An updated freevm.

4c0143d2 · Silas Boyd-Wickizer · 8d068b51 · 4c0143d2 · 4c0143d2 · 4c0143d2
--- a/Makefile
+++ b/Makefile
@@ -101,7 +101,7 @@ fs.img: mkfs README $(UPROGS)
 clean: 
 	rm -f *.o *.d *.asm *.sym initcode kernel bootother mkfs fs.img
-QEMUOPTS = -smp $(CPUS) -m 512
+QEMUOPTS = -smp $(CPUS) -m 512 -nographic
 qemu: kernel
 	$(QEMU) $(QEMUOPTS) -kernel kernel
 gdb: kernel

--- a/types.h
+++ b/types.h
@@ -15,7 +15,6 @@ typedef uint64 u64;
 typedef uint64 uptr;
 typedef uptr paddr;
 typedef u64 pme_t; // Page Map Entry (refers to any entry in any level)
 typedef pme_t pml4e_t;

--- a/vm.c
+++ b/vm.c
@@ -161,20 +161,40 @@ vma_free(void *p)
  kmfree(e);
 }
+static void
+freepm(pme_t *pm, int level)
+{
+  int i;
+  if (level != 0) {
+    for (i = 0; i < 512; i++) {
+      if (pm[i] & PTE_P)
+        freepm(p2v(PTE_ADDR(pm[i])), level - 1);
+    }
+  }
+  kfree(pm);
+}
 // Free a page table and all the physical memory pages
 // in the user part.
 static void
 freevm(pml4e_t *pml4)
 {
+  int k;
+  int i;
  if(pml4 == 0)
    panic("freevm: no pgdir");
-  cprintf("freevm: XXX leaking..\n");
-#if 0
+  // Don't free kernel portion of the pml4
-  for(i = 0; i < 1024; i++){
+  k = PX(3, PBASE);
-    if(pgdir[i] & PTE_P)
+  for (i = 0; i < k; i++) {
-      kfree(p2v(PTE_ADDR(pgdir[i])));
+    if (pml4[i] & PTE_P) {
+      freepm(p2v(PTE_ADDR(pml4[i])), 2);
    }
-#endif
+  }
  kfree(pml4);
 }