sdk/2.1/docs/man/clCreateSubBuffer.xml

<?xml version="1.0" encoding="UTF-8"?>
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              "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd" [
<!ENTITY clCreate_memflagsInc SYSTEM "clCreate_memflagsInc.xml">
]>

<refentry>
    <refentryinfo>
        <keywordset>
            <keyword>clCreateSubBuffer</keyword>
        </keywordset>
    </refentryinfo>

    <refmeta>
        <refentrytitle>
            clCreateSubBuffer
        </refentrytitle>

        <refmiscinfo>
            <copyright>
                <year>2007-2013</year>
                <holder>The Khronos Group Inc.
 Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and/or associated documentation files (the
"Materials"), to deal in the Materials without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Materials, and to
permit persons to whom the Materials are furnished to do so, subject to
the condition that this copyright notice and permission notice shall be included
in all copies or substantial portions of the Materials.</holder>
            </copyright>
        </refmiscinfo>
        <manvolnum>3</manvolnum>
    </refmeta>

<!-- ================================ SYNOPSIS -->

    <refnamediv id="clCreateSubBuffer">
        <refname>
            clCreateSubBuffer
        </refname>

        <refpurpose>
            Creates a new buffer object (referred to as a sub-buffer object) from an existing buffer object.
        </refpurpose>
    </refnamediv>

    <refsynopsisdiv xmlns:xlink="http://www.w3.org/1999/xlink"><title></title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>
                    <link xlink:href="abstractDataTypes.html">cl_mem</link> <function>clCreateSubBuffer</function>
                </funcdef>

                <paramdef><link xlink:href="abstractDataTypes.html">cl_mem</link><parameter>buffer</parameter></paramdef>
                <paramdef><link xlink:href="enums.html#cl_mem_flags">cl_mem_flags</link><parameter>flags</parameter></paramdef>
                <paramdef><link xlink:href="enums.html#cl_buffer_create_type">cl_buffer_create_type</link><parameter>buffer_create_type</parameter></paramdef>
                <paramdef>const <link xlink:href="scalarDataTypes.html">void</link><parameter>*buffer_create_info</parameter></paramdef>
                <paramdef><link xlink:href="scalarDataTypes.html">cl_int</link><parameter>*errcode_ret</parameter></paramdef>

            </funcprototype>
        </funcsynopsis>
    </refsynopsisdiv>

<!-- ================================ PARAMETERS -->

    <refsect1 id="parameters">
        <title>Parameters</title>
        <variablelist>
            <varlistentry>
                <term><varname>buffer</varname></term>
                <listitem>
                    <para>A valid buffer object and cannot be a sub-buffer object.</para>
               </listitem>
            </varlistentry>

            <varlistentry>
                <term>
                    <varname>flags</varname>
                </term>
                <listitem>
                    <para>
                      A bit-field that is used to specify allocation and
                      usage information about the sub-buffer memory object
                      being created and is described in the table below.  If the
                      <constant>CL_MEM_READ_WRITE</constant>, <constant>CL_MEM_READ_ONLY</constant>
                      or <constant>CL_MEM_WRITE_ONLY</constant> values are not
                      specified in <varname>flags</varname>, they are inherited
                      from the corresponding memory access qualifers associated with
                      <varname>buffer</varname>. The <constant>CL_MEM_USE_HOST_PTR</constant>,
                      <constant>CL_MEM_ALLOC_HOST_PTR</constant> and
                      <constant>CL_MEM_COPY_HOST_PTR</constant> values cannot
                      be specified in <varname>flags</varname> but are inherited
                      from the corresponding memory access qualifiers associated with
                      <varname>buffer</varname>.  If <constant>CL_MEM_COPY_HOST_PTR</constant>
                      is specified in  the memory access qualifier values associated with
                      <varname>buffer</varname> it does not imply any additional copies
                      when the sub-buffer is created from <varname>buffer</varname>.
                      If the <constant>CL_MEM_HOST_WRITE_ONLY</constant>,
                      <constant>CL_MEM_HOST_READ_ONLY</constant> or
                      <constant>CL_MEM_HOST_NO_ACCESS</constant> values are not specified in
                      <varname>flags</varname>, they are inherited from the corresponding memory
                      access qualifiers associated with <varname>buffer</varname>.
                    </para>

                    <!-- Table 5.3 -->
                    &clCreate_memflagsInc;

