/*
* get system call
*/
static void
syscall_handler (struct intr_frame *f)
{
int *esp = (int *)syscall_user_to_kernel_vaddr(f->esp);
switch(*esp)
{
case SYS_WRITE:
syscall_write(f);
break;
case SYS_EXIT:
syscall_exit(f);
break;
case SYS_HALT:
syscall_halt(f);
break;
case SYS_EXEC:
syscall_exec(f);
break;
case SYS_CREATE:
syscall_create(f);
break;
case SYS_REMOVE:
syscall_remove(f);
break;
case SYS_OPEN:
syscall_open(f);
break;
case SYS_FILESIZE:
syscall_filesize(f);
break;
case SYS_READ:
syscall_read(f);
break;
case SYS_SEEK:
syscall_seek(f);
break;
case SYS_TELL:
syscall_tell(f);
break;
case SYS_CLOSE:
syscall_close(f);
break;
case SYS_WAIT:
syscall_wait(f);
break;
}
}
static void
syscall_handler (struct intr_frame *f)
{
int syscall_num;
VALIDATE_AND_GET_ARG (f->esp, syscall_num, f);
void *cur_sp = f->esp + sizeof (void *);
/* store user program stack pointer to the thread's
user_esp before changing to kernel mode */
struct thread *t = thread_current ();
t->user_esp = f->esp;
switch (syscall_num)
{
case SYS_HALT:
syscall_halt (f, cur_sp);
break;
case SYS_EXIT:
syscall_exit (f, cur_sp);
break;
case SYS_EXEC:
syscall_exec (f, cur_sp);
break;
case SYS_WAIT:
syscall_wait (f, cur_sp);
break;
case SYS_CREATE:
syscall_create (f, cur_sp);
break;
case SYS_REMOVE:
syscall_remove (f, cur_sp);
break;
case SYS_OPEN:
syscall_open (f, cur_sp);
break;
case SYS_FILESIZE:
syscall_filesize (f, cur_sp);
break;
case SYS_READ:
syscall_read (f, cur_sp);
break;
case SYS_WRITE:
syscall_write (f, cur_sp);
break;
case SYS_SEEK:
syscall_seek (f, cur_sp);
break;
case SYS_TELL:
syscall_tell (f, cur_sp);
break;
case SYS_CLOSE:
syscall_close (f, cur_sp);
break;
case SYS_MMAP:
syscall_mmap (f, cur_sp);
break;
case SYS_MUNMAP:
syscall_unmmap (f, cur_sp);
break;
default :
printf ("Invalid system call! #%d\n", syscall_num);
syscall_thread_exit (f, -1);
break;
}
}
static void
syscall_handler (struct intr_frame *f)
{
/* Validate the first addr of the stack frame */
void *esp = utok_addr (f->esp, NULL);
if (esp == NULL) {
syscall_exit (-1);
return;
}
enum SYSCALL_NUMBER call_number = *(enum SYSCALL_NUMBER *) esp;
if (call_number < syscall_first_call || call_number > syscall_last_call) {
syscall_exit (-1);
return;
}
/* Buffer the arguments for validation */
int argc = syscall_argc[call_number];
uint32_t argbuf[3];
int i = 0;
for (; i < argc; i++) {
/* Validate each argument */
void *vaddr = uptr_valid((uint32_t *) f->esp + 1 + i, f->esp);
if (vaddr == NULL) {
syscall_exit (-1);
return;
}
/* Translate the argument to kernel virtual (== physical) memory */
argbuf[i] = *(uint32_t *) vaddr;
}
int retval = 0;
/* Switch based on call_number to delegate to corresponding syscall.
Have not implemented several syscalls as of this project.
Use validation methods to check user-provided arguments.
