xref: /netbsd-src/sys/external/bsd/drm2/dist/include/drm/drm_mm.h (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /**************************************************************************
2  *
3  * Copyright 2006-2008 Tungsten Graphics, Inc., Cedar Park, TX. USA.
4  * All Rights Reserved.
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6  * Permission is hereby granted, free of charge, to any person obtaining a
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8  * "Software"), to deal in the Software without restriction, including
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11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
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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.
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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,
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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 #include <linux/spinlock.h>
47 
48 enum drm_mm_search_flags {
49 	DRM_MM_SEARCH_DEFAULT =		0,
50 	DRM_MM_SEARCH_BEST =		1 << 0,
51 	DRM_MM_SEARCH_BELOW =		1 << 1,
52 };
53 
54 enum drm_mm_allocator_flags {
55 	DRM_MM_CREATE_DEFAULT =		0,
56 	DRM_MM_CREATE_TOP =		1 << 0,
57 };
58 
59 #define DRM_MM_BOTTOMUP DRM_MM_SEARCH_DEFAULT, DRM_MM_CREATE_DEFAULT
60 #define DRM_MM_TOPDOWN DRM_MM_SEARCH_BELOW, DRM_MM_CREATE_TOP
61 
62 struct drm_mm_node {
63 	struct list_head node_list;
64 	struct list_head hole_stack;
65 	unsigned hole_follows : 1;
66 	unsigned scanned_block : 1;
67 	unsigned scanned_prev_free : 1;
68 	unsigned scanned_next_free : 1;
69 	unsigned scanned_preceeds_hole : 1;
70 	unsigned allocated : 1;
71 	unsigned long color;
72 	unsigned long start;
73 	unsigned long size;
74 	struct drm_mm *mm;
75 };
76 
77 struct drm_mm {
78 	/* List of all memory nodes that immediately precede a free hole. */
79 	struct list_head hole_stack;
80 	/* head_node.node_list is the list of all memory nodes, ordered
81 	 * according to the (increasing) start address of the memory node. */
82 	struct drm_mm_node head_node;
83 	unsigned int scan_check_range : 1;
84 	unsigned scan_alignment;
85 	unsigned long scan_color;
86 	unsigned long scan_size;
87 	unsigned long scan_hit_start;
88 	unsigned long scan_hit_end;
89 	unsigned scanned_blocks;
90 	unsigned long scan_start;
91 	unsigned long scan_end;
92 	struct drm_mm_node *prev_scanned_node;
93 
94 	void (*color_adjust)(struct drm_mm_node *node, unsigned long color,
95 			     unsigned long *start, unsigned long *end);
96 };
97 
98 /**
99  * drm_mm_node_allocated - checks whether a node is allocated
100  * @node: drm_mm_node to check
101  *
102  * Drivers should use this helpers for proper encapusulation of drm_mm
103  * internals.
104  *
105  * Returns:
106  * True if the @node is allocated.
107  */
108 static inline bool drm_mm_node_allocated(struct drm_mm_node *node)
109 {
110 	return node->allocated;
111 }
112 
113 /**
114  * drm_mm_initialized - checks whether an allocator is initialized
115  * @mm: drm_mm to check
116  *
117  * Drivers should use this helpers for proper encapusulation of drm_mm
118  * internals.
119  *
120  * Returns:
121  * True if the @mm is initialized.
122  */
123 static inline bool drm_mm_initialized(struct drm_mm *mm)
124 {
125 	return mm->hole_stack.next;
126 }
127 
128 static inline unsigned long __drm_mm_hole_node_start(struct drm_mm_node *hole_node)
129 {
130 	return hole_node->start + hole_node->size;
131 }
132 
133 /**
134  * drm_mm_hole_node_start - computes the start of the hole following @node
135  * @hole_node: drm_mm_node which implicitly tracks the following hole
136  *
137  * This is useful for driver-sepific debug dumpers. Otherwise drivers should not
138  * inspect holes themselves. Drivers must check first whether a hole indeed
139  * follows by looking at node->hole_follows.
