io_uring: handle completions in the core

Normally request handlers complete requests themselves, if they don't
return an error. For the latter case, the core will complete it for
them.

This is unhandy for pushing opcode handlers further out, as we don't
want a bunch of inline completion code and we don't want to make the
completion path slower than it is now.

Let the core handle any completion, unless the handler explicitly
asks us not to.
Signed-off-by: Jens Axboe <axboe@kernel.dk>

io_uring/io_uring.c

@@ -625,7 +625,6 @@ static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
 					 bool cancel_all);
 static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd);
 
-static void __io_req_complete_post(struct io_kiocb *req, s32 res, u32 cflags);
 static void io_dismantle_req(struct io_kiocb *req);
 static void io_queue_linked_timeout(struct io_kiocb *req);
 static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
@@ -1126,7 +1125,7 @@ static inline void req_set_fail(struct io_kiocb *req)
 static inline void req_fail_link_node(struct io_kiocb *req, int res)
 {
 	req_set_fail(req);
-	req->cqe.res = res;
+	io_req_set_res(req, res, 0);
 }
 
 static inline void io_req_add_to_cache(struct io_kiocb *req, struct io_ring_ctx *ctx)
@@ -1855,50 +1854,37 @@ static void __io_req_complete_put(struct io_kiocb *req)
 	}
 }
 
-static void __io_req_complete_post(struct io_kiocb *req, s32 res,
-				   u32 cflags)
+static void __io_req_complete_post(struct io_kiocb *req)
 {
-	if (!(req->flags & REQ_F_CQE_SKIP)) {
-		req->cqe.res = res;
-		req->cqe.flags = cflags;
+	if (!(req->flags & REQ_F_CQE_SKIP))
 		__io_fill_cqe_req(req->ctx, req);
-	}
 	__io_req_complete_put(req);
 }
 
-static void io_req_complete_post(struct io_kiocb *req, s32 res, u32 cflags)
+static void io_req_complete_post(struct io_kiocb *req)
 {
 	struct io_ring_ctx *ctx = req->ctx;
 
 	spin_lock(&ctx->completion_lock);
-	__io_req_complete_post(req, res, cflags);
+	__io_req_complete_post(req);
 	io_commit_cqring(ctx);
 	spin_unlock(&ctx->completion_lock);
 	io_cqring_ev_posted(ctx);
 }
 
-static inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags,
-				     s32 res, u32 cflags)
+static inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags)
 {
-	if (issue_flags & IO_URING_F_COMPLETE_DEFER) {
-		io_req_set_res(req, res, cflags);
+	if (issue_flags & IO_URING_F_COMPLETE_DEFER)
 		req->flags |= REQ_F_COMPLETE_INLINE;
-	} else {
-		io_req_complete_post(req, res, cflags);
-	}
-}
-
-static inline void io_req_complete(struct io_kiocb *req, s32 res)
-{
-	if (res < 0)
-		req_set_fail(req);
-	__io_req_complete(req, 0, res, 0);
+	else
+		io_req_complete_post(req);
 }
 
 static void io_req_complete_failed(struct io_kiocb *req, s32 res)
 {
 	req_set_fail(req);
-	io_req_complete_post(req, res, io_put_kbuf(req, IO_URING_F_UNLOCKED));
+	io_req_set_res(req, res, io_put_kbuf(req, IO_URING_F_UNLOCKED));
+	io_req_complete_post(req);
 }
 
