full mmap implementation

2 files changed, 10 insertions, 7 deletions

diff --git a/userprog/process.c b/userprog/process.c
index f399038..80e327d 100644
--- a/userprog/process.c
+++ b/userprog/process.c
@@ -151,13 +151,11 @@ start_process (void *aux)
   /* If process startup failed, quit. */
   if (thread->process == NULL)  {
     if (process != NULL) {
-      //TODO: free mmap table + page table?
-
       /* close/free memory mapped files */
-      //mmap_table_free (&process->mmap_table);
+      mmap_table_free (&process->mmap_table);
 
       /* free page table */
-      //page_table_free (&thread->page_table);
+      page_table_free (&thread->page_table);
 
       if (process->fd_table.fds != NULL)
         palloc_free_page (process->fd_table.fds);
diff --git a/userprog/syscall.c b/userprog/syscall.c
index 14cbaab..9da3044 100644
--- a/userprog/syscall.c
+++ b/userprog/syscall.c
@@ -576,9 +576,10 @@ static int
 syscall_mmap (void *sp, bool *segfault)
 {
   int fd;
-  void *addr, *offset;
+  uint8_t *addr, *offset;
   struct file *file, *file2;
   off_t len;
+  struct thread *thread = thread_current ();
 
   /* get arguments */
   if (! copy_from_user (&fd, STACK_ADDR (sp,1)) ||
@@ -605,11 +606,15 @@ syscall_mmap (void *sp, bool *segfault)
   if (len <= 0)
     return -1;
 
-  /* check if the pages don't overlap any existing pages */
+  /* check if the pages don't overlap any existing pages AND mapped pages */
   offset = addr;
   while(offset < addr + len)
   {
-    if (page_table_fetch (&thread_current ()->page_table, offset))
+    /* check for pages either loaded or not */
+    if (page_table_fetch (&thread->page_table, offset))
+      return -1;
+    /* check for already loaded pages not in page table (e.g. stack) */
+    if (pagedir_get_page (thread->pagedir, offset))
       return -1;
     offset += PGSIZE;
   }