[PATCH v2] f2fs: provide f2fs_balance_fs to __write_node_page

[Yunlong Song <yunlong.song@xxxxxxxxxx>]

Let node writeback also do f2fs_balance_fs to ensure there are always enough free
segments.

Signed-off-by: Yunlong Song <yunlong.song@xxxxxxxxxx>
---
 fs/f2fs/checkpoint.c |  2 +-
 fs/f2fs/f2fs.h       |  2 +-
 fs/f2fs/node.c       | 14 ++++++++------
 3 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 5b876f6..3c84a25 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -1017,7 +1017,7 @@ static int block_operations(struct f2fs_sb_info *sbi)
 
 	if (get_pages(sbi, F2FS_DIRTY_NODES)) {
 		up_write(&sbi->node_write);
-		err = sync_node_pages(sbi, &wbc);
+		err = sync_node_pages(sbi, &wbc, false);
 		if (err) {
 			up_write(&sbi->node_change);
 			f2fs_unlock_all(sbi);
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 94a88b2..f69051b 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2293,7 +2293,7 @@ struct page *new_node_page(struct dnode_of_data *dn,
 void move_node_page(struct page *node_page, int gc_type);
 int fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
 			struct writeback_control *wbc, bool atomic);
-int sync_node_pages(struct f2fs_sb_info *sbi, struct writeback_control *wbc);
+int sync_node_pages(struct f2fs_sb_info *sbi, struct writeback_control *wbc, bool need);
 void build_free_nids(struct f2fs_sb_info *sbi, bool sync, bool mount);
 bool alloc_nid(struct f2fs_sb_info *sbi, nid_t *nid);
 void alloc_nid_done(struct f2fs_sb_info *sbi, nid_t nid);
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index d53fe62..210ec25 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1326,7 +1326,7 @@ static struct page *last_fsync_dnode(struct f2fs_sb_info *sbi, nid_t ino)
 }
 
 static int __write_node_page(struct page *page, bool atomic, bool *submitted,
-				struct writeback_control *wbc)
+				struct writeback_control *wbc, bool need)
 {
 	struct f2fs_sb_info *sbi = F2FS_P_SB(page);
 	nid_t nid;
@@ -1387,6 +1387,8 @@ static int __write_node_page(struct page *page, bool atomic, bool *submitted,
 	}
 
 	unlock_page(page);
+	if (need)
+		f2fs_balance_fs(sbi, false);
 
 	if (unlikely(f2fs_cp_error(sbi))) {
 		f2fs_submit_merged_write(sbi, NODE);
@@ -1405,7 +1407,7 @@ static int __write_node_page(struct page *page, bool atomic, bool *submitted,
 static int f2fs_write_node_page(struct page *page,
 				struct writeback_control *wbc)
 {
-	return __write_node_page(page, false, NULL, wbc);
+	return __write_node_page(page, false, NULL, wbc, false);
 }
 
 int fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
@@ -1493,7 +1495,7 @@ int fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
 
 			ret = __write_node_page(page, atomic &&
 						page == last_page,
-						&submitted, wbc);
+						&submitted, wbc, true);
 			if (ret) {
 				unlock_page(page);
 				f2fs_put_page(last_page, 0);
@@ -1530,7 +1532,7 @@ int fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
 	return ret ? -EIO: 0;
 }
 
-int sync_node_pages(struct f2fs_sb_info *sbi, struct writeback_control *wbc)
+int sync_node_pages(struct f2fs_sb_info *sbi, struct writeback_control *wbc, bool need)
 {
 	pgoff_t index, end;
 	struct pagevec pvec;
@@ -1608,7 +1610,7 @@ int sync_node_pages(struct f2fs_sb_info *sbi, struct writeback_control *wbc)
 			set_fsync_mark(page, 0);
 			set_dentry_mark(page, 0);
 
-			ret = __write_node_page(page, false, &submitted, wbc);
+			ret = __write_node_page(page, false, &submitted, wbc, need);
 			if (ret)
 				unlock_page(page);
 			else if (submitted)
@@ -1697,7 +1699,7 @@ static int f2fs_write_node_pages(struct address_space *mapping,
 	diff = nr_pages_to_write(sbi, NODE, wbc);
 	wbc->sync_mode = WB_SYNC_NONE;
 	blk_start_plug(&plug);
-	sync_node_pages(sbi, wbc);
+	sync_node_pages(sbi, wbc, true);
 	blk_finish_plug(&plug);
 	wbc->nr_to_write = max((long)0, wbc->nr_to_write - diff);
 	return 0;
-- 
1.8.5.2