[S390] Use do_exception() in pagetable walk usercopy functions.

The pagetable walk usercopy functions have used a modified copy of the
do_exception() function for fault handling. This lead to inconsistencies
with recent changes to do_exception(), e.g. performance counters. This
patch changes the pagetable walk usercopy code to call do_exception()
directly, eliminating the redundancy. A new parameter is added to
do_exception() to specify the fault address.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 5a9e9a77dc16..fc102e70d9c2 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -442,6 +442,29 @@ no_context:
 }
 #endif
 
+int __handle_fault(unsigned long uaddr, unsigned long int_code, int write_user)
+{
+	struct pt_regs regs;
+	int access, fault;
+
+	regs.psw.mask = psw_kernel_bits;
+	if (!irqs_disabled())
+		regs.psw.mask |= PSW_MASK_IO | PSW_MASK_EXT;
+	regs.psw.addr = (unsigned long) __builtin_return_address(0);
+	regs.psw.addr |= PSW_ADDR_AMODE;
+	uaddr &= PAGE_MASK;
+	access = write_user ? VM_WRITE : VM_READ;
+	fault = do_exception(&regs, access, uaddr | 2);
+	if (unlikely(fault)) {
+		if (fault & VM_FAULT_OOM) {
+			pagefault_out_of_memory();
+			fault = 0;
+		} else if (fault & VM_FAULT_SIGBUS)
+			do_sigbus(&regs, int_code, uaddr);
+	}
+	return fault ? -EFAULT : 0;
+}
+
 #ifdef CONFIG_PFAULT 
 /*
  * 'pfault' pseudo page faults routines.