random: remove cacheline alignment for locks
[linux-2.6] / drivers / char / drm / drm_scatter.c
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
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
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
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
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
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 }