Add low-level memory management hooks that will be needed to support brk() and sbrk()

8 files changed, 505 insertions, 6 deletions

diff --git a/nuttx/include/nuttx/mm.h b/nuttx/include/nuttx/mm.h
index cfafc8381..53eb95d2b 100644
--- a/nuttx/include/nuttx/mm.h
+++ b/nuttx/include/nuttx/mm.h
@@ -337,6 +337,39 @@ FAR void *mm_zalloc(FAR struct mm_heap_s *heap, size_t size);
 FAR void *mm_memalign(FAR struct mm_heap_s *heap, size_t alignment,
                       size_t size);
 
+/* Functions contained in mm_brkaddr.c **************************************/
+
+FAR void *mm_brkaddr(FAR struct mm_heap_s *heap, int region);
+
+/* Functions contained in umm_brkaddr.c *************************************/
+
+#ifdef CONFIG_MM_USER_HEAP
+FAR void *umm_brkaddr(int region);
+#endif
+
+/* Functions contained in kmm_brkaddr.c *************************************/
+
+#ifdef CONFIG_MM_KERNEL_HEAP
+FAR void *umm_brkaddr(int region);
+#endif
+
+/* Functions contained in mm_extend.c ***************************************/
+
+void mm_extend(FAR struct mm_heap_s *heap, FAR void *mem, size_t size,
+               int region);
+
+/* Functions contained in umm_extend.c **************************************/
+
+#ifdef CONFIG_MM_USER_HEAP
+void umm_extend(FAR void *mem, size_t size, int region);
+#endif
+
+/* Functions contained in kmm_extend.c **************************************/
+
+#ifdef CONFIG_MM_KERNEL_HEAP
+void kmm_extend(FAR void *mem, size_t size, int region);
+#endif
+
 /* Functions contained in mm_mallinfo.c *************************************/
 
 struct mallinfo; /* Forward reference */
diff --git a/nuttx/mm/Makefile b/nuttx/mm/Makefile
index 054393734..f396b3158 100644
--- a/nuttx/mm/Makefile
+++ b/nuttx/mm/Makefile
@@ -53,21 +53,21 @@ endif
 ASRCS  =
 CSRCS  = mm_initialize.c mm_sem.c mm_addfreechunk.c mm_size2ndx.c
 CSRCS += mm_shrinkchunk.c
-CSRCS += mm_calloc.c mm_free.c mm_mallinfo.c mm_malloc.c mm_memalign.c
-CSRCS += mm_realloc.c mm_zalloc.c
+CSRCS += mm_brkaddr.c mm_calloc.c mm_extend.c mm_free.c mm_mallinfo.c
+CSRCS += mm_malloc.c mm_memalign.c mm_realloc.c mm_zalloc.c
 
 # User allocator
 
 CSRCS += umm_initialize.c umm_addregion.c umm_sem.c
-CSRCS += umm_calloc.c umm_free.c umm_mallinfo.c umm_malloc.c
-CSRCS += umm_memalign.c umm_realloc.c umm_zalloc.c
+CSRCS += umm_brkaddr.c umm_calloc.c umm_extend.c umm_free.c umm_mallinfo.c
+CSRCS += umm_malloc.c umm_memalign.c umm_realloc.c umm_zalloc.c
 