                </listitem>
            </varlistentry>
            <!-- END PARAMETER TABLE  -->

            <varlistentry>
              <term><varname>buffer_create_type</varname> and <varname>buffer_create_info</varname></term>

              <listitem>
                <para>
                  Describes the type of buffer object to be created. The list of supported values
                  for <varname>buffer_create_type</varname> and corresponding descriptor that
                  <varname>buffer_create_info</varname> points to is described below.
                </para>

                <!-- table 5.4 -->
                <informaltable frame="all">
                  <tgroup cols="2" align="left" colsep="1" rowsep="1">
                    <colspec colname="col1" colnum="1" />
                    <colspec colname="col2" colnum="2" />
                    <thead>
                      <row>
                        <entry>cl_buffer_create_type</entry>
                        <entry>Description</entry>
                      </row>
                    </thead>

                    <tbody>
                      <row>
                        <entry><constant>CL_BUFFER_CREATE_TYPE_REGION</constant></entry>
                        <entry>
                          <para>
                            Create a buffer object that represents a specific region in
                            <varname>buffer</varname>.
                          </para>

                          <para>
                            <varname>buffer_create_info</varname> is a pointer to the following
                            structure:
                          </para>

                          <literallayout>
typedef struct _cl_buffer_region {
    size_t origin;
    size_t size;
} cl_buffer_region;
                          </literallayout>

                          <para>
                            (<varname>origin, size</varname>) defines the offset and size in
                            bytes in <varname>buffer</varname>.
                          </para>

                          <para>
                            If <varname>buffer</varname> is created with
                            <constant>CL_MEM_USE_HOST_PTR</constant>, the <varname>host_ptr</varname>
                            associated with the buffer object returned is <varname>host_ptr</varname>
                            + <varname>origin</varname>.
                          </para>

                          <para>
                            The buffer object returned references the data store allocated for
                            <varname>buffer</varname> and points to a specific region given by
                            (<varname>origin, size</varname>) in this data store.
                          </para>

                          <para>
                            <constant>CL_INVALID_VALUE</constant> is returned in
                            <varname>errcode_ret</varname> if the region specified by
                            (<varname>origin, size</varname>) is out of bounds in
                            <varname>buffer</varname>.
                          </para>

                          <para>
                            <constant>CL_INVALID_BUFFER_SIZE</constant> if <varname>size</varname>
                            is 0.
                          </para>

                          <para>
                            <constant>CL_MISALIGNED_SUB_BUFFER_OFFSET</constant> is
                            returned in <varname>errcode_ret</varname> if there are no
                            devices in context associated with <varname>buffer</varname>
                            for which the <varname>origin</varname> value is aligned to the
                            <constant>CL_DEVICE_MEM_BASE_ADDR_ALIGN</constant> value.
                          </para>
                        </entry>
                      </row>
                    </tbody>
                  </tgroup>
                </informaltable>
              </listitem>
            </varlistentry>
        </variablelist>
    </refsect1>

<!-- ================================ NOTES  -->

  <refsect1 id="notes"><title>Notes</title>
        <para>
          Concurrent reading from, writing to and copying between both a buffer object and
          its sub-buffer object(s) is undefined.  Concurrent reading from, writing to and
          copying between overlapping sub-buffer objects created with the same buffer object
          is undefined.  Only reading from both a buffer object and its sub-buffer objects or
          reading from multiple overlapping sub-buffer objects is defined.
        </para>
    </refsect1>

<!-- ================================ ERRORS  -->

    <refsect1 id="errors"><title>Errors</title>
        <para>
          Returns <errorname>CL_SUCCESS</errorname> if the function is executed 
          successfully. Otherwise, it 
          returns one of the following errors in <varname>errcode_ret</varname>
        </para>

        <itemizedlist mark="disc">
            <listitem>
              <errorname>CL_INVALID_MEM_OBJECT</errorname> if <varname>buffer</varname> is not
              a valid buffer object or is a sub-buffer object.
            </listitem>

