@@ -0,0 +1,4 @@
+.RECIPEPREFIX = >
+.PHONY: build
+build:
+> 

@@ -0,0 +1,4 @@
+.RECIPEPREFIX = >
+.PHONY: build
+build:
+> 

@@ -0,0 +1,4 @@
+.RECIPEPREFIX = >
+.PHONY: build
+build:
+> 

@@ -0,0 +1,16 @@
+OUTPUT_ARCH(i386)
+OUTPUT_FORMAT(elf32-i386)
+
+MEMORY
+{
+  HEADER :   ORIGIN = 0x00000000, LENGTH = 0x10000000
+  CODE :   ORIGIN = 0x10000000, LENGTH = 0xB0000000
+}
+
+SECTIONS
+{
+  .text : AT(0x0000)
+  {
+    */start.c.o(.*)
+  } >CODE
+}

@@ -0,0 +1,27 @@
+.RECIPEPREFIX = >
+
+S_OBJECTS = $(patsubst %.s,$(LOCAL_BUILD)/%.s.o,$(wildcard *.s))
+C_OBJECTS = $(patsubst %.c,$(LOCAL_BUILD)/%.c.o,$(wildcard *.c))
+OBJECTS = $(S_OBJECTS) $(C_OBJECTS)
+
+LOCAL_BUILD = $(GLOBAL_BUILD)/apps
+
+SUBDIRS = $(wildcard */.)
+
+.PHONY: build
+build: folder $(SUBDIRS) $(OBJECTS)
+> $(GCC_PREFIX)ld -T link.txt $(wildcard $(LOCAL_BUILD)/*.o) -o $(GLOBAL_BUILD)/apps.o --oformat elf32-i386
+
+.PHONY: folder
+folder:
+> @mkdir $(LOCAL_BUILD) 2> /dev/null; true
+
+.PHONY: $(SUBDIRS)
+$(SUBDIRS):
+> make -C $@ GLOBAL_BUILD=$(LOCAL_BUILD) build
+
+$(LOCAL_BUILD)/%.s.o: %.s
+> $(GCC_PREFIX)as -o $@ $<
+
+$(LOCAL_BUILD)/%.c.o: %.c $(wildcard *.h)
+> $(GCC_PREFIX)gcc -c -I$(INCLUDE_DIR) --prefix=$(GCC_PREFIX) $(GCC_OPTIONS) -o $@ $<

@@ -0,0 +1,24 @@
+#include <stdint.h>
+
+/*!
+ * Performs a syscall.
+ */
+__attribute__((always_inline)) inline int syscall(int eax, int ebx, int ecx, int edx) {
+    int res;
+    __asm__ volatile (  "mov %1, %%eax;"
+                        "mov %2, %%ebx;"
+                        "mov %3, %%ecx;"
+                        "mov %4, %%edx;"
+                        "int $0x30;"
+                        "mov %%eax, %0;" : "=m" (res) : "" (eax), "" (ebx), "" (ecx), "" (edx) : "eax", "ebx", "ecx", "edx");
+    return res;
+}
+
+int start(void) {
+    uint32_t eip, esp, ebp;
+    __asm__ volatile ("call jump; jump: pop %0; mov %%esp, %1; mov %%ebp, %2" : "=m" (eip), "=m" (esp), "=m" (ebp));
+
+    syscall(0, eip, esp, ebp);
+
+    while(1);
+}

@@ -42,7 +42,9 @@ # TODO:
   #  - activate A20 gate
 
   # reset bootdrive
+  mov $10, %cx
 reset:
+  push %cx
   movw $reset_msg, %si
   call print
   movw $bootdrive_msg, %si
@@ -50,7 +52,11 @@ call print
 
   movb $0x00, %ah
   int $0x13
+  pop %cx
+  jnc reset_end
+  loop reset
   jc error
+reset_end:
 
   movw $done_msg, %si
   call print
@@ -60,7 +66,9 @@ #   (NOTE: this code can only be jumped to after loading the global descriptor table
   #          because it uses absolute adresses larger than 16 bit)
   #   (NOTE2: this routine only loads 0x48 sectors of the second stage into memory
   #          and is in general pretty whacky. should be replaced with sth more serious)
+  mov $10, %cx
 load:
+  push %cx
   movw $load_msg, %si
   call print
 