140  *
141  * Returns:
142  * Start of the subsequent hole.
143  */
144 static inline unsigned long drm_mm_hole_node_start(struct drm_mm_node *hole_node)
145 {
146 	BUG_ON(!hole_node->hole_follows);
147 	return __drm_mm_hole_node_start(hole_node);
148 }
149 
150 static inline unsigned long __drm_mm_hole_node_end(struct drm_mm_node *hole_node)
151 {
152 	return list_entry(hole_node->node_list.next,
153 			  struct drm_mm_node, node_list)->start;
154 }
155 
156 /**
157  * drm_mm_hole_node_end - computes the end of the hole following @node
158  * @hole_node: drm_mm_node which implicitly tracks the following hole
159  *
160  * This is useful for driver-sepific debug dumpers. Otherwise drivers should not
161  * inspect holes themselves. Drivers must check first whether a hole indeed
162  * follows by looking at node->hole_follows.
163  *
164  * Returns:
165  * End of the subsequent hole.
166  */
167 static inline unsigned long drm_mm_hole_node_end(struct drm_mm_node *hole_node)
168 {
169 	return __drm_mm_hole_node_end(hole_node);
170 }
171 
172 /**
173  * drm_mm_for_each_node - iterator to walk over all allocated nodes
174  * @entry: drm_mm_node structure to assign to in each iteration step
175  * @mm: drm_mm allocator to walk
176  *
177  * This iterator walks over all nodes in the range allocator. It is implemented
178  * with list_for_each, so not save against removal of elements.
179  */
180 #define drm_mm_for_each_node(entry, mm) list_for_each_entry(entry, \
181 						&(mm)->head_node.node_list, \
182 						node_list)
183 
184 /**
185  * drm_mm_for_each_hole - iterator to walk over all holes
186  * @entry: drm_mm_node used internally to track progress
187  * @mm: drm_mm allocator to walk
188  * @hole_start: ulong variable to assign the hole start to on each iteration
189  * @hole_end: ulong variable to assign the hole end to on each iteration
190  *
191  * This iterator walks over all holes in the range allocator. It is implemented
192  * with list_for_each, so not save against removal of elements. @entry is used
193  * internally and will not reflect a real drm_mm_node for the very first hole.
194  * Hence users of this iterator may not access it.
195  *
196  * Implementation Note:
197  * We need to inline list_for_each_entry in order to be able to set hole_start
198  * and hole_end on each iteration while keeping the macro sane.
199  *
200  * The __drm_mm_for_each_hole version is similar, but with added support for
201  * going backwards.
202  */
203 #define drm_mm_for_each_hole(entry, mm, hole_start, hole_end) \
204 	for (entry = list_entry((mm)->hole_stack.next, struct drm_mm_node, hole_stack); \
205 	     &entry->hole_stack != &(mm)->hole_stack ? \
206 	     hole_start = drm_mm_hole_node_start(entry), \
207 	     hole_end = drm_mm_hole_node_end(entry), \
208 	     1 : 0; \
209 	     entry = list_entry(entry->hole_stack.next, struct drm_mm_node, hole_stack))
210 
211 #define __drm_mm_for_each_hole(entry, mm, hole_start, hole_end, backwards) \
212 	for (entry = list_entry((backwards) ? (mm)->hole_stack.prev : (mm)->hole_stack.next, struct drm_mm_node, hole_stack); \
213 	     &entry->hole_stack != &(mm)->hole_stack ? \
214 	     hole_start = drm_mm_hole_node_start(entry), \
215 	     hole_end = drm_mm_hole_node_end(entry), \
216 	     1 : 0; \
217 	     entry = list_entry((backwards) ? entry->hole_stack.prev : entry->hole_stack.next, struct drm_mm_node, hole_stack))
218 
219 /*
220  * Basic range manager support (drm_mm.c)
221  */
222 int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node);
223 
224 int drm_mm_insert_node_generic(struct drm_mm *mm,
225 			       struct drm_mm_node *node,
226 			       unsigned long size,
227 			       unsigned alignment,
228 			       unsigned long color,
229 			       enum drm_mm_search_flags sflags,
230 			       enum drm_mm_allocator_flags aflags);
231 /**
232  * drm_mm_insert_node - search for space and insert @node
233  * @mm: drm_mm to allocate from
234  * @node: preallocate node to insert
235  * @size: size of the allocation
236  * @alignment: alignment of the allocation
237  * @flags: flags to fine-tune the allocation
238  *
239  * This is a simplified version of drm_mm_insert_node_generic() with @color set
240  * to 0.
