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
drm_vmalloc_dma(unsigned long size)39 static inline void *drm_vmalloc_dma(unsigned long size)
40 {
41 #if defined(__powerpc__) && defined(CONFIG_NOT_COHERENT_CACHE)
42 return __vmalloc(size, GFP_KERNEL, PAGE_KERNEL | _PAGE_NO_CACHE);
43 #else
44 return vmalloc_32(size);
45 #endif
46 }
47
drm_sg_cleanup(struct drm_sg_mem * entry)48 void drm_sg_cleanup(struct drm_sg_mem * entry)
49 {
50 struct page *page;
51 int i;
52
53 for (i = 0; i < entry->pages; i++) {
54 page = entry->pagelist[i];
55 if (page)
56 ClearPageReserved(page);
57 }
58
59 vfree(entry->virtual);
60
61 drm_free(entry->busaddr,
62 entry->pages * sizeof(*entry->busaddr), DRM_MEM_PAGES);
63 drm_free(entry->pagelist,
64 entry->pages * sizeof(*entry->pagelist), DRM_MEM_PAGES);
65 drm_free(entry, sizeof(*entry), DRM_MEM_SGLISTS);
66 }
67
68 #ifdef _LP64
69 # define ScatterHandle(x) (unsigned int)((x >> 32) + (x & ((1L << 32) - 1)))
70 #else
71 # define ScatterHandle(x) (unsigned int)(x)
72 #endif
73
drm_sg_alloc(struct drm_device * dev,struct drm_scatter_gather * request)74 int drm_sg_alloc(struct drm_device *dev, struct drm_scatter_gather * request)
75 {
76 struct drm_sg_mem *entry;
77 unsigned long pages, i, j;
78
79 DRM_DEBUG("\n");
80
81 if (!drm_core_check_feature(dev, DRIVER_SG))
82 return -EINVAL;
83
84 if (dev->sg)
85 return -EINVAL;
86
87 entry = drm_alloc(sizeof(*entry), DRM_MEM_SGLISTS);
88 if (!entry)
89 return -ENOMEM;
90
91 memset(entry, 0, sizeof(*entry));
92 pages = (request->size + PAGE_SIZE - 1) / PAGE_SIZE;
93 DRM_DEBUG("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 = drm_vmalloc_dma(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("handle = %08lx\n", entry->handle);
135 DRM_DEBUG("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 dev->sg = entry;
148
149 #if DEBUG_SCATTER
150 /* Verify that each page points to its virtual address, and vice
151 * versa.
152 */
153 {
154 int error = 0;
155
156 for (i = 0; i < pages; i++) {
157 unsigned long *tmp;
158
159 tmp = page_address(entry->pagelist[i]);
160 for (j = 0;
161 j < PAGE_SIZE / sizeof(unsigned long);
162 j++, tmp++) {
163 *tmp = 0xcafebabe;
164 }
165 tmp = (unsigned long *)((u8 *) entry->virtual +
166 (PAGE_SIZE * i));
167 for (j = 0;
168 j < PAGE_SIZE / sizeof(unsigned long);
169 j++, tmp++) {
170 if (*tmp != 0xcafebabe && error == 0) {
171 error = 1;
172 DRM_ERROR("Scatter allocation error, "
173 "pagelist does not match "
174 "virtual mapping\n");
175 }
176 }
177 tmp = page_address(entry->pagelist[i]);
178 for (j = 0;
179 j < PAGE_SIZE / sizeof(unsigned long);
180 j++, tmp++) {
181 *tmp = 0;
182 }
183 }
184 if (error == 0)
185 DRM_ERROR("Scatter allocation matches pagelist\n");
186 }
187 #endif
188
189 return 0;
190
191 failed:
192 drm_sg_cleanup(entry);
193 return -ENOMEM;
194 }
195 EXPORT_SYMBOL(drm_sg_alloc);
196
197
drm_sg_alloc_ioctl(struct drm_device * dev,void * data,struct drm_file * file_priv)198 int drm_sg_alloc_ioctl(struct drm_device *dev, void *data,
199 struct drm_file *file_priv)
200 {
201 struct drm_scatter_gather *request = data;
202
203 return drm_sg_alloc(dev, request);
204
205 }
206
drm_sg_free(struct drm_device * dev,void * data,struct drm_file * file_priv)207 int drm_sg_free(struct drm_device *dev, void *data,
208 struct drm_file *file_priv)
209 {
210 struct drm_scatter_gather *request = data;
211 struct drm_sg_mem *entry;
212
213 if (!drm_core_check_feature(dev, DRIVER_SG))
214 return -EINVAL;
215
216 entry = dev->sg;
217 dev->sg = NULL;
218
219 if (!entry || entry->handle != request->handle)
220 return -EINVAL;
221
222 DRM_DEBUG("virtual = %p\n", entry->virtual);
223
224 drm_sg_cleanup(entry);
225
226 return 0;
227 }
228