drivers: use kzalloc/kcalloc instead of 'kmalloc+memset', where possible
[linux-2.6.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 = 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 }