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
 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#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
 49struct 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
 77struct ttm_mem_zone;
 78struct 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
102static 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
118static 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
139static 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
148extern int ttm_mem_global_init(struct ttm_mem_global *glob);
149extern void ttm_mem_global_release(struct ttm_mem_global *glob);
150extern int ttm_mem_global_alloc(struct ttm_mem_global *glob, uint64_t memory,
151				bool no_wait, bool interruptible);
152extern void ttm_mem_global_free(struct ttm_mem_global *glob,
153				uint64_t amount);
154extern int ttm_mem_global_alloc_page(struct ttm_mem_global *glob,
155				     struct page *page,
156				     bool no_wait, bool interruptible);
157extern void ttm_mem_global_free_page(struct ttm_mem_global *glob,
158				     struct page *page);
159extern size_t ttm_round_pot(size_t size);
160#endif