/* * Copyright (C) 2014 Intel Corporation * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. */ /** * \file texcompress_bptc.c * GL_ARB_texture_compression_bptc support. */ #include #include "texcompress.h" #include "texcompress_bptc.h" #include "texcompress_bptc_tmp.h" #include "texstore.h" #include "image.h" #include "mtypes.h" static void fetch_bptc_rgb_float(const GLubyte *map, GLint rowStride, GLint i, GLint j, GLfloat *texel, bool is_signed) { const GLubyte *block; block = map + (((rowStride + 3) / 4) * (j / 4) + (i / 4)) * 16; fetch_rgb_float_from_block(block, texel, (i % 4) + (j % 4) * 4, is_signed); } static void fetch_bptc_rgb_signed_float(const GLubyte *map, GLint rowStride, GLint i, GLint j, GLfloat *texel) { fetch_bptc_rgb_float(map, rowStride, i, j, texel, true); } static void fetch_bptc_rgb_unsigned_float(const GLubyte *map, GLint rowStride, GLint i, GLint j, GLfloat *texel) { fetch_bptc_rgb_float(map, rowStride, i, j, texel, false); } static void fetch_bptc_rgba_unorm_bytes(const GLubyte *map, GLint rowStride, GLint i, GLint j, GLubyte *texel) { const GLubyte *block; block = map + (((rowStride + 3) / 4) * (j / 4) + (i / 4)) * 16; fetch_rgba_unorm_from_block(block, texel, (i % 4) + (j % 4) * 4); } static void fetch_bptc_rgba_unorm(const GLubyte *map, GLint rowStride, GLint i, GLint j, GLfloat *texel) { GLubyte texel_bytes[4]; fetch_bptc_rgba_unorm_bytes(map, rowStride, i, j, texel_bytes); texel[RCOMP] = UBYTE_TO_FLOAT(texel_bytes[0]); texel[GCOMP] = UBYTE_TO_FLOAT(texel_bytes[1]); texel[BCOMP] = UBYTE_TO_FLOAT(texel_bytes[2]); texel[ACOMP] = UBYTE_TO_FLOAT(texel_bytes[3]); } static void fetch_bptc_srgb_alpha_unorm(const GLubyte *map, GLint rowStride, GLint i, GLint j, GLfloat *texel) { GLubyte texel_bytes[4]; fetch_bptc_rgba_unorm_bytes(map, rowStride, i, j, texel_bytes); texel[RCOMP] = util_format_srgb_8unorm_to_linear_float(texel_bytes[0]); texel[GCOMP] = util_format_srgb_8unorm_to_linear_float(texel_bytes[1]); texel[BCOMP] = util_format_srgb_8unorm_to_linear_float(texel_bytes[2]); texel[ACOMP] = UBYTE_TO_FLOAT(texel_bytes[3]); } compressed_fetch_func _mesa_get_bptc_fetch_func(mesa_format format) { switch (format) { case MESA_FORMAT_BPTC_RGBA_UNORM: return fetch_bptc_rgba_unorm; case MESA_FORMAT_BPTC_SRGB_ALPHA_UNORM: return fetch_bptc_srgb_alpha_unorm; case MESA_FORMAT_BPTC_RGB_SIGNED_FLOAT: return fetch_bptc_rgb_signed_float; case MESA_FORMAT_BPTC_RGB_UNSIGNED_FLOAT: return fetch_bptc_rgb_unsigned_float; default: return NULL; } } GLboolean _mesa_texstore_bptc_rgba_unorm(TEXSTORE_PARAMS) { const GLubyte *pixels; const GLubyte *tempImage = NULL; int rowstride; if (srcFormat != GL_RGBA || srcType != GL_UNSIGNED_BYTE || ctx->_ImageTransferState || srcPacking->SwapBytes) { /* convert image to RGBA/ubyte */ GLubyte *tempImageSlices[1]; int rgbaRowStride = 4 * srcWidth * sizeof(GLubyte); tempImage = malloc(srcWidth * srcHeight * 4 * sizeof(GLubyte)); if (!tempImage) return GL_FALSE; /* out of memory */ tempImageSlices[0] = (GLubyte *) tempImage; _mesa_texstore(ctx, dims, baseInternalFormat, _mesa_little_endian() ? MESA_FORMAT_R8G8B8A8_UNORM : MESA_FORMAT_A8B8G8R8_UNORM, rgbaRowStride, tempImageSlices, srcWidth, srcHeight, srcDepth, srcFormat, srcType, srcAddr, srcPacking); pixels = tempImage; rowstride = srcWidth * 4; } else { pixels = _mesa_image_address2d(srcPacking, srcAddr, srcWidth, srcHeight, srcFormat, srcType, 0, 0); rowstride = _mesa_image_row_stride(srcPacking, srcWidth, srcFormat, srcType); } compress_rgba_unorm(srcWidth, srcHeight, pixels, rowstride, dstSlices[0], dstRowStride); free((void *) tempImage); return GL_TRUE; } static GLboolean texstore_bptc_rgb_float(TEXSTORE_PARAMS, bool is_signed) { const float *pixels; const float *tempImage = NULL; int rowstride; if (srcFormat != GL_RGB || srcType != GL_FLOAT || ctx->_ImageTransferState || srcPacking->SwapBytes) { /* convert image to RGB/float */ GLfloat *tempImageSlices[1]; int rgbRowStride = 3 * srcWidth * sizeof(GLfloat); tempImage = malloc(srcWidth * srcHeight * 3 * sizeof(GLfloat)); if (!tempImage) return GL_FALSE; /* out of memory */ tempImageSlices[0] = (GLfloat *) tempImage; _mesa_texstore(ctx, dims, baseInternalFormat, MESA_FORMAT_RGB_FLOAT32, rgbRowStride, (GLubyte **)tempImageSlices, srcWidth, srcHeight, srcDepth, srcFormat, srcType, srcAddr, srcPacking); pixels = tempImage; rowstride = srcWidth * sizeof(float) * 3; } else { pixels = _mesa_image_address2d(srcPacking, srcAddr, srcWidth, srcHeight, srcFormat, srcType, 0, 0); rowstride = _mesa_image_row_stride(srcPacking, srcWidth, srcFormat, srcType); } compress_rgb_float(srcWidth, srcHeight, pixels, rowstride, dstSlices[0], dstRowStride, is_signed); free((void *) tempImage); return GL_TRUE; } GLboolean _mesa_texstore_bptc_rgb_signed_float(TEXSTORE_PARAMS) { assert(dstFormat == MESA_FORMAT_BPTC_RGB_SIGNED_FLOAT); return texstore_bptc_rgb_float(ctx, dims, baseInternalFormat, dstFormat, dstRowStride, dstSlices, srcWidth, srcHeight, srcDepth, srcFormat, srcType, srcAddr, srcPacking, true /* signed */); } GLboolean _mesa_texstore_bptc_rgb_unsigned_float(TEXSTORE_PARAMS) { assert(dstFormat == MESA_FORMAT_BPTC_RGB_UNSIGNED_FLOAT); return texstore_bptc_rgb_float(ctx, dims, baseInternalFormat, dstFormat, dstRowStride, dstSlices, srcWidth, srcHeight, srcDepth, srcFormat, srcType, srcAddr, srcPacking, false /* unsigned */); } 49' href='#n149'>149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 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/*
 * Mesa 3-D graphics library
 *
 * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
 * Copyright (C) 2009  VMware, Inc.  All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */


/**
 * \file bufferobj.c
 * \brief Functions for the GL_ARB_vertex/pixel_buffer_object extensions.
 * \author Brian Paul, Ian Romanick
 */

#include <stdbool.h>
#include <inttypes.h>  /* for PRId64 macro */
#include "util/debug.h"
#include "glheader.h"
#include "enums.h"
#include "hash.h"
#include "imports.h"
#include "context.h"
#include "bufferobj.h"
#include "externalobjects.h"
#include "mtypes.h"
#include "teximage.h"
#include "glformats.h"
#include "texstore.h"
#include "transformfeedback.h"
#include "varray.h"
#include "util/u_atomic.h"


/* Debug flags */
/*#define VBO_DEBUG*/
/*#define BOUNDS_CHECK*/


/**
 * We count the number of buffer modification calls to check for
 * inefficient buffer use.  This is the number of such calls before we
 * issue a warning.
 */
#define BUFFER_WARNING_CALL_COUNT 4


/**
 * Helper to warn of possible performance issues, such as frequently
 * updating a buffer created with GL_STATIC_DRAW.  Called via the macro
 * below.
 */
static void
buffer_usage_warning(struct gl_context *ctx, GLuint *id, const char *fmt, ...)
{
   va_list args;

   va_start(args, fmt);
   _mesa_gl_vdebug(ctx, id,
                   MESA_DEBUG_SOURCE_API,
                   MESA_DEBUG_TYPE_PERFORMANCE,
                   MESA_DEBUG_SEVERITY_MEDIUM,
                   fmt, args);
   va_end(args);
}

#define BUFFER_USAGE_WARNING(CTX, FMT, ...) \
   do { \
      static GLuint id = 0; \
      buffer_usage_warning(CTX, &id, FMT, ##__VA_ARGS__); \
   } while (0)


/**
 * Used as a placeholder for buffer objects between glGenBuffers() and
 * glBindBuffer() so that glIsBuffer() can work correctly.
 */
static struct gl_buffer_object DummyBufferObject;


/**
 * Return pointer to address of a buffer object target.
 * \param ctx  the GL context
 * \param target  the buffer object target to be retrieved.
 * \return   pointer to pointer to the buffer object bound to \c target in the
 *           specified context or \c NULL if \c target is invalid.
 */
static inline struct gl_buffer_object **
get_buffer_target(struct gl_context *ctx, GLenum target)
{
   /* Other targets are only supported in desktop OpenGL and OpenGL ES 3.0.
    */
   if (!_mesa_is_desktop_gl(ctx) && !_mesa_is_gles3(ctx)
       && target != GL_ARRAY_BUFFER && target != GL_ELEMENT_ARRAY_BUFFER)
      return NULL;

   switch (target) {
   case GL_ARRAY_BUFFER_ARB:
      return &ctx->Array.ArrayBufferObj;
   case GL_ELEMENT_ARRAY_BUFFER_ARB:
      return &ctx->Array.VAO->IndexBufferObj;
   case GL_PIXEL_PACK_BUFFER_EXT:
      return &ctx->Pack.BufferObj;
   case GL_PIXEL_UNPACK_BUFFER_EXT:
      return &ctx->Unpack.BufferObj;
   case GL_COPY_READ_BUFFER:
      return &ctx->CopyReadBuffer;
   case GL_COPY_WRITE_BUFFER:
      return &ctx->CopyWriteBuffer;
   case GL_QUERY_BUFFER:
      if (_mesa_has_ARB_query_buffer_object(ctx))
         return &ctx->QueryBuffer;
      break;
   case GL_DRAW_INDIRECT_BUFFER:
      if ((_mesa_is_desktop_gl(ctx) && ctx->Extensions.ARB_draw_indirect) ||
           _mesa_is_gles31(ctx)) {
         return &ctx->DrawIndirectBuffer;
      }
      break;
   case GL_PARAMETER_BUFFER_ARB:
      if (_mesa_has_ARB_indirect_parameters(ctx)) {
         return &ctx->ParameterBuffer;
      }
      break;
   case GL_DISPATCH_INDIRECT_BUFFER:
      if (_mesa_has_compute_shaders(ctx)) {
         return &ctx->DispatchIndirectBuffer;
      }
      break;
   case GL_TRANSFORM_FEEDBACK_BUFFER:
      if (ctx->Extensions.EXT_transform_feedback) {
         return &ctx->TransformFeedback.CurrentBuffer;
      }
      break;
   case GL_TEXTURE_BUFFER:
      if (_mesa_has_ARB_texture_buffer_object(ctx) ||
          _mesa_has_OES_texture_buffer(ctx)) {
         return &ctx->Texture.BufferObject;
      }
      break;
   case GL_UNIFORM_BUFFER:
      if (ctx->Extensions.ARB_uniform_buffer_object) {
         return &ctx->UniformBuffer;
      }
      break;
   case GL_SHADER_STORAGE_BUFFER:
      if (ctx->Extensions.ARB_shader_storage_buffer_object) {
         return &ctx->ShaderStorageBuffer;
      }
      break;
   case GL_ATOMIC_COUNTER_BUFFER:
      if (ctx->Extensions.ARB_shader_atomic_counters) {
         return &ctx->AtomicBuffer;
      }
      break;
   case GL_EXTERNAL_VIRTUAL_MEMORY_BUFFER_AMD:
      if (ctx->Extensions.AMD_pinned_memory) {
         return &ctx->ExternalVirtualMemoryBuffer;
      }
      break;
   default:
      return NULL;
   }
   return NULL;
}


/**
 * Get the buffer object bound to the specified target in a GL context.
 * \param ctx  the GL context
 * \param target  the buffer object target to be retrieved.
 * \param error  the GL error to record if target is illegal.
 * \return   pointer to the buffer object bound to \c target in the
 *           specified context or \c NULL if \c target is invalid.
 */
static inline struct gl_buffer_object *
get_buffer(struct gl_context *ctx, const char *func, GLenum target,
           GLenum error)
{
   struct gl_buffer_object **bufObj = get_buffer_target(ctx, target);

   if (!bufObj) {
      _mesa_error(ctx, GL_INVALID_ENUM, "%s(target)", func);
      return NULL;
   }

   if (!_mesa_is_bufferobj(*bufObj)) {
      _mesa_error(ctx, error, "%s(no buffer bound)", func);
      return NULL;
   }

   return *bufObj;
}


/**
 * Convert a GLbitfield describing the mapped buffer access flags
 * into one of GL_READ_WRITE, GL_READ_ONLY, or GL_WRITE_ONLY.
 */
static GLenum
simplified_access_mode(struct gl_context *ctx, GLbitfield access)
{
   const GLbitfield rwFlags = GL_MAP_READ_BIT | GL_MAP_WRITE_BIT;
   if ((access & rwFlags) == rwFlags)
      return GL_READ_WRITE;
   if ((access & GL_MAP_READ_BIT) == GL_MAP_READ_BIT)
      return GL_READ_ONLY;
   if ((access & GL_MAP_WRITE_BIT) == GL_MAP_WRITE_BIT)
      return GL_WRITE_ONLY;

   /* Otherwise, AccessFlags is zero (the default state).
    *
    * Table 2.6 on page 31 (page 44 of the PDF) of the OpenGL 1.5 spec says:
    *
    * Name           Type  Initial Value  Legal Values
    * ...            ...   ...            ...
    * BUFFER_ACCESS  enum  READ_WRITE     READ_ONLY, WRITE_ONLY
    *                                     READ_WRITE
    *
    * However, table 6.8 in the GL_OES_mapbuffer extension says:
    *
    * Get Value         Type Get Command          Value          Description
    * ---------         ---- -----------          -----          -----------
    * BUFFER_ACCESS_OES Z1   GetBufferParameteriv WRITE_ONLY_OES buffer map flag
    *
    * The difference is because GL_OES_mapbuffer only supports mapping buffers
    * write-only.
    */
   assert(access == 0);

   return _mesa_is_gles(ctx) ? GL_WRITE_ONLY : GL_READ_WRITE;
}


/**
 * Test if the buffer is mapped, and if so, if the mapped range overlaps the
 * given range.
 * The regions do not overlap if and only if the end of the given
 * region is before the mapped region or the start of the given region
 * is after the mapped region.
 *
 * \param obj     Buffer object target on which to operate.
 * \param offset  Offset of the first byte of the subdata range.
 * \param size    Size, in bytes, of the subdata range.
 * \return   true if ranges overlap, false otherwise
 *
 */
static bool
bufferobj_range_mapped(const struct gl_buffer_object *obj,
                       GLintptr offset, GLsizeiptr size)
{
   if (_mesa_bufferobj_mapped(obj, MAP_USER)) {
      const GLintptr end = offset + size;
      const GLintptr mapEnd = obj->Mappings[MAP_USER].Offset +
                              obj->Mappings[MAP_USER].Length;

      if (!(end <= obj->Mappings[MAP_USER].Offset || offset >= mapEnd)) {
         return true;
      }
   }
   return false;
}


/**
 * Tests the subdata range parameters and sets the GL error code for
 * \c glBufferSubDataARB, \c glGetBufferSubDataARB and
 * \c glClearBufferSubData.
 *
 * \param ctx     GL context.
 * \param bufObj  The buffer object.
 * \param offset  Offset of the first byte of the subdata range.
 * \param size    Size, in bytes, of the subdata range.
 * \param mappedRange  If true, checks if an overlapping range is mapped.
 *                     If false, checks if buffer is mapped.
 * \param caller  Name of calling function for recording errors.
 * \return   false if error, true otherwise
 *
 * \sa glBufferSubDataARB, glGetBufferSubDataARB, glClearBufferSubData
 */
static bool
buffer_object_subdata_range_good(struct gl_context *ctx,
                                 const struct gl_buffer_object *bufObj,
                                 GLintptr offset, GLsizeiptr size,
                                 bool mappedRange, const char *caller)
{
   if (size < 0) {
      _mesa_error(ctx, GL_INVALID_VALUE, "%s(size < 0)", caller);
      return false;
   }

   if (offset < 0) {
      _mesa_error(ctx, GL_INVALID_VALUE, "%s(offset < 0)", caller);
      return false;
   }

   if (offset + size > bufObj->Size) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(offset %lu + size %lu > buffer size %lu)", caller,
                  (unsigned long) offset,
                  (unsigned long) size,
                  (unsigned long) bufObj->Size);
      return false;
   }

   if (bufObj->Mappings[MAP_USER].AccessFlags & GL_MAP_PERSISTENT_BIT)
      return true;

   if (mappedRange) {
      if (bufferobj_range_mapped(bufObj, offset, size)) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "%s(range is mapped without persistent bit)",
                     caller);
         return false;
      }
   }
   else {
      if (_mesa_bufferobj_mapped(bufObj, MAP_USER)) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "%s(buffer is mapped without persistent bit)",
                     caller);
         return false;
      }
   }

   return true;
}


/**
 * Test the format and type parameters and set the GL error code for
 * \c glClearBufferData and \c glClearBufferSubData.
 *
 * \param ctx             GL context.
 * \param internalformat  Format to which the data is to be converted.
 * \param format          Format of the supplied data.
 * \param type            Type of the supplied data.
 * \param caller          Name of calling function for recording errors.
 * \return   If internalformat, format and type are legal the mesa_format
 *           corresponding to internalformat, otherwise MESA_FORMAT_NONE.
 *
 * \sa glClearBufferData and glClearBufferSubData
 */
static mesa_format
validate_clear_buffer_format(struct gl_context *ctx,
                             GLenum internalformat,
                             GLenum format, GLenum type,
                             const char *caller)
{
   mesa_format mesaFormat;
   GLenum errorFormatType;

   mesaFormat = _mesa_validate_texbuffer_format(ctx, internalformat);
   if (mesaFormat == MESA_FORMAT_NONE) {
      _mesa_error(ctx, GL_INVALID_ENUM,
                  "%s(invalid internalformat)", caller);
      return MESA_FORMAT_NONE;
   }

