[RFC PATCH 05/16] mm/madvise: define and use madvise_behavior struct for madvise_do_behavior()

[SeongJae Park]

To implement batched tlb flushes for MADV_DONTNEED[_LOCKED] and
MADV_FREE, an mmu_gather object in addition to the behavior integer need
to be passed to the internal logics.  Define a struct for passing such
information together with the behavior value without increasing number
of parameters of all code paths towards the internal logic.

Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
---
 mm/madvise.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/mm/madvise.c b/mm/madvise.c
index c5e1a4d1df72..3346e593e07d 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -1665,9 +1665,15 @@ static bool is_memory_populate(int behavior)
 	}
 }
 
+struct madvise_behavior {
+	int behavior;
+};
+
 static int madvise_do_behavior(struct mm_struct *mm,
-		unsigned long start, size_t len_in, int behavior)
+		unsigned long start, size_t len_in,
+		struct madvise_behavior *madv_behavior)
 {
+	int behavior = madv_behavior->behavior;
 	struct blk_plug plug;
 	unsigned long end;
 	int error;
@@ -1762,13 +1768,14 @@ static int madvise_do_behavior(struct mm_struct *mm,
 int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int behavior)
 {
 	int error;
+	struct madvise_behavior madv_behavior = {.behavior = behavior};
 
 	if (madvise_should_skip(start, len_in, behavior, &error))
 		return error;
 	error = madvise_lock(mm, behavior);
 	if (error)
 		return error;
-	error = madvise_do_behavior(mm, start, len_in, behavior);
+	error = madvise_do_behavior(mm, start, len_in, &madv_behavior);
 	madvise_unlock(mm, behavior);
 
 	return error;
@@ -1785,6 +1792,7 @@ static ssize_t vector_madvise(struct mm_struct *mm, struct iov_iter *iter,
 {
 	ssize_t ret = 0;
 	size_t total_len;
+	struct madvise_behavior madv_behavior = {.behavior = behavior};
 
 	total_len = iov_iter_count(iter);
 
@@ -1800,7 +1808,8 @@ static ssize_t vector_madvise(struct mm_struct *mm, struct iov_iter *iter,
 		if (madvise_should_skip(start, len_in, behavior, &error))
 			ret = error;
 		else
-			ret = madvise_do_behavior(mm, start, len_in, behavior);
+			ret = madvise_do_behavior(mm, start, len_in,
+					&madv_behavior);
 		/*
 		 * An madvise operation is attempting to restart the syscall,
 		 * but we cannot proceed as it would not be correct to repeat
-- 
2.39.5