[linux-2.6-block.git] / drivers / char / drm / i915_mem.c

/* i915_mem.c -- Simple agp/fb memory manager for i915 -*- linux-c -*-
 */
/**************************************************************************
 *
 * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 **************************************************************************/

#include "drmP.h"
#include "drm.h"
#include "i915_drm.h"
#include "i915_drv.h"

/* This memory manager is integrated into the global/local lru
 * mechanisms used by the clients.  Specifically, it operates by
 * setting the 'in_use' fields of the global LRU to indicate whether
 * this region is privately allocated to a client.
 *
 * This does require the client to actually respect that field.
 *
 * Currently no effort is made to allocate 'private' memory in any
 * clever way - the LRU information isn't used to determine which
 * block to allocate, and the ring is drained prior to allocations --
 * in other words allocation is expensive.
 */
static void mark_block(drm_device_t * dev, struct mem_block *p, int in_use)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	drm_i915_sarea_t *sarea_priv = dev_priv->sarea_priv;
	drm_tex_region_t *list;
	unsigned shift, nr;
	unsigned start;
	unsigned end;
	unsigned i;
	int age;

	shift = dev_priv->tex_lru_log_granularity;
	nr = I915_NR_TEX_REGIONS;

	start = p->start >> shift;
	end = (p->start + p->size - 1) >> shift;

	age = ++sarea_priv->texAge;
	list = sarea_priv->texList;

	/* Mark the regions with the new flag and update their age.  Move
	 * them to head of list to preserve LRU semantics.
	 */
	for (i = start; i <= end; i++) {
		list[i].in_use = in_use;
		list[i].age = age;

		/* remove_from_list(i)
		 */
		list[(unsigned)list[i].next].prev = list[i].prev;
		list[(unsigned)list[i].prev].next = list[i].next;

		/* insert_at_head(list, i)
		 */
		list[i].prev = nr;
		list[i].next = list[nr].next;
		list[(unsigned)list[nr].next].prev = i;
		list[nr].next = i;
	}
}

/* Very simple allocator for agp memory, working on a static range
 * already mapped into each client's address space.  
 */

static struct mem_block *split_block(struct mem_block *p, int start, int size,
				     DRMFILE filp)
{
	/* Maybe cut off the start of an existing block */
	if (start > p->start) {
		struct mem_block *newblock = drm_alloc(sizeof(*newblock), DRM_MEM_BUFLISTS);
		if (!newblock)
			goto out;
		newblock->start = start;
		newblock->size = p->size - (start - p->start);
		newblock->filp = NULL;
		newblock->next = p->next;
		newblock->prev = p;
		p->next->prev = newblock;
		p->next = newblock;
		p->size -= newblock->size;
		p = newblock;
	}

	/* Maybe cut off the end of an existing block */
	if (size < p->size) {
		struct mem_block *newblock = drm_alloc(sizeof(*newblock), DRM_MEM_BUFLISTS);
		if (!newblock)
			goto out;
		newblock->start = start + size;
		newblock->size = p->size - size;
		newblock->filp = NULL;
		newblock->next = p->next;
		newblock->prev = p;
		p->next->prev = newblock;
		p->next = newblock;
		p->size = size;
	}

      out:
	/* Our block is in the middle */
	p->filp = filp;
	return p;
}

static struct mem_block *alloc_block(struct mem_block *heap, int size,
				     int align2, DRMFILE filp)
{
	struct mem_block *p;
	int mask = (1 << align2) - 1;

	for (p = heap->next; p != heap; p = p->next) {
		int start = (p->start + mask) & ~mask;
		if (p->filp == NULL && start + size <= p->start + p->size)
			return split_block(p, start, size, filp);
	}

	return NULL;
}

static struct mem_block *find_block(struct mem_block *heap, int start)
{
	struct mem_block *p;

	for (p = heap->next; p != heap; p = p->next)
		if (p->start == start)
			return p;

	return NULL;
}

static void free_block(struct mem_block *p)
{
	p->filp = NULL;

