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| <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN" |
| "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd" [ |
| <!ENTITY map_flags_Inc SYSTEM "map_flags_Inc.xml"> |
| <!ENTITY accessMappedInc SYSTEM "accessMappedInc.xml"> |
| ]> |
| |
| <refentry> |
| <refentryinfo> |
| <keywordset> |
| <keyword>clEnqueueMapBuffer</keyword> |
| </keywordset> |
| </refentryinfo> |
| |
| <refmeta> |
| <refentrytitle> |
| clEnqueueMapBuffer |
| </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="clEnqueueMapBuffer"> |
| <refname> |
| clEnqueueMapBuffer |
| </refname> |
| |
| <refpurpose> |
| Enqueues a command to map a region of the buffer object given by <varname>buffer</varname> |
| into the host address space and returns a pointer to this mapped region. |
| </refpurpose> |
| </refnamediv> |
| |
| <refsynopsisdiv xmlns:xlink="http://www.w3.org/1999/xlink"><title></title> |
| <funcsynopsis> |
| <funcprototype> |
| <funcdef> |
| <link xlink:href="scalarDataTypes.html">void</link> * <function>clEnqueueMapBuffer</function> |
| </funcdef> |
| <paramdef><link xlink:href="abstractDataTypes.html">cl_command_queue</link><parameter>command_queue</parameter></paramdef> |
| <paramdef><link xlink:href="abstractDataTypes.html">cl_mem</link><parameter>buffer</parameter></paramdef> |
| <paramdef><link xlink:href="enums.html#cl_bool">cl_bool</link><parameter>blocking_map</parameter></paramdef> |
| <paramdef><link xlink:href="enums.html#cl_map_flags">cl_map_flags</link><parameter>map_flags</parameter></paramdef> |
| <paramdef><link xlink:href="scalarDataTypes.html">size_t</link><parameter>offset</parameter></paramdef> |
| <paramdef><link xlink:href="scalarDataTypes.html">size_t</link><parameter>size</parameter></paramdef> |
| <paramdef><link xlink:href="scalarDataTypes.html">cl_uint</link><parameter>num_events_in_wait_list</parameter></paramdef> |
| <paramdef>const <link xlink:href="abstractDataTypes.html">cl_event</link><parameter>*event_wait_list</parameter></paramdef> |
| <paramdef><link xlink:href="abstractDataTypes.html">cl_event</link><parameter>*event</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> command_queue </varname> </term> |
| <listitem> |
| <para> |
| Must be a valid host command-queue. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term> <varname> blocking_map </varname> </term> |
| <listitem> |
| <para> |
| Indicates if the map operation is <varname>blocking</varname> or |
| <varname>non-blocking</varname>. |
| </para> |
| |
| <para> |
| If <varname>blocking_map</varname> is <constant>CL_TRUE</constant>, |
| <function>clEnqueueMapBuffer</function> does not return until the specified |
| region in <varname>buffer</varname> is mapped into the host address space |
| and the application can access the contents of the mapped region using |
| the pointer returned by <function>clEnqueueMapBuffer</function>. |
| </para> |
| |
| <para> |
| If <varname>blocking_map</varname> is <constant>CL_FALSE</constant> |
| i.e. map operation is non-blocking, the pointer to the mapped region |
| returned by <function>clEnqueueMapBuffer</function> cannot be used until |
| the map command has completed. The <varname>event</varname> argument |
| returns an event object which can be used to query the execution status |
| of the map command. When the map command is completed, the application |
| can access the contents of the mapped region using the pointer returned |
| by <function>clEnqueueMapBuffer</function>. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <!-- ================================ PARAMETER TABLE (OPTIONAL) --> |
| |
| <varlistentry> |
| <term><varname>map_flags</varname></term> |
| <listitem> |
| <para> |
| A bit-bield with the following supported values. |
| </para> |
| |
| &map_flags_Inc; |
| |
| </listitem> |
| </varlistentry> |
| |
| <!-- ================================ END PARAMETER TABLE --> |
| |
| <varlistentry> |
| <term> <varname> buffer </varname> </term> |
| <listitem> |
| <para> |
| A valid buffer object. The OpenCL context associated |
| with <varname>command_queue</varname> |
| and <varname>buffer</varname> must be the same. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term> |
| <varname> |
| offset, |
| </varname> |
| <varname> |
| size |
| </varname> |
| </term> |
| |
| <listitem> |
| <para> |
