On Tue 22-01-13 15:11:24, Dmitry Monakhov wrote: > On Fri, 18 Jan 2013 13:00:37 +0100, Jan Kara <jack@xxxxxxx> wrote: > > When using indirect blocks there is no possibility to have any unwritten > > extents. So wait for them in ext4_ind_direct_IO() is just bogus. > But as soon as i remember indirect implementation may also be used by > extents based inodes 3074: ext4_ext_direct_IO > /* Use the old path for reads and writes beyond i_size. */ > if (rw != WRITE || final_size > inode->i_size) > return ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs); > > Am I missing ? Ah, that's a catch. Thanks for pointing that out! So my patch is wrong and that code path needs some cleaning and commenting. In particular I'm afraid using dioread_nolock for inodes with indirect map causes data exposure bugs when unlocked DIO read races with DIO write because such inodes don't support uninitialized extents. Honza -- Jan Kara <jack@xxxxxxx> SUSE Labs, CR -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
