| /* |
| * Copyright 2007 Nouveau Project |
| * |
| * 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, sublicense, |
| * 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 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 NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS 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. |
| */ |
| |
| #ifndef __NOUVEAU_HEAP_H__ |
| #define __NOUVEAU_HEAP_H__ |
| |
| /* This datastructure represents a memory allocation heap. Fundamentally, this |
| * is a doubly-linked list with a few properties, and a usage convention. |
| * |
| * On initial allocation, there is a single node with the full size that's |
| * marked as not in-use. As allocations are made, blocks are taken off the end |
| * of that first node, and inserted right after it. If the first node doesn't |
| * have enough free space, we look for free space down in the rest of the |
| * list. This can happen if an allocation is made and then freed. |
| * |
| * The first node will remain with in_use == 0 even if the whole heap is |
| * exhausted. Another invariant is that there will never be two sequential |
| * in_use == 0 nodes. If a node is freed and it has one (or both) adjacent |
| * free nodes, they are merged into one, and the relevant heap entries are |
| * freed. |
| * |
| * The pattern to free the whole heap is to start with the first node and then |
| * just free the "next" node, until there is no next node. This should assure |
| * that at the end the first (and only) node is not in use and contains the |
| * full size of the heap. |
| */ |
| struct nouveau_heap { |
| struct nouveau_heap *prev; |
| struct nouveau_heap *next; |
| |
| void *priv; |
| |
| unsigned start; |
| unsigned size; |
| |
| int in_use; |
| }; |
| |
| int |
| nouveau_heap_init(struct nouveau_heap **heap, unsigned start, |
| unsigned size); |
| |
| void |
| nouveau_heap_destroy(struct nouveau_heap **heap); |
| |
| int |
| nouveau_heap_alloc(struct nouveau_heap *heap, unsigned size, void *priv, |
| struct nouveau_heap **); |
| |
| void |
| nouveau_heap_free(struct nouveau_heap **); |
| |
| #endif |