iommu.lists.linux-foundation.org archive mirror
 help / color / mirror / Atom feed
From: Baolu Lu <baolu.lu@linux.intel.com>
To: "Tian, Kevin" <kevin.tian@intel.com>,
	Jean-Philippe Brucker <jean-philippe@linaro.org>
Cc: "Jiang, Dave" <dave.jiang@intel.com>,
	"Raj, Ashok" <ashok.raj@intel.com>,
	"iommu@lists.linux.dev" <iommu@lists.linux.dev>,
	Robin Murphy <robin.murphy@arm.com>,
	"iommu@lists.linux-foundation.org"
	<iommu@lists.linux-foundation.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Christoph Hellwig <hch@infradead.org>,
	Jean-Philippe Brucker <jean-philippe@linaro.com>,
	Vinod Koul <vkoul@kernel.org>,
	"Pan, Jacob jun" <jacob.jun.pan@intel.com>,
	Jason Gunthorpe <jgg@nvidia.com>, Will Deacon <will@kernel.org>
Subject: Re: [PATCH v9 10/11] iommu: Per-domain I/O page fault handling
Date: Tue, 28 Jun 2022 20:18:16 +0800	[thread overview]
Message-ID: <826513b6-15d3-902d-03c2-7f7e68a84095@linux.intel.com> (raw)
In-Reply-To: <BN9PR11MB527605AA0663E8BE592898FE8CB89@BN9PR11MB5276.namprd11.prod.outlook.com>

On 2022/6/28 18:02, Tian, Kevin wrote:
>> From: Jean-Philippe Brucker <jean-philippe@linaro.org>
>> Sent: Tuesday, June 28, 2022 5:44 PM
>>
>> On Tue, Jun 28, 2022 at 08:39:36AM +0000, Tian, Kevin wrote:
>>>> From: Lu Baolu <baolu.lu@linux.intel.com>
>>>> Sent: Tuesday, June 21, 2022 10:44 PM
>>>>
>>>> Tweak the I/O page fault handling framework to route the page faults to
>>>> the domain and call the page fault handler retrieved from the domain.
>>>> This makes the I/O page fault handling framework possible to serve more
>>>> usage scenarios as long as they have an IOMMU domain and install a
>> page
>>>> fault handler in it. Some unused functions are also removed to avoid
>>>> dead code.
>>>>
>>>> The iommu_get_domain_for_dev_pasid() which retrieves attached
>> domain
>>>> for a {device, PASID} pair is used. It will be used by the page fault
>>>> handling framework which knows {device, PASID} reported from the
>> iommu
>>>> driver. We have a guarantee that the SVA domain doesn't go away during
>>>> IOPF handling, because unbind() waits for pending faults with
>>>> iopf_queue_flush_dev() before freeing the domain. Hence, there's no
>> need
>>>> to synchronize life cycle of the iommu domains between the unbind() and
>>>> the interrupt threads.
>>>
>>> I found iopf_queue_flush_dev() is only called in intel-iommu driver. Did
>>> I overlook anything?
>>
>> The SMMU driver will need it as well when we upstream PRI support.
>> Currently it only supports stall, and that requires the device driver to
>> flush all DMA including stalled transactions *before* calling unbind(), so
>> ne need for iopf_queue_flush_dev() in this case.
>>
> 
> then it makes sense. Probably Baolu can add this information in the
> commit msg so others with similar question can quickly get the
> point here.

Sure. Updated.

Best regards,
baolu
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

WARNING: multiple messages have this Message-ID (diff)
From: Baolu Lu <baolu.lu@linux.intel.com>
To: "Tian, Kevin" <kevin.tian@intel.com>,
	Jean-Philippe Brucker <jean-philippe@linaro.org>
Cc: baolu.lu@linux.intel.com, Joerg Roedel <joro@8bytes.org>,
	Jason Gunthorpe <jgg@nvidia.com>,
	Christoph Hellwig <hch@infradead.org>,
	"Raj, Ashok" <ashok.raj@intel.com>, Will Deacon <will@kernel.org>,
	Robin Murphy <robin.murphy@arm.com>,
	Jean-Philippe Brucker <jean-philippe@linaro.com>,
	"Jiang, Dave" <dave.jiang@intel.com>,
	Vinod Koul <vkoul@kernel.org>, Eric Auger <eric.auger@redhat.com>,
	"Liu, Yi L" <yi.l.liu@intel.com>,
	"Pan, Jacob jun" <jacob.jun.pan@intel.com>,
	"iommu@lists.linux-foundation.org"
	<iommu@lists.linux-foundation.org>,
	"iommu@lists.linux.dev" <iommu@lists.linux.dev>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v9 10/11] iommu: Per-domain I/O page fault handling
Date: Tue, 28 Jun 2022 20:18:16 +0800	[thread overview]
Message-ID: <826513b6-15d3-902d-03c2-7f7e68a84095@linux.intel.com> (raw)
Message-ID: <20220628121816.lYbltpMnr7gwOVlAZ404zprRFFn9f9hsdNlTbYPDDb8@z> (raw)
In-Reply-To: <BN9PR11MB527605AA0663E8BE592898FE8CB89@BN9PR11MB5276.namprd11.prod.outlook.com>

