diff --git a/src/userprog/exception.c b/src/userprog/exception.c index c4bfa97..ca2911c 100644 --- a/src/userprog/exception.c +++ b/src/userprog/exception.c @@ -271,9 +271,7 @@ fetch_page (void *upage, bool write) size_t swap_slot = page_get_swap (t, upage); swap_in (kpage, swap_slot); - hash_delete (&thread_current ()->pages, &page->elem); lock_release (&page->lock); - page_cleanup (&page->elem, NULL); bool writeable = pagedir_is_writable (t->pagedir, upage); @@ -293,11 +291,6 @@ fetch_page (void *upage, bool write) case PAGE_MMAP: case PAGE_FILE: success = page_load_file (page, page->writable); - if (success && page->type == PAGE_FILE) - { - hash_delete (&thread_current ()->pages, &page->elem); - page_cleanup (&page->elem, NULL); - } break; default: return false; diff --git a/src/vm/page.c b/src/vm/page.c index d1f9f64..56c6f30 100644 --- a/src/vm/page.c +++ b/src/vm/page.c @@ -39,20 +39,24 @@ static void page_flag_swap (uint32_t *pte, bool set); static void page_set_swap (struct thread *owner, uint32_t *pte, size_t swap_slot); +// TODO: Deal with NULL malloc returns /* Swap out 'owner' process's 'upage' stored at 'kpage'. Then, allocate and insert a new page entry into the user process thread's SPT representing this swapped out page. */ struct page_entry * page_insert_swapped (void *upage, void *kpage, struct thread *owner) { - /* 1. Initialize swapped page entry. */ - struct page_entry *page = malloc(sizeof (struct page_entry)); + struct page_entry *page = page_get (upage); if (page == NULL) - return NULL; - - page->upage = upage; - lock_init (&page->lock); + { + page = malloc (sizeof (struct page_entry)); + if (page == NULL) + return NULL; + page->upage = upage; + lock_init (&page->lock); + hash_insert (&owner->pages, &page->elem); + } /* Mark page as 'swapped' and flag the page directory as having been modified *before* eviction begins to prevent the owner of the @@ -60,13 +64,9 @@ page_insert_swapped (void *upage, void *kpage, struct thread *owner) /* TODO: We need to stop the process from destroying pagedir mid-eviction, as this could render the page table entry invalid. */ uint32_t *pte = lookup_page (owner->pagedir, upage, false); - ASSERT (pte != NULL); page_flag_swap (pte, true); lock_acquire (&page->lock); - struct hash_elem *elem = hash_insert (&owner->pages, &page->elem); - ASSERT(elem == NULL); - pagedir_clear_page (owner->pagedir, upage); size_t swap_slot = swap_out (kpage); @@ -94,6 +94,7 @@ page_insert_file (struct file *file, off_t ofs, void *upage, page->read_bytes = read_bytes; page->zero_bytes = zero_bytes; page->writable = writable; + lock_init (&page->lock); hash_insert (&thread_current ()->pages, &page->elem); return page; diff --git a/src/vm/page.h b/src/vm/page.h index 893317d..be7a0aa 100644 --- a/src/vm/page.h +++ b/src/vm/page.h @@ -7,8 +7,7 @@ enum page_type { PAGE_FILE, - PAGE_MMAP, - PAGE_EMPTY + PAGE_MMAP }; struct page_entry {