cleaning up asm stuff and improving docs

21 files changed, 314 insertions, 223 deletions

diff --git a/asm/multiboot.s b/asm/multiboot.s
index 1d808a3..54cffbb 100644
--- a/asm/multiboot.s
+++ b/asm/multiboot.s
@@ -1,6 +1,10 @@
 # https://www.gnu.org/software/grub/manual/multiboot/multiboot.html#Boot-information-format
 # http://wiki.osdev.org/Bare_Bones
 
+# Fill Multiboot Haeder, init stack and call kernel_main passing to params:
+# eax - magic number
+# ebx - multiboot structure
+
 # Declare constants used for creating a multiboot header.
 .set ALIGN,    1<<0             # align loaded modules on page boundaries
 .set MEMINFO,  1<<1             # provide memory map
diff --git a/asm/x86.h b/asm/x86.h
new file mode 100644
index 0000000..8e6a741
--- /dev/null
+++ b/asm/x86.h
@@ -0,0 +1,100 @@
+#ifndef FOOLOS_X86_H
+#define FOOLOS_X86_H
+
+/**
+ * @file
+ *
+ * X86 32-bit Basics
+ * =================
+ *
+ * **All the functions are very specific to the targeted x86 architecture.**
+ *
+ * This is the header of our basic **x86** function definitions.
+ * Most of the functions are implemented in assembler in the file _asm/x86.s_,
+ * however a few short helper functions are defined in this header itself:
+ *
+ * * x86_set_page_directory()
+ * * x86_paging_enable()
+ * * x86_paging_disable()
+ *
+ *
+ * Reading and Writing Ports
+ * -------------------------
+ *
+ * The functions of the form x86_outX() and x86_inX(), where the X 
+ * indicates the value size allow reading and writing ports.
+ *
+ * * x86_outb() / x86_inb()
+ * * x86_outw() / x86_inw()
+ * * x86_outl() / x86_inl()
+ *
+ * The sizes are:
+ *
+ * * b - byte (8 bit)
+ * * w - word (16 bit)
+ * * l - double word (32 bit)
+ *
+ * Remember, that the port address is always 32 bits wide.
+ *
+ * Dependencies
+ * ------------
+ *
+ * All we need are uint32_t, uint16_t and uint8_t as provided by <stdint.h>
+ *
+ * References
+ * ----------
+ * * http://wiki.osdev.org/Interrupt_Service_Routines
+ * * https://wiki.osdev.org/CPU_Registers_x86
+ * * ...
+ *
+ */
+
+// we need uint32_t, uint16_t, uint8_t //
+#include <stdint.h>
+
+/** write byte to port */
+void     x86_outb (uint32_t port, uint8_t data);
+
+/** read byte from port */
+uint8_t  x86_inb  (uint32_t port);
+
+/** write word to port */
+void     x86_outw (uint32_t port, uint16_t data);
+
+/** read word from port */
+uint16_t x86_inw  (uint32_t port);
+
+/** write double word to port */
+void     x86_outl (uint32_t port, uint32_t data);
+
+/** read double word from port */
+uint32_t x86_inl  (uint32_t port);
+
+/** disable interrupts */
+void     x86_cli  ();
+
+/** enable interrupts */
+void     x86_sti  ();
+
+/** xchg - this can be used for semaphors and simlar */
+uint8_t  x86_xchg (uint8_t *addr, uint8_t val);
+
+/** invlpg - invalidate translation lookaside buffer */
+void     x86_invlpg(uint32_t addr);
+
+/** read value from control register specified by num */
+uint32_t x86_get_cr(uint8_t num);
+
