1/* radeon_mem.c -- Simple GART/fb memory manager for radeon -*- linux-c -*- */
  2/*
  3 * Copyright (C) The Weather Channel, Inc.  2002.  All Rights Reserved.
  4 *
  5 * The Weather Channel (TM) funded Tungsten Graphics to develop the
  6 * initial release of the Radeon 8500 driver under the XFree86 license.
  7 * This notice must be preserved.
  8 *
  9 * Permission is hereby granted, free of charge, to any person obtaining a
 10 * copy of this software and associated documentation files (the "Software"),
 11 * to deal in the Software without restriction, including without limitation
 12 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 13 * and/or sell copies of the Software, and to permit persons to whom the
 14 * Software is furnished to do so, subject to the following conditions:
 15 *
 16 * The above copyright notice and this permission notice (including the next
 17 * paragraph) shall be included in all copies or substantial portions of the
 18 * Software.
 19 *
 20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 23 * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 24 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 25 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 26 * DEALINGS IN THE SOFTWARE.
 27 *
 28 * Authors:
 29 *    Keith Whitwell <keith@tungstengraphics.com>
 30 */
 31
 32#include "drmP.h"
 33#include "drm.h"
 34#include "radeon_drm.h"
 35#include "radeon_drv.h"
 36
 37/* Very simple allocator for GART memory, working on a static range
 38 * already mapped into each client's address space.
 39 */
 40
 41static struct mem_block *split_block(struct mem_block *p, int start, int size,
 42				     struct drm_file *file_priv)
 43{
 44	/* Maybe cut off the start of an existing block */
 45	if (start > p->start) {
 46		struct mem_block *newblock = kmalloc(sizeof(*newblock),
 47						     GFP_KERNEL);
 48		if (!newblock)
 49			goto out;
 50		newblock->start = start;
 51		newblock->size = p->size - (start - p->start);
 52		newblock->file_priv = NULL;
 53		newblock->next = p->next;
 54		newblock->prev = p;
 55		p->next->prev = newblock;
 56		p->next = newblock;
 57		p->size -= newblock->size;
 58		p = newblock;
 59	}
 60
 61	/* Maybe cut off the end of an existing block */
 62	if (size < p->size) {
 63		struct mem_block *newblock = kmalloc(sizeof(*newblock),
 64						     GFP_KERNEL);
 65		if (!newblock)
 66			goto out;
 67		newblock->start = start + size;
 68		newblock->size = p->size - size;
 69		newblock->file_priv = NULL;
 70		newblock->next = p->next;
 71		newblock->prev = p;
 72		p->next->prev = newblock;
 73		p->next = newblock;
 74		p->size = size;
 75	}
 76
 77      out:
 78	/* Our block is in the middle */
 79	p->file_priv = file_priv;
 80	return p;
 81}
 82
 83static struct mem_block *alloc_block(struct mem_block *heap, int size,
 84				     int align2, struct drm_file *file_priv)
 85{
 86	struct mem_block *p;
 87	int mask = (1 << align2) - 1;
 88
 89	list_for_each(p, heap) {
 90		int start = (p->start + mask) & ~mask;
 91		if (p->file_priv == NULL && start + size <= p->start + p->size)
 92			return split_block(p, start, size, file_priv);
 93	}
 94
 95	return NULL;
 96}
 97
 98static struct mem_block *find_block(struct mem_block *heap, int start)
 99{
100	struct mem_block *p;
101
102	list_for_each(p, heap)
103	    if (p->start == start)
104		return p;
105
106	return NULL;
107}
108
109static void free_block(struct mem_block *p)
110{
111	p->file_priv = NULL;
112
113	/* Assumes a single contiguous range.  Needs a special file_priv in
114	 * 'heap' to stop it being subsumed.
115	 */
116	if (p->next->file_priv == NULL) {
117		struct mem_block *q = p->next;
118		p->size += q->size;
119		p->next = q->next;
120		p->next->prev = p;
121		kfree(q);
122	}
123
124	if (p->prev->file_priv == NULL) {
125		struct mem_block *q = p->prev;
126		q->size += p->size;
127		q->next = p->next;
128		q->next->prev = q;
129		kfree(p);
130	}
131}
132
133/* Initialize.  How to check for an uninitialized heap?