@@ -74,7 +82,11 @@ movb $0x02, %cl     # sector
   movb $0x00, %dh     # head
   # dl (drive) keep as is
   int $0x13
+  pop %cx
+  jnc load_end
+  loop load
   jc error
+load_end:
 
   movw $done_msg, %si
   call print

@@ -14,6 +14,10 @@ extern uint8_t __KERNEL_VMA;
 extern uint8_t __KERNEL_LMA;
 extern uint8_t __KERNEL_SIZE;
 
+extern uint8_t __APP_VMA;
+extern uint8_t __APP_LMA;
+extern uint8_t __APP_SIZE;
+
 #define SS_VMA (&__SS_VMA)
 #define SS_LMA (&__SS_LMA)
 #define SS_SIZE (uint32_t)(&__SS_SIZE)
@@ -21,5 +25,9 @@
 #define KERNEL_VMA (&__KERNEL_VMA)
 #define KERNEL_LMA (&__KERNEL_LMA)
 #define KERNEL_SIZE (uint32_t)(&__KERNEL_SIZE)
+
+#define APP_VMA (&__APP_VMA)
+#define APP_LMA (&__APP_LMA)
+#define APP_SIZE (uint32_t)(&__APP_SIZE)
 
 #endif

@@ -41,7 +41,7 @@ void copy_kernel(void) {
     uint8_t *kernel_dest = (uint8_t*)0x00100000;
     uint8_t *kernel_src = (SS_VMA + (KERNEL_LMA - SS_LMA));
     
-    for (uint32_t i = 0; i < KERNEL_SIZE; i++) {
+    for (uint32_t i = 0; i < KERNEL_SIZE + APP_SIZE; i++) {
         kernel_dest[i] = kernel_src[i];
     }
 }

@@ -10,6 +10,8 @@ #include "cedos/sched/process.h"
 
 #include "cedos/mm/paging.h"
 
+#define SCHED_INTERVAL (0xFFFF)
+
 /*!
  * Structure of the process stack when the scheduler is executed.
  */
@@ -30,7 +32,7 @@
 /*!
  * Executes a task.
  */
-PROCESS_ID sched_exec(PHYS_ADDR page_dir, PROCESS_MAIN *entry, const char *name);
+PROCESS_ID sched_exec(VIRT_ADDR code, uint32_t code_len, PROCESS_MAIN *entry, const char *name);
 
 /*!
  * Return the ID of the current process.

@@ -14,6 +14,10 @@ extern uint8_t __KERNEL_VMA;
 extern uint8_t __KERNEL_LMA;
 extern uint8_t __KERNEL_SIZE;
 
+extern uint8_t __APP_VMA;
+extern uint8_t __APP_LMA;
+extern uint8_t __APP_SIZE;
+
 #define SS_VMA (&__SS_VMA)
 #define SS_LMA (&__SS_LMA)
 #define SS_SIZE (uint32_t)(&__SS_SIZE)
@@ -21,5 +25,9 @@
 #define KERNEL_VMA (&__KERNEL_VMA)
 #define KERNEL_LMA (&__KERNEL_LMA)
 #define KERNEL_SIZE (uint32_t)(&__KERNEL_SIZE)
+
+#define APP_VMA (&__APP_VMA)
+#define APP_LMA (&__APP_LMA)
+#define APP_SIZE (uint32_t)(&__APP_SIZE)
 
 #endif

@@ -49,6 +49,7 @@ rek_print_uint((unsigned int)value);
 }
 
 void memdump(void* start, uint32_t size) {
+    crit_enter();
     uint8_t* _start = (uint8_t*)((uint32_t)start & 0xFFFFFFF0);
     uint8_t* _end = (uint8_t*)(((uint32_t)start + size + 0xF) & 0xFFFFFFF0);
 
@@ -74,6 +75,8 @@ }
         }
         core_con->write_c('\n');
     }
+
+    crit_exit();
 }
 
 void stackdump(void) {
@@ -103,8 +106,8 @@ "=m" (edi),
                         "=m" (esp),
                         "=m" (ebp));
 
-    printk(" EAX=%i EBX=%i ECX=%i EDX=%i\n", eax, ebx, ecx, edx);
-    printk(" ESI=%i EDI=%i ESP=%i EBP=%i\n", esi, edi, esp, ebp);
+    printk(" EAX=%X EBX=%X ECX=%X EDX=%X\n", eax, ebx, ecx, edx);
+    printk(" ESI=%X EDI=%X ESP=%X EBP=%X\n", esi, edi, esp, ebp);
 }
 
 void printk(const char* fmt, ...) {
@@ -127,6 +130,9 @@ print_int(va_arg(args, int));
             state = STATE_DEFAULT;
         } else if (state == STATE_ARGUMENT && *fmt == 'u') {
             print_uint(va_arg(args, unsigned int));
+            state = STATE_DEFAULT;
+        } else if (state == STATE_ARGUMENT && *fmt == 'p') {
+            print_uint32(va_arg(args, uint32_t));
             state = STATE_DEFAULT;
         } else if (state == STATE_ARGUMENT && *fmt == 's') {
             const char* string = va_arg(args, const char*);