+/** write given value to the control register specified by num */
+void     x86_set_cr(uint8_t num, uint32_t value);
+
+/** Set the address of the page directory. This is required **before** enabling paging */
+static inline void x86_set_page_directory(uint32_t pdir_addr) {x86_set_cr(3,pdir_addr);}
+
+/** Enable paging */
+static inline void x86_paging_enable()    {x86_set_cr(0,x86_get_cr(0)| 0x80000000);}
+
+/** Disable paging */
+static inline void x86_paging_disable()   {x86_set_cr(0,x86_get_cr(0)&~0x80000000);}
+
+#endif
diff --git a/asm/x86.s b/asm/x86.s
new file mode 100644
index 0000000..a5bcb1c
--- /dev/null
+++ b/asm/x86.s
@@ -0,0 +1,137 @@
+// Basic low-level x86 32-bit calls //
+
+// reading and writing ports
+
+.global x86_outb    // 8 bit out
+.global x86_inb     // 8 bit in
+.global x86_outw    // 16 bit out
+.global x86_inw     // 16 bit in
+.global x86_outl    // 32 bit out
+.global x86_inl     // 32 bit in
+
+// interrupts
+
+.global x86_cli    // disable interrupts
+.global x86_sti    // enable interrupts
+
+// xchg
+.global x86_xchg   // exchange (for semaphors etc.)
+
+// invlpg
+.global x86_invlpg // invalidate translation lookaside buffer (tlb)
+
+// control registers
+.global x86_get_cr
+.global x86_set_cr
+
+x86_outb:
+    mov 4(%esp), %edx
+    mov 8(%esp), %eax
+    outb %al,%dx
+    ret
+
+x86_inb:
+    mov 4(%esp), %edx
+    inb %dx,%al
+    ret
+
+x86_outw:
+    mov 4(%esp), %edx
+    mov 8(%esp), %eax
+    outw %ax,%dx
+    ret
+
+x86_inw:
+    mov 4(%esp), %edx
+    inw %dx,%ax
+    ret
+
+x86_outl:
+    mov 4(%esp), %edx
+    mov 8(%esp), %eax
+    outl %eax,%dx
+    ret
+
+x86_inl:
+    mov 4(%esp), %edx
+    inl %dx,%eax
+    ret
+
+x86_cli:
+    cli
+    ret
+
+x86_sti:
+    sti
+    ret
+
+x86_xchg:
+// --   uint8_t result;
+// -- 
+// --   // The + in "+m" denotes a read-modify-write operand.
+// --   asm volatile("lock xchgb %0, %1" :
+// --                "+m" (*addr), "=a" (result) :
+// --                "1" (val) :
+// --                "cc");
+// -- 
+// --   return result;
+// -- } 
+    ret
+
+x86_get_cr:
+    mov 4(%esp), %ecx
+    cmp %ecx,0
+    je get_cr0
+    cmp %ecx,2
+    je get_cr2
+    cmp %ecx,3
+    je get_cr3
+    cmp %ecx,4
+    je get_cr4
+    ret
+
+x86_set_cr:
+    mov 4(%esp), %eax
+    mov 8(%esp), %ecx
+    cmp %ecx,0
+    je set_cr0
+    cmp %ecx,2
+    je set_cr2
+    cmp %ecx,3
+    je set_cr3
+    cmp %ecx,4
+    je set_cr4
+    ret
+
+get_cr0:
+    mov %cr0,%eax
+    ret
+
+get_cr2:
+    mov %cr2,%eax
+    ret
+
+get_cr3:
+    mov %cr3,%eax
+    ret
+
+get_cr4:
+    mov %cr4,%eax
+    ret
+
+set_cr0:
+    mov %eax,%cr0
+    ret
+
+set_cr2:
+    mov %eax,%cr2
+    ret
+
+set_cr3:
+    mov %eax,%cr3
+    ret
+
+set_cr4:
+    mov %eax,%cr4
+    ret
+
diff --git a/doxy.cfg b/doxy.cfg
index ae15742..4df6982 100644
--- a/doxy.cfg
+++ b/doxy.cfg
@@ -453,7 +453,7 @@ EXTRACT_PACKAGE        = NO
 # included in the documentation.
 # The default value is: NO.
 
