On 2022/3/15 19:49, Tian, Kevin wrote:
From: Jean-Philippe Brucker<jean-phili...@linaro.org>
Sent: Tuesday, March 15, 2022 7:27 PM
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.
iiuc this API can also work for future SIOV usage where each mdev attached
to the domain has its own pasid. "assigning a PASID to a domain" sounds
like going back to the previous aux domain approach which has one PASID
per domain and that PASID is used on all devices attached to the aux domain...
This also works for SVA as far as I can see. The sva_bind essentially is
to attach an SVA domain to the PASID of a device. The sva_bind/unbind
ops could be removed with these two new callbacks.
Best regards,
baolu
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