| The offset in bytes and the size of the region in the buffer object that is being mapped. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term> |
| <varname> |
| event_wait_list, |
| </varname> |
| <varname> |
| num_events_in_wait_list |
| </varname> |
| </term> |
| |
| <listitem> |
| <para> |
| Specify events that need to complete before this particular |
| command can be executed. If <varname>event_wait_list</varname> |
| is NULL, then this particular command does not wait on any |
| event to complete. If <varname>event_wait_list</varname> is |
| NULL, <varname>num_events_in_wait_list</varname> must be 0. If |
| <varname>event_wait_list</varname> is not NULL, the list of events |
| pointed to by <varname>event_wait_list</varname> must be valid |
| and <varname>num_events_in_wait_list</varname> must be greater |
| than 0. The events specified in <varname>event_wait_list</varname> |
| act as synchronization points. The context associated with events in |
| <varname>event_wait_list</varname> and <varname>command_queue</varname> must |
| be the same. The memory associated with <varname>event_wait_list</varname> |
| can be reused or freed after the function returns. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term> <varname> event </varname> </term> |
| <listitem> |
| <para> |
| Returns an event object that identifies this particular copy command |
| and can be used to query or queue a wait for this particular command |
| to complete. <varname>event</varname> can be NULL in which case |
| it will not be possible for the application to query the status of |
| this command or queue a wait for this command to complete. If the |
| <varname>event_wait_list</varname> and the <varname>event</varname> |
| arguments are not NULL, the <varname>event</varname> argument should not |
| refer to an element of the <varname>event_wait_list</varname> array. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term> <varname> errcode_ret </varname> </term> |
| <listitem> |
| <para> |
| Returns an appropriate error code. If <varname>errcode_ret</varname> |
| is NULL, no error code is returned. |
| </para> |
| </listitem> |
| </varlistentry> |
| </variablelist> |
| </refsect1> |
| |
| <!-- ================================ NOTES --> |
| |
| <refsect1 id="notes"><title>Notes</title> |
| <para> |
| The returned pointer maps a region starting at <varname>offset</varname> and is at |
| least <varname>size</varname> bytes in size. The result of a memory access outside |
| this region is undefined. |
| </para> |
| |
| <para> |
| If the buffer object is created with <constant>CL_MEM_USE_HOST_PTR</constant> set in |
| <varname>mem_flags</varname>, the following will be true: |
| </para> |
| |
| <itemizedlist mark="disc"> |
| <listitem> |
| The <varname>host_ptr</varname> specified in |
| <citerefentry><refentrytitle>clCreateBuffer</refentrytitle></citerefentry> |
| is guaranteed to contain the latest bits in the region being mapped when the |
| <function>clEnqueueMapBuffer</function> command has completed. |
| </listitem> |
| |
| <listitem> |
| The pointer value returned by <function>clEnqueueMapBuffer</function> will be derived |
| from the <varname>host_ptr</varname> specified when the buffer object is created. |
| </listitem> |
| </itemizedlist> |
| |
| <para> |
| Mapped buffer objects are unmapped using |
| <citerefentry><refentrytitle>clEnqueueUnmapMemObject</refentrytitle></citerefentry>. |
| </para> |
| |
| <para> |
| <function>clEnqueueMapBuffer</function> |
| and <citerefentry><refentrytitle>clEnqueueMapImage</refentrytitle></citerefentry> |
| increment the mapped count of the memory object. The initial mapped count value of a |
| memory object is zero. Multiple calls to <function>clEnqueueMapBuffer</function> or |
| <citerefentry><refentrytitle>clEnqueueMapImage</refentrytitle></citerefentry> on the |
| same memory object will increment this mapped count by appropriate number of calls. |
| <citerefentry><refentrytitle>clEnqueueUnmapMemObject</refentrytitle></citerefentry> |
| decrements the mapped count of the memory object. |
| </para> |
| |
| <para> |
| <function>clEnqueueMapBuffer</function> |
| and <citerefentry><refentrytitle>clEnqueueMapImage</refentrytitle></citerefentry> |
| act as synchronization points for a region of the buffer object being mapped. |
| </para> |
| |
| &accessMappedInc; |
| |
