On Mon, 2024-04-29 at 10:31 -0600, Alex Williamson wrote:
> On Thu, 25 Apr 2024 18:56:03 +0200
> Gerd Bayer <gbayer@xxxxxxxxxxxxx> wrote:
>
> > From: Ben Segal <bpsegal@xxxxxxxxxx>
> >
> > Many PCI adapters can benefit or even require full 64bit read
> > and write access to their registers. In order to enable work on
> > user-space drivers for these devices add two new variations
> > vfio_pci_core_io{read|write}64 of the existing access methods
> > when the architecture supports 64-bit ioreads and iowrites.
> >
> > Signed-off-by: Ben Segal <bpsegal@xxxxxxxxxx>
> > Co-developed-by: Gerd Bayer <gbayer@xxxxxxxxxxxxx>
> > Signed-off-by: Gerd Bayer <gbayer@xxxxxxxxxxxxx>
> > ---
> > drivers/vfio/pci/vfio_pci_rdwr.c | 16 ++++++++++++++++
> > include/linux/vfio_pci_core.h | 3 +++
> > 2 files changed, 19 insertions(+)
> >
> > diff --git a/drivers/vfio/pci/vfio_pci_rdwr.c
> > b/drivers/vfio/pci/vfio_pci_rdwr.c
> > index 3335f1b868b1..8ed06edaee23 100644
> > --- a/drivers/vfio/pci/vfio_pci_rdwr.c
> > +++ b/drivers/vfio/pci/vfio_pci_rdwr.c
> > @@ -89,6 +89,9 @@ EXPORT_SYMBOL_GPL(vfio_pci_core_ioread##size);
> > VFIO_IOREAD(8)
> > VFIO_IOREAD(16)
> > VFIO_IOREAD(32)
> > +#ifdef ioread64
> > +VFIO_IOREAD(64)
> > +#endif
> >
> > #define
> > VFIO_IORDWR(size) \
> > static int vfio_pci_core_iordwr##size(struct vfio_pci_core_device
> > *vdev,\
> > @@ -124,6 +127,10 @@ static int vfio_pci_core_iordwr##size(struct
> > vfio_pci_core_device *vdev,\
> > VFIO_IORDWR(8)
> > VFIO_IORDWR(16)
> > VFIO_IORDWR(32)
> > +#if defined(ioread64) && defined(iowrite64)
> > +VFIO_IORDWR(64)
> > +#endif
> > +
> > /*
> > * Read or write from an __iomem region (MMIO or I/O port) with an
> > excluded
> > * range which is inaccessible. The excluded range drops writes
> > and fills
> > @@ -148,6 +155,15 @@ ssize_t vfio_pci_core_do_io_rw(struct
> > vfio_pci_core_device *vdev, bool test_mem,
> > else
> > fillable = 0;
> >
> > +#if defined(ioread64) && defined(iowrite64)
>
> Nit, #ifdef vfio_pci_core_iordwr64
I'm sorry, but I'm not sure how I should check for the expanded symbol
here. I think I'll have to stick to checking the same condition as for
whether VFIO_IORDWR(64) should be expanded.
> > + if (fillable >= 8 && !(off % 8)) {
> > + ret = vfio_pci_core_iordwr64(vdev,
> > iswrite, test_mem,
> > + io, buf, off,
> > &filled);
> > + if (ret)
> > + return ret;
> > +
> > + } else
> > +#endif /* defined(ioread64) && defined(iowrite64) */
>
> AFAIK, the comment appended to the #endif is really only suggested
> when the code block is too long to reasonable fit in a terminal.
> That's no longer the case with the new helper.
Yes, I'll change that.
> Thanks,
>
> Alex
>
>
Thanks, Gerd
