kalloc and kfree interface and abstraction

[cortex-from-scratch] / lib / pool.c

diff --git a/lib/pool.c b/lib/pool.c
index 83b2df2..b3f1828 100644 (file)
--- a/lib/pool.c
+++ b/lib/pool.c
@@ -12,15 +12,21 @@
  * to protect certain zones.
  *
  * This work is based on an article of Ben Kenwright.
+ *
+ * Blocks are fixed size. In some situations ideal, in some situation
+ * may be not. It's fast.
  * 
  * Preconditions: programmer should make sure the SRAM entry point
  * + (blocks * blocksize) is free. 
  *
  * $SAMPLE USAGE$
- * KERNEL: can initialize a big pool for all user tasks
+ * KERNEL: initialize one (or multiple!) fixed memory-sized 
+ * kernal heaps
  *
  * USER TASKS/PROCESS: can use this to dynamically allocate their
- * own memory (i.e. heap)
+ * own memory (i.e. heap). You might argue that a fixed size memory
+ * pool is not ideal, but you would be amazed that many programs
+ * use structs of more or less similar size.
  * 
  * 
  * * */
@@ -34,7 +40,7 @@
 #include <lib/string.h>
 
  
-void kpool_init(mem_pool_t * pool, size_t size_arg, unsigned int blocks_arg, unsigned char* entry_SRAM) {
+void pool_init(mem_pool_t * pool, size_t size_arg, unsigned int blocks_arg, unsigned char* entry_SRAM) {
 
         pool->blocks = blocks_arg;
         pool->block_size = size_arg;
@@ -61,7 +67,8 @@ unsigned int IndexFromAddr(mem_pool_t * pool, const unsigned char* p) {
 }
 
 /* alloc and free */ 
-void * kalloc(mem_pool_t * pool) {
+void * alloc(void * s) {
+       mem_pool_t * pool = (mem_pool_t *) s;
        if (pool->blocks_init < pool->blocks ) {
                 unsigned int * p = (unsigned int *)AddrFromIndex(pool, pool->blocks_init );
                *p = pool->blocks_init + 1;
@@ -83,23 +90,26 @@ void * kalloc(mem_pool_t * pool) {
         return ret;
  }
 
-void kfree(mem_pool_t * pool, void* p)  {
-        if (pool->m_next != NULL) {
-                (*(unsigned int *)p) = IndexFromAddr(pool, pool->m_next );
-                pool->m_next = (unsigned char*)p;
-       }
-        else {
+void free(void * s, void* p)  {
+
+       mem_pool_t * pool = (mem_pool_t *) s;
+       if (pool->m_next != NULL) {
+               (*(unsigned int *)p) = IndexFromAddr(pool, pool->m_next );
+               pool->m_next = (unsigned char*)p;
+       }
+       else {
                 *((unsigned int*)p) = pool->blocks;
                 pool->m_next = (unsigned char*) p;
-        }
+       }
                
-        ++pool->free_blocks;
+       ++pool->free_blocks;
 }
 
 /* Heap info helper functions */
 
-void kheap_info(mem_pool_t * pool) {
+void heap_info(void * s) {
 
+       mem_pool_t * pool = (mem_pool_t *) s;
 
        printf("HEAP INFO:\n");
        printf("BLOCKS FREE: %d\n", pool->free_blocks);