Commit 5db06565 authored by Heiko Carstens's avatar Heiko Carstens Committed by Vasily Gorbik
Browse files

s390/mm,fault: get rid of do_low_address() 



There is only one caller of do_low_address(). Given that this code is
quite special just get rid of do_low_address, and add it to
do_protection_exception() in order to make the code a bit more
readable.

Signed-off-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent cca12b42

arch/s390/mm/fault.c

+9 −16
Original line number Diff line number Diff line
@@ -257,20 +257,6 @@ static void do_no_context(struct pt_regs *regs, vm_fault_t fault) 
	die(regs, "Oops");

}



static void do_low_address(struct pt_regs *regs)

{

	/*

	 * Low-address protection hit in kernel mode means

	 * NULL pointer write access in kernel mode.

	 */

	if (regs->psw.mask & PSW_MASK_PSTATE) {

		/* Low-address protection hit in user mode: 'cannot happen' */

		die(regs, "Low-address protection");

	}



	do_no_context(regs, VM_FAULT_BADACCESS);

}



static void do_sigbus(struct pt_regs *regs)

{

	force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)get_fault_address(regs));
@@ -504,8 +490,15 @@ void do_protection_exception(struct pt_regs *regs) 
	 * field is not guaranteed to contain valid data in this case.

	 */

	if (unlikely(!teid.b61)) {

		do_low_address(regs);

		return;

		if (user_mode(regs)) {

			/* Low-address protection in user mode: cannot happen */

			die(regs, "Low-address protection");

		}

		/*

		 * Low-address protection in kernel mode means

		 * NULL pointer write access in kernel mode.

		 */

		return do_no_context(regs, VM_FAULT_BADACCESS);

	}

	if (unlikely(MACHINE_HAS_NX && teid.b56)) {

		regs->int_parm_long = (teid.addr * PAGE_SIZE) | (regs->psw.addr & PAGE_MASK);