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