1 /* i915_mem.c -- Simple agp/fb memory manager for i915 -*- linux-c -*-
3 /**************************************************************************
5 * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
8 **************************************************************************/
15 /* This memory manager is integrated into the global/local lru
16 * mechanisms used by the clients. Specifically, it operates by
17 * setting the 'in_use' fields of the global LRU to indicate whether
18 * this region is privately allocated to a client.
20 * This does require the client to actually respect that field.
22 * Currently no effort is made to allocate 'private' memory in any
23 * clever way - the LRU information isn't used to determine which
24 * block to allocate, and the ring is drained prior to allocations --
25 * in other words allocation is expensive.
27 static void mark_block(drm_device_t * dev, struct mem_block *p, int in_use)
29 drm_i915_private_t *dev_priv = dev->dev_private;
30 drm_i915_sarea_t *sarea_priv = dev_priv->sarea_priv;
31 drm_tex_region_t *list;
38 shift = dev_priv->tex_lru_log_granularity;
39 nr = I915_NR_TEX_REGIONS;
41 start = p->start >> shift;
42 end = (p->start + p->size - 1) >> shift;
44 age = ++sarea_priv->texAge;
45 list = sarea_priv->texList;
47 /* Mark the regions with the new flag and update their age. Move
48 * them to head of list to preserve LRU semantics.
50 for (i = start; i <= end; i++) {
51 list[i].in_use = in_use;
54 /* remove_from_list(i)
56 list[(unsigned)list[i].next].prev = list[i].prev;
57 list[(unsigned)list[i].prev].next = list[i].next;
59 /* insert_at_head(list, i)
62 list[i].next = list[nr].next;
63 list[(unsigned)list[nr].next].prev = i;
68 /* Very simple allocator for agp memory, working on a static range
69 * already mapped into each client's address space.
72 static struct mem_block *split_block(struct mem_block *p, int start, int size,
75 /* Maybe cut off the start of an existing block */
76 if (start > p->start) {
77 struct mem_block *newblock = drm_alloc(sizeof(*newblock), DRM_MEM_BUFLISTS);
80 newblock->start = start;
81 newblock->size = p->size - (start - p->start);
82 newblock->filp = NULL;
83 newblock->next = p->next;
85 p->next->prev = newblock;
87 p->size -= newblock->size;
91 /* Maybe cut off the end of an existing block */
93 struct mem_block *newblock = drm_alloc(sizeof(*newblock), DRM_MEM_BUFLISTS);
96 newblock->start = start + size;
97 newblock->size = p->size - size;
98 newblock->filp = NULL;
99 newblock->next = p->next;
101 p->next->prev = newblock;
107 /* Our block is in the middle */
112 static struct mem_block *alloc_block(struct mem_block *heap, int size,
113 int align2, DRMFILE filp)
116 int mask = (1 << align2) - 1;
118 for (p = heap->next; p != heap; p = p->next) {
119 int start = (p->start + mask) & ~mask;
120 if (p->filp == NULL && start + size <= p->start + p->size)
121 return split_block(p, start, size, filp);
127 static struct mem_block *find_block(struct mem_block *heap, int start)
131 for (p = heap->next; p != heap; p = p->next)
132 if (p->start == start)
138 static void free_block(struct mem_block *p)
142 /* Assumes a single contiguous range. Needs a special filp in
143 * 'heap' to stop it being subsumed.
145 if (p->next->filp == NULL) {
146 struct mem_block *q = p->next;
150 drm_free(q, sizeof(*q), DRM_MEM_BUFLISTS);
153 if (p->prev->filp == NULL) {
154 struct mem_block *q = p->prev;
158 drm_free(p, sizeof(*q), DRM_MEM_BUFLISTS);
162 /* Initialize. How to check for an uninitialized heap?
