1 files changed, 22 insertions, 11 deletions

diff --git a/mm/hmm.c b/mm/hmm.c
index a3d532ff7c3d..b4e9afdc2181 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -126,10 +126,8 @@ void hmm_mm_destroy(struct mm_struct *mm)
 	kfree(mm->hmm);
 }
 
-static void hmm_invalidate_range(struct hmm *hmm,
-				 enum hmm_update_type action,
-				 unsigned long start,
-				 unsigned long end)
+static int hmm_invalidate_range(struct hmm *hmm,
+				const struct hmm_update *update)
 {
 	struct hmm_mirror *mirror;
 	struct hmm_range *range;
@@ -138,22 +136,30 @@ static void hmm_invalidate_range(struct hmm *hmm,
 	list_for_each_entry(range, &hmm->ranges, list) {
 		unsigned long addr, idx, npages;
 
-		if (end < range->start || start >= range->end)
+		if (update->end < range->start || update->start >= range->end)
 			continue;
 
 		range->valid = false;
-		addr = max(start, range->start);
+		addr = max(update->start, range->start);
 		idx = (addr - range->start) >> PAGE_SHIFT;
-		npages = (min(range->end, end) - addr) >> PAGE_SHIFT;
+		npages = (min(range->end, update->end) - addr) >> PAGE_SHIFT;
 		memset(&range->pfns[idx], 0, sizeof(*range->pfns) * npages);
 	}
 	spin_unlock(&hmm->lock);
 
 	down_read(&hmm->mirrors_sem);
-	list_for_each_entry(mirror, &hmm->mirrors, list)
-		mirror->ops->sync_cpu_device_pagetables(mirror, action,
-							start, end);
+	list_for_each_entry(mirror, &hmm->mirrors, list) {
+		int ret;
+
+		ret = mirror->ops->sync_cpu_device_pagetables(mirror, update);
+		if (!update->blockable && ret == -EAGAIN) {
+			up_read(&hmm->mirrors_sem);
+			return -EAGAIN;
+		}
+	}
 	up_read(&hmm->mirrors_sem);
+
+	return 0;
 }
 
 static void hmm_release(struct mmu_notifier *mn, struct mm_struct *mm)
@@ -202,11 +208,16 @@ static void hmm_invalidate_range_end(struct mmu_notifier *mn,
 				     unsigned long start,
 				     unsigned long end)
 {
+	struct hmm_update update;
 	struct hmm *hmm = mm->hmm;
 
 	VM_BUG_ON(!hmm);
 
-	hmm_invalidate_range(mm->hmm, HMM_UPDATE_INVALIDATE, start, end);
+	update.start = start;
+	update.end = end;
+	update.event = HMM_UPDATE_INVALIDATE;
+	update.blockable = true;
+	hmm_invalidate_range(hmm, &update);
 }
 
 static const struct mmu_notifier_ops hmm_mmu_notifier_ops = {