   /* NOTE: not mentioned in ARB_clear_buffer_object but according to
    * EXT_texture_integer there is no conversion between integer and
    * non-integer formats
   */
   if (_mesa_is_enum_format_signed_int(format) !=
       _mesa_is_format_integer_color(mesaFormat)) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(integer vs non-integer)", caller);
      return MESA_FORMAT_NONE;
   }

   if (!_mesa_is_color_format(format)) {
      _mesa_error(ctx, GL_INVALID_ENUM,
                  "%s(format is not a color format)", caller);
      return MESA_FORMAT_NONE;
   }

   errorFormatType = _mesa_error_check_format_and_type(ctx, format, type);
   if (errorFormatType != GL_NO_ERROR) {
      _mesa_error(ctx, GL_INVALID_ENUM,
                  "%s(invalid format or type)", caller);
      return MESA_FORMAT_NONE;
   }

   return mesaFormat;
}


/**
 * Convert user-specified clear value to the specified internal format.
 *
 * \param ctx             GL context.
 * \param internalformat  Format to which the data is converted.
 * \param clearValue      Points to the converted clear value.
 * \param format          Format of the supplied data.
 * \param type            Type of the supplied data.
 * \param data            Data which is to be converted to internalformat.
 * \param caller          Name of calling function for recording errors.
 * \return   true if data could be converted, false otherwise.
 *
 * \sa glClearBufferData, glClearBufferSubData
 */
static bool
convert_clear_buffer_data(struct gl_context *ctx,
                          mesa_format internalformat,
                          GLubyte *clearValue, GLenum format, GLenum type,
                          const GLvoid *data, const char *caller)
{
   GLenum internalformatBase = _mesa_get_format_base_format(internalformat);

   if (_mesa_texstore(ctx, 1, internalformatBase, internalformat,
                      0, &clearValue, 1, 1, 1,
                      format, type, data, &ctx->Unpack)) {
      return true;
   }
   else {
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "%s", caller);
      return false;
   }
}


/**
 * Allocate and initialize a new buffer object.
 *
 * Default callback for the \c dd_function_table::NewBufferObject() hook.
 */
static struct gl_buffer_object *
_mesa_new_buffer_object(struct gl_context *ctx, GLuint name)
{
   struct gl_buffer_object *obj = MALLOC_STRUCT(gl_buffer_object);
   if (!obj)
      return NULL;

   _mesa_initialize_buffer_object(ctx, obj, name);
   return obj;
}


/**
 * Delete a buffer object.
 *
 * Default callback for the \c dd_function_table::DeleteBuffer() hook.
 */
void
_mesa_delete_buffer_object(struct gl_context *ctx,
                           struct gl_buffer_object *bufObj)
{
   (void) ctx;

   vbo_delete_minmax_cache(bufObj);
   _mesa_align_free(bufObj->Data);

   /* assign strange values here to help w/ debugging */
   bufObj->RefCount = -1000;
   bufObj->Name = ~0;

   simple_mtx_destroy(&bufObj->MinMaxCacheMutex);
   free(bufObj->Label);
   free(bufObj);
}



/**
 * Set ptr to bufObj w/ reference counting.
 * This is normally only called from the _mesa_reference_buffer_object() macro
 * when there's a real pointer change.
 */
void
_mesa_reference_buffer_object_(struct gl_context *ctx,
                               struct gl_buffer_object **ptr,
                               struct gl_buffer_object *bufObj)
{
   if (*ptr) {
      /* Unreference the old buffer */
      struct gl_buffer_object *oldObj = *ptr;

      if (p_atomic_dec_zero(&oldObj->RefCount)) {
	 assert(ctx->Driver.DeleteBuffer);
         ctx->Driver.DeleteBuffer(ctx, oldObj);
      }

      *ptr = NULL;
   }
   assert(!*ptr);

   if (bufObj) {
      /* reference new buffer */
      p_atomic_inc(&bufObj->RefCount);
      *ptr = bufObj;
   }
}


/**
 * Get the value of MESA_NO_MINMAX_CACHE.
 */
static bool
get_no_minmax_cache()
{
   static bool read = false;
   static bool disable = false;

   if (!read) {
      disable = env_var_as_boolean("MESA_NO_MINMAX_CACHE", false);
      read = true;
   }

   return disable;
}


/**
 * Initialize a buffer object to default values.
 */
void
_mesa_initialize_buffer_object(struct gl_context *ctx,
                               struct gl_buffer_object *obj,
                               GLuint name)
{
   memset(obj, 0, sizeof(struct gl_buffer_object));
   obj->RefCount = 1;
   obj->Name = name;
   obj->Usage = GL_STATIC_DRAW_ARB;

   simple_mtx_init(&obj->MinMaxCacheMutex, mtx_plain);
   if (get_no_minmax_cache())
      obj->UsageHistory |= USAGE_DISABLE_MINMAX_CACHE;
}



/**
 * Callback called from _mesa_HashWalk()
 */
static void
count_buffer_size(GLuint key, void *data, void *userData)
{
   const struct gl_buffer_object *bufObj =
      (const struct gl_buffer_object *) data;
   GLuint *total = (GLuint *) userData;

   (void) key;
   *total = *total + bufObj->Size;
}


/**
 * Compute total size (in bytes) of all buffer objects for the given context.
 * For debugging purposes.
 */
GLuint
_mesa_total_buffer_object_memory(struct gl_context *ctx)
{
   GLuint total = 0;

   _mesa_HashWalk(ctx->Shared->BufferObjects, count_buffer_size, &total);

   return total;
}


/**
 * Allocate space for and store data in a buffer object.  Any data that was
 * previously stored in the buffer object is lost.  If \c data is \c NULL,
 * memory will be allocated, but no copy will occur.
 *
 * This is the default callback for \c dd_function_table::BufferData()
 * Note that all GL error checking will have been done already.
 *
 * \param ctx     GL context.
 * \param target  Buffer object target on which to operate.
 * \param size    Size, in bytes, of the new data store.
 * \param data    Pointer to the data to store in the buffer object.  This
 *                pointer may be \c NULL.
 * \param usage   Hints about how the data will be used.
 * \param bufObj  Object to be used.
 *
 * \return GL_TRUE for success, GL_FALSE for failure
 * \sa glBufferDataARB, dd_function_table::BufferData.
 */
static GLboolean
buffer_data_fallback(struct gl_context *ctx, GLenum target, GLsizeiptr size,
                     const GLvoid *data, GLenum usage, GLenum storageFlags,
                     struct gl_buffer_object *bufObj)
{
   void * new_data;

   (void) target;

   _mesa_align_free( bufObj->Data );

   new_data = _mesa_align_malloc( size, ctx->Const.MinMapBufferAlignment );
   if (new_data) {
      bufObj->Data = (GLubyte *) new_data;
      bufObj->Size = size;
      bufObj->Usage = usage;
      bufObj->StorageFlags = storageFlags;

      if (data) {
	 memcpy( bufObj->Data, data, size );
      }

      return GL_TRUE;
   }
   else {
      return GL_FALSE;
   }
}


/**
 * Replace data in a subrange of buffer object.  If the data range
 * specified by \c size + \c offset extends beyond the end of the buffer or
 * if \c data is \c NULL, no copy is performed.
 *
 * This is the default callback for \c dd_function_table::BufferSubData()
 * Note that all GL error checking will have been done already.
 *
 * \param ctx     GL context.
 * \param offset  Offset of the first byte to be modified.
 * \param size    Size, in bytes, of the data range.
 * \param data    Pointer to the data to store in the buffer object.
 * \param bufObj  Object to be used.
 *
 * \sa glBufferSubDataARB, dd_function_table::BufferSubData.
 */
static void
buffer_sub_data_fallback(struct gl_context *ctx, GLintptr offset,
                         GLsizeiptr size, const GLvoid *data,
                         struct gl_buffer_object *bufObj)
{
   (void) ctx;

   /* this should have been caught in _mesa_BufferSubData() */
   assert(size + offset <= bufObj->Size);

   if (bufObj->Data) {
      memcpy( (GLubyte *) bufObj->Data + offset, data, size );
   }
}


/**
 * Retrieve data from a subrange of buffer object.  If the data range
 * specified by \c size + \c offset extends beyond the end of the buffer or
 * if \c data is \c NULL, no copy is performed.
 *
 * This is the default callback for \c dd_function_table::GetBufferSubData()
 * Note that all GL error checking will have been done already.
 *
 * \param ctx     GL context.
 * \param target  Buffer object target on which to operate.
 * \param offset  Offset of the first byte to be fetched.
 * \param size    Size, in bytes, of the data range.
 * \param data    Destination for data
 * \param bufObj  Object to be used.
 *
 * \sa glBufferGetSubDataARB, dd_function_table::GetBufferSubData.
 */
static void
buffer_get_subdata(struct gl_context *ctx, GLintptrARB offset,
                   GLsizeiptrARB size, GLvoid *data,
                   struct gl_buffer_object *bufObj )
{
   (void) ctx;

   if (bufObj->Data && ((GLsizeiptrARB) (size + offset) <= bufObj->Size)) {
      memcpy( data, (GLubyte *) bufObj->Data + offset, size );
   }
}


/**
 * Clear a subrange of the buffer object with copies of the supplied data.
 * If data is NULL the buffer is filled with zeros.
 *
 * This is the default callback for \c dd_function_table::ClearBufferSubData()
 * Note that all GL error checking will have been done already.
 *
 * \param ctx             GL context.
 * \param offset          Offset of the first byte to be cleared.
 * \param size            Size, in bytes, of the to be cleared range.
 * \param clearValue      Source of the data.
 * \param clearValueSize  Size, in bytes, of the supplied data.
 * \param bufObj          Object to be cleared.
 *
 * \sa glClearBufferSubData, glClearBufferData and
 * dd_function_table::ClearBufferSubData.
 */
void
_mesa_ClearBufferSubData_sw(struct gl_context *ctx,
                            GLintptr offset, GLsizeiptr size,
                            const GLvoid *clearValue,
                            GLsizeiptr clearValueSize,
                            struct gl_buffer_object *bufObj)
{
   GLsizeiptr i;
   GLubyte *dest;

   assert(ctx->Driver.MapBufferRange);
   dest = ctx->Driver.MapBufferRange(ctx, offset, size,
                                     GL_MAP_WRITE_BIT |
                                     GL_MAP_INVALIDATE_RANGE_BIT,
                                     bufObj, MAP_INTERNAL);

   if (!dest) {
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glClearBuffer[Sub]Data");
      return;
   }

   if (clearValue == NULL) {
      /* Clear with zeros, per the spec */
      memset(dest, 0, size);
      ctx->Driver.UnmapBuffer(ctx, bufObj, MAP_INTERNAL);
      return;
   }

   for (i = 0; i < size/clearValueSize; ++i) {
      memcpy(dest, clearValue, clearValueSize);
      dest += clearValueSize;
   }

   ctx->Driver.UnmapBuffer(ctx, bufObj, MAP_INTERNAL);
}


/**
 * Default fallback for \c dd_function_table::MapBufferRange().
 * Called via glMapBufferRange().
 */
static void *
map_buffer_range_fallback(struct gl_context *ctx, GLintptr offset,
                          GLsizeiptr length, GLbitfield access,
                          struct gl_buffer_object *bufObj,
                          gl_map_buffer_index index)
{
   (void) ctx;
   assert(!_mesa_bufferobj_mapped(bufObj, index));
   /* Just return a direct pointer to the data */
   bufObj->Mappings[index].Pointer = bufObj->Data + offset;
   bufObj->Mappings[index].Length = length;
   bufObj->Mappings[index].Offset = offset;
   bufObj->Mappings[index].AccessFlags = access;
   return bufObj->Mappings[index].Pointer;
}


/**
 * Default fallback for \c dd_function_table::FlushMappedBufferRange().
 * Called via glFlushMappedBufferRange().
 */
static void
flush_mapped_buffer_range_fallback(struct gl_context *ctx,
                                   GLintptr offset, GLsizeiptr length,
                                   struct gl_buffer_object *obj,
                                   gl_map_buffer_index index)
{
   (void) ctx;
   (void) offset;
   (void) length;
   (void) obj;
   (void) index;
   /* no-op */
}


/**
 * Default callback for \c dd_function_table::UnmapBuffer().
 *
 * The input parameters will have been already tested for errors.
 *
 * \sa glUnmapBufferARB, dd_function_table::UnmapBuffer
 */
static GLboolean
unmap_buffer_fallback(struct gl_context *ctx, struct gl_buffer_object *bufObj,
                      gl_map_buffer_index index)
{
   (void) ctx;
   /* XXX we might assert here that bufObj->Pointer is non-null */
   bufObj->Mappings[index].Pointer = NULL;
   bufObj->Mappings[index].Length = 0;
   bufObj->Mappings[index].Offset = 0;
   bufObj->Mappings[index].AccessFlags = 0x0;
   return GL_TRUE;
}


/**
 * Default fallback for \c dd_function_table::CopyBufferSubData().
 * Called via glCopyBufferSubData().
 */
static void
copy_buffer_sub_data_fallback(struct gl_context *ctx,
                              struct gl_buffer_object *src,
                              struct gl_buffer_object *dst,
                              GLintptr readOffset, GLintptr writeOffset,
                              GLsizeiptr size)
{
   GLubyte *srcPtr, *dstPtr;

   if (src == dst) {
      srcPtr = dstPtr = ctx->Driver.MapBufferRange(ctx, 0, src->Size,
						   GL_MAP_READ_BIT |
						   GL_MAP_WRITE_BIT, src,
                                                   MAP_INTERNAL);

      if (!srcPtr)
	 return;

      srcPtr += readOffset;
      dstPtr += writeOffset;
   } else {
      srcPtr = ctx->Driver.MapBufferRange(ctx, readOffset, size,
					  GL_MAP_READ_BIT, src,
                                          MAP_INTERNAL);
      dstPtr = ctx->Driver.MapBufferRange(ctx, writeOffset, size,
					  (GL_MAP_WRITE_BIT |
					   GL_MAP_INVALIDATE_RANGE_BIT), dst,
                                          MAP_INTERNAL);
   }

   /* Note: the src and dst regions will never overlap.  Trying to do so
    * would generate GL_INVALID_VALUE earlier.
    */
   if (srcPtr && dstPtr)
      memcpy(dstPtr, srcPtr, size);

   ctx->Driver.UnmapBuffer(ctx, src, MAP_INTERNAL);
   if (dst != src)
      ctx->Driver.UnmapBuffer(ctx, dst, MAP_INTERNAL);
}



/**
 * Initialize the state associated with buffer objects
 */
void
_mesa_init_buffer_objects( struct gl_context *ctx )
{
   GLuint i;

   memset(&DummyBufferObject, 0, sizeof(DummyBufferObject));
   simple_mtx_init(&DummyBufferObject.MinMaxCacheMutex, mtx_plain);
   DummyBufferObject.RefCount = 1000*1000*1000; /* never delete */

   _mesa_reference_buffer_object(ctx, &ctx->Array.ArrayBufferObj,
                                 ctx->Shared->NullBufferObj);

   _mesa_reference_buffer_object(ctx, &ctx->CopyReadBuffer,
                                 ctx->Shared->NullBufferObj);
   _mesa_reference_buffer_object(ctx, &ctx->CopyWriteBuffer,
                                 ctx->Shared->NullBufferObj);

   _mesa_reference_buffer_object(ctx, &ctx->UniformBuffer,
				 ctx->Shared->NullBufferObj);

   _mesa_reference_buffer_object(ctx, &ctx->ShaderStorageBuffer,
                                 ctx->Shared->NullBufferObj);

   _mesa_reference_buffer_object(ctx, &ctx->AtomicBuffer,
				 ctx->Shared->NullBufferObj);

   _mesa_reference_buffer_object(ctx, &ctx->DrawIndirectBuffer,
				 ctx->Shared->NullBufferObj);

   _mesa_reference_buffer_object(ctx, &ctx->ParameterBuffer,
				 ctx->Shared->NullBufferObj);

   _mesa_reference_buffer_object(ctx, &ctx->DispatchIndirectBuffer,
				 ctx->Shared->NullBufferObj);

   _mesa_reference_buffer_object(ctx, &ctx->QueryBuffer,
                                 ctx->Shared->NullBufferObj);

   for (i = 0; i < MAX_COMBINED_UNIFORM_BUFFERS; i++) {
      _mesa_reference_buffer_object(ctx,
				    &ctx->UniformBufferBindings[i].BufferObject,
				    ctx->Shared->NullBufferObj);
      ctx->UniformBufferBindings[i].Offset = -1;
      ctx->UniformBufferBindings[i].Size = -1;
   }

   for (i = 0; i < MAX_COMBINED_SHADER_STORAGE_BUFFERS; i++) {
      _mesa_reference_buffer_object(ctx,
                                    &ctx->ShaderStorageBufferBindings[i].BufferObject,
                                    ctx->Shared->NullBufferObj);
      ctx->ShaderStorageBufferBindings[i].Offset = -1;
      ctx->ShaderStorageBufferBindings[i].Size = -1;
   }

   for (i = 0; i < MAX_COMBINED_ATOMIC_BUFFERS; i++) {
      _mesa_reference_buffer_object(ctx,
				    &ctx->AtomicBufferBindings[i].BufferObject,
				    ctx->Shared->NullBufferObj);
      ctx->AtomicBufferBindings[i].Offset = 0;
      ctx->AtomicBufferBindings[i].Size = 0;
   }
}


void
_mesa_free_buffer_objects( struct gl_context *ctx )
{
   GLuint i;

   _mesa_reference_buffer_object(ctx, &ctx->Array.ArrayBufferObj, NULL);

   _mesa_reference_buffer_object(ctx, &ctx->CopyReadBuffer, NULL);
   _mesa_reference_buffer_object(ctx, &ctx->CopyWriteBuffer, NULL);

   _mesa_reference_buffer_object(ctx, &ctx->UniformBuffer, NULL);

   _mesa_reference_buffer_object(ctx, &ctx->ShaderStorageBuffer, NULL);

   _mesa_reference_buffer_object(ctx, &ctx->AtomicBuffer, NULL);

   _mesa_reference_buffer_object(ctx, &ctx->DrawIndirectBuffer, NULL);

   _mesa_reference_buffer_object(ctx, &ctx->ParameterBuffer, NULL);

   _mesa_reference_buffer_object(ctx, &ctx->DispatchIndirectBuffer, NULL);

   _mesa_reference_buffer_object(ctx, &ctx->QueryBuffer, NULL);

   for (i = 0; i < MAX_COMBINED_UNIFORM_BUFFERS; i++) {
      _mesa_reference_buffer_object(ctx,
				    &ctx->UniformBufferBindings[i].BufferObject,
				    NULL);
   }

   for (i = 0; i < MAX_COMBINED_SHADER_STORAGE_BUFFERS; i++) {
      _mesa_reference_buffer_object(ctx,
                                    &ctx->ShaderStorageBufferBindings[i].BufferObject,
                                    NULL);
   }

   for (i = 0; i < MAX_COMBINED_ATOMIC_BUFFERS; i++) {
      _mesa_reference_buffer_object(ctx,
				    &ctx->AtomicBufferBindings[i].BufferObject,
				    NULL);
   }

}

bool
_mesa_handle_bind_buffer_gen(struct gl_context *ctx,
                             GLuint buffer,
                             struct gl_buffer_object **buf_handle,
                             const char *caller)
{
   struct gl_buffer_object *buf = *buf_handle;

   if (!buf && (ctx->API == API_OPENGL_CORE)) {
      _mesa_error(ctx, GL_INVALID_OPERATION, "%s(non-gen name)", caller);
      return false;
   }

   if (!buf || buf == &DummyBufferObject) {
      /* If this is a new buffer object id, or one which was generated but
       * never used before, allocate a buffer object now.
       */
      buf = ctx->Driver.NewBufferObject(ctx, buffer);
      if (!buf) {
	 _mesa_error(ctx, GL_OUT_OF_MEMORY, "%s", caller);
	 return false;
      }
      _mesa_HashInsert(ctx->Shared->BufferObjects, buffer, buf);
      *buf_handle = buf;
   }

   return true;
}

/**
 * Bind the specified target to buffer for the specified context.
 * Called by glBindBuffer() and other functions.
 */
static void
bind_buffer_object(struct gl_context *ctx,
                   struct gl_buffer_object **bindTarget, GLuint buffer)
{
   struct gl_buffer_object *oldBufObj;
   struct gl_buffer_object *newBufObj = NULL;

   assert(bindTarget);

   /* Get pointer to old buffer object (to be unbound) */
   oldBufObj = *bindTarget;
   if (oldBufObj && oldBufObj->Name == buffer && !oldBufObj->DeletePending)
      return;   /* rebinding the same buffer object- no change */

   /*
    * Get pointer to new buffer object (newBufObj)
    */
   if (buffer == 0) {
      /* The spec says there's not a buffer object named 0, but we use
       * one internally because it simplifies things.
       */
      newBufObj = ctx->Shared->NullBufferObj;
   }
   else {
      /* non-default buffer object */
      newBufObj = _mesa_lookup_bufferobj(ctx, buffer);
      if (!_mesa_handle_bind_buffer_gen(ctx, buffer,
                                        &newBufObj, "glBindBuffer"))
         return;
   }

   /* record usage history */
   if (bindTarget == &ctx->Pack.BufferObj) {
      newBufObj->UsageHistory |= USAGE_PIXEL_PACK_BUFFER;
   }

   /* bind new buffer */
   _mesa_reference_buffer_object(ctx, bindTarget, newBufObj);
}


/**
 * Update the default buffer objects in the given context to reference those
 * specified in the shared state and release those referencing the old
 * shared state.
 */
void
_mesa_update_default_objects_buffer_objects(struct gl_context *ctx)
{
   /* Bind the NullBufferObj to remove references to those
    * in the shared context hash table.
    */
   bind_buffer_object(ctx, &ctx->Array.ArrayBufferObj, 0);
   bind_buffer_object(ctx, &ctx->Array.VAO->IndexBufferObj, 0);
   bind_buffer_object(ctx, &ctx->Pack.BufferObj, 0);
   bind_buffer_object(ctx, &ctx->Unpack.BufferObj, 0);
}



/**
 * Return the gl_buffer_object for the given ID.
 * Always return NULL for ID 0.
 */
struct gl_buffer_object *
_mesa_lookup_bufferobj(struct gl_context *ctx, GLuint buffer)
{
   if (buffer == 0)
      return NULL;
   else
      return (struct gl_buffer_object *)
         _mesa_HashLookup(ctx->Shared->BufferObjects, buffer);
}


struct gl_buffer_object *
_mesa_lookup_bufferobj_locked(struct gl_context *ctx, GLuint buffer)
{
   if (buffer == 0)
      return NULL;
   else
      return (struct gl_buffer_object *)
         _mesa_HashLookupLocked(ctx->Shared->BufferObjects, buffer);
}

/**
 * A convenience function for direct state access functions that throws
 * GL_INVALID_OPERATION if buffer is not the name of an existing
 * buffer object.
 */
struct gl_buffer_object *
_mesa_lookup_bufferobj_err(struct gl_context *ctx, GLuint buffer,
                           const char *caller)
{
   struct gl_buffer_object *bufObj;

   bufObj = _mesa_lookup_bufferobj(ctx, buffer);
   if (!bufObj || bufObj == &DummyBufferObject) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(non-existent buffer object %u)", caller, buffer);
      return NULL;
   }

   return bufObj;
}


/**
 * Look up a buffer object for a multi-bind function.
 *
 * Unlike _mesa_lookup_bufferobj(), this function also takes care
 * of generating an error if the buffer ID is not zero or the name
 * of an existing buffer object.
 *
 * If the buffer ID refers to an existing buffer object, a pointer
 * to the buffer object is returned.  If the ID is zero, a pointer
 * to the shared NullBufferObj is returned.  If the ID is not zero
 * and does not refer to a valid buffer object, this function
 * returns NULL.
 *
 * This function assumes that the caller has already locked the
 * hash table mutex by calling
 * _mesa_HashLockMutex(ctx->Shared->BufferObjects).
 */
struct gl_buffer_object *
_mesa_multi_bind_lookup_bufferobj(struct gl_context *ctx,
                                  const GLuint *buffers,
                                  GLuint index, const char *caller)
{
   struct gl_buffer_object *bufObj;

   if (buffers[index] != 0) {
      bufObj = _mesa_lookup_bufferobj_locked(ctx, buffers[index]);

      /* The multi-bind functions don't create the buffer objects
         when they don't exist. */
      if (bufObj == &DummyBufferObject)
         bufObj = NULL;
   } else
      bufObj = ctx->Shared->NullBufferObj;

   if (!bufObj) {
      /* The ARB_multi_bind spec says:
       *
       *    "An INVALID_OPERATION error is generated if any value
       *     in <buffers> is not zero or the name of an existing
       *     buffer object (per binding)."
       */
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(buffers[%u]=%u is not zero or the name "
                  "of an existing buffer object)",
                  caller, index, buffers[index]);
   }

   return bufObj;
}


/**
 * If *ptr points to obj, set ptr = the Null/default buffer object.
 * This is a helper for buffer object deletion.
 * The GL spec says that deleting a buffer object causes it to get
 * unbound from all arrays in the current context.
 */
static void
unbind(struct gl_context *ctx,
       struct gl_vertex_array_object *vao, unsigned index,
       struct gl_buffer_object *obj)
{
   if (vao->BufferBinding[index].BufferObj == obj) {
      _mesa_bind_vertex_buffer(ctx, vao, index, ctx->Shared->NullBufferObj,
                               vao->BufferBinding[index].Offset,
                               vao->BufferBinding[index].Stride);
   }
}


/**
 * Plug default/fallback buffer object functions into the device
 * driver hooks.
 */
void
_mesa_init_buffer_object_functions(struct dd_function_table *driver)
{
   /* GL_ARB_vertex/pixel_buffer_object */
   driver->NewBufferObject = _mesa_new_buffer_object;
   driver->DeleteBuffer = _mesa_delete_buffer_object;
   driver->BufferData = buffer_data_fallback;
   driver->BufferSubData = buffer_sub_data_fallback;
   driver->GetBufferSubData = buffer_get_subdata;
   driver->UnmapBuffer = unmap_buffer_fallback;

   /* GL_ARB_clear_buffer_object */
   driver->ClearBufferSubData = _mesa_ClearBufferSubData_sw;

   /* GL_ARB_map_buffer_range */
   driver->MapBufferRange = map_buffer_range_fallback;
   driver->FlushMappedBufferRange = flush_mapped_buffer_range_fallback;

   /* GL_ARB_copy_buffer */
   driver->CopyBufferSubData = copy_buffer_sub_data_fallback;
}


void
_mesa_buffer_unmap_all_mappings(struct gl_context *ctx,
                                struct gl_buffer_object *bufObj)
{
   for (int i = 0; i < MAP_COUNT; i++) {
      if (_mesa_bufferobj_mapped(bufObj, i)) {
         ctx->Driver.UnmapBuffer(ctx, bufObj, i);
         assert(bufObj->Mappings[i].Pointer == NULL);
         bufObj->Mappings[i].AccessFlags = 0;
      }
   }
}


/**********************************************************************/
/* API Functions                                                      */
/**********************************************************************/

void GLAPIENTRY
_mesa_BindBuffer_no_error(GLenum target, GLuint buffer)
{
   GET_CURRENT_CONTEXT(ctx);

   struct gl_buffer_object **bindTarget = get_buffer_target(ctx, target);
   bind_buffer_object(ctx, bindTarget, buffer);
}


void GLAPIENTRY
_mesa_BindBuffer(GLenum target, GLuint buffer)
{
   GET_CURRENT_CONTEXT(ctx);

   if (MESA_VERBOSE & VERBOSE_API) {
      _mesa_debug(ctx, "glBindBuffer(%s, %u)\n",
                  _mesa_enum_to_string(target), buffer);
   }

   struct gl_buffer_object **bindTarget = get_buffer_target(ctx, target);
   if (!bindTarget) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glBindBufferARB(target %s)",
                  _mesa_enum_to_string(target));
      return;
   }

   bind_buffer_object(ctx, bindTarget, buffer);
}

/**
 * Binds a buffer object to a binding point.
 *
 * The caller is responsible for validating the offset,
 * flushing the vertices and updating NewDriverState.
 */
static void
set_buffer_binding(struct gl_context *ctx,
                   struct gl_buffer_binding *binding,
                   struct gl_buffer_object *bufObj,
                   GLintptr offset,
                   GLsizeiptr size,
                   bool autoSize, gl_buffer_usage usage)
{
   _mesa_reference_buffer_object(ctx, &binding->BufferObject, bufObj);

   binding->Offset = offset;
   binding->Size = size;
   binding->AutomaticSize = autoSize;

   /* If this is a real buffer object, mark it has having been used
    * at some point as an atomic counter buffer.
    */
   if (size >= 0)
      bufObj->UsageHistory |= usage;
}

static void
set_buffer_multi_binding(struct gl_context *ctx,
                         const GLuint *buffers,
                         int idx,
                         const char *caller,
                         struct gl_buffer_binding *binding,
                         GLintptr offset,
                         GLsizeiptr size,
                         bool range,
                         gl_buffer_usage usage)
{
   struct gl_buffer_object *bufObj;
   if (binding->BufferObject && binding->BufferObject->Name == buffers[idx])
      bufObj = binding->BufferObject;
   else
      bufObj = _mesa_multi_bind_lookup_bufferobj(ctx, buffers, idx, caller);

   if (bufObj) {
      if (bufObj == ctx->Shared->NullBufferObj)
         set_buffer_binding(ctx, binding, bufObj, -1, -1, !range, usage);
      else
         set_buffer_binding(ctx, binding, bufObj, offset, size, !range, usage);
   }
}

static void
bind_buffer(struct gl_context *ctx,
            struct gl_buffer_binding *binding,
            struct gl_buffer_object *bufObj,
            GLintptr offset,
            GLsizeiptr size,
            GLboolean autoSize,
            uint64_t driver_state,
            gl_buffer_usage usage)
{
   if (binding->BufferObject == bufObj &&
       binding->Offset == offset &&
       binding->Size == size &&
       binding->AutomaticSize == autoSize) {
      return;
   }

   FLUSH_VERTICES(ctx, 0);
   ctx->NewDriverState |= driver_state;

   set_buffer_binding(ctx, binding, bufObj, offset, size, autoSize, usage);
}

/**
 * Binds a buffer object to a uniform buffer binding point.
 *
 * Unlike set_buffer_binding(), this function also flushes vertices
 * and updates NewDriverState.  It also checks if the binding
 * has actually changed before updating it.
 */
static void
bind_uniform_buffer(struct gl_context *ctx,
                    GLuint index,
                    struct gl_buffer_object *bufObj,
                    GLintptr offset,
                    GLsizeiptr size,
                    GLboolean autoSize)
{
   bind_buffer(ctx, &ctx->UniformBufferBindings[index],
               bufObj, offset, size, autoSize,
               ctx->DriverFlags.NewUniformBuffer,
               USAGE_UNIFORM_BUFFER);
}

/**
 * Binds a buffer object to a shader storage buffer binding point.
 *
 * Unlike set_ssbo_binding(), this function also flushes vertices
 * and updates NewDriverState.  It also checks if the binding
 * has actually changed before updating it.
 */
static void
bind_shader_storage_buffer(struct gl_context *ctx,
                           GLuint index,
                           struct gl_buffer_object *bufObj,
                           GLintptr offset,
                           GLsizeiptr size,
                           GLboolean autoSize)
{
   bind_buffer(ctx, &ctx->ShaderStorageBufferBindings[index],
               bufObj, offset, size, autoSize,
               ctx->DriverFlags.NewShaderStorageBuffer,
               USAGE_SHADER_STORAGE_BUFFER);
}

/**
 * Binds a buffer object to an atomic buffer binding point.
 *
 * Unlike set_atomic_binding(), this function also flushes vertices
 * and updates NewDriverState.  It also checks if the binding
 * has actually changed before updating it.
 */
static void
bind_atomic_buffer(struct gl_context *ctx, unsigned index,
                   struct gl_buffer_object *bufObj, GLintptr offset,
                   GLsizeiptr size, GLboolean autoSize)
{
   bind_buffer(ctx, &ctx->AtomicBufferBindings[index],
               bufObj, offset, size, autoSize,
               ctx->DriverFlags.NewAtomicBuffer,
               USAGE_ATOMIC_COUNTER_BUFFER);
}

/**
 * Bind a buffer object to a uniform block binding point.
 * As above, but offset = 0.
 */
static void
bind_buffer_base_uniform_buffer(struct gl_context *ctx,
				GLuint index,
				struct gl_buffer_object *bufObj)
{
   if (index >= ctx->Const.MaxUniformBufferBindings) {
      _mesa_error(ctx, GL_INVALID_VALUE, "glBindBufferBase(index=%d)", index);
      return;
   }

   _mesa_reference_buffer_object(ctx, &ctx->UniformBuffer, bufObj);

   if (bufObj == ctx->Shared->NullBufferObj)
      bind_uniform_buffer(ctx, index, bufObj, -1, -1, GL_TRUE);
   else
      bind_uniform_buffer(ctx, index, bufObj, 0, 0, GL_TRUE);
}

/**
 * Bind a buffer object to a shader storage block binding point.
 * As above, but offset = 0.
 */
static void
bind_buffer_base_shader_storage_buffer(struct gl_context *ctx,
                                       GLuint index,
                                       struct gl_buffer_object *bufObj)
{
   if (index >= ctx->Const.MaxShaderStorageBufferBindings) {
      _mesa_error(ctx, GL_INVALID_VALUE, "glBindBufferBase(index=%d)", index);
      return;
   }

   _mesa_reference_buffer_object(ctx, &ctx->ShaderStorageBuffer, bufObj);

   if (bufObj == ctx->Shared->NullBufferObj)
      bind_shader_storage_buffer(ctx, index, bufObj, -1, -1, GL_TRUE);
   else
      bind_shader_storage_buffer(ctx, index, bufObj, 0, 0, GL_TRUE);
}

/**
 * Bind a buffer object to a shader storage block binding point.
 * As above, but offset = 0.
 */
static void
bind_buffer_base_atomic_buffer(struct gl_context *ctx,
                               GLuint index,
                               struct gl_buffer_object *bufObj)
{
   if (index >= ctx->Const.MaxAtomicBufferBindings) {
      _mesa_error(ctx, GL_INVALID_VALUE, "glBindBufferBase(index=%d)", index);
      return;
   }

   _mesa_reference_buffer_object(ctx, &ctx->AtomicBuffer, bufObj);

   if (bufObj == ctx->Shared->NullBufferObj)
      bind_atomic_buffer(ctx, index, bufObj, -1, -1, GL_TRUE);
   else
      bind_atomic_buffer(ctx, index, bufObj, 0, 0, GL_TRUE);
}

/**
 * Delete a set of buffer objects.
 *
 * \param n      Number of buffer objects to delete.
 * \param ids    Array of \c n buffer object IDs.
 */
static void
delete_buffers(struct gl_context *ctx, GLsizei n, const GLuint *ids)
{
   FLUSH_VERTICES(ctx, 0);

   _mesa_HashLockMutex(ctx->Shared->BufferObjects);

   for (GLsizei i = 0; i < n; i++) {
      struct gl_buffer_object *bufObj =
         _mesa_lookup_bufferobj_locked(ctx, ids[i]);
      if (bufObj) {
         struct gl_vertex_array_object *vao = ctx->Array.VAO;
         GLuint j;

         assert(bufObj->Name == ids[i] || bufObj == &DummyBufferObject);

         _mesa_buffer_unmap_all_mappings(ctx, bufObj);

         /* unbind any vertex pointers bound to this buffer */
         for (j = 0; j < ARRAY_SIZE(vao->BufferBinding); j++) {
            unbind(ctx, vao, j, bufObj);
         }

         if (ctx->Array.ArrayBufferObj == bufObj) {
            bind_buffer_object(ctx, &ctx->Array.ArrayBufferObj, 0);
         }
         if (vao->IndexBufferObj == bufObj) {
            bind_buffer_object(ctx, &vao->IndexBufferObj, 0);
         }

         /* unbind ARB_draw_indirect binding point */
         if (ctx->DrawIndirectBuffer == bufObj) {
            bind_buffer_object(ctx, &ctx->DrawIndirectBuffer, 0);
         }

         /* unbind ARB_indirect_parameters binding point */
         if (ctx->ParameterBuffer == bufObj) {
            bind_buffer_object(ctx, &ctx->ParameterBuffer, 0);
         }

         /* unbind ARB_compute_shader binding point */
         if (ctx->DispatchIndirectBuffer == bufObj) {
            bind_buffer_object(ctx, &ctx->DispatchIndirectBuffer, 0);
         }

         /* unbind ARB_copy_buffer binding points */
         if (ctx->CopyReadBuffer == bufObj) {
            bind_buffer_object(ctx, &ctx->CopyReadBuffer, 0);
         }
         if (ctx->CopyWriteBuffer == bufObj) {
            bind_buffer_object(ctx, &ctx->CopyWriteBuffer, 0);
         }

         /* unbind transform feedback binding points */
         if (ctx->TransformFeedback.CurrentBuffer == bufObj) {
            bind_buffer_object(ctx, &ctx->TransformFeedback.CurrentBuffer, 0);
         }
         for (j = 0; j < MAX_FEEDBACK_BUFFERS; j++) {
            if (ctx->TransformFeedback.CurrentObject->Buffers[j] == bufObj) {
               _mesa_bind_buffer_base_transform_feedback(ctx,
                                           ctx->TransformFeedback.CurrentObject,
                                           j, ctx->Shared->NullBufferObj,
                                           false);
            }
         }

         /* unbind UBO binding points */
         for (j = 0; j < ctx->Const.MaxUniformBufferBindings; j++) {
            if (ctx->UniformBufferBindings[j].BufferObject == bufObj) {
               bind_buffer_base_uniform_buffer(ctx, j,
                                               ctx->Shared->NullBufferObj);
            }
         }

         if (ctx->UniformBuffer == bufObj) {
            bind_buffer_object(ctx, &ctx->UniformBuffer, 0);
         }

         /* unbind SSBO binding points */
         for (j = 0; j < ctx->Const.MaxShaderStorageBufferBindings; j++) {
            if (ctx->ShaderStorageBufferBindings[j].BufferObject == bufObj) {
               bind_buffer_base_shader_storage_buffer(ctx, j,
                                                    ctx->Shared->NullBufferObj);
            }
         }

         if (ctx->ShaderStorageBuffer == bufObj) {
            bind_buffer_object(ctx, &ctx->ShaderStorageBuffer, 0);
         }

         /* unbind Atomci Buffer binding points */
         for (j = 0; j < ctx->Const.MaxAtomicBufferBindings; j++) {
            if (ctx->AtomicBufferBindings[j].BufferObject == bufObj) {
               bind_buffer_base_atomic_buffer(ctx, j,
                                              ctx->Shared->NullBufferObj);
            }
         }

         if (ctx->AtomicBuffer == bufObj) {
            bind_buffer_object(ctx, &ctx->AtomicBuffer, 0);
         }

         /* unbind any pixel pack/unpack pointers bound to this buffer */
         if (ctx->Pack.BufferObj == bufObj) {
            bind_buffer_object(ctx, &ctx->Pack.BufferObj, 0);
         }
         if (ctx->Unpack.BufferObj == bufObj) {
            bind_buffer_object(ctx, &ctx->Unpack.BufferObj, 0);
         }

         if (ctx->Texture.BufferObject == bufObj) {
            bind_buffer_object(ctx, &ctx->Texture.BufferObject, 0);
         }

         if (ctx->ExternalVirtualMemoryBuffer == bufObj) {
            bind_buffer_object(ctx, &ctx->ExternalVirtualMemoryBuffer, 0);
         }

         /* unbind query buffer binding point */
         if (ctx->QueryBuffer == bufObj) {
            bind_buffer_object(ctx, &ctx->QueryBuffer, 0);
         }

