[net-next-2.6.git] / drivers / gpu / drm / drm_mm.c

/**************************************************************************
 *
 * Copyright 2006 Tungsten Graphics, Inc., Bismarck, ND., USA.
 * 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
 * THE COPYRIGHT HOLDERS, AUTHORS 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.
 *
 *
 **************************************************************************/

/*
 * Generic simple memory manager implementation. Intended to be used as a base
 * class implementation for more advanced memory managers.
 *
 * Note that the algorithm used is quite simple and there might be substantial
 * performance gains if a smarter free list is implemented. Currently it is just an
 * unordered stack of free regions. This could easily be improved if an RB-tree
 * is used instead. At least if we expect heavy fragmentation.
 *
 * Aligned allocations can also see improvement.
 *
 * Authors:
 * Thomas Hellström <thomas-at-tungstengraphics-dot-com>
 */

#include "drmP.h"
#include "drm_mm.h"
#include <linux/slab.h>

#define MM_UNUSED_TARGET 4

unsigned long drm_mm_tail_space(struct drm_mm *mm)
{
	struct list_head *tail_node;
	struct drm_mm_node *entry;

	tail_node = mm->ml_entry.prev;
	entry = list_entry(tail_node, struct drm_mm_node, ml_entry);
	if (!entry->free)
		return 0;

	return entry->size;
}

int drm_mm_remove_space_from_tail(struct drm_mm *mm, unsigned long size)
{
	struct list_head *tail_node;
	struct drm_mm_node *entry;

	tail_node = mm->ml_entry.prev;
	entry = list_entry(tail_node, struct drm_mm_node, ml_entry);
	if (!entry->free)
		return -ENOMEM;

	if (entry->size <= size)
		return -ENOMEM;

	entry->size -= size;
	return 0;
}

static struct drm_mm_node *drm_mm_kmalloc(struct drm_mm *mm, int atomic)
{
	struct drm_mm_node *child;

	if (atomic)
		child = kmalloc(sizeof(*child), GFP_ATOMIC);
	else
		child = kmalloc(sizeof(*child), GFP_KERNEL);

	if (unlikely(child == NULL)) {
		spin_lock(&mm->unused_lock);
		if (list_empty(&mm->unused_nodes))
			child = NULL;
		else {
			child =
			    list_entry(mm->unused_nodes.next,
				       struct drm_mm_node, fl_entry);
			list_del(&child->fl_entry);
			--mm->num_unused;
		}
		spin_unlock(&mm->unused_lock);
	}
	return child;
}

int drm_mm_pre_get(struct drm_mm *mm)
{
	struct drm_mm_node *node;

	spin_lock(&mm->unused_lock);
	while (mm->num_unused < MM_UNUSED_TARGET) {
		spin_unlock(&mm->unused_lock);
		node = kmalloc(sizeof(*node), GFP_KERNEL);
		spin_lock(&mm->unused_lock);

		if (unlikely(node == NULL)) {
			int ret = (mm->num_unused < 2) ? -ENOMEM : 0;
			spin_unlock(&mm->unused_lock);
			return ret;
		}
		++mm->num_unused;
		list_add_tail(&node->fl_entry, &mm->unused_nodes);
	}
	spin_unlock(&mm->unused_lock);
	return 0;
}
EXPORT_SYMBOL(drm_mm_pre_get);

static int drm_mm_create_tail_node(struct drm_mm *mm,
				   unsigned long start,
				   unsigned long size, int atomic)
{
	struct drm_mm_node *child;

	child = drm_mm_kmalloc(mm, atomic);
	if (unlikely(child == NULL))
		return -ENOMEM;

	child->free = 1;
	child->size = size;
	child->start = start;
	child->mm = mm;

	list_add_tail(&child->ml_entry, &mm->ml_entry);
	list_add_tail(&child->fl_entry, &mm->fl_entry);

	return 0;
}

int drm_mm_add_space_to_tail(struct drm_mm *mm, unsigned long size, int atomic)
{
	struct list_head *tail_node;
	struct drm_mm_node *entry;

