On Fri, Sep 17, 2021 at 11:43:59AM +0100, David Howells wrote: > David Howells <dhowells@xxxxxxxxxx> wrote: > > > Would it be possible to get an IOCB_NO_READ_HOLE flag that causes a read to > > either fail entirely if there's a hole in the file or to stop at the hole, > > possibly returning -ENODATA if the hole is at the front of the file? > > > > Looking at iomap_dio_iter(), IOMAP_HOLE should be enabled in > > iomap_iter::iomap.type for this? Is it that simple? > > Actually, that's not the right thing. How about the attached - at least for > direct I/O? This looks pretty reasonable. We'll just need to make sure to reject the flag for the many file operations instances that do not support it.