s390/mm: simplify get_guest_storage_key

We can safe a few LOC and make that function easier to understand
by rewriting existing code.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index 7612a7c..4c8d572 100644 (file)
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -551,20 +551,11 @@ unsigned long get_guest_storage_key(struct mm_struct *mm, unsigned long addr)
                return -EFAULT;
 
        pgste = pgste_get_lock(ptep);
-       if (pte_val(*ptep) & _PAGE_INVALID) {
-               key  = (pgste_val(pgste) & PGSTE_ACC_BITS) >> 56;
-               key |= (pgste_val(pgste) & PGSTE_FP_BIT) >> 56;
-               key |= (pgste_val(pgste) & PGSTE_GR_BIT) >> 48;
-               key |= (pgste_val(pgste) & PGSTE_GC_BIT) >> 48;
-       } else {
+       key = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56;
+       if (!(pte_val(*ptep) & _PAGE_INVALID))
                key = page_get_storage_key(pte_val(*ptep) & PAGE_MASK);
-
-               /* Reflect guest's logical view, not physical */
-               if (pgste_val(pgste) & PGSTE_GR_BIT)
-                       key |= _PAGE_REFERENCED;
-               if (pgste_val(pgste) & PGSTE_GC_BIT)
-                       key |= _PAGE_CHANGED;
-       }
+       /* Reflect guest's logical view, not physical */
+       key |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48;
        pgste_set_unlock(ptep, pgste);
        pte_unmap_unlock(ptep, ptl);
        return key;