| 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 | |
| 38 | #define DEBUG_SCATTER 0 |
| 39 | |
| 40 | static 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 | |
| 49 | void 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 | |
| 73 | int 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 = kzalloc(sizeof(*entry), GFP_KERNEL); |
| 87 | if (!entry) |
| 88 | return -ENOMEM; |
| 89 | |
| 90 | pages = (request->size + PAGE_SIZE - 1) / PAGE_SIZE; |
| 91 | DRM_DEBUG("size=%ld pages=%ld\n", request->size, pages); |
| 92 | |
| 93 | entry->pages = pages; |
| 94 | entry->pagelist = kcalloc(pages, sizeof(*entry->pagelist), GFP_KERNEL); |
| 95 | if (!entry->pagelist) { |
| 96 | kfree(entry); |
| 97 | return -ENOMEM; |
| 98 | } |
| 99 | |
| 100 | entry->busaddr = kcalloc(pages, sizeof(*entry->busaddr), GFP_KERNEL); |
| 101 | if (!entry->busaddr) { |
| 102 | kfree(entry->pagelist); |
| 103 | kfree(entry); |
| 104 | return -ENOMEM; |
| 105 | } |
| 106 | |
| 107 | entry->virtual = drm_vmalloc_dma(pages << PAGE_SHIFT); |
| 108 | if (!entry->virtual) { |
| 109 | kfree(entry->busaddr); |
| 110 | kfree(entry->pagelist); |
| 111 | kfree(entry); |
| 112 | return -ENOMEM; |
| 113 | } |
| 114 | |
| 115 | /* This also forces the mapping of COW pages, so our page list |
| 116 | * will be valid. Please don't remove it... |
| 117 | */ |
| 118 | memset(entry->virtual, 0, pages << PAGE_SHIFT); |
| 119 | |
| 120 | entry->handle = ScatterHandle((unsigned long)entry->virtual); |
| 121 | |
| 122 | DRM_DEBUG("handle = %08lx\n", entry->handle); |
| 123 | DRM_DEBUG("virtual = %p\n", entry->virtual); |
| 124 | |
| 125 | for (i = (unsigned long)entry->virtual, j = 0; j < pages; |
| 126 | i += PAGE_SIZE, j++) { |
| 127 | entry->pagelist[j] = vmalloc_to_page((void *)i); |
| 128 | if (!entry->pagelist[j]) |
| 129 | goto failed; |
| 130 | SetPageReserved(entry->pagelist[j]); |
| 131 | } |
| 132 | |
| 133 | request->handle = entry->handle; |
| 134 | |
| 135 | dev->sg = entry; |
| 136 | |
| 137 | #if DEBUG_SCATTER |
| 138 | /* Verify that each page points to its virtual address, and vice |
| 139 | * versa. |
| 140 | */ |
| 141 | { |
| 142 | int error = 0; |
| 143 | |
| 144 | for (i = 0; i < pages; i++) { |
| 145 | unsigned long *tmp; |
| 146 | |
| 147 | tmp = page_address(entry->pagelist[i]); |
| 148 | for (j = 0; |
| 149 | j < PAGE_SIZE / sizeof(unsigned long); |
| 150 | j++, tmp++) { |
| 151 | *tmp = 0xcafebabe; |
| 152 | } |
| 153 | tmp = (unsigned long *)((u8 *) entry->virtual + |
| 154 | (PAGE_SIZE * i)); |
| 155 | for (j = 0; |
| 156 | j < PAGE_SIZE / sizeof(unsigned long); |
| 157 | j++, tmp++) { |
| 158 | if (*tmp != 0xcafebabe && error == 0) { |
| 159 | error = 1; |
| 160 | DRM_ERROR("Scatter allocation error, " |
| 161 | "pagelist does not match " |
| 162 | "virtual mapping\n"); |
| 163 | } |
| 164 | } |
| 165 | tmp = page_address(entry->pagelist[i]); |
| 166 | for (j = 0; |
| 167 | j < PAGE_SIZE / sizeof(unsigned long); |
| 168 | j++, tmp++) { |
| 169 | *tmp = 0; |
| 170 | } |
| 171 | } |
| 172 | if (error == 0) |
| 173 | DRM_ERROR("Scatter allocation matches pagelist\n"); |
| 174 | } |
| 175 | #endif |
| 176 | |
| 177 | return 0; |
| 178 | |
| 179 | failed: |
| 180 | drm_sg_cleanup(entry); |
| 181 | return -ENOMEM; |
| 182 | } |
| 183 | |
| 184 | int drm_sg_alloc_ioctl(struct drm_device *dev, void *data, |
| 185 | struct drm_file *file_priv) |
| 186 | { |
| 187 | struct drm_scatter_gather *request = data; |
| 188 | |
| 189 | return drm_sg_alloc(dev, request); |
| 190 | |
| 191 | } |
| 192 | |
| 193 | int drm_sg_free(struct drm_device *dev, void *data, |
| 194 | struct drm_file *file_priv) |
| 195 | { |
| 196 | struct drm_scatter_gather *request = data; |
| 197 | struct drm_sg_mem *entry; |
| 198 | |
| 199 | if (!drm_core_check_feature(dev, DRIVER_SG)) |
| 200 | return -EINVAL; |
| 201 | |
| 202 | entry = dev->sg; |
| 203 | dev->sg = NULL; |
| 204 | |
| 205 | if (!entry || entry->handle != request->handle) |
| 206 | return -EINVAL; |
| 207 | |
| 208 | DRM_DEBUG("virtual = %p\n", entry->virtual); |
| 209 | |
| 210 | drm_sg_cleanup(entry); |
| 211 | |
| 212 | return 0; |
| 213 | } |