diff -urN 2.3.99-pre6-pre3/mm/filemap.c swap-entry-2/mm/filemap.c
--- 2.3.99-pre6-pre3/mm/filemap.c Tue Apr 18 16:11:42 2000
+++ swap-entry-2/mm/filemap.c Thu Apr 20 02:33:05 2000
@@ -300,6 +300,8 @@
if (PageSwapCache(page)) {
spin_unlock(&pagecache_lock);
__delete_from_swap_cache(page);
+ /* the page is local to us now */
+ page->flags &= ~(1UL << PG_swap_entry);
goto made_inode_progress;
}
diff -urN 2.3.99-pre6-pre3/mm/highmem.c swap-entry-2/mm/highmem.c
--- 2.3.99-pre6-pre3/mm/highmem.c Mon Apr 3 03:21:59 2000
+++ swap-entry-2/mm/highmem.c Thu Apr 20 02:33:05 2000
@@ -75,7 +75,7 @@
/* Preserve the caching of the swap_entry. */
highpage->index = page->index;
- highpage->mapping = page->mapping;
+ highpage->flags = page->flags;
/*
* We can just forget the old page since
diff -urN 2.3.99-pre6-pre3/mm/memory.c swap-entry-2/mm/memory.c
--- 2.3.99-pre6-pre3/mm/memory.c Tue Apr 18 16:11:42 2000
+++ swap-entry-2/mm/memory.c Thu Apr 20 02:33:05 2000
@@ -837,6 +837,7 @@
*/
switch (page_count(old_page)) {
case 2:
+ case 3:
/*
* Lock the page so that no one can look it up from
* the swap cache, grab a reference and start using it.
@@ -879,7 +880,19 @@
new_page = old_page;
}
spin_unlock(&tsk->mm->page_table_lock);
- __free_page(new_page);
+ /*
+ * We're releasing a page, it can be an anonymous
+ * page as well. Since we don't hold any lock (except
+ * the mmap_sem semaphore) the other user of the anonymous
+ * page may have released it from under us and now we
+ * could be the only owner of the page, thus put_page_testzero() can
+ * return 1, and we have to clear the swap-entry
+ * bitflag in such case.
+ */
+ if (put_page_testzero(new_page)) {
+ new_page->flags &= ~(1UL << PG_swap_entry);
+ __free_pages_ok(new_page, 0);
+ }
return 1;
bad_wp_page:
diff -urN 2.3.99-pre6-pre3/mm/page_alloc.c swap-entry-2/mm/page_alloc.c
--- 2.3.99-pre6-pre3/mm/page_alloc.c Tue Apr 18 16:11:42 2000
+++ swap-entry-2/mm/page_alloc.c Thu Apr 20 02:33:05 2000
@@ -110,6 +110,8 @@
BUG();
if (PageDecrAfter(page))
BUG();
+ if (PageSwapEntry(page))
+ BUG();
zone = page->zone;
diff -urN 2.3.99-pre6-pre3/mm/swap_state.c swap-entry-2/mm/swap_state.c
--- 2.3.99-pre6-pre3/mm/swap_state.c Tue Apr 18 16:11:42 2000
+++ swap-entry-2/mm/swap_state.c Thu Apr 20 02:33:05 2000
@@ -126,9 +126,14 @@
UnlockPage(page);
}
- ClearPageSwapEntry(page);
-
- __free_page(page);
+ /*
+ * Only the last unmap have to lose the swap entry
+ * information that we have cached into page->index.
+ */
+ if (put_page_testzero(page)) {
+ page->flags &= ~(1UL << PG_swap_entry);
+ __free_pages_ok(page, 0);
+ }
}
diff -urN 2.3.99-pre6-pre3/mm/swapfile.c swap-entry-2/mm/swapfile.c
--- 2.3.99-pre6-pre3/mm/swapfile.c Tue Apr 18 16:11:42 2000
+++ swap-entry-2/mm/swapfile.c Thu Apr 20 02:33:05 2000
@@ -212,22 +212,22 @@
/* We have the old entry in the page offset still */
if (!page->index)
- goto new_swap_entry;
+ goto null_swap_entry;
entry.val = page->index;
type = SWP_TYPE(entry);
if (type >= nr_swapfiles)
- goto new_swap_entry;
+ goto bad_nofile;
+ swap_list_lock();
p = type + swap_info;
if ((p->flags & SWP_WRITEOK) != SWP_WRITEOK)
- goto new_swap_entry;
+ goto unlock_list;
offset = SWP_OFFSET(entry);
if (offset >= p->max)
- goto new_swap_entry;
+ goto bad_offset;
/* Has it been re-used for something else? */
- swap_list_lock();
swap_device_lock(p);
if (p->swap_map[offset])
- goto unlock_new_swap_entry;
+ goto unlock;
/* We're cool, we can just use the old one */
p->swap_map[offset] = 1;
@@ -236,11 +236,24 @@
swap_list_unlock();
return entry;
-unlock_new_swap_entry:
+unlock:
swap_device_unlock(p);
+unlock_list:
swap_list_unlock();
+clear_swap_entry:
+ ClearPageSwapEntry(page);
new_swap_entry:
return get_swap_page();
+
+null_swap_entry:
+ printk(KERN_WARNING __FUNCTION__ " null swap entry\n");
+ goto clear_swap_entry;
+bad_nofile:
+ printk(KERN_WARNING __FUNCTION__ " nonexistent swap file\n");
+ goto clear_swap_entry;
+bad_offset:
+ printk(KERN_WARNING __FUNCTION__ " bad offset\n");
+ goto unlock_list;
}
/*
@@ -263,8 +276,11 @@
/* If this entry is swap-cached, then page must already
hold the right address for any copies in physical
memory */
- if (pte_page(pte) != page)
+ if (pte_page(pte) != page) {
+ if (page->index == entry.val)
+ ClearPageSwapEntry(page);
return;
+ }
/* We will be removing the swap cache in a moment, so... */
set_pte(dir, pte_mkdirty(pte));
return;
@@ -418,8 +444,10 @@
shm_unuse(entry, page);
/* Now get rid of the extra reference to the temporary
page we've been using. */
- if (PageSwapCache(page))
+ if (PageSwapCache(page)) {
delete_from_swap_cache(page);
+ ClearPageSwapEntry(page);
+ }
__free_page(page);
/*
* Check for and clear any overflowed swap map counts.