exfat: fdatasync flag should be same like generic_write_sync()

[ Upstream commit 2f2d42a17b5a6711378d39df74f1f69a831c5d4e ]

Test: androbench by default setting, use 64GB sdcard.
 the random write speed:
	without this patch 3.5MB/s
	with this patch 7MB/s

After patch "11a347fb6cef", the random write speed decreased significantly.
the .write_iter() interface had been modified, and check the differences
with generic_file_write_iter(), when calling generic_write_sync() and
exfat_file_write_iter() to call vfs_fsync_range(), the fdatasync flag is
wrong, and make not use the fdatasync mode, and make random write speed
decreased. So use generic_write_sync() instead of vfs_fsync_range().

Fixes: 11a347fb6cef ("exfat: change to get file size from DataLength")
Signed-off-by: Zhengxu Zhang <zhengxu.zhang@unisoc.com>
Acked-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/exfat/file.c b/fs/exfat/file.c
index 841a5b18e3dfdb3566ec28ca7096a28713b17ffa..7ac5126aa4f1eabfd7f3d6ca29b0ffd98c90d52a 100644 (file)
--- a/fs/exfat/file.c
+++ b/fs/exfat/file.c
@@ -623,9 +623,8 @@ static ssize_t exfat_file_write_iter(struct kiocb *iocb, struct iov_iter *iter)
        if (pos > valid_size)
                pos = valid_size;
 
-       if (iocb_is_dsync(iocb) && iocb->ki_pos > pos) {
-               ssize_t err = vfs_fsync_range(file, pos, iocb->ki_pos - 1,
-                               iocb->ki_flags & IOCB_SYNC);
+       if (iocb->ki_pos > pos) {
+               ssize_t err = generic_write_sync(iocb, iocb->ki_pos - pos);
                if (err < 0)
                        return err;
        }