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,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
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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/bug.h>
34 #include <linux/wait.h>
35 #include <linux/errno.h>
36 #include <linux/kobject.h>
37 #include <linux/mm.h>
38 
39 /**
40  * struct ttm_mem_shrink - callback to shrink TTM memory usage.
41  *
42  * @do_shrink: The callback function.
43  *
44  * Arguments to the do_shrink functions are intended to be passed using
45  * inheritance. That is, the argument class derives from struct ttm_mem_shrink,
46  * and can be accessed using container_of().
47  */
48 
49 struct ttm_mem_shrink {
50 	int (*do_shrink) (struct ttm_mem_shrink *);
51 };
52 
53 /**
54  * struct ttm_mem_global - Global memory accounting structure.
55  *
56  * @shrink: A single callback to shrink TTM memory usage. Extend this
57  * to a linked list to be able to handle multiple callbacks when needed.
58  * @swap_queue: A workqueue to handle shrinking in low memory situations. We
59  * need a separate workqueue since it will spend a lot of time waiting
60  * for the GPU, and this will otherwise block other workqueue tasks(?)
61  * At this point we use only a single-threaded workqueue.
62  * @work: The workqueue callback for the shrink queue.
63  * @queue: Wait queue for processes suspended waiting for memory.
64  * @lock: Lock to protect the @shrink - and the memory accounting members,
65  * that is, essentially the whole structure with some exceptions.
66  * @zones: Array of pointers to accounting zones.
67  * @num_zones: Number of populated entries in the @zones array.
68  * @zone_kernel: Pointer to the kernel zone.
69  * @zone_highmem: Pointer to the highmem zone if there is one.
70  * @zone_dma32: Pointer to the dma32 zone if there is one.
71  *
72  * Note that this structure is not per device. It should be global for all
73  * graphics devices.
74  */
75 
76 #define TTM_MEM_MAX_ZONES 2
77 struct ttm_mem_zone;
78 struct ttm_mem_global {
79 	struct kobject kobj;
80 	struct ttm_mem_shrink *shrink;
81 	struct workqueue_struct *swap_queue;
82 	struct work_struct work;
83 	wait_queue_head_t queue;
84 	spinlock_t lock;
85 	struct ttm_mem_zone *zones[TTM_MEM_MAX_ZONES];
86 	unsigned int num_zones;
87 	struct ttm_mem_zone *zone_kernel;
88 #ifdef CONFIG_HIGHMEM
89 	struct ttm_mem_zone *zone_highmem;
90 #else
91 	struct ttm_mem_zone *zone_dma32;
92 #endif
93 };
94 
95 /**
96  * ttm_mem_init_shrink - initialize a struct ttm_mem_shrink object
97  *
98  * @shrink: The object to initialize.
99  * @func: The callback function.
100  */
101 
ttm_mem_init_shrink(struct ttm_mem_shrink * shrink,int (* func)(struct ttm_mem_shrink *))102 static inline void ttm_mem_init_shrink(struct ttm_mem_shrink *shrink,
103 				       int (*func) (struct ttm_mem_shrink *))
104 {
105 	shrink->do_shrink = func;
106 }
107 
108 /**
109  * ttm_mem_register_shrink - register a struct ttm_mem_shrink object.
110  *
111  * @glob: The struct ttm_mem_global object to register with.
112  * @shrink: An initialized struct ttm_mem_shrink object to register.
113  *
114  * Returns:
115  * -EBUSY: There's already a callback registered. (May change).
116  */
117 
ttm_mem_register_shrink(struct ttm_mem_global * glob,struct ttm_mem_shrink * shrink)118 static inline int ttm_mem_register_shrink(struct ttm_mem_global *glob,
119 					  struct ttm_mem_shrink *shrink)
120 {
121 	spin_lock(&glob->lock);
122 	if (glob->shrink != NULL) {
123 		spin_unlock(&glob->lock);
124 		return -EBUSY;
125 	}
126 	glob->shrink = shrink;
127 	spin_unlock(&glob->lock);
128 	return 0;
129 }
130 
131 /**
132  * ttm_mem_unregister_shrink - unregister a struct ttm_mem_shrink object.
133  *
134  * @glob: The struct ttm_mem_global object to unregister from.
135  * @shrink: A previously registert struct ttm_mem_shrink object.
136  *
137  */
138 
ttm_mem_unregister_shrink(struct ttm_mem_global * glob,struct ttm_mem_shrink * shrink)139 static inline void ttm_mem_unregister_shrink(struct ttm_mem_global *glob,
140 					     struct ttm_mem_shrink *shrink)
141 {
142 	spin_lock(&glob->lock);
143 	BUG_ON(glob->shrink != shrink);
144 	glob->shrink = NULL;
145 	spin_unlock(&glob->lock);
146 }
147 
148 extern int ttm_mem_global_init(struct ttm_mem_global *glob);
149 extern void ttm_mem_global_release(struct ttm_mem_global *glob);
150 extern int ttm_mem_global_alloc(struct ttm_mem_global *glob, uint64_t memory,
151 				bool no_wait, bool interruptible);
152 extern void ttm_mem_global_free(struct ttm_mem_global *glob,
153 				uint64_t amount);
154 extern int ttm_mem_global_alloc_page(struct ttm_mem_global *glob,
155 				     struct page *page,
156 				     bool no_wait, bool interruptible);
157 extern void ttm_mem_global_free_page(struct ttm_mem_global *glob,
158 				     struct page *page);
159 extern size_t ttm_round_pot(size_t size);
160 #endif
161