-EXTRACT_STATIC         = NO
+EXTRACT_STATIC         = YES
 
 # If the EXTRACT_LOCAL_CLASSES tag is set to YES, classes (and structs) defined
 # locally in source files will be included in the documentation. If set to NO,
@@ -873,7 +873,7 @@ RECURSIVE              = YES
 # Note that relative paths are relative to the directory from which doxygen is
 # run.
 
-EXCLUDE                = xxx userspace
+EXCLUDE                = xxx #userspace
 
 # The EXCLUDE_SYMLINKS tag can be used to select whether or not files or
 # directories that are symbolic links (a Unix file system feature) are excluded
@@ -995,32 +995,32 @@ USE_MDFILE_AS_MAINPAGE = README.md
 # also VERBATIM_HEADERS is set to NO.
 # The default value is: NO.
 
-SOURCE_BROWSER         = NO
+SOURCE_BROWSER         = YES
 
 # Setting the INLINE_SOURCES tag to YES will include the body of functions,
 # classes and enums directly into the documentation.
 # The default value is: NO.
 
-INLINE_SOURCES         = NO
+INLINE_SOURCES         = YES
 
 # Setting the STRIP_CODE_COMMENTS tag to YES will instruct doxygen to hide any
 # special comment blocks from generated source code fragments. Normal C, C++ and
 # Fortran comments will always remain visible.
 # The default value is: YES.
 
-STRIP_CODE_COMMENTS    = YES
+STRIP_CODE_COMMENTS    = NO
 
 # If the REFERENCED_BY_RELATION tag is set to YES then for each documented
 # function all documented functions referencing it will be listed.
 # The default value is: NO.
 
-REFERENCED_BY_RELATION = NO
+REFERENCED_BY_RELATION = YES
 
 # If the REFERENCES_RELATION tag is set to YES then for each documented function
 # all documented entities called/used by that function will be listed.
 # The default value is: NO.
 
-REFERENCES_RELATION    = NO
+REFERENCES_RELATION    = YES
 
 # If the REFERENCES_LINK_SOURCE tag is set to YES and SOURCE_BROWSER tag is set
 # to YES then the hyperlinks from functions in REFERENCES_RELATION and
diff --git a/driver/keyboard.c b/driver/keyboard.c
index 55e3c41..d35ef6d 100644
--- a/driver/keyboard.c
+++ b/driver/keyboard.c
@@ -3,7 +3,7 @@
 
 #define FOOLOS_MODULE_NAME "keyboard"
 #include <stdbool.h>
-#include "kernel/x86.h"
+#include "asm/x86.h"
 #include "lib/logger/log.h"
 
 static bool ctrl_l=false;
diff --git a/driver/mouse.c b/driver/mouse.c
index d4dbb56..23619a4 100644
--- a/driver/mouse.c
+++ b/driver/mouse.c
@@ -7,7 +7,7 @@
 #include "lib/logger/log.h"
 #include <stdint.h>
 
-#include "kernel/x86.h"
+#include "asm/x86.h"
 
 static volatile uint8_t mouse_cycle;
 static volatile uint8_t mouse_byte[3];
diff --git a/driver/pci.c b/driver/pci.c
index 677f445..a8cd68b 100644
--- a/driver/pci.c
+++ b/driver/pci.c
@@ -1,7 +1,7 @@
 #define FOOLOS_MODULE_NAME "pci"
 
 #include "kernel/kernel.h"
-#include "kernel/x86.h"
+#include "asm/x86.h"
 #include "e1000.h"
 #include "lib/logger/log.h"	// logger facilities
 
diff --git a/driver/serial.c b/driver/serial.c
index 1a36bf5..6e6a4bb 100644
--- a/driver/serial.c
+++ b/driver/serial.c
@@ -1,10 +1,13 @@
 #define FOOLOS_MODULE_NAME "serial"
 #include "serial.h"
 