         /* The ID is immediately freed for re-use */
         _mesa_HashRemoveLocked(ctx->Shared->BufferObjects, ids[i]);
         /* Make sure we do not run into the classic ABA problem on bind.
          * We don't want to allow re-binding a buffer object that's been
          * "deleted" by glDeleteBuffers().
          *
          * The explicit rebinding to the default object in the current context
          * prevents the above in the current context, but another context
          * sharing the same objects might suffer from this problem.
          * The alternative would be to do the hash lookup in any case on bind
          * which would introduce more runtime overhead than this.
          */
         bufObj->DeletePending = GL_TRUE;
         _mesa_reference_buffer_object(ctx, &bufObj, NULL);
      }
   }

   _mesa_HashUnlockMutex(ctx->Shared->BufferObjects);
}


void GLAPIENTRY
_mesa_DeleteBuffers_no_error(GLsizei n, const GLuint *ids)
{
   GET_CURRENT_CONTEXT(ctx);
   delete_buffers(ctx, n, ids);
}


void GLAPIENTRY
_mesa_DeleteBuffers(GLsizei n, const GLuint *ids)
{
   GET_CURRENT_CONTEXT(ctx);

   if (n < 0) {
      _mesa_error(ctx, GL_INVALID_VALUE, "glDeleteBuffersARB(n)");
      return;
   }

   delete_buffers(ctx, n, ids);
}


/**
 * This is the implementation for glGenBuffers and glCreateBuffers. It is not
 * exposed to the rest of Mesa to encourage the use of nameless buffers in
 * driver internals.
 */
static void
create_buffers(struct gl_context *ctx, GLsizei n, GLuint *buffers, bool dsa)
{
   GLuint first;
   struct gl_buffer_object *buf;

   if (!buffers)
      return;

   /*
    * This must be atomic (generation and allocation of buffer object IDs)
    */
   _mesa_HashLockMutex(ctx->Shared->BufferObjects);

   first = _mesa_HashFindFreeKeyBlock(ctx->Shared->BufferObjects, n);

   /* Insert the ID and pointer into the hash table. If non-DSA, insert a
    * DummyBufferObject.  Otherwise, create a new buffer object and insert
    * it.
    */
   for (int i = 0; i < n; i++) {
      buffers[i] = first + i;
      if (dsa) {
         assert(ctx->Driver.NewBufferObject);
         buf = ctx->Driver.NewBufferObject(ctx, buffers[i]);
         if (!buf) {
            _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCreateBuffers");
            _mesa_HashUnlockMutex(ctx->Shared->BufferObjects);
            return;
         }
      }
      else
         buf = &DummyBufferObject;

      _mesa_HashInsertLocked(ctx->Shared->BufferObjects, buffers[i], buf);
   }

   _mesa_HashUnlockMutex(ctx->Shared->BufferObjects);
}


static void
create_buffers_err(struct gl_context *ctx, GLsizei n, GLuint *buffers, bool dsa)
{
   const char *func = dsa ? "glCreateBuffers" : "glGenBuffers";

   if (MESA_VERBOSE & VERBOSE_API)
      _mesa_debug(ctx, "%s(%d)\n", func, n);

   if (n < 0) {
      _mesa_error(ctx, GL_INVALID_VALUE, "%s(n %d < 0)", func, n);
      return;
   }

   create_buffers(ctx, n, buffers, dsa);
}

/**
 * Generate a set of unique buffer object IDs and store them in \c buffers.
 *
 * \param n        Number of IDs to generate.
 * \param buffers  Array of \c n locations to store the IDs.
 */
void GLAPIENTRY
_mesa_GenBuffers_no_error(GLsizei n, GLuint *buffers)
{
   GET_CURRENT_CONTEXT(ctx);
   create_buffers(ctx, n, buffers, false);
}


void GLAPIENTRY
_mesa_GenBuffers(GLsizei n, GLuint *buffers)
{
   GET_CURRENT_CONTEXT(ctx);
   create_buffers_err(ctx, n, buffers, false);
}

/**
 * Create a set of buffer objects and store their unique IDs in \c buffers.
 *
 * \param n        Number of IDs to generate.
 * \param buffers  Array of \c n locations to store the IDs.
 */
void GLAPIENTRY
_mesa_CreateBuffers_no_error(GLsizei n, GLuint *buffers)
{
   GET_CURRENT_CONTEXT(ctx);
   create_buffers(ctx, n, buffers, true);
}


void GLAPIENTRY
_mesa_CreateBuffers(GLsizei n, GLuint *buffers)
{
   GET_CURRENT_CONTEXT(ctx);
   create_buffers_err(ctx, n, buffers, true);
}


/**
 * Determine if ID is the name of a buffer object.
 *
 * \param id  ID of the potential buffer object.
 * \return  \c GL_TRUE if \c id is the name of a buffer object,
 *          \c GL_FALSE otherwise.
 */
GLboolean GLAPIENTRY
_mesa_IsBuffer(GLuint id)
{
   struct gl_buffer_object *bufObj;
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, GL_FALSE);

   bufObj = _mesa_lookup_bufferobj(ctx, id);

   return bufObj && bufObj != &DummyBufferObject;
}


static bool
validate_buffer_storage(struct gl_context *ctx,
                        struct gl_buffer_object *bufObj, GLsizeiptr size,
                        GLbitfield flags, const char *func)
{
   if (size <= 0) {
      _mesa_error(ctx, GL_INVALID_VALUE, "%s(size <= 0)", func);
      return false;
   }

   GLbitfield valid_flags = GL_MAP_READ_BIT |
                            GL_MAP_WRITE_BIT |
                            GL_MAP_PERSISTENT_BIT |
                            GL_MAP_COHERENT_BIT |
                            GL_DYNAMIC_STORAGE_BIT |
                            GL_CLIENT_STORAGE_BIT;

   if (ctx->Extensions.ARB_sparse_buffer)
      valid_flags |= GL_SPARSE_STORAGE_BIT_ARB;

   if (flags & ~valid_flags) {
      _mesa_error(ctx, GL_INVALID_VALUE, "%s(invalid flag bits set)", func);
      return false;
   }

   /* The Errors section of the GL_ARB_sparse_buffer spec says:
    *
    *    "INVALID_VALUE is generated by BufferStorage if <flags> contains
    *     SPARSE_STORAGE_BIT_ARB and <flags> also contains any combination of
    *     MAP_READ_BIT or MAP_WRITE_BIT."
    */
   if (flags & GL_SPARSE_STORAGE_BIT_ARB &&
       flags & (GL_MAP_READ_BIT | GL_MAP_WRITE_BIT)) {
      _mesa_error(ctx, GL_INVALID_VALUE, "%s(SPARSE_STORAGE and READ/WRITE)", func);
      return false;
   }

   if (flags & GL_MAP_PERSISTENT_BIT &&
       !(flags & (GL_MAP_READ_BIT | GL_MAP_WRITE_BIT))) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(PERSISTENT and flags!=READ/WRITE)", func);
      return false;
   }

   if (flags & GL_MAP_COHERENT_BIT && !(flags & GL_MAP_PERSISTENT_BIT)) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(COHERENT and flags!=PERSISTENT)", func);
      return false;
   }

   if (bufObj->Immutable || bufObj->HandleAllocated) {
      _mesa_error(ctx, GL_INVALID_OPERATION, "%s(immutable)", func);
      return false;
   }

   return true;
}


static void
buffer_storage(struct gl_context *ctx, struct gl_buffer_object *bufObj,
               struct gl_memory_object *memObj, GLenum target,
               GLsizeiptr size, const GLvoid *data, GLbitfield flags,
               GLuint64 offset, const char *func)
{
   GLboolean res;

   /* Unmap the existing buffer.  We'll replace it now.  Not an error. */
   _mesa_buffer_unmap_all_mappings(ctx, bufObj);

   FLUSH_VERTICES(ctx, 0);

   bufObj->Written = GL_TRUE;
   bufObj->Immutable = GL_TRUE;
   bufObj->MinMaxCacheDirty = true;

   if (memObj) {
      assert(ctx->Driver.BufferDataMem);
      res = ctx->Driver.BufferDataMem(ctx, target, size, memObj, offset,
                                      GL_DYNAMIC_DRAW, bufObj);
   }
   else {
      assert(ctx->Driver.BufferData);
      res = ctx->Driver.BufferData(ctx, target, size, data, GL_DYNAMIC_DRAW,
                                   flags, bufObj);
   }

   if (!res) {
      if (target == GL_EXTERNAL_VIRTUAL_MEMORY_BUFFER_AMD) {
         /* Even though the interaction between AMD_pinned_memory and
          * glBufferStorage is not described in the spec, Graham Sellers
          * said that it should behave the same as glBufferData.
          */
         _mesa_error(ctx, GL_INVALID_OPERATION, "%s", func);
      }
      else {
         _mesa_error(ctx, GL_OUT_OF_MEMORY, "%s", func);
      }
   }
}


static ALWAYS_INLINE void
inlined_buffer_storage(GLenum target, GLuint buffer, GLsizeiptr size,
                       const GLvoid *data, GLbitfield flags,
                       GLuint memory, GLuint64 offset,
                       bool dsa, bool mem, bool no_error, const char *func)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;
   struct gl_memory_object *memObj = NULL;

   if (mem) {
      if (!no_error) {
         if (!ctx->Extensions.EXT_memory_object) {
            _mesa_error(ctx, GL_INVALID_OPERATION, "%s(unsupported)", func);
            return;
         }

         /* From the EXT_external_objects spec:
          *
          *   "An INVALID_VALUE error is generated by BufferStorageMemEXT and
          *   NamedBufferStorageMemEXT if <memory> is 0, or ..."
          */
         if (memory == 0) {
            _mesa_error(ctx, GL_INVALID_VALUE, "%s(memory == 0)", func);
         }
      }

      memObj = _mesa_lookup_memory_object(ctx, memory);
      if (!memObj)
         return;

      /* From the EXT_external_objects spec:
       *
       *   "An INVALID_OPERATION error is generated if <memory> names a
       *   valid memory object which has no associated memory."
       */
      if (!no_error && !memObj->Immutable) {
         _mesa_error(ctx, GL_INVALID_OPERATION, "%s(no associated memory)",
                     func);
         return;
      }
   }

   if (dsa) {
      if (no_error) {
         bufObj = _mesa_lookup_bufferobj(ctx, buffer);
      } else {
         bufObj = _mesa_lookup_bufferobj_err(ctx, buffer, func);
         if (!bufObj)
            return;
      }
   } else {
      if (no_error) {
         struct gl_buffer_object **bufObjPtr = get_buffer_target(ctx, target);
         bufObj = *bufObjPtr;
      } else {
         bufObj = get_buffer(ctx, func, target, GL_INVALID_OPERATION);
         if (!bufObj)
            return;
      }
   }

   if (no_error || validate_buffer_storage(ctx, bufObj, size, flags, func))
      buffer_storage(ctx, bufObj, memObj, target, size, data, flags, offset, func);
}


void GLAPIENTRY
_mesa_BufferStorage_no_error(GLenum target, GLsizeiptr size,
                             const GLvoid *data, GLbitfield flags)
{
   inlined_buffer_storage(target, 0, size, data, flags, GL_NONE, 0,
                          false, false, true, "glBufferStorage");
}


void GLAPIENTRY
_mesa_BufferStorage(GLenum target, GLsizeiptr size, const GLvoid *data,
                    GLbitfield flags)
{
   inlined_buffer_storage(target, 0, size, data, flags, GL_NONE, 0,
                          false, false, false, "glBufferStorage");
}


void GLAPIENTRY
_mesa_BufferStorageMemEXT(GLenum target, GLsizeiptr size,
                          GLuint memory, GLuint64 offset)
{
   inlined_buffer_storage(target, 0, size, NULL, 0, memory, offset,
                          false, true, false, "glBufferStorageMemEXT");
}


void GLAPIENTRY
_mesa_BufferStorageMemEXT_no_error(GLenum target, GLsizeiptr size,
                                   GLuint memory, GLuint64 offset)
{
   inlined_buffer_storage(target, 0, size, NULL, 0, memory, offset,
                          false, true, true, "glBufferStorageMemEXT");
}


void GLAPIENTRY
_mesa_NamedBufferStorage_no_error(GLuint buffer, GLsizeiptr size,
                                  const GLvoid *data, GLbitfield flags)
{
   /* In direct state access, buffer objects have an unspecified target
    * since they are not required to be bound.
    */
   inlined_buffer_storage(GL_NONE, buffer, size, data, flags, GL_NONE, 0,
                          true, false, true, "glNamedBufferStorage");
}


void GLAPIENTRY
_mesa_NamedBufferStorage(GLuint buffer, GLsizeiptr size, const GLvoid *data,
                         GLbitfield flags)
{
   /* In direct state access, buffer objects have an unspecified target
    * since they are not required to be bound.
    */
   inlined_buffer_storage(GL_NONE, buffer, size, data, flags, GL_NONE, 0,
                          true, false, false, "glNamedBufferStorage");
}

void GLAPIENTRY
_mesa_NamedBufferStorageMemEXT(GLuint buffer, GLsizeiptr size,
                               GLuint memory, GLuint64 offset)
{
   inlined_buffer_storage(GL_NONE, buffer, size, GL_NONE, 0, memory, offset,
                          true, true, false, "glNamedBufferStorageMemEXT");
}


void GLAPIENTRY
_mesa_NamedBufferStorageMemEXT_no_error(GLuint buffer, GLsizeiptr size,
                                        GLuint memory, GLuint64 offset)
{
   inlined_buffer_storage(GL_NONE, buffer, size, GL_NONE, 0, memory, offset,
                          true, true, true, "glNamedBufferStorageMemEXT");
}


static ALWAYS_INLINE void
buffer_data(struct gl_context *ctx, struct gl_buffer_object *bufObj,
            GLenum target, GLsizeiptr size, const GLvoid *data, GLenum usage,
            const char *func, bool no_error)
{
   bool valid_usage;

   if (MESA_VERBOSE & VERBOSE_API) {
      _mesa_debug(ctx, "%s(%s, %ld, %p, %s)\n",
                  func,
                  _mesa_enum_to_string(target),
                  (long int) size, data,
                  _mesa_enum_to_string(usage));
   }

   if (!no_error) {
      if (size < 0) {
         _mesa_error(ctx, GL_INVALID_VALUE, "%s(size < 0)", func);
         return;
      }

      switch (usage) {
      case GL_STREAM_DRAW_ARB:
         valid_usage = (ctx->API != API_OPENGLES);
         break;
      case GL_STATIC_DRAW_ARB:
      case GL_DYNAMIC_DRAW_ARB:
         valid_usage = true;
         break;
      case GL_STREAM_READ_ARB:
      case GL_STREAM_COPY_ARB:
      case GL_STATIC_READ_ARB:
      case GL_STATIC_COPY_ARB:
      case GL_DYNAMIC_READ_ARB:
      case GL_DYNAMIC_COPY_ARB:
         valid_usage = _mesa_is_desktop_gl(ctx) || _mesa_is_gles3(ctx);
         break;
      default:
         valid_usage = false;
         break;
      }

      if (!valid_usage) {
         _mesa_error(ctx, GL_INVALID_ENUM, "%s(invalid usage: %s)", func,
                     _mesa_enum_to_string(usage));
         return;
      }

      if (bufObj->Immutable || bufObj->HandleAllocated) {
         _mesa_error(ctx, GL_INVALID_OPERATION, "%s(immutable)", func);
         return;
      }
   }

   /* Unmap the existing buffer.  We'll replace it now.  Not an error. */
   _mesa_buffer_unmap_all_mappings(ctx, bufObj);

   FLUSH_VERTICES(ctx, 0);

   bufObj->Written = GL_TRUE;
   bufObj->MinMaxCacheDirty = true;

#ifdef VBO_DEBUG
   printf("glBufferDataARB(%u, sz %ld, from %p, usage 0x%x)\n",
                bufObj->Name, size, data, usage);
#endif

#ifdef BOUNDS_CHECK
   size += 100;
#endif

   assert(ctx->Driver.BufferData);
   if (!ctx->Driver.BufferData(ctx, target, size, data, usage,
                               GL_MAP_READ_BIT |
                               GL_MAP_WRITE_BIT |
                               GL_DYNAMIC_STORAGE_BIT,
                               bufObj)) {
      if (target == GL_EXTERNAL_VIRTUAL_MEMORY_BUFFER_AMD) {
         if (!no_error) {
            /* From GL_AMD_pinned_memory:
             *
             *   INVALID_OPERATION is generated by BufferData if <target> is
             *   EXTERNAL_VIRTUAL_MEMORY_BUFFER_AMD, and the store cannot be
             *   mapped to the GPU address space.
             */
            _mesa_error(ctx, GL_INVALID_OPERATION, "%s", func);
         }
      } else {
         _mesa_error(ctx, GL_OUT_OF_MEMORY, "%s", func);
      }
   }
}

static void
buffer_data_error(struct gl_context *ctx, struct gl_buffer_object *bufObj,
                  GLenum target, GLsizeiptr size, const GLvoid *data,
                  GLenum usage, const char *func)
{
   buffer_data(ctx, bufObj, target, size, data, usage, func, false);
}

static void
buffer_data_no_error(struct gl_context *ctx, struct gl_buffer_object *bufObj,
                     GLenum target, GLsizeiptr size, const GLvoid *data,
                     GLenum usage, const char *func)
{
   buffer_data(ctx, bufObj, target, size, data, usage, func, true);
}

void
_mesa_buffer_data(struct gl_context *ctx, struct gl_buffer_object *bufObj,
                  GLenum target, GLsizeiptr size, const GLvoid *data,
                  GLenum usage, const char *func)
{
   buffer_data_error(ctx, bufObj, target, size, data, usage, func);
}

void GLAPIENTRY
_mesa_BufferData_no_error(GLenum target, GLsizeiptr size, const GLvoid *data,
                          GLenum usage)
{
   GET_CURRENT_CONTEXT(ctx);

   struct gl_buffer_object **bufObj = get_buffer_target(ctx, target);
   buffer_data_no_error(ctx, *bufObj, target, size, data, usage,
                        "glBufferData");
}

void GLAPIENTRY
_mesa_BufferData(GLenum target, GLsizeiptr size,
                 const GLvoid *data, GLenum usage)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   bufObj = get_buffer(ctx, "glBufferData", target, GL_INVALID_OPERATION);
   if (!bufObj)
      return;

   _mesa_buffer_data(ctx, bufObj, target, size, data, usage,
                     "glBufferData");
}

void GLAPIENTRY
_mesa_NamedBufferData_no_error(GLuint buffer, GLsizeiptr size,
                               const GLvoid *data, GLenum usage)
{
   GET_CURRENT_CONTEXT(ctx);

   struct gl_buffer_object *bufObj = _mesa_lookup_bufferobj(ctx, buffer);
   buffer_data_no_error(ctx, bufObj, GL_NONE, size, data, usage,
                        "glNamedBufferData");
}

void GLAPIENTRY
_mesa_NamedBufferData(GLuint buffer, GLsizeiptr size, const GLvoid *data,
                      GLenum usage)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   bufObj = _mesa_lookup_bufferobj_err(ctx, buffer, "glNamedBufferData");
   if (!bufObj)
      return;

