Re: [PATCH v5 3/6] libnvdimm: add dax_dev sync flag

Pankaj Gupta
2019-04-11T15:39:21Z

Hi Dan,

Thank you for the review.

> >
> > This patch adds 'DAXDEV_SYNC' flag which is set
> > for nd_region doing synchronous flush. This later
> > is used to disable MAP_SYNC functionality for
> > ext4 & xfs filesystem for devices don't support
> > synchronous flush.
> >
> > Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
> > ---
> > drivers/dax/bus.c | 2 +-
> > drivers/dax/super.c | 13 ++++++++++++-
> > drivers/md/dm.c | 2 +-
> > drivers/nvdimm/pmem.c | 3 ++-
> > drivers/nvdimm/region_devs.c | 7 +++++++
> > include/linux/dax.h | 9 +++++++--
> > include/linux/libnvdimm.h | 1 +
> > 7 files changed, 31 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
> > index 2109cfe80219..431bf7d2a7f9 100644
> > --- a/drivers/dax/bus.c
> > +++ b/drivers/dax/bus.c
> > @@ -388,7 +388,7 @@ struct dev_dax *__devm_create_dev_dax(struct dax_region
> > *dax_region, int id,
> > * No 'host' or dax_operations since there is no access to this
> > * device outside of mmap of the resulting character device.
> > */
> > - dax_dev = alloc_dax(dev_dax, NULL, NULL);
> > + dax_dev = alloc_dax(dev_dax, NULL, NULL, true);
>
> I find apis that take a boolean as unreadable. What does 'true' mean?
> It wastes time to go look at the function definition vs something
> like:
>
> alloc_dax(dev_dax, NULL, NULL, DAXDEV_F_SYNC);

Agree. Will change as suggested.

Best regards,
Pankaj
>