x86/uaccess: Move thread_info::uaccess_err and thread_info::sig_on_uaccess_err to thread_struct

struct thread_info is a legacy mess.  To prepare for its partial removal,
move the uaccess control fields out -- they're straightforward.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/d0ac4d01c8e4d4d756264604e47445d5acc7900e.1468527351.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c
index 4bb53b8..0f90cc2 100644
--- a/arch/x86/mm/extable.c
+++ b/arch/x86/mm/extable.c
@@ -37,7 +37,7 @@
 		   struct pt_regs *regs, int trapnr)
 {
 	/* Special hack for uaccess_err */
-	current_thread_info()->uaccess_err = 1;
+	current->thread.uaccess_err = 1;
 	regs->ip = ex_fixup_addr(fixup);
 	return true;
 }
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index ca44e2e..69be03d 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -737,7 +737,7 @@
 		 * In this case we need to make sure we're not recursively
 		 * faulting through the emulate_vsyscall() logic.
 		 */
-		if (current_thread_info()->sig_on_uaccess_error && signal) {
+		if (current->thread.sig_on_uaccess_error && signal) {
 			tsk->thread.trap_nr = X86_TRAP_PF;
 			tsk->thread.error_code = error_code | PF_USER;
 			tsk->thread.cr2 = address;