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
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25 *
26 **************************************************************************/
27/*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30/* $FreeBSD$ */
31
32#ifndef _TTM_EXECBUF_UTIL_H_
33#define _TTM_EXECBUF_UTIL_H_
34
35#include <dev/drm2/ttm/ttm_bo_api.h>
36
37/**
38 * struct ttm_validate_buffer
39 *
40 * @head:           list head for thread-private list.
41 * @bo:             refcounted buffer object pointer.
42 * @reserved:       Indicates whether @bo has been reserved for validation.
43 * @removed:        Indicates whether @bo has been removed from lru lists.
44 * @put_count:      Number of outstanding references on bo::list_kref.
45 * @old_sync_obj:   Pointer to a sync object about to be unreferenced
46 */
47
48struct ttm_validate_buffer {
49	struct list_head head;
50	struct ttm_buffer_object *bo;
51	bool reserved;
52	bool removed;
53	int put_count;
54	void *old_sync_obj;
55};
56
57/**
58 * function ttm_eu_backoff_reservation
59 *
60 * @list:     thread private list of ttm_validate_buffer structs.
61 *
62 * Undoes all buffer validation reservations for bos pointed to by
63 * the list entries.
64 */
65
66extern void ttm_eu_backoff_reservation(struct list_head *list);
67
68/**
69 * function ttm_eu_reserve_buffers
70 *
71 * @list:    thread private list of ttm_validate_buffer structs.
72 *
73 * Tries to reserve bos pointed to by the list entries for validation.
74 * If the function returns 0, all buffers are marked as "unfenced",
75 * taken off the lru lists and are not synced for write CPU usage.
76 *
77 * If the function detects a deadlock due to multiple threads trying to
78 * reserve the same buffers in reverse order, all threads except one will
79 * back off and retry. This function may sleep while waiting for
80 * CPU write reservations to be cleared, and for other threads to
81 * unreserve their buffers.
82 *
83 * This function may return -ERESTART or -EAGAIN if the calling process
84 * receives a signal while waiting. In that case, no buffers on the list
85 * will be reserved upon return.
86 *
87 * Buffers reserved by this function should be unreserved by
88 * a call to either ttm_eu_backoff_reservation() or
89 * ttm_eu_fence_buffer_objects() when command submission is complete or
90 * has failed.
91 */
92
93extern int ttm_eu_reserve_buffers(struct list_head *list);
94
95/**
96 * function ttm_eu_fence_buffer_objects.
97 *
98 * @list:        thread private list of ttm_validate_buffer structs.
99 * @sync_obj:    The new sync object for the buffers.
100 *
101 * This function should be called when command submission is complete, and
102 * it will add a new sync object to bos pointed to by entries on @list.
103 * It also unreserves all buffers, putting them on lru lists.
104 *
105 */
106
107extern void ttm_eu_fence_buffer_objects(struct list_head *list, void *sync_obj);
108
109#endif
110