On 2022/6/28 18:02, Tian, Kevin wrote:
>> From: Jean-Philippe Brucker <jean-philippe@linaro.org>
>> Sent: Tuesday, June 28, 2022 5:44 PM
>>
>> On Tue, Jun 28, 2022 at 08:39:36AM +0000, Tian, Kevin wrote:
>>>> From: Lu Baolu <baolu.lu@linux.intel.com>
>>>> Sent: Tuesday, June 21, 2022 10:44 PM
>>>>
>>>> Tweak the I/O page fault handling framework to route the page faults to
>>>> the domain and call the page fault handler retrieved from the domain.
>>>> This makes the I/O page fault handling framework possible to serve more
>>>> usage scenarios as long as they have an IOMMU domain and install a
>> page
>>>> fault handler in it. Some unused functions are also removed to avoid
>>>> dead code.
>>>>
>>>> The iommu_get_domain_for_dev_pasid() which retrieves attached
>> domain
>>>> for a {device, PASID} pair is used. It will be used by the page fault
>>>> handling framework which knows {device, PASID} reported from the
>> iommu
>>>> driver. We have a guarantee that the SVA domain doesn't go away during
>>>> IOPF handling, because unbind() waits for pending faults with
>>>> iopf_queue_flush_dev() before freeing the domain. Hence, there's no
>> need
>>>> to synchronize life cycle of the iommu domains between the unbind() and
>>>> the interrupt threads.
>>>
>>> I found iopf_queue_flush_dev() is only called in intel-iommu driver. Did
>>> I overlook anything?
>>
>> The SMMU driver will need it as well when we upstream PRI support.
>> Currently it only supports stall, and that requires the device driver to
>> flush all DMA including stalled transactions *before* calling unbind(), so
>> ne need for iopf_queue_flush_dev() in this case.
>>
> 
> then it makes sense. Probably Baolu can add this information in the
> commit msg so others with similar question can quickly get the
> point here.

Sure. Updated.

Best regards,
baolu

  parent reply	other threads:[~2022-06-28 12:18 UTC|newest]

