dmaengine.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jacob Pan <jacob.jun.pan@linux.intel.com>
To: Jason Gunthorpe <jgg@nvidia.com>
Cc: "Tian, Kevin" <kevin.tian@intel.com>,
	Baolu Lu <baolu.lu@linux.intel.com>,
	LKML <linux-kernel@vger.kernel.org>,
	"iommu@lists.linux.dev" <iommu@lists.linux.dev>,
	Joerg Roedel <joro@8bytes.org>,
	"dmaengine@vger.kernel.org" <dmaengine@vger.kernel.org>,
	"vkoul@kernel.org" <vkoul@kernel.org>,
	Robin Murphy <robin.murphy@arm.com>,
	Will Deacon <will@kernel.org>,
	David Woodhouse <dwmw2@infradead.org>,
	"Raj, Ashok" <ashok.raj@intel.com>,
	"Liu, Yi L" <yi.l.liu@intel.com>,
	"Yu, Fenghua" <fenghua.yu@intel.com>,
	"Jiang, Dave" <dave.jiang@intel.com>,
	"Luck, Tony" <tony.luck@intel.com>,
	"Zanussi, Tom" <tom.zanussi@intel.com>,
	jacob.jun.pan@linux.intel.com
Subject: Re: [PATCH v2 7/8] iommu: Export iommu_get_dma_domain
Date: Tue, 28 Mar 2023 10:25:40 -0700	[thread overview]
Message-ID: <20230328102540.6158e642@jacob-builder> (raw)
In-Reply-To: <ZCMTf5RwebmELsoT@nvidia.com>

Hi Jason,

On Tue, 28 Mar 2023 13:19:11 -0300, Jason Gunthorpe <jgg@nvidia.com> wrote:

> On Tue, Mar 28, 2023 at 08:48:22AM -0700, Jacob Pan wrote:
> 
> > > Agree. The kernel driver managing the device wants to get the current 
> > > domain of the device then iommu_get_domain_for_dev() is the right
> > > interface. It knows the domain is the dma domain.  
> > This goes back to v1 then :)
> > 
> > I thought the comments from v1 is that we don't want to check the domain
> > type is DMA domain returned by iommu_get_domain_for_dev()
> > 
> > If the driver "knows" the domain is dma domain, why can't it use
> > iommu_get_dma_domain()? seems paradoxical.  
> 
> Huh?
> 
> The DMA API operates on the current domain of the device, be it
> IDENTITY or UNMANAGED.
> 
> You have to copy whatever the current domain is to the PASID and you
> should definately not check if it is DMA or something.
> 
right, the PASID works for IOVA, passthrough. I misunderstood the v1
review comments. I will go back to use iommu_get_domain_for_dev() but w/o
checking domain types.

Thanks all,

Jacob

  reply	other threads:[~2023-03-28 17:21 UTC|newest]

Thread overview: 39+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-27 23:21 [PATCH v2 0/8] Re-enable IDXD kernel workqueue under DMA API Jacob Pan
2023-03-27 23:21 ` [PATCH v2 1/8] iommu/vt-d: Use non-privileged mode for all PASIDs Jacob Pan
2023-03-28  4:55   ` Baolu Lu
2023-03-27 23:21 ` [PATCH v2 2/8] iommu/vt-d: Remove PASID supervisor request support Jacob Pan
2023-03-28  4:59   ` Baolu Lu
2023-03-27 23:21 ` [PATCH v2 3/8] iommu/sva: Support reservation of global SVA PASIDs Jacob Pan
2023-03-28  5:11   ` Baolu Lu
2023-03-28 15:21     ` Jacob Pan
2023-03-28  7:35   ` Tian, Kevin
2023-03-28 15:31     ` Jacob Pan
2023-03-28 15:55       ` Jason Gunthorpe
2023-03-28 16:32         ` Jacob Pan
2023-03-27 23:21 ` [PATCH v2 4/8] iommu/vt-d: Reserve RID_PASID from global SVA PASID space Jacob Pan
2023-03-28  5:20   ` Baolu Lu
2023-03-28 16:29     ` Jacob Pan
2023-03-28 20:52       ` Jacob Pan
2023-03-29  6:13         ` Baolu Lu
2023-03-29  8:20     ` Vasant Hegde
2023-03-27 23:21 ` [PATCH v2 5/8] iommu/vt-d: Make device pasid attachment explicit Jacob Pan
2023-03-28  5:49   ` Baolu Lu
2023-03-28  7:44     ` Tian, Kevin
2023-03-28 20:39       ` Jacob Pan
2023-03-29  6:18       ` Baolu Lu
2023-03-27 23:21 ` [PATCH v2 6/8] iommu/vt-d: Implement set_dev_pasid domain op Jacob Pan
2023-03-28  7:47   ` Tian, Kevin
2023-03-28 15:40     ` Jacob Pan
2023-03-29  3:04       ` Tian, Kevin
2023-03-29  6:22       ` Baolu Lu
2023-03-27 23:21 ` [PATCH v2 7/8] iommu: Export iommu_get_dma_domain Jacob Pan
2023-03-28  6:04   ` Baolu Lu
2023-03-28  7:52     ` Tian, Kevin
2023-03-28 15:48       ` Jacob Pan
2023-03-28 16:19         ` Jason Gunthorpe
2023-03-28 17:25           ` Jacob Pan [this message]
2023-03-28 15:48     ` Jacob Pan
2023-03-29  6:28       ` Baolu Lu
2023-03-27 23:21 ` [PATCH v2 8/8] dmaengine/idxd: Re-enable kernel workqueue under DMA API Jacob Pan
2023-03-28 18:16   ` Fenghua Yu
2023-03-28 20:23     ` Jacob Pan

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=20230328102540.6158e642@jacob-builder \
    --to=jacob.jun.pan@linux.intel.com \
    --cc=ashok.raj@intel.com \
    --cc=baolu.lu@linux.intel.com \
    --cc=dave.jiang@intel.com \
    --cc=dmaengine@vger.kernel.org \
    --cc=dwmw2@infradead.org \
    --cc=fenghua.yu@intel.com \
    --cc=iommu@lists.linux.dev \
    --cc=jgg@nvidia.com \
    --cc=joro@8bytes.org \
    --cc=kevin.tian@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=robin.murphy@arm.com \
    --cc=tom.zanussi@intel.com \
    --cc=tony.luck@intel.com \
    --cc=vkoul@kernel.org \
    --cc=will@kernel.org \
    --cc=yi.l.liu@intel.com \
    /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).