	tail_node = mm->ml_entry.prev;
	entry = list_entry(tail_node, struct drm_mm_node, ml_entry);
	if (!entry->free) {
		return drm_mm_create_tail_node(mm, entry->start + entry->size,
					       size, atomic);
	}
	entry->size += size;
	return 0;
}

static struct drm_mm_node *drm_mm_split_at_start(struct drm_mm_node *parent,
						 unsigned long size,
						 int atomic)
{
	struct drm_mm_node *child;

	child = drm_mm_kmalloc(parent->mm, atomic);
	if (unlikely(child == NULL))
		return NULL;

	INIT_LIST_HEAD(&child->fl_entry);

	child->free = 0;
	child->size = size;
	child->start = parent->start;
	child->mm = parent->mm;

	list_add_tail(&child->ml_entry, &parent->ml_entry);
	INIT_LIST_HEAD(&child->fl_entry);

	parent->size -= size;
	parent->start += size;
	return child;
}


struct drm_mm_node *drm_mm_get_block(struct drm_mm_node *node,
				     unsigned long size, unsigned alignment)
{

	struct drm_mm_node *align_splitoff = NULL;
	unsigned tmp = 0;

	if (alignment)
		tmp = node->start % alignment;

	if (tmp) {
		align_splitoff =
		    drm_mm_split_at_start(node, alignment - tmp, 0);
		if (unlikely(align_splitoff == NULL))
			return NULL;
	}

	if (node->size == size) {
		list_del_init(&node->fl_entry);
		node->free = 0;
	} else {
		node = drm_mm_split_at_start(node, size, 0);
	}

	if (align_splitoff)
		drm_mm_put_block(align_splitoff);

	return node;
}

EXPORT_SYMBOL(drm_mm_get_block);

struct drm_mm_node *drm_mm_get_block_atomic(struct drm_mm_node *parent,
					    unsigned long size,
					    unsigned alignment)
{

	struct drm_mm_node *align_splitoff = NULL;
	struct drm_mm_node *child;
	unsigned tmp = 0;

	if (alignment)
		tmp = parent->start % alignment;

	if (tmp) {
		align_splitoff =
		    drm_mm_split_at_start(parent, alignment - tmp, 1);
		if (unlikely(align_splitoff == NULL))
			return NULL;
	}

	if (parent->size == size) {
		list_del_init(&parent->fl_entry);
		parent->free = 0;
		return parent;
	} else {
		child = drm_mm_split_at_start(parent, size, 1);
	}

	if (align_splitoff)
		drm_mm_put_block(align_splitoff);

	return child;
}
EXPORT_SYMBOL(drm_mm_get_block_atomic);

/*
 * Put a block. Merge with the previous and / or next block if they are free.
 * Otherwise add to the free stack.
 */

void drm_mm_put_block(struct drm_mm_node *cur)
{

	struct drm_mm *mm = cur->mm;
	struct list_head *cur_head = &cur->ml_entry;
	struct list_head *root_head = &mm->ml_entry;
	struct drm_mm_node *prev_node = NULL;
	struct drm_mm_node *next_node;

	int merged = 0;

	if (cur_head->prev != root_head) {
		prev_node =
		    list_entry(cur_head->prev, struct drm_mm_node, ml_entry);
		if (prev_node->free) {
			prev_node->size += cur->size;
			merged = 1;
		}
	}
	if (cur_head->next != root_head) {
		next_node =
		    list_entry(cur_head->next, struct drm_mm_node, ml_entry);
		if (next_node->free) {
			if (merged) {
				prev_node->size += next_node->size;
				list_del(&next_node->ml_entry);
				list_del(&next_node->fl_entry);
				if (mm->num_unused < MM_UNUSED_TARGET) {
					list_add(&next_node->fl_entry,
						 &mm->unused_nodes);
					++mm->num_unused;
				} else
					kfree(next_node);
			} else {
				next_node->size += cur->size;
				next_node->start = cur->start;
				merged = 1;
			}
		}
	}
	if (!merged) {
		cur->free = 1;
		list_add(&cur->fl_entry, &mm->fl_entry);
	} else {
		list_del(&cur->ml_entry);
		if (mm->num_unused < MM_UNUSED_TARGET) {
			list_add(&cur->fl_entry, &mm->unused_nodes);
			++mm->num_unused;
		} else
			kfree(cur);
	}
}

