1/**************************************************************************
2 *
3 * Copyright 2006-2008 Tungsten Graphics, Inc., Cedar Park, TX. 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 * Authors:
30 * Thomas Hellstrom <thomas-at-tungstengraphics-dot-com>
31 */
32
33#ifndef _DRM_MM_H_
34#define _DRM_MM_H_
35
36/*
37 * Generic range manager structs
38 */
39#include <linux/bug.h>
40#include <linux/kernel.h>
41#include <linux/list.h>
42#include <linux/spinlock.h>
43#ifdef CONFIG_DEBUG_FS
44#include <linux/seq_file.h>
45#endif
46
47enum drm_mm_search_flags {
48	DRM_MM_SEARCH_DEFAULT =		0,
49	DRM_MM_SEARCH_BEST =		1 << 0,
50	DRM_MM_SEARCH_BELOW =		1 << 1,
51};
52
53enum drm_mm_allocator_flags {
54	DRM_MM_CREATE_DEFAULT =		0,
55	DRM_MM_CREATE_TOP =		1 << 0,
56};
57
58#define DRM_MM_BOTTOMUP DRM_MM_SEARCH_DEFAULT, DRM_MM_CREATE_DEFAULT
59#define DRM_MM_TOPDOWN DRM_MM_SEARCH_BELOW, DRM_MM_CREATE_TOP
60
61struct drm_mm_node {
62	struct list_head node_list;
63	struct list_head hole_stack;
64	unsigned hole_follows : 1;
65	unsigned scanned_block : 1;
66	unsigned scanned_prev_free : 1;
67	unsigned scanned_next_free : 1;
68	unsigned scanned_preceeds_hole : 1;
69	unsigned allocated : 1;
70	unsigned long color;
71	u64 start;
72	u64 size;
73	struct drm_mm *mm;
74};
75
76struct drm_mm {
77	/* List of all memory nodes that immediately precede a free hole. */
78	struct list_head hole_stack;
79	/* head_node.node_list is the list of all memory nodes, ordered
80	 * according to the (increasing) start address of the memory node. */
81	struct drm_mm_node head_node;
82	unsigned int scan_check_range : 1;
83	unsigned scan_alignment;
84	unsigned long scan_color;
85	u64 scan_size;
86	u64 scan_hit_start;
87	u64 scan_hit_end;
88	unsigned scanned_blocks;
89	u64 scan_start;
90	u64 scan_end;
91	struct drm_mm_node *prev_scanned_node;
92
93	void (*color_adjust)(struct drm_mm_node *node, unsigned long color,
94			     u64 *start, u64 *end);
95};
96
97/**
98 * drm_mm_node_allocated - checks whether a node is allocated
99 * @node: drm_mm_node to check
100 *
101 * Drivers should use this helpers for proper encapusulation of drm_mm
102 * internals.
103 *
104 * Returns:
105 * True if the @node is allocated.
106 */
107static inline bool drm_mm_node_allocated(struct drm_mm_node *node)
108{
109	return node->allocated;
110}
111
112/**
113 * drm_mm_initialized - checks whether an allocator is initialized
114 * @mm: drm_mm to check
115 *
116 * Drivers should use this helpers for proper encapusulation of drm_mm
117 * internals.
118 *
119 * Returns:
120 * True if the @mm is initialized.
121 */
122static inline bool drm_mm_initialized(struct drm_mm *mm)
123{
124	return mm->hole_stack.next;
125}
126
127static inline u64 __drm_mm_hole_node_start(struct drm_mm_node *hole_node)
128{
129	return hole_node->start + hole_node->size;
130}
131
132/**
133 * drm_mm_hole_node_start - computes the start of the hole following @node
134 * @hole_node: drm_mm_node which implicitly tracks the following hole
135 *
136 * This is useful for driver-sepific debug dumpers. Otherwise drivers should not
137 * inspect holes themselves. Drivers must check first whether a hole indeed
138 * follows by looking at node->hole_follows.
139 *
140 * Returns:
141 * Start of the subsequent hole.
142 */
143static inline u64 drm_mm_hole_node_start(struct drm_mm_node *hole_node)
144{
145	BUG_ON(!hole_node->hole_follows);
146	return __drm_mm_hole_node_start(hole_node);
147}
148
149static inline u64 __drm_mm_hole_node_end(struct drm_mm_node *hole_node)
150{
151	return list_entry(hole_node->node_list.next,
152			  struct drm_mm_node, node_list)->start;
153}
154
155/**
156 * drm_mm_hole_node_end - computes the end of the hole following @node
157 * @hole_node: drm_mm_node which implicitly tracks the following hole
158 *
159 * This is useful for driver-sepific debug dumpers. Otherwise drivers should not
160 * inspect holes themselves. Drivers must check first whether a hole indeed
161 * follows by looking at node->hole_follows.
162 *
163 * Returns:
164 * End of the subsequent hole.
165 */
166static inline u64 drm_mm_hole_node_end(struct drm_mm_node *hole_node)
167{
168	return __drm_mm_hole_node_end(hole_node);
169}
170
171/**
172 * drm_mm_for_each_node - iterator to walk over all allocated nodes
173 * @entry: drm_mm_node structure to assign to in each iteration step
174 * @mm: drm_mm allocator to walk
175 *
176 * This iterator walks over all nodes in the range allocator. It is implemented
177 * with list_for_each, so not save against removal of elements.
