io_uring: add allow_overflow to io_post_aux_cqe

Some use cases of io_post_aux_cqe would not want to overflow as is, but
might want to change the flags/result. For example multishot receive
requires in order CQE, and so if there is an overflow it would need to
stop receiving until the overflow is taken care of.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220630091231.1456789-8-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 745264938a489f3e7452635637d3c0ae5e59440b..523b6ebad15a302402241760636f597b78dcb1bb 100644 (file)
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -736,7 +736,8 @@ struct io_uring_cqe *__io_get_cqe(struct io_ring_ctx *ctx)
 }
 
 static bool io_fill_cqe_aux(struct io_ring_ctx *ctx,
-                           u64 user_data, s32 res, u32 cflags)
+                           u64 user_data, s32 res, u32 cflags,
+                           bool allow_overflow)
 {
        struct io_uring_cqe *cqe;
 
@@ -760,16 +761,21 @@ static bool io_fill_cqe_aux(struct io_ring_ctx *ctx,
                }
                return true;
        }
-       return io_cqring_event_overflow(ctx, user_data, res, cflags, 0, 0);
+
+       if (allow_overflow)
+               return io_cqring_event_overflow(ctx, user_data, res, cflags, 0, 0);
+
+       return false;
 }
 
 bool io_post_aux_cqe(struct io_ring_ctx *ctx,
-                    u64 user_data, s32 res, u32 cflags)
+                    u64 user_data, s32 res, u32 cflags,
+                    bool allow_overflow)
 {
        bool filled;
 
        io_cq_lock(ctx);
-       filled = io_fill_cqe_aux(ctx, user_data, res, cflags);
+       filled = io_fill_cqe_aux(ctx, user_data, res, cflags, allow_overflow);
        io_cq_unlock_post(ctx);
        return filled;
 }

diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h
index e8da70781fa34bec9faaf7e561343dc3a8552770..e022d71c177a4628b5c0ea8222f4b7521624197e 100644 (file)
--- a/io_uring/io_uring.h
+++ b/io_uring/io_uring.h
@@ -31,7 +31,8 @@ void io_req_complete_failed(struct io_kiocb *req, s32 res);
 void __io_req_complete(struct io_kiocb *req, unsigned issue_flags);
 void io_req_complete_post(struct io_kiocb *req);
 void __io_req_complete_post(struct io_kiocb *req);
-bool io_post_aux_cqe(struct io_ring_ctx *ctx, u64 user_data, s32 res, u32 cflags);
+bool io_post_aux_cqe(struct io_ring_ctx *ctx, u64 user_data, s32 res, u32 cflags,
+                    bool allow_overflow);
 void __io_commit_cqring_flush(struct io_ring_ctx *ctx);
 
 struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages);

diff --git a/io_uring/msg_ring.c b/io_uring/msg_ring.c
index 939205b30c8b627cbf159428c578eab88de36e8e..753d16734319a4dd878a4ed4ddde460e16599471 100644 (file)
--- a/io_uring/msg_ring.c
+++ b/io_uring/msg_ring.c
@@ -31,7 +31,7 @@ static int io_msg_ring_data(struct io_kiocb *req)
        if (msg->src_fd || msg->dst_fd || msg->flags)
                return -EINVAL;
 
-       if (io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0))
+       if (io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0, true))
                return 0;
 
        return -EOVERFLOW;
@@ -113,7 +113,7 @@ static int io_msg_send_fd(struct io_kiocb *req, unsigned int issue_flags)
         * completes with -EOVERFLOW, then the sender must ensure that a
         * later IORING_OP_MSG_RING delivers the message.
         */
-       if (!io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0))
+       if (!io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0, true))
                ret = -EOVERFLOW;
 out_unlock:
        io_double_unlock_ctx(ctx, target_ctx, issue_flags);

diff --git a/io_uring/net.c b/io_uring/net.c
index e4422dff07048a80515096b973379c600ec8b84c..601955fdb124f73694c3717adf7a88885a9747e9 100644 (file)
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -658,7 +658,7 @@ retry:
 
        if (ret < 0)
                return ret;
-       if (io_post_aux_cqe(ctx, req->cqe.user_data, ret, IORING_CQE_F_MORE))
+       if (io_post_aux_cqe(ctx, req->cqe.user_data, ret, IORING_CQE_F_MORE, true))
                goto retry;
        return -ECANCELED;
 }

diff --git a/io_uring/poll.c b/io_uring/poll.c
index 64d426d696abc84dac207d8a771ac396fa793bd7..e8f922a4f6d754caf1764b36fe77b8e69a255b04 100644 (file)
--- a/io_uring/poll.c
+++ b/io_uring/poll.c
@@ -243,7 +243,7 @@ static int io_poll_check_events(struct io_kiocb *req, bool *locked)
                                                    req->apoll_events);
 
                        if (!io_post_aux_cqe(ctx, req->cqe.user_data,
-                                            mask, IORING_CQE_F_MORE))
+                                            mask, IORING_CQE_F_MORE, true))
                                return -ECANCELED;
                } else {
                        ret = io_poll_issue(req, locked);

diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c
index d2e589c703d063af573d358f2dd15821d4a3cfc9..0250c13ae1cdd0f1d68ec14c6688fb7bad9bdbe2 100644 (file)
--- a/io_uring/rsrc.c
+++ b/io_uring/rsrc.c
@@ -175,10 +175,10 @@ static void __io_rsrc_put_work(struct io_rsrc_node *ref_node)
                if (prsrc->tag) {
                        if (ctx->flags & IORING_SETUP_IOPOLL) {
                                mutex_lock(&ctx->uring_lock);
-                               io_post_aux_cqe(ctx, prsrc->tag, 0, 0);
+                               io_post_aux_cqe(ctx, prsrc->tag, 0, 0, true);
                                mutex_unlock(&ctx->uring_lock);
                        } else {
-                               io_post_aux_cqe(ctx, prsrc->tag, 0, 0);
+                               io_post_aux_cqe(ctx, prsrc->tag, 0, 0, true);
                        }
                }