LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Jacob Pan <jacob.jun.pan@linux.intel.com>
To: Alex Williamson <alex.williamson@redhat.com>
Cc: iommu@lists.linux-foundation.org,
	LKML <linux-kernel@vger.kernel.org>,
	Joerg Roedel <joro@8bytes.org>,
	David Woodhouse <dwmw2@infradead.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Jean-Philippe Brucker <jean-philippe.brucker@arm.com>,
	Rafael Wysocki <rafael.j.wysocki@intel.com>,
	"Liu, Yi L" <yi.l.liu@intel.com>,
	"Tian, Kevin" <kevin.tian@intel.com>,
	Raj Ashok <ashok.raj@intel.com>,
	Jean Delvare <khali@linux-fr.org>,
	"Christoph Hellwig" <hch@infradead.org>,
	"Lu Baolu" <baolu.lu@linux.intel.com>,
	Yi L <yi.l.liu@linux.intel.com>,
	jacob.jun.pan@linux.intel.com
Subject: Re: [PATCH v4 04/22] iommu/vt-d: add bind_pasid_table function
Date: Fri, 20 Apr 2018 16:22:59 -0700	[thread overview]
Message-ID: <20180420162259.2d29659a@jacob-builder> (raw)
In-Reply-To: <20180417131047.0a9c310f@w520.home>

On Tue, 17 Apr 2018 13:10:47 -0600
Alex Williamson <alex.williamson@redhat.com> wrote:

> On Mon, 16 Apr 2018 14:48:53 -0700
> Jacob Pan <jacob.jun.pan@linux.intel.com> wrote:
> 
> > Add Intel VT-d ops to the generic iommu_bind_pasid_table API
> > functions.
> > 
> > The primary use case is for direct assignment of SVM capable
> > device. Originated from emulated IOMMU in the guest, the request
> > goes through many layers (e.g. VFIO). Upon calling host IOMMU
> > driver, caller passes guest PASID table pointer (GPA) and size.
> > 
> > Device context table entry is modified by Intel IOMMU specific
> > bind_pasid_table function. This will turn on nesting mode and
> > matching translation type.
> > 
> > The unbind operation restores default context mapping.
> > 
> > Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
> > Signed-off-by: Liu, Yi L <yi.l.liu@linux.intel.com>
> > Signed-off-by: Ashok Raj <ashok.raj@intel.com>
> > ---
> >  drivers/iommu/intel-iommu.c   | 119
> > ++++++++++++++++++++++++++++++++++++++++++
> > include/linux/dma_remapping.h |   1 + 2 files changed, 120
> > insertions(+)
> > 
> > diff --git a/drivers/iommu/intel-iommu.c
> > b/drivers/iommu/intel-iommu.c index a0f81a4..d8058be 100644
> > --- a/drivers/iommu/intel-iommu.c
> > +++ b/drivers/iommu/intel-iommu.c
> > @@ -2409,6 +2409,7 @@ static struct dmar_domain
> > *dmar_insert_one_dev_info(struct intel_iommu *iommu,
> > info->ats_supported = info->pasid_supported = info->pri_supported =
> > 0; info->ats_enabled = info->pasid_enabled = info->pri_enabled = 0;
> > info->ats_qdep = 0;
> > +	info->pasid_table_bound = 0;
> >  	info->dev = dev;
> >  	info->domain = domain;
> >  	info->iommu = iommu;
> > @@ -5132,6 +5133,7 @@ static void
> > intel_iommu_put_resv_regions(struct device *dev, 
> >  #ifdef CONFIG_INTEL_IOMMU_SVM
> >  #define MAX_NR_PASID_BITS (20)
> > +#define MIN_NR_PASID_BITS (5)
> >  static inline unsigned long intel_iommu_get_pts(struct intel_iommu
> > *iommu) {
> >  	/*
> > @@ -5258,6 +5260,119 @@ struct intel_iommu
> > *intel_svm_device_to_iommu(struct device *dev) 
> >  	return iommu;
> >  }
> > +
> > +static int intel_iommu_bind_pasid_table(struct iommu_domain
> > *domain,
> > +		struct device *dev, struct pasid_table_config
> > *pasidt_binfo) +{  
> 
> Never validates pasidt_binfo->{version,bytes}
> 
good catch, will do.
> > +	struct intel_iommu *iommu;
> > +	struct context_entry *context;
> > +	struct dmar_domain *dmar_domain = to_dmar_domain(domain);
> > +	struct device_domain_info *info;
> > +	struct pci_dev *pdev;
> > +	u8 bus, devfn, host_table_pasid_bits;
> > +	u16 did, sid;
> > +	int ret = 0;
> > +	unsigned long flags;
> > +	u64 ctx_lo;
> > +
> > +	iommu = device_to_iommu(dev, &bus, &devfn);
> > +	if (!iommu)
> > +		return -ENODEV;
> > +	/* VT-d spec section 9.4 says pasid table size is encoded
> > as 2^(x+5) */
> > +	host_table_pasid_bits = intel_iommu_get_pts(iommu) +
> > MIN_NR_PASID_BITS;
> > +	if (!pasidt_binfo || pasidt_binfo->pasid_bits >
> > host_table_pasid_bits ||
> > +		pasidt_binfo->pasid_bits < MIN_NR_PASID_BITS) {
> > +		pr_err("Invalid gPASID bits %d, host range %d -
> > %d\n",
> > +			pasidt_binfo->pasid_bits,
> > +			MIN_NR_PASID_BITS, host_table_pasid_bits);
> > +		return -ERANGE;
> > +	}
> > +	if (!ecap_nest(iommu->ecap)) {
> > +		dev_err(dev, "Cannot bind PASID table, no nested
> > translation\n");
> > +		ret = -EINVAL;
> > +		goto out;
> > +	}  
> 
> Gratuitous use of pr_err, some of these look user reachable, for
> instance can vfio know in advance the supported widths or can the user
> trigger that pr_err at will?
Yes, the current IOMMU sysfs for vt-d does show the content of
capability registers so user could know in advance whether the nested
mode is supported. But I think we are in need of some generic interface
to enumerate IOMMU features. Here I am trying to prepare for the worst.
Are you concerned about security if user can trigger that error at
will? Sorry I didn't get the point.

