static int do_op_one_page(unsigned long addr, int len, int is_write,
int (*op)(unsigned long addr, int len, void *arg), void *arg)
{
jmp_buf buf;
struct page *page;
pte_t *pte;
int n, faulted;
pte = maybe_map(addr, is_write);
if (pte == NULL)
return -1;
page = pte_page(*pte);
addr = (unsigned long) kmap_atomic(page, KM_UML_USERCOPY) +
(addr & ~PAGE_MASK);
current->thread.fault_catcher = &buf;
faulted = UML_SETJMP(&buf);
if (faulted == 0)
n = (*op)(addr, len, arg);
else
n = -1;
current->thread.fault_catcher = NULL;
kunmap_atomic(page, KM_UML_USERCOPY);
return n;
}
int run_kernel_thread(int (*fn)(void *), void *arg, jmp_buf **jmp_ptr)
{
jmp_buf buf;
int n;
*jmp_ptr = &buf;
n = UML_SETJMP(&buf);
if (n != 0)
return n;
(*fn)(arg);
return 0;
}
int setjmp_wrapper(void (*proc)(void *, void *), ...)
{
va_list args;
jmp_buf buf;
int n;
n = UML_SETJMP(&buf);
if(n == 0){
va_start(args, proc);
(*proc)(&buf, &args);
}
va_end(args);
return n;
}
int __do_strnlen_user(const char *str, unsigned long n,
void **fault_addr, void **fault_catcher)
{
struct tt_regs save = TASK_REGS(get_current())->tt;
int ret;
unsigned long *faddrp = (unsigned long *)fault_addr;
jmp_buf jbuf;
*fault_catcher = &jbuf;
if(UML_SETJMP(&jbuf) == 0)
ret = strlen(str) + 1;
else ret = *faddrp - (unsigned long) str;
*fault_addr = NULL;
*fault_catcher = NULL;
TASK_REGS(get_current())->tt = save;
return ret;
}
unsigned long __do_user_copy(void *to, const void *from, int n,
void **fault_addr, jmp_buf **fault_catcher,
void (*op)(void *to, const void *from,
int n), int *faulted_out)
{
unsigned long *faddrp = (unsigned long *) fault_addr, ret;
jmp_buf jbuf;
*fault_catcher = &jbuf;
if (UML_SETJMP(&jbuf) == 0) {
(*op)(to, from, n);
ret = 0;
*faulted_out = 0;
}
else {
ret = *faddrp;
*faulted_out = 1;
}
*fault_addr = NULL;
*fault_catcher = NULL;
return ret;
}