 /*
@@ -2071,7 +2057,8 @@ static void io_fail_links(struct io_kiocb *req)
 			link->flags |= REQ_F_CQE_SKIP;
 		else
 			link->flags &= ~REQ_F_CQE_SKIP;
-		__io_req_complete_post(link, res, 0);
+		io_req_set_res(link, res, 0);
+		__io_req_complete_post(link);
 		link = nxt;
 	}
 }
@@ -2185,11 +2172,12 @@ static void handle_prev_tw_list(struct io_wq_work_node *node,
 			if (unlikely(!*uring_locked))
 				spin_lock(&(*ctx)->completion_lock);
 		}
-		if (likely(*uring_locked))
+		if (likely(*uring_locked)) {
 			req->io_task_work.func(req, uring_locked);
-		else
-			__io_req_complete_post(req, req->cqe.res,
-						io_put_kbuf_comp(req));
+		} else {
+			req->cqe.flags = io_put_kbuf_comp(req);
+			__io_req_complete_post(req);
+		}
 		node = next;
 	} while (node);
 
@@ -2317,13 +2305,12 @@ static void io_req_task_prio_work_add(struct io_kiocb *req)
 
 static void io_req_tw_post(struct io_kiocb *req, bool *locked)
 {
-	io_req_complete_post(req, req->cqe.res, req->cqe.flags);
+	io_req_complete_post(req);
 }
 
 static void io_req_tw_post_queue(struct io_kiocb *req, s32 res, u32 cflags)
 {
-	req->cqe.res = res;
-	req->cqe.flags = cflags;
+	io_req_set_res(req, res, cflags);
 	req->io_task_work.func = io_req_tw_post;
 	io_req_task_work_add(req);
 }
@@ -2347,7 +2334,7 @@ static void io_req_task_submit(struct io_kiocb *req, bool *locked)
 
 static void io_req_task_queue_fail(struct io_kiocb *req, int ret)
 {
-	req->cqe.res = ret;
+	io_req_set_res(req, ret, 0);
 	req->io_task_work.func = io_req_task_cancel;
 	io_req_task_work_add(req);
 }
@@ -2741,15 +2728,13 @@ static bool __io_complete_rw_common(struct io_kiocb *req, long res)
 
 static inline void io_req_task_complete(struct io_kiocb *req, bool *locked)
 {
-	int res = req->cqe.res;
-
 	if (*locked) {
-		io_req_set_res(req, res, io_put_kbuf(req, 0));
+		req->cqe.flags |= io_put_kbuf(req, 0);
 		req->flags |= REQ_F_COMPLETE_INLINE;
 		io_req_add_compl_list(req);
 	} else {
-		io_req_complete_post(req, res,
-					io_put_kbuf(req, IO_URING_F_UNLOCKED));
+		req->cqe.flags |= io_put_kbuf(req, IO_URING_F_UNLOCKED);
+		io_req_complete_post(req);
 	}
 }
 
@@ -2758,8 +2743,8 @@ static void __io_complete_rw(struct io_kiocb *req, long res,
 {
 	if (__io_complete_rw_common(req, res))
 		return;
-	__io_req_complete(req, issue_flags, req->cqe.res,
-				io_put_kbuf(req, issue_flags));
+	io_req_set_res(req, req->cqe.res, io_put_kbuf(req, issue_flags));
+	__io_req_complete(req, issue_flags);
 }
 
 static void io_complete_rw(struct kiocb *kiocb, long res)
@@ -2769,7 +2754,7 @@ static void io_complete_rw(struct kiocb *kiocb, long res)
 
 	if (__io_complete_rw_common(req, res))
 		return;
-	req->cqe.res = res;
+	io_req_set_res(req, res, 0);
 	req->io_task_work.func = io_req_task_complete;
 	io_req_task_prio_work_add(req);
 }
@@ -3745,7 +3730,7 @@ static int io_read(struct io_kiocb *req, unsigned int issue_flags)
 		 */
 		ret = io_iter_do_read(rw, &s->iter);
 		if (ret == -EIOCBQUEUED)
-			return 0;
+			return IOU_ISSUE_SKIP_COMPLETE;
 		/* we got some bytes, but not all. retry. */
 		kiocb->ki_flags &= ~IOCB_WAITQ;
 		iov_iter_restore(&s->iter, &s->iter_state);
@@ -3756,7 +3741,7 @@ static int io_read(struct io_kiocb *req, unsigned int issue_flags)
 	/* it's faster to check here then delegate to kfree */
 	if (iovec)
 		kfree(iovec);
-	return 0;
+	return IOU_ISSUE_SKIP_COMPLETE;
 }
 
