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