	/* Assumes a single contiguous range.  Needs a special filp in
	 * 'heap' to stop it being subsumed.
	 */
	if (p->next->filp == NULL) {
		struct mem_block *q = p->next;
		p->size += q->size;
		p->next = q->next;
		p->next->prev = p;
		drm_free(q, sizeof(*q), DRM_MEM_BUFLISTS);
	}

	if (p->prev->filp == NULL) {
		struct mem_block *q = p->prev;
		q->size += p->size;
		q->next = p->next;
		q->next->prev = q;
		drm_free(p, sizeof(*q), DRM_MEM_BUFLISTS);
	}
}

/* Initialize.  How to check for an uninitialized heap?
 */
static int init_heap(struct mem_block **heap, int start, int size)
{
	struct mem_block *blocks = drm_alloc(sizeof(*blocks), DRM_MEM_BUFLISTS);

	if (!blocks)
		return -ENOMEM;

	*heap = drm_alloc(sizeof(**heap), DRM_MEM_BUFLISTS);
	if (!*heap) {
		drm_free(blocks, sizeof(*blocks), DRM_MEM_BUFLISTS);
		return -ENOMEM;
	}

	blocks->start = start;
	blocks->size = size;
	blocks->filp = NULL;
	blocks->next = blocks->prev = *heap;

	memset(*heap, 0, sizeof(**heap));
	(*heap)->filp = (DRMFILE) - 1;
	(*heap)->next = (*heap)->prev = blocks;
	return 0;
}

/* Free all blocks associated with the releasing file.
 */
void i915_mem_release(drm_device_t * dev, DRMFILE filp, struct mem_block *heap)
{
	struct mem_block *p;

	if (!heap || !heap->next)
		return;

	for (p = heap->next; p != heap; p = p->next) {
		if (p->filp == filp) {
			p->filp = NULL;
			mark_block(dev, p, 0);
		}
	}

	/* Assumes a single contiguous range.  Needs a special filp in
	 * 'heap' to stop it being subsumed.
	 */
	for (p = heap->next; p != heap; p = p->next) {
		while (p->filp == NULL && p->next->filp == NULL) {
			struct mem_block *q = p->next;
			p->size += q->size;
			p->next = q->next;
			p->next->prev = p;
			drm_free(q, sizeof(*q), DRM_MEM_BUFLISTS);
		}
	}
}

/* Shutdown.
 */
void i915_mem_takedown(struct mem_block **heap)
{
	struct mem_block *p;

	if (!*heap)
		return;

	for (p = (*heap)->next; p != *heap;) {
		struct mem_block *q = p;
		p = p->next;
		drm_free(q, sizeof(*q), DRM_MEM_BUFLISTS);
	}

	drm_free(*heap, sizeof(**heap), DRM_MEM_BUFLISTS);
	*heap = NULL;
}

static struct mem_block **get_heap(drm_i915_private_t * dev_priv, int region)
{
	switch (region) {
	case I915_MEM_REGION_AGP:
		return &dev_priv->agp_heap;
	default:
		return NULL;
	}
}

/* IOCTL HANDLERS */

int i915_mem_alloc(DRM_IOCTL_ARGS)
{
	DRM_DEVICE;
	drm_i915_private_t *dev_priv = dev->dev_private;
	drm_i915_mem_alloc_t alloc;
	struct mem_block *block, **heap;

	if (!dev_priv) {
		DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
		return DRM_ERR(EINVAL);
	}

	DRM_COPY_FROM_USER_IOCTL(alloc, (drm_i915_mem_alloc_t __user *) data,
				 sizeof(alloc));

	heap = get_heap(dev_priv, alloc.region);
	if (!heap || !*heap)
		return DRM_ERR(EFAULT);

