iommu/vt-d: avoid dev iotlb logic for domains with no dev iotlbs

This patch avoids taking the device_domain_lock in iommu_flush_dev_iotlb()
for domains with no dev iotlb devices.

Signed-off-by: Omer Peleg <omer@cs.technion.ac.il>
[gvdl@google.com: fixed locking issues]
Signed-off-by: Godfrey van der Linden <gvdl@google.com>
[mad@cs.technion.ac.il: rebased and reworded the commit message]
Signed-off-by: Adam Morrison <mad@cs.technion.ac.il>
Reviewed-by: Shaohua Li <shli@fb.com>
Reviewed-by: Ben Serebrin <serebrin@google.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This commit is contained in:
Omer Peleg 2016-04-20 19:03:35 +03:00 committed by David Woodhouse
parent 769530e4ba
commit 0824c5920b

View file

@ -391,6 +391,7 @@ struct dmar_domain {
* domain ids are 16 bit wide according
* to VT-d spec, section 9.3 */
bool has_iotlb_device;
struct list_head devices; /* all devices' list */
struct iova_domain iovad; /* iova's that belong to this domain */
@ -1464,10 +1465,35 @@ iommu_support_dev_iotlb (struct dmar_domain *domain, struct intel_iommu *iommu,
return NULL;
}
static void domain_update_iotlb(struct dmar_domain *domain)
{
struct device_domain_info *info;
bool has_iotlb_device = false;
assert_spin_locked(&device_domain_lock);
list_for_each_entry(info, &domain->devices, link) {
struct pci_dev *pdev;
if (!info->dev || !dev_is_pci(info->dev))
continue;
pdev = to_pci_dev(info->dev);
if (pdev->ats_enabled) {
has_iotlb_device = true;
break;
}
}
domain->has_iotlb_device = has_iotlb_device;
}
static void iommu_enable_dev_iotlb(struct device_domain_info *info)
{
struct pci_dev *pdev;
assert_spin_locked(&device_domain_lock);
if (!info || !dev_is_pci(info->dev))
return;
@ -1487,6 +1513,7 @@ static void iommu_enable_dev_iotlb(struct device_domain_info *info)
#endif
if (info->ats_supported && !pci_enable_ats(pdev, VTD_PAGE_SHIFT)) {
info->ats_enabled = 1;
domain_update_iotlb(info->domain);
info->ats_qdep = pci_ats_queue_depth(pdev);
}
}
@ -1495,6 +1522,8 @@ static void iommu_disable_dev_iotlb(struct device_domain_info *info)
{
struct pci_dev *pdev;
assert_spin_locked(&device_domain_lock);
if (!dev_is_pci(info->dev))
return;
@ -1503,6 +1532,7 @@ static void iommu_disable_dev_iotlb(struct device_domain_info *info)
if (info->ats_enabled) {
pci_disable_ats(pdev);
info->ats_enabled = 0;
domain_update_iotlb(info->domain);
}
#ifdef CONFIG_INTEL_IOMMU_SVM
if (info->pri_enabled) {
@ -1523,6 +1553,9 @@ static void iommu_flush_dev_iotlb(struct dmar_domain *domain,
unsigned long flags;
struct device_domain_info *info;
if (!domain->has_iotlb_device)
return;
spin_lock_irqsave(&device_domain_lock, flags);
list_for_each_entry(info, &domain->devices, link) {
if (!info->ats_enabled)
@ -1740,6 +1773,7 @@ static struct dmar_domain *alloc_domain(int flags)
memset(domain, 0, sizeof(*domain));
domain->nid = -1;
domain->flags = flags;
domain->has_iotlb_device = false;
INIT_LIST_HEAD(&domain->devices);
return domain;