GNU Linux-libre 5.10.219-gnu1
[releases.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/mm.h>
35 #include <linux/slab.h>
36 #include <linux/vmalloc.h>
37
38 #include <drm/drm.h>
39 #include <drm/drm_drv.h>
40 #include <drm/drm_print.h>
41
42 #include "drm_legacy.h"
43
44 #define DEBUG_SCATTER 0
45
46 static void drm_sg_cleanup(struct drm_sg_mem * entry)
47 {
48         struct page *page;
49         int i;
50
51         for (i = 0; i < entry->pages; i++) {
52                 page = entry->pagelist[i];
53                 if (page)
54                         ClearPageReserved(page);
55         }
56
57         vfree(entry->virtual);
58
59         kfree(entry->busaddr);
60         kfree(entry->pagelist);
61         kfree(entry);
62 }
63
64 void drm_legacy_sg_cleanup(struct drm_device *dev)
65 {
66         if (drm_core_check_feature(dev, DRIVER_SG) && dev->sg &&
67             drm_core_check_feature(dev, DRIVER_LEGACY)) {
68                 drm_sg_cleanup(dev->sg);
69                 dev->sg = NULL;
70         }
71 }
72 #ifdef _LP64
73 # define ScatterHandle(x) (unsigned int)((x >> 32) + (x & ((1L << 32) - 1)))
74 #else
75 # define ScatterHandle(x) (unsigned int)(x)
76 #endif
77
78 int drm_legacy_sg_alloc(struct drm_device *dev, void *data,
79                         struct drm_file *file_priv)
80 {
81         struct drm_scatter_gather *request = data;
82         struct drm_sg_mem *entry;
83         unsigned long pages, i, j;
84
85         DRM_DEBUG("\n");
86
87         if (!drm_core_check_feature(dev, DRIVER_LEGACY))
88                 return -EOPNOTSUPP;
89
90         if (!drm_core_check_feature(dev, DRIVER_SG))
91                 return -EOPNOTSUPP;
92
93         if (request->size > SIZE_MAX - PAGE_SIZE)
94                 return -EINVAL;
95
96         if (dev->sg)
97                 return -EINVAL;
98
99         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
100         if (!entry)
101                 return -ENOMEM;
102
103         pages = (request->size + PAGE_SIZE - 1) / PAGE_SIZE;
104         DRM_DEBUG("size=%ld pages=%ld\n", request->size, pages);
105
106         entry->pages = pages;
107         entry->pagelist = kcalloc(pages, sizeof(*entry->pagelist), GFP_KERNEL);
108         if (!entry->pagelist) {
109                 kfree(entry);
110                 return -ENOMEM;
111         }
112
113         entry->busaddr = kcalloc(pages, sizeof(*entry->busaddr), GFP_KERNEL);
114         if (!entry->busaddr) {
115                 kfree(entry->pagelist);
116                 kfree(entry);
117                 return -ENOMEM;
118         }
119
120         entry->virtual = vmalloc_32(pages << PAGE_SHIFT);
121         if (!entry->virtual) {
122                 kfree(entry->busaddr);
123                 kfree(entry->pagelist);
124                 kfree(entry);
125                 return -ENOMEM;
126         }
127
128         /* This also forces the mapping of COW pages, so our page list
129          * will be valid.  Please don't remove it...
130          */
131         memset(entry->virtual, 0, pages << PAGE_SHIFT);
132
133         entry->handle = ScatterHandle((unsigned long)entry->virtual);
134
135         DRM_DEBUG("handle  = %08lx\n", entry->handle);
136         DRM_DEBUG("virtual = %p\n", entry->virtual);
137
138         for (i = (unsigned long)entry->virtual, j = 0; j < pages;
139              i += PAGE_SIZE, j++) {
140                 entry->pagelist[j] = vmalloc_to_page((void *)i);
141                 if (!entry->pagelist[j])
142                         goto failed;
143                 SetPageReserved(entry->pagelist[j]);
144         }
145
146         request->handle = entry->handle;
147
148         dev->sg = entry;
149
150 #if DEBUG_SCATTER
151         /* Verify that each page points to its virtual address, and vice
152          * versa.
153          */
154         {
155                 int error = 0;
156
157                 for (i = 0; i < pages; i++) {
158                         unsigned long *tmp;
159
160                         tmp = page_address(entry->pagelist[i]);
161                         for (j = 0;
162                              j < PAGE_SIZE / sizeof(unsigned long);
163                              j++, tmp++) {
164                                 *tmp = 0xcafebabe;
165                         }
166                         tmp = (unsigned long *)((u8 *) entry->virtual +
167                                                 (PAGE_SIZE * i));
168                         for (j = 0;
169                              j < PAGE_SIZE / sizeof(unsigned long);
170                              j++, tmp++) {
171                                 if (*tmp != 0xcafebabe && error == 0) {
172                                         error = 1;
173                                         DRM_ERROR("Scatter allocation error, "
174                                                   "pagelist does not match "
175                                                   "virtual mapping\n");
176                                 }
177                         }
178                         tmp = page_address(entry->pagelist[i]);
179                         for (j = 0;
180                              j < PAGE_SIZE / sizeof(unsigned long);
181                              j++, tmp++) {
182                                 *tmp = 0;
183                         }
184                 }
185                 if (error == 0)
186                         DRM_ERROR("Scatter allocation matches pagelist\n");
187         }
188 #endif
189
190         return 0;
191
192       failed:
193         drm_sg_cleanup(entry);
194         return -ENOMEM;
195 }
196
197 int drm_legacy_sg_free(struct drm_device *dev, void *data,
198                        struct drm_file *file_priv)
199 {
200         struct drm_scatter_gather *request = data;
201         struct drm_sg_mem *entry;
202
203         if (!drm_core_check_feature(dev, DRIVER_LEGACY))
204                 return -EOPNOTSUPP;
205
206         if (!drm_core_check_feature(dev, DRIVER_SG))
207                 return -EOPNOTSUPP;
208
209         entry = dev->sg;
210         dev->sg = NULL;
211
212         if (!entry || entry->handle != request->handle)
213                 return -EINVAL;
214
215         DRM_DEBUG("virtual  = %p\n", entry->virtual);
216
217         drm_sg_cleanup(entry);
218
219         return 0;
220 }