btrfs_writepage_cow_fixup 2900 fs/btrfs/ctree.h int btrfs_writepage_cow_fixup(struct page *page, u64 start, u64 end);
btrfs_writepage_cow_fixup 3434 fs/btrfs/extent_io.c 	ret = btrfs_writepage_cow_fixup(page, start, page_end);