-#define PORT 0x3f8   /* COM1 */
+#include "asm/x86.h" // provides x86_inb() and x86_outb()
 
-void serial_init() {
+/** COM1 Port */
+static const PORT=0x3f8;
 
+void serial_init()
+{
    x86_outb(PORT + 1, 0x00);    // Disable all interrupts
    x86_outb(PORT + 3, 0x80);    // Enable DLAB (set baud rate divisor)
    x86_outb(PORT + 0, 0x03);    // Set divisor to 3 (lo byte) 38400 baud
@@ -13,23 +16,26 @@ void serial_init() {
    x86_outb(PORT + 2, 0xC7);    // Enable FIFO, clear them, with 14-byte threshold
    x86_outb(PORT + 4, 0x0B);    // IRQs enabled, RTS/DSR set
 
-//   log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"COM 1 - initialized");
 }
 
-int serial_received() {
+static uint32_t serial_received()
+{
    return x86_inb(PORT + 5) & 1;
 }
  
-char serial_read() {
+uint8_t serial_read()
+{
    while (serial_received() == 0);
    return x86_inb(PORT);
 }
 
-int is_transmit_empty() {
+static uint32_t is_transmit_empty()
+{
    return x86_inb(PORT + 5) & 0x20;
 }
  
-void serial_write(char a) {
+void serial_write(uint8_t a)
+{
    while (is_transmit_empty() == 0);
    x86_outb(PORT,a);
 }
diff --git a/driver/serial.h b/driver/serial.h
index 2e10af8..c6841f2 100644
--- a/driver/serial.h
+++ b/driver/serial.h
@@ -1,18 +1,38 @@
+#ifndef FOOLOS_SERIAL_H
+#define FOOLOS_SERIAL_H
 /**
  * @file
- * Serial Port Driver for COM1
+ * MINIMALISTIC SERIAL PORT DRIVER for COM1
+ * ========================================
+ * Call serial_init() **once** before _reading_ or _writing_ with 
+ * serial_read() or serial_write(). 
  *
- * https://wiki.osdev.org/Serial_Ports
+ * Blocking
+ * --------
+ * Please note that the calls will block if the buffers 
+ * are full (and not read on the other end) _or_ no data is available 
+ * for reading.
  *
- * Call serial_init() once before reading and writing with serial_read()
- * and serial_write(). Note that reading and writing might block.
+ * Dependencies
+ * ------------
+ * The implmentation relies on x86_inb() and x86_outb() 
+ * to be defined in _asm/x86.h_.
+ *
+ * Reference
+ * ---------
+ * The implementation was ruthlessly copied from here: https://wiki.osdev.org/Serial_Ports
  */
 
+// We need uint8_t and uint_32t //
+#include <stdint.h>
+
 /** Initialize COM1 **/
 void serial_init();
 
 /** read one byte from COM1 (blocking) **/
-char serial_read();
+uint8_t serial_read();
  
 /** write one byte from COM1 (blocking) **/
-void serial_write(char a);
+void serial_write(uint8_t a);
+
+#endif
diff --git a/kernel/interrupts.c b/kernel/interrupts.c
index 74599c3..41d0a9c 100644
--- a/kernel/interrupts.c
+++ b/kernel/interrupts.c
@@ -5,7 +5,7 @@
 #include "asm/asm.h"
 #include "driver/mouse.h"
 #include "interrupts.h"
-#include "x86.h"
+#include "asm/x86.h"
 
 void errlog(uint32_t error_code)
 {
@@ -90,7 +90,7 @@ void exception_handle_14(uint32_t error_code,uint32_t eip,uint16_t cs,uint16_t u
    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"error_code_U/S: %d",error_code&4?1:0);
    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"error_code_RSVD: %d",error_code&8?1:0);
    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"error_code_I/D: %d",error_code&16?1:0);
-   log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"at addr: 0x%08X",x86_get_cr2());
+   log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"at addr: 0x%08X",x86_get_cr(2));
    
     deflog(eip,cs,flags);
    panic(FOOLOS_MODULE_NAME,"Exception: Fault: Page Fault");
@@ -166,8 +166,8 @@ void int_init(uint16_t sel)
     int_install();
 
