s390: gmap use pte_unmap_unlock() not spin_unlock()

pte_alloc_map_lock() expects to be followed by pte_unmap_unlock(): to
keep balance in future, pass ptep as well as ptl to gmap_pte_op_end(),
and use pte_unmap_unlock() instead of direct spin_unlock() (even though
ptep ends up unused inside the macro).

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Hugh Dickins <[e-mail]>
Acked-by: Alexander Gordeev <[e-mail]>
Cc: Alexandre Ghiti <[e-mail]>
Cc: Aneesh Kumar K.V <[e-mail]>
Cc: Catalin Marinas <[e-mail]>
Cc: Christian Borntraeger <[e-mail]>
Cc: Chris Zankel <[e-mail]>
Cc: Claudio Imbrenda <[e-mail]>
Cc: David Hildenbrand <[e-mail]>
Cc: "David S. Miller" <[e-mail]>
Cc: Geert Uytterhoeven <[e-mail]>
Cc: Greg Ungerer <[e-mail]>
Cc: Heiko Carstens <[e-mail]>
Cc: Helge Deller <[e-mail]>
Cc: "H. Peter Anvin" <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: John David Anglin <[e-mail]>
Cc: John Paul Adrian Glaubitz <[e-mail]>
Cc: Kirill A. Shutemov <[e-mail]>
Cc: Matthew Wilcox (Oracle) <[e-mail]>
Cc: Max Filippov <[e-mail]>
Cc: Michael Ellerman <[e-mail]>
Cc: Michal Simek <[e-mail]>
Cc: Mike Kravetz <[e-mail]>
Cc: Mike Rapoport (IBM) <[e-mail]>
Cc: Palmer Dabbelt <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Qi Zheng <[e-mail]>
Cc: Russell King <[e-mail]>
Cc: Suren Baghdasaryan <[e-mail]>
Cc: Thomas Bogendoerfer <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: Will Deacon <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

arch/s390/mm/gmap.c

···
 
 /**
  * gmap_pte_op_end - release the page table lock
- * @ptl: pointer to the spinlock pointer
+ * @ptep: pointer to the locked pte
+ * @ptl: pointer to the page table spinlock
  */
-static void gmap_pte_op_end(spinlock_t *ptl)
+static void gmap_pte_op_end(pte_t *ptep, spinlock_t *ptl)
 {
-	if (ptl)
-		spin_unlock(ptl);
+	pte_unmap_unlock(ptep, ptl);
 }
 
 /**
···
 {
 	int rc;
 	pte_t *ptep;
-	spinlock_t *ptl = NULL;
+	spinlock_t *ptl;
 	unsigned long pbits = 0;
 
 	if (pmd_val(*pmdp) & _SEGMENT_ENTRY_INVALID)
···
 	pbits |= (bits & GMAP_NOTIFY_SHADOW) ? PGSTE_VSIE_BIT : 0;
 	/* Protect and unlock. */
 	rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot, pbits);
-	gmap_pte_op_end(ptl);
+	gmap_pte_op_end(ptep, ptl);
 	return rc;
 }
 
···
 				/* Do *NOT* clear the _PAGE_INVALID bit! */
 				rc = 0;
 			}
-			gmap_pte_op_end(ptl);
+			gmap_pte_op_end(ptep, ptl);
 		}
 		if (!rc)
 			break;
···
 			if (!rc)
 				gmap_insert_rmap(sg, vmaddr, rmap);
 			spin_unlock(&sg->guest_table_lock);
-			gmap_pte_op_end(ptl);
+			gmap_pte_op_end(ptep, ptl);
 		}
 		radix_tree_preload_end();
 		if (rc) {
···
 			tptep = (pte_t *) gmap_table_walk(sg, saddr, 0);
 			if (!tptep) {
 				spin_unlock(&sg->guest_table_lock);
-				gmap_pte_op_end(ptl);
+				gmap_pte_op_end(sptep, ptl);
 				radix_tree_preload_end();
 				break;
 			}
···
 				rmap = NULL;
 				rc = 0;
 			}
-			gmap_pte_op_end(ptl);
+			gmap_pte_op_end(sptep, ptl);
 			spin_unlock(&sg->guest_table_lock);
 		}
 		radix_tree_preload_end();
···
 				continue;
 			if (ptep_test_and_clear_uc(gmap->mm, vmaddr, ptep))
 				set_bit(i, bitmap);
-			spin_unlock(ptl);
+			pte_unmap_unlock(ptep, ptl);
 		}
 	}
 	gmap_pmd_op_end(gmap, pmdp);