cleaning up in progress

4 files changed, 47 insertions, 65 deletions

diff --git a/asm/NOTES b/asm/NOTES
deleted file mode 100644
index d5df67a..0000000
--- a/asm/NOTES
+++ /dev/null
@@ -1,2 +0,0 @@
-files in this directory should not depend on any other files.
-This is not supported by the build-system by now.
diff --git a/kernel/kmalloc.c b/kernel/kmalloc.c
index d235f55..e3b0863 100644
--- a/kernel/kmalloc.c
+++ b/kernel/kmalloc.c
@@ -1,36 +1,43 @@
 #define FOOLOS_MODULE_NAME "kmalloc"
 #include "kmalloc.h"
-#include <stddef.h>
+
 #include "lib/logger/log.h"
 
-#define MEM_SIZE    1024*1024*8
+// 8MB for in kernel-memory
+#define MEM_SIZE  1024*1024*8
+
+static uint8_t    data[MEM_SIZE]; // bytes
 
-static uint8_t	    data[MEM_SIZE]; //8MB kernel memory managed by kmalloc
-static uint32_t	    next;
-static uint32_t	    first;
-static uint8_t	    init=0;
+static uint32_t   next;
+static uint32_t   first;
+static uint8_t    init=0;
 
-void kmallocinit()
+// will be initialized on first call to kballoc() //
+static void kmallocinit()
 {
     next=&(data[0]);
     first=next;
 
-    if(next%4096) //align (TODO: check how to tell gcc to do that)
+    //TODO: optionally tell gcc to align this itself.
+    if(next%4096) 
     {
-	next+=4096; 
-	next/=4096;
-	next*=4096;
+        next+=4096; 
+        next/=4096;
+        next*=4096;
     }
+    //
 
-//    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"kmalloc_init: 0x%08X",next);
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"kmalloc_init: 0x%08X",next);
     init=1;
 }
 
-// kernel block memory allocation
+// kernel block memory allocation //
 uint32_t kballoc(uint32_t size)
 {
     size*=4096;
+
     if(!init)kmallocinit();
+
     uint32_t old=next;
     next+=size;
 
@@ -38,14 +45,14 @@ uint32_t kballoc(uint32_t size)
     {
         panic(FOOLOS_MODULE_NAME,"kballoc ran out of memory! maybe increase MEM_SIZE in kmalloc.c?");
     }
- //   log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"(%d) : 0x%08X (~%dKB left)",size,old,(MEM_SIZE-next+first)/1024);
-    
+
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"(%d) : 0x%08X (~%dKB left)",size,old,(MEM_SIZE-next+first)/1024);
     return old;
 }
 
-//TODO!
+//TODO: allow freeing memory!!
 uint32_t kbfree(uint32_t pos)
 {
-
+        panic(FOOLOS_MODULE_NAME,"kbfree NOT IMPLEMENTED YET");
 }
 
diff --git a/kernel/kmalloc.h b/kernel/kmalloc.h
index 2f89f8a..2faecb8 100644
--- a/kernel/kmalloc.h
+++ b/kernel/kmalloc.h
@@ -1,2 +1,16 @@
 #include <stdint.h>
-uint32_t kballoc(uint32_t size);
+
+/* 
+ * Kernel Block Memory Allocation
+ *
+ * The kernel reserves some memory for internal operation, since  malloc 
+ * is not available.
+ *
+ * Last Revision: 17 AUG 2018
+ */
+
+// Allocate size*4096 bytes and returns a 32-bit pointer
+uint32_t kballoc  (uint32_t size);
+
+// Free memory allocated before by supplying the address (TODO)
+uint32_t kbfree   (uint32_t addr);
diff --git a/kernel/usermode.c b/kernel/usermode.c
index eb19cdf..db4ac9f 100644
--- a/kernel/usermode.c
+++ b/kernel/usermode.c
@@ -1,64 +1,27 @@
-#include "usermode.h"
 #define FOOLOS_MODULE_NAME "usermode"
-#include "lib/logger/log.h"
-#include "syscalls.h"
-#include <stddef.h>
-
-tss_struct sys_tss; //Define the TSS as a global structure
-
-// generic syscall interface!
-/*
-int syscall(int call, int p1, int p2, int p3)
-{
-	int ebx; // will hold return value;
-
-	asm("pusha");
-
-	// select syscall
-	asm("mov %0, %%eax"::"m"(call)); 
-
-	// pass params
-	asm("mov %0,%%edx"::"m"(p1));
-	asm("mov %0,%%ecx"::"m"(p2));
-	asm("mov %0,%%ebx"::"m"(p3));
-
-	// interrrupt
-	asm("int $0x80");
+#include "usermode.h"
 
-	// get return value
-        asm("mov %%ebx, %0": "=b" (ebx));
+#include "syscalls.h"
+#include "kmalloc.h"
 
-	asm("popa");
+#include "lib/logger/log.h"
 
-	return ebx;
-}
-*/
+#include <stddef.h>
 
-/*
-int write(int file, char *ptr, int len) 
-{
-    return syscall(SYSCALL_WRITE,file,ptr,len);
-}
-*/
-/*
-int execve(char *name, char **argv, char **env) 
-{
-    return syscall(SYSCALL_EXECVE,name,argv,env);
-}
-*/
+//https://wiki.osdev.org/Task_State_Segment
+tss_struct sys_tss; //Define the TSS as a global structure
 
 void install_tss(int cpu_no){
 
     // now fill each value
     // set values necessary
-    sys_tss.ss0 = 0x10; //kernel data
+    sys_tss.ss0 = 0x10;            //kernel data
     sys_tss.esp0 = kballoc(4);
 
     // now set the IO bitmap (not necessary, so set above limit)       
     // sys_tss.iomap = ( unsigned short ) sizeof( tss_struct ); 
 }
 
-
 void switch_to_user_mode() 
 {
     asm_usermode();