     // now we can enable interrupts back again
-    // x86_int_enable();
-    x86_int_disable();
+    // x86_sti();
+    x86_cli();
 }
 
 void int_install()
diff --git a/kernel/kernel.c b/kernel/kernel.c
index 03862a9..b23a6d9 100644
--- a/kernel/kernel.c
+++ b/kernel/kernel.c
@@ -23,13 +23,11 @@
 /* F00L 0S Entry point (called directly from asm/multiboot.asm */
 void kernel_main(uint32_t eax,uint32_t ebx)
 {
-    // SERIAL PORT
     serial_init();
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"COM 1 - initialized");
 
-    // PR
-    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"%s - compiled on %s at %s",
-        KERNEL_NAME,__DATE__,__TIME__);
-    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"git revision: %s",GIT_REVISION);
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"%s - BUILD: git-%s (%s %s)",
+        KERNEL_NAME,GIT_REVISION,__DATE__,__TIME__);
 
     // PIT TIMER
     timer_init();
diff --git a/kernel/mp.c b/kernel/mp.c
index abea5cb..76754b8 100644
--- a/kernel/mp.c
+++ b/kernel/mp.c
@@ -2,7 +2,7 @@
 
 #include <stdbool.h>
 
-#include "x86.h"
+#include "asm/x86.h"
 #include "lib/logger/log.h"	// logger facilities
 #include "smp.h"
 
diff --git a/kernel/ringbuffer.c b/kernel/ringbuffer.c
index 31185dc..099e96a 100644
--- a/kernel/ringbuffer.c
+++ b/kernel/ringbuffer.c
@@ -20,11 +20,11 @@ ringbuffer ringbuffer_init(uint32_t size)
 
 bool ringbuffer_put(ringbuffer* f,uint8_t c)
 {
-    x86_int_disable();
+    x86_cli();
 
     if((f->back-1+f->size)%f->size==f->front)
     {
-	x86_int_enable();
+	x86_sti();
 	return false;
     }
 
@@ -33,30 +33,30 @@ bool ringbuffer_put(ringbuffer* f,uint8_t c)
     f->back+=f->size;
     f->back%=f->size;
 
-    x86_int_enable();
+    x86_sti();
     return true;
 }
 
 bool ringbuffer_has(ringbuffer* f)
 {
-    x86_int_disable();
+    x86_cli();
     bool res=true;
 
     if(f->front==f->back)
 	res=false;
 
-    x86_int_enable();
+    x86_sti();
     return res;
 }
 
 uint8_t ringbuffer_get(ringbuffer* f) // non blocking . please check first
 {
-    x86_int_disable();
+    x86_cli();
     char c;
 
     if(f->front==f->back)
     {
-	x86_int_enable();
+	x86_sti();
 	return ' ';
     }
 
@@ -66,6 +66,6 @@ uint8_t ringbuffer_get(ringbuffer* f) // non blocking . please check first
     f->front+=f->size;
     f->front%=f->size;
 
-    x86_int_enable();
+    x86_sti();
     return c;
 }
diff --git a/kernel/smp.c b/kernel/smp.c
index 08af652..a562df3 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -10,7 +10,7 @@
 #include "smp.h"
 #include "mem.h"
 #include "spinlock.h"
-#include "x86.h"
+#include "asm/x86.h"
 
 #define FOOLOS_APIC_SPUR_INT 0x00f0
 #define FOOLOS_APIC_INT_COMMAND_LOW 0x0300
@@ -27,7 +27,7 @@ uint32_t local_apic_addr;
 void smp_main()
 {
 
-    x86_int_disable();
+    x86_cli();
     while(1);
 