 static int io_write(struct io_kiocb *req, unsigned int issue_flags)
@@ -3850,6 +3835,7 @@ static int io_write(struct io_kiocb *req, unsigned int issue_flags)
 			goto copy_iov;
 done:
 		kiocb_done(req, ret2, issue_flags);
+		ret = IOU_ISSUE_SKIP_COMPLETE;
 	} else {
 copy_iov:
 		iov_iter_restore(&s->iter, &s->iter_state);
@@ -3906,8 +3892,8 @@ static int io_renameat(struct io_kiocb *req, unsigned int issue_flags)
 				ren->newpath, ren->flags);
 
 	req->flags &= ~REQ_F_NEED_CLEANUP;
-	io_req_complete(req, ret);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static void io_renameat_cleanup(struct io_kiocb *req)
@@ -3934,7 +3920,7 @@ static void io_xattr_finish(struct io_kiocb *req, int ret)
 	req->flags &= ~REQ_F_NEED_CLEANUP;
 
 	io_xattr_cleanup(req);
-	io_req_complete(req, ret);
+	io_req_set_res(req, ret, 0);
 }
 
 static int __io_getxattr_prep(struct io_kiocb *req,
@@ -4015,7 +4001,7 @@ static int io_fgetxattr(struct io_kiocb *req, unsigned int issue_flags)
 			&ix->ctx);
 
 	io_xattr_finish(req, ret);
-	return 0;
+	return IOU_OK;
 }
 
 static int io_getxattr(struct io_kiocb *req, unsigned int issue_flags)
@@ -4043,7 +4029,7 @@ static int io_getxattr(struct io_kiocb *req, unsigned int issue_flags)
 	}
 
 	io_xattr_finish(req, ret);
-	return 0;
+	return IOU_OK;
 }
 
 static int __io_setxattr_prep(struct io_kiocb *req,
@@ -4129,8 +4115,7 @@ static int io_fsetxattr(struct io_kiocb *req, unsigned int issue_flags)
 
 	ret = __io_setxattr(req, issue_flags, &req->file->f_path);
 	io_xattr_finish(req, ret);
-
-	return 0;
+	return IOU_OK;
 }
 
 static int io_setxattr(struct io_kiocb *req, unsigned int issue_flags)
@@ -4155,7 +4140,7 @@ static int io_setxattr(struct io_kiocb *req, unsigned int issue_flags)
 	}
 
 	io_xattr_finish(req, ret);
-	return 0;
+	return IOU_OK;
 }
 
 static int io_unlinkat_prep(struct io_kiocb *req,
@@ -4198,8 +4183,8 @@ static int io_unlinkat(struct io_kiocb *req, unsigned int issue_flags)
 		ret = do_unlinkat(un->dfd, un->filename);
 
 	req->flags &= ~REQ_F_NEED_CLEANUP;
-	io_req_complete(req, ret);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static void io_unlinkat_cleanup(struct io_kiocb *req)
@@ -4243,8 +4228,8 @@ static int io_mkdirat(struct io_kiocb *req, unsigned int issue_flags)
 	ret = do_mkdirat(mkd->dfd, mkd->filename, mkd->mode);
 
 	req->flags &= ~REQ_F_NEED_CLEANUP;
-	io_req_complete(req, ret);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static void io_mkdirat_cleanup(struct io_kiocb *req)
@@ -4294,8 +4279,8 @@ static int io_symlinkat(struct io_kiocb *req, unsigned int issue_flags)
 	ret = do_symlinkat(sl->oldpath, sl->new_dfd, sl->newpath);
 
