heap: Add _Heap_Greedy_allocate_all_except_largest

Add rtems_workspace_greedy_allocate_all_except_largest() and
rtems_heap_greedy_allocate_all_except_largest().

2 files changed, 32 insertions, 2 deletions

diff --git a/cpukit/rtems/include/rtems/rtems/support.h b/cpukit/rtems/include/rtems/rtems/support.h
index 1f3cd3da76..335b8c02fa 100644
--- a/cpukit/rtems/include/rtems/rtems/support.h
+++ b/cpukit/rtems/include/rtems/rtems/support.h
@@ -99,7 +99,7 @@ bool rtems_workspace_free(
 /**
  * @brief Greedy allocate that empties the workspace.
  *
- * Afterward the heap has at most @a block_count allocateable blocks of sizes
+ * Afterwards the heap has at most @a block_count allocatable blocks of sizes
  * specified by @a block_sizes.  The @a block_sizes must point to an array with
  * @a block_count members.  All other blocks are used.
  *
@@ -111,10 +111,24 @@ void *rtems_workspace_greedy_allocate(
 );
 
 /**
+ * @brief Greedy allocate all blocks except the largest free block.
+ *
+ * Afterwards the heap has at most one allocatable block.  This block is the
+ * largest free block if it exists.  The allocatable size of this block is
+ * stored in @a allocatable_size.  All other blocks are used.
+ *
+ * @see rtems_workspace_greedy_free().
+ */
+void *rtems_workspace_greedy_allocate_all_except_largest(
+  uintptr_t *allocatable_size
+);
+
+/**
  * @brief Frees space of a greedy allocation.
  *
  * The @a opaque argument must be the return value of
- * rtems_workspace_greedy_allocate().
+ * rtems_workspace_greedy_allocate() or
+ * rtems_workspace_greedy_allocate_all_except_largest().
  */
 void rtems_workspace_greedy_free( void *opaque );
 
diff --git a/cpukit/rtems/src/workspacegreedy.c b/cpukit/rtems/src/workspacegreedy.c
index 8e43370336..4f46e7d919 100644
--- a/cpukit/rtems/src/workspacegreedy.c
+++ b/cpukit/rtems/src/workspacegreedy.c
@@ -40,6 +40,22 @@ void *rtems_workspace_greedy_allocate(
   return opaque;
 }
 
+void *rtems_workspace_greedy_allocate_all_except_largest(
+  uintptr_t *allocatable_size
+)
+{
+  void *opaque;
+
+  _Thread_Disable_dispatch();
+  opaque = _Heap_Greedy_allocate_all_except_largest(
+    &_Workspace_Area,
+    allocatable_size
+  );
+  _Thread_Enable_dispatch();
+
+  return opaque;
+}
+
 void rtems_workspace_greedy_free( void *opaque )
 {
   _Thread_Disable_dispatch();