EXPORT_SYMBOL(drm_mm_put_block);

struct drm_mm_node *drm_mm_search_free(const struct drm_mm *mm,
				       unsigned long size,
				       unsigned alignment, int best_match)
{
	struct list_head *list;
	const struct list_head *free_stack = &mm->fl_entry;
	struct drm_mm_node *entry;
	struct drm_mm_node *best;
	unsigned long best_size;
	unsigned wasted;

	best = NULL;
	best_size = ~0UL;

	list_for_each(list, free_stack) {
		entry = list_entry(list, struct drm_mm_node, fl_entry);
		wasted = 0;

		if (entry->size < size)
			continue;

		if (alignment) {
			register unsigned tmp = entry->start % alignment;
			if (tmp)
				wasted += alignment - tmp;
		}

		if (entry->size >= size + wasted) {
			if (!best_match)
				return entry;
			if (size < best_size) {
				best = entry;
				best_size = entry->size;
			}
		}
	}

	return best;
}
EXPORT_SYMBOL(drm_mm_search_free);

int drm_mm_clean(struct drm_mm * mm)
{
	struct list_head *head = &mm->ml_entry;

	return (head->next->next == head);
}
EXPORT_SYMBOL(drm_mm_clean);

int drm_mm_init(struct drm_mm * mm, unsigned long start, unsigned long size)
{
	INIT_LIST_HEAD(&mm->ml_entry);
	INIT_LIST_HEAD(&mm->fl_entry);
	INIT_LIST_HEAD(&mm->unused_nodes);
	mm->num_unused = 0;
	spin_lock_init(&mm->unused_lock);

	return drm_mm_create_tail_node(mm, start, size, 0);
}
EXPORT_SYMBOL(drm_mm_init);

void drm_mm_takedown(struct drm_mm * mm)
{
	struct list_head *bnode = mm->fl_entry.next;
	struct drm_mm_node *entry;
	struct drm_mm_node *next;

	entry = list_entry(bnode, struct drm_mm_node, fl_entry);

	if (entry->ml_entry.next != &mm->ml_entry ||
	    entry->fl_entry.next != &mm->fl_entry) {
		DRM_ERROR("Memory manager not clean. Delaying takedown\n");
		return;
	}

	list_del(&entry->fl_entry);
	list_del(&entry->ml_entry);
	kfree(entry);

	spin_lock(&mm->unused_lock);
	list_for_each_entry_safe(entry, next, &mm->unused_nodes, fl_entry) {
		list_del(&entry->fl_entry);
		kfree(entry);
		--mm->num_unused;
	}
	spin_unlock(&mm->unused_lock);