	/* Make things easier on ourselves: all allocations at least
	 * 4k aligned.
	 */
	if (alloc.alignment < 12)
		alloc.alignment = 12;

	block = alloc_block(*heap, alloc.size, alloc.alignment, filp);

	if (!block)
		return DRM_ERR(ENOMEM);

	mark_block(dev, block, 1);

	if (DRM_COPY_TO_USER(alloc.region_offset, &block->start, sizeof(int))) {
		DRM_ERROR("copy_to_user\n");
		return DRM_ERR(EFAULT);
	}

	return 0;
}

int i915_mem_free(DRM_IOCTL_ARGS)
{
	DRM_DEVICE;
	drm_i915_private_t *dev_priv = dev->dev_private;
	drm_i915_mem_free_t memfree;
	struct mem_block *block, **heap;

	if (!dev_priv) {
		DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
		return DRM_ERR(EINVAL);
	}

	DRM_COPY_FROM_USER_IOCTL(memfree, (drm_i915_mem_free_t __user *) data,
				 sizeof(memfree));

	heap = get_heap(dev_priv, memfree.region);
	if (!heap || !*heap)
		return DRM_ERR(EFAULT);

	block = find_block(*heap, memfree.region_offset);
	if (!block)
		return DRM_ERR(EFAULT);

	if (block->filp != filp)
		return DRM_ERR(EPERM);

	mark_block(dev, block, 0);
	free_block(block);
	return 0;
}

int i915_mem_init_heap(DRM_IOCTL_ARGS)
{
	DRM_DEVICE;
	drm_i915_private_t *dev_priv = dev->dev_private;
	drm_i915_mem_init_heap_t initheap;
	struct mem_block **heap;

	if (!dev_priv) {
		DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
		return DRM_ERR(EINVAL);
	}

	DRM_COPY_FROM_USER_IOCTL(initheap,
				 (drm_i915_mem_init_heap_t __user *) data,
				 sizeof(initheap));

	heap = get_heap(dev_priv, initheap.region);
	if (!heap)
		return DRM_ERR(EFAULT);

	if (*heap) {
		DRM_ERROR("heap already initialized?");
		return DRM_ERR(EFAULT);
	}

