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 | 71 ++++++++++++++++++++++++++++++++++++++++++-
drivers/iommu/iova.c | 64 ++++++++++++++++++++++++++++++++++----
include/linux/iova.h | 2 ++
3 files changed, 130 insertions(+), 7 deletions(-)
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index dd576c0..484d669 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>
@@ -3683,6 +3684,73 @@ 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;
+ unsigned long start_vpfn, last_vpfn;
+
+ 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:
+ start_vpfn = mm_to_dma_pfn(mhp->start_pfn);
+ last_vpfn = mm_to_dma_pfn(mhp->start_pfn + mhp->nr_pages - 1);
+ while (start_vpfn <= last_vpfn) {
+ struct iova *iova;
+ struct dmar_drhd_unit *drhd;
+ struct intel_iommu *iommu;
+
+ iova = find_iova(&si_domain->iovad, start_vpfn);
+ if (iova == NULL) {
+ pr_debug("dmar: failed get IOVA for PFN %lx\n",
+ start_vpfn);
+ break;
+ }
+
+ iova = split_and_remove_iova(&si_domain->iovad, iova,
+ start_vpfn, last_vpfn);
+ if (iova == NULL) {
+ pr_warn("dmar: failed to split IOVA PFN [%lx-%lx]\n",
+ start_vpfn, last_vpfn);
+ return NOTIFY_BAD;
+ }
+
+ rcu_read_lock();
+ for_each_active_iommu(iommu, drhd)
+ iommu_flush_iotlb_psi(iommu, si_domain->id,
+ iova->pfn_lo,
+ iova->pfn_hi - iova->pfn_lo + 1, 0);
+ rcu_read_unlock();
+ dma_pte_clear_range(si_domain, iova->pfn_lo,
+ iova->pfn_hi);
+ dma_pte_free_pagetable(si_domain, iova->pfn_lo,
+ iova->pfn_hi);
+
+ start_vpfn = iova->pfn_hi + 1;
+ free_iova_mem(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;
@@ -3755,8 +3823,9 @@ 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 && !hw_pass_through)
+ register_memory_notifier(&intel_iommu_memory_nb);
intel_iommu_enabled = 1;
diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
index 67da6cff..f6b17e6 100644
--- a/drivers/iommu/iova.c
+++ b/drivers/iommu/iova.c
@@ -342,19 +342,30 @@ __is_range_overlap(struct rb_node *node,
return 0;
}
+static inline struct iova *
+alloc_and_init_iova(unsigned long pfn_lo, unsigned long pfn_hi)
+{
+ struct iova *iova;
+
+ iova = alloc_iova_mem();
+ if (iova) {
+ iova->pfn_lo = pfn_lo;
+ iova->pfn_hi = pfn_hi;
+ }
+
+ return iova;
+}
+
static struct iova *
__insert_new_range(struct iova_domain *iovad,
unsigned long pfn_lo, unsigned long pfn_hi)
{
struct iova *iova;
- iova = alloc_iova_mem();
- if (!iova)
- return iova;
+ iova = alloc_and_init_iova(pfn_lo, pfn_hi);
+ if (iova)
+ iova_insert_rbtree(&iovad->rbroot, iova);
- iova->pfn_hi = pfn_hi;
- iova->pfn_lo = pfn_lo;
- iova_insert_rbtree(&iovad->rbroot, iova);
return iova;
}
@@ -433,3 +444,44 @@ copy_reserved_iova(struct iova_domain *from, struct iova_domain *to)
}
spin_unlock_irqrestore(&from->iova_rbtree_lock, flags);
}
+
+struct iova *
+split_and_remove_iova(struct iova_domain *iovad, struct iova *iova,
+ unsigned long pfn_lo, unsigned long pfn_hi)
+{
+ unsigned long flags;
+ struct iova *prev = NULL, *next = NULL;
+
+ spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
+ if (iova->pfn_lo < pfn_lo) {
+ prev = alloc_and_init_iova(iova->pfn_lo, pfn_lo - 1);
+ if (prev == NULL)
+ goto error;
+ }
+ if (iova->pfn_hi > pfn_hi) {
+ next = alloc_and_init_iova(pfn_hi + 1, iova->pfn_hi);
+ if (next == NULL)
+ goto error;
+ }
+
+ __cached_rbnode_delete_update(iovad, iova);
+ rb_erase(&iova->node, &iovad->rbroot);
+
+ if (prev) {
+ iova_insert_rbtree(&iovad->rbroot, prev);
+ iova->pfn_lo = pfn_lo;
+ }
+ if (next) {
+ iova_insert_rbtree(&iovad->rbroot, next);
+ iova->pfn_hi = pfn_hi;
+ }
+ spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+
+ return iova;
+
+error:
+ spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+ if (prev)
+ free_iova_mem(prev);
+ return NULL;
+}
diff --git a/include/linux/iova.h b/include/linux/iova.h
index 76a0759..3277f47 100644
--- a/include/linux/iova.h
+++ b/include/linux/iova.h
@@ -47,5 +47,7 @@ void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
void init_iova_domain(struct iova_domain *iovad, unsigned long pfn_32bit);
struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
void put_iova_domain(struct iova_domain *iovad);
+struct iova *split_and_remove_iova(struct iova_domain *iovad,
+ struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi);
#endif
--
1.7.10.4
--
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