	BUG_ON(mm->num_unused != 0);
}
EXPORT_SYMBOL(drm_mm_takedown);
Commit	Line	Data
3a1bd924 TH	1	/**************************************************************************
	2	*
	3	* Copyright 2006 Tungsten Graphics, Inc., Bismarck, ND., USA.
	4	* All Rights Reserved.
	5	*
	6	* Permission is hereby granted, free of charge, to any person obtaining a
	7	* copy of this software and associated documentation files (the
	8	* "Software"), to deal in the Software without restriction, including
	9	* without limitation the rights to use, copy, modify, merge, publish,
	10	* distribute, sub license, and/or sell copies of the Software, and to
	11	* permit persons to whom the Software is furnished to do so, subject to
	12	* the following conditions:
	13	*
	14	* The above copyright notice and this permission notice (including the
	15	* next paragraph) shall be included in all copies or substantial portions
	16	* of the Software.
	17	*
	18	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	19	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	20	* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
	21	* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
	22	* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
	23	* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
	24	* USE OR OTHER DEALINGS IN THE SOFTWARE.
	25	*
	26	*
	27	**************************************************************************/
	28
	29	/*
	30	* Generic simple memory manager implementation. Intended to be used as a base
	31	* class implementation for more advanced memory managers.
	32	*
	33	* Note that the algorithm used is quite simple and there might be substantial
	34	* performance gains if a smarter free list is implemented. Currently it is just an
	35	* unordered stack of free regions. This could easily be improved if an RB-tree
	36	* is used instead. At least if we expect heavy fragmentation.
	37	*
	38	* Aligned allocations can also see improvement.
	39	*
	40	* Authors:
96de0e25	41	* Thomas Hellström <thomas-at-tungstengraphics-dot-com>
3a1bd924 TH	42	*/
	43
	44	#include "drmP.h"
249d6048	45	#include "drm_mm.h"
1d58420b TH	46	#include <linux/slab.h>
1d58420b TH	47
249d6048 JG	48	#define MM_UNUSED_TARGET 4
249d6048 JG	49
55910517	50	unsigned long drm_mm_tail_space(struct drm_mm *mm)
1d58420b TH	51	{
1d58420b TH	52	struct list_head *tail_node;
55910517	53	struct drm_mm_node *entry;
1d58420b TH	54
1d58420b TH	55	tail_node = mm->ml_entry.prev;
55910517	56	entry = list_entry(tail_node, struct drm_mm_node, ml_entry);
1d58420b TH	57	if (!entry->free)
	58	return 0;
	59
	60	return entry->size;
	61	}
	62
55910517	63	int drm_mm_remove_space_from_tail(struct drm_mm *mm, unsigned long size)
1d58420b TH	64	{
1d58420b TH	65	struct list_head *tail_node;
55910517	66	struct drm_mm_node *entry;
1d58420b TH	67
1d58420b TH	68	tail_node = mm->ml_entry.prev;
55910517	69	entry = list_entry(tail_node, struct drm_mm_node, ml_entry);
1d58420b TH	70	if (!entry->free)
	71	return -ENOMEM;
	72
	73	if (entry->size <= size)
	74	return -ENOMEM;
	75
	76	entry->size -= size;
	77	return 0;
	78	}
	79
249d6048 JG	80	static struct drm_mm_node drm_mm_kmalloc(struct drm_mm mm, int atomic)
	81	{