164 static int init_heap(struct mem_block **heap, int start, int size)
166 struct mem_block *blocks = drm_alloc(sizeof(*blocks), DRM_MEM_BUFLISTS);
171 *heap = drm_alloc(sizeof(**heap), DRM_MEM_BUFLISTS);
173 drm_free(blocks, sizeof(*blocks), DRM_MEM_BUFLISTS);
177 blocks->start = start;
180 blocks->next = blocks->prev = *heap;
182 memset(*heap, 0, sizeof(**heap));
183 (*heap)->filp = (DRMFILE) - 1;
184 (*heap)->next = (*heap)->prev = blocks;
188 /* Free all blocks associated with the releasing file.
190 void i915_mem_release(drm_device_t * dev, DRMFILE filp, struct mem_block *heap)
194 if (!heap || !heap->next)
197 for (p = heap->next; p != heap; p = p->next) {
198 if (p->filp == filp) {
200 mark_block(dev, p, 0);
204 /* Assumes a single contiguous range. Needs a special filp in
205 * 'heap' to stop it being subsumed.
207 for (p = heap->next; p != heap; p = p->next) {
208 while (p->filp == NULL && p->next->filp == NULL) {
209 struct mem_block *q = p->next;
213 drm_free(q, sizeof(*q), DRM_MEM_BUFLISTS);
220 void i915_mem_takedown(struct mem_block **heap)
227 for (p = (*heap)->next; p != *heap;) {
228 struct mem_block *q = p;
230 drm_free(q, sizeof(*q), DRM_MEM_BUFLISTS);
233 drm_free(*heap, sizeof(**heap), DRM_MEM_BUFLISTS);
237 static struct mem_block **get_heap(drm_i915_private_t * dev_priv, int region)
240 case I915_MEM_REGION_AGP:
241 return &dev_priv->agp_heap;
249 int i915_mem_alloc(DRM_IOCTL_ARGS)
252 drm_i915_private_t *dev_priv = dev->dev_private;
253 drm_i915_mem_alloc_t alloc;
254 struct mem_block *block, **heap;
257 DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
258 return DRM_ERR(EINVAL);
261 DRM_COPY_FROM_USER_IOCTL(alloc, (drm_i915_mem_alloc_t __user *) data,
264 heap = get_heap(dev_priv, alloc.region);
266 return DRM_ERR(EFAULT);
268 /* Make things easier on ourselves: all allocations at least
271 if (alloc.alignment < 12)
272 alloc.alignment = 12;
274 block = alloc_block(*heap, alloc.size, alloc.alignment, filp);
277 return DRM_ERR(ENOMEM);
279 mark_block(dev, block, 1);
281 if (DRM_COPY_TO_USER(alloc.region_offset, &block->start, sizeof(int))) {
282 DRM_ERROR("copy_to_user\n");
283 return DRM_ERR(EFAULT);
289 int i915_mem_free(DRM_IOCTL_ARGS)
292 drm_i915_private_t *dev_priv = dev->dev_private;
293 drm_i915_mem_free_t memfree;
294 struct mem_block *block, **heap;
297 DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
298 return DRM_ERR(EINVAL);
301 DRM_COPY_FROM_USER_IOCTL(memfree, (drm_i915_mem_free_t __user *) data,
304 heap = get_heap(dev_priv, memfree.region);
306 return DRM_ERR(EFAULT);
308 block = find_block(*heap, memfree.region_offset);
310 return DRM_ERR(EFAULT);
312 if (block->filp != filp)
313 return DRM_ERR(EPERM);
315 mark_block(dev, block, 0);
320 int i915_mem_init_heap(DRM_IOCTL_ARGS)
323 drm_i915_private_t *dev_priv = dev->dev_private;
324 drm_i915_mem_init_heap_t initheap;
325 struct mem_block **heap;
328 DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
329 return DRM_ERR(EINVAL);
332 DRM_COPY_FROM_USER_IOCTL(initheap,
333 (drm_i915_mem_init_heap_t __user *) data,
336 heap = get_heap(dev_priv, initheap.region);
338 return DRM_ERR(EFAULT);
341 DRM_ERROR("heap already initialized?");
342 return DRM_ERR(EFAULT);
345 return init_heap(heap, initheap.start, initheap.size);