2 files changed, 70 insertions, 6 deletions

diff --git a/src/gallium/include/pipe/p_inlines.h b/src/gallium/include/pipe/p_inlines.h
index a68b521429..1232c87968 100644
--- a/src/gallium/include/pipe/p_inlines.h
+++ b/src/gallium/include/pipe/p_inlines.h
@@ -60,7 +60,13 @@ pipe_buffer_map(struct pipe_screen *screen,
                 struct pipe_buffer *buf,
                 unsigned usage)
 {
-   return screen->buffer_map(screen, buf, usage);
+   if(screen->buffer_map_range) {
+      unsigned offset = 0;
+      unsigned length = buf->size;
+      return screen->buffer_map_range(screen, buf, offset, length, usage);
+   }
+   else
+      return screen->buffer_map(screen, buf, usage);
 }
 
 static INLINE void
@@ -70,6 +76,35 @@ pipe_buffer_unmap(struct pipe_screen *screen,
    screen->buffer_unmap(screen, buf);
 }
 
+static INLINE void *
+pipe_buffer_map_range(struct pipe_screen *screen,
+                struct pipe_buffer *buf,
+                unsigned offset,
+                unsigned length,
+                unsigned usage)
+{
+   assert(offset < buf->size);
+   assert(offset + length <= buf->size);
+   assert(length);
+   if(screen->buffer_map_range)
+      return screen->buffer_map_range(screen, buf, offset, length, usage);
+   else
+      return screen->buffer_map(screen, buf, usage);
+}
+
+static INLINE void
+pipe_buffer_flush_mapped_range(struct pipe_screen *screen,
+                               struct pipe_buffer *buf,
+                               unsigned offset,
+                               unsigned length)
+{
+   assert(offset < buf->size);
+   assert(offset + length <= buf->size);
+   assert(length);
+   if(screen->buffer_flush_mapped_range)
+      screen->buffer_flush_mapped_range(screen, buf, offset, length);
+}
+
 static INLINE void
 pipe_buffer_write(struct pipe_screen *screen,
                   struct pipe_buffer *buf,
@@ -80,11 +115,13 @@ pipe_buffer_write(struct pipe_screen *screen,
    
    assert(offset < buf->size);
    assert(offset + size <= buf->size);
-   
-   map = pipe_buffer_map(screen, buf, PIPE_BUFFER_USAGE_CPU_WRITE);
+   assert(size);
+
+   map = pipe_buffer_map_range(screen, buf, offset, size, PIPE_BUFFER_USAGE_CPU_WRITE);
    assert(map);
    if(map) {
       memcpy(map + offset, data, size);
+      pipe_buffer_flush_mapped_range(screen, buf, offset, size);
       pipe_buffer_unmap(screen, buf);
    }
 }
@@ -99,8 +136,9 @@ pipe_buffer_read(struct pipe_screen *screen,
    
    assert(offset < buf->size);
    assert(offset + size <= buf->size);
-   
-   map = pipe_buffer_map(screen, buf, PIPE_BUFFER_USAGE_CPU_READ);
+   assert(size);
+
+   map = pipe_buffer_map_range(screen, buf, offset, size, PIPE_BUFFER_USAGE_CPU_READ);
    assert(map);
    if(map) {
       memcpy(data, map + offset, size);
diff --git a/src/gallium/include/pipe/p_screen.h b/src/gallium/include/pipe/p_screen.h
index 3688d58118..ed3a026023 100644
--- a/src/gallium/include/pipe/p_screen.h
+++ b/src/gallium/include/pipe/p_screen.h
@@ -202,9 +202,35 @@ struct pipe_screen {
    void *(*buffer_map)( struct pipe_screen *screen,
 			struct pipe_buffer *buf,
 			unsigned usage );
+   /**
+    * Map a subrange of the buffer data store into the client's address space.
+    *
+    * The returned pointer is always relative to buffer start, regardless of 
+    * the specified range. This is different from the ARB_map_buffer_range
+    * semantics because we don't forbid multiple mappings of the same buffer
+    * (yet).
+    */
+   void *(*buffer_map_range)( struct pipe_screen *screen,
+                              struct pipe_buffer *buf,
+                              unsigned offset,
+                              unsigned length,
+                              unsigned usage);
+
+   /**
+    * Notify a range that was actually written into.
+    * 
+    * The range is relative to the buffer start, regardless of the range 
+    * specified to buffer_map_range. This is different from the 
+    * ARB_map_buffer_range semantics because we don't forbid multiple mappings 
+    * of the same buffer (yet).
+    */
+   void (*buffer_flush_mapped_range)( struct pipe_screen *screen,
+                                      struct pipe_buffer *buf,
+                                      unsigned offset,
+                                      unsigned length);
 
    void (*buffer_unmap)( struct pipe_screen *screen,
-			 struct pipe_buffer *buf );
+                         struct pipe_buffer *buf );
 
    void (*buffer_destroy)( struct pipe_buffer *buf );