	82	struct drm_mm_node *child;
	83
	84	if (atomic)
	85	child = kmalloc(sizeof(*child), GFP_ATOMIC);
	86	else
	87	child = kmalloc(sizeof(*child), GFP_KERNEL);
	88
	89	if (unlikely(child == NULL)) {
	90	spin_lock(&mm->unused_lock);
	91	if (list_empty(&mm->unused_nodes))
	92	child = NULL;
	93	else {
	94	child =
	95	list_entry(mm->unused_nodes.next,
	96	struct drm_mm_node, fl_entry);
	97	list_del(&child->fl_entry);
	98	--mm->num_unused;
	99	}
	100	spin_unlock(&mm->unused_lock);
	101	}
	102	return child;
	103	}
	104
	105	int drm_mm_pre_get(struct drm_mm *mm)
	106	{
	107	struct drm_mm_node *node;
	108
	109	spin_lock(&mm->unused_lock);
	110	while (mm->num_unused < MM_UNUSED_TARGET) {
	111	spin_unlock(&mm->unused_lock);
	112	node = kmalloc(sizeof(*node), GFP_KERNEL);
	113	spin_lock(&mm->unused_lock);
	114
	115	if (unlikely(node == NULL)) {
	116	int ret = (mm->num_unused < 2) ? -ENOMEM : 0;
	117	spin_unlock(&mm->unused_lock);
	118	return ret;
	119	}
	120	++mm->num_unused;
	121	list_add_tail(&node->fl_entry, &mm->unused_nodes);
	122	}
	123	spin_unlock(&mm->unused_lock);
	124	return 0;
	125	}
	126	EXPORT_SYMBOL(drm_mm_pre_get);
1d58420b	127
55910517	128	static int drm_mm_create_tail_node(struct drm_mm *mm,
249d6048 JG	129	unsigned long start,
249d6048 JG	130	unsigned long size, int atomic)
1d58420b	131	{
55910517	132	struct drm_mm_node *child;
1d58420b	133
249d6048 JG	134	child = drm_mm_kmalloc(mm, atomic);
249d6048 JG	135	if (unlikely(child == NULL))
1d58420b TH	136	return -ENOMEM;
	137
	138	child->free = 1;
	139	child->size = size;
	140	child->start = start;
	141	child->mm = mm;
	142
	143	list_add_tail(&child->ml_entry, &mm->ml_entry);
	144	list_add_tail(&child->fl_entry, &mm->fl_entry);
	145
	146	return 0;
	147	}
	148
249d6048	149	int drm_mm_add_space_to_tail(struct drm_mm *mm, unsigned long size, int atomic)
1d58420b TH	150	{
1d58420b TH	151	struct list_head *tail_node;
55910517	152	struct drm_mm_node *entry;
1d58420b TH	153
1d58420b TH	154	tail_node = mm->ml_entry.prev;
55910517	155	entry = list_entry(tail_node, struct drm_mm_node, ml_entry);
1d58420b	156	if (!entry->free) {
249d6048 JG	157	return drm_mm_create_tail_node(mm, entry->start + entry->size,
249d6048 JG	158	size, atomic);
1d58420b TH	159	}
	160	entry->size += size;
	161	return 0;
	162	}
	163
55910517	164	static struct drm_mm_node drm_mm_split_at_start(struct drm_mm_node parent,
249d6048 JG	165	unsigned long size,
249d6048 JG	166	int atomic)
1d58420b	167	{
55910517	168	struct drm_mm_node *child;
1d58420b	169
249d6048 JG	170	child = drm_mm_kmalloc(parent->mm, atomic);
249d6048 JG	171	if (unlikely(child == NULL))
1d58420b TH	172	return NULL;
	173
	174	INIT_LIST_HEAD(&child->fl_entry);
	175
	176	child->free = 0;
	177	child->size = size;
	178	child->start = parent->start;
	179	child->mm = parent->mm;
	180
	181	list_add_tail(&child->ml_entry, &parent->ml_entry);
	182	INIT_LIST_HEAD(&child->fl_entry);
	183
	184	parent->size -= size;
	185	parent->start += size;
	186	return child;
	187	}
	188
	189
3a1bd924	190
e6c03c5b CW	191	struct drm_mm_node drm_mm_get_block(struct drm_mm_node node,
e6c03c5b CW	192	unsigned long size, unsigned alignment)
3a1bd924 TH	193	{
3a1bd924 TH	194
