s390/mm,fault: remove VM_FAULT_BADCONTEXT

Remove VM_FAULT_BADCONTEXT and instead call do_no_context() via
wrappers. This adds two new wrappers similar to what x86 has:

handle_fault_error() and handle_fault_error_nolock(). Both of them
simply call do_no_context(), while handle_fault_error() also unlocks
mmap lock, which avoids adding lots of mmap_read_unlock() calls with
this and subsequent patches.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index e0dbc231828c8f55d6acec425823eb18be54520a..05c908051e93b870a9cd418b02fe4e4a5f46fa94 100644 (file)
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -49,7 +49,6 @@
  * Allocate private vm_fault_reason from top.
  * Please make sure it won't collide with vm_fault_reason.
  */
-#define VM_FAULT_BADCONTEXT    ((__force vm_fault_t)0x80000000)
 #define VM_FAULT_BADMAP                ((__force vm_fault_t)0x40000000)
 #define VM_FAULT_BADACCESS     ((__force vm_fault_t)0x20000000)
 #define VM_FAULT_SIGNAL                ((__force vm_fault_t)0x10000000)
@@ -257,6 +256,19 @@ static void do_no_context(struct pt_regs *regs)
        die(regs, "Oops");
 }
 
+static inline void handle_fault_error_nolock(struct pt_regs *regs)
+{
+       do_no_context(regs);
+}
+
+static void handle_fault_error(struct pt_regs *regs)
+{
+       struct mm_struct *mm = current->mm;
+
+       mmap_read_unlock(mm);
+       handle_fault_error_nolock(regs);
+}
+
 static void do_sigbus(struct pt_regs *regs)
 {
        force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)get_fault_address(regs));
@@ -277,8 +289,6 @@ static void do_fault_error(struct pt_regs *regs, vm_fault_t fault)
                        do_sigsegv(regs, si_code);
                        break;
                }
-               fallthrough;
-       case VM_FAULT_BADCONTEXT:
                do_no_context(regs);
                break;
        case VM_FAULT_SIGNAL:
@@ -344,15 +354,14 @@ static void do_exception(struct pt_regs *regs, int access)
        mm = tsk->mm;
        address = get_fault_address(regs);
        is_write = fault_is_write(regs);
-       fault = VM_FAULT_BADCONTEXT;
        type = get_fault_type(regs);
        switch (type) {
        case KERNEL_FAULT:
-               goto out;
+               return handle_fault_error_nolock(regs);
        case USER_FAULT:
        case GMAP_FAULT:
                if (faulthandler_disabled() || !mm)
-                       goto out;
+                       return handle_fault_error_nolock(regs);
                break;
        }
        perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
@@ -443,8 +452,7 @@ retry:
                         * mmap_lock has not been released
                         */
                        current->thread.gmap_pfault = 1;
-                       fault = VM_FAULT_BADCONTEXT;
-                       goto out_up;
+                       return handle_fault_error(regs);
                }
                flags &= ~FAULT_FLAG_RETRY_NOWAIT;
                flags |= FAULT_FLAG_TRIED;