>  Some of these errno values are also
> maybe not as descriptive as they could be.  For instance if the iommu
> doesn't support nesting, that's not a calling argument error, that's
> an unsupported device error, right?
> 
your are right, that is not invalid argument. You mean use ENODEV?

> > +	pdev = to_pci_dev(dev);
> > +	sid = PCI_DEVID(bus, devfn);
> > +	info = dev->archdata.iommu;
> > +
> > +	if (!info) {
> > +		dev_err(dev, "Invalid device domain info\n");
> > +		ret = -EINVAL;
> > +		goto out;
> > +	}
> > +	if (info->pasid_table_bound) {
> > +		dev_err(dev, "Device PASID table already bound\n");
> > +		ret = -EBUSY;
> > +		goto out;
> > +	}
> > +	if (!info->pasid_enabled) {
> > +		ret = pci_enable_pasid(pdev, info->pasid_supported
> > & ~1);
> > +		if (ret) {
> > +			dev_err(dev, "Failed to enable PASID\n");
> > +			goto out;
> > +		}
> > +	}
> > +	spin_lock_irqsave(&iommu->lock, flags);
> > +	context = iommu_context_addr(iommu, bus, devfn, 0);
> > +	if (!context_present(context)) {
> > +		dev_err(dev, "Context not present\n");
> > +		ret = -EINVAL;
> > +		goto out_unlock;
> > +	}
> > +
> > +	/* Anticipate guest to use SVM and owns the first level,
> > so we turn
> > +	 * nested mode on
> > +	 */
> > +	ctx_lo = context[0].lo;
> > +	ctx_lo |= CONTEXT_NESTE | CONTEXT_PRS | CONTEXT_PASIDE;
> > +	ctx_lo &= ~CONTEXT_TT_MASK;
> > +	ctx_lo |= CONTEXT_TT_DEV_IOTLB << 2;
> > +	context[0].lo = ctx_lo;
> > +
> > +	/* Assign guest PASID table pointer and size order */
> > +	ctx_lo = (pasidt_binfo->base_ptr & VTD_PAGE_MASK) |
> > +		(pasidt_binfo->pasid_bits - MIN_NR_PASID_BITS);  
> 
> Where does this IOMMU API interface define that base_ptr is 4K
> aligned or the format of the PASID table?  Are these all standardized
> or do they vary by host IOMMU?  If they're standards, maybe we could
> note that and the spec which defines them when we declare base_ptr.
> If they're IOMMU specific then I don't understand how we'll match a
> user provided PASID table to the requirements and format of the host
> IOMMU. Thanks,
> 
follow up in the other thread with Jean.

Thanks for the review.