55910517	195	struct drm_mm_node *align_splitoff = NULL;
1d58420b	196	unsigned tmp = 0;
3a1bd924 TH	197
3a1bd924 TH	198	if (alignment)
e6c03c5b	199	tmp = node->start % alignment;
1d58420b TH	200
1d58420b TH	201	if (tmp) {
249d6048	202	align_splitoff =
e6c03c5b	203	drm_mm_split_at_start(node, alignment - tmp, 0);
249d6048	204	if (unlikely(align_splitoff == NULL))
1d58420b TH	205	return NULL;
1d58420b TH	206	}
3a1bd924	207
e6c03c5b CW	208	if (node->size == size) {
	209	list_del_init(&node->fl_entry);
	210	node->free = 0;
3a1bd924	211	} else {
e6c03c5b	212	node = drm_mm_split_at_start(node, size, 0);
1d58420b	213	}
3a1bd924	214
1d58420b TH	215	if (align_splitoff)
1d58420b TH	216	drm_mm_put_block(align_splitoff);
3a1bd924	217
e6c03c5b	218	return node;
3a1bd924	219	}
249d6048	220
673a394b	221	EXPORT_SYMBOL(drm_mm_get_block);
3a1bd924	222
249d6048 JG	223	struct drm_mm_node drm_mm_get_block_atomic(struct drm_mm_node parent,
	224	unsigned long size,
	225	unsigned alignment)
	226	{
	227
	228	struct drm_mm_node *align_splitoff = NULL;
	229	struct drm_mm_node *child;
	230	unsigned tmp = 0;
	231
	232	if (alignment)
	233	tmp = parent->start % alignment;
	234
	235	if (tmp) {
	236	align_splitoff =
	237	drm_mm_split_at_start(parent, alignment - tmp, 1);
	238	if (unlikely(align_splitoff == NULL))
	239	return NULL;
	240	}
	241
	242	if (parent->size == size) {
	243	list_del_init(&parent->fl_entry);
	244	parent->free = 0;
	245	return parent;
	246	} else {
	247	child = drm_mm_split_at_start(parent, size, 1);
	248	}
	249
	250	if (align_splitoff)
	251	drm_mm_put_block(align_splitoff);
	252
	253	return child;
	254	}
	255	EXPORT_SYMBOL(drm_mm_get_block_atomic);
	256
3a1bd924 TH	257	/*
	258	* Put a block. Merge with the previous and / or next block if they are free.
	259	* Otherwise add to the free stack.
	260	*/
	261
249d6048	262	void drm_mm_put_block(struct drm_mm_node *cur)
3a1bd924 TH	263	{
3a1bd924 TH	264
55910517	265	struct drm_mm *mm = cur->mm;
3a1bd924	266	struct list_head *cur_head = &cur->ml_entry;
1d58420b	267	struct list_head *root_head = &mm->ml_entry;
55910517 DA	268	struct drm_mm_node *prev_node = NULL;
55910517 DA	269	struct drm_mm_node *next_node;
3a1bd924	270
a1d0fcf5	271	int merged = 0;
3a1bd924 TH	272
3a1bd924 TH	273	if (cur_head->prev != root_head) {
249d6048 JG	274	prev_node =
249d6048 JG	275	list_entry(cur_head->prev, struct drm_mm_node, ml_entry);
3a1bd924 TH	276	if (prev_node->free) {
3a1bd924 TH	277	prev_node->size += cur->size;
a1d0fcf5	278	merged = 1;
3a1bd924 TH	279	}
	280	}
	281	if (cur_head->next != root_head) {
249d6048 JG	282	next_node =
249d6048 JG	283	list_entry(cur_head->next, struct drm_mm_node, ml_entry);
3a1bd924 TH	284	if (next_node->free) {
	285	if (merged) {
	286	prev_node->size += next_node->size;
	287	list_del(&next_node->ml_entry);
	288	list_del(&next_node->fl_entry);
249d6048 JG	289	if (mm->num_unused < MM_UNUSED_TARGET) {
	290	list_add(&next_node->fl_entry,
	291	&mm->unused_nodes);
	292	++mm->num_unused;
	293	} else
	294	kfree(next_node);
3a1bd924 TH	295	} else {
	296	next_node->size += cur->size;
	297	next_node->start = cur->start;
a1d0fcf5	298	merged = 1;
3a1bd924 TH	299	}
	300	}
	301	}
	302	if (!merged) {