            <listitem>
              <errorname>CL_INVALID_VALUE</errorname> if <varname>buffer</varname> was created
              with <constant>CL_MEM_WRITE_ONLY</constant> and <varname>flags</varname> specifies
              <constant>CL_MEM_READ_WRITE</constant> or <constant>CL_MEM_READ_ONLY</constant>, or
              if <varname>buffer</varname> was created with <constant>CL_MEM_READ_ONLY</constant>
              and <varname>flags</varname> specifies <constant>CL_MEM_READ_WRITE</constant>
              or <constant>CL_MEM_WRITE_ONLY</constant>, or if <varname>flags</varname>
              specifies <constant>CL_MEM_USE_HOST_PTR</constant>
              or <constant>CL_MEM_ALLOC_HOST_PTR</constant> or
              <constant>CL_MEM_COPY_HOST_PTR</constant>.
            </listitem>

            <listitem>
              <errorname>CL_INVALID_VALUE</errorname> if <varname>buffer</varname> was created with
              <constant>CL_MEM_HOST_WRITE_ONLY</constant> and <varname>flags</varname> specifies
              <constant>CL_MEM_HOST_READ_ONLY</constant> or if <varname>buffer</varname>
              was created with <constant>CL_MEM_HOST_READ_ONLY</constant> and
              <varname>flags</varname> specifies <constant>CL_MEM_HOST_WRITE_ONLY</constant>, or if
              <varname>buffer</varname> was created with <constant>CL_MEM_HOST_NO_ACCESS</constant>
              and <varname>flags</varname> specifies <constant>CL_MEM_HOST_READ_ONLY</constant>
              or <constant>CL_MEM_HOST_WRITE_ONLY</constant>.
            </listitem>

            <listitem>
              <errorname>CL_INVALID_VALUE</errorname> if value specified in
              <varname>buffer_create_type</varname> is not valid.
            </listitem>

            <listitem>
              <errorname>CL_INVALID_VALUE</errorname> if value(s) specified
              in <varname>buffer_create_info</varname> (for a given
              <varname>buffer_create_type</varname>) is not valid or if
              <varname>buffer_create_info</varname> is NULL.
            </listitem>

            <listitem>
                <errorname>CL_INVALID_BUFFER_SIZE</errorname> if size is 0.
            </listitem>

            <listitem>
              <errorname>CL_MEM_OBJECT_ALLOCATION_FAILURE</errorname> if there is a failure to
              allocate memory for sub-buffer object.
            </listitem>

            <listitem>
              <errorname>CL_OUT_OF_RESOURCES</errorname> if there is a failure to allocate
              resources required by the OpenCL implementation on the device.
            </listitem>

            <listitem>
              <errorname>CL_OUT_OF_HOST_MEMORY</errorname> if there is a failure to allocate
              resources required by the OpenCL implementation on the host.
            </listitem>
        </itemizedlist>
    </refsect1>

<!-- ================================ EXAMPLE  -->
<!-- DO NOT DELETE IN CASE AN EXAMPLE IS ADDED IN THE FUTURE -->
<!--
    <refsect2 id="example1">
        <title>
            Example
        </title>

        <informaltable frame="none">
            <tgroup cols="1" align="left" colsep="0" rowsep="0">
                <colspec colname="col1" colnum="1" />
                <tbody>
                    <row>
                        <entry>
                            Example goes here - it will be set in "code" type with white space preserved.
                        </entry>
                    </row>
                </tbody>
            </tgroup>
        </informaltable>
    </refsect2>
-->

<!-- ================================ SPECIFICATION  -->
<!-- Set the "uri" attribute in the <olink /> element to the "named destination" for the PDF page
-->
    <refsect1 id="specification"><title>Specification</title>
        <para>
            <imageobject>
                <imagedata fileref="pdficon_small1.gif" format="gif" />
            </imageobject>

            <olink uri="clCreateSubBuffer">OpenCL Specification</olink>
        </para>
    </refsect1>

<!-- ================================ ALSO SEE  -->

    <refsect1 id="seealso"><title>Also see</title>
        <para>
            <citerefentry><refentrytitle>clCreateBuffer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>clEnqueueReadBuffer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>clEnqueueWriteBuffer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>clEnqueueCopyBuffer</refentrytitle></citerefentry>
        </para>
    </refsect1>

<!-- ================================ COPYRIGHT  -->
<!-- Content included from copyright.inc.xsl -->

    <refsect3 id="Copyright"><title></title>
        <imageobject>
                <imagedata fileref="KhronosLogo.jpg" format="jpg" />
        </imageobject>
        <para />
    </refsect3>

<!-- 6-Dec-2013, rev. 19 -->
</refentry>