   /* In direct state access, buffer objects have an unspecified target since
    * they are not required to be bound.
    */
   _mesa_buffer_data(ctx, bufObj, GL_NONE, size, data, usage,
                     "glNamedBufferData");
}


static bool
validate_buffer_sub_data(struct gl_context *ctx,
                         struct gl_buffer_object *bufObj,
                         GLintptr offset, GLsizeiptr size,
                         const char *func)
{
   if (!buffer_object_subdata_range_good(ctx, bufObj, offset, size,
                                         true, func)) {
      /* error already recorded */
      return false;
   }

   if (bufObj->Immutable &&
       !(bufObj->StorageFlags & GL_DYNAMIC_STORAGE_BIT)) {
      _mesa_error(ctx, GL_INVALID_OPERATION, "%s", func);
      return false;
   }

   if ((bufObj->Usage == GL_STATIC_DRAW ||
        bufObj->Usage == GL_STATIC_COPY) &&
       bufObj->NumSubDataCalls >= BUFFER_WARNING_CALL_COUNT - 1) {
      /* If the application declared the buffer as static draw/copy or stream
       * draw, it should not be frequently modified with glBufferSubData.
       */
      BUFFER_USAGE_WARNING(ctx,
                           "using %s(buffer %u, offset %u, size %u) to "
                           "update a %s buffer",
                           func, bufObj->Name, offset, size,
                           _mesa_enum_to_string(bufObj->Usage));
   }

   return true;
}


/**
 * Implementation for glBufferSubData and glNamedBufferSubData.
 *
 * \param ctx     GL context.
 * \param bufObj  The buffer object.
 * \param offset  Offset of the first byte of the subdata range.
 * \param size    Size, in bytes, of the subdata range.
 * \param data    The data store.
 * \param func  Name of calling function for recording errors.
 *
 */
void
_mesa_buffer_sub_data(struct gl_context *ctx, struct gl_buffer_object *bufObj,
                      GLintptr offset, GLsizeiptr size, const GLvoid *data)
{
   if (size == 0)
      return;

   bufObj->NumSubDataCalls++;
   bufObj->Written = GL_TRUE;
   bufObj->MinMaxCacheDirty = true;

   assert(ctx->Driver.BufferSubData);
   ctx->Driver.BufferSubData(ctx, offset, size, data, bufObj);
}


static ALWAYS_INLINE void
buffer_sub_data(GLenum target, GLuint buffer, GLintptr offset,
                GLsizeiptr size, const GLvoid *data,
                bool dsa, bool no_error, const char *func)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   if (dsa) {
      if (no_error) {
         bufObj = _mesa_lookup_bufferobj(ctx, buffer);
      } else {
         bufObj = _mesa_lookup_bufferobj_err(ctx, buffer, func);
         if (!bufObj)
            return;
      }
   } else {
      if (no_error) {
         struct gl_buffer_object **bufObjPtr = get_buffer_target(ctx, target);
         bufObj = *bufObjPtr;
      } else {
         bufObj = get_buffer(ctx, func, target, GL_INVALID_OPERATION);
         if (!bufObj)
            return;
      }
   }

   if (no_error || validate_buffer_sub_data(ctx, bufObj, offset, size, func))
      _mesa_buffer_sub_data(ctx, bufObj, offset, size, data);
}


void GLAPIENTRY
_mesa_BufferSubData_no_error(GLenum target, GLintptr offset,
                             GLsizeiptr size, const GLvoid *data)
{
   buffer_sub_data(target, 0, offset, size, data, false, true,
                   "glBufferSubData");
}


void GLAPIENTRY
_mesa_BufferSubData(GLenum target, GLintptr offset,
                    GLsizeiptr size, const GLvoid *data)
{
   buffer_sub_data(target, 0, offset, size, data, false, false,
                   "glBufferSubData");
}

void GLAPIENTRY
_mesa_NamedBufferSubData_no_error(GLuint buffer, GLintptr offset,
                                  GLsizeiptr size, const GLvoid *data)
{
   buffer_sub_data(0, buffer, offset, size, data, true, true,
                   "glNamedBufferSubData");
}

void GLAPIENTRY
_mesa_NamedBufferSubData(GLuint buffer, GLintptr offset,
                         GLsizeiptr size, const GLvoid *data)
{
   buffer_sub_data(0, buffer, offset, size, data, true, false,
                   "glNamedBufferSubData");
}


void GLAPIENTRY
_mesa_GetBufferSubData(GLenum target, GLintptr offset,
                       GLsizeiptr size, GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   bufObj = get_buffer(ctx, "glGetBufferSubData", target,
                       GL_INVALID_OPERATION);
   if (!bufObj)
      return;

   if (!buffer_object_subdata_range_good(ctx, bufObj, offset, size, false,
                                         "glGetBufferSubData")) {
      return;
   }

   assert(ctx->Driver.GetBufferSubData);
   ctx->Driver.GetBufferSubData(ctx, offset, size, data, bufObj);
}

void GLAPIENTRY
_mesa_GetNamedBufferSubData(GLuint buffer, GLintptr offset,
                            GLsizeiptr size, GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   bufObj = _mesa_lookup_bufferobj_err(ctx, buffer,
                                       "glGetNamedBufferSubData");
   if (!bufObj)
      return;

   if (!buffer_object_subdata_range_good(ctx, bufObj, offset, size, false,
                                         "glGetNamedBufferSubData")) {
      return;
   }

   assert(ctx->Driver.GetBufferSubData);
   ctx->Driver.GetBufferSubData(ctx, offset, size, data, bufObj);
}


/**
 * \param subdata   true if caller is *SubData, false if *Data
 */
static ALWAYS_INLINE void
clear_buffer_sub_data(struct gl_context *ctx, struct gl_buffer_object *bufObj,
                      GLenum internalformat, GLintptr offset, GLsizeiptr size,
                      GLenum format, GLenum type, const GLvoid *data,
                      const char *func, bool subdata, bool no_error)
{
   mesa_format mesaFormat;
   GLubyte clearValue[MAX_PIXEL_BYTES];
   GLsizeiptr clearValueSize;

   /* This checks for disallowed mappings. */
   if (!no_error && !buffer_object_subdata_range_good(ctx, bufObj, offset, size,
                                                      subdata, func)) {
      return;
   }

   if (no_error) {
      mesaFormat = _mesa_get_texbuffer_format(ctx, internalformat);
   } else {
      mesaFormat = validate_clear_buffer_format(ctx, internalformat,
                                                format, type, func);
   }

   if (mesaFormat == MESA_FORMAT_NONE)
      return;

   clearValueSize = _mesa_get_format_bytes(mesaFormat);
   if (!no_error &&
       (offset % clearValueSize != 0 || size % clearValueSize != 0)) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(offset or size is not a multiple of "
                  "internalformat size)", func);
      return;
   }

   /* Bail early. Negative size has already been checked. */
   if (size == 0)
      return;

   bufObj->MinMaxCacheDirty = true;

   if (data == NULL) {
      /* clear to zeros, per the spec */
      ctx->Driver.ClearBufferSubData(ctx, offset, size,
                                     NULL, clearValueSize, bufObj);
      return;
   }

   if (!convert_clear_buffer_data(ctx, mesaFormat, clearValue,
                                  format, type, data, func)) {
      return;
   }

   ctx->Driver.ClearBufferSubData(ctx, offset, size,
                                  clearValue, clearValueSize, bufObj);
}

static void
clear_buffer_sub_data_error(struct gl_context *ctx,
                            struct gl_buffer_object *bufObj,
                            GLenum internalformat, GLintptr offset,
                            GLsizeiptr size, GLenum format, GLenum type,
                            const GLvoid *data, const char *func, bool subdata)
{
   clear_buffer_sub_data(ctx, bufObj, internalformat, offset, size, format,
                         type, data, func, subdata, false);
}


static void
clear_buffer_sub_data_no_error(struct gl_context *ctx,
                               struct gl_buffer_object *bufObj,
                               GLenum internalformat, GLintptr offset,
                               GLsizeiptr size, GLenum format, GLenum type,
                               const GLvoid *data, const char *func,
                               bool subdata)
{
   clear_buffer_sub_data(ctx, bufObj, internalformat, offset, size, format,
                         type, data, func, subdata, true);
}


void GLAPIENTRY
_mesa_ClearBufferData_no_error(GLenum target, GLenum internalformat,
                               GLenum format, GLenum type, const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);

   struct gl_buffer_object **bufObj = get_buffer_target(ctx, target);
   clear_buffer_sub_data_no_error(ctx, *bufObj, internalformat, 0,
                                  (*bufObj)->Size, format, type, data,
                                  "glClearBufferData", false);
}


void GLAPIENTRY
_mesa_ClearBufferData(GLenum target, GLenum internalformat, GLenum format,
                      GLenum type, const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   bufObj = get_buffer(ctx, "glClearBufferData", target, GL_INVALID_VALUE);
   if (!bufObj)
      return;

   clear_buffer_sub_data_error(ctx, bufObj, internalformat, 0, bufObj->Size,
                               format, type, data, "glClearBufferData", false);
}


void GLAPIENTRY
_mesa_ClearNamedBufferData_no_error(GLuint buffer, GLenum internalformat,
                                    GLenum format, GLenum type,
                                    const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);

   struct gl_buffer_object *bufObj = _mesa_lookup_bufferobj(ctx, buffer);
   clear_buffer_sub_data_no_error(ctx, bufObj, internalformat, 0, bufObj->Size,
                                  format, type, data, "glClearNamedBufferData",
                                  false);
}


void GLAPIENTRY
_mesa_ClearNamedBufferData(GLuint buffer, GLenum internalformat,
                           GLenum format, GLenum type, const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   bufObj = _mesa_lookup_bufferobj_err(ctx, buffer, "glClearNamedBufferData");
   if (!bufObj)
      return;

   clear_buffer_sub_data_error(ctx, bufObj, internalformat, 0, bufObj->Size,
                               format, type, data, "glClearNamedBufferData",
                               false);
}


void GLAPIENTRY
_mesa_ClearBufferSubData_no_error(GLenum target, GLenum internalformat,
                                  GLintptr offset, GLsizeiptr size,
                                  GLenum format, GLenum type,
                                  const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);

   struct gl_buffer_object **bufObj = get_buffer_target(ctx, target);
   clear_buffer_sub_data_no_error(ctx, *bufObj, internalformat, offset, size,
                                  format, type, data, "glClearBufferSubData",
                                  true);
}


void GLAPIENTRY
_mesa_ClearBufferSubData(GLenum target, GLenum internalformat,
                         GLintptr offset, GLsizeiptr size,
                         GLenum format, GLenum type,
                         const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   bufObj = get_buffer(ctx, "glClearBufferSubData", target, GL_INVALID_VALUE);
   if (!bufObj)
      return;

   clear_buffer_sub_data_error(ctx, bufObj, internalformat, offset, size,
                               format, type, data, "glClearBufferSubData",
                               true);
}


void GLAPIENTRY
_mesa_ClearNamedBufferSubData_no_error(GLuint buffer, GLenum internalformat,
                                       GLintptr offset, GLsizeiptr size,
                                       GLenum format, GLenum type,
                                       const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);

   struct gl_buffer_object *bufObj = _mesa_lookup_bufferobj(ctx, buffer);
   clear_buffer_sub_data_no_error(ctx, bufObj, internalformat, offset, size,
                                  format, type, data,
                                  "glClearNamedBufferSubData", true);
}


void GLAPIENTRY
_mesa_ClearNamedBufferSubData(GLuint buffer, GLenum internalformat,
                              GLintptr offset, GLsizeiptr size,
                              GLenum format, GLenum type,
                              const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   bufObj = _mesa_lookup_bufferobj_err(ctx, buffer,
                                       "glClearNamedBufferSubData");
   if (!bufObj)
      return;

   clear_buffer_sub_data_error(ctx, bufObj, internalformat, offset, size,
                               format, type, data, "glClearNamedBufferSubData",
                               true);
}

static GLboolean
unmap_buffer(struct gl_context *ctx, struct gl_buffer_object *bufObj)
{
   GLboolean status = ctx->Driver.UnmapBuffer(ctx, bufObj, MAP_USER);
   bufObj->Mappings[MAP_USER].AccessFlags = 0;
   assert(bufObj->Mappings[MAP_USER].Pointer == NULL);
   assert(bufObj->Mappings[MAP_USER].Offset == 0);
   assert(bufObj->Mappings[MAP_USER].Length == 0);

   return status;
}

static GLboolean
validate_and_unmap_buffer(struct gl_context *ctx,
                          struct gl_buffer_object *bufObj,
                          const char *func)
{
   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, GL_FALSE);

   if (!_mesa_bufferobj_mapped(bufObj, MAP_USER)) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(buffer is not mapped)", func);
      return GL_FALSE;
   }

#ifdef BOUNDS_CHECK
   if (bufObj->Access != GL_READ_ONLY_ARB) {
      GLubyte *buf = (GLubyte *) bufObj->Pointer;
      GLuint i;
      /* check that last 100 bytes are still = magic value */
      for (i = 0; i < 100; i++) {
         GLuint pos = bufObj->Size - i - 1;
         if (buf[pos] != 123) {
            _mesa_warning(ctx, "Out of bounds buffer object write detected"
                          " at position %d (value = %u)\n",
                          pos, buf[pos]);
         }
      }
   }
#endif

#ifdef VBO_DEBUG
   if (bufObj->AccessFlags & GL_MAP_WRITE_BIT) {
      GLuint i, unchanged = 0;
      GLubyte *b = (GLubyte *) bufObj->Pointer;
      GLint pos = -1;
      /* check which bytes changed */
      for (i = 0; i < bufObj->Size - 1; i++) {
         if (b[i] == (i & 0xff) && b[i+1] == ((i+1) & 0xff)) {
            unchanged++;
            if (pos == -1)
               pos = i;
         }
      }
      if (unchanged) {
         printf("glUnmapBufferARB(%u): %u of %ld unchanged, starting at %d\n",
                      bufObj->Name, unchanged, bufObj->Size, pos);
      }
   }
#endif

   return unmap_buffer(ctx, bufObj);
}

GLboolean GLAPIENTRY
_mesa_UnmapBuffer_no_error(GLenum target)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object **bufObjPtr = get_buffer_target(ctx, target);
   struct gl_buffer_object *bufObj = *bufObjPtr;

   return unmap_buffer(ctx, bufObj);
}

GLboolean GLAPIENTRY
_mesa_UnmapBuffer(GLenum target)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   bufObj = get_buffer(ctx, "glUnmapBuffer", target, GL_INVALID_OPERATION);
   if (!bufObj)
      return GL_FALSE;

   return validate_and_unmap_buffer(ctx, bufObj, "glUnmapBuffer");
}

GLboolean GLAPIENTRY
_mesa_UnmapNamedBuffer_no_error(GLuint buffer)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj = _mesa_lookup_bufferobj(ctx, buffer);

   return unmap_buffer(ctx, bufObj);
}

GLboolean GLAPIENTRY
_mesa_UnmapNamedBuffer(GLuint buffer)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   bufObj = _mesa_lookup_bufferobj_err(ctx, buffer, "glUnmapNamedBuffer");
   if (!bufObj)
      return GL_FALSE;

   return validate_and_unmap_buffer(ctx, bufObj, "glUnmapNamedBuffer");
}


static bool
get_buffer_parameter(struct gl_context *ctx,
                     struct gl_buffer_object *bufObj, GLenum pname,
                     GLint64 *params, const char *func)
{
   switch (pname) {
   case GL_BUFFER_SIZE_ARB:
      *params = bufObj->Size;
      break;
   case GL_BUFFER_USAGE_ARB:
      *params = bufObj->Usage;
      break;
   case GL_BUFFER_ACCESS_ARB:
      *params = simplified_access_mode(ctx,
                            bufObj->Mappings[MAP_USER].AccessFlags);
      break;
   case GL_BUFFER_MAPPED_ARB:
      *params = _mesa_bufferobj_mapped(bufObj, MAP_USER);
      break;
   case GL_BUFFER_ACCESS_FLAGS:
      if (!ctx->Extensions.ARB_map_buffer_range)
         goto invalid_pname;
      *params = bufObj->Mappings[MAP_USER].AccessFlags;
      break;
   case GL_BUFFER_MAP_OFFSET:
      if (!ctx->Extensions.ARB_map_buffer_range)
         goto invalid_pname;
      *params = bufObj->Mappings[MAP_USER].Offset;
      break;
   case GL_BUFFER_MAP_LENGTH:
      if (!ctx->Extensions.ARB_map_buffer_range)
         goto invalid_pname;
      *params = bufObj->Mappings[MAP_USER].Length;
      break;
   case GL_BUFFER_IMMUTABLE_STORAGE:
      if (!ctx->Extensions.ARB_buffer_storage)
         goto invalid_pname;
      *params = bufObj->Immutable;
      break;
   case GL_BUFFER_STORAGE_FLAGS:
      if (!ctx->Extensions.ARB_buffer_storage)
         goto invalid_pname;
      *params = bufObj->StorageFlags;
      break;
   default:
      goto invalid_pname;
   }

   return true;

invalid_pname:
   _mesa_error(ctx, GL_INVALID_ENUM, "%s(invalid pname: %s)", func,
               _mesa_enum_to_string(pname));
   return false;
}

void GLAPIENTRY
_mesa_GetBufferParameteriv(GLenum target, GLenum pname, GLint *params)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;
   GLint64 parameter;

   bufObj = get_buffer(ctx, "glGetBufferParameteriv", target,
                       GL_INVALID_OPERATION);
   if (!bufObj)
      return;

   if (!get_buffer_parameter(ctx, bufObj, pname, &parameter,
                             "glGetBufferParameteriv"))
      return; /* Error already recorded. */

   *params = (GLint) parameter;
}

void GLAPIENTRY
_mesa_GetBufferParameteri64v(GLenum target, GLenum pname, GLint64 *params)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;
   GLint64 parameter;

   bufObj = get_buffer(ctx, "glGetBufferParameteri64v", target,
                       GL_INVALID_OPERATION);
   if (!bufObj)
      return;

   if (!get_buffer_parameter(ctx, bufObj, pname, &parameter,
                             "glGetBufferParameteri64v"))
      return; /* Error already recorded. */

   *params = parameter;
}

void GLAPIENTRY
_mesa_GetNamedBufferParameteriv(GLuint buffer, GLenum pname, GLint *params)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;
   GLint64 parameter;

   bufObj = _mesa_lookup_bufferobj_err(ctx, buffer,
                                       "glGetNamedBufferParameteriv");
   if (!bufObj)
      return;

   if (!get_buffer_parameter(ctx, bufObj, pname, &parameter,
                             "glGetNamedBufferParameteriv"))
      return; /* Error already recorded. */

   *params = (GLint) parameter;
}

void GLAPIENTRY
_mesa_GetNamedBufferParameteri64v(GLuint buffer, GLenum pname,
                                  GLint64 *params)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;
   GLint64 parameter;

   bufObj = _mesa_lookup_bufferobj_err(ctx, buffer,
                                       "glGetNamedBufferParameteri64v");
   if (!bufObj)
      return;

   if (!get_buffer_parameter(ctx, bufObj, pname, &parameter,
                             "glGetNamedBufferParameteri64v"))
      return; /* Error already recorded. */

   *params = parameter;
}


void GLAPIENTRY
_mesa_GetBufferPointerv(GLenum target, GLenum pname, GLvoid **params)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   if (pname != GL_BUFFER_MAP_POINTER) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glGetBufferPointerv(pname != "
                  "GL_BUFFER_MAP_POINTER)");
      return;
   }

   bufObj = get_buffer(ctx, "glGetBufferPointerv", target,
                       GL_INVALID_OPERATION);
   if (!bufObj)
      return;

   *params = bufObj->Mappings[MAP_USER].Pointer;
}

void GLAPIENTRY
_mesa_GetNamedBufferPointerv(GLuint buffer, GLenum pname, GLvoid **params)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   if (pname != GL_BUFFER_MAP_POINTER) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glGetNamedBufferPointerv(pname != "
                  "GL_BUFFER_MAP_POINTER)");
      return;
   }

   bufObj = _mesa_lookup_bufferobj_err(ctx, buffer,
                                       "glGetNamedBufferPointerv");
   if (!bufObj)
      return;