a1d0fcf5	303	cur->free = 1;
1d58420b	304	list_add(&cur->fl_entry, &mm->fl_entry);
3a1bd924 TH	305	} else {
3a1bd924 TH	306	list_del(&cur->ml_entry);
249d6048 JG	307	if (mm->num_unused < MM_UNUSED_TARGET) {
	308	list_add(&cur->fl_entry, &mm->unused_nodes);
	309	++mm->num_unused;
	310	} else
	311	kfree(cur);
3a1bd924 TH	312	}
3a1bd924 TH	313	}
249d6048	314
673a394b	315	EXPORT_SYMBOL(drm_mm_put_block);
3a1bd924	316
249d6048 JG	317	struct drm_mm_node drm_mm_search_free(const struct drm_mm mm,
	318	unsigned long size,
	319	unsigned alignment, int best_match)
3a1bd924 TH	320	{
3a1bd924 TH	321	struct list_head *list;
1d58420b	322	const struct list_head *free_stack = &mm->fl_entry;
55910517 DA	323	struct drm_mm_node *entry;
55910517 DA	324	struct drm_mm_node *best;
3a1bd924	325	unsigned long best_size;
1d58420b	326	unsigned wasted;
3a1bd924 TH	327
	328	best = NULL;
	329	best_size = ~0UL;
	330
3a1bd924	331	list_for_each(list, free_stack) {
55910517	332	entry = list_entry(list, struct drm_mm_node, fl_entry);
1d58420b TH	333	wasted = 0;
	334
	335	if (entry->size < size)
	336	continue;
	337
	338	if (alignment) {
	339	register unsigned tmp = entry->start % alignment;
	340	if (tmp)
	341	wasted += alignment - tmp;
	342	}
	343
1d58420b	344	if (entry->size >= size + wasted) {
3a1bd924 TH	345	if (!best_match)
	346	return entry;
	347	if (size < best_size) {
	348	best = entry;
	349	best_size = entry->size;
	350	}
	351	}
	352	}
	353
	354	return best;
	355	}
249d6048	356	EXPORT_SYMBOL(drm_mm_search_free);
3a1bd924	357
55910517	358	int drm_mm_clean(struct drm_mm * mm)
3a1bd924	359	{
1d58420b	360	struct list_head *head = &mm->ml_entry;
3a1bd924	361
1d58420b TH	362	return (head->next->next == head);
1d58420b TH	363	}
249d6048	364	EXPORT_SYMBOL(drm_mm_clean);
3a1bd924	365
55910517	366	int drm_mm_init(struct drm_mm * mm, unsigned long start, unsigned long size)
1d58420b TH	367	{
	368	INIT_LIST_HEAD(&mm->ml_entry);
	369	INIT_LIST_HEAD(&mm->fl_entry);
249d6048 JG	370	INIT_LIST_HEAD(&mm->unused_nodes);
	371	mm->num_unused = 0;
	372	spin_lock_init(&mm->unused_lock);
3a1bd924	373
249d6048	374	return drm_mm_create_tail_node(mm, start, size, 0);
3a1bd924	375	}
673a394b	376	EXPORT_SYMBOL(drm_mm_init);
3a1bd924	377
55910517	378	void drm_mm_takedown(struct drm_mm * mm)
3a1bd924	379	{
1d58420b	380	struct list_head *bnode = mm->fl_entry.next;
55910517	381	struct drm_mm_node *entry;
249d6048	382	struct drm_mm_node *next;
3a1bd924	383
55910517	384	entry = list_entry(bnode, struct drm_mm_node, fl_entry);
3a1bd924	385
1d58420b TH	386	if (entry->ml_entry.next != &mm->ml_entry \|\|
1d58420b TH	387	entry->fl_entry.next != &mm->fl_entry) {
3a1bd924 TH	388	DRM_ERROR("Memory manager not clean. Delaying takedown\n");
	389	return;
	390	}
	391
	392	list_del(&entry->fl_entry);
	393	list_del(&entry->ml_entry);
249d6048 JG	394	kfree(entry);
	395
	396	spin_lock(&mm->unused_lock);
	397	list_for_each_entry_safe(entry, next, &mm->unused_nodes, fl_entry) {
	398	list_del(&entry->fl_entry);
	399	kfree(entry);
	400	--mm->num_unused;
	401	}
	402	spin_unlock(&mm->unused_lock);
3a1bd924	403
249d6048	404	BUG_ON(mm->num_unused != 0);
3a1bd924	405	}
f453ba04	406	EXPORT_SYMBOL(drm_mm_takedown);