@@ -12,6 +12,7 @@ #include "cedos/pic.h"
 #include "cedos/pit.h"
 #include "cedos/core.h"
 
+#include "linker.h"
 #include "assert.h"
 
 int os_init(void) {
@@ -93,50 +94,33 @@ crit_exit();
     }
 }
 
-int fibonacci(void) {
-    int a = 0, b = 1;
+int sysinit(void) {
+    uint8_t scancode = 0;
 
-    while (1) {
-        int tmp = a + b;
-        b = a;
-        a = tmp;
-        printk("%i\n", a);
-        sched_yield();
-    }
-}
+    memdump((VIRT_ADDR)0x10000000, 0x3000);
 
-int leaf(void) {
-    while (1) { hlt(); }
-}
+    //syscall(0, 0xCAFEBABE, 0xDEADBEEF, 0x42069420);
 
-int node(void) {
-    for (int i = 0; i < 8; i++) {
-        sched_yield();
-    }
+    printk("PRESS ENTER:");
 
-    sched_exec(create_empty_page_dir(), leaf, "leaf");
+    do {
+        scancode = ps2_kb.read();
+        printk("%c", scancode);
+    } while (scancode != 0x1C);
 
-    while (1) { hlt(); }
-}
+    printk("THANKS, NOW PRESS ESC TO EXIT:");
 
-int sysinit(void) {
-    uint8_t scancode = 0;
-
-    syscall(1, 0xCAFEBABE, 0xDEADBEEF, 0x42069420);
-
-    printk("PRESS ENTER\n");
-
-    while (scancode != 0x1C) {
+    do {
         scancode = ps2_kb.read();
         printk("%c", scancode);
-    }
+    } while (scancode != 0x01);
 
-    printk("THANKS\n");
+    syscall(1, 0, 0, 0);
     
-    while (1) {
-        printk("x");
-        hlt();
-    }
+    //while (1) {
+    //    printk("x");
+    //    hlt();
+    //}
 
     //sched_exec(create_empty_page_dir(), fibonacci, "fibonacci");
     //sched_exec(create_empty_page_dir(), node, "node");
@@ -150,7 +134,7 @@ infodump();
 
     // create test tasks
     printk("Creating tasks.\n");
-    sched_exec(create_empty_page_dir(), sysinit, "sysinit");
+    sched_exec(SS_VMA + (APP_LMA - SS_LMA), APP_SIZE, APP_VMA, "sysinit");
 
     printk("Starting scheduler.\n");
     sched_start();

@@ -57,7 +57,7 @@ /*!
 * WARNING: This method assumes the target page directory has already been mounted
 * to the second to last page directory entry
 */
-int map_page_to(PHYS_ADDR page_addr, uint32_t dir_index, uint32_t table_index, uint32_t flags) {
+int force_map_page_to(PHYS_ADDR page_addr, uint32_t dir_index, uint32_t table_index, uint32_t flags) {
     PAGE_DIR_ENTRY* page_dir = PAGE_DIR_ALT_MAPPED_ADDR;
     PAGE_TABLE_ENTRY* page_table = PAGE_TABLE_ALT_MAPPED_ADDR(dir_index);
     
@@ -69,32 +69,16 @@ PHYS_ADDR new_page_table = get_free_page();
         page_dir[dir_index] = MAKE_PAGE_ENTRY(new_page_table, PAGE_TABLE_FLAGS);
     }
 
-    if (!is_present(page_table[table_index])) {
-        // map page
-        page_table[table_index] = MAKE_PAGE_ENTRY(page_addr, flags);
-        return 1;
-    } else {
-        // didn't works
-        return 0;
-    }
+    // map page
+    page_table[table_index] = MAKE_PAGE_ENTRY(page_addr, flags);
+    inv_all_pages();
+    return 1;
 }
 