Jacob
> Alex
> 
> > +	context[1].lo = ctx_lo;
> > +	/* make sure context entry is updated before flushing */
> > +	wmb();
> > +	did = dmar_domain->iommu_did[iommu->seq_id];
> > +	iommu->flush.flush_context(iommu, did,
> > +				(((u16)bus) << 8) | devfn,
> > +				DMA_CCMD_MASK_NOBIT,
> > +				DMA_CCMD_DEVICE_INVL);
> > +	iommu->flush.flush_iotlb(iommu, did, 0, 0,
> > DMA_TLB_DSI_FLUSH);
> > +	info->pasid_table_bound = 1;
> > +out_unlock:
> > +	spin_unlock_irqrestore(&iommu->lock, flags);
> > +out:
> > +	return ret;
> > +}
> > +
> > +static void intel_iommu_unbind_pasid_table(struct iommu_domain
> > *domain,
> > +					struct device *dev)
> > +{
> > +	struct intel_iommu *iommu;
> > +	struct dmar_domain *dmar_domain = to_dmar_domain(domain);
> > +	struct device_domain_info *info;
> > +	u8 bus, devfn;
> > +
> > +	info = dev->archdata.iommu;
> > +	if (!info) {
> > +		dev_err(dev, "Invalid device domain info\n");
> > +		return;
> > +	}
> > +	iommu = device_to_iommu(dev, &bus, &devfn);
> > +	if (!iommu) {
> > +		dev_err(dev, "No IOMMU for device to unbind PASID
> > table\n");
> > +		return;
> > +	}
> > +
> > +	domain_context_clear(iommu, dev);
> > +
> > +	domain_context_mapping_one(dmar_domain, iommu, bus, devfn);
> > +	info->pasid_table_bound = 0;
> > +}
> >  #endif /* CONFIG_INTEL_IOMMU_SVM */
> >  
> >  const struct iommu_ops intel_iommu_ops = {
> > @@ -5266,6 +5381,10 @@ const struct iommu_ops intel_iommu_ops = {
> >  	.domain_free		= intel_iommu_domain_free,
> >  	.attach_dev		= intel_iommu_attach_device,
> >  	.detach_dev		= intel_iommu_detach_device,
> > +#ifdef CONFIG_INTEL_IOMMU_SVM
> > +	.bind_pasid_table	= intel_iommu_bind_pasid_table,
> > +	.unbind_pasid_table	=
> > intel_iommu_unbind_pasid_table, +#endif
> >  	.map			= intel_iommu_map,
> >  	.unmap			= intel_iommu_unmap,
> >  	.map_sg			= default_iommu_map_sg,
> > diff --git a/include/linux/dma_remapping.h
> > b/include/linux/dma_remapping.h index 21b3e7d..db290b2 100644
> > --- a/include/linux/dma_remapping.h
> > +++ b/include/linux/dma_remapping.h
> > @@ -28,6 +28,7 @@
> >  
> >  #define CONTEXT_DINVE		(1ULL << 8)
> >  #define CONTEXT_PRS		(1ULL << 9)
> > +#define CONTEXT_NESTE		(1ULL << 10)
> >  #define CONTEXT_PASIDE		(1ULL << 11)
> >  
> >  struct intel_iommu;  
> 

[Jacob Pan]

  parent reply	other threads:[~2018-04-20 23:22 UTC|newest]