 	req->flags &= ~REQ_F_NEED_CLEANUP;
-	io_req_complete(req, ret);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int io_linkat_prep(struct io_kiocb *req,
@@ -4341,8 +4326,8 @@ static int io_linkat(struct io_kiocb *req, unsigned int issue_flags)
 				lnk->newpath, lnk->flags);
 
 	req->flags &= ~REQ_F_NEED_CLEANUP;
-	io_req_complete(req, ret);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static void io_link_cleanup(struct io_kiocb *req)
@@ -4393,7 +4378,7 @@ void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2)
 	io_req_set_res(req, 0, ret);
 	if (req->ctx->flags & IORING_SETUP_CQE32)
 		io_req_set_cqe32_extra(req, res2, 0);
-	io_req_complete(req, ret);
+	__io_req_complete(req, 0);
 }
 EXPORT_SYMBOL_GPL(io_uring_cmd_done);
 
@@ -4450,9 +4435,12 @@ static int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
 		return -EAGAIN;
 	}
 
-	if (ret != -EIOCBQUEUED)
+	if (ret != -EIOCBQUEUED) {
 		io_uring_cmd_done(ioucmd, ret, 0);
-	return 0;
+		return IOU_OK;
+	}
+
+	return IOU_ISSUE_SKIP_COMPLETE;
 }
 
 static int __io_splice_prep(struct io_kiocb *req,
@@ -4505,8 +4493,8 @@ static int io_tee(struct io_kiocb *req, unsigned int issue_flags)
 done:
 	if (ret != sp->len)
 		req_set_fail(req);
-	__io_req_complete(req, 0, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
@@ -4550,8 +4538,8 @@ static int io_splice(struct io_kiocb *req, unsigned int issue_flags)
 done:
 	if (ret != sp->len)
 		req_set_fail(req);
-	__io_req_complete(req, 0, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int io_nop_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
@@ -4564,8 +4552,8 @@ static int io_nop_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
  */
 static int io_nop(struct io_kiocb *req, unsigned int issue_flags)
 {
-	__io_req_complete(req, issue_flags, 0, 0);
-	return 0;
+	io_req_set_res(req, 0, 0);
+	return IOU_OK;
 }
 
 static int io_msg_ring_prep(struct io_kiocb *req,
@@ -4609,11 +4597,11 @@ static int io_msg_ring(struct io_kiocb *req, unsigned int issue_flags)
 done:
 	if (ret < 0)
 		req_set_fail(req);
-	__io_req_complete(req, issue_flags, ret, 0);
+	io_req_set_res(req, ret, 0);
 	/* put file to avoid an attempt to IOPOLL the req */
 	io_put_file(req->file);
 	req->file = NULL;
-	return 0;
+	return IOU_OK;
 }
 
 static int io_fsync_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
@@ -4644,8 +4632,8 @@ static int io_fsync(struct io_kiocb *req, unsigned int issue_flags)
 
 	ret = vfs_fsync_range(req->file, sync->off, end > 0 ? end : LLONG_MAX,
 				sync->flags & IORING_FSYNC_DATASYNC);
-	io_req_complete(req, ret);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int io_fallocate_prep(struct io_kiocb *req,
@@ -4673,8 +4661,8 @@ static int io_fallocate(struct io_kiocb *req, unsigned int issue_flags)
 	ret = vfs_fallocate(req->file, sync->mode, sync->off, sync->len);
 	if (ret >= 0)
 		fsnotify_modify(req->file);
-	io_req_complete(req, ret);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
@@ -4855,8 +4843,8 @@ static int io_openat2(struct io_kiocb *req, unsigned int issue_flags)
 	req->flags &= ~REQ_F_NEED_CLEANUP;
 	if (ret < 0)
 		req_set_fail(req);
-	__io_req_complete(req, issue_flags, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int io_openat(struct io_kiocb *req, unsigned int issue_flags)
@@ -4951,9 +4939,10 @@ static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
 		req_set_fail(req);
 