241  *
242  * The preallocated node must be cleared to 0.
243  *
244  * Returns:
245  * 0 on success, -ENOSPC if there's no suitable hole.
246  */
247 static inline int drm_mm_insert_node(struct drm_mm *mm,
248 				     struct drm_mm_node *node,
249 				     unsigned long size,
250 				     unsigned alignment,
251 				     enum drm_mm_search_flags flags)
252 {
253 	return drm_mm_insert_node_generic(mm, node, size, alignment, 0, flags,
254 					  DRM_MM_CREATE_DEFAULT);
255 }
256 
257 int drm_mm_insert_node_in_range_generic(struct drm_mm *mm,
258 					struct drm_mm_node *node,
259 					unsigned long size,
260 					unsigned alignment,
261 					unsigned long color,
262 					unsigned long start,
263 					unsigned long end,
264 					enum drm_mm_search_flags sflags,
265 					enum drm_mm_allocator_flags aflags);
266 /**
267  * drm_mm_insert_node_in_range - ranged search for space and insert @node
268  * @mm: drm_mm to allocate from
269  * @node: preallocate node to insert
270  * @size: size of the allocation
271  * @alignment: alignment of the allocation
272  * @start: start of the allowed range for this node
273  * @end: end of the allowed range for this node
274  * @flags: flags to fine-tune the allocation
275  *
276  * This is a simplified version of drm_mm_insert_node_in_range_generic() with
277  * @color set to 0.
278  *
279  * The preallocated node must be cleared to 0.
280  *
281  * Returns:
282  * 0 on success, -ENOSPC if there's no suitable hole.
283  */
284 static inline int drm_mm_insert_node_in_range(struct drm_mm *mm,
285 					      struct drm_mm_node *node,
286 					      unsigned long size,
287 					      unsigned alignment,
288 					      unsigned long start,
289 					      unsigned long end,
290 					      enum drm_mm_search_flags flags)
291 {
292 	return drm_mm_insert_node_in_range_generic(mm, node, size, alignment,
293 						   0, start, end, flags,
294 						   DRM_MM_CREATE_DEFAULT);
295 }
296 
297 void drm_mm_remove_node(struct drm_mm_node *node);
298 void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new);
299 void drm_mm_init(struct drm_mm *mm,
300 		 unsigned long start,
301 		 unsigned long size);
302 void drm_mm_takedown(struct drm_mm *mm);
303 bool drm_mm_clean(struct drm_mm *mm);
304 
305 void drm_mm_init_scan(struct drm_mm *mm,
306 		      unsigned long size,
307 		      unsigned alignment,
308 		      unsigned long color);
309 void drm_mm_init_scan_with_range(struct drm_mm *mm,
310 				 unsigned long size,
311 				 unsigned alignment,
312 				 unsigned long color,
313 				 unsigned long start,
314 				 unsigned long end);
315 bool drm_mm_scan_add_block(struct drm_mm_node *node);
316 bool drm_mm_scan_remove_block(struct drm_mm_node *node);
317 
318 void drm_mm_debug_table(struct drm_mm *mm, const char *prefix);
319 #ifdef CONFIG_DEBUG_FS
320 int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm);
321 #endif
322 
323 #endif
324