From e11b2ef0c606ab516a4344aeea1dbba22cb1fe5d Mon Sep 17 00:00:00 2001
From: manuel <manuel@mausz.at>
Date: Thu, 21 Jun 2012 16:47:23 +0200
Subject: initial implementation of memory mapped files

---
 vm/page.c | 43 +++++++------------------------------------
 1 file changed, 7 insertions(+), 36 deletions(-)

(limited to 'vm/page.c')

diff --git a/vm/page.c b/vm/page.c
index 336353e..2853497 100644
--- a/vm/page.c
+++ b/vm/page.c
@@ -2,6 +2,7 @@
 #include "filesys/file.h"
 #include "userprog/process.h"
 #include "threads/thread.h"
+#include "threads/vaddr.h"
 #include "threads/malloc.h"
 #include "threads/palloc.h"
 #include "vm/page.h"
@@ -11,8 +12,6 @@ static bool page_table_cmp_less (const struct hash_elem *a, const struct hash_el
     void *aux UNUSED);
 static void page_table_entry_free (struct hash_elem *e, void *aux UNUSED);
 static bool page_table_insert (struct hash *ht, struct page_table_entry *pte);
-static bool page_load_segment (struct page_table_entry *pte);
-static bool page_load_mmf (struct page_table_entry *pte);
 
 /* initialize page table structure */
 void
@@ -69,23 +68,20 @@ page_table_insert (struct hash *ht, struct page_table_entry *pte)
 /* inserts a new entry of type segment into the page table
    returns false if entry is invalid or already in the table */
 bool
-page_table_insert_segment (struct file *file, off_t ofs, uint8_t *upage,
-    uint32_t read_bytes, uint32_t zero_bytes, bool writable)
+page_table_insert_segment (struct hash *ht, struct file *file, off_t ofs,
+    uint8_t *upage, uint32_t read_bytes, bool writable)
 {
   struct page_table_entry *pte = malloc (sizeof *pte);
   if (pte == NULL)
     return false;
 
   pte->upage  = upage;
-  pte->type   = PAGE_SEGMENT;
   pte->loaded = false;
   pte->segment.file       = file;
   pte->segment.ofs        = ofs;
   pte->segment.read_bytes = read_bytes;
-  pte->segment.zero_bytes = zero_bytes;
   pte->segment.writable   = writable;
-
-  return page_table_insert (&thread_current ()->page_table, pte);
+  return page_table_insert (ht, pte);
 }
 
 /* fetch an entry from the page table. returns NULL if not found */
@@ -105,28 +101,11 @@ page_table_fetch (struct hash *ht, void *upage)
 bool
 page_load (struct page_table_entry *pte)
 {
+  struct segment *data;
   if (pte->loaded)
     return true;
 
-  switch (pte->type)
-    {
-      case PAGE_SEGMENT:
-        return page_load_segment (pte);
-      case PAGE_MEMORY_MAPPED_FILE:
-        return page_load_mmf (pte);
-      default:
-        ASSERT (false);
-        break;
-    }
-  return false;
-}
-
-/* load the segment data page */
-static bool
-page_load_segment (struct page_table_entry *pte)
-{
-  struct segment *data = &pte->segment;
-
+  data = &pte->segment;
   file_seek (data->file, data->ofs);
 
   /* Get a page of memory. */
@@ -141,7 +120,7 @@ page_load_segment (struct page_table_entry *pte)
       palloc_free_page (kpage);
       return false;
     }
-  memset (kpage + data->read_bytes, 0, data->zero_bytes);
+  memset (kpage + data->read_bytes, 0, PGSIZE - data->read_bytes);
 
   /* Add the page to the process's address space. */
   if (!process_install_page (pte->upage, kpage, data->writable))
@@ -153,11 +132,3 @@ page_load_segment (struct page_table_entry *pte)
   pte->loaded = true;
   return true;
 }
-
-/* load the memory mappged file page */
-static bool
-page_load_mmf (struct page_table_entry *pte)
-{
-  //TODO: implement
-  return false;
-}
-- 
cgit v1.2.3