| Message ID | 313a27d92bd63e9571bf0f053eabfc3bfe4bfbae.1737754129.git.nicolinc@nvidia.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | iommufd: Add vIOMMU infrastructure (Part-3: vEVENTQ) | expand |
On Fri, Jan 24, 2025 at 04:30:35PM -0800, Nicolin Chen wrote: > This is a reverse search v.s. iommufd_viommu_find_dev, as drivers may want > to convert a struct device pointer (physical) to its virtual device ID for > an event injection to the user space VM. > > Again, this avoids exposing more core structures to the drivers, than the > iommufd_viommu alone. > > Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> > Reviewed-by: Kevin Tian <kevin.tian@intel.com> > Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> > --- > include/linux/iommufd.h | 9 +++++++++ > drivers/iommu/iommufd/driver.c | 24 ++++++++++++++++++++++++ > 2 files changed, 33 insertions(+) Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> > + xa_lock(&viommu->vdevs); > + xa_for_each(&viommu->vdevs, index, vdev) { > + if (vdev->dev == dev) { > + *vdev_id = (unsigned long)vdev->id; I don't think we need this cast Jason
On Tue, Feb 18, 2025 at 11:31:54AM -0400, Jason Gunthorpe wrote: > On Fri, Jan 24, 2025 at 04:30:35PM -0800, Nicolin Chen wrote: > > This is a reverse search v.s. iommufd_viommu_find_dev, as drivers may want > > to convert a struct device pointer (physical) to its virtual device ID for > > an event injection to the user space VM. > > > > Again, this avoids exposing more core structures to the drivers, than the > > iommufd_viommu alone. > > > > Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> > > Reviewed-by: Kevin Tian <kevin.tian@intel.com> > > Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> > > --- > > include/linux/iommufd.h | 9 +++++++++ > > drivers/iommu/iommufd/driver.c | 24 ++++++++++++++++++++++++ > > 2 files changed, 33 insertions(+) > > Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> > > > + xa_lock(&viommu->vdevs); > > + xa_for_each(&viommu->vdevs, index, vdev) { > > + if (vdev->dev == dev) { > > + *vdev_id = (unsigned long)vdev->id; > > I don't think we need this cast The left side is ulong for xarray index, while the right side is __aligned_u64 for uAPI. Could there be a gcc warning when somebody builds the kernel having a BITS_PER_LONG=32? iommufd_vdevice_alloc_ioctl() does test vdev->id against ULONG_MAX though.. Thanks Nicolin
On Wed, Feb 19, 2025 at 09:17:18PM -0800, Nicolin Chen wrote: > On Tue, Feb 18, 2025 at 11:31:54AM -0400, Jason Gunthorpe wrote: > > On Fri, Jan 24, 2025 at 04:30:35PM -0800, Nicolin Chen wrote: > > > This is a reverse search v.s. iommufd_viommu_find_dev, as drivers may want > > > to convert a struct device pointer (physical) to its virtual device ID for > > > an event injection to the user space VM. > > > > > > Again, this avoids exposing more core structures to the drivers, than the > > > iommufd_viommu alone. > > > > > > Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> > > > Reviewed-by: Kevin Tian <kevin.tian@intel.com> > > > Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> > > > --- > > > include/linux/iommufd.h | 9 +++++++++ > > > drivers/iommu/iommufd/driver.c | 24 ++++++++++++++++++++++++ > > > 2 files changed, 33 insertions(+) > > > > Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> > > > > > + xa_lock(&viommu->vdevs); > > > + xa_for_each(&viommu->vdevs, index, vdev) { > > > + if (vdev->dev == dev) { > > > + *vdev_id = (unsigned long)vdev->id; > > > > I don't think we need this cast > > The left side is ulong for xarray index, while the right side is > __aligned_u64 for uAPI. Could there be a gcc warning when somebody > builds the kernel having a BITS_PER_LONG=32? No. The kernel is full of these implicit casts Jason
diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h index 8948b1836940..05cb393aff0a 100644 --- a/include/linux/iommufd.h +++ b/include/linux/iommufd.h @@ -190,6 +190,8 @@ struct iommufd_object *_iommufd_object_alloc(struct iommufd_ctx *ictx, enum iommufd_object_type type); struct device *iommufd_viommu_find_dev(struct iommufd_viommu *viommu, unsigned long vdev_id); +int iommufd_viommu_get_vdev_id(struct iommufd_viommu *viommu, + struct device *dev, unsigned long *vdev_id); #else /* !CONFIG_IOMMUFD_DRIVER_CORE */ static inline struct iommufd_object * _iommufd_object_alloc(struct iommufd_ctx *ictx, size_t size, @@ -203,6 +205,13 @@ iommufd_viommu_find_dev(struct iommufd_viommu *viommu, unsigned long vdev_id) { return NULL; } + +static inline int iommufd_viommu_get_vdev_id(struct iommufd_viommu *viommu, + struct device *dev, + unsigned long *vdev_id) +{ + return -ENOENT; +} #endif /* CONFIG_IOMMUFD_DRIVER_CORE */ /* diff --git a/drivers/iommu/iommufd/driver.c b/drivers/iommu/iommufd/driver.c index 2d98b04ff1cb..185c4fde8987 100644 --- a/drivers/iommu/iommufd/driver.c +++ b/drivers/iommu/iommufd/driver.c @@ -49,5 +49,29 @@ struct device *iommufd_viommu_find_dev(struct iommufd_viommu *viommu, } EXPORT_SYMBOL_NS_GPL(iommufd_viommu_find_dev, "IOMMUFD"); +/* Return -ENOENT if device is not associated to the vIOMMU */ +int iommufd_viommu_get_vdev_id(struct iommufd_viommu *viommu, + struct device *dev, unsigned long *vdev_id) +{ + struct iommufd_vdevice *vdev; + unsigned long index; + int rc = -ENOENT; + + if (WARN_ON_ONCE(!vdev_id)) + return -EINVAL; + + xa_lock(&viommu->vdevs); + xa_for_each(&viommu->vdevs, index, vdev) { + if (vdev->dev == dev) { + *vdev_id = (unsigned long)vdev->id; + rc = 0; + break; + } + } + xa_unlock(&viommu->vdevs); + return rc; +} +EXPORT_SYMBOL_NS_GPL(iommufd_viommu_get_vdev_id, "IOMMUFD"); + MODULE_DESCRIPTION("iommufd code shared with builtin modules"); MODULE_LICENSE("GPL");