This patch reports nesting info when iommu_domain_get_attr() is called with
DOMAIN_ATTR_NESTING and one domain with nesting set.
Cc: Kevin Tian <kevin.tian@xxxxxxxxx>
CC: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
Cc: Alex Williamson <alex.williamson@xxxxxxxxxx>
Cc: Eric Auger <eric.auger@xxxxxxxxxx>
Cc: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Signed-off-by: Liu Yi L <yi.l.liu@xxxxxxxxx>
Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
---
v6 -> v7:
*) split the patch in v6 into two patches:
[PATCH v7 15/16] iommu/vt-d: Only support nesting when nesting caps are consistent across iommu units
[PATCH v7 16/16] iommu/vt-d: Support reporting nesting capability info
v2 -> v3:
*) remove cap/ecap_mask in iommu_nesting_info.
---
drivers/iommu/intel/iommu.c | 74 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 74 insertions(+)
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 38c6c9b..e46214e 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -6089,6 +6089,79 @@ intel_iommu_domain_set_attr(struct iommu_domain *domain,
return ret;
}
+static int intel_iommu_get_nesting_info(struct iommu_domain *domain,
+ struct iommu_nesting_info *info)
+{
+ struct dmar_domain *dmar_domain = to_dmar_domain(domain);
+ u64 cap = VTD_CAP_MASK, ecap = VTD_ECAP_MASK;
+ struct device_domain_info *domain_info;
+ struct iommu_nesting_info_vtd vtd;
+ unsigned int size;
+
+ if (!info)
+ return -EINVAL;
+
+ if (domain->type != IOMMU_DOMAIN_UNMANAGED ||
+ !(dmar_domain->flags & DOMAIN_FLAG_NESTING_MODE))
+ return -ENODEV;
+
+ size = sizeof(struct iommu_nesting_info);
+ /*
+ * if provided buffer size is smaller than expected, should
+ * return 0 and also the expected buffer size to caller.
+ */
+ if (info->argsz < size) {
+ info->argsz = size;
+ return 0;
+ }
+
+ /*
+ * arbitrary select the first domain_info as all nesting
+ * related capabilities should be consistent across iommu
+ * units.
+ */
+ domain_info = list_first_entry(&dmar_domain->devices,
+ struct device_domain_info, link);
+ cap &= domain_info->iommu->cap;
+ ecap &= domain_info->iommu->ecap;
+
+ info->addr_width = dmar_domain->gaw;
+ info->format = IOMMU_PASID_FORMAT_INTEL_VTD;
+ info->features = IOMMU_NESTING_FEAT_SYSWIDE_PASID |
+ IOMMU_NESTING_FEAT_BIND_PGTBL |
+ IOMMU_NESTING_FEAT_CACHE_INVLD;
+ info->pasid_bits = ilog2(intel_pasid_max_id);
+ memset(&info->padding, 0x0, 12);
+
+ vtd.flags = 0;
+ vtd.cap_reg = cap;
+ vtd.ecap_reg = ecap;
+
+ memcpy(&info->vendor.vtd, &vtd, sizeof(vtd));
+ return 0;
+}
+
+static int intel_iommu_domain_get_attr(struct iommu_domain *domain,
+ enum iommu_attr attr, void *data)
+{
+ switch (attr) {
+ case DOMAIN_ATTR_NESTING:
+ {
+ struct iommu_nesting_info *info =
+ (struct iommu_nesting_info *)data;
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&device_domain_lock, flags);
+ ret = intel_iommu_get_nesting_info(domain, info);
+ spin_unlock_irqrestore(&device_domain_lock, flags);
+ return ret;
+ }
+ default:
+ return -ENOENT;
+ }
+}
+
/*
* Check that the device does not live on an external facing PCI port that is
* marked as untrusted. Such devices should not be able to apply quirks and
@@ -6111,6 +6184,7 @@ const struct iommu_ops intel_iommu_ops = {
.domain_alloc = intel_iommu_domain_alloc,
.domain_free = intel_iommu_domain_free,
.domain_set_attr = intel_iommu_domain_set_attr,
+ .domain_get_attr = intel_iommu_domain_get_attr,
.attach_dev = intel_iommu_attach_device,
.detach_dev = intel_iommu_detach_device,
.aux_attach_dev = intel_iommu_aux_attach_device,
--
2.7.4
