Add MESA_map_buffer_client_pointer.

Author: Guy1524

api/GL/glext.h

@@ -9503,6 +9503,18 @@ GLAPI void APIENTRY glGetFramebufferParameterivMESA (GLenum target, GLenum pname
 #define GL_FRAMEBUFFER_SWAP_XY_MESA       0x8BBD
 #endif /* GL_MESA_framebuffer_swap_xy */
 
+#ifndef GL_MESA_map_buffer_client_pointer
+#define GL_MESA_map_buffer_client_pointer
+#define GL_BUFFER_CLIENT_POINTER_SIZE_MESA      0x9790
+#define GL_MAP_CLIENT_POINTER_BIT_MESA          0x4000
+typedef void (APIENTRYP PFNGLADDCLIENTPOINTERRANGEMESAPROC) (void *addr, GLsizeiptr size);
+typedef void *(APIENTRYP PFNGLRELEASECLIENTPOINTERRANGEMESAPROC) (GLsizeiptr *size);
+#ifdef GL_GLEXT_PROTOTYPES
+GLAPI void APIENTRY glAddClientPointerRangeMESA(void *addr, GLsizeiptr size);
+GLAPI void *APIENTRY glReleaseClientPointerRangeMESA(GLsizeiptr *size);
+#endif
+#endif /* GL_MESA_map_buffer_client_memory */
+
 #ifndef GL_MESA_pack_invert
 #define GL_MESA_pack_invert 1
 #define GL_PACK_INVERT_MESA               0x8758

extensions/MESA/MESA_map_buffer_client_pointer.txt

@@ -0,0 +1,120 @@
+Name
+
+    MESA_map_buffer_client_pointer
+
+Name Strings
+
+    GL_MESA_map_buffer_client_pointer
+
+Contact
+
+    Derek Lesho <dlesho@codeweavers.com>
+
+Contributors
+
+    Derek Lesho, Codeweavers
+
+Status
+
+    Proposal
+
+Version
+
+    Version 1, February, 2026
+
+Number
+
+    OpenGL Extension 562
+
+Dependencies
+
+    OpenGL 3.0 or ARB_map_buffer_ranged is required.
+
+    This extension is written against the OpenGL 4.6 (Core Profile)
+    Specification.
+
+Overview
+
+    This extension allows the application to specify pointer ranges within
+    which buffers should be mapped.
+
+    This extension is proposed to help the WINE project [https://winehq.org],
+    which implements the 32-bit Windows OpenGL ABI on top of 64-bit Linux,
+    return an address in 32-bit range from Map(Named)Buffer(Range).
+
+IP Status
+
+    None
+
+Issues
+
+    None
+
+New Procedures and Functions
+
+    void AddClientPointerRangeMESA( void *addr, sizeiptr size );
+
+    void *ReleaseClientPointerRangeMESA( sizeiptr *size );
+
+
+New Types
+
+    None
+
+New Tokens
+
+    Accepted by the <access> parameter of MapBufferRange:
+
+        MAP_CLIENT_POINTER_BIT_MESA                0x4000
+
+    Accepted by the <pname> parameter of GetBufferParameter{i|i64}v:
+
+        BUFFER_CLIENT_POINTER_SIZE_MESA            0x9790
+
+
+Additions to Chapter 6 of the OpenGL Core Profile Specification, Version 4.6,
+"Buffer Objects"
+
+    Modify Section 6.3, "Mapping and Unmapping Buffer Data"
+
+    Add to the bulleted list describing flags that modify buffer mappings,
+    p.73.
+
+        * MAP_CLIENT_POINTER_BIT_MESA indicates the mapped buffer pointer must
+          be in an address range provided by in AddClientPointerRangeMESA. If
+          no space is found, OUT_OF_MEMORY is returned.
+
+    Append to Section 6.3 "Mapping and Unmapping Buffer Data", p.78.
+
+        If a buffer is mapped with the MAP_CLIENT_POINTER_BIT_MESA flag, the
+        returned pointer will be in a range provided by the application through
+
+            void AddClientPointerRangeMESA( void *addr, sizeiptr size );
+
+        with <addr> set to the start of a page-aligned address range of size
+        <size> with read and write permissions. The driver will hold this
+        address range for as long as it contains any buffer mappings. While the
+        driver holds the address range, memory access to it in in any manner
+        other than as defined by Map(Named)BufferRange is undefined. To
+        reaquire the pages, first unmap any buffers in the range, call Flush,
+        and thence
+
+            void *ReleaseClientPointerRangeMESA( sizeiptr *size );
+
+        will return the range back to the application, with <size>
+        relaying back the size of the returned range.
+
+
+Errors
+
+    OUT_OF_MEMORY is generated by Map(Named)Buffer if
+    MAP_CLIENT_POINTER_BIT_MESA is included in <access> but no space can be
+    found for a mapping in the ranges provided by AddClientPointerRangeMESA. In
+    this case, the buffer object state value BUFFER_CLIENT_POINTER_SIZE_MESA is
+    set to the size required of a new client pointer range to enable mapping
+    the buffer with MAP_CLIENT_POINTER_BIT_MESA.
+
+Revision History
+
+    Version 1, 2026-2-25 (Derek Lesho)
+        Initial draft.