   *params = bufObj->Mappings[MAP_USER].Pointer;
}


static void
copy_buffer_sub_data(struct gl_context *ctx, struct gl_buffer_object *src,
                     struct gl_buffer_object *dst, GLintptr readOffset,
                     GLintptr writeOffset, GLsizeiptr size, const char *func)
{
   if (_mesa_check_disallowed_mapping(src)) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(readBuffer is mapped)", func);
      return;
   }

   if (_mesa_check_disallowed_mapping(dst)) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(writeBuffer is mapped)", func);
      return;
   }

   if (readOffset < 0) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(readOffset %d < 0)", func, (int) readOffset);
      return;
   }

   if (writeOffset < 0) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(writeOffset %d < 0)", func, (int) writeOffset);
      return;
   }

   if (size < 0) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(size %d < 0)", func, (int) size);
      return;
   }

   if (readOffset + size > src->Size) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(readOffset %d + size %d > src_buffer_size %d)", func,
                  (int) readOffset, (int) size, (int) src->Size);
      return;
   }

   if (writeOffset + size > dst->Size) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(writeOffset %d + size %d > dst_buffer_size %d)", func,
                  (int) writeOffset, (int) size, (int) dst->Size);
      return;
   }

   if (src == dst) {
      if (readOffset + size <= writeOffset) {
         /* OK */
      }
      else if (writeOffset + size <= readOffset) {
         /* OK */
      }
      else {
         /* overlapping src/dst is illegal */
         _mesa_error(ctx, GL_INVALID_VALUE,
                     "%s(overlapping src/dst)", func);
         return;
      }
   }

   dst->MinMaxCacheDirty = true;

   ctx->Driver.CopyBufferSubData(ctx, src, dst, readOffset, writeOffset, size);
}

void GLAPIENTRY
_mesa_CopyBufferSubData_no_error(GLenum readTarget, GLenum writeTarget,
                                 GLintptr readOffset, GLintptr writeOffset,
                                 GLsizeiptr size)
{
   GET_CURRENT_CONTEXT(ctx);

   struct gl_buffer_object **src_ptr = get_buffer_target(ctx, readTarget);
   struct gl_buffer_object *src = *src_ptr;

   struct gl_buffer_object **dst_ptr = get_buffer_target(ctx, writeTarget);
   struct gl_buffer_object *dst = *dst_ptr;

   dst->MinMaxCacheDirty = true;
   ctx->Driver.CopyBufferSubData(ctx, src, dst, readOffset, writeOffset,
                                 size);
}

void GLAPIENTRY
_mesa_CopyBufferSubData(GLenum readTarget, GLenum writeTarget,
                        GLintptr readOffset, GLintptr writeOffset,
                        GLsizeiptr size)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *src, *dst;

   src = get_buffer(ctx, "glCopyBufferSubData", readTarget,
                    GL_INVALID_OPERATION);
   if (!src)
      return;

   dst = get_buffer(ctx, "glCopyBufferSubData", writeTarget,
                    GL_INVALID_OPERATION);
   if (!dst)
      return;

   copy_buffer_sub_data(ctx, src, dst, readOffset, writeOffset, size,
                        "glCopyBufferSubData");
}

void GLAPIENTRY
_mesa_CopyNamedBufferSubData_no_error(GLuint readBuffer, GLuint writeBuffer,
                                      GLintptr readOffset,
                                      GLintptr writeOffset, GLsizeiptr size)
{
   GET_CURRENT_CONTEXT(ctx);

   struct gl_buffer_object *src = _mesa_lookup_bufferobj(ctx, readBuffer);
   struct gl_buffer_object *dst = _mesa_lookup_bufferobj(ctx, writeBuffer);

   dst->MinMaxCacheDirty = true;
   ctx->Driver.CopyBufferSubData(ctx, src, dst, readOffset, writeOffset,
                                 size);
}

void GLAPIENTRY
_mesa_CopyNamedBufferSubData(GLuint readBuffer, GLuint writeBuffer,
                             GLintptr readOffset, GLintptr writeOffset,
                             GLsizeiptr size)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *src, *dst;

   src = _mesa_lookup_bufferobj_err(ctx, readBuffer,
                                    "glCopyNamedBufferSubData");
   if (!src)
      return;

   dst = _mesa_lookup_bufferobj_err(ctx, writeBuffer,
                                    "glCopyNamedBufferSubData");
   if (!dst)
      return;

   copy_buffer_sub_data(ctx, src, dst, readOffset, writeOffset, size,
                        "glCopyNamedBufferSubData");
}

static bool
validate_map_buffer_range(struct gl_context *ctx,
                          struct gl_buffer_object *bufObj, GLintptr offset,
                          GLsizeiptr length, GLbitfield access,
                          const char *func)
{
   GLbitfield allowed_access;

   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, false);

   if (offset < 0) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(offset %ld < 0)", func, (long) offset);
      return false;
   }

   if (length < 0) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(length %ld < 0)", func, (long) length);
      return false;
   }

   /* Page 38 of the PDF of the OpenGL ES 3.0 spec says:
    *
    *     "An INVALID_OPERATION error is generated for any of the following
    *     conditions:
    *
    *     * <length> is zero."
    *
    * Additionally, page 94 of the PDF of the OpenGL 4.5 core spec
    * (30.10.2014) also says this, so it's no longer allowed for desktop GL,
    * either.
    */
   if (length == 0) {
      _mesa_error(ctx, GL_INVALID_OPERATION, "%s(length = 0)", func);
      return false;
   }

   allowed_access = GL_MAP_READ_BIT |
                    GL_MAP_WRITE_BIT |
                    GL_MAP_INVALIDATE_RANGE_BIT |
                    GL_MAP_INVALIDATE_BUFFER_BIT |
                    GL_MAP_FLUSH_EXPLICIT_BIT |
                    GL_MAP_UNSYNCHRONIZED_BIT;

   if (ctx->Extensions.ARB_buffer_storage) {
         allowed_access |= GL_MAP_PERSISTENT_BIT |
                           GL_MAP_COHERENT_BIT;
   }

   if (access & ~allowed_access) {
      /* generate an error if any bits other than those allowed are set */
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(access has undefined bits set)", func);
      return false;
   }

   if ((access & (GL_MAP_READ_BIT | GL_MAP_WRITE_BIT)) == 0) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(access indicates neither read or write)", func);
      return false;
   }

   if ((access & GL_MAP_READ_BIT) &&
       (access & (GL_MAP_INVALIDATE_RANGE_BIT |
                  GL_MAP_INVALIDATE_BUFFER_BIT |
                  GL_MAP_UNSYNCHRONIZED_BIT))) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(read access with disallowed bits)", func);
      return false;
   }

   if ((access & GL_MAP_FLUSH_EXPLICIT_BIT) &&
       ((access & GL_MAP_WRITE_BIT) == 0)) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(access has flush explicit without write)", func);
      return false;
   }

   if (access & GL_MAP_READ_BIT &&
       !(bufObj->StorageFlags & GL_MAP_READ_BIT)) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(buffer does not allow read access)", func);
      return false;
   }

   if (access & GL_MAP_WRITE_BIT &&
       !(bufObj->StorageFlags & GL_MAP_WRITE_BIT)) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(buffer does not allow write access)", func);
      return false;
   }

   if (access & GL_MAP_COHERENT_BIT &&
       !(bufObj->StorageFlags & GL_MAP_COHERENT_BIT)) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(buffer does not allow coherent access)", func);
      return false;
   }

   if (access & GL_MAP_PERSISTENT_BIT &&
       !(bufObj->StorageFlags & GL_MAP_PERSISTENT_BIT)) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(buffer does not allow persistent access)", func);
      return false;
   }

   if (offset + length > bufObj->Size) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(offset %lu + length %lu > buffer_size %lu)", func,
                  (unsigned long) offset, (unsigned long) length,
                  (unsigned long) bufObj->Size);
      return false;
   }

   if (_mesa_bufferobj_mapped(bufObj, MAP_USER)) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(buffer already mapped)", func);
      return false;
   }

   if (access & GL_MAP_WRITE_BIT) {
      bufObj->NumMapBufferWriteCalls++;
      if ((bufObj->Usage == GL_STATIC_DRAW ||
           bufObj->Usage == GL_STATIC_COPY) &&
          bufObj->NumMapBufferWriteCalls >= BUFFER_WARNING_CALL_COUNT) {
         BUFFER_USAGE_WARNING(ctx,
                              "using %s(buffer %u, offset %u, length %u) to "
                              "update a %s buffer",
                              func, bufObj->Name, offset, length,
                              _mesa_enum_to_string(bufObj->Usage));
      }
   }

   return true;
}

static void *
map_buffer_range(struct gl_context *ctx, struct gl_buffer_object *bufObj,
                 GLintptr offset, GLsizeiptr length, GLbitfield access,
                 const char *func)
{
   if (!bufObj->Size) {
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "%s(buffer size = 0)", func);
      return NULL;
   }

   assert(ctx->Driver.MapBufferRange);
   void *map = ctx->Driver.MapBufferRange(ctx, offset, length, access, bufObj,
                                          MAP_USER);
   if (!map) {
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "%s(map failed)", func);
   }
   else {
      /* The driver callback should have set all these fields.
       * This is important because other modules (like VBO) might call
       * the driver function directly.
       */
      assert(bufObj->Mappings[MAP_USER].Pointer == map);
      assert(bufObj->Mappings[MAP_USER].Length == length);
      assert(bufObj->Mappings[MAP_USER].Offset == offset);
      assert(bufObj->Mappings[MAP_USER].AccessFlags == access);
   }

   if (access & GL_MAP_WRITE_BIT) {
      bufObj->Written = GL_TRUE;
      bufObj->MinMaxCacheDirty = true;
   }

#ifdef VBO_DEBUG
   if (strstr(func, "Range") == NULL) { /* If not MapRange */
      printf("glMapBuffer(%u, sz %ld, access 0x%x)\n",
            bufObj->Name, bufObj->Size, access);
      /* Access must be write only */
      if ((access & GL_MAP_WRITE_BIT) && (!(access & ~GL_MAP_WRITE_BIT))) {
         GLuint i;
         GLubyte *b = (GLubyte *) bufObj->Pointer;
         for (i = 0; i < bufObj->Size; i++)
            b[i] = i & 0xff;
      }
   }
#endif

#ifdef BOUNDS_CHECK
   if (strstr(func, "Range") == NULL) { /* If not MapRange */
      GLubyte *buf = (GLubyte *) bufObj->Pointer;
      GLuint i;
      /* buffer is 100 bytes larger than requested, fill with magic value */
      for (i = 0; i < 100; i++) {
         buf[bufObj->Size - i - 1] = 123;
      }
   }
#endif

   return map;
}

void * GLAPIENTRY
_mesa_MapBufferRange_no_error(GLenum target, GLintptr offset,
                              GLsizeiptr length, GLbitfield access)
{
   GET_CURRENT_CONTEXT(ctx);

   struct gl_buffer_object **bufObjPtr = get_buffer_target(ctx, target);
   struct gl_buffer_object *bufObj = *bufObjPtr;

   return map_buffer_range(ctx, bufObj, offset, length, access,
                           "glMapBufferRange");
}

void * GLAPIENTRY
_mesa_MapBufferRange(GLenum target, GLintptr offset, GLsizeiptr length,
                     GLbitfield access)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   if (!ctx->Extensions.ARB_map_buffer_range) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "glMapBufferRange(ARB_map_buffer_range not supported)");
      return NULL;
   }

   bufObj = get_buffer(ctx, "glMapBufferRange", target, GL_INVALID_OPERATION);
   if (!bufObj)
      return NULL;

   if (!validate_map_buffer_range(ctx, bufObj, offset, length, access,
                                  "glMapBufferRange"))
      return NULL;

   return map_buffer_range(ctx, bufObj, offset, length, access,
                           "glMapBufferRange");
}

void * GLAPIENTRY
_mesa_MapNamedBufferRange_no_error(GLuint buffer, GLintptr offset,
                                   GLsizeiptr length, GLbitfield access)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj = _mesa_lookup_bufferobj(ctx, buffer);

   return map_buffer_range(ctx, bufObj, offset, length, access,
                           "glMapNamedBufferRange");
}

void * GLAPIENTRY
_mesa_MapNamedBufferRange(GLuint buffer, GLintptr offset, GLsizeiptr length,
                          GLbitfield access)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   if (!ctx->Extensions.ARB_map_buffer_range) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "glMapNamedBufferRange("
                  "ARB_map_buffer_range not supported)");
      return NULL;
   }

   bufObj = _mesa_lookup_bufferobj_err(ctx, buffer, "glMapNamedBufferRange");
   if (!bufObj)
      return NULL;

   if (!validate_map_buffer_range(ctx, bufObj, offset, length, access,
                                  "glMapNamedBufferRange"))
      return NULL;

   return map_buffer_range(ctx, bufObj, offset, length, access,
                           "glMapNamedBufferRange");
}

/**
 * Converts GLenum access from MapBuffer and MapNamedBuffer into
 * flags for input to map_buffer_range.
 *
 * \return true if the type of requested access is permissible.
 */
static bool
get_map_buffer_access_flags(struct gl_context *ctx, GLenum access,
                            GLbitfield *flags)
{
   switch (access) {
   case GL_READ_ONLY_ARB:
      *flags = GL_MAP_READ_BIT;
      return _mesa_is_desktop_gl(ctx);
   case GL_WRITE_ONLY_ARB:
      *flags = GL_MAP_WRITE_BIT;
      return true;
   case GL_READ_WRITE_ARB:
      *flags = GL_MAP_READ_BIT | GL_MAP_WRITE_BIT;
      return _mesa_is_desktop_gl(ctx);
   default:
      *flags = 0;
      return false;
   }
}

void * GLAPIENTRY
_mesa_MapBuffer_no_error(GLenum target, GLenum access)
{
   GET_CURRENT_CONTEXT(ctx);

   GLbitfield accessFlags;
   get_map_buffer_access_flags(ctx, access, &accessFlags);

   struct gl_buffer_object **bufObjPtr = get_buffer_target(ctx, target);
   struct gl_buffer_object *bufObj = *bufObjPtr;

   return map_buffer_range(ctx, bufObj, 0, bufObj->Size, accessFlags,
                           "glMapBuffer");
}

void * GLAPIENTRY
_mesa_MapBuffer(GLenum target, GLenum access)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;
   GLbitfield accessFlags;

   if (!get_map_buffer_access_flags(ctx, access, &accessFlags)) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glMapBuffer(invalid access)");
      return NULL;
   }

   bufObj = get_buffer(ctx, "glMapBuffer", target, GL_INVALID_OPERATION);
   if (!bufObj)
      return NULL;

   if (!validate_map_buffer_range(ctx, bufObj, 0, bufObj->Size, accessFlags,
                                  "glMapBuffer"))
      return NULL;

   return map_buffer_range(ctx, bufObj, 0, bufObj->Size, accessFlags,
                           "glMapBuffer");
}

void * GLAPIENTRY
_mesa_MapNamedBuffer_no_error(GLuint buffer, GLenum access)
{
   GET_CURRENT_CONTEXT(ctx);

   GLbitfield accessFlags;
   get_map_buffer_access_flags(ctx, access, &accessFlags);

   struct gl_buffer_object *bufObj = _mesa_lookup_bufferobj(ctx, buffer);

   return map_buffer_range(ctx, bufObj, 0, bufObj->Size, accessFlags,
                           "glMapNamedBuffer");
}

void * GLAPIENTRY
_mesa_MapNamedBuffer(GLuint buffer, GLenum access)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;
   GLbitfield accessFlags;

   if (!get_map_buffer_access_flags(ctx, access, &accessFlags)) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glMapNamedBuffer(invalid access)");
      return NULL;
   }

   bufObj = _mesa_lookup_bufferobj_err(ctx, buffer, "glMapNamedBuffer");
   if (!bufObj)
      return NULL;

   if (!validate_map_buffer_range(ctx, bufObj, 0, bufObj->Size, accessFlags,
                                  "glMapNamedBuffer"))
      return NULL;

   return map_buffer_range(ctx, bufObj, 0, bufObj->Size, accessFlags,
                           "glMapNamedBuffer");
}


static void
flush_mapped_buffer_range(struct gl_context *ctx,
                          struct gl_buffer_object *bufObj,
                          GLintptr offset, GLsizeiptr length,
                          const char *func)
{
   if (!ctx->Extensions.ARB_map_buffer_range) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(ARB_map_buffer_range not supported)", func);
      return;
   }

   if (offset < 0) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(offset %ld < 0)", func, (long) offset);
      return;
   }

   if (length < 0) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(length %ld < 0)", func, (long) length);
      return;
   }

   if (!_mesa_bufferobj_mapped(bufObj, MAP_USER)) {
      /* buffer is not mapped */
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(buffer is not mapped)", func);
      return;
   }

   if ((bufObj->Mappings[MAP_USER].AccessFlags &
        GL_MAP_FLUSH_EXPLICIT_BIT) == 0) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(GL_MAP_FLUSH_EXPLICIT_BIT not set)", func);
      return;
   }

   if (offset + length > bufObj->Mappings[MAP_USER].Length) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "%s(offset %ld + length %ld > mapped length %ld)", func,
                  (long) offset, (long) length,
                  (long) bufObj->Mappings[MAP_USER].Length);
      return;
   }

   assert(bufObj->Mappings[MAP_USER].AccessFlags & GL_MAP_WRITE_BIT);

   if (ctx->Driver.FlushMappedBufferRange)
      ctx->Driver.FlushMappedBufferRange(ctx, offset, length, bufObj,
                                         MAP_USER);
}

void GLAPIENTRY
_mesa_FlushMappedBufferRange_no_error(GLenum target, GLintptr offset,
                                      GLsizeiptr length)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object **bufObjPtr = get_buffer_target(ctx, target);
   struct gl_buffer_object *bufObj = *bufObjPtr;

   if (ctx->Driver.FlushMappedBufferRange)
      ctx->Driver.FlushMappedBufferRange(ctx, offset, length, bufObj,
                                         MAP_USER);
}

void GLAPIENTRY
_mesa_FlushMappedBufferRange(GLenum target, GLintptr offset,
                             GLsizeiptr length)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   bufObj = get_buffer(ctx, "glFlushMappedBufferRange", target,
                       GL_INVALID_OPERATION);
   if (!bufObj)
      return;

   flush_mapped_buffer_range(ctx, bufObj, offset, length,
                             "glFlushMappedBufferRange");
}

void GLAPIENTRY
_mesa_FlushMappedNamedBufferRange_no_error(GLuint buffer, GLintptr offset,
                                           GLsizeiptr length)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj = _mesa_lookup_bufferobj(ctx, buffer);

   if (ctx->Driver.FlushMappedBufferRange)
      ctx->Driver.FlushMappedBufferRange(ctx, offset, length, bufObj,
                                         MAP_USER);
}

void GLAPIENTRY
_mesa_FlushMappedNamedBufferRange(GLuint buffer, GLintptr offset,
                                  GLsizeiptr length)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   bufObj = _mesa_lookup_bufferobj_err(ctx, buffer,
                                       "glFlushMappedNamedBufferRange");
   if (!bufObj)
      return;

   flush_mapped_buffer_range(ctx, bufObj, offset, length,
                             "glFlushMappedNamedBufferRange");
}

static void
bind_buffer_range_uniform_buffer(struct gl_context *ctx, GLuint index,
                                 struct gl_buffer_object *bufObj,
                                 GLintptr offset, GLsizeiptr size)
{
   if (bufObj == ctx->Shared->NullBufferObj) {
      offset = -1;
      size = -1;
   }

   _mesa_reference_buffer_object(ctx, &ctx->UniformBuffer, bufObj);
   bind_uniform_buffer(ctx, index, bufObj, offset, size, GL_FALSE);
}

