return 0;
write_lock_irq(&mapping->tree_lock);
- if (PageDirty(page)) {
- write_unlock_irq(&mapping->tree_lock);
- return 0;
- }
+ if (PageDirty(page))
+ goto failed;
+ if (page_count(page) != 2) /* caller's ref + pagecache ref */
+ goto failed;
BUG_ON(PagePrivate(page));
__remove_from_page_cache(page);
ClearPageUptodate(page);
page_cache_release(page); /* pagecache ref */
return 1;
+failed:
+ write_unlock_irq(&mapping->tree_lock);
+ return 0;
}
/**
pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i];
+ pgoff_t index;
+ int lock_failed;
- if (TestSetPageLocked(page)) {
- next++;
- continue;
- }
- if (page->index > next)
- next = page->index;
+ lock_failed = TestSetPageLocked(page);
+
+ /*
+ * We really shouldn't be looking at the ->index of an
+ * unlocked page. But we're not allowed to lock these
+ * pages. So we rely upon nobody altering the ->index
+ * of this (pinned-by-us) page.
+ */
+ index = page->index;
+ if (index > next)
+ next = index;
next++;
+ if (lock_failed)
+ continue;
+
if (PageDirty(page) || PageWriteback(page))
goto unlock;
if (page_mapped(page))
{
return invalidate_mapping_pages(mapping, 0, ~0UL);
}
-
EXPORT_SYMBOL(invalidate_inode_pages);
+/*
+ * This is like invalidate_complete_page(), except it ignores the page's
+ * refcount. We do this because invalidate_inode_pages2() needs stronger
+ * invalidation guarantees, and cannot afford to leave pages behind because
+ * shrink_list() has a temp ref on them, or because they're transiently sitting
+ * in the lru_cache_add() pagevecs.
+ */
+static int
+invalidate_complete_page2(struct address_space *mapping, struct page *page)
+{
+ if (page->mapping != mapping)
+ return 0;
+
+ if (PagePrivate(page) && !try_to_release_page(page, GFP_KERNEL))
+ return 0;
+
+ write_lock_irq(&mapping->tree_lock);
+ if (PageDirty(page))
+ goto failed;
+
+ BUG_ON(PagePrivate(page));
+ __remove_from_page_cache(page);
+ write_unlock_irq(&mapping->tree_lock);
+ ClearPageUptodate(page);
+ page_cache_release(page); /* pagecache ref */
+ return 1;
+failed:
+ write_unlock_irq(&mapping->tree_lock);
+ return 0;
+}
+
/**
* invalidate_inode_pages2_range - remove range of pages from an address_space
* @mapping: the address_space
}
}
was_dirty = test_clear_page_dirty(page);
- if (!invalidate_complete_page(mapping, page)) {
+ if (!invalidate_complete_page2(mapping, page)) {
if (was_dirty)
set_page_dirty(page);
ret = -EIO;