f2fs: fix data corruption issue with hardware encryption

Direct IO can be used in case of hardware encryption. The following
scenario results into data corruption issue in this path -

Thread A -                          Thread B-
-> write file#1 in direct IO
                                    -> GC gets kicked in
                                    -> GC submitted bio on meta mapping
				       for file#1, but pending completion
-> write file#1 again with new data
   in direct IO
                                    -> GC bio gets completed now
                                    -> GC writes old data to the new
                                       location and thus file#1 is
				       corrupted.

Fix this by submitting and waiting for pending io on meta mapping
for direct IO case in f2fs_map_blocks().

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index e38b2f69b68e..6edcf8391dd3 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -3303,6 +3303,15 @@ void f2fs_wait_on_block_writeback(struct inode *inode, block_t blkaddr)
 	}
 }
 
+void f2fs_wait_on_block_writeback_range(struct inode *inode, block_t blkaddr,
+								block_t len)
+{
+	block_t i;
+
+	for (i = 0; i < len; i++)
+		f2fs_wait_on_block_writeback(inode, blkaddr + i);
+}
+
 static int read_compacted_summaries(struct f2fs_sb_info *sbi)
 {
 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);