int
ia32_clone_tls (struct task_struct *child, struct pt_regs *childregs)
{
struct desc_struct *desc;
struct ia32_user_desc info;
int idx;
if (copy_from_user(&info, (void __user *)(childregs->r14 & 0xffffffff), sizeof(info)))
return -EFAULT;
if (LDT_empty(&info))
return -EINVAL;
idx = info.entry_number;
if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
return -EINVAL;
desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
desc->a = LDT_entry_a(&info);
desc->b = LDT_entry_b(&info);
/* XXX: can this be done in a cleaner way ? */
load_TLS(&child->thread, smp_processor_id());
ia32_load_segment_descriptors(child);
load_TLS(¤t->thread, smp_processor_id());
return 0;
}
int set_tls_array(struct thread_struct *t, int idx, unsigned long addr, unsigned int limit)
{
struct user_desc info;
struct desc_struct *desc;
if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
return -EINVAL;
desc = t->tls_array + idx - GDT_ENTRY_TLS_MIN;
info.entry_number = idx;
info.base_addr = addr;
info.limit = limit;
info.contents = 0;
info.read_exec_only = 0;
info.seg_not_present = 0;
info.seg_32bit = 1;
info.limit_in_pages = 1;
info.useable = 0;
/* FIXME */
fill_ldt(desc, &info);
#if 0
desc->a = LDT_entry_a(&info);
desc->b = LDT_entry_b(&info);
#endif
return 0;
}
/*
* Set a given TLS descriptor:
* When you want addresses > 32bit use arch_prctl()
*/
int do_set_thread_area(struct thread_struct *t, struct user_desc __user *u_info)
{
struct user_desc info;
struct n_desc_struct *desc;
int cpu, idx;
if (copy_from_user(&info, u_info, sizeof(info)))
return -EFAULT;
idx = info.entry_number;
/*
* index -1 means the kernel should try to find and
* allocate an empty descriptor:
*/
if (idx == -1) {
idx = get_free_idx();
if (idx < 0)
return idx;
if (put_user(idx, &u_info->entry_number))
return -EFAULT;
}
if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
return -EINVAL;
desc = ((struct n_desc_struct *)t->tls_array) + idx - GDT_ENTRY_TLS_MIN;
/*
* We must not get preempted while modifying the TLS.
*/
cpu = get_cpu();
if (LDT_empty(&info)) {
desc->a = 0;
desc->b = 0;
} else {
desc->a = LDT_entry_a(&info);
desc->b = LDT_entry_b(&info);
}
if (t == ¤t->thread)
load_TLS(t, cpu);
put_cpu();
return 0;
}
int ia32_child_tls(struct task_struct *p, struct pt_regs *childregs)
{
struct n_desc_struct *desc;
struct user_desc info, *cp;
int idx;
cp = (void *)childregs->rsi;
if (copy_from_user(&info, cp, sizeof(info)))
return -EFAULT;
if (LDT_empty(&info))
return -EINVAL;
idx = info.entry_number;
if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
return -EINVAL;
desc = (struct n_desc_struct *)(p->thread.tls_array) + idx - GDT_ENTRY_TLS_MIN;
desc->a = LDT_entry_a(&info);
desc->b = LDT_entry_b(&info);
return 0;
}
int copy_thread(int nr, unsigned long clone_flags, unsigned long esp,
unsigned long unused,
struct task_struct * p, struct pt_regs * regs)
{
struct pt_regs * childregs;
struct task_struct *tsk;
int err;
childregs = task_pt_regs(p);
*childregs = *regs;
childregs->eax = 0;
childregs->esp = esp;
p->thread.esp = (unsigned long) childregs;
p->thread.esp0 = (unsigned long) (childregs+1);
p->thread.eip = (unsigned long) ret_from_fork;
savesegment(fs,p->thread.fs);
savesegment(gs,p->thread.gs);
tsk = current;
if (unlikely(test_tsk_thread_flag(tsk, TIF_IO_BITMAP))) {
p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);
if (!p->thread.io_bitmap_ptr) {
p->thread.io_bitmap_max = 0;
return -ENOMEM;
}
memcpy(p->thread.io_bitmap_ptr, tsk->thread.io_bitmap_ptr,
IO_BITMAP_BYTES);
set_tsk_thread_flag(p, TIF_IO_BITMAP);
}
/*
* Set a new TLS for the child thread?
*/
if (clone_flags & CLONE_SETTLS) {
struct desc_struct *desc;
struct user_desc info;
int idx;
err = -EFAULT;
if (copy_from_user(&info, (void __user *)childregs->esi, sizeof(info)))
goto out;
err = -EINVAL;
if (LDT_empty(&info))
goto out;
idx = info.entry_number;
if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
goto out;
desc = p->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
desc->a = LDT_entry_a(&info);
desc->b = LDT_entry_b(&info);
}
p->thread.iopl = current->thread.iopl;
err = 0;
out:
if (err && p->thread.io_bitmap_ptr) {
kfree(p->thread.io_bitmap_ptr);
p->thread.io_bitmap_max = 0;
}
return err;
}
int copy_thread(int nr, unsigned long clone_flags, unsigned long esp,
unsigned long unused,
struct task_struct * p, struct pt_regs * regs)
{
struct pt_regs * childregs;
struct task_struct *tsk;
int err, i;
childregs = ((struct pt_regs *) (THREAD_SIZE + (unsigned long) p->thread_info)) - 1;
*childregs = *regs;
childregs->eax = 0;
childregs->esp = esp;
p->set_child_tid = p->clear_child_tid = NULL;
p->thread.esp = (unsigned long) childregs;
p->thread.esp0 = (unsigned long) (childregs+1);
/*
* get the two stack pages, for the virtual stack.
*
* IMPORTANT: this code relies on the fact that the task
* structure is an THREAD_SIZE aligned piece of physical memory.
*/
for (i = 0; i < ARRAY_SIZE(p->thread.stack_page); i++)
p->thread.stack_page[i] =
virt_to_page((unsigned long)p->thread_info + (i*PAGE_SIZE));
p->thread.eip = (unsigned long) ret_from_fork;
p->thread_info->real_stack = p->thread_info;
savesegment(fs,p->thread.fs);
savesegment(gs,p->thread.gs);
tsk = current;
if (unlikely(NULL != tsk->thread.io_bitmap_ptr)) {
p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);
if (!p->thread.io_bitmap_ptr) {
p->thread.io_bitmap_max = 0;
return -ENOMEM;
}
memcpy(p->thread.io_bitmap_ptr, tsk->thread.io_bitmap_ptr,
IO_BITMAP_BYTES);
}
/*
* Set a new TLS for the child thread?
*/
if (clone_flags & CLONE_SETTLS) {
struct desc_struct *desc;
struct user_desc info;
int idx;
err = -EFAULT;
if (copy_from_user(&info, (void __user *)childregs->esi, sizeof(info)))
goto out;
err = -EINVAL;
if (LDT_empty(&info))
goto out;
idx = info.entry_number;
if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
goto out;
desc = p->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
desc->a = LDT_entry_a(&info);
desc->b = LDT_entry_b(&info);
}
p->thread.io_pl = current->thread.io_pl;
err = 0;
out:
if (err && p->thread.io_bitmap_ptr) {
kfree(p->thread.io_bitmap_ptr);
p->thread.io_bitmap_max = 0;
}
return err;
}
