If static identity domain is created, IOMMU driver needs to update
si_domain page table when memory hotplug event happens. Otherwise
PCI device DMA operations can't access the hot-added memory regions.
Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
---
drivers/iommu/intel-iommu.c | 52 ++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 51 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 83e3ed4..35a987d 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -33,6 +33,7 @@
#include <linux/dmar.h>
#include <linux/dma-mapping.h>
#include <linux/mempool.h>
+#include <linux/memory.h>
#include <linux/timer.h>
#include <linux/iova.h>
#include <linux/iommu.h>
@@ -3689,6 +3690,54 @@ static struct notifier_block device_nb = {
.notifier_call = device_notifier,
};
+static int intel_iommu_memory_notifier(struct notifier_block *nb,
+ unsigned long val, void *v)
+{
+ struct memory_notify *mhp = v;
+ unsigned long long start, end;
+ struct iova *iova;
+
+ switch (val) {
+ case MEM_GOING_ONLINE:
+ start = mhp->start_pfn << PAGE_SHIFT;
+ end = ((mhp->start_pfn + mhp->nr_pages) << PAGE_SHIFT) - 1;
+ if (iommu_domain_identity_map(si_domain, start, end)) {
+ pr_warn("dmar: failed to build identity map for [%llx-%llx]\n",
+ start, end);
+ return NOTIFY_BAD;
+ }
+ break;
+ case MEM_OFFLINE:
+ case MEM_CANCEL_ONLINE:
+ /* TODO: enhance RB-tree and IOVA code to support of splitting iova */
+ iova = find_iova(&si_domain->iovad, mhp->start_pfn);
+ if (iova) {
+ unsigned long start_pfn, last_pfn;
+ struct dmar_drhd_unit *drhd;
+ struct intel_iommu *iommu;
+
+ start_pfn = mm_to_dma_pfn(iova->pfn_lo);
+ last_pfn = mm_to_dma_pfn(iova->pfn_hi + 1) - 1;
+ dma_pte_clear_range(si_domain, start_pfn, last_pfn);
+ dma_pte_free_pagetable(si_domain, start_pfn, last_pfn);
+ rcu_read_lock();
+ for_each_active_iommu(iommu, drhd)
+ iommu_flush_iotlb_psi(iommu, si_domain->id,
+ start_pfn, last_pfn - start_pfn + 1, 0);
+ rcu_read_unlock();
+ __free_iova(&si_domain->iovad, iova);
+ }
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block intel_iommu_memory_nb = {
+ .notifier_call = intel_iommu_memory_notifier,
+ .priority = 0
+};
+
int __init intel_iommu_init(void)
{
int ret = -ENODEV;
@@ -3761,8 +3810,9 @@ int __init intel_iommu_init(void)
init_iommu_pm_ops();
bus_set_iommu(&pci_bus_type, &intel_iommu_ops);
-
bus_register_notifier(&pci_bus_type, &device_nb);
+ if (si_domain)
+ register_memory_notifier(&intel_iommu_memory_nb);
intel_iommu_enabled = 1;
--
1.7.10.4
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
