Merge branch 'drm-intel-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ickle...
[pandora-kernel.git] / drivers / gpu / 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 <linux/slab.h>
36 #include "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 = 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 }
187 EXPORT_SYMBOL(drm_sg_alloc);
188
189
190 int 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
199 int 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 }