	return init_heap(heap, initheap.start, initheap.size);
}
Commit	Line	Data
1da177e4 LT	1	/* i915_mem.c -- Simple agp/fb memory manager for i915 -- linux-c --
	2	*/
	3	/**************************************************************************
bc54fd1a	4	*
1da177e4 LT	5	* Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
1da177e4 LT	6	* All Rights Reserved.
bc54fd1a DA	7	*
	8	* Permission is hereby granted, free of charge, to any person obtaining a
	9	* copy of this software and associated documentation files (the
	10	* "Software"), to deal in the Software without restriction, including
	11	* without limitation the rights to use, copy, modify, merge, publish,
	12	* distribute, sub license, and/or sell copies of the Software, and to
	13	* permit persons to whom the Software is furnished to do so, subject to
	14	* the following conditions:
	15	*
	16	* The above copyright notice and this permission notice (including the
	17	* next paragraph) shall be included in all copies or substantial portions
	18	* of the Software.
	19	*
	20	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
	21	* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	22	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
	23	* IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
	24	* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
	25	* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
	26	* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	27	*
1da177e4 LT	28	**************************************************************************/
	29
	30	#include "drmP.h"
	31	#include "drm.h"
	32	#include "i915_drm.h"
	33	#include "i915_drv.h"
	34
	35	/* This memory manager is integrated into the global/local lru
	36	* mechanisms used by the clients. Specifically, it operates by
	37	* setting the 'in_use' fields of the global LRU to indicate whether
	38	* this region is privately allocated to a client.
	39	*
	40	* This does require the client to actually respect that field.
	41	*
	42	* Currently no effort is made to allocate 'private' memory in any
	43	* clever way - the LRU information isn't used to determine which
	44	* block to allocate, and the ring is drained prior to allocations --
	45	* in other words allocation is expensive.
	46	*/
	47	static void mark_block(drm_device_t * dev, struct mem_block *p, int in_use)
	48	{
	49	drm_i915_private_t *dev_priv = dev->dev_private;
	50	drm_i915_sarea_t *sarea_priv = dev_priv->sarea_priv;
	51	drm_tex_region_t *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	DRMFILE filp)
94	{
95	/* Maybe cut off the start of an existing block */
96	if (start > p->start) {
97	struct mem_block newblock = 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->filp = 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 = drm_alloc(sizeof(newblock), DRM_MEM_BUFLISTS);
114	if (!newblock)
115	goto out;
116	newblock->start = start + size;
117	newblock->size = p->size - size;
118	newblock->filp = NULL;
119	newblock->next = p->next;
120	newblock->prev = p;
121	p->next->prev = newblock;
122	p->next = newblock;
123	p->size = size;
124	}
125
126	out:
127	/* Our block is in the middle */
128	p->filp = filp;
129	return p;
130	}
131
132	static struct mem_block alloc_block(struct mem_block heap, int size,
133	int align2, DRMFILE filp)
134	{
135	struct mem_block *p;
136	int mask = (1 << align2) - 1;
137
138	for (p = heap->next; p != heap; p = p->next) {
139	int start = (p->start + mask) & ~mask;
140	if (p->filp == NULL && start + size <= p->start + p->size)
141	return split_block(p, start, size, filp);
142	}
143
144	return NULL;
145	}
146
147	static struct mem_block find_block(struct mem_block heap, int start)
148	{
149	struct mem_block *p;
150
151	for (p = heap->next; p != heap; p = p->next)
152	if (p->start == start)
153	return p;
154
155	return NULL;
156	}
157
158	static void free_block(struct mem_block *p)
159	{
160	p->filp = NULL;
161
162	/* Assumes a single contiguous range. Needs a special filp in
163	* 'heap' to stop it being subsumed.
164	*/
165	if (p->next->filp == NULL) {
166	struct mem_block *q = p->next;
167	p->size += q->size;
168	p->next = q->next;
169	p->next->prev = p;
170	drm_free(q, sizeof(*q), DRM_MEM_BUFLISTS);
171	}
172
173	if (p->prev->filp == NULL) {
174	struct mem_block *q = p->prev;
175	q->size += p->size;
176	q->next = p->next;
177	q->next->prev = q;