Thread overview: 90+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-06-21 14:43 [PATCH v9 00/11] iommu: SVA and IOPF refactoring Lu Baolu
2022-06-21 14:43 ` Lu Baolu
2022-06-21 14:43 ` [PATCH v9 01/11] iommu: Add max_pasids field in struct iommu_device Lu Baolu
2022-06-21 14:43   ` Lu Baolu
2022-06-27  8:05   ` Tian, Kevin
2022-06-27  8:05     ` Tian, Kevin
2022-06-21 14:43 ` [PATCH v9 02/11] iommu: Add max_pasids field in struct dev_iommu Lu Baolu
2022-06-21 14:43   ` Lu Baolu
2022-06-27  8:06   ` Tian, Kevin
2022-06-27  8:06     ` Tian, Kevin
2022-06-21 14:43 ` [PATCH v9 03/11] iommu: Remove SVM_FLAG_SUPERVISOR_MODE support Lu Baolu
2022-06-21 14:43   ` Lu Baolu
2022-06-21 14:43 ` [PATCH v9 04/11] iommu: Add sva iommu_domain support Lu Baolu
2022-06-21 14:43   ` Lu Baolu
2022-06-27  8:29   ` Tian, Kevin
2022-06-27  8:29     ` Tian, Kevin
2022-06-28  5:41     ` Baolu Lu
2022-06-28  5:41       ` Baolu Lu
2022-06-28  8:50       ` Tian, Kevin
2022-06-28  8:50         ` Tian, Kevin
2022-06-28 11:33         ` Baolu Lu
2022-06-28 11:33           ` Baolu Lu
2022-06-29  1:54           ` Tian, Kevin
2022-06-29  1:54             ` Tian, Kevin
2022-06-29  4:44             ` Baolu Lu
2022-06-29  4:44               ` Baolu Lu
2022-06-28 11:41         ` Baolu Lu
2022-06-28 11:41           ` Baolu Lu
2022-06-21 14:43 ` [PATCH v9 05/11] iommu/vt-d: Add SVA domain support Lu Baolu
2022-06-21 14:43   ` Lu Baolu
2022-06-27  8:32   ` Tian, Kevin
2022-06-27  8:32     ` Tian, Kevin
2022-06-21 14:43 ` [PATCH v9 06/11] arm-smmu-v3/sva: " Lu Baolu
2022-06-21 14:43   ` Lu Baolu
2022-06-27 11:50   ` Zhangfei Gao
2022-06-27 11:50     ` Zhangfei Gao
2022-06-28  5:46     ` Baolu Lu
2022-06-28  5:46       ` Baolu Lu
2022-06-28  6:13     ` Baolu Lu
2022-06-28  6:13       ` Baolu Lu
2022-06-28  6:17       ` Zhu, Tony
2022-06-28  6:17         ` Zhu, Tony
2022-06-21 14:43 ` [PATCH v9 07/11] iommu/sva: Refactoring iommu_sva_bind/unbind_device() Lu Baolu
2022-06-21 14:43   ` Lu Baolu
2022-06-27 10:14   ` Tian, Kevin
2022-06-27 10:14     ` Tian, Kevin
2022-06-28  5:53     ` Baolu Lu
2022-06-28  5:53       ` Baolu Lu
2022-06-28  8:52       ` Tian, Kevin
2022-06-28  8:52         ` Tian, Kevin
2022-06-21 14:43 ` [PATCH v9 08/11] iommu: Remove SVA related callbacks from iommu ops Lu Baolu
2022-06-21 14:43   ` Lu Baolu
2022-06-21 14:43 ` [PATCH v9 09/11] iommu: Prepare IOMMU domain for IOPF Lu Baolu
2022-06-21 14:43   ` Lu Baolu
2022-06-28  8:29   ` Tian, Kevin
2022-06-28  8:29     ` Tian, Kevin
2022-06-28 10:49     ` Baolu Lu
2022-06-28 10:49       ` Baolu Lu
2022-06-21 14:43 ` [PATCH v9 10/11] iommu: Per-domain I/O page fault handling Lu Baolu
2022-06-21 14:43   ` Lu Baolu
2022-06-27 13:03   ` Ethan Zhao
2022-06-27 13:03     ` Ethan Zhao
2022-06-28  6:28     ` Baolu Lu
2022-06-28  6:28       ` Baolu Lu
2022-06-28  9:10       ` Ethan Zhao
2022-06-28  9:10         ` Ethan Zhao
2022-06-28 11:53         ` Baolu Lu
2022-06-28 11:53           ` Baolu Lu
2022-06-28 14:20           ` Jean-Philippe Brucker
2022-06-28 14:20             ` Jean-Philippe Brucker
2022-06-29  0:24             ` Baolu Lu
2022-06-29  0:24               ` Baolu Lu
2022-06-29  6:15             ` Ethan Zhao
2022-06-29  6:15               ` Ethan Zhao
2022-06-28  8:39   ` Tian, Kevin
2022-06-28  8:39     ` Tian, Kevin
2022-06-28  9:44     ` Jean-Philippe Brucker
2022-06-28  9:44       ` Jean-Philippe Brucker
2022-06-28 10:02       ` Tian, Kevin
2022-06-28 10:02         ` Tian, Kevin
2022-06-28 12:18         ` Baolu Lu [this message]
2022-06-28 12:18           ` Baolu Lu
2022-06-28 11:02     ` Baolu Lu
2022-06-28 11:02       ` Baolu Lu
2022-06-21 14:43 ` [PATCH v9 11/11] iommu: Rename iommu-sva-lib.{c,h} Lu Baolu
2022-06-21 14:43   ` Lu Baolu
2022-06-28  8:40   ` Tian, Kevin
2022-06-28  8:40     ` Tian, Kevin
2022-06-26  1:15 ` [PATCH v9 00/11] iommu: SVA and IOPF refactoring Baolu Lu
2022-06-26  1:15   ` Baolu Lu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=826513b6-15d3-902d-03c2-7f7e68a84095@linux.intel.com \
    --to=baolu.lu@linux.intel.com \
    --cc=ashok.raj@intel.com \
    --cc=dave.jiang@intel.com \
    --cc=hch@infradead.org \
    --cc=iommu@lists.linux-foundation.org \
    --cc=iommu@lists.linux.dev \
    --cc=jacob.jun.pan@intel.com \
    --cc=jean-philippe@linaro.com \
    --cc=jean-philippe@linaro.org \
    --cc=jgg@nvidia.com \
    --cc=kevin.tian@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=robin.murphy@arm.com \
    --cc=vkoul@kernel.org \
    --cc=will@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).