lab pgtbl: finishpgtbl

1 files changed, 27 insertions, 0 deletions

diff --git a/kernel/vm.c b/kernel/vm.c
index 5c31e87..9c17fe7 100644
--- a/kernel/vm.c
+++ b/kernel/vm.c
@@ -449,3 +449,30 @@ copyinstr(pagetable_t pagetable, char *dst, uint64 srcva, uint64 max)
     return -1;
   }
 }
+
+static void
+walkprint(pagetable_t pgtbl, int level)
+{
+  for(int i = 0; i < 512; i++){
+    pte_t pte = pgtbl[i];
+    if(pte & PTE_V){
+      for(int j = 0; j < level; j++){
+        printf(" ..");
+      }
+      printf("%d: pte %p pa %p\n", i, pte, PTE2PA(pte));
+      if((pte & (PTE_R|PTE_W|PTE_X)) == 0){
+        // this PTE points to a lower-level page table.
+        walkprint((pagetable_t)PTE2PA(pte), level+1);
+      }
+    }
+  }
+}
+
+// Print the contents of a page table
+void
+vmprint(pagetable_t pgtbl)
+{
+  printf("page table %p\n", pgtbl);
+
+  walkprint(pgtbl, 1);
+}