    // log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"local apic_addr:0x%08X",local_apic_addr);
diff --git a/kernel/spinlock.c b/kernel/spinlock.c
index f97b7db..2a546a8 100644
--- a/kernel/spinlock.c
+++ b/kernel/spinlock.c
@@ -4,7 +4,7 @@
 #include "kernel.h"
 
 #include "lib/logger/log.h"
-#include "x86.h"
+#include "asm/x86.h"
 
 // https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html
 
diff --git a/kernel/task.c b/kernel/task.c
index be9ddd9..3c1e067 100644
--- a/kernel/task.c
+++ b/kernel/task.c
@@ -7,7 +7,7 @@
 #include "lib/logger/log.h"	// logger facilities
 #include "mem.h"
 #include "timer.h"
-#include "x86.h"
+#include "asm/x86.h"
 
 #include "vmem.h"
 #include "syscalls.h"
diff --git a/kernel/timer.c b/kernel/timer.c
index 3f7ab0f..e5e26b4 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -32,7 +32,7 @@
 #define FOOLOS_MODULE_NAME "timer"
 
 #include "timer.h"
-#include "x86.h"
+#include "asm/x86.h"
 #include "lib/logger/log.h"
 
 // TODO: use mutex? do we need volatile at all!??
diff --git a/kernel/vmem.c b/kernel/vmem.c
index 3d3456b..fb19e75 100644
--- a/kernel/vmem.c
+++ b/kernel/vmem.c
@@ -3,7 +3,7 @@
 #include <stdlib.h>
 
 #include "kernel.h"
-#include "x86.h"
+#include "asm/x86.h"
 #include "mem.h"
 #include "vmem.h"
 #include "lib/logger/log.h"	// logger facilities
@@ -491,7 +491,7 @@ pdirectory* vmem_new_space_dir(pdirectory *copy_dir)
 
 void vmem_set_dir(pdirectory *dir)
 {
-    x86_set_pdbr(dir);
+    x86_set_page_directory(dir);
 }
 
