drm/ttm/ttm_execbuf_util.h

0001 /**************************************************************************
0002  *
0003  * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
0004  * All Rights Reserved.
0005  *
0006  * Permission is hereby granted, free of charge, to any person obtaining a
0007  * copy of this software and associated documentation files (the
0008  * "Software"), to deal in the Software without restriction, including
0009  * without limitation the rights to use, copy, modify, merge, publish,
0010  * distribute, sub license, and/or sell copies of the Software, and to
0011  * permit persons to whom the Software is furnished to do so, subject to
0012  * the following conditions:
0013  *
0014  * The above copyright notice and this permission notice (including the
0015  * next paragraph) shall be included in all copies or substantial portions
0016  * of the Software.
0017  *
0018  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
0019  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
0020  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
0021  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
0022  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
0023  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
0024  * USE OR OTHER DEALINGS IN THE SOFTWARE.
0025  *
0026  **************************************************************************/
0027 /*
0028  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
0029  */
0030
0031 #ifndef _TTM_EXECBUF_UTIL_H_
0032 #define _TTM_EXECBUF_UTIL_H_
0033
0034 #include <linux/list.h>
0035
0036 #include "ttm_bo_api.h"
0037
0038 /**
0039  * struct ttm_validate_buffer
0040  *
0041  * @head:           list head for thread-private list.
0042  * @bo:             refcounted buffer object pointer.
0043  * @num_shared:     How many shared fences we want to add.
0044  */
0045
0046 struct ttm_validate_buffer {
0047     struct list_head head;
0048     struct ttm_buffer_object *bo;
0049     unsigned int num_shared;
0050 };
0051
0052 /**
0053  * function ttm_eu_backoff_reservation
0054  *
0055  * @ticket:   ww_acquire_ctx from reserve call
0056  * @list:     thread private list of ttm_validate_buffer structs.
0057  *
0058  * Undoes all buffer validation reservations for bos pointed to by
0059  * the list entries.
0060  */
0061 void ttm_eu_backoff_reservation(struct ww_acquire_ctx *ticket,
0062                 struct list_head *list);
0063
0064 /**
0065  * function ttm_eu_reserve_buffers
0066  *
0067  * @ticket:  [out] ww_acquire_ctx filled in by call, or NULL if only
0068  *           non-blocking reserves should be tried.
0069  * @list:    thread private list of ttm_validate_buffer structs.
0070  * @intr:    should the wait be interruptible
0071  * @dups:    [out] optional list of duplicates.
0072  * @del_lru: true if BOs should be removed from the LRU.
0073  *
0074  * Tries to reserve bos pointed to by the list entries for validation.
0075  * If the function returns 0, all buffers are marked as "unfenced",
0076  * taken off the lru lists and are not synced for write CPU usage.
0077  *
0078  * If the function detects a deadlock due to multiple threads trying to
0079  * reserve the same buffers in reverse order, all threads except one will
0080  * back off and retry. This function may sleep while waiting for
0081  * CPU write reservations to be cleared, and for other threads to
0082  * unreserve their buffers.
0083  *
0084  * If intr is set to true, this function may return -ERESTARTSYS if the
0085  * calling process receives a signal while waiting. In that case, no
0086  * buffers on the list will be reserved upon return.
0087  *
0088  * If dups is non NULL all buffers already reserved by the current thread
0089  * (e.g. duplicates) are added to this list, otherwise -EALREADY is returned
0090  * on the first already reserved buffer and all buffers from the list are
0091  * unreserved again.
0092  *
0093  * Buffers reserved by this function should be unreserved by
0094  * a call to either ttm_eu_backoff_reservation() or
0095  * ttm_eu_fence_buffer_objects() when command submission is complete or
0096  * has failed.
0097  */
0098 int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket,
0099                struct list_head *list, bool intr,
0100                struct list_head *dups);
0101
0102 /**
0103  * function ttm_eu_fence_buffer_objects.
0104  *
0105  * @ticket:      ww_acquire_ctx from reserve call
0106  * @list:        thread private list of ttm_validate_buffer structs.
0107  * @fence:       The new exclusive fence for the buffers.
0108  *
0109  * This function should be called when command submission is complete, and
0110  * it will add a new sync object to bos pointed to by entries on @list.
0111  * It also unreserves all buffers, putting them on lru lists.
0112  *
0113  */
0114 void ttm_eu_fence_buffer_objects(struct ww_acquire_ctx *ticket,
0115                  struct list_head *list,
0116                  struct dma_fence *fence);
0117
0118 #endif