include/drm/ttm/ttm_execbuf_util.h

   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,
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  25  *
  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 "ttm/ttm_bo_api.h"
  35 #include <linux/list.h>
  36
  37 /**
  38  * struct ttm_validate_buffer
  39  *
  40  * @head:           list head for thread-private list.
  41  * @bo:             refcounted buffer object pointer.
  42  * @new_sync_obj_arg: New sync_obj_arg for @bo, to be used once
  43  * adding a new sync object.
  44  * @reserved:       Indicates whether @bo has been reserved for validation.
  45  * @removed:        Indicates whether @bo has been removed from lru lists.
  46  * @put_count:      Number of outstanding references on bo::list_kref.
  47  * @old_sync_obj:   Pointer to a sync object about to be unreferenced
  48  */
  49
  50 struct ttm_validate_buffer {
  51         struct list_head head;
  52         struct ttm_buffer_object *bo;
  53         void *new_sync_obj_arg;
  54         bool reserved;
  55         bool removed;
  56         int put_count;
  57         void *old_sync_obj;
  58 };
  59
  60 /**
  61  * function ttm_eu_backoff_reservation
  62  *
  63  * @list:     thread private list of ttm_validate_buffer structs.
  64  *
  65  * Undoes all buffer validation reservations for bos pointed to by
  66  * the list entries.
  67  */
  68
  69 extern void ttm_eu_backoff_reservation(struct list_head *list);
  70
  71 /**
  72  * function ttm_eu_reserve_buffers
  73  *
  74  * @list:    thread private list of ttm_validate_buffer structs.
  75  *
  76  * Tries to reserve bos pointed to by the list entries for validation.
  77  * If the function returns 0, all buffers are marked as "unfenced",
  78  * taken off the lru lists and are not synced for write CPU usage.
  79  *
  80  * If the function detects a deadlock due to multiple threads trying to
  81  * reserve the same buffers in reverse order, all threads except one will
  82  * back off and retry. This function may sleep while waiting for
  83  * CPU write reservations to be cleared, and for other threads to
  84  * unreserve their buffers.
  85  *
  86  * This function may return -ERESTART or -EAGAIN if the calling process
  87  * receives a signal while waiting. In that case, no buffers on the list
  88  * will be reserved upon return.
  89  *
  90  * Buffers reserved by this function should be unreserved by
  91  * a call to either ttm_eu_backoff_reservation() or
  92  * ttm_eu_fence_buffer_objects() when command submission is complete or
  93  * has failed.
  94  */
  95
  96 extern int ttm_eu_reserve_buffers(struct list_head *list);
  97
  98 /**
  99  * function ttm_eu_fence_buffer_objects.
 100  *
 101  * @list:        thread private list of ttm_validate_buffer structs.
 102  * @sync_obj:    The new sync object for the buffers.
 103  *
 104  * This function should be called when command submission is complete, and
 105  * it will add a new sync object to bos pointed to by entries on @list.
 106  * It also unreserves all buffers, putting them on lru lists.
 107  *
 108  */
 109
 110 extern void ttm_eu_fence_buffer_objects(struct list_head *list, void *sync_obj);
 111
 112 #endif