*/
switch (call_number) {
case SYS_HALT:
syscall_halt ();
break;
case SYS_EXIT:
syscall_exit ((int) argbuf[0]);
break;
case SYS_EXEC:
if (str_valid ((void *) argbuf[0], f->esp) == NULL) {
syscall_exit (-1);
return;
}
retval = syscall_exec ((char *) argbuf[0]);
break;
case SYS_WAIT:
retval = syscall_wait ((int) argbuf[0]);
break;
case SYS_CREATE:
if (str_valid ((char *) argbuf[0], f->esp) == NULL) {
syscall_exit (-1);
return;
}
retval = (int) syscall_create ((char *) argbuf[0],
(unsigned) argbuf[1]);
break;
case SYS_REMOVE:
if (!uptr_valid ((char *) argbuf[0], f->esp)) {
syscall_exit (-1);
return;
}
retval = (int) syscall_remove ((char *) argbuf[0]);
break;
case SYS_OPEN:
if (str_valid ((char *) argbuf[0], f->esp) == NULL) {
syscall_exit (-1);
return;
}
retval = (int) syscall_open ((char *) argbuf[0]);
break;
case SYS_FILESIZE:
retval = syscall_filesize ((int) argbuf[0]);
break;
case SYS_READ:
if (buffer_valid ((void *) argbuf[1], f->esp,
(unsigned) argbuf[2]) == NULL) {
syscall_exit (-1);
return;
}
retval = syscall_read ((int) argbuf[0],
(void *) argbuf[1],
(unsigned) argbuf[2]);
break;
case SYS_WRITE:
if (buffer_valid ((void *) argbuf[1], f->esp,
(unsigned) argbuf[2]) == NULL) {
syscall_exit (-1);
return;
}
retval = syscall_write ((int) argbuf[0],
(void *) argbuf[1],
(unsigned) argbuf[2]);
break;
case SYS_SEEK:
syscall_seek ((int) argbuf[0], (unsigned) argbuf[1]);
break;
case SYS_TELL:
retval = (int) syscall_tell ((int) argbuf[0]);
break;
case SYS_CLOSE:
syscall_close ((int) argbuf[0]);
break;
#ifdef VM
case SYS_MMAP:
// addr will be checked internally inside mmap
retval = (int) syscall_mmap ((int) argbuf[0], (void *) argbuf[1]);
break;
case SYS_MUNMAP:
syscall_munmap ((int) argbuf[0]);
break;
#endif
default:
printf("unhandled system call!\n");
thread_exit();
}
f->eax = retval;
}
static void
syscall_handler (struct intr_frame *f)
{
int nsyscall, argc, i;
int *esp = (int *)f->esp; /* get argument pointer */
int *arg_int[3];
void **arg_ptr[3];
/* verify the argument pointer */
if (!IS_VALID(esp))
goto error_end;
/* system call number */
nsyscall = *(esp++);
/* number of arguments */
switch (nsyscall) {
case SYS_HALT:
argc = 0;
break;
case SYS_EXIT:
case SYS_EXEC:
case SYS_WAIT:
case SYS_TELL:
case SYS_CLOSE:
case SYS_REMOVE:
case SYS_OPEN:
case SYS_FILESIZE:
argc = 1;
break;
case SYS_CREATE:
case SYS_SEEK:
argc = 2;
break;
case SYS_READ:
case SYS_WRITE:
argc = 3;
break;
default:
goto error_end;
}
/* verify the argument pointer */
for (i = 0; i < argc; i++)
if (IS_VALID(esp + i)) {
arg_int[i] = esp + i;
arg_ptr[i] = (void**)(esp + i);
} else {
break;
}
if (i < argc)
goto error_end;
/* system call */
switch (nsyscall) {
case SYS_HALT:
shutdown_power_off();
break;
case SYS_EXIT:
syscall_exit(*arg_int[0]);
break;
