[PATCH] mm/mmu_notifier: Remove unused mmu_notifier_range_update_to_read_only export

[Alistair Popple <apopple@nvidia.com>]

mmu_notifier_range_update_to_read_only() was originally introduced in
commit c6d23413f81b ("mm/mmu_notifier:
mmu_notifier_range_update_to_read_only() helper") as an optimisation
for device drivers that know a range has only been mapped
read-only. However there are no users of this feature so remove it. As
it is the only user of the struct mmu_notifier_range.vma field remove
that also.

Signed-off-by: Alistair Popple <apopple@nvidia.com>
---
 include/linux/mmu_notifier.h |  2 --
 mm/mmu_notifier.c            | 10 ----------
 2 files changed, 12 deletions(-)

diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h
index d6c06e140277..252e44afcc70 100644
--- a/include/linux/mmu_notifier.h
+++ b/include/linux/mmu_notifier.h
@@ -269,7 +269,6 @@ extern struct lockdep_map __mmu_notifier_invalidate_range_start_map;
 #endif
 
 struct mmu_notifier_range {
-	struct vm_area_struct *vma;
 	struct mm_struct *mm;
 	unsigned long start;
 	unsigned long end;
@@ -519,7 +518,6 @@ static inline void mmu_notifier_range_init(struct mmu_notifier_range *range,
 					   unsigned long start,
 					   unsigned long end)
 {
-	range->vma = vma;
 	range->event = event;
 	range->mm = mm;
 	range->start = start;
diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c
index f45ff1b7626a..50c0dde1354f 100644
--- a/mm/mmu_notifier.c
+++ b/mm/mmu_notifier.c
@@ -1120,13 +1120,3 @@ void mmu_notifier_synchronize(void)
 	synchronize_srcu(&srcu);
 }
 EXPORT_SYMBOL_GPL(mmu_notifier_synchronize);
-
-bool
-mmu_notifier_range_update_to_read_only(const struct mmu_notifier_range *range)
-{
-	if (!range->vma || range->event != MMU_NOTIFY_PROTECTION_VMA)
-		return false;
-	/* Return true if the vma still have the read flag set. */
-	return range->vma->vm_flags & VM_READ;
-}
-EXPORT_SYMBOL_GPL(mmu_notifier_range_update_to_read_only);
-- 
2.35.1