Linux 2.6.31-rc6
[linux-2.6] / drivers / gpu / drm / i915 / i915_mem.c
1 /* i915_mem.c -- Simple agp/fb memory manager for i915 -*- linux-c -*-
2  */
3 /*
4  * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
5  * All Rights Reserved.
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a
8  * copy of this software and associated documentation files (the
9  * "Software"), to deal in the Software without restriction, including
10  * without limitation the rights to use, copy, modify, merge, publish,
11  * distribute, sub license, and/or sell copies of the Software, and to
12  * permit persons to whom the Software is furnished to do so, subject to
13  * the following conditions:
14  *
15  * The above copyright notice and this permission notice (including the
16  * next paragraph) shall be included in all copies or substantial portions
17  * of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
21  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
22  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
23  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
24  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
25  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26  *
27  */
28
29 #include "drmP.h"
30 #include "drm.h"
31 #include "i915_drm.h"
32 #include "i915_drv.h"
33
34 /* This memory manager is integrated into the global/local lru
35  * mechanisms used by the clients.  Specifically, it operates by
36  * setting the 'in_use' fields of the global LRU to indicate whether
37  * this region is privately allocated to a client.
38  *
39  * This does require the client to actually respect that field.
40  *
41  * Currently no effort is made to allocate 'private' memory in any
42  * clever way - the LRU information isn't used to determine which
43  * block to allocate, and the ring is drained prior to allocations --
44  * in other words allocation is expensive.
45  */
46 static void mark_block(struct drm_device * dev, struct mem_block *p, int in_use)
47 {
48         drm_i915_private_t *dev_priv = dev->dev_private;
49         struct drm_i915_master_private *master_priv = dev->primary->master->driver_priv;
50         drm_i915_sarea_t *sarea_priv = master_priv->sarea_priv;
51         struct drm_tex_region *list;
52         unsigned shift, nr;
53         unsigned start;
54         unsigned end;
55         unsigned i;
56         int age;
57
58         shift = dev_priv->tex_lru_log_granularity;
59         nr = I915_NR_TEX_REGIONS;
60
61         start = p->start >> shift;
62         end = (p->start + p->size - 1) >> shift;
63
64         age = ++sarea_priv->texAge;
65         list = sarea_priv->texList;
66
67         /* Mark the regions with the new flag and update their age.  Move
68          * them to head of list to preserve LRU semantics.
69          */
70         for (i = start; i <= end; i++) {
71                 list[i].in_use = in_use;
72                 list[i].age = age;
73
74                 /* remove_from_list(i)
75                  */
76                 list[(unsigned)list[i].next].prev = list[i].prev;
77                 list[(unsigned)list[i].prev].next = list[i].next;
78
79                 /* insert_at_head(list, i)
80                  */
81                 list[i].prev = nr;
82                 list[i].next = list[nr].next;
83                 list[(unsigned)list[nr].next].prev = i;
84                 list[nr].next = i;
85         }
86 }
87
88 /* Very simple allocator for agp memory, working on a static range
89  * already mapped into each client's address space.
