4 files changed, 34 insertions, 8 deletions

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index b0c923aef229..598bfa617a7e 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -134,7 +134,7 @@ void f2fs_submit_merged_bio(struct f2fs_sb_info *sbi,
 
 	io = is_read_io(rw) ? &sbi->read_io : &sbi->write_io[btype];
 
-	mutex_lock(&io->io_mutex);
+	down_write(&io->io_rwsem);
 
 	/* change META to META_FLUSH in the checkpoint procedure */
 	if (type >= META_FLUSH) {
@@ -142,7 +142,7 @@ void f2fs_submit_merged_bio(struct f2fs_sb_info *sbi,
 		io->fio.rw = WRITE_FLUSH_FUA | REQ_META | REQ_PRIO;
 	}
 	__submit_merged_bio(io);
-	mutex_unlock(&io->io_mutex);
+	up_write(&io->io_rwsem);
 }
 
 /*
@@ -180,7 +180,7 @@ void f2fs_submit_page_mbio(struct f2fs_sb_info *sbi, struct page *page,
 
 	verify_block_addr(sbi, blk_addr);
 
-	mutex_lock(&io->io_mutex);
+	down_write(&io->io_rwsem);
 
 	if (!is_read)
 		inc_page_count(sbi, F2FS_WRITEBACK);
@@ -204,7 +204,7 @@ alloc_new:
 
 	io->last_block_in_bio = blk_addr;
 
-	mutex_unlock(&io->io_mutex);
+	up_write(&io->io_rwsem);
 	trace_f2fs_submit_page_mbio(page, fio->rw, fio->type, blk_addr);
 }
 
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index f83433e4b043..1e3d869b60cd 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -394,7 +394,7 @@ struct f2fs_bio_info {
 	struct bio *bio;		/* bios to merge */
 	sector_t last_block_in_bio;	/* last block number */
 	struct f2fs_io_info fio;	/* store buffered io info. */
-	struct mutex io_mutex;		/* mutex for bio */
+	struct rw_semaphore io_rwsem;	/* blocking op for bio */
 };
 
 struct f2fs_sb_info {
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index e7ff23a536a4..570ab9a084c5 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -1046,12 +1046,38 @@ void rewrite_node_page(struct f2fs_sb_info *sbi,
 	mutex_unlock(&curseg->curseg_mutex);
 }
 
+static inline bool is_merged_page(struct f2fs_sb_info *sbi,
+					struct page *page, enum page_type type)
+{
+	enum page_type btype = PAGE_TYPE_OF_BIO(type);
+	struct f2fs_bio_info *io = &sbi->write_io[btype];
+	struct bio *bio = io->bio;
+	struct bio_vec *bvec;
+	int i;
+
+	down_read(&io->io_rwsem);
+	if (!bio)
+		goto out;
+
+	bio_for_each_segment_all(bvec, bio, i) {
+		if (page == bvec->bv_page) {
+			up_read(&io->io_rwsem);
+			return true;
+		}
+	}
+
+out:
+	up_read(&io->io_rwsem);
+	return false;
+}
+
 void f2fs_wait_on_page_writeback(struct page *page,
 				enum page_type type)
 {
 	struct f2fs_sb_info *sbi = F2FS_SB(page->mapping->host->i_sb);
 	if (PageWriteback(page)) {
-		f2fs_submit_merged_bio(sbi, type, WRITE);
+		if (is_merged_page(sbi, page, type))
+			f2fs_submit_merged_bio(sbi, type, WRITE);
 		wait_on_page_writeback(page);
 	}
 }
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 89ea046c846d..959834066d60 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -920,11 +920,11 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
 	sbi->por_doing = false;
 	spin_lock_init(&sbi->stat_lock);
 
-	mutex_init(&sbi->read_io.io_mutex);
+	init_rwsem(&sbi->read_io.io_rwsem);
 	sbi->read_io.sbi = sbi;
 	sbi->read_io.bio = NULL;
 	for (i = 0; i < NR_PAGE_TYPE; i++) {
-		mutex_init(&sbi->write_io[i].io_mutex);
+		init_rwsem(&sbi->write_io[i].io_rwsem);
 		sbi->write_io[i].sbi = sbi;
 		sbi->write_io[i].bio = NULL;
 	}