Changeset 1dbc43f in mainline for kernel/arch/ppc32/src/mm/pht.c

Timestamp:

2012-11-22T21:23:47Z (11 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

908bb96

Parents:

34ae0a5

Message:

Unify user page fault handling in as_page_fault().

• Remove lots of architecture-dependent boilerplate code.

File:

• kernel/arch/ppc32/src/mm/pht.c (modified) (4 diffs)

kernel/arch/ppc32/src/mm/pht.c

@@ -49 +49 @@
  * @param access   Access mode that caused the fault.
  * @param istate   Pointer to interrupted state.
- * @param pfrc     Pointer to variable where as_page_fault() return code
- *                 will be stored.
  *
  * @return PTE on success, NULL otherwise.
@@ -56 +54 @@
  */
 static pte_t *find_mapping_and_check(as_t *as, uintptr_t badvaddr, int access,
-    istate_t *istate, int *pfrc)
+    istate_t *istate)
 {
         /*
@@ -68 +66 @@
                  */
                 return pte;
-        } else {
+        }
+        /*
+         * Mapping not found in page tables.
+         * Resort to higher-level page fault handler.
+         */
+        if (as_page_fault(badvaddr, access, istate) == AS_PF_OK) {
                 /*
-                 * Mapping not found in page tables.
-                 * Resort to higher-level page fault handler.
+                 * The higher-level page fault handler succeeded,
+                 * The mapping ought to be in place.
                  */
-                int rc = as_page_fault(badvaddr, access, istate);
-                switch (rc) {
-                case AS_PF_OK:
-                        /*
-                         * The higher-level page fault handler succeeded,
-                         * The mapping ought to be in place.
-                         */
-                        pte = page_mapping_find(as, badvaddr, true);
-                        ASSERT((pte) && (pte->present));
-                        *pfrc = 0;
-                        return pte;
-                case AS_PF_DEFER:
-                        *pfrc = rc;
-                        return NULL;
-                case AS_PF_FAULT:
-                        *pfrc = rc;
-                        return NULL;
-                default:
-                        panic("Unexpected rc (%d).", rc);
-                }
-        }
-}
-
-static void pht_refill_fail(uintptr_t badvaddr, istate_t *istate)
-{
-        fault_if_from_uspace(istate, "PHT Refill Exception on %p.",
-            (void *) badvaddr);
-        panic_memtrap(istate, PF_ACCESS_UNKNOWN, badvaddr,
-            "PHT Refill Exception.");
+                pte = page_mapping_find(as, badvaddr, true);
+                ASSERT((pte) && (pte->present));
+                return pte;
+        }
+
+        return NULL;
 }
 
@@ -202 +182 @@
                 badvaddr = istate->pc;
         
-        int pfrc;
         pte_t *pte = find_mapping_and_check(AS, badvaddr,
-            PF_ACCESS_READ /* FIXME */, istate, &pfrc);
-        
-        if (!pte) {
-                switch (pfrc) {
-                case AS_PF_FAULT:
-                        pht_refill_fail(badvaddr, istate);
-                        return;
-                case AS_PF_DEFER:
-                        /*
-                         * The page fault came during copy_from_uspace()
-                         * or copy_to_uspace().
-                         */
-                        return;
-                default:
-                        panic("Unexpected pfrc (%d).", pfrc);
-                }
-        }
-        
-        /* Record access to PTE */
-        pte->accessed = 1;
-        pht_insert(badvaddr, pte);
+            PF_ACCESS_READ /* FIXME */, istate);
+        
+        if (pte) {
+                /* Record access to PTE */
+                pte->accessed = 1;
+                pht_insert(badvaddr, pte);
+        }
 }