Changes in kernel/genarch/src/mm/page_pt.c [d99c1d2:fdaad75d] in mainline

File:

• kernel/genarch/src/mm/page_pt.c (modified) (7 diffs)

kernel/genarch/src/mm/page_pt.c

@@ -33 +33 @@
 /**
  * @file
- * @brief       Virtual Address Translation for hierarchical 4-level page tables.
+ * @brief Virtual Address Translation for hierarchical 4-level page tables.
  */
 
@@ -46 +46 @@
 #include <memstr.h>
 
-static void pt_mapping_insert(as_t *as, uintptr_t page, uintptr_t frame, int flags);
-static void pt_mapping_remove(as_t *as, uintptr_t page);
-static pte_t *pt_mapping_find(as_t *as, uintptr_t page);
+static void pt_mapping_insert(as_t *, uintptr_t, uintptr_t, unsigned int);
+static void pt_mapping_remove(as_t *, uintptr_t);
+static pte_t *pt_mapping_find(as_t *, uintptr_t);
 
 page_mapping_operations_t pt_mapping_operations = {
@@ -61 +61 @@
  * using flags.
  *
- * The page table must be locked and interrupts must be disabled.
- *
- * @param as Address space to wich page belongs.
- * @param page Virtual address of the page to be mapped.
+ * @param as    Address space to wich page belongs.
+ * @param page  Virtual address of the page to be mapped.
  * @param frame Physical address of memory frame to which the mapping is done.
  * @param flags Flags to be used for mapping.
- */
-void pt_mapping_insert(as_t *as, uintptr_t page, uintptr_t frame, int flags)
+ *
+ */
+void pt_mapping_insert(as_t *as, uintptr_t page, uintptr_t frame,
+    unsigned int flags)
 {
-        pte_t *ptl0, *ptl1, *ptl2, *ptl3;
-        pte_t *newpt;
-
-        ptl0 = (pte_t *) PA2KA((uintptr_t) as->genarch.page_table);
-
+        pte_t *ptl0 = (pte_t *) PA2KA((uintptr_t) as->genarch.page_table);
+
+        ASSERT(page_table_locked(as));
+        
         if (GET_PTL1_FLAGS(ptl0, PTL0_INDEX(page)) & PAGE_NOT_PRESENT) {
-                newpt = (pte_t *)frame_alloc(PTL1_SIZE, FRAME_KA);
+                pte_t *newpt = (pte_t *) frame_alloc(PTL1_SIZE, FRAME_KA);
                 memsetb(newpt, FRAME_SIZE << PTL1_SIZE, 0);
                 SET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page), KA2PA(newpt));
                 SET_PTL1_FLAGS(ptl0, PTL0_INDEX(page), PAGE_PRESENT | PAGE_USER | PAGE_EXEC | PAGE_CACHEABLE | PAGE_WRITE);
         }
-
-        ptl1 = (pte_t *) PA2KA(GET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page)));
-
+        
+        pte_t *ptl1 = (pte_t *) PA2KA(GET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page)));
+        
         if (GET_PTL2_FLAGS(ptl1, PTL1_INDEX(page)) & PAGE_NOT_PRESENT) {
-                newpt = (pte_t *)frame_alloc(PTL2_SIZE, FRAME_KA);
+                pte_t *newpt = (pte_t *) frame_alloc(PTL2_SIZE, FRAME_KA);
                 memsetb(newpt, FRAME_SIZE << PTL2_SIZE, 0);
                 SET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page), KA2PA(newpt));
                 SET_PTL2_FLAGS(ptl1, PTL1_INDEX(page), PAGE_PRESENT | PAGE_USER | PAGE_EXEC | PAGE_CACHEABLE | PAGE_WRITE);
         }
-
-        ptl2 = (pte_t *) PA2KA(GET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page)));
-
+        
+        pte_t *ptl2 = (pte_t *) PA2KA(GET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page)));
+        
         if (GET_PTL3_FLAGS(ptl2, PTL2_INDEX(page)) & PAGE_NOT_PRESENT) {
-                newpt = (pte_t *)frame_alloc(PTL3_SIZE, FRAME_KA);
+                pte_t *newpt = (pte_t *) frame_alloc(PTL3_SIZE, FRAME_KA);
                 memsetb(newpt, FRAME_SIZE << PTL3_SIZE, 0);
                 SET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page), KA2PA(newpt));
                 SET_PTL3_FLAGS(ptl2, PTL2_INDEX(page), PAGE_PRESENT | PAGE_USER | PAGE_EXEC | PAGE_CACHEABLE | PAGE_WRITE);
         }
-
-        ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));
-
+        
+        pte_t *ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));
+        
         SET_FRAME_ADDRESS(ptl3, PTL3_INDEX(page), frame);
         SET_FRAME_FLAGS(ptl3, PTL3_INDEX(page), flags);
@@ -114 +113 @@
  * Empty page tables except PTL0 are freed.
  *
- * The page table must be locked and interrupts must be disabled.
- *
- * @param as Address space to wich page belongs.
+ * @param as   Address space to wich page belongs.
  * @param page Virtual address of the page to be demapped.
+ *
  */
 void pt_mapping_remove(as_t *as, uintptr_t page)
 {
-        pte_t *ptl0, *ptl1, *ptl2, *ptl3;
-        bool empty = true;
-        int i;
+        ASSERT(page_table_locked(as));
 