134 */
135static int init_heap(struct mem_block **heap, int start, int size)
136{
137	struct mem_block *blocks = kmalloc(sizeof(*blocks), GFP_KERNEL);
138
139	if (!blocks)
140		return -ENOMEM;
141
142	*heap = kzalloc(sizeof(**heap), GFP_KERNEL);
143	if (!*heap) {
144		kfree(blocks);
145		return -ENOMEM;
146	}
147
148	blocks->start = start;
149	blocks->size = size;
150	blocks->file_priv = NULL;
151	blocks->next = blocks->prev = *heap;
152
153	(*heap)->file_priv = (struct drm_file *) - 1;
154	(*heap)->next = (*heap)->prev = blocks;
155	return 0;
156}
157
158/* Free all blocks associated with the releasing file.
159 */
160void radeon_mem_release(struct drm_file *file_priv, struct mem_block *heap)
161{
162	struct mem_block *p;
163
164	if (!heap || !heap->next)
165		return;
166
167	list_for_each(p, heap) {
168		if (p->file_priv == file_priv)
169			p->file_priv = NULL;
170	}
171
172	/* Assumes a single contiguous range.  Needs a special file_priv in
173	 * 'heap' to stop it being subsumed.
174	 */
175	list_for_each(p, heap) {
176		while (p->file_priv == NULL && p->next->file_priv == NULL) {
177			struct mem_block *q = p->next;
178			p->size += q->size;
179			p->next = q->next;
180			p->next->prev = p;
181			kfree(q);
182		}
183	}
184}
185
186/* Shutdown.
187 */
188void radeon_mem_takedown(struct mem_block **heap)
189{
190	struct mem_block *p;
191
192	if (!*heap)
193		return;
194
195	for (p = (*heap)->next; p != *heap;) {
196		struct mem_block *q = p;
197		p = p->next;
198		kfree(q);
199	}
200
201	kfree(*heap);
202	*heap = NULL;
203}
204
205/* IOCTL HANDLERS */
206
207static struct mem_block **get_heap(drm_radeon_private_t * dev_priv, int region)
208{
209	switch (region) {
210	case RADEON_MEM_REGION_GART:
211		return &dev_priv->gart_heap;
212	case RADEON_MEM_REGION_FB:
213		return &dev_priv->fb_heap;
214	default:
215		return NULL;
216	}
217}
218
219int radeon_mem_alloc(struct drm_device *dev, void *data, struct drm_file *file_priv)
220{
221	drm_radeon_private_t *dev_priv = dev->dev_private;
222	drm_radeon_mem_alloc_t *alloc = data;
223	struct mem_block *block, **heap;
224
225	if (!dev_priv) {
226		DRM_ERROR("called with no initialization\n");
227		return -EINVAL;
228	}
229
230	heap = get_heap(dev_priv, alloc->region);
231	if (!heap || !*heap)
232		return -EFAULT;
233
234	/* Make things easier on ourselves: all allocations at least
235	 * 4k aligned.
236	 */
237	if (alloc->alignment < 12)
238		alloc->alignment = 12;
239
240	block = alloc_block(*heap, alloc->size, alloc->alignment, file_priv);
241
242	if (!block)
243		return -ENOMEM;
244
245	if (DRM_COPY_TO_USER(alloc->region_offset, &block->start,
246			     sizeof(int))) {
247		DRM_ERROR("copy_to_user\n");
248		return -EFAULT;
249	}
250
251	return 0;
252}
253
254int radeon_mem_free(struct drm_device *dev, void *data, struct drm_file *file_priv)
255{
256	drm_radeon_private_t *dev_priv = dev->dev_private;
257	drm_radeon_mem_free_t *memfree = data;
258	struct mem_block *block, **heap;
259
260	if (!dev_priv) {
261		DRM_ERROR("called with no initialization\n");
262		return -EINVAL;
263	}
264
265	heap = get_heap(dev_priv, memfree->region);
266	if (!heap || !*heap)
267		return -EFAULT;
268
269	block = find_block(*heap, memfree->region_offset);
270	if (!block)
271		return -EFAULT;
272
273	if (block->file_priv != file_priv)
274		return -EPERM;
275
276	free_block(block);
277	return 0;
278}
279
280int radeon_mem_init_heap(struct drm_device *dev, void *data, struct drm_file *file_priv)
281{
282	drm_radeon_private_t *dev_priv = dev->dev_private;
283	drm_radeon_mem_init_heap_t *initheap = data;
284	struct mem_block **heap;
285
286	if (!dev_priv) {
287		DRM_ERROR("called with no initialization\n");
288		return -EINVAL;
289	}
290
291	heap = get_heap(dev_priv, initheap->region);
292	if (!heap)
293		return -EFAULT;
294
295	if (*heap) {
296		DRM_ERROR("heap already initialized?");
297		return -EFAULT;
298	}
299
300	return init_heap(heap, initheap->start, initheap->size);
301}