 # Kernel allocator
 
 ifeq ($(CONFIG_MM_KERNEL_HEAP),y)
 CSRCS += kmm_initialize.c kmm_addregion.c kmm_sem.c
-CSRCS += kmm_calloc.c kmm_free.c kmm_mallinfo.c kmm_malloc.c
-CSRCS += kmm_memalign.c kmm_realloc.c kmm_zalloc.c
+CSRCS += kmm_brkaddr.c kmm_calloc.c kmm_extend.c kmm_free.c kmm_mallinfo.c
+CSRCS += kmm_malloc.c kmm_memalign.c kmm_realloc.c kmm_zalloc.c
 ifeq ($(CONFIG_DEBUG),y)
 CSRCS += kmm_heapmember.c
 endif
diff --git a/nuttx/mm/kmm_brkaddr.c b/nuttx/mm/kmm_brkaddr.c
new file mode 100644
index 000000000..463744a2a
--- /dev/null
+++ b/nuttx/mm/kmm_brkaddr.c
@@ -0,0 +1,69 @@
+/****************************************************************************
+ * mm/kmm_breakaddr.c
+ *
+ *   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <assert.h>
+
+#include <nuttx/mm.h>
+
+#ifdef CONFIG_MM_KERNEL_HEAP
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: kmm_brkaddr
+ *
+ * Description:
+ *   Return the break address of a region in the user heap
+ *
+ ****************************************************************************/
+
+FAR void *kmm_brkaddr(int region)
+{
+  return mm_brkaddr(&g_kmmheap, region);
+}
+
+#endif /* CONFIG_MM_KERNEL_HEAP */
diff --git a/nuttx/mm/kmm_extend.c b/nuttx/mm/kmm_extend.c
new file mode 100644
index 000000000..1ae1e2865
--- /dev/null
+++ b/nuttx/mm/kmm_extend.c
@@ -0,0 +1,68 @@
+/****************************************************************************
+ * mm/kmm_extend.c
+ *
+ *   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <nuttx/mm.h>
+
+#ifdef CONFIG_MM_KERNEL_HEAP
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: kmm_extend
+ *
+ * Description:
+ *   Extend a region in the kernel heap by add a block of (virtually)
+ *   contiguous memory to the end of the heap.
+ *
+ ****************************************************************************/
+
+void kmm_extend(FAR void *mem, size_t size, int region)
+{
+  mm_extend(&g_kmmheap, mem, size, region);
+}
+
+#endif /* CONFIG_MM_KERNEL_HEAP */
diff --git a/nuttx/mm/mm_brkaddr.c b/nuttx/mm/mm_brkaddr.c
new file mode 100644
index 000000000..a75bcd68b
--- /dev/null
+++ b/nuttx/mm/mm_brkaddr.c
@@ -0,0 +1,69 @@
+/****************************************************************************
+ * mm/mm_brkaddr.c
+ *
+ *   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <assert.h>
+
+#include <nuttx/mm.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: mm_brkaddr
+ *
+ * Description:
+ *   Return the break address of a heap region
+ *
+ ****************************************************************************/
+
+FAR void *mm_brkaddr(FAR struct mm_heap_s *heap, int region)
+{
+  uintptr_t brkaddr;
+  DEBUGASSERT(heap && region < heap->mm_nregions);
+
+  brkaddr = (uintptr_t)heap->mm_heapend[region];
+  return (FAR void *)(brkaddr + SIZEOF_MM_ALLOCNODE);
+}
diff --git a/nuttx/mm/mm_extend.c b/nuttx/mm/mm_extend.c
new file mode 100644
index 000000000..3aa3f37d7
--- /dev/null
+++ b/nuttx/mm/mm_extend.c
@@ -0,0 +1,123 @@
+/****************************************************************************
+ * mm/mm_extend.c
+ *
+ *   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <assert.h>
+
+#include <nuttx/mm.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#define MIN_EXTEND (2 * SIZEOF_MM_ALLOCNODE)
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: mm_extend
+ *
+ * Description:
+ *   Extend a heap region by add a block of (virtually) contiguous memory
+ *   to the end of the heap.
+ *
+ ****************************************************************************/
+
+void mm_extend(FAR struct mm_heap_s *heap, FAR void *mem, size_t size,
+               int region)
+{
+  struct mm_allocnode_s *oldnode;
+  struct mm_allocnode_s *newnode;
+  uintptr_t blockstart;
+  uintptr_t blockend;
+
+  /* Make sure that we were passed valid parameters */
+
+  DEBUGASSERT(heap && mem);
+  DEBUGASSERT(size >= MIN_EXTEND && (unsigned)region < heap->mm_nregions);
+
+  /* Make sure that the memory region are properly aligned */
+
+  blockstart = (uintptr_t)mem;
+  blockend   = blockstart + size;
+
+  DEBUGASSERT(MM_ALIGN_UP(blockstart) == blockstart);
+  DEBUGASSERT(MM_ALIGN_DOWN(blockend) == blockend);
+
+  /* Take the memory manager semaphore */
+
+  mm_takesemaphore(heap);
+
+  /* Get the terminal node in the old heap.  The block to extend must
+   * immediately follow this node.
+   */
+
+  oldnode = heap->mm_heapend[region];
+  DEBUGASSERT((uintptr_t)oldnode + SIZEOF_MM_ALLOCNODE == (uintptr_t)mem);
+
+  /* The size of the old node now extends to the new terminal node.
+   * This is the old size (SIZEOF_MM_ALLOCNODE) plus the size of
+   * the block (size) minus the size of the new terminal node
+   * (SIZEOF_MM_ALLOCNODE) or simply:
+   */
+
+  oldnode->size = size;
+
+  /* The old node should already be marked as allocated */
+
+  DEBUGASSERT((oldnode->preceding & MM_ALLOC_BIT) != 0);
+
+  /* Get and initialize the new terminal node in the heap */
+
+  newnode            = (FAR struct mm_allocnode_s *)(blockend - SIZEOF_MM_ALLOCNODE);
+  newnode->size      = SIZEOF_MM_ALLOCNODE;
+  newnode->preceding = oldnode->size | MM_ALLOC_BIT;
+
+  heap->mm_heapend[region] = newnode;
+  mm_givesemaphore(heap);
+
+  /* Finally "free" the new block of memory where the old terminal node was
+   * located.
+   */
+
+  mm_free(heap, (FAR void *)mem);
+}
diff --git a/nuttx/mm/umm_brkaddr.c b/nuttx/mm/umm_brkaddr.c
new file mode 100644
index 000000000..dc646f20a
--- /dev/null
+++ b/nuttx/mm/umm_brkaddr.c
@@ -0,0 +1,69 @@
+/****************************************************************************
+ * mm/umm_breakaddr.c
+ *
+ *   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <assert.h>
+
+#include <nuttx/mm.h>
+
+#ifdef CONFIG_MM_USER_HEAP
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: umm_brkaddr
+ *
+ * Description:
+ *   Return the break address of a region in the user heap
+ *
+ ****************************************************************************/
+
+FAR void *umm_brkaddr(int region)
+{
+  return mm_brkaddr(&g_mmheap, region);
+}
+
+#endif /* CONFIG_MM_USER_HEAP */
diff --git a/nuttx/mm/umm_extend.c b/nuttx/mm/umm_extend.c
new file mode 100644
index 000000000..6e16e56f8
--- /dev/null
+++ b/nuttx/mm/umm_extend.c
@@ -0,0 +1,68 @@
+/****************************************************************************
+ * mm/umm_extend.c
+ *
+ *   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <nuttx/mm.h>
+
+#ifdef CONFIG_MM_USER_HEAP
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: umm_extend
+ *
+ * Description:
+ *   Extend a region in the user heap by add a block of (virtually)
+ *   contiguous memory to the end of the heap.
+ *
+ ****************************************************************************/
+
+void umm_extend(FAR void *mem, size_t size, int region)
+{
+  mm_extend(&g_mmheap, mem, size, region);
+}
+
+#endif /* CONFIG_MM_USER_HEAP */