         /*
          * First, remove the mapping, if it exists.
+         *
          */
-
-        ptl0 = (pte_t *) PA2KA((uintptr_t) as->genarch.page_table);
-
+        
+        pte_t *ptl0 = (pte_t *) PA2KA((uintptr_t) as->genarch.page_table);
         if (GET_PTL1_FLAGS(ptl0, PTL0_INDEX(page)) & PAGE_NOT_PRESENT)
                 return;
-
-        ptl1 = (pte_t *) PA2KA(GET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page)));
-
+        
+        pte_t *ptl1 = (pte_t *) PA2KA(GET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page)));
         if (GET_PTL2_FLAGS(ptl1, PTL1_INDEX(page)) & PAGE_NOT_PRESENT)
                 return;
-
-        ptl2 = (pte_t *) PA2KA(GET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page)));
-
+        
+        pte_t *ptl2 = (pte_t *) PA2KA(GET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page)));
         if (GET_PTL3_FLAGS(ptl2, PTL2_INDEX(page)) & PAGE_NOT_PRESENT)
                 return;
-
-        ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));
-
+        
+        pte_t *ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));
+        
         /* Destroy the mapping. Setting to PAGE_NOT_PRESENT is not sufficient. */
         memsetb(&ptl3[PTL3_INDEX(page)], sizeof(pte_t), 0);
-
+        
         /*
          * Second, free all empty tables along the way from PTL3 down to PTL0.
+         *
          */
         
