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Code: Select all

syscall_irq:
   push byte 0
   push byte 48

   jmp irq_common_stub


extern irq_handler


irq_common_stub:
   cld
   pushad
   push ds
   push es
   push fs
   push gs

   mov eax, [current]
   mov [eax], esp

   mov ax, 0x10
   mov ds, ax
   mov es, ax
   mov fs, ax
   mov gs, ax

   push esp

   call irq_handler

   add esp, 4

   jmp common_end

global switch_to

switch_to:
   mov eax, [current]   
   mov esp, [eax]   

   mov ebx, [eax+8];put content of the k-stack field into ebx.
   mov [morts_tss+4],ebx ;update system tss. (esp)

   mov ebx, [eax+20]
   mov cr3, ebx

common_end:

   mov eax, [esp]
   cmp eax, 40
   jl master_reg

   mov al, 0x20
   out 0xA0, al

master_reg:
   mov al, 0x20
   out 0x20, al

   pop gs    
   pop fs
   pop es
   pop ds
   popad

   add esp, 8

   iret

Code: Select all

struct task_struct {
   uint32_t esp;
   uint32_t ss;
   uint32_t kstack;
   uint32_t kstack_mem;
   uint32_t ustack;
   uint32_t cr3;
   long state;
   long counter;
   long priority;
   uint8_t signal[NSIG];
   fn_ptr sig_restore;
   fn_ptr sig_fns[NSIG];
   int exit_code;
   unsigned long brk,start_stack;
   long pid,parent,pgrp,session,leader;
   unsigned short uid,euid,suid;
   unsigned short gid,egid,sgid;
   long alarm;
   long utime,stime,cutime,cstime,start_time;
   unsigned short used_math;
   int tty;
   unsigned short umask;
   struct ext2fs_inode_table *pwd; // TODO: should be a vfs node
   struct ext2fs_fs_data *pwd_fsd;
   struct ext2fs_inode_table *root; // TODO: should be a vfs node
   struct ext2fs_fs_data *root_fsd;
   unsigned long close_on_exec;
   struct file *filp[NR_OPEN];

   struct task_struct *next;
   struct task_struct *prev;
};