case SYS_EXEC:
if (!IS_VALID(*arg_ptr[0]))
goto error_end;
lock_acquire (&lock_filesys);
f->eax = process_execute(*arg_ptr[0]);
lock_release (&lock_filesys);
break;
case SYS_WAIT:
f->eax = process_wait(*arg_int[0]);
break;
case SYS_TELL:
lock_acquire (&lock_filesys);
f->eax = syscall_tell(*arg_int[0]);
lock_release (&lock_filesys);
break;
case SYS_CLOSE:
lock_acquire (&lock_filesys);
process_file_close(*arg_int[0]);
lock_release (&lock_filesys);
break;
case SYS_REMOVE:
if (!IS_VALID(*arg_ptr[0]))
goto error_end;
lock_acquire (&lock_filesys);
f->eax = syscall_remove(*arg_ptr[0]);
lock_release (&lock_filesys);
break;
case SYS_OPEN:
if (!IS_VALID(*arg_ptr[0]))
goto error_end;
lock_acquire (&lock_filesys);
f->eax = process_file_open(*arg_ptr[0]);
lock_release (&lock_filesys);
break;
case SYS_FILESIZE:
lock_acquire (&lock_filesys);
f->eax = syscall_filesize(*arg_int[0]);
lock_release (&lock_filesys);
break;
case SYS_CREATE:
if (!IS_VALID(*arg_ptr[0]))
goto error_end;
lock_acquire (&lock_filesys);
f->eax = syscall_create(*arg_ptr[0], *arg_int[1]);
lock_release (&lock_filesys);
break;
case SYS_SEEK:
lock_acquire (&lock_filesys);
syscall_seek(*arg_int[0], *arg_int[1]);
lock_release (&lock_filesys);
break;
case SYS_READ:
if (!IS_VALID(*arg_ptr[1]))
goto error_end;
lock_acquire (&lock_filesys);
f->eax = syscall_read(*arg_int[0], *arg_ptr[1], *arg_int[2]);
lock_release (&lock_filesys);
break;
case SYS_WRITE:
if (!IS_VALID(*arg_ptr[1]))
goto error_end;
lock_acquire (&lock_filesys);
f->eax = syscall_write(*arg_int[0], *arg_ptr[1], *arg_int[2]);
lock_release (&lock_filesys);
break;
default:
printf ("Unknown syscall : %d\n", nsyscall);
goto error_end;
}
return;
error_end:
thread_exit ();
}
static void
syscall_handler (struct intr_frame *f)
{
// XXX : EDIT WITH 'syscall.h' 'lib/user/syscall.c' 'lib/syscall-nr.h
//printf ("system call!\n");
void *now = f->esp;
// XXX : Check PTR Range, and bash to syscall_exit(-1);
if(!is_valid_ptr(now))
syscall_exit(-1);
int syscall_number = *(int *)(f->esp);
int argc_size_table[22] = { // CHECK syscall-nr.h
0, // SYS_HALT (*) :0
1, // SYS_EXIT (*) :1
1, // SYS_EXEC (*) :2
1, // SYS_WAIT (*) :3
2, // SYS_CREATE :4
1, // SYS_REMOVE :5
1, // SYS_OPEN :6
1, // SYS_FILESIZE :7
3, // SYS_READ (*) :8
3, // SYS_WRITE (*):9
2, // SYS_SEEK :10
1, // SYS_TELL :11
1, // SYS_CLOSE :12 (proj 2-2)
2, // SYS_MMAP
1, // SYS_MUNMAP
1, // SYS_CHDIR
1, // SYS_MKDIR
2, // SYS_READDIR
1, // SYS_ISDIR
1, // SYS_INUMBER
1, // SYS_PIBONACCI
4 // SYS_SUM_OF_FOUR_INTEGERS
};
int argc_size = argc_size_table[syscall_number];
//printf("SYSCALL %d SIZE %d\n", syscall_number, argc_size);
void *argc[4] = {NULL,};
{
int i;
for(i = 0; i < argc_size; i++){
now += 4; // sizeof(void *); // IT WILL USE 4 Bytes. (ref:man38).
