Re: [PATCH v9 0/7] Re-enable IDXD kernel workqueue under DMA API

From: Jacob Pan
Date: Mon Jul 10 2023 - 13:13:23 EST


Hi Baolu, Joerg, and all,

Just wondering if there are more comments?

Thanks,

Jacob

On Wed, 21 Jun 2023 13:59:40 -0700, Jacob Pan
<jacob.jun.pan@xxxxxxxxxxxxxxx> wrote:

> Hi Joerg and all,
>
> IDXD kernel work queues were disabled due to the flawed use of kernel VA
> and SVA API.
> Link:
> https://lore.kernel.org/linux-iommu/20210511194726.GP1002214@xxxxxxxxxx/
>
> The solution is to enable it under DMA API where IDXD shared workqueue
> users can use ENQCMDS to submit work on buffers mapped by DMA API.
>
> This patchset adds support for attaching PASID to the device's default
> domain and the ability to allocate global PASIDs from IOMMU APIs. IDXD
> driver can then re-enable the kernel work queues and use them under DMA
> API.
>
> This depends on the IOASID removal series. (merged)
> https://lore.kernel.org/all/ZCaUBJvUMsJyD7EW@xxxxxxxxxx/
>
>
> Thanks,
>
> Jacob
>
> ---
> Changelog:
> v9:
> - Fix an IDXD driver issue where user interrupt enable bit got
> cleared during device enable/disable cycle. Reported and tested by
> Tony Zhu <tony.zhu@xxxxxxxxx>
> - Rebased to v6.4-rc7
> v8:
> - further vt-d driver refactoring (3-6) around set/remove device
> PASID (Baolu)
> - make consistent use of NO_PASID in SMMU code (Jean)
> - fix off-by-one error in max PASID check (Kevin)
> v7:
> - renamed IOMMU_DEF_RID_PASID to be IOMMU_NO_PASID to be more
> generic (Jean)
> - simplify range checking for sva PASID (Baolu)
> v6:
> - use a simplified version of vt-d driver change for
> set_device_pasid from Baolu.
> - check and rename global PASID allocation base
> v5:
> - exclude two patches related to supervisor mode, taken by VT-d
> maintainer Baolu.
> - move PASID range check into allocation API so that device
> drivers only need to pass in struct device*. (Kevin)
> - factor out helper functions in device-domain attach (Baolu)
> - make explicit use of RID_PASID across architectures
> v4:
> - move dummy functions outside ifdef CONFIG_IOMMU_SVA (Baolu)
> - dropped domain type check while disabling idxd system PASID
> (Baolu)
>
> v3:
> - moved global PASID allocation API from SVA to IOMMU (Kevin)
> - remove #ifdef around global PASID reservation during boot
> (Baolu)
> - remove restriction on PASID 0 allocation (Baolu)
> - fix a bug in sysfs domain change when attaching devices
> - clear idxd user interrupt enable bit after disabling device(
> Fenghua) v2:
> - refactored device PASID attach domain ops based on Baolu's
> early patch
> - addressed TLB flush gap
> - explicitly reserve RID_PASID from SVA PASID number space
> - get dma domain directly, avoid checking domain types
>
> Jacob Pan (3):
> iommu: Generalize PASID 0 for normal DMA w/o PASID
> iommu: Move global PASID allocation from SVA to core
> dmaengine/idxd: Re-enable kernel workqueue under DMA API
>
> Lu Baolu (4):
> iommu/vt-d: Add domain_flush_pasid_iotlb()
> iommu/vt-d: Remove pasid_mutex
> iommu/vt-d: Make prq draining code generic
> iommu/vt-d: Add set_dev_pasid callback for dma domain
>
> drivers/dma/idxd/device.c | 39 ++---
> drivers/dma/idxd/dma.c | 5 +-
> drivers/dma/idxd/idxd.h | 9 +
> drivers/dma/idxd/init.c | 54 +++++-
> drivers/dma/idxd/sysfs.c | 7 -
> .../iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 2 +-
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 16 +-
> drivers/iommu/intel/iommu.c | 161 +++++++++++++++---
> drivers/iommu/intel/iommu.h | 9 +
> drivers/iommu/intel/pasid.c | 2 +-
> drivers/iommu/intel/pasid.h | 2 -
> drivers/iommu/intel/svm.c | 53 +-----
> drivers/iommu/iommu-sva.c | 28 ++-
> drivers/iommu/iommu.c | 28 +++
> include/linux/iommu.h | 11 ++
> 15 files changed, 291 insertions(+), 135 deletions(-)
>


Thanks,

Jacob