On 2026-07-16 02:03 PM, Jason Gunthorpe wrote: > Add a region_size field to struct vfio_pci_driver_ops so drivers can > declare how much DMA-mapped region they need. The mlx5 driver will need > ~18MB for firmware pages. Existing drivers pass in the sizeof their state > struct. The core code will round up and minimize it to SZ_2M so as not to > change any test behavior.
Please update this last sentence to match the patch. > > Assisted-by: Claude:claude-opus-4.6 > Signed-off-by: Jason Gunthorpe <[email protected]> > --- > tools/testing/selftests/vfio/lib/drivers/dsa/dsa.c | 1 + > tools/testing/selftests/vfio/lib/drivers/ioat/ioat.c | 1 + > .../selftests/vfio/lib/include/libvfio/vfio_pci_driver.h | 6 ++++++ > tools/testing/selftests/vfio/lib/vfio_pci_driver.c | 7 +++++++ > tools/testing/selftests/vfio/vfio_pci_driver_test.c | 3 ++- > 5 files changed, 17 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/vfio/lib/drivers/dsa/dsa.c > b/tools/testing/selftests/vfio/lib/drivers/dsa/dsa.c > index 19d9630b24c23f..40b8541b588eee 100644 > --- a/tools/testing/selftests/vfio/lib/drivers/dsa/dsa.c > +++ b/tools/testing/selftests/vfio/lib/drivers/dsa/dsa.c > @@ -418,6 +418,7 @@ static void dsa_send_msi(struct vfio_pci_device *device) > > const struct vfio_pci_driver_ops dsa_ops = { > .name = "dsa", > + .region_size = sizeof(struct dsa_state), > .probe = dsa_probe, > .init = dsa_init, > .remove = dsa_remove, > diff --git a/tools/testing/selftests/vfio/lib/drivers/ioat/ioat.c > b/tools/testing/selftests/vfio/lib/drivers/ioat/ioat.c > index a871b935542bad..c9b28365c5eb6b 100644 > --- a/tools/testing/selftests/vfio/lib/drivers/ioat/ioat.c > +++ b/tools/testing/selftests/vfio/lib/drivers/ioat/ioat.c > @@ -226,6 +226,7 @@ static void ioat_send_msi(struct vfio_pci_device *device) > > const struct vfio_pci_driver_ops ioat_ops = { > .name = "ioat", > + .region_size = sizeof(struct ioat_state), When you rebase on top of vfio/next please also make these changes to the NV Falcon and IGB drivers that have recently landed. > .probe = ioat_probe, > .init = ioat_init, > .remove = ioat_remove, > diff --git > a/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_driver.h > b/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_driver.h > index e5ada209b1d102..547369c5cff95a 100644 > --- a/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_driver.h > +++ b/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_driver.h > @@ -9,6 +9,12 @@ struct vfio_pci_device; > struct vfio_pci_driver_ops { > const char *name; > > + /* > + * Size of the driver's state structure overlaid on > + * device->driver.region.vaddr > + */ > + u64 region_size; > + > /** > * @probe() - Check if the driver supports the given device. > * > diff --git a/tools/testing/selftests/vfio/lib/vfio_pci_driver.c > b/tools/testing/selftests/vfio/lib/vfio_pci_driver.c > index 6827f4a6febe99..e13bbb7ee423dc 100644 > --- a/tools/testing/selftests/vfio/lib/vfio_pci_driver.c > +++ b/tools/testing/selftests/vfio/lib/vfio_pci_driver.c > @@ -1,5 +1,7 @@ > // SPDX-License-Identifier: GPL-2.0-only > #include "kselftest.h" > +#include <linux/sizes.h> > +#include <linux/log2.h> > #include <libvfio.h> > > #ifdef __x86_64__ > @@ -28,6 +30,11 @@ void vfio_pci_driver_probe(struct vfio_pci_device *device) > continue; > > device->driver.ops = ops; > + > + VFIO_ASSERT_NE(ops->region_size, 0); > + device->driver.region.size = > + max_t(u64, roundup_pow_of_two(ops->region_size), > + getpagesize()); Blegh this is because the IOVA allocator insists on a power-of-2 size as you pointed out [1]. Can you add a comment here to document that? Or better yet, move the rounding up into iova_allocator_alloc() so the callers don't have to deal with it like this. [1] https://lore.kernel.org/all/[email protected]/ > } > } > > diff --git a/tools/testing/selftests/vfio/vfio_pci_driver_test.c > b/tools/testing/selftests/vfio/vfio_pci_driver_test.c > index afa0480ddd9b2a..f68239da574f5a 100644 > --- a/tools/testing/selftests/vfio/vfio_pci_driver_test.c > +++ b/tools/testing/selftests/vfio/vfio_pci_driver_test.c > @@ -80,7 +80,8 @@ FIXTURE_SETUP(vfio_pci_driver_test) > driver = &self->device->driver; > > region_setup(self->iommu, self->iova_allocator, &self->memcpy_region, > SZ_1G); > - region_setup(self->iommu, self->iova_allocator, &driver->region, SZ_2M); > + region_setup(self->iommu, self->iova_allocator, &driver->region, > + driver->region.size); > > /* Any IOVA that doesn't overlap memcpy_region and driver->region. */ > self->unmapped_iova = iova_allocator_alloc(self->iova_allocator, SZ_1G); > -- > 2.43.0 >
