update lab1-8 codes and docs. now version is 0.2

code/lab7/kern/mm/kmalloc.c

@@ -487,7 +487,7 @@ check_slab(void) {
     void *v0, *v1;
 
     size_t nr_free_pages_store = nr_free_pages();
-    size_t slab_allocated_store = slab_allocated();
+    size_t kernel_allocated_store = slab_allocated();
 
     /* slab must be empty now */
     check_slab_empty();
@@ -633,7 +633,7 @@ check_pass:
     check_slab_empty();
     assert(slab_allocated() == 0);
     assert(nr_free_pages_store == nr_free_pages());
-    assert(slab_allocated_store == slab_allocated());
+    assert(kernel_allocated_store == slab_allocated());
 
     cprintf("check_slab() succeeded!\n");
 }

code/lab7/kern/mm/swap.c

@@ -184,7 +184,7 @@ check_swap(void)
      list_entry_t *le = &free_list;
      while ((le = list_next(le)) != &free_list) {
         struct Page *p = le2page(le, page_link);
-        //assert(PageProperty(p));
+        assert(PageProperty(p));
         count ++, total += p->property;
      }
      assert(total == nr_free_pages());
@@ -277,7 +277,7 @@ check_swap(void)
          struct Page *p = le2page(le, page_link);
          count --, total -= p->property;
      }
-         cprintf("count is %d, total is %d\n",count,total);
+     cprintf("count is %d, total is %d\n",count,total);
      //assert(count == 0);
      
      cprintf("check_swap() succeeded!\n");

code/lab7/kern/mm/vmm.c

@@ -460,6 +460,15 @@ do_pgfault(struct mm_struct *mm, uint32_t error_code, uintptr_t addr) {
     *    page_insert ： build the map of phy addr of an Page with the linear addr la
     *    swap_map_swappable ： set the page swappable
     */
+    /*
+     * LAB5 CHALLENGE ( the implmentation Copy on Write)
+		There are 2 situlations when code comes here.
+		  1) *ptep & PTE_P == 1, it means one process try to write a readonly page. 
+		     If the vma includes this addr is writable, then we can set the page writable by rewrite the *ptep.
+		     This method could be used to implement the Copy on Write (COW) thchnology(a fast fork process method).
+		  2) *ptep & PTE_P == 0 & but *ptep!=0, it means this pte is a  swap entry.
+		     We should add the LAB3's results here.
+     */
         if(swap_init_ok) {
             struct Page *page=NULL;
                                     //(1）According to the mm AND addr, try to load the content of right disk page