Changeset 639

Timestamp:

Jul 20, 2015, 6:02:55 PM (9 years ago)

Author:

guerin

Message:

fat32: add Fat-Cache levels on demand

File:

• soft/giet_vm/giet_fat32/fat32.c (modified) (4 diffs)

soft/giet_vm/giet_fat32/fat32.c

@@ -420 +420 @@
 
 //////////////////////////////////////////////////////////////////////////////////
+// The following function allocates and initializes a new Fat-Cache node.
+// Its first child can be specified (used when adding a cache level).
+// The Fat-Cache is initialized as empty: all children set to NULL.
+// It returns a pointer to a new Fat-Cache node.
+//////////////////////////////////////////////////////////////////////////////////
+
+static fat_cache_node_t* _allocate_one_cache_node( fat_cache_node_t* first_child );
+
+//////////////////////////////////////////////////////////////////////////////////
 // The following function allocates and initializes a new inode, 
 // using the values defined by the arguments.
 // If the "cache_allocate" argument is true ans empty cache is allocated.
-// The Fat-Cache is initialised as empty: all children set to NULL.
 // It returns a pointer on the new inode.
 //////////////////////////////////////////////////////////////////////////////////
@@ -874 +882 @@
 
 
+////////////////////////////////////////////////////////////
+static fat_cache_node_t* _allocate_one_cache_node( fat_cache_node_t* first_child )
+{
+    fat_cache_node_t* cnode;
+    unsigned int i;
+
+    cnode = _malloc( sizeof(fat_cache_node_t) );
+
+    cnode->children[0] = first_child;
+    for ( i = 1 ; i < 64 ; i++ )
+        cnode->children[i] = NULL;
+
+    return cnode;
+}   // end _allocate_one_cache_node()
+
+
 
 ////////////////////////////////////////////////////////////
@@ -901 +925 @@
     if ( cache_allocate )
     {
-        fat_cache_node_t* new_cache  = _malloc( sizeof(fat_cache_node_t) );
-
-        new_inode->cache    = new_cache;
+        new_inode->cache    = _allocate_one_cache_node( NULL );
         new_inode->levels   = _get_levels_from_size( size );
-        
-        unsigned int index;
-        for ( index = 0 ; index < 64 ; index ++ )  new_cache->children[index] = NULL;
     }
 
@@ -1194 +1213 @@
                                   unsigned int  cluster )
 {
+    // add cache levels if needed
+    while ( _get_levels_from_size( (cluster_id + 1) * 4096 ) > inode->levels )
+    {
+#if (GIET_DEBUG_FAT & 1)
+if ( _get_proctime() > GIET_DEBUG_FAT )
+_printf("\n[DEBUG FAT] _allocate_one_buffer() : adding a cache level\n" );
+#endif
+
+        inode->cache = _allocate_one_cache_node( inode->cache );
+        inode->levels++;
+    }
+
     // search the 64-tree cache from top to bottom 
     fat_cache_node_t*  node   = inode->cache;