1 /** 2 * \file drm_scatter.c 3 * IOCTLs to manage scatter/gather memory 4 * 5 * \author Gareth Hughes <gareth@valinux.com> 6 */ 7 8 /* 9 * Created: Mon Dec 18 23:20:54 2000 by gareth@valinux.com 10 * 11 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. 12 * All Rights Reserved. 13 * 14 * Permission is hereby granted, free of charge, to any person obtaining a 15 * copy of this software and associated documentation files (the "Software"), 16 * to deal in the Software without restriction, including without limitation 17 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 18 * and/or sell copies of the Software, and to permit persons to whom the 19 * Software is furnished to do so, subject to the following conditions: 20 * 21 * The above copyright notice and this permission notice (including the next 22 * paragraph) shall be included in all copies or substantial portions of the 23 * Software. 24 * 25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 26 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 27 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 28 * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR 29 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 30 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 31 * DEALINGS IN THE SOFTWARE. 32 */ 33 34 #include <linux/vmalloc.h> 35 #include <linux/slab.h> 36 #include <drm/drmP.h> 37 #include "drm_legacy.h" 38 39 #define DEBUG_SCATTER 0 40 41 static inline void *drm_vmalloc_dma(unsigned long size) 42 { 43 #if defined(__powerpc__) && defined(CONFIG_NOT_COHERENT_CACHE) 44 return __vmalloc(size, GFP_KERNEL, PAGE_KERNEL | _PAGE_NO_CACHE); 45 #else 46 return vmalloc_32(size); 47 #endif 48 } 49 50 static void drm_sg_cleanup(struct drm_sg_mem * entry) 51 { 52 struct page *page; 53 int i; 54 55 for (i = 0; i < entry->pages; i++) { 56 page = entry->pagelist[i]; 57 if (page) 58 ClearPageReserved(page); 59 } 60 61 vfree(entry->virtual); 62 63 kfree(entry->busaddr); 64 kfree(entry->pagelist); 65 kfree(entry); 66 } 67 68 void drm_legacy_sg_cleanup(struct drm_device *dev) 69 { 70 if (drm_core_check_feature(dev, DRIVER_SG) && dev->sg && 71 !drm_core_check_feature(dev, DRIVER_MODESET)) { 72 drm_sg_cleanup(dev->sg); 73 dev->sg = NULL; 74 } 75 } 76 #ifdef _LP64 77 # define ScatterHandle(x) (unsigned int)((x >> 32) + (x & ((1L << 32) - 1))) 78 #else 79 # define ScatterHandle(x) (unsigned int)(x) 80 #endif 81 82 int drm_legacy_sg_alloc(struct drm_device *dev, void *data, 83 struct drm_file *file_priv) 84 { 85 struct drm_scatter_gather *request = data; 86 struct drm_sg_mem *entry; 87 unsigned long pages, i, j; 88 89 DRM_DEBUG("\n"); 90 91 if (drm_core_check_feature(dev, DRIVER_MODESET)) 92 return -EINVAL; 93 94 if (!drm_core_check_feature(dev, DRIVER_SG)) 95 return -EINVAL; 96 97 if (dev->sg) 98 return -EINVAL; 99 100 entry = kzalloc(sizeof(*entry), GFP_KERNEL); 101 if (!entry) 102 return -ENOMEM; 103 104 pages = (request->size + PAGE_SIZE - 1) / PAGE_SIZE; 105 DRM_DEBUG("size=%ld pages=%ld\n", request->size, pages); 106 107 entry->pages = pages; 108 entry->pagelist = kcalloc(pages, sizeof(*entry->pagelist), GFP_KERNEL); 109 if (!entry->pagelist) { 110 kfree(entry); 111 return -ENOMEM; 112 } 113 114 entry->busaddr = kcalloc(pages, sizeof(*entry->busaddr), GFP_KERNEL); 115 if (!entry->busaddr) { 116 kfree(entry->pagelist); 117 kfree(entry); 118 return -ENOMEM; 119 } 120 121 entry->virtual = drm_vmalloc_dma(pages << PAGE_SHIFT); 122 if (!entry->virtual) { 123 kfree(entry->busaddr); 124 kfree(entry->pagelist); 125 kfree(entry); 126 return -ENOMEM; 127 } 128 129 /* This also forces the mapping of COW pages, so our page list 130 * will be valid. Please don't remove it... 131 */ 132 memset(entry->virtual, 0, pages << PAGE_SHIFT); 133 134 entry->handle = ScatterHandle((unsigned long)entry->virtual); 135 136 DRM_DEBUG("handle = %08lx\n", entry->handle); 137 DRM_DEBUG("virtual = %p\n", entry->virtual); 138 139 for (i = (unsigned long)entry->virtual, j = 0; j < pages; 140 i += PAGE_SIZE, j++) { 141 entry->pagelist[j] = vmalloc_to_page((void *)i); 142 if (!entry->pagelist[j]) 143 goto failed; 144 SetPageReserved(entry->pagelist[j]); 145 } 146 147 request->handle = entry->handle; 148 149 dev->sg = entry; 150 151 #if DEBUG_SCATTER 152 /* Verify that each page points to its virtual address, and vice 153 * versa. 154 */ 155 { 156 int error = 0; 157 158 for (i = 0; i < pages; i++) { 159 unsigned long *tmp; 160 161 tmp = page_address(entry->pagelist[i]); 162 for (j = 0; 163 j < PAGE_SIZE / sizeof(unsigned long); 164 j++, tmp++) { 165 *tmp = 0xcafebabe; 166 } 167 tmp = (unsigned long *)((u8 *) entry->virtual + 168 (PAGE_SIZE * i)); 169 for (j = 0; 170 j < PAGE_SIZE / sizeof(unsigned long); 171 j++, tmp++) { 172 if (*tmp != 0xcafebabe && error == 0) { 173 error = 1; 174 DRM_ERROR("Scatter allocation error, " 175 "pagelist does not match " 176 "virtual mapping\n"); 177 } 178 } 179 tmp = page_address(entry->pagelist[i]); 180 for (j = 0; 181 j < PAGE_SIZE / sizeof(unsigned long); 182 j++, tmp++) { 183 *tmp = 0; 184 } 185 } 186 if (error == 0) 187 DRM_ERROR("Scatter allocation matches pagelist\n"); 188 } 189 #endif 190 191 return 0; 192 193 failed: 194 drm_sg_cleanup(entry); 195 return -ENOMEM; 196 } 197 198 int drm_legacy_sg_free(struct drm_device *dev, void *data, 199 struct drm_file *file_priv) 200 { 201 struct drm_scatter_gather *request = data; 202 struct drm_sg_mem *entry; 203 204 if (drm_core_check_feature(dev, DRIVER_MODESET)) 205 return -EINVAL; 206 207 if (!drm_core_check_feature(dev, DRIVER_SG)) 208 return -EINVAL; 209 210 entry = dev->sg; 211 dev->sg = NULL; 212 213 if (!entry || entry->handle != request->handle) 214 return -EINVAL; 215 216 DRM_DEBUG("virtual = %p\n", entry->virtual); 217 218 drm_sg_cleanup(entry); 219 220 return 0; 221 } 222