178 */
179#define drm_mm_for_each_node(entry, mm) list_for_each_entry(entry, \
180						&(mm)->head_node.node_list, \
181						node_list)
182
183/**
184 * drm_mm_for_each_hole - iterator to walk over all holes
185 * @entry: drm_mm_node used internally to track progress
186 * @mm: drm_mm allocator to walk
187 * @hole_start: ulong variable to assign the hole start to on each iteration
188 * @hole_end: ulong variable to assign the hole end to on each iteration
189 *
190 * This iterator walks over all holes in the range allocator. It is implemented
191 * with list_for_each, so not save against removal of elements. @entry is used
192 * internally and will not reflect a real drm_mm_node for the very first hole.
193 * Hence users of this iterator may not access it.
194 *
195 * Implementation Note:
196 * We need to inline list_for_each_entry in order to be able to set hole_start
197 * and hole_end on each iteration while keeping the macro sane.
198 *
199 * The __drm_mm_for_each_hole version is similar, but with added support for
200 * going backwards.
201 */
202#define drm_mm_for_each_hole(entry, mm, hole_start, hole_end) \
203	for (entry = list_entry((mm)->hole_stack.next, struct drm_mm_node, hole_stack); \
204	     &entry->hole_stack != &(mm)->hole_stack ? \
205	     hole_start = drm_mm_hole_node_start(entry), \
206	     hole_end = drm_mm_hole_node_end(entry), \
207	     1 : 0; \
208	     entry = list_entry(entry->hole_stack.next, struct drm_mm_node, hole_stack))
209
210#define __drm_mm_for_each_hole(entry, mm, hole_start, hole_end, backwards) \
211	for (entry = list_entry((backwards) ? (mm)->hole_stack.prev : (mm)->hole_stack.next, struct drm_mm_node, hole_stack); \
212	     &entry->hole_stack != &(mm)->hole_stack ? \
213	     hole_start = drm_mm_hole_node_start(entry), \
214	     hole_end = drm_mm_hole_node_end(entry), \
215	     1 : 0; \
216	     entry = list_entry((backwards) ? entry->hole_stack.prev : entry->hole_stack.next, struct drm_mm_node, hole_stack))
217
218/*
219 * Basic range manager support (drm_mm.c)
220 */
221int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node);
222
223int drm_mm_insert_node_generic(struct drm_mm *mm,
224			       struct drm_mm_node *node,
225			       u64 size,
226			       unsigned alignment,
227			       unsigned long color,
228			       enum drm_mm_search_flags sflags,
229			       enum drm_mm_allocator_flags aflags);
230/**
231 * drm_mm_insert_node - search for space and insert @node
232 * @mm: drm_mm to allocate from
233 * @node: preallocate node to insert
234 * @size: size of the allocation
235 * @alignment: alignment of the allocation
236 * @flags: flags to fine-tune the allocation
237 *
238 * This is a simplified version of drm_mm_insert_node_generic() with @color set
239 * to 0.
240 *
241 * The preallocated node must be cleared to 0.
242 *
243 * Returns:
244 * 0 on success, -ENOSPC if there's no suitable hole.
245 */
246static inline int drm_mm_insert_node(struct drm_mm *mm,
247				     struct drm_mm_node *node,
248				     u64 size,
249				     unsigned alignment,
250				     enum drm_mm_search_flags flags)
251{
252	return drm_mm_insert_node_generic(mm, node, size, alignment, 0, flags,
253					  DRM_MM_CREATE_DEFAULT);
254}
255
256int drm_mm_insert_node_in_range_generic(struct drm_mm *mm,
257					struct drm_mm_node *node,
258					u64 size,
259					unsigned alignment,
260					unsigned long color,
261					u64 start,
262					u64 end,
263					enum drm_mm_search_flags sflags,
264					enum drm_mm_allocator_flags aflags);
265/**
266 * drm_mm_insert_node_in_range - ranged search for space and insert @node
267 * @mm: drm_mm to allocate from
268 * @node: preallocate node to insert
269 * @size: size of the allocation
270 * @alignment: alignment of the allocation
271 * @start: start of the allowed range for this node
272 * @end: end of the allowed range for this node
273 * @flags: flags to fine-tune the allocation
274 *
275 * This is a simplified version of drm_mm_insert_node_in_range_generic() with
276 * @color set to 0.
277 *
278 * The preallocated node must be cleared to 0.
279 *
280 * Returns:
281 * 0 on success, -ENOSPC if there's no suitable hole.
282 */
283static inline int drm_mm_insert_node_in_range(struct drm_mm *mm,
284					      struct drm_mm_node *node,
285					      u64 size,
286					      unsigned alignment,
287					      u64 start,
288					      u64 end,
289					      enum drm_mm_search_flags flags)
290{
291	return drm_mm_insert_node_in_range_generic(mm, node, size, alignment,
292						   0, start, end, flags,
293						   DRM_MM_CREATE_DEFAULT);
294}
295
296void drm_mm_remove_node(struct drm_mm_node *node);
297void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new);
298void drm_mm_init(struct drm_mm *mm,
299		 u64 start,
300		 u64 size);
301void drm_mm_takedown(struct drm_mm *mm);
302bool drm_mm_clean(struct drm_mm *mm);
303
304void drm_mm_init_scan(struct drm_mm *mm,
305		      u64 size,
306		      unsigned alignment,
307		      unsigned long color);
308void drm_mm_init_scan_with_range(struct drm_mm *mm,
309				 u64 size,
310				 unsigned alignment,
311				 unsigned long color,
312				 u64 start,
313				 u64 end);
314bool drm_mm_scan_add_block(struct drm_mm_node *node);
315bool drm_mm_scan_remove_block(struct drm_mm_node *node);
316
317void drm_mm_debug_table(struct drm_mm *mm, const char *prefix);
318#ifdef CONFIG_DEBUG_FS
319int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm);
320#endif
321
322#endif
323