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 Jose 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 "util/u_debug.h"
49 #include "util/u_inlines.h"
50 #include "pipe/p_defines.h"
51 
52 
53 #ifdef __cplusplus
54 extern "C" {
55 #endif
56 
57 
58 struct pb_vtbl;
59 struct pb_validate;
60 struct pipe_fence_handle;
61 
62 
63 #define PB_USAGE_CPU_READ  (1 << 0)
64 #define PB_USAGE_CPU_WRITE (1 << 1)
65 #define PB_USAGE_GPU_READ  (1 << 2)
66 #define PB_USAGE_GPU_WRITE (1 << 3)
67 #define PB_USAGE_UNSYNCHRONIZED (1 << 10)
68 #define PB_USAGE_DONTBLOCK (1 << 9)
69 
70 #define PB_USAGE_CPU_READ_WRITE \
71    ( PB_USAGE_CPU_READ | PB_USAGE_CPU_WRITE )
72 #define PB_USAGE_GPU_READ_WRITE \
73    ( PB_USAGE_GPU_READ | PB_USAGE_GPU_WRITE )
74 #define PB_USAGE_WRITE \
75    ( PB_USAGE_CPU_WRITE | PB_USAGE_GPU_WRITE )
76 
77 /**
78  * Buffer description.
79  *
80  * Used when allocating the buffer.
81  */
82 struct pb_desc
83 {
84    unsigned alignment;
85    unsigned usage;
86 };
87 
88 
89 /**
90  * Size. Regular (32bit) unsigned for now.
91  */
92 typedef unsigned pb_size;
93 
94 
95 /**
96  * Base class for all pb_* buffers.
97  */
98 struct pb_buffer
99 {
100    struct pipe_reference  reference;
101    unsigned               size;
102    unsigned               alignment;
103    unsigned               usage;
104 
105    /**
106     * Pointer to the virtual function table.
107     *
108     * Avoid accessing this table directly. Use the inline functions below
109     * instead to avoid mistakes.
110     */
111    const struct pb_vtbl *vtbl;
112 };
113 
114 
115 /**
116  * Virtual function table for the buffer storage operations.
117  *
118  * Note that creation is not done through this table.
119  */
120 struct pb_vtbl
121 {
122    void (*destroy)( struct pb_buffer *buf );
123 
124    /**
125     * Map the entire data store of a buffer object into the client's address.
126     * flags is bitmask of PB_USAGE_CPU_READ/WRITE.
127     */
128    void *(*map)( struct pb_buffer *buf,
129                  unsigned flags, void *flush_ctx );
130 
131    void (*unmap)( struct pb_buffer *buf );
132 
133    enum pipe_error (*validate)( struct pb_buffer *buf,
134                                 struct pb_validate *vl,
135                                 unsigned flags );
136 
137    void (*fence)( struct pb_buffer *buf,
138                   struct pipe_fence_handle *fence );
139 
140    /**
141     * Get the base buffer and the offset.
142     *
143     * A buffer can be subdivided in smaller buffers. This method should return
144     * the underlaying buffer, and the relative offset.
145     *
146     * Buffers without an underlaying base buffer should return themselves, with
147     * a zero offset.
148     *
149     * Note that this will increase the reference count of the base buffer.
150     */
151    void (*get_base_buffer)( struct pb_buffer *buf,
152                             struct pb_buffer **base_buf,
153                             pb_size *offset );
154 
155 };
156 
157 
158 
159 /* Accessor functions for pb->vtbl:
160  */
161 static INLINE void *
pb_map(struct pb_buffer * buf,unsigned flags,void * flush_ctx)162 pb_map(struct pb_buffer *buf,
163        unsigned flags, void *flush_ctx)
164 {
165    assert(buf);
166    if(!buf)
167       return NULL;
168    assert(pipe_is_referenced(&buf->reference));
169    return buf->vtbl->map(buf, flags, flush_ctx);
170 }
171 
172 
173 static INLINE void
pb_unmap(struct pb_buffer * buf)174 pb_unmap(struct pb_buffer *buf)
175 {
176    assert(buf);
177    if(!buf)
178       return;
179    assert(pipe_is_referenced(&buf->reference));
180    buf->vtbl->unmap(buf);
181 }
182 
183 
184 static INLINE void
pb_get_base_buffer(struct pb_buffer * buf,struct pb_buffer ** base_buf,pb_size * offset)185 pb_get_base_buffer( struct pb_buffer *buf,
186 		    struct pb_buffer **base_buf,
187 		    pb_size *offset )
188 {
189    assert(buf);
190    if(!buf) {
191       base_buf = NULL;
192       offset = 0;
193       return;
194    }
195    assert(pipe_is_referenced(&buf->reference));
196    assert(buf->vtbl->get_base_buffer);
197    buf->vtbl->get_base_buffer(buf, base_buf, offset);
198    assert(*base_buf);
199    assert(*offset < (*base_buf)->size);
200 }
201 
202 
203 static INLINE enum pipe_error
pb_validate(struct pb_buffer * buf,struct pb_validate * vl,unsigned flags)204 pb_validate(struct pb_buffer *buf, struct pb_validate *vl, unsigned flags)
205 {
206    assert(buf);
207    if(!buf)
208       return PIPE_ERROR;
209    assert(buf->vtbl->validate);
210    return buf->vtbl->validate(buf, vl, flags);
211 }
212 
213 
214 static INLINE void
pb_fence(struct pb_buffer * buf,struct pipe_fence_handle * fence)215 pb_fence(struct pb_buffer *buf, struct pipe_fence_handle *fence)
216 {
217    assert(buf);
218    if(!buf)
219       return;
220    assert(buf->vtbl->fence);
221    buf->vtbl->fence(buf, fence);
222 }
223 
224 
225 static INLINE void
pb_destroy(struct pb_buffer * buf)226 pb_destroy(struct pb_buffer *buf)
227 {
228    assert(buf);
229    if(!buf)
230       return;
231    assert(!pipe_is_referenced(&buf->reference));
232    buf->vtbl->destroy(buf);
233 }
234 
235 static INLINE void
pb_reference(struct pb_buffer ** dst,struct pb_buffer * src)236 pb_reference(struct pb_buffer **dst,
237              struct pb_buffer *src)
238 {
239    struct pb_buffer *old = *dst;
240 
241    if (pipe_reference(&(*dst)->reference, &src->reference))
242       pb_destroy( old );
243    *dst = src;
244 }
245 
246 
247 /**
248  * Utility function to check whether the provided alignment is consistent with
249  * the requested or not.
250  */
251 static INLINE boolean
pb_check_alignment(pb_size requested,pb_size provided)252 pb_check_alignment(pb_size requested, pb_size provided)
253 {
254    if(!requested)
255       return TRUE;
256    if(requested > provided)
257       return FALSE;
258    if(provided % requested != 0)
259       return FALSE;
260    return TRUE;
261 }
262 
263 
264 /**
265  * Utility function to check whether the provided alignment is consistent with
266  * the requested or not.
267  */
268 static INLINE boolean
pb_check_usage(unsigned requested,unsigned provided)269 pb_check_usage(unsigned requested, unsigned provided)
270 {
271    return (requested & provided) == requested ? TRUE : FALSE;
272 }
273 
274 
275 /**
276  * Malloc-based buffer to store data that can't be used by the graphics
277  * hardware.
278  */
279 struct pb_buffer *
280 pb_malloc_buffer_create(pb_size size,
281                         const struct pb_desc *desc);
282 
283 
284 #ifdef __cplusplus
285 }
286 #endif
287 
288 #endif /*PB_BUFFER_H_*/
289