90  */
91
92 static struct mem_block *split_block(struct mem_block *p, int start, int size,
93                                      struct drm_file *file_priv)
94 {
95         /* Maybe cut off the start of an existing block */
96         if (start > p->start) {
97                 struct mem_block *newblock = kmalloc(sizeof(*newblock),
98                                                      GFP_KERNEL);
99                 if (!newblock)
100                         goto out;
101                 newblock->start = start;
102                 newblock->size = p->size - (start - p->start);
103                 newblock->file_priv = NULL;
104                 newblock->next = p->next;
105                 newblock->prev = p;
106                 p->next->prev = newblock;
107                 p->next = newblock;
108                 p->size -= newblock->size;
109                 p = newblock;
110         }
111
112         /* Maybe cut off the end of an existing block */
113         if (size < p->size) {
114                 struct mem_block *newblock = kmalloc(sizeof(*newblock),
115                                                      GFP_KERNEL);
116                 if (!newblock)
117                         goto out;
118                 newblock->start = start + size;
119                 newblock->size = p->size - size;
120                 newblock->file_priv = NULL;
121                 newblock->next = p->next;
122                 newblock->prev = p;
123                 p->next->prev = newblock;
124                 p->next = newblock;
125                 p->size = size;
126         }
127
128       out:
129         /* Our block is in the middle */
130         p->file_priv = file_priv;
131         return p;
132 }
133
134 static struct mem_block *alloc_block(struct mem_block *heap, int size,
135                                      int align2, struct drm_file *file_priv)
136 {
137         struct mem_block *p;
138         int mask = (1 << align2) - 1;
139
140         for (p = heap->next; p != heap; p = p->next) {
141                 int start = (p->start + mask) & ~mask;
142                 if (p->file_priv == NULL && start + size <= p->start + p->size)
143                         return split_block(p, start, size, file_priv);
144         }
145
146         return NULL;
147 }
148
149 static struct mem_block *find_block(struct mem_block *heap, int start)
150 {
151         struct mem_block *p;
152
153         for (p = heap->next; p != heap; p = p->next)
154                 if (p->start == start)
155                         return p;
156
157         return NULL;
158 }
159
160 static void free_block(struct mem_block *p)
161 {
162         p->file_priv = NULL;
163
164         /* Assumes a single contiguous range.  Needs a special file_priv in
165          * 'heap' to stop it being subsumed.
166          */
167         if (p->next->file_priv == NULL) {
168                 struct mem_block *q = p->next;
169                 p->size += q->size;
170                 p->next = q->next;
171                 p->next->prev = p;
172                 kfree(q);
173         }
174
175         if (p->prev->file_priv == NULL) {
176                 struct mem_block *q = p->prev;
177                 q->size += p->size;
178                 q->next = p->next;
179                 q->next->prev = q;
180                 kfree(p);
181         }
182 }
183
184 /* Initialize.  How to check for an uninitialized heap?
185  */
186 static int init_heap(struct mem_block **heap, int start, int size)
187 {
188         struct mem_block *blocks = kmalloc(sizeof(*blocks), GFP_KERNEL);
189
190         if (!blocks)
191                 return -ENOMEM;
192
193         *heap = kmalloc(sizeof(**heap), GFP_KERNEL);
194         if (!*heap) {
195                 kfree(blocks);
196                 return -ENOMEM;
197         }
198
199         blocks->start = start;
200         blocks->size = size;
201         blocks->file_priv = NULL;
202         blocks->next = blocks->prev = *heap;
203
204         memset(*heap, 0, sizeof(**heap));
205         (*heap)->file_priv = (struct drm_file *) - 1;
206         (*heap)->next = (*heap)->prev = blocks;
207         return 0;
208 }
209
210 /* Free all blocks associated with the releasing file.
211  */
212 void i915_mem_release(struct drm_device * dev, struct drm_file *file_priv,
213                       struct mem_block *heap)
214 {
215         struct mem_block *p;
216
217         if (!heap || !heap->next)
218                 return;
219
220         for (p = heap->next; p != heap; p = p->next) {
221                 if (p->file_priv == file_priv) {
222                         p->file_priv = NULL;
223                         mark_block(dev, p, 0);
224                 }
225         }
226
227         /* Assumes a single contiguous range.  Needs a special file_priv in
228          * 'heap' to stop it being subsumed.
229          */
230         for (p = heap->next; p != heap; p = p->next) {
231                 while (p->file_priv == NULL && p->next->file_priv == NULL) {
232                         struct mem_block *q = p->next;
233                         p->size += q->size;
234                         p->next = q->next;
235                         p->next->prev = p;
236                         kfree(q);
237                 }
238         }
239 }
240
241 /* Shutdown.
