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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24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
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26 **************************************************************************/
27 /*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30
31 #ifndef _TTM_EXECBUF_UTIL_H_
32 #define _TTM_EXECBUF_UTIL_H_
33
34 #include <linux/list.h>
35
36 #include "ttm_bo_api.h"
37
38 /**
39 * struct ttm_validate_buffer
40 *
41 * @head: list head for thread-private list.
42 * @bo: refcounted buffer object pointer.
43 * @num_shared: How many shared fences we want to add.
44 */
45
46 struct ttm_validate_buffer {
47 struct list_head head;
48 struct ttm_buffer_object *bo;
49 unsigned int num_shared;
50 };
51
52 /**
53 * function ttm_eu_backoff_reservation
54 *
55 * @ticket: ww_acquire_ctx from reserve call
56 * @list: thread private list of ttm_validate_buffer structs.
57 *
58 * Undoes all buffer validation reservations for bos pointed to by
59 * the list entries.
60 */
61
62 extern void ttm_eu_backoff_reservation(struct ww_acquire_ctx *ticket,
63 struct list_head *list);
64
65 /**
66 * function ttm_eu_reserve_buffers
67 *
68 * @ticket: [out] ww_acquire_ctx filled in by call, or NULL if only
69 * non-blocking reserves should be tried.
70 * @list: thread private list of ttm_validate_buffer structs.
71 * @intr: should the wait be interruptible
72 * @dups: [out] optional list of duplicates.
73 * @del_lru: true if BOs should be removed from the LRU.
74 *
75 * Tries to reserve bos pointed to by the list entries for validation.
76 * If the function returns 0, all buffers are marked as "unfenced",
77 * taken off the lru lists and are not synced for write CPU usage.
78 *
79 * If the function detects a deadlock due to multiple threads trying to
80 * reserve the same buffers in reverse order, all threads except one will
81 * back off and retry. This function may sleep while waiting for
82 * CPU write reservations to be cleared, and for other threads to
83 * unreserve their buffers.
84 *
85 * If intr is set to true, this function may return -ERESTARTSYS if the
86 * calling process receives a signal while waiting. In that case, no
87 * buffers on the list will be reserved upon return.
88 *
89 * If dups is non NULL all buffers already reserved by the current thread
90 * (e.g. duplicates) are added to this list, otherwise -EALREADY is returned
91 * on the first already reserved buffer and all buffers from the list are
92 * unreserved again.
93 *
94 * Buffers reserved by this function should be unreserved by
95 * a call to either ttm_eu_backoff_reservation() or
96 * ttm_eu_fence_buffer_objects() when command submission is complete or
97 * has failed.
98 */
99
100 extern int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket,
101 struct list_head *list, bool intr,
102 struct list_head *dups, bool del_lru);
103
104 /**
105 * function ttm_eu_fence_buffer_objects.
106 *
107 * @ticket: ww_acquire_ctx from reserve call
108 * @list: thread private list of ttm_validate_buffer structs.
109 * @fence: The new exclusive fence for the buffers.
110 *
111 * This function should be called when command submission is complete, and
112 * it will add a new sync object to bos pointed to by entries on @list.
113 * It also unreserves all buffers, putting them on lru lists.
114 *
115 */
116
117 extern void ttm_eu_fence_buffer_objects(struct ww_acquire_ctx *ticket,
118 struct list_head *list,
119 struct dma_fence *fence);
120
121 #endif