Thread overview: 69+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-16 21:48 [PATCH v4 00/22] IOMMU and VT-d driver support for Shared Virtual Address (SVA) Jacob Pan
2018-04-16 21:48 ` [PATCH v4 01/22] iommu: introduce bind_pasid_table API function Jacob Pan
2018-04-16 21:48 ` [PATCH v4 02/22] iommu/vt-d: move device_domain_info to header Jacob Pan
2018-04-16 21:48 ` [PATCH v4 03/22] iommu/vt-d: add a flag for pasid table bound status Jacob Pan
2018-04-16 21:48 ` [PATCH v4 04/22] iommu/vt-d: add bind_pasid_table function Jacob Pan
2018-04-17 19:10   ` Alex Williamson
2018-04-20 18:25     ` Jean-Philippe Brucker
2018-04-20 23:42       ` Jacob Pan
2018-05-29 20:09         ` Alex Williamson
2018-05-30  1:41           ` Tian, Kevin
2018-05-30  3:17             ` Alex Williamson
2018-05-30  3:45               ` Tian, Kevin
2018-05-30 11:53                 ` Jean-Philippe Brucker
2018-05-30 19:52                   ` Jacob Pan
2018-05-31  9:09                     ` Jean-Philippe Brucker
2018-06-05 17:32                       ` Jacob Pan
2018-06-06 11:20                         ` Jean-Philippe Brucker
2018-06-06 21:22                           ` Jacob Pan
2018-06-07 13:21                             ` Jean-Philippe Brucker
2018-04-20 23:22     ` Jacob Pan [this message]
2018-04-16 21:48 ` [PATCH v4 05/22] iommu: introduce iommu invalidate API function Jacob Pan
2018-04-20 18:19   ` Jean-Philippe Brucker
2018-04-23 20:43     ` Jacob Pan
2018-04-27 18:07       ` Jean-Philippe Brucker
2018-04-28  2:41         ` Tian, Kevin
2018-05-01 22:58         ` Jacob Pan
2018-05-02  9:31           ` Jean-Philippe Brucker
2018-05-04  4:46             ` Jacob Pan
2018-05-04 18:07               ` Jacob Pan
2018-05-08 10:35                 ` Jean-Philippe Brucker
2018-05-09 12:55                   ` Jacob Pan
2018-05-05 22:19   ` Jerry Snitselaar
2018-05-07 15:41     ` Jacob Pan
2018-04-16 21:48 ` [PATCH v4 06/22] iommu/vt-d: add definitions for PFSID Jacob Pan
2018-04-16 21:48 ` [PATCH v4 07/22] iommu/vt-d: fix dev iotlb pfsid use Jacob Pan
2018-04-16 21:48 ` [PATCH v4 08/22] iommu/vt-d: support flushing more translation cache types Jacob Pan
2018-04-16 21:48 ` [PATCH v4 09/22] iommu/vt-d: add svm/sva invalidate function Jacob Pan
2018-04-17 19:10   ` Alex Williamson
2018-04-20 22:36     ` Jacob Pan
2018-04-16 21:48 ` [PATCH v4 10/22] iommu: introduce device fault data Jacob Pan
2018-04-23 10:11   ` Jean-Philippe Brucker
2018-04-23 11:54     ` Jacob Pan
2018-05-20  8:17   ` Liu, Yi L
2018-05-21 23:16     ` Jacob Pan
2018-04-16 21:49 ` [PATCH v4 11/22] driver core: add per device iommu param Jacob Pan
2018-04-23 10:26   ` Greg Kroah-Hartman
2018-04-16 21:49 ` [PATCH v4 12/22] iommu: introduce device fault report API Jacob Pan
2018-04-23 11:30   ` Jean-Philippe Brucker
2018-04-24 18:29     ` Jacob Pan
2018-04-30 16:53   ` Jean-Philippe Brucker
2018-04-30 18:54     ` Jacob Pan
2018-04-16 21:49 ` [PATCH v4 13/22] iommu: introduce page response function Jacob Pan
2018-04-23 11:47   ` Jean-Philippe Brucker
2018-04-23 12:16     ` Jacob Pan
2018-04-23 15:50       ` Jean-Philippe Brucker
2018-04-16 21:49 ` [PATCH v4 14/22] iommu: handle page response timeout Jacob Pan
2018-04-23 15:36   ` Jean-Philippe Brucker
2018-04-25 15:37     ` Jacob Pan
2018-04-30 10:58       ` Jean-Philippe Brucker
2018-04-30 17:54         ` Jacob Pan
2018-04-16 21:49 ` [PATCH v4 15/22] iommu/config: add build dependency for dmar Jacob Pan
2018-04-16 21:49 ` [PATCH v4 16/22] iommu/vt-d: report non-recoverable faults to device Jacob Pan
2018-04-16 21:49 ` [PATCH v4 17/22] iommu/intel-svm: report device page request Jacob Pan
2018-04-16 21:49 ` [PATCH v4 18/22] iommu/intel-svm: replace dev ops with fault report API Jacob Pan
2018-04-16 21:49 ` [PATCH v4 19/22] iommu/intel-svm: do not flush iotlb for viommu Jacob Pan
2018-04-16 21:49 ` [PATCH v4 20/22] iommu/vt-d: add intel iommu page response function Jacob Pan
2018-04-16 21:49 ` [PATCH v4 21/22] trace/iommu: add sva trace events Jacob Pan
2018-04-16 21:49 ` [PATCH v4 22/22] iommu: use sva invalidate and device fault trace event Jacob Pan
  -- strict thread matches above, loose matches on Subject: below --
2018-03-23  3:11 [PATCH v4 00/22] IOMMU and VT-d driver support for Shared Virtual Address (SVA) Jacob Pan
2018-03-23  3:11 ` [PATCH v4 04/22] iommu/vt-d: add bind_pasid_table function 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=20180420162259.2d29659a@jacob-builder \
    --to=jacob.jun.pan@linux.intel.com \
    --cc=alex.williamson@redhat.com \
    --cc=ashok.raj@intel.com \
    --cc=baolu.lu@linux.intel.com \
    --cc=dwmw2@infradead.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=hch@infradead.org \
    --cc=iommu@lists.linux-foundation.org \
    --cc=jean-philippe.brucker@arm.com \
    --cc=joro@8bytes.org \
    --cc=kevin.tian@intel.com \
    --cc=khali@linux-fr.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=rafael.j.wysocki@intel.com \
    --cc=yi.l.liu@intel.com \
    --cc=yi.l.liu@linux.intel.com \
    --subject='Re: [PATCH v4 04/22] iommu/vt-d: add bind_pasid_table function' \
    /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

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).