/**
 * Bind a region of a buffer object to a uniform block binding point.
 * \param index  the uniform buffer binding point index
 * \param bufObj  the buffer object
 * \param offset  offset to the start of buffer object region
 * \param size  size of the buffer object region
 */
static void
bind_buffer_range_uniform_buffer_err(struct gl_context *ctx, GLuint index,
                                     struct gl_buffer_object *bufObj,
                                     GLintptr offset, GLsizeiptr size)
{
   if (index >= ctx->Const.MaxUniformBufferBindings) {
      _mesa_error(ctx, GL_INVALID_VALUE, "glBindBufferRange(index=%d)", index);
      return;
   }

   if (offset & (ctx->Const.UniformBufferOffsetAlignment - 1)) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "glBindBufferRange(offset misaligned %d/%d)", (int) offset,
		  ctx->Const.UniformBufferOffsetAlignment);
      return;
   }

   bind_buffer_range_uniform_buffer(ctx, index, bufObj, offset, size);
}

static void
bind_buffer_range_shader_storage_buffer(struct gl_context *ctx,
                                        GLuint index,
                                        struct gl_buffer_object *bufObj,
                                        GLintptr offset,
                                        GLsizeiptr size)
{
   if (bufObj == ctx->Shared->NullBufferObj) {
      offset = -1;
      size = -1;
   }

   _mesa_reference_buffer_object(ctx, &ctx->ShaderStorageBuffer, bufObj);
   bind_shader_storage_buffer(ctx, index, bufObj, offset, size, GL_FALSE);
}

/**
 * Bind a region of a buffer object to a shader storage block binding point.
 * \param index  the shader storage buffer binding point index
 * \param bufObj  the buffer object
 * \param offset  offset to the start of buffer object region
 * \param size  size of the buffer object region
 */
static void
bind_buffer_range_shader_storage_buffer_err(struct gl_context *ctx,
                                            GLuint index,
                                            struct gl_buffer_object *bufObj,
                                            GLintptr offset, GLsizeiptr size)
{
   if (index >= ctx->Const.MaxShaderStorageBufferBindings) {
      _mesa_error(ctx, GL_INVALID_VALUE, "glBindBufferRange(index=%d)", index);
      return;
   }

   if (offset & (ctx->Const.ShaderStorageBufferOffsetAlignment - 1)) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "glBindBufferRange(offset misaligned %d/%d)", (int) offset,
                  ctx->Const.ShaderStorageBufferOffsetAlignment);
      return;
   }

   bind_buffer_range_shader_storage_buffer(ctx, index, bufObj, offset, size);
}

static void
bind_buffer_range_atomic_buffer(struct gl_context *ctx, GLuint index,
                                 struct gl_buffer_object *bufObj,
                                 GLintptr offset, GLsizeiptr size)
{
   if (bufObj == ctx->Shared->NullBufferObj) {
      offset = -1;
      size = -1;
   }

   _mesa_reference_buffer_object(ctx, &ctx->AtomicBuffer, bufObj);
   bind_atomic_buffer(ctx, index, bufObj, offset, size, GL_FALSE);
}

/**
 * Bind a region of a buffer object to an atomic storage block binding point.
 * \param index  the shader storage buffer binding point index
 * \param bufObj  the buffer object
 * \param offset  offset to the start of buffer object region
 * \param size  size of the buffer object region
 */
static void
bind_buffer_range_atomic_buffer_err(struct gl_context *ctx,
                                    GLuint index,
                                    struct gl_buffer_object *bufObj,
                                    GLintptr offset, GLsizeiptr size)
{
   if (index >= ctx->Const.MaxAtomicBufferBindings) {
      _mesa_error(ctx, GL_INVALID_VALUE, "glBindBufferRange(index=%d)", index);
      return;
   }

   if (offset & (ATOMIC_COUNTER_SIZE - 1)) {
      _mesa_error(ctx, GL_INVALID_VALUE,
		  "glBindBufferRange(offset misaligned %d/%d)", (int) offset,
		  ATOMIC_COUNTER_SIZE);
      return;
   }

   bind_buffer_range_atomic_buffer(ctx, index, bufObj, offset, size);
}

static inline bool
bind_buffers_check_offset_and_size(struct gl_context *ctx,
                                   GLuint index,
                                   const GLintptr *offsets,
                                   const GLsizeiptr *sizes)
{
   if (offsets[index] < 0) {
      /* The ARB_multi_bind spec says:
       *
       *    "An INVALID_VALUE error is generated by BindBuffersRange if any
       *     value in <offsets> is less than zero (per binding)."
       */
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "glBindBuffersRange(offsets[%u]=%" PRId64 " < 0)",
                  index, (int64_t) offsets[index]);
      return false;
   }

   if (sizes[index] <= 0) {
      /* The ARB_multi_bind spec says:
       *
       *     "An INVALID_VALUE error is generated by BindBuffersRange if any
       *      value in <sizes> is less than or equal to zero (per binding)."
       */
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "glBindBuffersRange(sizes[%u]=%" PRId64 " <= 0)",
                  index, (int64_t) sizes[index]);
      return false;
   }

   return true;
}

static bool
error_check_bind_uniform_buffers(struct gl_context *ctx,
                                 GLuint first, GLsizei count,
                                 const char *caller)
{
   if (!ctx->Extensions.ARB_uniform_buffer_object) {
      _mesa_error(ctx, GL_INVALID_ENUM,
                  "%s(target=GL_UNIFORM_BUFFER)", caller);
      return false;
   }

   /* The ARB_multi_bind_spec says:
    *
    *     "An INVALID_OPERATION error is generated if <first> + <count> is
    *      greater than the number of target-specific indexed binding points,
    *      as described in section 6.7.1."
    */
   if (first + count > ctx->Const.MaxUniformBufferBindings) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(first=%u + count=%d > the value of "
                  "GL_MAX_UNIFORM_BUFFER_BINDINGS=%u)",
                  caller, first, count,
                  ctx->Const.MaxUniformBufferBindings);
      return false;
   }

   return true;
}

static bool
error_check_bind_shader_storage_buffers(struct gl_context *ctx,
                                        GLuint first, GLsizei count,
                                        const char *caller)
{
   if (!ctx->Extensions.ARB_shader_storage_buffer_object) {
      _mesa_error(ctx, GL_INVALID_ENUM,
                  "%s(target=GL_SHADER_STORAGE_BUFFER)", caller);
      return false;
   }

   /* The ARB_multi_bind_spec says:
    *
    *     "An INVALID_OPERATION error is generated if <first> + <count> is
    *      greater than the number of target-specific indexed binding points,
    *      as described in section 6.7.1."
    */
   if (first + count > ctx->Const.MaxShaderStorageBufferBindings) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(first=%u + count=%d > the value of "
                  "GL_MAX_SHADER_STORAGE_BUFFER_BINDINGS=%u)",
                  caller, first, count,
                  ctx->Const.MaxShaderStorageBufferBindings);
      return false;
   }

   return true;
}

/**
 * Unbind all uniform buffers in the range
 * <first> through <first>+<count>-1
 */
static void
unbind_uniform_buffers(struct gl_context *ctx, GLuint first, GLsizei count)
{
   struct gl_buffer_object *bufObj = ctx->Shared->NullBufferObj;

   for (int i = 0; i < count; i++)
      set_buffer_binding(ctx, &ctx->UniformBufferBindings[first + i],
                         bufObj, -1, -1, GL_TRUE, 0);
}

/**
 * Unbind all shader storage buffers in the range
 * <first> through <first>+<count>-1
 */
static void
unbind_shader_storage_buffers(struct gl_context *ctx, GLuint first,
                              GLsizei count)
{
   struct gl_buffer_object *bufObj = ctx->Shared->NullBufferObj;

   for (int i = 0; i < count; i++)
      set_buffer_binding(ctx, &ctx->ShaderStorageBufferBindings[first + i],
                         bufObj, -1, -1, GL_TRUE, 0);
}

static void
bind_uniform_buffers(struct gl_context *ctx, GLuint first, GLsizei count,
                     const GLuint *buffers,
                     bool range,
                     const GLintptr *offsets, const GLsizeiptr *sizes,
                     const char *caller)
{
   if (!error_check_bind_uniform_buffers(ctx, first, count, caller))
      return;

   /* Assume that at least one binding will be changed */
   FLUSH_VERTICES(ctx, 0);
   ctx->NewDriverState |= ctx->DriverFlags.NewUniformBuffer;

   if (!buffers) {
      /* The ARB_multi_bind spec says:
       *
       *    "If <buffers> is NULL, all bindings from <first> through
       *     <first>+<count>-1 are reset to their unbound (zero) state.
       *     In this case, the offsets and sizes associated with the
       *     binding points are set to default values, ignoring
       *     <offsets> and <sizes>."
       */
      unbind_uniform_buffers(ctx, first, count);
      return;
   }

   /* Note that the error semantics for multi-bind commands differ from
    * those of other GL commands.
    *
    * The Issues section in the ARB_multi_bind spec says:
    *
    *    "(11) Typically, OpenGL specifies that if an error is generated by a
    *          command, that command has no effect.  This is somewhat
    *          unfortunate for multi-bind commands, because it would require a
    *          first pass to scan the entire list of bound objects for errors
    *          and then a second pass to actually perform the bindings.
    *          Should we have different error semantics?
    *
    *       RESOLVED:  Yes.  In this specification, when the parameters for
    *       one of the <count> binding points are invalid, that binding point
    *       is not updated and an error will be generated.  However, other
    *       binding points in the same command will be updated if their
    *       parameters are valid and no other error occurs."
    */

   _mesa_HashLockMutex(ctx->Shared->BufferObjects);

   for (int i = 0; i < count; i++) {
      struct gl_buffer_binding *binding =
         &ctx->UniformBufferBindings[first + i];
      GLintptr offset = 0;
      GLsizeiptr size = 0;

      if (range) {
         if (!bind_buffers_check_offset_and_size(ctx, i, offsets, sizes))
            continue;

         /* The ARB_multi_bind spec says:
          *
          *     "An INVALID_VALUE error is generated by BindBuffersRange if any
          *      pair of values in <offsets> and <sizes> does not respectively
          *      satisfy the constraints described for those parameters for the
          *      specified target, as described in section 6.7.1 (per binding)."
          *
          * Section 6.7.1 refers to table 6.5, which says:
          *
          *     "┌───────────────────────────────────────────────────────────────┐
          *      │ Uniform buffer array bindings (see sec. 7.6)                  │
          *      ├─────────────────────┬─────────────────────────────────────────┤
          *      │  ...                │  ...                                    │
          *      │  offset restriction │  multiple of value of UNIFORM_BUFFER_-  │
          *      │                     │  OFFSET_ALIGNMENT                       │
          *      │  ...                │  ...                                    │
          *      │  size restriction   │  none                                   │
          *      └─────────────────────┴─────────────────────────────────────────┘"
          */
         if (offsets[i] & (ctx->Const.UniformBufferOffsetAlignment - 1)) {
            _mesa_error(ctx, GL_INVALID_VALUE,
                        "glBindBuffersRange(offsets[%u]=%" PRId64
                        " is misaligned; it must be a multiple of the value of "
                        "GL_UNIFORM_BUFFER_OFFSET_ALIGNMENT=%u when "
                        "target=GL_UNIFORM_BUFFER)",
                        i, (int64_t) offsets[i],
                        ctx->Const.UniformBufferOffsetAlignment);
            continue;
         }

         offset = offsets[i];
         size = sizes[i];
      }

      set_buffer_multi_binding(ctx, buffers, i, caller,
                               binding, offset, size, range,
                               USAGE_UNIFORM_BUFFER);
   }

   _mesa_HashUnlockMutex(ctx->Shared->BufferObjects);
}

static void
bind_shader_storage_buffers(struct gl_context *ctx, GLuint first,
                            GLsizei count, const GLuint *buffers,
                            bool range,
                            const GLintptr *offsets,
                            const GLsizeiptr *sizes,
                            const char *caller)
{
   if (!error_check_bind_shader_storage_buffers(ctx, first, count, caller))
      return;

   /* Assume that at least one binding will be changed */
   FLUSH_VERTICES(ctx, 0);
   ctx->NewDriverState |= ctx->DriverFlags.NewShaderStorageBuffer;

   if (!buffers) {
      /* The ARB_multi_bind spec says:
       *
       *    "If <buffers> is NULL, all bindings from <first> through
       *     <first>+<count>-1 are reset to their unbound (zero) state.
       *     In this case, the offsets and sizes associated with the
       *     binding points are set to default values, ignoring
       *     <offsets> and <sizes>."
       */
      unbind_shader_storage_buffers(ctx, first, count);
      return;
   }

   /* Note that the error semantics for multi-bind commands differ from
    * those of other GL commands.
    *
    * The Issues section in the ARB_multi_bind spec says:
    *
    *    "(11) Typically, OpenGL specifies that if an error is generated by a
    *          command, that command has no effect.  This is somewhat
    *          unfortunate for multi-bind commands, because it would require a
    *          first pass to scan the entire list of bound objects for errors
    *          and then a second pass to actually perform the bindings.
    *          Should we have different error semantics?
    *
    *       RESOLVED:  Yes.  In this specification, when the parameters for
    *       one of the <count> binding points are invalid, that binding point
    *       is not updated and an error will be generated.  However, other
    *       binding points in the same command will be updated if their
    *       parameters are valid and no other error occurs."
    */

   _mesa_HashLockMutex(ctx->Shared->BufferObjects);

   for (int i = 0; i < count; i++) {
      struct gl_buffer_binding *binding =
         &ctx->ShaderStorageBufferBindings[first + i];
      GLintptr offset = 0;
      GLsizeiptr size = 0;

      if (range) {
         if (!bind_buffers_check_offset_and_size(ctx, i, offsets, sizes))
            continue;

         /* The ARB_multi_bind spec says:
         *
         *     "An INVALID_VALUE error is generated by BindBuffersRange if any
         *      pair of values in <offsets> and <sizes> does not respectively
         *      satisfy the constraints described for those parameters for the
         *      specified target, as described in section 6.7.1 (per binding)."
         *
         * Section 6.7.1 refers to table 6.5, which says:
         *
         *     "┌───────────────────────────────────────────────────────────────┐
         *      │ Shader storage buffer array bindings (see sec. 7.8)           │
         *      ├─────────────────────┬─────────────────────────────────────────┤
         *      │  ...                │  ...                                    │
         *      │  offset restriction │  multiple of value of SHADER_STORAGE_-  │
         *      │                     │  BUFFER_OFFSET_ALIGNMENT                │
         *      │  ...                │  ...                                    │
         *      │  size restriction   │  none                                   │
         *      └─────────────────────┴─────────────────────────────────────────┘"
         */
         if (offsets[i] & (ctx->Const.ShaderStorageBufferOffsetAlignment - 1)) {
            _mesa_error(ctx, GL_INVALID_VALUE,
                        "glBindBuffersRange(offsets[%u]=%" PRId64
                        " is misaligned; it must be a multiple of the value of "
                        "GL_SHADER_STORAGE_BUFFER_OFFSET_ALIGNMENT=%u when "
                        "target=GL_SHADER_STORAGE_BUFFER)",
                        i, (int64_t) offsets[i],
                        ctx->Const.ShaderStorageBufferOffsetAlignment);
            continue;
         }

         offset = offsets[i];
         size = sizes[i];
      }

      set_buffer_multi_binding(ctx, buffers, i, caller,
                               binding, offset, size, range,
                               USAGE_SHADER_STORAGE_BUFFER);
   }

   _mesa_HashUnlockMutex(ctx->Shared->BufferObjects);
}

static bool
error_check_bind_xfb_buffers(struct gl_context *ctx,
                             struct gl_transform_feedback_object *tfObj,
                             GLuint first, GLsizei count, const char *caller)
{
   if (!ctx->Extensions.EXT_transform_feedback) {
      _mesa_error(ctx, GL_INVALID_ENUM,
                  "%s(target=GL_TRANSFORM_FEEDBACK_BUFFER)", caller);
      return false;
   }

   /* Page 398 of the PDF of the OpenGL 4.4 (Core Profile) spec says:
    *
    *     "An INVALID_OPERATION error is generated :
    *
    *     ...
    *     • by BindBufferRange or BindBufferBase if target is TRANSFORM_-
    *       FEEDBACK_BUFFER and transform feedback is currently active."
    *
    * We assume that this is also meant to apply to BindBuffersRange
    * and BindBuffersBase.
    */
   if (tfObj->Active) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(Changing transform feedback buffers while "
                  "transform feedback is active)", caller);
      return false;
   }

   /* The ARB_multi_bind_spec says:
    *
    *     "An INVALID_OPERATION error is generated if <first> + <count> is
    *      greater than the number of target-specific indexed binding points,
    *      as described in section 6.7.1."
    */
   if (first + count > ctx->Const.MaxTransformFeedbackBuffers) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(first=%u + count=%d > the value of "
                  "GL_MAX_TRANSFORM_FEEDBACK_BUFFERS=%u)",
                  caller, first, count,
                  ctx->Const.MaxTransformFeedbackBuffers);
      return false;
   }

   return true;
}

/**
 * Unbind all transform feedback buffers in the range
 * <first> through <first>+<count>-1
 */
static void
unbind_xfb_buffers(struct gl_context *ctx,
                   struct gl_transform_feedback_object *tfObj,
                   GLuint first, GLsizei count)
{
   struct gl_buffer_object * const bufObj = ctx->Shared->NullBufferObj;

   for (int i = 0; i < count; i++)
      _mesa_set_transform_feedback_binding(ctx, tfObj, first + i,
                                           bufObj, 0, 0);
}

static void
bind_xfb_buffers(struct gl_context *ctx,
                 GLuint first, GLsizei count,
                 const GLuint *buffers,
                 bool range,
                 const GLintptr *offsets,
                 const GLsizeiptr *sizes,
                 const char *caller)
{
   struct gl_transform_feedback_object *tfObj =
       ctx->TransformFeedback.CurrentObject;

   if (!error_check_bind_xfb_buffers(ctx, tfObj, first, count, caller))
      return;

   /* Assume that at least one binding will be changed */
   FLUSH_VERTICES(ctx, 0);
   ctx->NewDriverState |= ctx->DriverFlags.NewTransformFeedback;

   if (!buffers) {
      /* The ARB_multi_bind spec says:
       *
       *    "If <buffers> is NULL, all bindings from <first> through
       *     <first>+<count>-1 are reset to their unbound (zero) state.
       *     In this case, the offsets and sizes associated with the
       *     binding points are set to default values, ignoring
       *     <offsets> and <sizes>."
       */
      unbind_xfb_buffers(ctx, tfObj, first, count);
      return;
   }

   /* Note that the error semantics for multi-bind commands differ from
    * those of other GL commands.
    *
    * The Issues section in the ARB_multi_bind spec says:
    *
    *    "(11) Typically, OpenGL specifies that if an error is generated by a
    *          command, that command has no effect.  This is somewhat
    *          unfortunate for multi-bind commands, because it would require a
    *          first pass to scan the entire list of bound objects for errors
    *          and then a second pass to actually perform the bindings.
    *          Should we have different error semantics?
    *
    *       RESOLVED:  Yes.  In this specification, when the parameters for
    *       one of the <count> binding points are invalid, that binding point
    *       is not updated and an error will be generated.  However, other
    *       binding points in the same command will be updated if their
    *       parameters are valid and no other error occurs."
    */

   _mesa_HashLockMutex(ctx->Shared->BufferObjects);

   for (int i = 0; i < count; i++) {
      const GLuint index = first + i;
      struct gl_buffer_object * const boundBufObj = tfObj->Buffers[index];
      struct gl_buffer_object *bufObj;
      GLintptr offset = 0;
      GLsizeiptr size = 0;

      if (range) {
         if (!bind_buffers_check_offset_and_size(ctx, i, offsets, sizes))
            continue;

