From cf0dd9527eee5d6d183fa724fdee6a128cb17b8d Mon Sep 17 00:00:00 2001 From: Dylan Yudaken Date: Mon, 4 Jul 2022 07:01:06 -0700 Subject: [PATCH] io_uring: disable multishot recvmsg recvmsg has semantics that do not make it trivial to extend to multishot. Specifically it has user pointers and returns data in the original parameter. In order to make this API useful these will need to be somehow included with the provided buffers. For now remove multishot for recvmsg as it is not useful. Signed-off-by: Dylan Yudaken Link: https://lore.kernel.org/r/20220704140106.200167-1-dylany@fb.com Signed-off-by: Jens Axboe --- io_uring/net.c | 29 ++++++++++------------------- 1 file changed, 10 insertions(+), 19 deletions(-) diff --git a/io_uring/net.c b/io_uring/net.c index cb08a4b62840..6679069eeef1 100644 --- a/io_uring/net.c +++ b/io_uring/net.c @@ -409,6 +409,8 @@ int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) if (sr->msg_flags & MSG_ERRQUEUE) req->flags |= REQ_F_CLEAR_POLLIN; if (sr->flags & IORING_RECV_MULTISHOT) { + if (req->opcode == IORING_OP_RECVMSG) + return -EINVAL; if (!(req->flags & REQ_F_BUFFER_SELECT)) return -EINVAL; if (sr->msg_flags & MSG_WAITALL) @@ -435,7 +437,7 @@ static inline void io_recv_prep_retry(struct io_kiocb *req) } /* - * Finishes io_recv and io_recvmsg. + * Finishes io_recv * * Returns true if it is actually finished, or false if it should run * again (for multishot). @@ -477,7 +479,6 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) unsigned flags; int ret, min_ret = 0; bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK; - size_t len = sr->len; sock = sock_from_file(req->file); if (unlikely(!sock)) @@ -496,17 +497,16 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) (sr->flags & IORING_RECVSEND_POLL_FIRST)) return io_setup_async_msg(req, kmsg); -retry_multishot: if (io_do_buffer_select(req)) { void __user *buf; - buf = io_buffer_select(req, &len, issue_flags); + buf = io_buffer_select(req, &sr->len, issue_flags); if (!buf) return -ENOBUFS; kmsg->fast_iov[0].iov_base = buf; - kmsg->fast_iov[0].iov_len = len; + kmsg->fast_iov[0].iov_len = sr->len; iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov, 1, - len); + sr->len); } flags = sr->msg_flags; @@ -518,15 +518,8 @@ retry_multishot: kmsg->msg.msg_get_inq = 1; ret = __sys_recvmsg_sock(sock, &kmsg->msg, sr->umsg, kmsg->uaddr, flags); if (ret < min_ret) { - if (ret == -EAGAIN && force_nonblock) { - ret = io_setup_async_msg(req, kmsg); - if (ret == -EAGAIN && (req->flags & IO_APOLL_MULTI_POLLED) == - IO_APOLL_MULTI_POLLED) { - io_kbuf_recycle(req, issue_flags); - return IOU_ISSUE_SKIP_COMPLETE; - } - return ret; - } + if (ret == -EAGAIN && force_nonblock) + return io_setup_async_msg(req, kmsg); if (ret == -ERESTARTSYS) ret = -EINTR; if (ret > 0 && io_net_retry(sock, flags)) { @@ -554,10 +547,8 @@ retry_multishot: if (kmsg->msg.msg_inq) cflags |= IORING_CQE_F_SOCK_NONEMPTY; - if (!io_recv_finish(req, &ret, cflags)) - goto retry_multishot; - - return ret; + io_req_set_res(req, ret, cflags); + return IOU_OK; } int io_recv(struct io_kiocb *req, unsigned int issue_flags) -- 2.11.0