On 2/24/12 3:49 PM, Jeff Moyer wrote: > Hi, > > For extent-based files, you can perform DIO to holes, as mentioned in > the comments in ext4_ext_direct_IO. However, that function passes > DIO_SKIP_HOLES to __blockdev_direct_IO, which is *really* confusing to > the uninitiated reader. The key, here, is that the get_block function > passed in, ext4_get_block_write, completely ignores the create flag that > is passed to it (the create flag is passed in from the direct I/O code, > which uses the DIO_SKIP_HOLES flag to determine whether or not it should > be cleared). > > This is a long-winded way of saying that the DIO_SKIP_HOLES flag is > ultimately ignored. So, in the interest of preserving sanity, I propose > the following patch. > > Cheers, > Jeff > > Signed-off-by: Jeff Moyer <jmoyer@xxxxxxxxxx> Thank you sir. Reviewed-by: Eric Sandeen <sandeen@xxxxxxxxxx> > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index feaa82f..521ca03 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -2940,7 +2940,7 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb, > ext4_get_block_write, > ext4_end_io_dio, > NULL, > - DIO_LOCKING | DIO_SKIP_HOLES); > + DIO_LOCKING); > if (iocb->private) > EXT4_I(inode)->cur_aio_dio = NULL; > /* > -- > 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 -- 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
