xref: /netbsd-src/sys/external/bsd/drm/dist/shared-core/i915_mem.c (revision d582952b835d6fd0bdb8105c2e2b285a31f76c2d)
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  */
mark_block(struct drm_device * dev,struct mem_block * p,int in_use)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 	drm_i915_sarea_t *sarea_priv = dev_priv->sarea_priv;
50 	struct drm_tex_region *list;
51 	unsigned shift, nr;
52 	unsigned start;
53 	unsigned end;
54 	unsigned i;
55 	int age;
56 
57 	shift = dev_priv->tex_lru_log_granularity;
58 	nr = I915_NR_TEX_REGIONS;
59 
60 	start = p->start >> shift;
61 	end = (p->start + p->size - 1) >> shift;
62 
63 	age = ++sarea_priv->texAge;
64 	list = sarea_priv->texList;
65 
66 	/* Mark the regions with the new flag and update their age.  Move
67 	 * them to head of list to preserve LRU semantics.
68 	 */
69 	for (i = start; i <= end; i++) {
70 		list[i].in_use = in_use;
71 		list[i].age = age;
72 
73 		/* remove_from_list(i)
74 		 */
75 		list[(unsigned)list[i].next].prev = list[i].prev;
76 		list[(unsigned)list[i].prev].next = list[i].next;
77 
78 		/* insert_at_head(list, i)
79 		 */
80 		list[i].prev = nr;
81 		list[i].next = list[nr].next;
82 		list[(unsigned)list[nr].next].prev = i;
83 		list[nr].next = i;
84 	}
85 }
86 
87 /* Very simple allocator for agp memory, working on a static range
88  * already mapped into each client's address space.
89  */
90 
split_block(struct mem_block * p,int start,int size,struct drm_file * file_priv)91 static struct mem_block *split_block(struct mem_block *p, int start, int size,
92 				     struct drm_file *file_priv)
93 {
94 	/* Maybe cut off the start of an existing block */
95 	if (start > p->start) {
96 		struct mem_block *newblock =
97 		    drm_alloc(sizeof(*newblock), DRM_MEM_BUFLISTS);
98 		if (!newblock)
99 			goto out;
100 		newblock->start = start;
101 		newblock->size = p->size - (start - p->start);
102 		newblock->file_priv = NULL;
103 		newblock->next = p->next;
104 		newblock->prev = p;
105 		p->next->prev = newblock;
106 		p->next = newblock;
107 		p->size -= newblock->size;
108 		p = newblock;
109 	}
110 
111 	/* Maybe cut off the end of an existing block */
112 	if (size < p->size) {
113 		struct mem_block *newblock =
114 		    drm_alloc(sizeof(*newblock), DRM_MEM_BUFLISTS);
115 		if (!newblock)
116 			goto out;
117 		newblock->start = start + size;
118 		newblock->size = p->size - size;
119 		newblock->file_priv = NULL;
120 		newblock->next = p->next;
121 		newblock->prev = p;
122 		p->next->prev = newblock;
123 		p->next = newblock;
124 		p->size = size;
125 	}
126 
127       out:
128 	/* Our block is in the middle */
129 	p->file_priv = file_priv;
130 	return p;
131 }
132 
alloc_block(struct mem_block * heap,int size,int align2,struct drm_file * file_priv)133 static struct mem_block *alloc_block(struct mem_block *heap, int size,
134 				     int align2, struct drm_file *file_priv)
135 {
136 	struct mem_block *p;
137 	int mask = (1 << align2) - 1;
138 
139 	for (p = heap->next; p != heap; p = p->next) {
140 		int start = (p->start + mask) & ~mask;
141 		if (p->file_priv == NULL && start + size <= p->start + p->size)
142 			return split_block(p, start, size, file_priv);
143 	}
144 
145 	return NULL;
146 }
147 
find_block(struct mem_block * heap,int start)148 static struct mem_block *find_block(struct mem_block *heap, int start)
149 {
150 	struct mem_block *p;
151 
152 	for (p = heap->next; p != heap; p = p->next)
153 		if (p->start == start)
154 			return p;
155 
156 	return NULL;
157 }
158 
free_block(struct mem_block * p)159 static void free_block(struct mem_block *p)
160 {
161 	p->file_priv = NULL;
162 
163 	/* Assumes a single contiguous range.  Needs a special file_priv in
164 	 * 'heap' to stop it being subsumed.