-int map_page_to_this(PHYS_ADDR page_addr, uint32_t dir_index, uint32_t table_index, uint32_t flags) {
-    PAGE_DIR_ENTRY* page_dir = PAGE_DIR_MAPPED_ADDR;
-    PAGE_TABLE_ENTRY* page_table = PAGE_TABLE_MAPPED_ADDR(dir_index);
-
-    if (!is_present(page_dir[dir_index])) {
-        // acquire new page table
-        void *new_page_table = get_free_page();
-        page_dir[dir_index] = MAKE_PAGE_ENTRY(new_page_table, PAGE_TABLE_FLAGS);
-    }
-
-    if (!is_present(page_table[table_index])) {
-        // map page
-        page_table[table_index] = MAKE_PAGE_ENTRY(page_addr, flags);
-        return 1;
+int map_page_to(PHYS_ADDR page_addr, uint32_t dir_index, uint32_t table_index, uint32_t flags) {
+    if (is_addr_available(dir_index, table_index)) {
+        force_map_page_to(page_addr, dir_index, table_index, flags);
     } else {
-        // didn't works
         return 0;
     }
 }
@@ -111,21 +95,41 @@ }
 
     // map page
     page_table[table_index] = MAKE_PAGE_ENTRY(page_addr, flags);
+    inv_all_pages();
     return 1;
 }
 
+int map_page_to_this(PHYS_ADDR page_addr, uint32_t dir_index, uint32_t table_index, uint32_t flags) {
+    if (is_addr_available(dir_index, table_index)) {
+        force_map_page_to_this(page_addr, dir_index, table_index, flags);
+    } else {
+        return 0;
+    }
+}
+
 size_t copy_to_pdir(VIRT_ADDR src, size_t length, PHYS_ADDR pdir, VIRT_ADDR dest) {
-    PHYS_ADDR page = get_free_page();
     VIRT_ADDR mount_dest = 0xe0000000;
-    force_map_page_to_this(page, PAGE_DIR_INDEX(mount_dest), PAGE_TABLE_INDEX(mount_dest), PAGE_TABLE_FLAGS);
-    uint32_t offset = ((uint32_t)dest) & 0xFFF;
+    mount_page_dir(pdir);
+    PHYS_ADDR page;
+
+    while (length != 0) {
+        page = get_free_page();
+        force_map_page_to_this(page, PAGE_DIR_INDEX(mount_dest), PAGE_TABLE_INDEX(mount_dest), PAGE_TABLE_FLAGS);
+        force_map_page_to(page, PAGE_DIR_INDEX(dest), PAGE_TABLE_INDEX(dest), PAGE_TABLE_FLAGS);
+
+        uint32_t offset = ((uint32_t)dest % PAGE_SIZE);
+        uint32_t part_length = (offset + length <= PAGE_SIZE) ? length : PAGE_SIZE - offset;
+
+        printk("src=%p dest=%p length=%i offset=%i plen=%i\n", src, dest, length, offset, part_length);
 
-    for (uint32_t i = 0; i < length; i++) {
-        ((uint8_t*)mount_dest)[offset + i] = ((uint8_t*)src)[i];
+        for (uint32_t i = 0; i < part_length; i++) {
+            ((uint8_t*)mount_dest)[offset + i] = ((uint8_t*)src)[i];
+        }
+
+        dest += part_length;
+        src += part_length;
+        length -= part_length;
     }
-
-    mount_page_dir(pdir);
-    map_page_to(page, PAGE_DIR_INDEX(dest), PAGE_TABLE_INDEX(dest), PAGE_TABLE_FLAGS);
 }
 
 int map_range_to(PHYS_ADDR page_dir, VIRT_ADDR dest, PHYS_ADDR src, uint32_t page_count, uint32_t flags) {
@@ -178,7 +182,7 @@ // map to itself
     page_dir[PAGE_ENTRY_COUNT - 1] = MAKE_PAGE_ENTRY(page_dir_phys, PAGE_TABLE_FLAGS);
     
     page_dir = PAGE_DIR_ALT_MAPPED_ADDR;
-    
+
     // identity map first 4MB
     page_dir[0] = PAGE_DIR_MAPPED_ADDR[0];
 
@@ -191,9 +195,10 @@
 EXCEPTION(page_fault_isr, frame, error_code) {
     volatile VIRT_ADDR faulty_addr;
     __asm__ volatile ("mov %%cr2, %0" : "=a" (faulty_addr));
+    //if (PAGE_DIR_INDEX(faulty_addr) >= PAGE_ENTRY_COUNT - 2) { return; }
     printk("PAGE FAULT: %X\n", faulty_addr);
     PHYS_ADDR new_page = get_free_page();
-    map_page_to_this(new_page, PAGE_DIR_INDEX(faulty_addr), PAGE_TABLE_INDEX(faulty_addr), PAGE_TABLE_FLAGS);
+    force_map_page_to_this(new_page, PAGE_DIR_INDEX(faulty_addr), PAGE_TABLE_INDEX(faulty_addr), PAGE_TABLE_FLAGS);
     // dump registers to stdout
 }
 

