Message ID | 20190222021927.13132-8-baolu.lu@linux.intel.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | vfio/mdev: IOMMU aware mediated device | expand |
On Fri, Feb 22, 2019 at 10:19:25AM +0800, Lu Baolu wrote: > A parent device might create different types of mediated > devices. For example, a mediated device could be created > by the parent device with full isolation and protection > provided by the IOMMU. One usage case could be found on > Intel platforms where a mediated device is an assignable > subset of a PCI, the DMA requests on behalf of it are all > tagged with a PASID. Since IOMMU supports PASID-granular > translations (scalable mode in VT-d 3.0), this mediated > device could be individually protected and isolated by an > IOMMU. > > This patch adds a new member in the struct mdev_device to > indicate that the mediated device represented by mdev could > be isolated and protected by attaching a domain to a device > represented by mdev->iommu_device. It also adds a helper to > add or set the iommu device. > > * mdev_device->iommu_device > - This, if set, indicates that the mediated device could > be fully isolated and protected by IOMMU via attaching > an iommu domain to this device. If empty, it indicates > using vendor defined isolation, hence bypass IOMMU. > > * mdev_set/get_iommu_device(dev, iommu_device) > - Set or get the iommu device which represents this mdev > in IOMMU's device scope. Drivers don't need to set the > iommu device if it uses vendor defined isolation. > > Cc: Ashok Raj <ashok.raj@intel.com> > Cc: Jacob Pan <jacob.jun.pan@linux.intel.com> > Cc: Kevin Tian <kevin.tian@intel.com> > Cc: Liu Yi L <yi.l.liu@intel.com> > Suggested-by: Kevin Tian <kevin.tian@intel.com> > Suggested-by: Alex Williamson <alex.williamson@redhat.com> > Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> > Reviewed-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> > --- > drivers/vfio/mdev/mdev_core.c | 18 ++++++++++++++++++ > drivers/vfio/mdev/mdev_private.h | 1 + > include/linux/mdev.h | 14 ++++++++++++++ > 3 files changed, 33 insertions(+) > > diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c > index 0212f0ee8aea..9be58d392d2b 100644 > --- a/drivers/vfio/mdev/mdev_core.c > +++ b/drivers/vfio/mdev/mdev_core.c > @@ -390,6 +390,24 @@ int mdev_device_remove(struct device *dev, bool force_remove) > return 0; > } > > +int mdev_set_iommu_device(struct device *dev, struct device *iommu_device) > +{ > + struct mdev_device *mdev = to_mdev_device(dev); > + > + mdev->iommu_device = iommu_device; > + > + return 0; > +} > +EXPORT_SYMBOL(mdev_set_iommu_device); As said before, please make all new mdev/vfio exports EXPORT_SYMBOL_GPL to fit the other exports in vfio.
On Fri, 22 Feb 2019 06:34:38 -0800 Christoph Hellwig <hch@infradead.org> wrote: > On Fri, Feb 22, 2019 at 10:19:25AM +0800, Lu Baolu wrote: > > A parent device might create different types of mediated > > devices. For example, a mediated device could be created > > by the parent device with full isolation and protection > > provided by the IOMMU. One usage case could be found on > > Intel platforms where a mediated device is an assignable > > subset of a PCI, the DMA requests on behalf of it are all > > tagged with a PASID. Since IOMMU supports PASID-granular > > translations (scalable mode in VT-d 3.0), this mediated > > device could be individually protected and isolated by an > > IOMMU. > > > > This patch adds a new member in the struct mdev_device to > > indicate that the mediated device represented by mdev could > > be isolated and protected by attaching a domain to a device > > represented by mdev->iommu_device. It also adds a helper to > > add or set the iommu device. > > > > * mdev_device->iommu_device > > - This, if set, indicates that the mediated device could > > be fully isolated and protected by IOMMU via attaching > > an iommu domain to this device. If empty, it indicates > > using vendor defined isolation, hence bypass IOMMU. > > > > * mdev_set/get_iommu_device(dev, iommu_device) > > - Set or get the iommu device which represents this mdev > > in IOMMU's device scope. Drivers don't need to set the > > iommu device if it uses vendor defined isolation. > > > > Cc: Ashok Raj <ashok.raj@intel.com> > > Cc: Jacob Pan <jacob.jun.pan@linux.intel.com> > > Cc: Kevin Tian <kevin.tian@intel.com> > > Cc: Liu Yi L <yi.l.liu@intel.com> > > Suggested-by: Kevin Tian <kevin.tian@intel.com> > > Suggested-by: Alex Williamson <alex.williamson@redhat.com> > > Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> > > Reviewed-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> > > --- > > drivers/vfio/mdev/mdev_core.c | 18 ++++++++++++++++++ > > drivers/vfio/mdev/mdev_private.h | 1 + > > include/linux/mdev.h | 14 ++++++++++++++ > > 3 files changed, 33 insertions(+) > > > > diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c > > index 0212f0ee8aea..9be58d392d2b 100644 > > --- a/drivers/vfio/mdev/mdev_core.c > > +++ b/drivers/vfio/mdev/mdev_core.c > > @@ -390,6 +390,24 @@ int mdev_device_remove(struct device *dev, bool force_remove) > > return 0; > > } > > > > +int mdev_set_iommu_device(struct device *dev, struct device *iommu_device) > > +{ > > + struct mdev_device *mdev = to_mdev_device(dev); > > + > > + mdev->iommu_device = iommu_device; > > + > > + return 0; > > +} > > +EXPORT_SYMBOL(mdev_set_iommu_device); > > As said before, please make all new mdev/vfio exports EXPORT_SYMBOL_GPL > to fit the other exports in vfio. Well... $ grep EXPORT_SYMBOL drivers/vfio/mdev/* drivers/vfio/mdev/mdev_core.c:EXPORT_SYMBOL(mdev_parent_dev); drivers/vfio/mdev/mdev_core.c:EXPORT_SYMBOL(mdev_get_drvdata); drivers/vfio/mdev/mdev_core.c:EXPORT_SYMBOL(mdev_set_drvdata); drivers/vfio/mdev/mdev_core.c:EXPORT_SYMBOL(mdev_dev); drivers/vfio/mdev/mdev_core.c:EXPORT_SYMBOL(mdev_from_dev); drivers/vfio/mdev/mdev_core.c:EXPORT_SYMBOL(mdev_uuid); drivers/vfio/mdev/mdev_core.c:EXPORT_SYMBOL(mdev_register_device); drivers/vfio/mdev/mdev_core.c:EXPORT_SYMBOL(mdev_unregister_device); drivers/vfio/mdev/mdev_driver.c:EXPORT_SYMBOL_GPL(mdev_bus_type); drivers/vfio/mdev/mdev_driver.c:EXPORT_SYMBOL(mdev_register_driver); drivers/vfio/mdev/mdev_driver.c:EXPORT_SYMBOL(mdev_unregister_driver); For better or worse, the mdev interface does allow non-GPL vendor drivers. This export seems consistent with that, it's a simple association allowing the vendor driver to define an IOMMU API backing device for an mdev device. I don't think this association implies sufficient operational knowledge to require a GPL symbol and it's been requested for use by one of those non-GPL mdev vendor drivers, therefore I support this definition. Thanks, Alex
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c index 0212f0ee8aea..9be58d392d2b 100644 --- a/drivers/vfio/mdev/mdev_core.c +++ b/drivers/vfio/mdev/mdev_core.c @@ -390,6 +390,24 @@ int mdev_device_remove(struct device *dev, bool force_remove) return 0; } +int mdev_set_iommu_device(struct device *dev, struct device *iommu_device) +{ + struct mdev_device *mdev = to_mdev_device(dev); + + mdev->iommu_device = iommu_device; + + return 0; +} +EXPORT_SYMBOL(mdev_set_iommu_device); + +struct device *mdev_get_iommu_device(struct device *dev) +{ + struct mdev_device *mdev = to_mdev_device(dev); + + return mdev->iommu_device; +} +EXPORT_SYMBOL(mdev_get_iommu_device); + static int __init mdev_init(void) { return mdev_bus_register(); diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h index b5819b7d7ef7..891841862ef8 100644 --- a/drivers/vfio/mdev/mdev_private.h +++ b/drivers/vfio/mdev/mdev_private.h @@ -34,6 +34,7 @@ struct mdev_device { struct list_head next; struct kobject *type_kobj; bool active; + struct device *iommu_device; }; #define to_mdev_device(dev) container_of(dev, struct mdev_device, dev) diff --git a/include/linux/mdev.h b/include/linux/mdev.h index b6e048e1045f..c3ab8a9cfcc7 100644 --- a/include/linux/mdev.h +++ b/include/linux/mdev.h @@ -15,6 +15,20 @@ struct mdev_device; +/* + * Called by the parent device driver to set the device which represents + * this mdev in iommu protection scope. By default, the iommu device is + * NULL, that indicates using vendor defined isolation. + * + * @dev: the mediated device that iommu will isolate. + * @iommu_device: a pci device which represents the iommu for @dev. + * + * Return 0 for success, otherwise negative error value. + */ +int mdev_set_iommu_device(struct device *dev, struct device *iommu_device); + +struct device *mdev_get_iommu_device(struct device *dev); + /** * struct mdev_parent_ops - Structure to be registered for each parent device to * register the device to mdev module.