-        /* check PTL3 */
+        /* Check PTL3 */
+        bool empty = true;
+        
+        unsigned int i;
         for (i = 0; i < PTL3_ENTRIES; i++) {
                 if (PTE_VALID(&ptl3[i])) {
@@ -160 +158 @@
                 }
         }
+        
         if (empty) {
                 /*
                  * PTL3 is empty.
                  * Release the frame and remove PTL3 pointer from preceding table.
+                 *
                  */
                 frame_free(KA2PA((uintptr_t) ptl3));
-                if (PTL2_ENTRIES)
-                        memsetb(&ptl2[PTL2_INDEX(page)], sizeof(pte_t), 0);
-                else if (PTL1_ENTRIES)
-                        memsetb(&ptl1[PTL1_INDEX(page)], sizeof(pte_t), 0);
-                else
-                        memsetb(&ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);
+#if (PTL2_ENTRIES != 0)
+                memsetb(&ptl2[PTL2_INDEX(page)], sizeof(pte_t), 0);
+#elif (PTL1_ENTRIES != 0)
+                memsetb(&ptl1[PTL1_INDEX(page)], sizeof(pte_t), 0);
+#else
+                memsetb(&ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);
+#endif
         } else {
                 /*
@@ -177 +178 @@
                  * Therefore, there must be a path from PTL0 to PTL3 and
                  * thus nothing to free in higher levels.
-                 */
-                return;
-        }
-        
-        /* check PTL2, empty is still true */
-        if (PTL2_ENTRIES) {
-                for (i = 0; i < PTL2_ENTRIES; i++) {
-                        if (PTE_VALID(&ptl2[i])) {
-                                empty = false;
-                                break;
-                        }
+                 *
+                 */
+                return;
+        }
+        
+        /* Check PTL2, empty is still true */
+#if (PTL2_ENTRIES != 0)
+        for (i = 0; i < PTL2_ENTRIES; i++) {
+                if (PTE_VALID(&ptl2[i])) {
+                        empty = false;
+                        break;
                 }
-                if (empty) {
-                        /*
-                         * PTL2 is empty.
-                         * Release the frame and remove PTL2 pointer from preceding table.
-                         */
-                        frame_free(KA2PA((uintptr_t) ptl2));
-                        if (PTL1_ENTRIES)
-                                memsetb(&ptl1[PTL1_INDEX(page)], sizeof(pte_t), 0);
-                        else
-                                memsetb(&ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);
+        }
+        
+        if (empty) {
+                /*
+                 * PTL2 is empty.
+                 * Release the frame and remove PTL2 pointer from preceding table.
+                 *
+                 */
+                frame_free(KA2PA((uintptr_t) ptl2));
+#if (PTL1_ENTRIES != 0)
+                memsetb(&ptl1[PTL1_INDEX(page)], sizeof(pte_t), 0);
+#else
+                memsetb(&ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);
+#endif
+        } else {
+                /*
+                 * PTL2 is not empty.
+                 * Therefore, there must be a path from PTL0 to PTL2 and
+                 * thus nothing to free in higher levels.
+                 *
+                 */
+                return;
+        }
+#endif /* PTL2_ENTRIES != 0 */
+        
+        /* check PTL1, empty is still true */
+#if (PTL1_ENTRIES != 0)
+        for (i = 0; i < PTL1_ENTRIES; i++) {
+                if (PTE_VALID(&ptl1[i])) {
+                        empty = false;
+                        break;
                 }
-                else {
-                        /*
-                         * PTL2 is not empty.
-                         * Therefore, there must be a path from PTL0 to PTL2 and
-                         * thus nothing to free in higher levels.
-                         */
-                        return;
-                }
-        }
-
-        /* check PTL1, empty is still true */
-        if (PTL1_ENTRIES) {
-                for (i = 0; i < PTL1_ENTRIES; i++) {
-                        if (PTE_VALID(&ptl1[i])) {
-                                empty = false;
-                                break;
-                        }
-                }
-                if (empty) {
-                        /*
-                         * PTL1 is empty.
-                         * Release the frame and remove PTL1 pointer from preceding table.
-                         */
-                        frame_free(KA2PA((uintptr_t) ptl1));
-                        memsetb(&ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);
-                }
-        }
-
+        }
+        
+        if (empty) {
+                /*
+                 * PTL1 is empty.
+                 * Release the frame and remove PTL1 pointer from preceding table.
+                 *
+                 */
+                frame_free(KA2PA((uintptr_t) ptl1));
+                memsetb(&ptl0[PTL0_INDEX(page)], sizeof(pte_t), 0);
+        }
+#endif /* PTL1_ENTRIES != 0 */
 }
 
@@ -234 +240 @@
  * Find mapping for virtual page.
  *
- * The page table must be locked and interrupts must be disabled.
- *
- * @param as Address space to which page belongs.
+ * @param as   Address space to which page belongs.
  * @param page Virtual page.
  *
- * @return NULL if there is no such mapping; entry from PTL3 describing the mapping otherwise.
+ * @return NULL if there is no such mapping; entry from PTL3 describing
+ *         the mapping otherwise.
+ *
  */
 pte_t *pt_mapping_find(as_t *as, uintptr_t page)
 {
-        pte_t *ptl0, *ptl1, *ptl2, *ptl3;
-
-        ptl0 = (pte_t *) PA2KA((uintptr_t) as->genarch.page_table);
-
+        ASSERT(page_table_locked(as));
+
+        pte_t *ptl0 = (pte_t *) PA2KA((uintptr_t) as->genarch.page_table);
         if (GET_PTL1_FLAGS(ptl0, PTL0_INDEX(page)) & PAGE_NOT_PRESENT)
                 return NULL;
-
-        ptl1 = (pte_t *) PA2KA(GET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page)));
-
+        
+        pte_t *ptl1 = (pte_t *) PA2KA(GET_PTL1_ADDRESS(ptl0, PTL0_INDEX(page)));
         if (GET_PTL2_FLAGS(ptl1, PTL1_INDEX(page)) & PAGE_NOT_PRESENT)
                 return NULL;
-
-        ptl2 = (pte_t *) PA2KA(GET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page)));
-
+        
+        pte_t *ptl2 = (pte_t *) PA2KA(GET_PTL2_ADDRESS(ptl1, PTL1_INDEX(page)));
         if (GET_PTL3_FLAGS(ptl2, PTL2_INDEX(page)) & PAGE_NOT_PRESENT)
                 return NULL;
-
-        ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));
-
+        
+        pte_t *ptl3 = (pte_t *) PA2KA(GET_PTL3_ADDRESS(ptl2, PTL2_INDEX(page)));
+        
         return &ptl3[PTL3_INDEX(page)];
 }