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>
This commit is contained in:
David Hildenbrand 2016-05-09 11:15:32 +02:00 committed by Christian Borntraeger
parent d3ed1ceeac
commit 8d6037a7b4

View File

@ -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;