1 /**************************************************************************
2  *
3  * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., 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,
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26  **************************************************************************/
27 
28 #ifndef TTM_MEMORY_H
29 #define TTM_MEMORY_H
30 
31 #include <linux/workqueue.h>
32 #include <linux/spinlock.h>
33 #include <linux/wait.h>
34 #include <linux/errno.h>
35 #include <linux/kobject.h>
36 #include <linux/mm.h>
37 
38 /**
39  * struct ttm_mem_shrink - callback to shrink TTM memory usage.
40  *
41  * @do_shrink: The callback function.
42  *
43  * Arguments to the do_shrink functions are intended to be passed using
44  * inheritance. That is, the argument class derives from struct ttm_mem_srink,
45  * and can be accessed using container_of().
46  */
47 
48 struct ttm_mem_shrink {
49 	int (*do_shrink) (struct ttm_mem_shrink *);
50 };
51 
52 /**
53  * struct ttm_mem_global - Global memory accounting structure.
54  *
55  * @shrink: A single callback to shrink TTM memory usage. Extend this
56  * to a linked list to be able to handle multiple callbacks when needed.
57  * @swap_queue: A workqueue to handle shrinking in low memory situations. We
58  * need a separate workqueue since it will spend a lot of time waiting
59  * for the GPU, and this will otherwise block other workqueue tasks(?)
60  * At this point we use only a single-threaded workqueue.
61  * @work: The workqueue callback for the shrink queue.
62  * @queue: Wait queue for processes suspended waiting for memory.
63  * @lock: Lock to protect the @shrink - and the memory accounting members,
64  * that is, essentially the whole structure with some exceptions.
65  * @zones: Array of pointers to accounting zones.
66  * @num_zones: Number of populated entries in the @zones array.
67  * @zone_kernel: Pointer to the kernel zone.
68  * @zone_highmem: Pointer to the highmem zone if there is one.
69  * @zone_dma32: Pointer to the dma32 zone if there is one.
70  *
71  * Note that this structure is not per device. It should be global for all
72  * graphics devices.
73  */
74 
75 #define TTM_MEM_MAX_ZONES 2
76 struct ttm_mem_zone;
77 struct ttm_mem_global {
78 	struct kobject kobj;
79 	struct ttm_mem_shrink *shrink;
80 	struct workqueue_struct *swap_queue;
81 	struct work_struct work;
82 	wait_queue_head_t queue;
83 	spinlock_t lock;
84 	struct ttm_mem_zone *zones[TTM_MEM_MAX_ZONES];
85 	unsigned int num_zones;
86 	struct ttm_mem_zone *zone_kernel;
87 #ifdef CONFIG_HIGHMEM
88 	struct ttm_mem_zone *zone_highmem;
89 #else
90 	struct ttm_mem_zone *zone_dma32;
91 #endif
92 };
93 
94 /**
95  * ttm_mem_init_shrink - initialize a struct ttm_mem_shrink object
96  *
97  * @shrink: The object to initialize.
98  * @func: The callback function.
99  */
100 
ttm_mem_init_shrink(struct ttm_mem_shrink * shrink,int (* func)(struct ttm_mem_shrink *))101 static inline void ttm_mem_init_shrink(struct ttm_mem_shrink *shrink,
102 				       int (*func) (struct ttm_mem_shrink *))
103 {
104 	shrink->do_shrink = func;
105 }
106 
107 /**
108  * ttm_mem_register_shrink - register a struct ttm_mem_shrink object.
109  *
110  * @glob: The struct ttm_mem_global object to register with.
111  * @shrink: An initialized struct ttm_mem_shrink object to register.
112  *
113  * Returns:
114  * -EBUSY: There's already a callback registered. (May change).
115  */
116 
ttm_mem_register_shrink(struct ttm_mem_global * glob,struct ttm_mem_shrink * shrink)117 static inline int ttm_mem_register_shrink(struct ttm_mem_global *glob,
118 					  struct ttm_mem_shrink *shrink)
119 {
120 	spin_lock(&glob->lock);
121 	if (glob->shrink != NULL) {
122 		spin_unlock(&glob->lock);
123 		return -EBUSY;
124 	}
125 	glob->shrink = shrink;
126 	spin_unlock(&glob->lock);
127 	return 0;
128 }
129 
130 /**
131  * ttm_mem_unregister_shrink - unregister a struct ttm_mem_shrink object.
132  *
133  * @glob: The struct ttm_mem_global object to unregister from.
134  * @shrink: A previously registert struct ttm_mem_shrink object.
135  *
136  */
137 
ttm_mem_unregister_shrink(struct ttm_mem_global * glob,struct ttm_mem_shrink * shrink)138 static inline void ttm_mem_unregister_shrink(struct ttm_mem_global *glob,
139 					     struct ttm_mem_shrink *shrink)
140 {
141 	spin_lock(&glob->lock);
142 	BUG_ON(glob->shrink != shrink);
143 	glob->shrink = NULL;
144 	spin_unlock(&glob->lock);
145 }
146 
147 extern int ttm_mem_global_init(struct ttm_mem_global *glob);
148 extern void ttm_mem_global_release(struct ttm_mem_global *glob);
149 extern int ttm_mem_global_alloc(struct ttm_mem_global *glob, uint64_t memory,
150 				bool no_wait, bool interruptible);
151 extern void ttm_mem_global_free(struct ttm_mem_global *glob,
152 				uint64_t amount);
153 extern int ttm_mem_global_alloc_page(struct ttm_mem_global *glob,
154 				     struct page *page,
155 				     bool no_wait, bool interruptible);
156 extern void ttm_mem_global_free_page(struct ttm_mem_global *glob,
157 				     struct page *page);
158 extern size_t ttm_round_pot(size_t size);
159 #endif
160