From: Eric Auger <eric.auger@redhat.com>
To: eric.auger.pro@gmail.com, eric.auger@redhat.com,
iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu,
joro@8bytes.org, alex.williamson@redhat.com,
jacob.jun.pan@linux.intel.com, yi.l.liu@intel.com,
jean-philippe.brucker@arm.com, will.deacon@arm.com,
robin.murphy@arm.com
Cc: marc.zyngier@arm.com, peter.maydell@linaro.org
Subject: [PATCH v10 10/13] iommu/smmuv3: Nested mode single MSI doorbell per domain enforcement
Date: Fri, 20 Mar 2020 17:09:29 +0100 [thread overview]
Message-ID: <20200320160932.27222-11-eric.auger@redhat.com> (raw)
In-Reply-To: <20200320160932.27222-1-eric.auger@redhat.com>
In nested mode we enforce the rule that all devices belonging
to the same iommu_domain share the same msi_domain.
Indeed if there were several physical MSI doorbells being used
within a single iommu_domain, it becomes really difficult to
resolve the nested stage mapping translating into the correct
physical doorbell. So let's forbid this situation.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
drivers/iommu/arm-smmu-v3.c | 41 +++++++++++++++++++++++++++++++++++++
1 file changed, 41 insertions(+)
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 538e368c2e13..84dce0b2e935 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -2890,6 +2890,37 @@ static void arm_smmu_detach_dev(struct arm_smmu_master *master)
arm_smmu_install_ste_for_dev(master);
}
+static bool arm_smmu_share_msi_domain(struct iommu_domain *domain,
+ struct device *dev)
+{
+ struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+ struct irq_domain *irqd = dev_get_msi_domain(dev);
+ struct arm_smmu_master *master;
+ unsigned long flags;
+ bool share = false;
+
+ if (!irqd)
+ return true;
+
+ spin_lock_irqsave(&smmu_domain->devices_lock, flags);
+ list_for_each_entry(master, &smmu_domain->devices, domain_head) {
+ struct irq_domain *d = dev_get_msi_domain(master->dev);
+
+ if (!d)
+ continue;
+ if (irqd != d) {
+ dev_info(dev, "Nested mode forbids to attach devices "
+ "using different physical MSI doorbells "
+ "to the same iommu_domain");
+ goto unlock;
+ }
+ }
+ share = true;
+unlock:
+ spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
+ return share;
+}
+
static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
{
int ret = 0;
@@ -2931,6 +2962,16 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
ret = -EINVAL;
goto out_unlock;
}
+ /*
+ * In nested mode we must check all devices belonging to the
+ * domain share the same physical MSI doorbell. Otherwise nested
+ * stage MSI binding is not supported.
+ */
+ if (smmu_domain->stage == ARM_SMMU_DOMAIN_NESTED &&
+ !arm_smmu_share_msi_domain(domain, dev)) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
master->domain = smmu_domain;
--
2.20.1
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
next prev parent reply other threads:[~2020-03-20 16:11 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-20 16:09 [PATCH v10 00/13] SMMUv3 Nested Stage Setup (IOMMU part) Eric Auger
2020-03-20 16:09 ` [PATCH v10 01/13] iommu: Introduce attach/detach_pasid_table API Eric Auger
2020-03-20 16:09 ` [PATCH v10 02/13] iommu: Introduce bind/unbind_guest_msi Eric Auger
2020-03-20 16:09 ` [PATCH v10 03/13] iommu/arm-smmu-v3: Maintain a SID->device structure Eric Auger
2020-03-20 16:09 ` [PATCH v10 04/13] iommu/smmuv3: Dynamically allocate s1_cfg and s2_cfg Eric Auger
2020-03-20 16:09 ` [PATCH v10 05/13] iommu/smmuv3: Get prepared for nested stage support Eric Auger
2020-03-20 16:09 ` [PATCH v10 06/13] iommu/smmuv3: Implement attach/detach_pasid_table Eric Auger
2020-03-20 16:09 ` [PATCH v10 07/13] iommu/smmuv3: Allow stage 1 invalidation with unmanaged ASIDs Eric Auger
2020-03-20 16:09 ` [PATCH v10 08/13] iommu/smmuv3: Implement cache_invalidate Eric Auger
2020-03-20 16:09 ` [PATCH v10 09/13] dma-iommu: Implement NESTED_MSI cookie Eric Auger
2020-03-20 22:20 ` kbuild test robot
2020-03-20 16:09 ` Eric Auger [this message]
2020-03-20 16:09 ` [PATCH v10 11/13] iommu/smmuv3: Enforce incompatibility between nested mode and HW MSI regions Eric Auger
2020-03-20 16:09 ` [PATCH v10 12/13] iommu/smmuv3: Implement bind/unbind_guest_msi Eric Auger
2020-03-20 16:09 ` [PATCH v10 13/13] iommu/smmuv3: Report non recoverable faults Eric Auger
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=20200320160932.27222-11-eric.auger@redhat.com \
--to=eric.auger@redhat.com \
--cc=alex.williamson@redhat.com \
--cc=eric.auger.pro@gmail.com \
--cc=iommu@lists.linux-foundation.org \
--cc=jacob.jun.pan@linux.intel.com \
--cc=jean-philippe.brucker@arm.com \
--cc=joro@8bytes.org \
--cc=kvm@vger.kernel.org \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=linux-kernel@vger.kernel.org \
--cc=marc.zyngier@arm.com \
--cc=peter.maydell@linaro.org \
--cc=robin.murphy@arm.com \
--cc=will.deacon@arm.com \
--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).