242  */
243 void i915_mem_takedown(struct mem_block **heap)
244 {
245         struct mem_block *p;
246
247         if (!*heap)
248                 return;
249
250         for (p = (*heap)->next; p != *heap;) {
251                 struct mem_block *q = p;
252                 p = p->next;
253                 kfree(q);
254         }
255
256         kfree(*heap);
257         *heap = NULL;
258 }
259
260 static struct mem_block **get_heap(drm_i915_private_t * dev_priv, int region)
261 {
262         switch (region) {
263         case I915_MEM_REGION_AGP:
264                 return &dev_priv->agp_heap;
265         default:
266                 return NULL;
267         }
268 }
269
270 /* IOCTL HANDLERS */
271
272 int i915_mem_alloc(struct drm_device *dev, void *data,
273                    struct drm_file *file_priv)
274 {
275         drm_i915_private_t *dev_priv = dev->dev_private;
276         drm_i915_mem_alloc_t *alloc = data;
277         struct mem_block *block, **heap;
278
279         if (!dev_priv) {
280                 DRM_ERROR("called with no initialization\n");
281                 return -EINVAL;
282         }
283
284         heap = get_heap(dev_priv, alloc->region);
285         if (!heap || !*heap)
286                 return -EFAULT;
287
288         /* Make things easier on ourselves: all allocations at least
289          * 4k aligned.
290          */
291         if (alloc->alignment < 12)
292                 alloc->alignment = 12;
293
294         block = alloc_block(*heap, alloc->size, alloc->alignment, file_priv);
295
296         if (!block)
297                 return -ENOMEM;
298
299         mark_block(dev, block, 1);
300
301         if (DRM_COPY_TO_USER(alloc->region_offset, &block->start,
302                              sizeof(int))) {
303                 DRM_ERROR("copy_to_user\n");
304                 return -EFAULT;
305         }
306
307         return 0;
308 }
309
310 int i915_mem_free(struct drm_device *dev, void *data,
311                   struct drm_file *file_priv)
312 {
313         drm_i915_private_t *dev_priv = dev->dev_private;
314         drm_i915_mem_free_t *memfree = data;
315         struct mem_block *block, **heap;
316
317         if (!dev_priv) {
318                 DRM_ERROR("called with no initialization\n");
319                 return -EINVAL;
320         }
321
322         heap = get_heap(dev_priv, memfree->region);
323         if (!heap || !*heap)
324                 return -EFAULT;
325
326         block = find_block(*heap, memfree->region_offset);
327         if (!block)
328                 return -EFAULT;
329
330         if (block->file_priv != file_priv)
331                 return -EPERM;
332
333         mark_block(dev, block, 0);
334         free_block(block);
335         return 0;
336 }
337
338 int i915_mem_init_heap(struct drm_device *dev, void *data,
339                        struct drm_file *file_priv)
340 {
341         drm_i915_private_t *dev_priv = dev->dev_private;
342         drm_i915_mem_init_heap_t *initheap = data;
343         struct mem_block **heap;
344
345         if (!dev_priv) {
346                 DRM_ERROR("called with no initialization\n");
347                 return -EINVAL;
348         }
349
350         heap = get_heap(dev_priv, initheap->region);
351         if (!heap)
352                 return -EFAULT;
353
354         if (*heap) {
355                 DRM_ERROR("heap already initialized?");
356                 return -EFAULT;
357         }
358
359         return init_heap(heap, initheap->start, initheap->size);
360 }
361
362 int i915_mem_destroy_heap( struct drm_device *dev, void *data,
363                            struct drm_file *file_priv )
364 {
365         drm_i915_private_t *dev_priv = dev->dev_private;
366         drm_i915_mem_destroy_heap_t *destroyheap = data;
367         struct mem_block **heap;
368
369         if ( !dev_priv ) {
370                 DRM_ERROR( "called with no initialization\n" );
371                 return -EINVAL;
372         }
373
374         heap = get_heap( dev_priv, destroyheap->region );
375         if (!heap) {
376                 DRM_ERROR("get_heap failed");
377                 return -EFAULT;
378         }
379
380         if (!*heap) {
381                 DRM_ERROR("heap not initialized?");
382                 return -EFAULT;
383         }
384
385         i915_mem_takedown( heap );
386         return 0;
387 }