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/mm.h> 35 #include <linux/slab.h> 36 #include <linux/vmalloc.h> 37 38 #include <drm/drm.h> 39 #include <drm/drm_drv.h> 40 #include <drm/drm_print.h> 41 42 #include "drm_legacy.h" 43 44 #define DEBUG_SCATTER 0 45 46 static inline void *drm_vmalloc_dma(unsigned long size) 47 { 48 #if defined(__powerpc__) && defined(CONFIG_NOT_COHERENT_CACHE) 49 return __vmalloc(size, GFP_KERNEL, pgprot_noncached_wc(PAGE_KERNEL)); 50 #else 51 return vmalloc_32(size); 52 #endif 53 } 54 55 static void drm_sg_cleanup(struct drm_sg_mem * entry) 56 { 57 struct page *page; 58 int i; 59 60 for (i = 0; i < entry->pages; i++) { 61 page = entry->pagelist[i]; 62 if (page) 63 ClearPageReserved(page); 64 } 65 66 vfree(entry->virtual); 67 68 kfree(entry->busaddr); 69 kfree(entry->pagelist); 70 kfree(entry); 71 } 72 73 void drm_legacy_sg_cleanup(struct drm_device *dev) 74 { 75 if (drm_core_check_feature(dev, DRIVER_SG) && dev->sg && 76 drm_core_check_feature(dev, DRIVER_LEGACY)) { 77 drm_sg_cleanup(dev->sg); 78 dev->sg = NULL; 79 } 80 } 81 #ifdef _LP64 82 # define ScatterHandle(x) (unsigned int)((x >> 32) + (x & ((1L << 32) - 1))) 83 #else 84 # define ScatterHandle(x) (unsigned int)(x) 85 #endif 86 87 int drm_legacy_sg_alloc(struct drm_device *dev, void *data, 88 struct drm_file *file_priv) 89 { 90 struct drm_scatter_gather *request = data; 91 struct drm_sg_mem *entry; 92 unsigned long pages, i, j; 93 94 DRM_DEBUG("\n"); 95 96 if (!drm_core_check_feature(dev, DRIVER_LEGACY)) 97 return -EOPNOTSUPP; 98 99 if (!drm_core_check_feature(dev, DRIVER_SG)) 100 return -EOPNOTSUPP; 101 102 if (request->size > SIZE_MAX - PAGE_SIZE) 103 return -EINVAL; 104 105 if (dev->sg) 106 return -EINVAL; 107 108 entry = kzalloc(sizeof(*entry), GFP_KERNEL); 109 if (!entry) 110 return -ENOMEM; 111 112 pages = (request->size + PAGE_SIZE - 1) / PAGE_SIZE; 113 DRM_DEBUG("size=%ld pages=%ld\n", request->size, pages); 114 115 entry->pages = pages; 116 entry->pagelist = kcalloc(pages, sizeof(*entry->pagelist), GFP_KERNEL); 117 if (!entry->pagelist) { 118 kfree(entry); 119 return -ENOMEM; 120 } 121 122 entry->busaddr = kcalloc(pages, sizeof(*entry->busaddr), GFP_KERNEL); 123 if (!entry->busaddr) { 124 kfree(entry->pagelist); 125 kfree(entry); 126 return -ENOMEM; 127 } 128 129 entry->virtual = drm_vmalloc_dma(pages << PAGE_SHIFT); 130 if (!entry->virtual) { 131 kfree(entry->busaddr); 132 kfree(entry->pagelist); 133 kfree(entry); 134 return -ENOMEM; 135 } 136 137 /* This also forces the mapping of COW pages, so our page list 138 * will be valid. Please don't remove it... 139 */ 140 memset(entry->virtual, 0, pages << PAGE_SHIFT); 141 142 entry->handle = ScatterHandle((unsigned long)entry->virtual); 143 144 DRM_DEBUG("handle = %08lx\n", entry->handle); 145 DRM_DEBUG("virtual = %p\n", entry->virtual); 146 147 for (i = (unsigned long)entry->virtual, j = 0; j < pages; 148 i += PAGE_SIZE, j++) { 149 entry->pagelist[j] = vmalloc_to_page((void *)i); 150 if (!entry->pagelist[j]) 151 goto failed; 152 SetPageReserved(entry->pagelist[j]); 153 } 154 155 request->handle = entry->handle; 156 157 dev->sg = entry; 158 159 #if DEBUG_SCATTER 160 /* Verify that each page points to its virtual address, and vice 161 * versa. 162 */ 163 { 164 int error = 0; 165 166 for (i = 0; i < pages; i++) { 167 unsigned long *tmp; 168 169 tmp = page_address(entry->pagelist[i]); 170 for (j = 0; 171 j < PAGE_SIZE / sizeof(unsigned long); 172 j++, tmp++) { 173 *tmp = 0xcafebabe; 174 } 175 tmp = (unsigned long *)((u8 *) entry->virtual + 176 (PAGE_SIZE * i)); 177 for (j = 0; 178 j < PAGE_SIZE / sizeof(unsigned long); 179 j++, tmp++) { 180 if (*tmp != 0xcafebabe && error == 0) { 181 error = 1; 182 DRM_ERROR("Scatter allocation error, " 183 "pagelist does not match " 184 "virtual mapping\n"); 185 } 186 } 187 tmp = page_address(entry->pagelist[i]); 188 for (j = 0; 189 j < PAGE_SIZE / sizeof(unsigned long); 190 j++, tmp++) { 191 *tmp = 0; 192 } 193 } 194 if (error == 0) 195 DRM_ERROR("Scatter allocation matches pagelist\n"); 196 } 197 #endif 198 199 return 0; 200 201 failed: 202 drm_sg_cleanup(entry); 203 return -ENOMEM; 204 } 205 206 int drm_legacy_sg_free(struct drm_device *dev, void *data, 207 struct drm_file *file_priv) 208 { 209 struct drm_scatter_gather *request = data; 210 struct drm_sg_mem *entry; 211 212 if (!drm_core_check_feature(dev, DRIVER_LEGACY)) 213 return -EOPNOTSUPP; 214 215 if (!drm_core_check_feature(dev, DRIVER_SG)) 216 return -EOPNOTSUPP; 217 218 entry = dev->sg; 219 dev->sg = NULL; 220 221 if (!entry || entry->handle != request->handle) 222 return -EINVAL; 223 224 DRM_DEBUG("virtual = %p\n", entry->virtual); 225 226 drm_sg_cleanup(entry); 227 228 return 0; 229 } 230