165 	 */
166 	if (p->next->file_priv == NULL) {
167 		struct mem_block *q = p->next;
168 		p->size += q->size;
169 		p->next = q->next;
170 		p->next->prev = p;
171 		drm_free(q, sizeof(*q), DRM_MEM_BUFLISTS);
172 	}
173 
174 	if (p->prev->file_priv == NULL) {
175 		struct mem_block *q = p->prev;
176 		q->size += p->size;
177 		q->next = p->next;
178 		q->next->prev = q;
179 		drm_free(p, sizeof(*q), DRM_MEM_BUFLISTS);
180 	}
181 }
182 
183 /* Initialize.  How to check for an uninitialized heap?
184  */
init_heap(struct mem_block ** heap,int start,int size)185 static int init_heap(struct mem_block **heap, int start, int size)
186 {
187 	struct mem_block *blocks = drm_alloc(sizeof(*blocks), DRM_MEM_BUFLISTS);
188 
189 	if (!blocks)
190 		return -ENOMEM;
191 
192 	*heap = drm_alloc(sizeof(**heap), DRM_MEM_BUFLISTS);
193 	if (!*heap) {
194 		drm_free(blocks, sizeof(*blocks), DRM_MEM_BUFLISTS);
195 		return -ENOMEM;
196 	}
197 
198 	blocks->start = start;
199 	blocks->size = size;
200 	blocks->file_priv = NULL;
201 	blocks->next = blocks->prev = *heap;
202 
203 	memset(*heap, 0, sizeof(**heap));
204 	(*heap)->file_priv = (struct drm_file *) - 1;
205 	(*heap)->next = (*heap)->prev = blocks;
206 	return 0;
207 }
208 
209 /* Free all blocks associated with the releasing file.
210  */
i915_mem_release(struct drm_device * dev,struct drm_file * file_priv,struct mem_block * heap)211 void i915_mem_release(struct drm_device * dev, struct drm_file *file_priv,
212 		      struct mem_block *heap)
213 {
214 	struct mem_block *p;
215 
216 	if (!heap || !heap->next)
217 		return;
218 
219 	for (p = heap->next; p != heap; p = p->next) {
220 		if (p->file_priv == file_priv) {
221 			p->file_priv = NULL;
222 			mark_block(dev, p, 0);
223 		}
224 	}
225 
226 	/* Assumes a single contiguous range.  Needs a special file_priv in
227 	 * 'heap' to stop it being subsumed.
228 	 */
229 	for (p = heap->next; p != heap; p = p->next) {
230 		while (p->file_priv == NULL && p->next->file_priv == NULL) {
231 			struct mem_block *q = p->next;
232 			p->size += q->size;
233 			p->next = q->next;
234 			p->next->prev = p;
235 			drm_free(q, sizeof(*q), DRM_MEM_BUFLISTS);
236 		}
237 	}
238 }
239 
240 /* Shutdown.
241  */
i915_mem_takedown(struct mem_block ** heap)242 void i915_mem_takedown(struct mem_block **heap)
243 {
244 	struct mem_block *p;
245 
246 	if (!*heap)
247 		return;
248 
249 	for (p = (*heap)->next; p != *heap;) {
250 		struct mem_block *q = p;
251 		p = p->next;
252 		drm_free(q, sizeof(*q), DRM_MEM_BUFLISTS);
253 	}
254 
255 	drm_free(*heap, sizeof(**heap), DRM_MEM_BUFLISTS);
256 	*heap = NULL;
257 }
258 
get_heap(drm_i915_private_t * dev_priv,int region)259 static struct mem_block **get_heap(drm_i915_private_t * dev_priv, int region)
260 {
261 	switch (region) {
262 	case I915_MEM_REGION_AGP:
263 		return &dev_priv->agp_heap;
264 	default:
265 		return NULL;
266 	}
267 }
268 
269 /* IOCTL HANDLERS */
270 
i915_mem_alloc(struct drm_device * dev,void * data,struct drm_file * file_priv)271 int i915_mem_alloc(struct drm_device *dev, void *data,
272 		   struct drm_file *file_priv)
273 {
274 	drm_i915_private_t *dev_priv = dev->dev_private;
275 	drm_i915_mem_alloc_t *alloc = data;
276 	struct mem_block *block, **heap;
277 
278 	if (!dev_priv) {
279 		DRM_ERROR("called with no initialization\n");
280 		return -EINVAL;
281 	}
282 
283 	heap = get_heap(dev_priv, alloc->region);
284 	if (!heap || !*heap)
285 		return -EFAULT;
286 
287 	/* Make things easier on ourselves: all allocations at least
288 	 * 4k aligned.
