io_uring: don't duplicate ->file check in sfr

IORING_OP_SYNC_FILE_RANGE is marked as .needs_file, so the common path
will take care of assigning and validating req->file, no need to
duplicate it in io_sfr_prep().
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

fs/io_uring.c

@@ -4599,9 +4599,6 @@ static int io_sfr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 	struct io_ring_ctx *ctx = req->ctx;
 
-	if (!req->file)
-		return -EBADF;
-
 	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
 		return -EINVAL;
 	if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))