release_extent_buffer(eb);
}
+static void btree_clear_page_dirty(struct page *page)
+{
+ ASSERT(PageDirty(page));
+ ASSERT(PageLocked(page));
+ clear_page_dirty_for_io(page);
+ xa_lock_irq(&page->mapping->i_pages);
+ if (!PageDirty(page))
+ __xa_clear_mark(&page->mapping->i_pages,
+ page_index(page), PAGECACHE_TAG_DIRTY);
+ xa_unlock_irq(&page->mapping->i_pages);
+}
+
+static void clear_subpage_extent_buffer_dirty(const struct extent_buffer *eb)
+{
+ struct btrfs_fs_info *fs_info = eb->fs_info;
+ struct page *page = eb->pages[0];
+ bool last;
+
+ /* btree_clear_page_dirty() needs page locked */
+ lock_page(page);
+ last = btrfs_subpage_clear_and_test_dirty(fs_info, page, eb->start,
+ eb->len);
+ if (last)
+ btree_clear_page_dirty(page);
+ unlock_page(page);
+ WARN_ON(atomic_read(&eb->refs) == 0);
+}
+
void clear_extent_buffer_dirty(const struct extent_buffer *eb)
{
int i;
int num_pages;
struct page *page;
+ if (eb->fs_info->sectorsize < PAGE_SIZE)
+ return clear_subpage_extent_buffer_dirty(eb);
+
num_pages = num_extent_pages(eb);
for (i = 0; i < num_pages; i++) {
page = eb->pages[i];
if (!PageDirty(page))
continue;
-
lock_page(page);
- WARN_ON(!PagePrivate(page));
-
- clear_page_dirty_for_io(page);
- xa_lock_irq(&page->mapping->i_pages);
- if (!PageDirty(page))
- __xa_clear_mark(&page->mapping->i_pages,
- page_index(page), PAGECACHE_TAG_DIRTY);
- xa_unlock_irq(&page->mapping->i_pages);
+ btree_clear_page_dirty(page);
ClearPageError(page);
unlock_page(page);
}
WARN_ON(atomic_read(&eb->refs) == 0);
WARN_ON(!test_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags));
- if (!was_dirty)
- for (i = 0; i < num_pages; i++)
- set_page_dirty(eb->pages[i]);
+ if (!was_dirty) {
+ bool subpage = eb->fs_info->sectorsize < PAGE_SIZE;
+ /*
+ * For subpage case, we can have other extent buffers in the
+ * same page, and in clear_subpage_extent_buffer_dirty() we
+ * have to clear page dirty without subpage lock held.
+ * This can cause race where our page gets dirty cleared after
+ * we just set it.
+ *
+ * Thankfully, clear_subpage_extent_buffer_dirty() has locked
+ * its page for other reasons, we can use page lock to prevent
+ * the above race.
+ */
+ if (subpage)
+ lock_page(eb->pages[0]);
+ for (i = 0; i < num_pages; i++)
+ btrfs_page_set_dirty(eb->fs_info, eb->pages[i],
+ eb->start, eb->len);
+ if (subpage)
+ unlock_page(eb->pages[0]);
+ }
#ifdef CONFIG_BTRFS_DEBUG
for (i = 0; i < num_pages; i++)
ASSERT(PageDirty(eb->pages[i]));