dubious change to not remove wired mappings in pmap_protect_page.

(can lead to mappings that cannot be removed as opposed to removing wired
mappings that shouldn't be removed)

SCCS-vsn: sys/hp300/hp300/pmap.c 8.4

diff --git a/usr/src/sys/hp300/hp300/pmap.c b/usr/src/sys/hp300/hp300/pmap.c
index faeb78e..004cf75 100644 (file)
--- a/usr/src/sys/hp300/hp300/pmap.c
+++ b/usr/src/sys/hp300/hp300/pmap.c
@@ -8,7 +8,7 @@
  *
  * %sccs.include.redist.c%
  *
  *
  * %sccs.include.redist.c%
  *

- *     @(#)pmap.c      8.3 (Berkeley) %G%
+ *     @(#)pmap.c      8.4 (Berkeley) %G%

  */
 
 /*
  */
 
 /*


@@ -770,29 +770,40 @@ pmap_page_protect(pa, prot)
        switch (prot) {
        case VM_PROT_READ|VM_PROT_WRITE:
        case VM_PROT_ALL:
        switch (prot) {
        case VM_PROT_READ|VM_PROT_WRITE:
        case VM_PROT_ALL:

-               break;
+               return;

        /* copy_on_write */
        case VM_PROT_READ:
        case VM_PROT_READ|VM_PROT_EXECUTE:
                pmap_changebit(pa, PG_RO, TRUE);
        /* copy_on_write */
        case VM_PROT_READ:
        case VM_PROT_READ|VM_PROT_EXECUTE:
                pmap_changebit(pa, PG_RO, TRUE);

-               break;
+               return;

        /* remove_all */
        default:
        /* remove_all */
        default:

-               pv = pa_to_pvh(pa);
-               s = splimp();
-               while (pv->pv_pmap != NULL) {
+               break;
+       }
+       pv = pa_to_pvh(pa);
+       s = splimp();
+       while (pv->pv_pmap != NULL) {
+               register pt_entry_t *pte;
+
+               pte = pmap_pte(pv->pv_pmap, pv->pv_va);

 #ifdef DEBUG
 #ifdef DEBUG

-                       if (!pmap_ste_v(pv->pv_pmap, pv->pv_va) ||
-                           pmap_pte_pa(pmap_pte(pv->pv_pmap,pv->pv_va)) != pa)
-                               panic("pmap_page_protect: bad mapping");
+               if (!pmap_ste_v(pv->pv_pmap, pv->pv_va) ||
+                   pmap_pte_pa(pte) != pa)
+                       panic("pmap_page_protect: bad mapping");

 #endif
 #endif

+               if (!pmap_pte_w(pte))

                        pmap_remove_mapping(pv->pv_pmap, pv->pv_va,
                        pmap_remove_mapping(pv->pv_pmap, pv->pv_va,

-                                           PT_ENTRY_NULL,
-                                           PRM_TFLUSH|PRM_CFLUSH);
+                                           pte, PRM_TFLUSH|PRM_CFLUSH);
+               else {
+                       pv = pv->pv_next;
+#ifdef DEBUG
+                       if (pmapdebug & PDB_PARANOIA)
+                               printf("%s wired mapping for %x not removed\n",
+                                      "pmap_page_protect:", pa);
+#endif

                }
                }

-               splx(s);
-               break;

        }
        }

+       splx(s);

 }
 
 /*
 }
 
 /*


@@ -1627,6 +1638,11 @@ pmap_pageable(pmap, sva, eva, pageable)
                 */
                pmap_changebit(pa, PG_M, FALSE);
 #ifdef DEBUG
                 */
                pmap_changebit(pa, PG_M, FALSE);
 #ifdef DEBUG

+               if ((PHYS_TO_VM_PAGE(pa)->flags & PG_CLEAN) == 0) {
+                       printf("pa %x: flags=%x: not clean\n",
+                              pa, PHYS_TO_VM_PAGE(pa)->flags);
+                       PHYS_TO_VM_PAGE(pa)->flags |= PG_CLEAN;
+               }

                if (pmapdebug & PDB_PTPAGE)
                        printf("pmap_pageable: PT page %x(%x) unmodified\n",
                               sva, *(int *)pmap_pte(pmap, sva));
                if (pmapdebug & PDB_PTPAGE)
                        printf("pmap_pageable: PT page %x(%x) unmodified\n",
                               sva, *(int *)pmap_pte(pmap, sva));


@@ -1986,6 +2002,10 @@ pmap_remove_mapping(pmap, va, pte, flags)
                                        PMAP_ACTIVATE(ptpmap,
                                            (struct pcb *)curproc->p_addr, 1);
                        }
                                        PMAP_ACTIVATE(ptpmap,
                                            (struct pcb *)curproc->p_addr, 1);
                        }

+#ifdef DEBUG
+                       else if (ptpmap->pm_sref < 0)
+                               panic("remove: sref < 0");
+#endif

                }
 #if 0
                /*
                }
 #if 0
                /*