2020-01-16 10:02:43

by Jan Kara

Subject: Re: [RFC PATCH V2 05/12] fs: remove unneeded IS_DAX() check

On Fri 10-01-20 11:29:35, [email protected] wrote:
> From: Ira Weiny <[email protected]>
>
> The IS_DAX() check in io_is_direct() causes a race between changing the
> DAX mode and creating the iocb flags.
>
> Remove the check because DAX now emulates the page cache API and
> therefore it does not matter if the file mode is DAX or not when the
> iocb flags are created.
>
> Signed-off-by: Ira Weiny <[email protected]>

The patch looks good to me. You can add:

Reviewed-by: Jan Kara <[email protected]>

Honza

> ---
> include/linux/fs.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index d7584bcef5d3..e11989502eac 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -3365,7 +3365,7 @@ extern int file_update_time(struct file *file);
>
> static inline bool io_is_direct(struct file *filp)
> {
> - return (filp->f_flags & O_DIRECT) || IS_DAX(filp->f_mapping->host);
> + return (filp->f_flags & O_DIRECT);
> }
>
> static inline bool vma_is_dax(struct vm_area_struct *vma)
> --
> 2.21.0
>
--
Jan Kara <[email protected]>
SUSE Labs, CR

2020-01-16 18:48:55

by Ira Weiny

Subject: Re: [RFC PATCH V2 05/12] fs: remove unneeded IS_DAX() check

On Thu, Jan 16, 2020 at 10:38:07AM +0100, Jan Kara wrote:
> On Fri 10-01-20 11:29:35, [email protected] wrote:
> > From: Ira Weiny <[email protected]>
> >
> > The IS_DAX() check in io_is_direct() causes a race between changing the
> > DAX mode and creating the iocb flags.
> >
> > Remove the check because DAX now emulates the page cache API and
> > therefore it does not matter if the file mode is DAX or not when the
> > iocb flags are created.
> >
> > Signed-off-by: Ira Weiny <[email protected]>
>
> The patch looks good to me. You can add:
>
> Reviewed-by: Jan Kara <[email protected]>

Thanks,
Ira

>
> Honza
>
> > ---
> > include/linux/fs.h | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/include/linux/fs.h b/include/linux/fs.h
> > index d7584bcef5d3..e11989502eac 100644
> > --- a/include/linux/fs.h
> > +++ b/include/linux/fs.h
> > @@ -3365,7 +3365,7 @@ extern int file_update_time(struct file *file);
> >
> > static inline bool io_is_direct(struct file *filp)
> > {
> > - return (filp->f_flags & O_DIRECT) || IS_DAX(filp->f_mapping->host);
> > + return (filp->f_flags & O_DIRECT);
> > }
> >
> > static inline bool vma_is_dax(struct vm_area_struct *vma)
> > --
> > 2.21.0
> >
> --
> Jan Kara <[email protected]>
> SUSE Labs, CR