io_uring: remove obsolete @mm_fault

If io_submit_sqes() can't grab an mm, it fails and exits right away.
There is no need to track the fact of the failure. Remove @mm_fault.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

fs/io_uring.c

@@ -5818,7 +5818,6 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr,
 	struct io_submit_state state, *statep = NULL;
 	struct io_kiocb *link = NULL;
 	int i, submitted = 0;
-	bool mm_fault = false;
 
 	/* if we have a backlog and couldn't flush it all, return BUSY */
 	if (test_bit(0, &ctx->sq_check_overflow)) {
@@ -5872,8 +5871,7 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr,
 		}
 
 		if (io_op_defs[req->opcode].needs_mm && !*mm) {
-			mm_fault = mm_fault || !mmget_not_zero(ctx->sqo_mm);
-			if (unlikely(mm_fault)) {
+			if (unlikely(!mmget_not_zero(ctx->sqo_mm))) {
 				err = -EFAULT;
 				goto fail_req;
 			}