On Thu, 27 Sep 2018 09:05:20 -0400 Eric Farman <farman@xxxxxxxxxxxxx> wrote: > On 09/27/2018 07:13 AM, Cornelia Huck wrote: > > On Fri, 21 Sep 2018 22:40:12 +0200 > > Eric Farman <farman@xxxxxxxxxxxxx> wrote: > > > >> In the event that we want to change the layout of the ccw_io_region in the > >> future[1], it might be easier to work with it as a pointer within the > >> vfio_ccw_private struct rather than an embedded struct. > >> > >> [1] https://patchwork.kernel.org/comment/22228541/ > >> > >> Signed-off-by: Eric Farman <farman@xxxxxxxxxxxxx> > >> --- > >> drivers/s390/cio/vfio_ccw_drv.c | 12 +++++++++++- > >> drivers/s390/cio/vfio_ccw_fsm.c | 6 +++--- > >> drivers/s390/cio/vfio_ccw_ops.c | 4 ++-- > >> drivers/s390/cio/vfio_ccw_private.h | 2 +- > >> 4 files changed, 17 insertions(+), 7 deletions(-) > >> > > > >> @@ -114,6 +114,14 @@ static int vfio_ccw_sch_probe(struct subchannel *sch) > >> private = kzalloc(sizeof(*private), GFP_KERNEL | GFP_DMA); > >> if (!private) > >> return -ENOMEM; > >> + > >> + private->io_region = kzalloc(sizeof(*private->io_region), > >> + GFP_KERNEL | GFP_DMA); > > > > Any particular reason for this to be under 2G? Looking through the > > code, I did not spot a place where we feed things in there directly to > > an interface that is 2G sensitive. > > > > I'm inclined to just keep it for now (as the structure it was taken > > from was also allocated below 2G), but this might be a remainder of the > > original implementation that was not using idals (and we might be able > > to get rid of GFP_DMA here). > > I suspect you are right and it can be removed, since I don't see any > reason it needs to be. But I don't know the history here, so I just > kept the same allocation. I guess it makes sense to look into that > cleanup here. But I did say this was a quick attempt. :) Yes, it makes sense to just keep the flags for now. We can still change it easily on top.