| </refsect1> |
| |
| <!-- ================================ ERRORS --> |
| |
| <refsect1 id="errors"><title>Errors</title> |
| <para> |
| <function>clEnqueueMapBuffer</function> will return a pointer to the mapped region. |
| The <varname>errcode_ret</varname> is set |
| to <errorname>CL_SUCCESS</errorname>. |
| </para> |
| |
| <para> |
| A NULL pointer is returned otherwise with one of the following error values returned |
| in <varname>errcode_ret</varname>: |
| </para> |
| |
| <itemizedlist mark="disc"> |
| <listitem> |
| <errorname>CL_INVALID_COMMAND_QUEUE</errorname> if <varname>command_queue</varname> |
| is not a valid host command-queue. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_INVALID_CONTEXT</errorname> if the context associated with |
| <varname>command_queue</varname> and <varname>buffer</varname> |
| are not the same or if the context associated with <varname>command_queue</varname> |
| and events in <varname>event_wait_list</varname> are not the same. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_INVALID_MEM_OBJECT</errorname> if |
| <varname>buffer</varname> is not a valid image object. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_INVALID_VALUE</errorname> if region being mapped given by |
| (<varname>offset</varname>, <varname>size</varname>) |
| is out of bounds or if <varname>size</varname> is 0 or values specified in |
| <varname>map_flags</varname> are not valid. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_INVALID_EVENT_WAIT_LIST</errorname> |
| if <varname>event_wait_list</varname> is NULL and |
| <varname>num_events_in_wait_list</varname> > 0, |
| or <varname>event_wait_list</varname> is not NULL and |
| <varname>num_events_in_wait_list</varname> is 0, or if event objects in |
| <varname>event_wait_list</varname> are not valid events. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_MISALIGNED_SUB_BUFFER_OFFSET</errorname> if |
| <varname>buffer</varname> is a sub-buffer object and <varname>offset</varname> |
| specified when the sub-buffer object is created is not aligned to |
| <constant>CL_DEVICE_MEM_BASE_ADDR_ALIGN</constant> value for device associated |
| with <varname>queue</varname>. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_MAP_FAILURE</errorname> if there is a failure to map the |
| requested region into the host address space. This error cannot occur for |
| buffer objects created with <constant>CL_MEM_USE_HOST_PTR</constant> or |
| <constant>CL_MEM_ALLOC_HOST_PTR</constant>. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_EXEC_STATUS_ERROR_FOR_EVENTS_IN_WAIT_LIST</errorname> if the |
| map operation is blocking and the execution status of any of the events in |
| <varname>event_wait_list</varname> is a negative integer value. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_MEM_OBJECT_ALLOCATION_FAILURE</errorname> if there is a failure to |
| allocate memory for data store associated with <varname>buffer</varname>. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_INVALID_OPERATION</errorname> if <varname>buffer</varname> |
| has been created with <constant>CL_MEM_HOST_WRITE_ONLY</constant> or |
| <constant>CL_MEM_HOST_NO_ACCESS</constant> and <constant>CL_MAP_READ</constant> |
| is set in <varname>map_flags</varname> or if <varname>buffer</varname> |
| has been created with <constant>CL_MEM_HOST_READ_ONL</constant> or |
| <constant>CL_MEM_HOST_NO_ACCESS</constant> and <constant>CL_MAP_WRITE</constant> |
| or <constant>CL_MAP_WRITE_INVALIDATE_REGION</constant> is set in |
| <varname>map_flags</varname>. |
| </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 mapping would lead to |
| overlapping regions being mapped for writing. |
| </listitem> |
| |
| <listitem> |
| <errorname>CL_INVALID_OPERATION</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="clEnqueueMapBuffer">OpenCL Specification</olink> |
| </para> |
| </refsect1> |
| |
| <!-- ================================ ALSO SEE --> |
| |
| <refsect1 id="seealso"><title>Also see</title> |
| <para> |
| <citerefentry><refentrytitle>clEnqueueMapImage</refentrytitle></citerefentry>, |
| <citerefentry><refentrytitle>clEnqueueUnmapMemObject</refentrytitle></citerefentry>, |
| <citerefentry><refentrytitle>clEnqueueSVMMap</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> |
| |
| <!-- 24-Oct-2015, API rev. 19 --> |
| </refentry> |
| |
