Hi,
On 09/06/2018 03:35 AM, Alex Williamson wrote:
On Thu, 30 Aug 2018 12:09:14 +0800
Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> wrote:
Add the response to IOMMU_CAP_AUX_DOMAIN capability query
through iommu_capable(). Return true if IOMMUs support the
scalable mode, return false otherwise.
Cc: Ashok Raj <ashok.raj@xxxxxxxxx>
Cc: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
Cc: Kevin Tian <kevin.tian@xxxxxxxxx>
Cc: Liu Yi L <yi.l.liu@xxxxxxxxx>
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
drivers/iommu/intel-iommu.c | 31 +++++++++++++++++++++++++++++--
1 file changed, 29 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 3e49d4029058..891ae70e7bf2 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -5193,12 +5193,39 @@ static phys_addr_t intel_iommu_iova_to_phys(struct iommu_domain *domain,
return phys;
}
+static inline bool scalable_mode_support(void)
+{
+ struct dmar_drhd_unit *drhd;
+ struct intel_iommu *iommu;
+ bool ret = true;
+
+ rcu_read_lock();
+ for_each_active_iommu(iommu, drhd) {
+ if (!sm_supported(iommu)) {
+ ret = false;
+ break;
+ }
+ }
+ rcu_read_unlock();
+
+ return ret;
+}
+
static bool intel_iommu_capable(enum iommu_cap cap)
{
- if (cap == IOMMU_CAP_CACHE_COHERENCY)
+ switch (cap) {
+ case IOMMU_CAP_CACHE_COHERENCY:
return domain_update_iommu_snooping(NULL) == 1;
- if (cap == IOMMU_CAP_INTR_REMAP)
+ case IOMMU_CAP_INTR_REMAP:
return irq_remapping_enabled == 1;
+ case IOMMU_CAP_AUX_DOMAIN:
+ return scalable_mode_support();
+ case IOMMU_CAP_NOEXEC:
+ /* PASSTHROUGH */
+ default:
+ pr_info("Unsupported capability query %d\n", cap);
+ break;
Please don't do this, there's no reason to be noisy about a query of a
capability that VT-d doesn't know about. We implement capabilities
exactly so that relevant drivers can expose a feature and others can
happily (and quietly) ignore them. Thanks,
Fair enough. I will remove it in the next version.
Best regards,
Lu Baolu
