btrfs_release_extent_buffer_page() can't handle dummy extent that allocated by btrfs_clone_extent_buffer() properly.
Reference count of pages that allocated by btrfs_clone_extent_buffer() was 2, 1 by alloc_page(), and another by attach_extent_buffer_page(). Signed-off-by: Chien-Kuan Yeh <[email protected]> Signed-off-by: Forrest Liu <[email protected]> --- fs/btrfs/extent_io.c | 43 ++++++++++++++++++++++--------------------- 1 file changed, 22 insertions(+), 21 deletions(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index dab8af4..58a5183 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -4555,32 +4555,33 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb) do { index--; page = eb->pages[index]; - if (page && mapped) { + if (page && mapped) spin_lock(&page->mapping->private_lock); + /* + * We do this since we'll remove the pages after we've + * removed the eb from the radix tree, so we could race + * and have this page now attached to the new eb. So + * only clear page_private if it's still connected to + * this eb. + */ + if (PagePrivate(page) && + page->private == (unsigned long)eb) { + BUG_ON(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)); + BUG_ON(PageDirty(page)); + BUG_ON(PageWriteback(page)); /* - * We do this since we'll remove the pages after we've - * removed the eb from the radix tree, so we could race - * and have this page now attached to the new eb. So - * only clear page_private if it's still connected to - * this eb. + * We need to make sure we haven't be attached + * to a new eb. */ - if (PagePrivate(page) && - page->private == (unsigned long)eb) { - BUG_ON(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)); - BUG_ON(PageDirty(page)); - BUG_ON(PageWriteback(page)); - /* - * We need to make sure we haven't be attached - * to a new eb. - */ - ClearPagePrivate(page); - set_page_private(page, 0); - /* One for the page private */ - page_cache_release(page); - } + ClearPagePrivate(page); + set_page_private(page, 0); + /* One for the page private */ + page_cache_release(page); + } + + if (page && mapped) spin_unlock(&page->mapping->private_lock); - } if (page) { /* One for when we alloced the page */ page_cache_release(page); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