 pdirectory* vmem_init(uint32_t kernel_blocks, uint32_t frameb_addr)
diff --git a/kernel/x86.c b/kernel/x86.c
deleted file mode 100644
index d664657..0000000
--- a/kernel/x86.c
+++ /dev/null
@@ -1,140 +0,0 @@
-#define FOOLOS_MODULE_NAME "x86"
-
-#include "x86.h"
-#include "timer.h"
-#include "lib/logger/log.h"
-
-//
-// suffix (b, w, l, q for byte, word, dword, and qword).
-//
-
-// disable interrupts
-void x86_int_disable()
-{
-    asm volatile("cli");
-}
-
-// enable interrupts
-void x86_int_enable()
-{
-    asm volatile("sti");
-}
-
-// get control registers (cr0-cr4)
-uint32_t x86_get_cr0()
-{
-    uint32_t cr;
-    asm volatile("mov %%cr0, %0": "=b"(cr));
-    return cr;
-}
-
-uint32_t x86_get_cr1()
-{
-    uint32_t cr=0;
-    
-    // reading the reserved cr1 register results in crash.
-    // (at least on emulators)
-    // asm volatile("mov %%cr1, %0": "=b"(cr));
-    
-    return cr;
-}
-
-uint32_t x86_get_cr2()
-{
-    uint32_t cr;
-    asm volatile("mov %%cr2, %0": "=b"(cr));
-    return cr;
-}
-
-uint32_t x86_get_cr3()
-{
-    uint32_t cr=0;
-    asm volatile("mov %%cr3, %0": "=b"(cr));
-    return cr;
-}
-
-uint32_t x86_get_cr4()
-{
-    uint32_t cr;
-    asm volatile("mov %%cr4, %0": "=b"(cr));
-    return cr;
-}
-void x86_outb(uint32_t port, uint8_t data)
-{
-    asm volatile("outb %0,%w1" : : "a" (data), "d" (port));
-}
-
-uint8_t x86_inb(uint32_t port)
-{
-    uint8_t data;
-    asm volatile("inb %w1,%0" : "=a" (data) : "d" (port));
-    return data;
-}
-
-void x86_outw(uint32_t port, uint16_t data)
-{
-    asm volatile("outw %0,%w1" : : "a" (data), "d" (port));
-}
-
-uint16_t x86_inw(uint32_t port)
-{
-    uint16_t data;
-    asm volatile("inw %w1,%0" : "=a" (data) : "d" (port));
-    return data;
-}
-
-void x86_outl(uint32_t port, uint32_t data)
-{
-    asm volatile("outl %0,%w1" : : "a" (data), "d" (port));
-}
-
-uint32_t x86_inl(uint32_t port)
-{
-    uint32_t data;
-    asm volatile("inl %w1,%0" : "=a" (data) : "d" (port));
-    return data;
-}
-
-
-void x86_set_pdbr(uint32_t addr) 
-{
-    asm volatile("mov %0, %%cr3":: "b"(addr));
-
-}
-
-// enable PT bit in CR0
-void x86_paging_enable()
-{
-    uint32_t cr0=x86_get_cr0();
-    cr0 |= 0x80000000; // enable paging 
-    asm volatile("mov %0, %%cr0":: "b"(cr0));
-}
-
-// disable PT bit in CR0
-void x86_paging_disable()
-{
-    uint32_t cr0=x86_get_cr0();
-    cr0 &= ~0x80000000;
-    asm volatile("mov %0, %%cr0":: "b"(cr0));
-}
-
-void x86_flush_tlb(uint32_t addr)
-{
-    asm volatile("invlpg (%0)" ::"r" (addr) : "memory");
-}
-
-//xchg
-uint8_t x86_xchg(uint8_t *addr, uint8_t val)
-{   
-
-  uint8_t result;
-
-  // The + in "+m" denotes a read-modify-write operand.
-  asm volatile("lock xchgb %0, %1" :
-               "+m" (*addr), "=a" (result) :
-               "1" (val) :
-               "cc");
-
-  //log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"xchg val:%d with addr:0x%08X : result: %d",val,addr,result);
-  return result;
-} 
diff --git a/kernel/x86.h b/kernel/x86.h
deleted file mode 100644
index b634722..0000000
--- a/kernel/x86.h
+++ /dev/null
@@ -1,34 +0,0 @@
-#ifndef FOOLOS_X86_H
-#define FOOLOS_X86_H
-
-#include <stdint.h>
-
-// http://wiki.osdev.org/Interrupt_Service_Routines
-
-// TODO : Real sleep()!
-
-void x86_outb(uint32_t port, uint8_t data);
-uint8_t x86_inb(uint32_t port);
-
-void x86_outw(uint32_t port, uint16_t data);
-uint16_t x86_inw(uint32_t port);
-
-void x86_outl(uint32_t port, uint32_t data);
-uint32_t x86_inl(uint32_t port);
-
-void x86_set_pdbr(uint32_t addr);
-void x86_paging_enable();
-void x86_flush_tlb(uint32_t addr);
-
-void x86_int_enable();
-void x86_int_disable();
-
-uint32_t x86_get_cr0();
-uint32_t x86_get_cr1();
-uint32_t x86_get_cr2();
-uint32_t x86_get_cr3();
-uint32_t x86_get_cr4();
-
-uint8_t x86_xchg(uint8_t *addr, uint8_t val);
-
-#endif
diff --git a/userspace/Makefile b/userspace/Makefile
index 85c7982..a8aa418 100644
--- a/userspace/Makefile
+++ b/userspace/Makefile
@@ -1,4 +1,4 @@
-IMAGESIZE=30000 #ext2.img size in Kb (30Megs)
+IMAGESIZE=10000 #ext2.img size in Kb
 
 #######################