fuse: remove useless IOCB_DIRECT in fuse_direct_read/write_iter

Commit 23c94e1 ("fuse: Switch to using async direct IO
for FOPEN_DIRECT_IO") gave the async direct IO code path in the
fuse_direct_read_iter() and fuse_direct_write_iter(). But since
these two functions are only called under FOPEN_DIRECT_IO is set,
it seems that we can also use the async direct IO even the flag
IOCB_DIRECT is not set to enjoy the async direct IO method. Also
move the definition of fuse_io_priv to where it is used in fuse_
direct_write_iter.

Signed-off-by: yangyun <yangyun50@huawei.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

fs/fuse/file.c

@@ -1650,7 +1650,7 @@ static ssize_t fuse_direct_read_iter(struct kiocb *iocb, struct iov_iter *to)
 {
 	ssize_t res;
 
-	if (!is_sync_kiocb(iocb) && iocb->ki_flags & IOCB_DIRECT) {
+	if (!is_sync_kiocb(iocb)) {
 		res = fuse_direct_IO(iocb, to);
 	} else {
 		struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(iocb);
@@ -1664,17 +1664,18 @@ static ssize_t fuse_direct_read_iter(struct kiocb *iocb, struct iov_iter *to)
 static ssize_t fuse_direct_write_iter(struct kiocb *iocb, struct iov_iter *from)
 {
 	struct inode *inode = file_inode(iocb->ki_filp);
-	struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(iocb);
 	ssize_t res;
 	bool exclusive;
 
 	fuse_dio_lock(iocb, from, &exclusive);
 	res = generic_write_checks(iocb, from);
 	if (res > 0) {
 		task_io_account_write(res);
-		if (!is_sync_kiocb(iocb) && iocb->ki_flags & IOCB_DIRECT) {
+		if (!is_sync_kiocb(iocb)) {
 			res = fuse_direct_IO(iocb, from);
 		} else {
+			struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(iocb);
+
 			res = fuse_direct_io(&io, from, &iocb->ki_pos,
 					     FUSE_DIO_WRITE);
 			fuse_write_update_attr(inode, iocb->ki_pos, res);