Linux 2.6.33-rc6
[cris-mirror.git] / drivers / gpu / drm / drm_scatter.c
blobc7823c863d4f35fb85b0fc5056b19cd08da4b336
1 /**
2 * \file drm_scatter.c
3 * IOCTLs to manage scatter/gather memory
5 * \author Gareth Hughes <gareth@valinux.com>
6 */
8 /*
9 * Created: Mon Dec 18 23:20:54 2000 by gareth@valinux.com
11 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
12 * All Rights Reserved.
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:
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.
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.
34 #include <linux/vmalloc.h>
35 #include "drmP.h"
37 #define DEBUG_SCATTER 0
39 static inline void *drm_vmalloc_dma(unsigned long size)
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
48 void drm_sg_cleanup(struct drm_sg_mem * entry)
50 struct page *page;
51 int i;
53 for (i = 0; i < entry->pages; i++) {
54 page = entry->pagelist[i];
55 if (page)
56 ClearPageReserved(page);
59 vfree(entry->virtual);
61 kfree(entry->busaddr);
62 kfree(entry->pagelist);
63 kfree(entry);
66 #ifdef _LP64
67 # define ScatterHandle(x) (unsigned int)((x >> 32) + (x & ((1L << 32) - 1)))
68 #else
69 # define ScatterHandle(x) (unsigned int)(x)
70 #endif
72 int drm_sg_alloc(struct drm_device *dev, struct drm_scatter_gather * request)
74 struct drm_sg_mem *entry;
75 unsigned long pages, i, j;
77 DRM_DEBUG("\n");
79 if (!drm_core_check_feature(dev, DRIVER_SG))
80 return -EINVAL;
82 if (dev->sg)
83 return -EINVAL;
85 entry = kmalloc(sizeof(*entry), GFP_KERNEL);
86 if (!entry)
87 return -ENOMEM;
89 memset(entry, 0, sizeof(*entry));
90 pages = (request->size + PAGE_SIZE - 1) / PAGE_SIZE;
91 DRM_DEBUG("size=%ld pages=%ld\n", request->size, pages);
93 entry->pages = pages;
94 entry->pagelist = kmalloc(pages * sizeof(*entry->pagelist), GFP_KERNEL);
95 if (!entry->pagelist) {
96 kfree(entry);
97 return -ENOMEM;
100 memset(entry->pagelist, 0, pages * sizeof(*entry->pagelist));
102 entry->busaddr = kmalloc(pages * sizeof(*entry->busaddr), GFP_KERNEL);
103 if (!entry->busaddr) {
104 kfree(entry->pagelist);
105 kfree(entry);
106 return -ENOMEM;
108 memset((void *)entry->busaddr, 0, pages * sizeof(*entry->busaddr));
110 entry->virtual = drm_vmalloc_dma(pages << PAGE_SHIFT);
111 if (!entry->virtual) {
112 kfree(entry->busaddr);
113 kfree(entry->pagelist);
114 kfree(entry);
115 return -ENOMEM;
118 /* This also forces the mapping of COW pages, so our page list
119 * will be valid. Please don't remove it...
121 memset(entry->virtual, 0, pages << PAGE_SHIFT);
123 entry->handle = ScatterHandle((unsigned long)entry->virtual);
125 DRM_DEBUG("handle = %08lx\n", entry->handle);
126 DRM_DEBUG("virtual = %p\n", entry->virtual);
128 for (i = (unsigned long)entry->virtual, j = 0; j < pages;
129 i += PAGE_SIZE, j++) {
130 entry->pagelist[j] = vmalloc_to_page((void *)i);
131 if (!entry->pagelist[j])
132 goto failed;
133 SetPageReserved(entry->pagelist[j]);
136 request->handle = entry->handle;
138 dev->sg = entry;
140 #if DEBUG_SCATTER
141 /* Verify that each page points to its virtual address, and vice
142 * versa.
145 int error = 0;
147 for (i = 0; i < pages; i++) {
148 unsigned long *tmp;
150 tmp = page_address(entry->pagelist[i]);
151 for (j = 0;
152 j < PAGE_SIZE / sizeof(unsigned long);
153 j++, tmp++) {
154 *tmp = 0xcafebabe;
156 tmp = (unsigned long *)((u8 *) entry->virtual +
157 (PAGE_SIZE * i));
158 for (j = 0;
159 j < PAGE_SIZE / sizeof(unsigned long);
160 j++, tmp++) {
161 if (*tmp != 0xcafebabe && error == 0) {
162 error = 1;
163 DRM_ERROR("Scatter allocation error, "
164 "pagelist does not match "
165 "virtual mapping\n");
168 tmp = page_address(entry->pagelist[i]);
169 for (j = 0;
170 j < PAGE_SIZE / sizeof(unsigned long);
171 j++, tmp++) {
172 *tmp = 0;
175 if (error == 0)
176 DRM_ERROR("Scatter allocation matches pagelist\n");
178 #endif
180 return 0;
182 failed:
183 drm_sg_cleanup(entry);
184 return -ENOMEM;
186 EXPORT_SYMBOL(drm_sg_alloc);
189 int drm_sg_alloc_ioctl(struct drm_device *dev, void *data,
190 struct drm_file *file_priv)
192 struct drm_scatter_gather *request = data;
194 return drm_sg_alloc(dev, request);
198 int drm_sg_free(struct drm_device *dev, void *data,
199 struct drm_file *file_priv)
201 struct drm_scatter_gather *request = data;
202 struct drm_sg_mem *entry;
204 if (!drm_core_check_feature(dev, DRIVER_SG))
205 return -EINVAL;
207 entry = dev->sg;
208 dev->sg = NULL;
210 if (!entry || entry->handle != request->handle)
211 return -EINVAL;
213 DRM_DEBUG("virtual = %p\n", entry->virtual);
215 drm_sg_cleanup(entry);
217 return 0;