extensions/registry.py

@@ -3109,6 +3109,12 @@
         'supporters' : { 'MESA' },
         'url' : 'extensions/MESA/MESA_framebuffer_swap_xy.txt',
     },
+    'GL_MESA_map_buffer_client_pointer' : {
+        'number' : 562,
+        'flags' : { 'public' },
+        'supporters' : { 'MESA' },
+        'url' : 'extensions/MESA/MESA_map_buffer_client_pointer.txt',
+    },
     'GL_MESA_pack_invert' : {
         'number' : 300,
         'flags' : { 'public' },

xml/gl.xml

@@ -194,6 +194,7 @@ typedef unsigned int GLhandleARB;
         <enum value="0x0040" name="GL_MAP_PERSISTENT_BIT_EXT" group="MapBufferAccessMask,BufferStorageMask"/>
         <enum value="0x0080" name="GL_MAP_COHERENT_BIT" group="MapBufferAccessMask,BufferStorageMask"/>
         <enum value="0x0080" name="GL_MAP_COHERENT_BIT_EXT" group="MapBufferAccessMask,BufferStorageMask"/>
+        <enum value="0x4000" name="GL_MAP_CLIENT_POINTER_BIT_MESA" group="MapBufferAccessMask"/>
     </enums>
 
     <enums namespace="GL" group="MemoryBarrierMask" type="bitmask">
@@ -7113,6 +7114,10 @@ typedef unsigned int GLhandleARB;
             <unused start="0x9781" end="0x978F" vendor="AMD"/>
     </enums>
 
+    <enums namespace="GL" start="0x9790" end="0x979F" vendor="MESA">
+        <enum value="0x9790" name="GL_BUFFER_CLIENT_POINTER_SIZE_MESA" group="BufferPNameARB"/>
+    </enums>
+
 <!-- Enums reservable for future use. To reserve a new range, allocate one
      or more multiples of 16 starting at the lowest available point in this
      block and note it in a new <enums> block immediately above.
@@ -7122,8 +7127,8 @@ typedef unsigned int GLhandleARB;
      file) File requests in the Khronos Bugzilla, OpenGL project, Registry
      component. -->
 
-    <enums namespace="GL" start="0x9790" end="99999" vendor="ARB" comment="RESERVED FOR FUTURE ALLOCATIONS BY KHRONOS">
-        <unused start="0x9790" end="99999" comment="RESERVED"/>
+    <enums namespace="GL" start="0x97A0" end="99999" vendor="ARB" comment="RESERVED FOR FUTURE ALLOCATIONS BY KHRONOS">
+        <unused start="0x97A0" end="99999" comment="RESERVED"/>
     </enums>
 
 <!-- Historical large block allocations, all unused except (in older days) by IBM -->
@@ -7235,6 +7240,11 @@ typedef unsigned int GLhandleARB;
             <param class="program"><ptype>GLuint</ptype> <name>program</name></param>
             <param len="COMPSIZE(name)">const <ptype>GLchar</ptype> *<name>name</name></param>
         </command>
+        <command>
+            <proto>void <name>glAddClientPointerRangeMESA</name></proto>
+            <param><ptype>GLvoid *</ptype> <name>addr</name></param>
+            <param><ptype>GLsizeiptr</ptype> <name>size</name></param>
+        </command>
         <command>
             <proto>void <name>glAlphaFragmentOp1ATI</name></proto>
             <param group="FragmentOp1ATI"><ptype>GLenum</ptype> <name>op</name></param>
@@ -22470,6 +22480,10 @@ typedef unsigned int GLhandleARB;
             <param len="4">const <ptype>GLdouble</ptype> *<name>equation</name></param>
             <glx type="render" opcode="2071"/>
         </command>
+        <command>
+            <proto>void* <name>glReleaseClientPointerRangeMESA</name></proto>
+            <param><ptype>GLsizeiptr *</ptype> <name>size</name></param>
+        </command>
         <command>
             <proto>void <name>glReleaseShaderCompiler</name></proto>
         </command>
@@ -43662,6 +43676,14 @@ typedef unsigned int GLhandleARB;
                 <enum name="GL_FRAMEBUFFER_SWAP_XY_MESA"/>
             </require>
         </extension>
+        <extension name="GL_MESA_map_buffer_client_pointer" supported="gl">
+            <require>
+                <enum name="GL_MAP_CLIENT_POINTER_BIT_MESA"/>
+                <enum name="GL_BUFFER_CLIENT_POINTER_SIZE_MESA"/>
+                <command name="glAddClientPointerRangeMESA"/>
+                <command name="glReleaseClientPointerRangeMESA"/>
+            </require>
+        </extension>
         <extension name="GL_MESA_pack_invert" supported="gl">
             <require>
                 <enum name="GL_PACK_INVERT_MESA"/>