 	/* complete before unlock, IOPOLL may need the lock */
-	__io_req_complete(req, issue_flags, ret, 0);
+	io_req_set_res(req, ret, 0);
+	__io_req_complete(req, issue_flags);
 	io_ring_submit_unlock(ctx, issue_flags);
-	return 0;
+	return IOU_ISSUE_SKIP_COMPLETE;
 }
 
 static int io_provide_buffers_prep(struct io_kiocb *req,
@@ -5117,9 +5106,10 @@ static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
 	if (ret < 0)
 		req_set_fail(req);
 	/* complete before unlock, IOPOLL may need the lock */
-	__io_req_complete(req, issue_flags, ret, 0);
+	io_req_set_res(req, ret, 0);
+	__io_req_complete(req, issue_flags);
 	io_ring_submit_unlock(ctx, issue_flags);
-	return 0;
+	return IOU_ISSUE_SKIP_COMPLETE;
 }
 
 static int io_epoll_ctl_prep(struct io_kiocb *req,
@@ -5162,8 +5152,8 @@ static int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
 
 	if (ret < 0)
 		req_set_fail(req);
-	__io_req_complete(req, issue_flags, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 #else
 	return -EOPNOTSUPP;
 #endif
@@ -5196,8 +5186,8 @@ static int io_madvise(struct io_kiocb *req, unsigned int issue_flags)
 		return -EAGAIN;
 
 	ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice);
-	io_req_complete(req, ret);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 #else
 	return -EOPNOTSUPP;
 #endif
@@ -5235,8 +5225,8 @@ static int io_fadvise(struct io_kiocb *req, unsigned int issue_flags)
 	ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice);
 	if (ret < 0)
 		req_set_fail(req);
-	__io_req_complete(req, issue_flags, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
@@ -5279,8 +5269,8 @@ static int io_statx(struct io_kiocb *req, unsigned int issue_flags)
 		return -EAGAIN;
 
 	ret = do_statx(sx->dfd, sx->filename, sx->flags, sx->mask, sx->buffer);
-	io_req_complete(req, ret);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static void io_statx_cleanup(struct io_kiocb *req)
@@ -5350,8 +5340,8 @@ static int io_close(struct io_kiocb *req, unsigned int issue_flags)
 err:
 	if (ret < 0)
 		req_set_fail(req);
-	__io_req_complete(req, issue_flags, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int io_sfr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
@@ -5377,8 +5367,8 @@ static int io_sync_file_range(struct io_kiocb *req, unsigned int issue_flags)
 		return -EAGAIN;
 
 	ret = sync_file_range(req->file, sync->off, sync->len, sync->flags);
-	io_req_complete(req, ret);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 #if defined(CONFIG_NET)
@@ -5409,8 +5399,8 @@ static int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
 		return -ENOTSOCK;
 
 	ret = __sys_shutdown_sock(sock, shutdown->how);
-	io_req_complete(req, ret);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static bool io_net_retry(struct socket *sock, int flags)
@@ -5548,8 +5538,8 @@ static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
 		ret += sr->done_io;
 	else if (sr->done_io)
 		ret = sr->done_io;
-	__io_req_complete(req, issue_flags, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int io_send(struct io_kiocb *req, unsigned int issue_flags)
@@ -5605,8 +5595,8 @@ static int io_send(struct io_kiocb *req, unsigned int issue_flags)
 		ret += sr->done_io;
 	else if (sr->done_io)
 		ret = sr->done_io;
-	__io_req_complete(req, issue_flags, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
@@ -5805,8 +5795,8 @@ static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
 	cflags = io_put_kbuf(req, issue_flags);
 	if (kmsg->msg.msg_inq)
 		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
-	__io_req_complete(req, issue_flags, ret, cflags);
-	return 0;
+	io_req_set_res(req, ret, cflags);
+	return IOU_OK;
 }
 
