iommu/vt-d: Report domain usage in sysfs
authorAlex Williamson <alex.williamson@redhat.com>
Tue, 14 Jul 2015 21:24:53 +0000 (15:24 -0600)
committerJoerg Roedel <jroedel@suse.de>
Mon, 3 Aug 2015 14:30:57 +0000 (16:30 +0200)
Debugging domain ID leakage typically requires long running tests in
order to exhaust the domain ID space or kernel instrumentation to
track the setting and clearing of bits.  A couple trivial intel-iommu
specific sysfs extensions make it much easier to expose the IOMMU
capabilities and current usage.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
drivers/iommu/intel-iommu.c

index 0be23c589d3b31263f3685b80cfeb933ac414a85..013cbc2005797058e0388f8d59eeadbd6e176de5 100644 (file)
@@ -4449,11 +4449,32 @@ static ssize_t intel_iommu_show_ecap(struct device *dev,
 }
 static DEVICE_ATTR(ecap, S_IRUGO, intel_iommu_show_ecap, NULL);
 
+static ssize_t intel_iommu_show_ndoms(struct device *dev,
+                                     struct device_attribute *attr,
+                                     char *buf)
+{
+       struct intel_iommu *iommu = dev_get_drvdata(dev);
+       return sprintf(buf, "%ld\n", cap_ndoms(iommu->cap));
+}
+static DEVICE_ATTR(domains_supported, S_IRUGO, intel_iommu_show_ndoms, NULL);
+
+static ssize_t intel_iommu_show_ndoms_used(struct device *dev,
+                                          struct device_attribute *attr,
+                                          char *buf)
+{
+       struct intel_iommu *iommu = dev_get_drvdata(dev);
+       return sprintf(buf, "%d\n", bitmap_weight(iommu->domain_ids,
+                                                 cap_ndoms(iommu->cap)));
+}
+static DEVICE_ATTR(domains_used, S_IRUGO, intel_iommu_show_ndoms_used, NULL);
+
 static struct attribute *intel_iommu_attrs[] = {
        &dev_attr_version.attr,
        &dev_attr_address.attr,
        &dev_attr_cap.attr,
        &dev_attr_ecap.attr,
+       &dev_attr_domains_supported.attr,
+       &dev_attr_domains_used.attr,
        NULL,
 };