178	drm_free(p, sizeof(*q), DRM_MEM_BUFLISTS);
179	}
180	}
181
182	/* Initialize. How to check for an uninitialized heap?
183	*/
184	static int init_heap(struct mem_block **heap, int start, int size)
185	{
186	struct mem_block blocks = drm_alloc(sizeof(blocks), DRM_MEM_BUFLISTS);
187
188	if (!blocks)
189	return -ENOMEM;
190
191	heap = drm_alloc(sizeof(*heap), DRM_MEM_BUFLISTS);
192	if (!*heap) {
193	drm_free(blocks, sizeof(*blocks), DRM_MEM_BUFLISTS);
194	return -ENOMEM;
195	}
196
197	blocks->start = start;
198	blocks->size = size;
199	blocks->filp = NULL;
200	blocks->next = blocks->prev = *heap;
201
202	memset(heap, 0, sizeof(*heap));
203	(*heap)->filp = (DRMFILE) - 1;
204	(heap)->next = (heap)->prev = blocks;
205	return 0;
206	}
207
208	/* Free all blocks associated with the releasing file.
209	*/
210	void i915_mem_release(drm_device_t * dev, DRMFILE filp, struct mem_block *heap)
211	{
212	struct mem_block *p;
213
214	if (!heap \|\| !heap->next)
215	return;
216
217	for (p = heap->next; p != heap; p = p->next) {
218	if (p->filp == filp) {
219	p->filp = NULL;
220	mark_block(dev, p, 0);
221	}
222	}
223
224	/* Assumes a single contiguous range. Needs a special filp in
225	* 'heap' to stop it being subsumed.
226	*/
227	for (p = heap->next; p != heap; p = p->next) {
228	while (p->filp == NULL && p->next->filp == NULL) {
229	struct mem_block *q = p->next;
230	p->size += q->size;
231	p->next = q->next;
232	p->next->prev = p;
233	drm_free(q, sizeof(*q), DRM_MEM_BUFLISTS);
234	}
235	}
236	}
237
238	/* Shutdown.
239	*/
240	void i915_mem_takedown(struct mem_block **heap)
241	{
242	struct mem_block *p;
243
244	if (!*heap)
245	return;
246
247	for (p = (heap)->next; p != heap;) {
248	struct mem_block *q = p;
249	p = p->next;
250	drm_free(q, sizeof(*q), DRM_MEM_BUFLISTS);
251	}
252
253	drm_free(heap, sizeof(*heap), DRM_MEM_BUFLISTS);
254	*heap = NULL;
255	}
256
257	static struct mem_block *get_heap(drm_i915_private_t dev_priv, int region)
258	{
259	switch (region) {
260	case I915_MEM_REGION_AGP:
261	return &dev_priv->agp_heap;
262	default:
263	return NULL;
264	}
265	}
266
267	/* IOCTL HANDLERS */
268
269	int i915_mem_alloc(DRM_IOCTL_ARGS)
270	{
271	DRM_DEVICE;
272	drm_i915_private_t *dev_priv = dev->dev_private;
273	drm_i915_mem_alloc_t alloc;
274	struct mem_block block, *heap;
275
276	if (!dev_priv) {
277	DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
278	return DRM_ERR(EINVAL);
279	}
280
281	DRM_COPY_FROM_USER_IOCTL(alloc, (drm_i915_mem_alloc_t __user *) data,
282	sizeof(alloc));
283
284	heap = get_heap(dev_priv, alloc.region);
285	if (!heap \|\| !*heap)
286	return DRM_ERR(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, filp);
295
296	if (!block)
297	return DRM_ERR(ENOMEM);
298
299	mark_block(dev, block, 1);
300
301	if (DRM_COPY_TO_USER(alloc.region_offset, &block->start, sizeof(int))) {
302	DRM_ERROR("copy_to_user\n");
303	return DRM_ERR(EFAULT);
304	}
305
306	return 0;
307	}
308
309	int i915_mem_free(DRM_IOCTL_ARGS)
310	{
311	DRM_DEVICE;
312	drm_i915_private_t *dev_priv = dev->dev_private;
313	drm_i915_mem_free_t memfree;
314	struct mem_block block, *heap;
315
316	if (!dev_priv) {
317	DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
318	return DRM_ERR(EINVAL);
319	}
320
321	DRM_COPY_FROM_USER_IOCTL(memfree, (drm_i915_mem_free_t __user *) data,
322	sizeof(memfree));
323
324	heap = get_heap(dev_priv, memfree.region);
325	if (!heap \|\| !*heap)
326	return DRM_ERR(EFAULT);
327
328	block = find_block(*heap, memfree.region_offset);
329	if (!block)
330	return DRM_ERR(EFAULT);
331
332	if (block->filp != filp)
333	return DRM_ERR(EPERM);
334
335	mark_block(dev, block, 0);
336	free_block(block);
337	return 0;
338	}
339
340	int i915_mem_init_heap(DRM_IOCTL_ARGS)
341	{
342	DRM_DEVICE;
343	drm_i915_private_t *dev_priv = dev->dev_private;
344	drm_i915_mem_init_heap_t initheap;
345	struct mem_block **heap;
346
347	if (!dev_priv) {
348	DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
349	return DRM_ERR(EINVAL);
350	}
351
352	DRM_COPY_FROM_USER_IOCTL(initheap,
353	(drm_i915_mem_init_heap_t __user *) data,
354	sizeof(initheap));
355
356	heap = get_heap(dev_priv, initheap.region);
357	if (!heap)
358	return DRM_ERR(EFAULT);
359
360	if (*heap) {
361	DRM_ERROR("heap already initialized?");
362	return DRM_ERR(EFAULT);
363	}
364
365	return init_heap(heap, initheap.start, initheap.size);
366	}