io_uring/net: remove dependency on REQ_F_PARTIAL_IO for sr->done_io

[ Upstream commit 9817ad85899fb695f875610fb743cb18cf087582 ]

Ensure that prep handlers always initialize sr->done_io before any
potential failure conditions, and with that, we now it's always been
set even for the failure case.

With that, we don't need to use the REQ_F_PARTIAL_IO flag to gate on that.
Additionally, we should not overwrite req->cqe.res unless sr->done_io is
actually positive.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: ef42b85a5609 ("io_uring/net: fix sendzc lazy wake polling")
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/io_uring/net.c b/io_uring/net.c
index 46ea09e1e38290ada1daa53946d4273a8c359fb2..d193b87d0a03b125aae83feb1a01ba5d3808de37 100644 (file)
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -359,6 +359,8 @@ int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
        struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
 
+       sr->done_io = 0;
+
        if (req->opcode == IORING_OP_SEND) {
                if (READ_ONCE(sqe->__pad3[0]))
                        return -EINVAL;
@@ -381,7 +383,6 @@ int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
        if (req->ctx->compat)
                sr->msg_flags |= MSG_CMSG_COMPAT;
 #endif
-       sr->done_io = 0;
        return 0;
 }
 
@@ -603,6 +604,8 @@ int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
        struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
 
+       sr->done_io = 0;
+
        if (unlikely(sqe->file_index || sqe->addr2))
                return -EINVAL;
 
@@ -639,7 +642,6 @@ int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
        if (req->ctx->compat)
                sr->msg_flags |= MSG_CMSG_COMPAT;
 #endif
-       sr->done_io = 0;
        sr->nr_multishot_loops = 0;
        return 0;
 }
@@ -1019,6 +1021,8 @@ int io_send_zc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
        struct io_ring_ctx *ctx = req->ctx;
        struct io_kiocb *notif;
 
+       zc->done_io = 0;
+
        if (unlikely(READ_ONCE(sqe->__pad2[0]) || READ_ONCE(sqe->addr3)))
                return -EINVAL;
        /* we don't support IOSQE_CQE_SKIP_SUCCESS just yet */
@@ -1071,8 +1075,6 @@ int io_send_zc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
        if (zc->msg_flags & MSG_DONTWAIT)
                req->flags |= REQ_F_NOWAIT;
 
-       zc->done_io = 0;
-
 #ifdef CONFIG_COMPAT
        if (req->ctx->compat)
                zc->msg_flags |= MSG_CMSG_COMPAT;
@@ -1318,7 +1320,7 @@ void io_sendrecv_fail(struct io_kiocb *req)
 {
        struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
 
-       if (req->flags & REQ_F_PARTIAL_IO)
+       if (sr->done_io)
                req->cqe.res = sr->done_io;
 
        if ((req->flags & REQ_F_NEED_CLEANUP) &&