.2 tls /* 205 1.3.4.2 tls * Use the kernel virtual address as the userland handle. 206 1.3.4.2 tls * 207 1.3.4.2 tls * XXX This leaks some information about kernel virtual 208 1.3.4.2 tls * addresses to userland; should we use an idr instead? 209 1.3.4.2 tls */ 210 1.3.4.2 tls sg->handle = (unsigned long)(uintptr_t)sg->virtual; 211 1.3.4.2 tls KASSERT(sg->virtual == (void *)(uintptr_t)sg->handle); 212 1.3.4.2 tls 213 1.3.4.2 tls /* Success! */ 214 1.3.4.2 tls *sgp = sg; 215 1.3.4.2 tls return 0; 216 1.3.4.2 tls 217 1.3.4.2 tls fail3: bus_dmamap_destroy(sg->sg_tag, sg->sg_map); 218 1.3.4.2 tls fail2: bus_dmamem_unmap(sg->sg_tag, sg->virtual, sg->sg_size); 219 1.3.4.2 tls fail1: KASSERT(sg->sg_nsegs <= (unsigned int)INT_MAX); 220 1.3.4.2 tls bus_dmamem_free(sg->sg_tag, sg->sg_segs, (int)sg->sg_nsegs); 221 1.3.4.2 tls fail0: sg->sg_tag = NULL; /* XXX paranoia */ 222 1.3.4.2 tls kmem_free(sg, offsetof(struct drm_sg_mem, sg_segs[sg->sg_nsegs_max])); 223 1.3.4.2 tls return error; 224 1.3.4.2 tls } 225 1.3.4.2 tls 226 1.3.4.2 tls static void 227 1.3.4.2 tls drm_sg_free_mem(struct drm_device *dev, struct drm_sg_mem *sg) 228 1.3.4.2 tls { 229 1.3.4.2 tls 230 1.3.4.2 tls bus_dmamap_unload(sg->sg_tag, sg->sg_map); 231 1.3.4.2 tls bus_dmamap_destroy(sg->sg_tag, sg->sg_map); 232 1.3.4.2 tls bus_dmamem_unmap(sg->sg_tag, sg->virtual, sg->sg_size); 233 1.3.4.2 tls KASSERT(sg->sg_nsegs <= (unsigned int)INT_MAX); 234 1.3.4.2 tls bus_dmamem_free(sg->sg_tag, sg->sg_segs, (int)sg->sg_nsegs); 235 1.3.4.2 tls sg->sg_tag = NULL; /* XXX paranoia */ 236 1.3.4.2 tls kmem_free(sg, offsetof(struct drm_sg_mem, sg_segs[sg->sg_nsegs_max])); 237 1.3.4.2 tls } 238
Indexes created Fri Oct 03 15:10:06 GMT 2025