src/gallium/auxiliary/pipebuffer/pb_buffer.h

   1 /**************************************************************************
   2  *
   3  * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
   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
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28 /**
  29  * \file
  30  * Generic code for buffers.
  31  *
  32  * Behind a pipe buffle handle there can be DMA buffers, client (or user)
  33  * buffers, regular malloced buffers, etc. This file provides an abstract base
  34  * buffer handle that allows the driver to cope with all those kinds of buffers
  35  * in a more flexible way.
  36  *
  37  * There is no obligation of a winsys driver to use this library. And a pipe
  38  * driver should be completly agnostic about it.
  39  *
  40  * \author José Fonseca <jrfonseca@tungstengraphics.com>
  41  */
  42
  43 #ifndef PB_BUFFER_H_
  44 #define PB_BUFFER_H_
  45
  46
  47 #include "pipe/p_compiler.h"
  48 #include "pipe/p_debug.h"
  49 #include "pipe/p_state.h"
  50 #include "pipe/p_inlines.h"
  51
  52
  53 struct pb_vtbl;
  54
  55 /**
  56  * Buffer description.
  57  *
  58  * Used when allocating the buffer.
  59  */
  60 struct pb_desc
  61 {
  62    unsigned alignment;
  63    unsigned usage;
  64 };
  65
  66
  67 /**
  68  * Base class for all pb_* buffers.
  69  */
  70 struct pb_buffer
  71 {
  72    struct pipe_buffer base;
  73
  74    /**
  75     * Pointer to the virtual function table.
  76     *
  77     * Avoid accessing this table directly. Use the inline functions below
  78     * instead to avoid mistakes.
  79     */
  80    const struct pb_vtbl *vtbl;
  81 };
  82
  83
  84 /**
  85  * Virtual function table for the buffer storage operations.
  86  *
  87  * Note that creation is not done through this table.
  88  */
  89 struct pb_vtbl
  90 {
  91    void (*destroy)( struct pb_buffer *buf );
  92
  93    /**
  94     * Map the entire data store of a buffer object into the client's address.
  95     * flags is bitmask of PIPE_BUFFER_FLAG_READ/WRITE.
  96     */
  97    void *(*map)( struct pb_buffer *buf,
  98                  unsigned flags );
  99
 100    void (*unmap)( struct pb_buffer *buf );
 101
 102    /**
 103     * Get the base buffer and the offset.
 104     *
 105     * A buffer can be subdivided in smaller buffers. This method should return
 106     * the underlaying buffer, and the relative offset.
 107     *
 108     * Buffers without an underlaying base buffer should return themselves, with
 109     * a zero offset.
 110     *
 111     * Note that this will increase the reference count of the base buffer.
 112     */
 113    void (*get_base_buffer)( struct pb_buffer *buf,
 114                             struct pb_buffer **base_buf,
 115                             unsigned *offset );
 116 };
 117
 118
 119 static INLINE struct pipe_buffer *
 120 pb_pipe_buffer( struct pb_buffer *pbuf )
 121 {
 122    assert(pbuf);
 123    return &pbuf->base;
 124 }
 125
 126
 127 static INLINE struct pb_buffer *
 128 pb_buffer( struct pipe_buffer *buf )
 129 {
 130    assert(buf);
 131    /* Could add a magic cookie check on debug builds.
 132     */
 133    return (struct pb_buffer *)buf;
 134 }
 135
 136
 137 /* Accessor functions for pb->vtbl:
 138  */
 139 static INLINE void *
 140 pb_map(struct pb_buffer *buf,
 141        unsigned flags)
 142 {
 143    assert(buf);
 144    return buf->vtbl->map(buf, flags);
 145 }
 146
 147
 148 static INLINE void
 149 pb_unmap(struct pb_buffer *buf)
 150 {
 151    assert(buf);
 152    buf->vtbl->unmap(buf);
 153 }
 154
 155
 156 static INLINE void
 157 pb_get_base_buffer( struct pb_buffer *buf,
 158                     struct pb_buffer **base_buf,
 159                     unsigned *offset )
 160 {
 161    buf->vtbl->get_base_buffer(buf, base_buf, offset);
 162 }
 163
 164
 165 static INLINE void
 166 pb_destroy(struct pb_buffer *buf)
 167 {
 168    assert(buf);
 169    buf->vtbl->destroy(buf);
 170 }
 171
 172
 173 /* XXX: thread safety issues!
 174  */
 175 static INLINE void
 176 pb_reference(struct pb_buffer **dst,
 177              struct pb_buffer *src)
 178 {
 179    if (src)
 180       src->base.refcount++;
 181
 182    if (*dst && --(*dst)->base.refcount == 0)
 183       pb_destroy( *dst );
 184
 185    *dst = src;
 186 }
 187
 188
 189 /**
 190  * Malloc-based buffer to store data that can't be used by the graphics
 191  * hardware.
 192  */
 193 struct pb_buffer *
 194 pb_malloc_buffer_create(size_t size,
 195                         const struct pb_desc *desc);
 196
 197
 198 void
 199 pb_init_winsys(struct pipe_winsys *winsys);
 200
 201
 202 #endif /*PB_BUFFER_H_*/