@@ -15,10 +15,9 @@
 #include "assembly.h"
 
 #define KERNEL_PRIVATE_STACK (void*)(0xC0600000)
+#define USER_STACK (void*)(0xC0000000)
 
 #define PROCESS_STD_EFLAGS (0x00000286)
-
-#define SCHED_INTERVAL (0xFFFF)
 
 PROCESS* get_slot(void) {
     static PROCESS free_slots[8];
@@ -28,21 +27,30 @@ }
 
 PROCESS_ID current_pid;
 
+PROCESS_ID get_current_process(void) {
+    return current_pid;
+}
+
 int sched_dispatcher(void);
 
 /*!
  * Executes a task.
  */
-PROCESS_ID sched_exec(PHYS_ADDR page_dir, PROCESS_MAIN *entry, const char *name) {
+PROCESS_ID sched_exec(VIRT_ADDR code, uint32_t code_len, PROCESS_MAIN *entry, const char *name) {
     crit_enter();
 
+    PHYS_ADDR page_dir = create_empty_page_dir();
+
+    // copy app code
+    copy_to_pdir(code, code_len, page_dir, (VIRT_ADDR)0x10000000);
+
     // set process context
     PROCESS *p = get_slot();
     p->name = name;
     p->page_dir = page_dir;
     p->eip = sched_dispatcher;
-    p->ebp = KERNEL_PRIVATE_STACK;
-    p->esp = KERNEL_PRIVATE_STACK - sizeof(SCHED_FRAME);
+    p->ebp = USER_STACK;
+    p->esp = USER_STACK - sizeof(SCHED_FRAME);
     p->eflags = PROCESS_STD_EFLAGS;
     p->entry = entry;
     p->state = PSTATE_READY;
@@ -134,7 +142,7 @@
     current_pid = 0;
 
     // create idle process
-    sched_exec(create_empty_page_dir(), idle, "idle");
+    sched_exec(0, 0, idle, "idle");
 
     return 1;
 }

@@ -1,11 +1,17 @@
 #include "cedos/interrupts.h"
 #include "cedos/core.h"
+#include "cedos/sched/sched.h"
 
 void test(uint32_t ebx, uint32_t ecx, uint32_t edx) {
     printk("SYSCALL 0x01: EBX=%X ECX=%X EDX=%X\n", ebx, ecx, edx);
 }
 
-void* SYSCALL_TABLE[] = { hard_reset, test };
+void* SYSCALL_TABLE[] = { 
+        test, 
+        hard_reset, 
+        sched_yield, 
+        get_current_process 
+    };
 
 extern void syscall_interrupt(void);
 

@@ -11,7 +11,7 @@
   mov $SYSCALL_TABLE, %ecx
   mov (%ecx, %eax, 4), %eax
 
-  call %eax
+  call *%eax
 
   // restore stack
   add $12, %esp

@@ -34,7 +34,7 @@ } >KERNEL
 
   APPLICATION : AT(LOADADDR(KERNEL) + SIZEOF(KERNEL))
   {
-    
+    */apps.o(.*)
   } >APPLICATION
 
   .bss : AT(LOADADDR(APPLICATION) + SIZEOF(APPLICATION))

@@ -23,6 +23,7 @@ build:
 > @mkdir $(LOCAL_BUILD) 2> /dev/null; true
 > $(MAKE) GLOBAL_BUILD=$(LOCAL_BUILD) -C boot build
 > $(MAKE) GLOBAL_BUILD=$(LOCAL_BUILD) -C kernel build
+> $(MAKE) GLOBAL_BUILD=$(LOCAL_BUILD) -C apps build
 > $(GCC_PREFIX)ld $(LOCAL_BUILD)/*.o -T link.txt -Map=$(DEBUG_DIR)/mapfile.txt -o $(GLOBAL_BUILD)/base.o
 > $(GCC_PREFIX)objcopy --only-keep-debug $(GLOBAL_BUILD)/base.o $(DEBUG_DIR)/base.sym
 > $(GCC_PREFIX)objcopy -O binary $(GLOBAL_BUILD)/base.o $(GLOBAL_BUILD)/base.img