 static int io_recv(struct io_kiocb *req, unsigned int issue_flags)
@@ -5881,8 +5871,8 @@ static int io_recv(struct io_kiocb *req, unsigned int issue_flags)
 	cflags = io_put_kbuf(req, issue_flags);
 	if (msg.msg_inq)
 		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
-	__io_req_complete(req, issue_flags, ret, cflags);
-	return 0;
+	io_req_set_res(req, ret, cflags);
+	return IOU_OK;
 }
 
 static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
@@ -5948,7 +5938,7 @@ static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
 			 */
 			if ((req->flags & IO_APOLL_MULTI_POLLED) ==
 			    IO_APOLL_MULTI_POLLED)
-				ret = 0;
+				ret = IOU_ISSUE_SKIP_COMPLETE;
 			return ret;
 		}
 		if (ret == -ERESTARTSYS)
@@ -5963,8 +5953,8 @@ static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
 	}
 
 	if (!(req->flags & REQ_F_APOLL_MULTISHOT)) {
-		__io_req_complete(req, issue_flags, ret, 0);
-		return 0;
+		io_req_set_res(req, ret, 0);
+		return IOU_OK;
 	}
 	if (ret >= 0) {
 		bool filled;
@@ -6034,8 +6024,8 @@ static int io_socket(struct io_kiocb *req, unsigned int issue_flags)
 		ret = io_fixed_fd_install(req, issue_flags, file,
 					    sock->file_slot);
 	}
-	__io_req_complete(req, issue_flags, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int io_connect_prep_async(struct io_kiocb *req)
@@ -6096,8 +6086,8 @@ static int io_connect(struct io_kiocb *req, unsigned int issue_flags)
 out:
 	if (ret < 0)
 		req_set_fail(req);
-	__io_req_complete(req, issue_flags, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 #else /* !CONFIG_NET */
 #define IO_NETOP_FN(op)							\
@@ -6328,7 +6318,8 @@ static void io_poll_task_func(struct io_kiocb *req, bool *locked)
 	io_poll_remove_entries(req);
 	spin_lock(&ctx->completion_lock);
 	hash_del(&req->hash_node);
-	__io_req_complete_post(req, req->cqe.res, 0);
+	req->cqe.flags = 0;
+	__io_req_complete_post(req);
 	io_commit_cqring(ctx);
 	spin_unlock(&ctx->completion_lock);
 	io_cqring_ev_posted(ctx);
@@ -6357,7 +6348,7 @@ static void io_apoll_task_func(struct io_kiocb *req, bool *locked)
 static void __io_poll_execute(struct io_kiocb *req, int mask,
 			      __poll_t __maybe_unused events)
 {
-	req->cqe.res = mask;
+	io_req_set_res(req, mask, 0);
 	/*
 	 * This is useful for poll that is armed on behalf of another
 	 * request, and where the wakeup path could be on a different
@@ -6810,12 +6801,16 @@ static int io_poll_add(struct io_kiocb *req, unsigned int issue_flags)
 	ipt.pt._qproc = io_poll_queue_proc;
 
 	ret = __io_arm_poll_handler(req, poll, &ipt, poll->events);
-	if (!ret && ipt.error)
+	if (ret) {
+		io_req_set_res(req, ret, 0);
+		return IOU_OK;
+	}
+	if (ipt.error) {
 		req_set_fail(req);
-	ret = ret ?: ipt.error;
-	if (ret)
-		__io_req_complete(req, issue_flags, ret, 0);
-	return 0;
+		return ipt.error;
+	}
+
+	return IOU_ISSUE_SKIP_COMPLETE;
 }
 
 static int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags)
@@ -6850,20 +6845,22 @@ static int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags)
 
 		ret2 = io_poll_add(preq, issue_flags);
 		/* successfully updated, don't complete poll request */
-		if (!ret2)
+		if (!ret2 || ret2 == -EIOCBQUEUED)
 			goto out;
 	}
 
