x86/process: Unify copy_thread_tls()

While looking at the TSS io bitmap it turned out that any change in that
area would require identical changes to copy_thread_tls(). The 32 and 64
bit variants share sufficient code to consolidate them into a common
function to avoid duplication of upcoming modifications.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andy Lutomirski <luto@kernel.org>

1 files changed, 0 insertions, 75 deletions

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index af64519b2695..e93a1b8fd7f9 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -371,81 +371,6 @@ void x86_gsbase_write_task(struct task_struct *task, unsigned long gsbase)
 	task->thread.gsbase = gsbase;
 }
 
-int copy_thread_tls(unsigned long clone_flags, unsigned long sp,
-		unsigned long arg, struct task_struct *p, unsigned long tls)
-{
-	int err;
-	struct pt_regs *childregs;
-	struct fork_frame *fork_frame;
-	struct inactive_task_frame *frame;
-	struct task_struct *me = current;
-
-	childregs = task_pt_regs(p);
-	fork_frame = container_of(childregs, struct fork_frame, regs);
-	frame = &fork_frame->frame;
-
-	frame->bp = 0;
-	frame->ret_addr = (unsigned long) ret_from_fork;
-	p->thread.sp = (unsigned long) fork_frame;
-	p->thread.io_bitmap_ptr = NULL;
-
-	savesegment(gs, p->thread.gsindex);
-	p->thread.gsbase = p->thread.gsindex ? 0 : me->thread.gsbase;
-	savesegment(fs, p->thread.fsindex);
-	p->thread.fsbase = p->thread.fsindex ? 0 : me->thread.fsbase;
-	savesegment(es, p->thread.es);
-	savesegment(ds, p->thread.ds);
-	memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
-
-	if (unlikely(p->flags & PF_KTHREAD)) {
-		/* kernel thread */
-		memset(childregs, 0, sizeof(struct pt_regs));
-		frame->bx = sp;		/* function */
-		frame->r12 = arg;
-		return 0;
-	}
-	frame->bx = 0;
-	*childregs = *current_pt_regs();
-
-	childregs->ax = 0;
-	if (sp)
-		childregs->sp = sp;
-
-	err = -ENOMEM;
-	if (unlikely(test_tsk_thread_flag(me, TIF_IO_BITMAP))) {
-		p->thread.io_bitmap_ptr = kmemdup(me->thread.io_bitmap_ptr,
-						  IO_BITMAP_BYTES, GFP_KERNEL);
-		if (!p->thread.io_bitmap_ptr) {
-			p->thread.io_bitmap_max = 0;
-			return -ENOMEM;
-		}
-		set_tsk_thread_flag(p, TIF_IO_BITMAP);
-	}
-
-	/*
-	 * Set a new TLS for the child thread?
-	 */
-	if (clone_flags & CLONE_SETTLS) {
-#ifdef CONFIG_IA32_EMULATION
-		if (in_ia32_syscall())
-			err = do_set_thread_area(p, -1,
-				(struct user_desc __user *)tls, 0);
-		else
-#endif
-			err = do_arch_prctl_64(p, ARCH_SET_FS, tls);
-		if (err)
-			goto out;
-	}
-	err = 0;
-out:
-	if (err && p->thread.io_bitmap_ptr) {
-		kfree(p->thread.io_bitmap_ptr);
-		p->thread.io_bitmap_max = 0;
-	}
-
-	return err;
-}
-
 static void
 start_thread_common(struct pt_regs *regs, unsigned long new_ip,
 		    unsigned long new_sp,