         /* The ARB_multi_bind spec says:
          *
          *     "An INVALID_VALUE error is generated by BindBuffersRange if any
          *      pair of values in <offsets> and <sizes> does not respectively
          *      satisfy the constraints described for those parameters for the
          *      specified target, as described in section 6.7.1 (per binding)."
          *
          * Section 6.7.1 refers to table 6.5, which says:
          *
          *     "┌───────────────────────────────────────────────────────────────┐
          *      │ Transform feedback array bindings (see sec. 13.2.2)           │
          *      ├───────────────────────┬───────────────────────────────────────┤
          *      │    ...                │    ...                                │
          *      │    offset restriction │    multiple of 4                      │
          *      │    ...                │    ...                                │
          *      │    size restriction   │    multiple of 4                      │
          *      └───────────────────────┴───────────────────────────────────────┘"
          */
         if (offsets[i] & 0x3) {
            _mesa_error(ctx, GL_INVALID_VALUE,
                        "glBindBuffersRange(offsets[%u]=%" PRId64
                        " is misaligned; it must be a multiple of 4 when "
                        "target=GL_TRANSFORM_FEEDBACK_BUFFER)",
                        i, (int64_t) offsets[i]);
            continue;
         }

         if (sizes[i] & 0x3) {
            _mesa_error(ctx, GL_INVALID_VALUE,
                        "glBindBuffersRange(sizes[%u]=%" PRId64
                        " is misaligned; it must be a multiple of 4 when "
                        "target=GL_TRANSFORM_FEEDBACK_BUFFER)",
                        i, (int64_t) sizes[i]);
            continue;
         }

         offset = offsets[i];
         size = sizes[i];
      }

      if (boundBufObj && boundBufObj->Name == buffers[i])
         bufObj = boundBufObj;
      else
         bufObj = _mesa_multi_bind_lookup_bufferobj(ctx, buffers, i, caller);

      if (bufObj)
         _mesa_set_transform_feedback_binding(ctx, tfObj, index, bufObj,
                                              offset, size);
   }

   _mesa_HashUnlockMutex(ctx->Shared->BufferObjects);
}

static bool
error_check_bind_atomic_buffers(struct gl_context *ctx,
                                GLuint first, GLsizei count,
                                const char *caller)
{
   if (!ctx->Extensions.ARB_shader_atomic_counters) {
      _mesa_error(ctx, GL_INVALID_ENUM,
                  "%s(target=GL_ATOMIC_COUNTER_BUFFER)", caller);
      return false;
   }

   /* The ARB_multi_bind_spec says:
    *
    *     "An INVALID_OPERATION error is generated if <first> + <count> is
    *      greater than the number of target-specific indexed binding points,
    *      as described in section 6.7.1."
    */
   if (first + count > ctx->Const.MaxAtomicBufferBindings) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "%s(first=%u + count=%d > the value of "
                  "GL_MAX_ATOMIC_BUFFER_BINDINGS=%u)",
                  caller, first, count, ctx->Const.MaxAtomicBufferBindings);
      return false;
   }

   return true;
}

/**
 * Unbind all atomic counter buffers in the range
 * <first> through <first>+<count>-1
 */
static void
unbind_atomic_buffers(struct gl_context *ctx, GLuint first, GLsizei count)
{
   struct gl_buffer_object * const bufObj = ctx->Shared->NullBufferObj;

   for (int i = 0; i < count; i++)
      set_buffer_binding(ctx, &ctx->AtomicBufferBindings[first + i],
                         bufObj, -1, -1, GL_TRUE, 0);
}

static void
bind_atomic_buffers(struct gl_context *ctx,
                    GLuint first,
                    GLsizei count,
                    const GLuint *buffers,
                    bool range,
                    const GLintptr *offsets,
                    const GLsizeiptr *sizes,
                    const char *caller)
{
   if (!error_check_bind_atomic_buffers(ctx, first, count, caller))
     return;

   /* Assume that at least one binding will be changed */
   FLUSH_VERTICES(ctx, 0);
   ctx->NewDriverState |= ctx->DriverFlags.NewAtomicBuffer;

   if (!buffers) {
      /* The ARB_multi_bind spec says:
       *
       *    "If <buffers> is NULL, all bindings from <first> through
       *     <first>+<count>-1 are reset to their unbound (zero) state.
       *     In this case, the offsets and sizes associated with the
       *     binding points are set to default values, ignoring
       *     <offsets> and <sizes>."
       */
      unbind_atomic_buffers(ctx, first, count);
      return;
   }

   /* Note that the error semantics for multi-bind commands differ from
    * those of other GL commands.
    *
    * The Issues section in the ARB_multi_bind spec says:
    *
    *    "(11) Typically, OpenGL specifies that if an error is generated by a
    *          command, that command has no effect.  This is somewhat
    *          unfortunate for multi-bind commands, because it would require a
    *          first pass to scan the entire list of bound objects for errors
    *          and then a second pass to actually perform the bindings.
    *          Should we have different error semantics?
    *
    *       RESOLVED:  Yes.  In this specification, when the parameters for
    *       one of the <count> binding points are invalid, that binding point
    *       is not updated and an error will be generated.  However, other
    *       binding points in the same command will be updated if their
    *       parameters are valid and no other error occurs."
    */

   _mesa_HashLockMutex(ctx->Shared->BufferObjects);

   for (int i = 0; i < count; i++) {
      struct gl_buffer_binding *binding =
         &ctx->AtomicBufferBindings[first + i];
      GLintptr offset = 0;
      GLsizeiptr size = 0;

      if (range) {
         if (!bind_buffers_check_offset_and_size(ctx, i, offsets, sizes))
            continue;

         /* The ARB_multi_bind spec says:
          *
          *     "An INVALID_VALUE error is generated by BindBuffersRange if any
          *      pair of values in <offsets> and <sizes> does not respectively
          *      satisfy the constraints described for those parameters for the
          *      specified target, as described in section 6.7.1 (per binding)."
          *
          * Section 6.7.1 refers to table 6.5, which says:
          *
          *     "┌───────────────────────────────────────────────────────────────┐
          *      │ Atomic counter array bindings (see sec. 7.7.2)                │
          *      ├───────────────────────┬───────────────────────────────────────┤
          *      │    ...                │    ...                                │
          *      │    offset restriction │    multiple of 4                      │
          *      │    ...                │    ...                                │
          *      │    size restriction   │    none                               │
          *      └───────────────────────┴───────────────────────────────────────┘"
          */
         if (offsets[i] & (ATOMIC_COUNTER_SIZE - 1)) {
            _mesa_error(ctx, GL_INVALID_VALUE,
                        "glBindBuffersRange(offsets[%u]=%" PRId64
                        " is misaligned; it must be a multiple of %d when "
                        "target=GL_ATOMIC_COUNTER_BUFFER)",
                        i, (int64_t) offsets[i], ATOMIC_COUNTER_SIZE);
            continue;
         }

         offset = offsets[i];
         size = sizes[i];
      }

      set_buffer_multi_binding(ctx, buffers, i, caller,
                               binding, offset, size, range,
                               USAGE_ATOMIC_COUNTER_BUFFER);
   }

   _mesa_HashUnlockMutex(ctx->Shared->BufferObjects);
}

static ALWAYS_INLINE void
bind_buffer_range(GLenum target, GLuint index, GLuint buffer, GLintptr offset,
                  GLsizeiptr size, bool no_error)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   if (MESA_VERBOSE & VERBOSE_API) {
      _mesa_debug(ctx, "glBindBufferRange(%s, %u, %u, %lu, %lu)\n",
                  _mesa_enum_to_string(target), index, buffer,
                  (unsigned long) offset, (unsigned long) size);
   }

   if (buffer == 0) {
      bufObj = ctx->Shared->NullBufferObj;
   } else {
      bufObj = _mesa_lookup_bufferobj(ctx, buffer);
      if (!_mesa_handle_bind_buffer_gen(ctx, buffer,
                                        &bufObj, "glBindBufferRange"))
         return;

      if (!no_error && !bufObj) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "glBindBufferRange(invalid buffer=%u)", buffer);
         return;
      }
   }

   if (no_error) {
      switch (target) {
      case GL_TRANSFORM_FEEDBACK_BUFFER:
         _mesa_bind_buffer_range_xfb(ctx, ctx->TransformFeedback.CurrentObject,
                                     index, bufObj, offset, size);
         return;
      case GL_UNIFORM_BUFFER:
         bind_buffer_range_uniform_buffer(ctx, index, bufObj, offset, size);
         return;
      case GL_SHADER_STORAGE_BUFFER:
         bind_buffer_range_shader_storage_buffer(ctx, index, bufObj, offset,
                                                 size);
         return;
      case GL_ATOMIC_COUNTER_BUFFER:
         bind_buffer_range_atomic_buffer(ctx, index, bufObj, offset, size);
         return;
      default:
         unreachable("invalid BindBufferRange target with KHR_no_error");
      }
   } else {
      if (buffer != 0) {
         if (size <= 0) {
            _mesa_error(ctx, GL_INVALID_VALUE, "glBindBufferRange(size=%d)",
                        (int) size);
            return;
         }
      }

      switch (target) {
      case GL_TRANSFORM_FEEDBACK_BUFFER:
         if (!_mesa_validate_buffer_range_xfb(ctx,
                                              ctx->TransformFeedback.CurrentObject,
                                              index, bufObj, offset, size,
                                              false))
            return;

         _mesa_bind_buffer_range_xfb(ctx, ctx->TransformFeedback.CurrentObject,
                                     index, bufObj, offset, size);
         return;
      case GL_UNIFORM_BUFFER:
         bind_buffer_range_uniform_buffer_err(ctx, index, bufObj, offset,
                                              size);
         return;
      case GL_SHADER_STORAGE_BUFFER:
         bind_buffer_range_shader_storage_buffer_err(ctx, index, bufObj,
                                                     offset, size);
         return;
      case GL_ATOMIC_COUNTER_BUFFER:
         bind_buffer_range_atomic_buffer_err(ctx, index, bufObj,
                                             offset, size);
         return;
      default:
         _mesa_error(ctx, GL_INVALID_ENUM, "glBindBufferRange(target)");
         return;
      }
   }
}

void GLAPIENTRY
_mesa_BindBufferRange_no_error(GLenum target, GLuint index, GLuint buffer,
                               GLintptr offset, GLsizeiptr size)
{
   bind_buffer_range(target, index, buffer, offset, size, true);
}

void GLAPIENTRY
_mesa_BindBufferRange(GLenum target, GLuint index,
                      GLuint buffer, GLintptr offset, GLsizeiptr size)
{
   bind_buffer_range(target, index, buffer, offset, size, false);
}

void GLAPIENTRY
_mesa_BindBufferBase(GLenum target, GLuint index, GLuint buffer)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   if (MESA_VERBOSE & VERBOSE_API) {
      _mesa_debug(ctx, "glBindBufferBase(%s, %u, %u)\n",
                  _mesa_enum_to_string(target), index, buffer);
   }

   if (buffer == 0) {
      bufObj = ctx->Shared->NullBufferObj;
   } else {
      bufObj = _mesa_lookup_bufferobj(ctx, buffer);
      if (!_mesa_handle_bind_buffer_gen(ctx, buffer,
                                        &bufObj, "glBindBufferBase"))
         return;

      if (!bufObj) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "glBindBufferBase(invalid buffer=%u)", buffer);
         return;
      }
   }

   /* Note that there's some oddness in the GL 3.1-GL 3.3 specifications with
    * regards to BindBufferBase.  It says (GL 3.1 core spec, page 63):
    *
    *     "BindBufferBase is equivalent to calling BindBufferRange with offset
    *      zero and size equal to the size of buffer."
    *
    * but it says for glGetIntegeri_v (GL 3.1 core spec, page 230):
    *
    *     "If the parameter (starting offset or size) was not specified when the
    *      buffer object was bound, zero is returned."
    *
    * What happens if the size of the buffer changes?  Does the size of the
    * buffer at the moment glBindBufferBase was called still play a role, like
    * the first quote would imply, or is the size meaningless in the
    * glBindBufferBase case like the second quote would suggest?  The GL 4.1
    * core spec page 45 says:
    *
    *     "It is equivalent to calling BindBufferRange with offset zero, while
    *      size is determined by the size of the bound buffer at the time the
    *      binding is used."
    *
    * My interpretation is that the GL 4.1 spec was a clarification of the
    * behavior, not a change.  In particular, this choice will only make
    * rendering work in cases where it would have had undefined results.
    */

   switch (target) {
   case GL_TRANSFORM_FEEDBACK_BUFFER:
      _mesa_bind_buffer_base_transform_feedback(ctx,
                                                ctx->TransformFeedback.CurrentObject,
                                                index, bufObj, false);
      return;
   case GL_UNIFORM_BUFFER:
      bind_buffer_base_uniform_buffer(ctx, index, bufObj);
      return;
   case GL_SHADER_STORAGE_BUFFER:
      bind_buffer_base_shader_storage_buffer(ctx, index, bufObj);
      return;
   case GL_ATOMIC_COUNTER_BUFFER:
      bind_buffer_base_atomic_buffer(ctx, index, bufObj);
      return;
   default:
      _mesa_error(ctx, GL_INVALID_ENUM, "glBindBufferBase(target)");
      return;
   }
}

void GLAPIENTRY
_mesa_BindBuffersRange(GLenum target, GLuint first, GLsizei count,
                       const GLuint *buffers,
                       const GLintptr *offsets, const GLsizeiptr *sizes)
{
   GET_CURRENT_CONTEXT(ctx);

   if (MESA_VERBOSE & VERBOSE_API) {
      _mesa_debug(ctx, "glBindBuffersRange(%s, %u, %d, %p, %p, %p)\n",
                  _mesa_enum_to_string(target), first, count,
                  buffers, offsets, sizes);
   }

   switch (target) {
   case GL_TRANSFORM_FEEDBACK_BUFFER:
      bind_xfb_buffers(ctx, first, count, buffers, true, offsets, sizes,
                       "glBindBuffersRange");
      return;
   case GL_UNIFORM_BUFFER:
      bind_uniform_buffers(ctx, first, count, buffers, true, offsets, sizes,
                           "glBindBuffersRange");
      return;
   case GL_SHADER_STORAGE_BUFFER:
      bind_shader_storage_buffers(ctx, first, count, buffers, true, offsets, sizes,
                                  "glBindBuffersRange");
      return;
   case GL_ATOMIC_COUNTER_BUFFER:
      bind_atomic_buffers(ctx, first, count, buffers, true, offsets, sizes,
                          "glBindBuffersRange");
      return;
   default:
      _mesa_error(ctx, GL_INVALID_ENUM, "glBindBuffersRange(target=%s)",
                  _mesa_enum_to_string(target));
      break;
   }
}

void GLAPIENTRY
_mesa_BindBuffersBase(GLenum target, GLuint first, GLsizei count,
                      const GLuint *buffers)
{
   GET_CURRENT_CONTEXT(ctx);

   if (MESA_VERBOSE & VERBOSE_API) {
      _mesa_debug(ctx, "glBindBuffersBase(%s, %u, %d, %p)\n",
                  _mesa_enum_to_string(target), first, count, buffers);
   }

   switch (target) {
   case GL_TRANSFORM_FEEDBACK_BUFFER:
      bind_xfb_buffers(ctx, first, count, buffers, false, NULL, NULL,
                       "glBindBuffersBase");
      return;
   case GL_UNIFORM_BUFFER:
      bind_uniform_buffers(ctx, first, count, buffers, false, NULL, NULL,
                           "glBindBuffersBase");
      return;
   case GL_SHADER_STORAGE_BUFFER:
      bind_shader_storage_buffers(ctx, first, count, buffers, false, NULL, NULL,
                                  "glBindBuffersBase");
      return;
   case GL_ATOMIC_COUNTER_BUFFER:
      bind_atomic_buffers(ctx, first, count, buffers, false, NULL, NULL,
                          "glBindBuffersBase");
      return;
   default:
      _mesa_error(ctx, GL_INVALID_ENUM, "glBindBuffersBase(target=%s)",
                  _mesa_enum_to_string(target));
      break;
   }
}

static ALWAYS_INLINE void
invalidate_buffer_subdata(struct gl_context *ctx,
                          struct gl_buffer_object *bufObj, GLintptr offset,
                          GLsizeiptr length)
{
   if (ctx->Driver.InvalidateBufferSubData)
      ctx->Driver.InvalidateBufferSubData(ctx, bufObj, offset, length);
}

void GLAPIENTRY
_mesa_InvalidateBufferSubData_no_error(GLuint buffer, GLintptr offset,
                                       GLsizeiptr length)
{
   GET_CURRENT_CONTEXT(ctx);

   struct gl_buffer_object *bufObj = _mesa_lookup_bufferobj(ctx, buffer);
   invalidate_buffer_subdata(ctx, bufObj, offset, length);
}

void GLAPIENTRY
_mesa_InvalidateBufferSubData(GLuint buffer, GLintptr offset,
                              GLsizeiptr length)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;
   const GLintptr end = offset + length;

   /* Section 6.5 (Invalidating Buffer Data) of the OpenGL 4.5 (Compatibility
    * Profile) spec says:
    *
    *     "An INVALID_VALUE error is generated if buffer is zero or is not the
    *     name of an existing buffer object."
    */
   bufObj = _mesa_lookup_bufferobj(ctx, buffer);
   if (!bufObj || bufObj == &DummyBufferObject) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "glInvalidateBufferSubData(name = %u) invalid object",
                  buffer);
      return;
   }

   /* The GL_ARB_invalidate_subdata spec says:
    *
    *     "An INVALID_VALUE error is generated if <offset> or <length> is
    *     negative, or if <offset> + <length> is greater than the value of
    *     BUFFER_SIZE."
    */
   if (offset < 0 || length < 0 || end > bufObj->Size) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "glInvalidateBufferSubData(invalid offset or length)");
      return;
   }

   /* The OpenGL 4.4 (Core Profile) spec says:
    *
    *     "An INVALID_OPERATION error is generated if buffer is currently
    *     mapped by MapBuffer or if the invalidate range intersects the range
    *     currently mapped by MapBufferRange, unless it was mapped
    *     with MAP_PERSISTENT_BIT set in the MapBufferRange access flags."
    */
   if (!(bufObj->Mappings[MAP_USER].AccessFlags & GL_MAP_PERSISTENT_BIT) &&
       bufferobj_range_mapped(bufObj, offset, length)) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "glInvalidateBufferSubData(intersection with mapped "
                  "range)");
      return;
   }

   invalidate_buffer_subdata(ctx, bufObj, offset, length);
}

void GLAPIENTRY
_mesa_InvalidateBufferData_no_error(GLuint buffer)
{
   GET_CURRENT_CONTEXT(ctx);

   struct gl_buffer_object *bufObj =_mesa_lookup_bufferobj(ctx, buffer);
   invalidate_buffer_subdata(ctx, bufObj, 0, bufObj->Size);
}

void GLAPIENTRY
_mesa_InvalidateBufferData(GLuint buffer)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_buffer_object *bufObj;

   /* Section 6.5 (Invalidating Buffer Data) of the OpenGL 4.5 (Compatibility
    * Profile) spec says:
    *
    *     "An INVALID_VALUE error is generated if buffer is zero or is not the
    *     name of an existing buffer object."
    */
   bufObj = _mesa_lookup_bufferobj(ctx, buffer);
   if (!bufObj || bufObj == &DummyBufferObject) {
      _mesa_error(ctx, GL_INVALID_VALUE,
                  "glInvalidateBufferData(name = %u) invalid object",
                  buffer);
      return;
   }

   /* The OpenGL 4.4 (Core Profile) spec says:
    *
    *     "An INVALID_OPERATION error is generated if buffer is currently
    *     mapped by MapBuffer or if the invalidate range intersects the range
    *     currently mapped by MapBufferRange, unless it was mapped
    *     with MAP_PERSISTENT_BIT set in the MapBufferRange access flags."
    */
   if (_mesa_check_disallowed_mapping(bufObj)) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "glInvalidateBufferData(intersection with mapped "
                  "range)");
      return;
   }

   invalidate_buffer_subdata(ctx, bufObj, 0, bufObj->Size);
}

static void
buffer_page_commitment(struct gl_context *ctx,