 	req_set_fail(preq);
-	preq->cqe.res = -ECANCELED;
+	io_req_set_res(preq, -ECANCELED, 0);
 	locked = !(issue_flags & IO_URING_F_UNLOCKED);
 	io_req_task_complete(preq, &locked);
 out:
-	if (ret < 0)
+	if (ret < 0) {
 		req_set_fail(req);
+		return ret;
+	}
 	/* complete update request, we're done with it */
-	__io_req_complete(req, issue_flags, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
@@ -6884,7 +6881,7 @@ static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
 	if (!(data->flags & IORING_TIMEOUT_ETIME_SUCCESS))
 		req_set_fail(req);
 
-	req->cqe.res = -ETIME;
+	io_req_set_res(req, -ETIME, 0);
 	req->io_task_work.func = io_req_task_complete;
 	io_req_task_work_add(req);
 	return HRTIMER_NORESTART;
@@ -7069,8 +7066,8 @@ static int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
 
 	if (ret < 0)
 		req_set_fail(req);
-	io_req_complete_post(req, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int __io_timeout_prep(struct io_kiocb *req,
@@ -7191,7 +7188,7 @@ static int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
 	data->timer.function = io_timeout_fn;
 	hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
 	spin_unlock_irq(&ctx->timeout_lock);
-	return 0;
+	return IOU_ISSUE_SKIP_COMPLETE;
 }
 
 static bool io_cancel_cb(struct io_wq_work *work, void *data)
@@ -7359,8 +7356,8 @@ static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
 done:
 	if (ret < 0)
 		req_set_fail(req);
-	io_req_complete_post(req, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int io_files_update_prep(struct io_kiocb *req,
@@ -7445,8 +7442,8 @@ static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
 
 	if (ret < 0)
 		req_set_fail(req);
-	__io_req_complete(req, issue_flags, ret, 0);
-	return 0;
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
 }
 
 static int io_req_prep_async(struct io_kiocb *req)
@@ -7590,8 +7587,12 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
 
 	if (creds)
 		revert_creds(creds);
-	if (ret)
+
+	if (ret == IOU_OK)
+		__io_req_complete(req, issue_flags);
+	else if (ret != IOU_ISSUE_SKIP_COMPLETE)
 		return ret;
+
 	/* If the op doesn't have a file, we're not polling for it */
 	if ((req->ctx->flags & IORING_SETUP_IOPOLL) && req->file)
 		io_iopoll_req_issued(req, issue_flags);
@@ -7668,7 +7669,7 @@ static void io_wq_submit_work(struct io_wq_work *work)
 	} while (1);
 
 	/* avoid locking problems by failing it from a clean context */
-	if (ret)
+	if (ret < 0)
 		io_req_task_queue_fail(req, ret);
 }
 
@@ -7745,10 +7746,12 @@ static void io_req_task_link_timeout(struct io_kiocb *req, bool *locked)
 
 			ret = io_try_cancel(req, &cd);
 		}
-		io_req_complete_post(req, ret ?: -ETIME, 0);
+		io_req_set_res(req, ret ?: -ETIME, 0);
+		io_req_complete_post(req);
 		io_put_req(prev);
 	} else {
-		io_req_complete_post(req, -ETIME, 0);
+		io_req_set_res(req, -ETIME, 0);
+		io_req_complete_post(req);
 	}
 }
 

io_uring/io_uring.h

@@ -4,6 +4,11 @@
 #include <linux/errno.h>
 #include "io_uring_types.h"
 
+enum {
+	IOU_OK			= 0,
+	IOU_ISSUE_SKIP_COMPLETE	= -EIOCBQUEUED,
+};
+
 static inline void io_req_set_res(struct io_kiocb *req, s32 res, u32 cflags)
 {
 	req->cqe.res = res;