289 	 */
290 	if (alloc->alignment < 12)
291 		alloc->alignment = 12;
292 
293 	block = alloc_block(*heap, alloc->size, alloc->alignment, file_priv);
294 
295 	if (!block)
296 		return -ENOMEM;
297 
298 	mark_block(dev, block, 1);
299 
300 	if (DRM_COPY_TO_USER(alloc->region_offset, &block->start,
301 			     sizeof(int))) {
302 		DRM_ERROR("copy_to_user\n");
303 		return -EFAULT;
304 	}
305 
306 	return 0;
307 }
308 
i915_mem_free(struct drm_device * dev,void * data,struct drm_file * file_priv)309 int i915_mem_free(struct drm_device *dev, void *data,
310 		  struct drm_file *file_priv)
311 {
312 	drm_i915_private_t *dev_priv = dev->dev_private;
313 	drm_i915_mem_free_t *memfree = data;
314 	struct mem_block *block, **heap;
315 
316 	if (!dev_priv) {
317 		DRM_ERROR("called with no initialization\n");
318 		return -EINVAL;
319 	}
320 
321 	heap = get_heap(dev_priv, memfree->region);
322 	if (!heap || !*heap)
323 		return -EFAULT;
324 
325 	block = find_block(*heap, memfree->region_offset);
326 	if (!block)
327 		return -EFAULT;
328 
329 	if (block->file_priv != file_priv)
330 		return -EPERM;
331 
332 	mark_block(dev, block, 0);
333 	free_block(block);
334 	return 0;
335 }
336 
i915_mem_init_heap(struct drm_device * dev,void * data,struct drm_file * file_priv)337 int i915_mem_init_heap(struct drm_device *dev, void *data,
338 		       struct drm_file *file_priv)
339 {
340 	drm_i915_private_t *dev_priv = dev->dev_private;
341 	drm_i915_mem_init_heap_t *initheap = data;
342 	struct mem_block **heap;
343 
344 	if (!dev_priv) {
345 		DRM_ERROR("called with no initialization\n");
346 		return -EINVAL;
347 	}
348 
349 	heap = get_heap(dev_priv, initheap->region);
350 	if (!heap)
351 		return -EFAULT;
352 
353 	if (*heap) {
354 		DRM_ERROR("heap already initialized?");
355 		return -EFAULT;
356 	}
357 
358 	return init_heap(heap, initheap->start, initheap->size);
359 }
360 
i915_mem_destroy_heap(struct drm_device * dev,void * data,struct drm_file * file_priv)361 int i915_mem_destroy_heap( struct drm_device *dev, void *data,
362 			   struct drm_file *file_priv )
363 {
364 	drm_i915_private_t *dev_priv = dev->dev_private;
365 	drm_i915_mem_destroy_heap_t *destroyheap = data;
366 	struct mem_block **heap;
367 
368 	if ( !dev_priv ) {
369 		DRM_ERROR( "called with no initialization\n" );
370 		return -EINVAL;
371 	}
372 
373 	heap = get_heap( dev_priv, destroyheap->region );
374 	if (!heap) {
375 		DRM_ERROR("get_heap failed");
376 		return -EFAULT;
377 	}
378 
379 	if (!*heap) {
380 		DRM_ERROR("heap not initialized?");
381 		return -EFAULT;
382 	}
383 
384 	i915_mem_takedown( heap );
385 	return 0;
386 }
387