argc[i] = now;
// XXX : Check argument's ptr;
if(!is_valid_ptr(argc[i]))
syscall_exit(-1);
// printf("%x\n", now);
}
}
switch(syscall_number){
default:
case -1:
break;
case 0: // SYS_HALT
syscall_halt();
break;
case 1: // SYS_EXIT
syscall_exit(*(int *)argc[0]);
break;
case 2: // SYS_EXEC
f->eax = syscall_exec(*(const char **)argc[0]);
break;
case 3: // SYS_WAIT
//printf("CALLED SYS_WAIT!\n");
f->eax = syscall_wait(*(pid_t *)argc[0]);
break;
case 4: // SYS_CREATE
f->eax = syscall_create(*(const char **)argc[0],
*(unsigned *)argc[1]);
break;
case 5: // SYS_REMOVE
f->eax = syscall_remove(*(const char **)argc[0]);
break;
case 6: // SYS_OPEN
f->eax = syscall_open(*(const char **)argc[0]);
break;
case 7: // SYS_FILESIZE
f->eax = syscall_filesize(*(int *)argc[0]);
break;
case 8: // SYS_READ
f->eax = syscall_read(
*(int *)argc[0],
*(void **)argc[1],
*(unsigned *)argc[2]
);
break;
case 9: // SYS_WRITE
//printf("CALLED WRITE! %d %x %u\n", *(int *)argc[0], argc[1], *(unsigned *)argc[2]);
f->eax = syscall_write(
*(int *)argc[0],
*(const void **)argc[1],
*(unsigned *)argc[2]
);
break;
case 10: // SYS_SEEK
syscall_seek(*(int *)argc[0],
*(unsigned *)argc[1]
);
break;
case 11: // SYS_TELL
f->eax = syscall_tell(*(int *)argc[0]);
break;
case 12: // SYS_CLOSE
syscall_close(*(int *)argc[0]);
break;
case 20: // SYS_PIBONACCI
f->eax = syscall_pibonacci(*(int *)argc[0]);
break;
case 21: // SYS_SUM_OF_FOUR_INTEGERS
f->eax = syscall_sum_of_four_integers(
*(int *)argc[0],
*(int *)argc[1],
*(int *)argc[2],
*(int *)argc[3]
);
break;
// case *:
}
// printf("SYSCALL_RETURN: %d\n", f->eax);
// thread_exit ();
// XXX
}
/**
* Handle system calls. Interrupts are enabled when this function is
* called.
*
* @param user_context The userland context (CPU registers as they
* where when system call instruction was called in userland)
*/
void syscall_handle(context_t *user_context)
{
/* When a syscall is executed in userland, register a0 contains
* the number of the syscall. Registers a1, a2 and a3 contain the
* arguments of the syscall. The userland code expects that after
* returning from the syscall instruction the return value of the
* syscall is found in register v0. Before entering this function
* the userland context has been saved to user_context and after
* returning from this function the userland context will be
* restored from user_context.
*/
switch (A0) {
case SYSCALL_HALT:
halt_kernel();
break;
case SYSCALL_READ: {
int filehandle = (int)A1;
if (filehandle == FILEHANDLE_STDIN || filehandle == FILEHANDLE_STDOUT
|| filehandle == FILEHANDLE_STDERR) {
V0 = io_read((int) A1, (void*) A2, (int) A3);
} else {
V0 = syscall_read((openfile_t)A1, (void *)A2, (int)A3);
}
}
break;
case SYSCALL_WRITE: {
int filehandle = (int)A1;
if (filehandle == FILEHANDLE_STDIN || filehandle == FILEHANDLE_STDOUT
|| filehandle == FILEHANDLE_STDERR) {
V0 = io_write((int) A1, (void*) A2, (int) A3);
} else {
V0 = syscall_write((openfile_t)A1, (void *)A2, (int)A3);
}
}
break;
case SYSCALL_EXEC:
V0 = syscall_exec((char*) A1);
break;
case SYSCALL_EXIT:
syscall_exit((int) A1);
break;
case SYSCALL_JOIN:
V0 = syscall_join((process_id_t) A1);
break;
case SYSCALL_OPEN:
V0 = syscall_open((char *) A1);
break;
case SYSCALL_CLOSE:
V0 = syscall_close((openfile_t) A1);
break;
case SYSCALL_SEEK:
V0 = syscall_seek((openfile_t)A1, (int)A2);
break;
case SYSCALL_CREATE:
V0 = syscall_create((const char *)A1, (int)A2);
break;
case SYSCALL_REMOVE:
V0 = syscall_remove((const char *)A1);
break;
case SYSCALL_TELL:
V0 = syscall_tell((openfile_t)A1);
break;
case SYSCALL_SEM_OPEN:
V0 = (uint32_t) usr_sem_open((char*) A1, A2);
break;
case SYSCALL_SEM_PROCURE:
V0 = usr_sem_p((usr_sem_t*) A1);
break;
case SYSCALL_SEM_VACATE:
V0 = usr_sem_v((usr_sem_t*) A1);
break;
case SYSCALL_SEM_DESTROY:
V0 = usr_sem_destroy((usr_sem_t*) A1);
break;
default:
KERNEL_PANIC("Unhandled system call\n");
}
/* Move to next instruction after system call */
user_context->pc += 4;
}
