On Mon, Mar 14, 2022 at 10:07:06PM -0700, Jacob Pan wrote: > From: Lu Baolu <baolu...@linux.intel.com> > > An IOMMU domain represents an address space which can be attached by > devices that perform DMA within a domain. However, for platforms with > PASID capability the domain attachment needs be handled at device+PASID > level. There can be multiple PASIDs within a device and multiple devices > attached to a given domain. > This patch introduces a new IOMMU op which support device, PASID, and > IOMMU domain attachment. The immediate use case is for PASID capable > devices to perform DMA under DMA APIs. > > Signed-off-by: Lu Baolu <baolu...@linux.intel.com> > Signed-off-by: Jacob Pan <jacob.jun....@linux.intel.com> > --- > include/linux/iommu.h | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/include/linux/iommu.h b/include/linux/iommu.h > index 369f05c2a4e2..fde5b933dbe3 100644 > --- a/include/linux/iommu.h > +++ b/include/linux/iommu.h > @@ -227,6 +227,8 @@ struct iommu_iotlb_gather { > * @aux_get_pasid: get the pasid given an aux-domain > * @sva_bind: Bind process address space to device > * @sva_unbind: Unbind process address space from device > + * @attach_dev_pasid: attach an iommu domain to a pasid of device > + * @detach_dev_pasid: detach an iommu domain from a pasid of device
Isn't that operation "assign a PASID to a domain" instead? In patch 5, the domain is already attached to the device, so set_domain_pasid() might be clearer and to the point. If the IOMMU driver did the allocation we could also avoid patch 1. If I understand correctly this series is not about a generic PASID API that allows drivers to manage multiple DMA address spaces, because there still doesn't seem to be any interest in that. It's about the specific IDXD use-case, so let's focus on that. We can introduce a specialized call such as (iommu|dma)_set_device_pasid(), which will be easy to consolidate later into a more generic "dma_enable_pasid()" API if that ever seems useful. Thanks, Jean > * @sva_get_pasid: Get PASID associated to a SVA handle > * @page_response: handle page request response > * @cache_invalidate: invalidate translation caches > @@ -296,6 +298,10 @@ struct iommu_ops { > struct iommu_sva *(*sva_bind)(struct device *dev, struct mm_struct *mm, > void *drvdata); > void (*sva_unbind)(struct iommu_sva *handle); > + int (*attach_dev_pasid)(struct iommu_domain *domain, > + struct device *dev, ioasid_t id); > + void (*detach_dev_pasid)(struct iommu_domain *domain, > + struct device *dev, ioasid_t id); > u32 (*sva_get_pasid)(struct iommu_sva *handle); > > int (*page_response)(struct device *dev, > -- > 2.25.1 > _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu