From patchwork Thu Jul 14 11:02:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dylan Yudaken X-Patchwork-Id: 12917712 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 281DACCA480 for ; Thu, 14 Jul 2022 11:03:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237934AbiGNLDQ (ORCPT ); Thu, 14 Jul 2022 07:03:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42966 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238571AbiGNLDN (ORCPT ); Thu, 14 Jul 2022 07:03:13 -0400 Received: from mx0a-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9DFBC57204 for ; Thu, 14 Jul 2022 04:03:11 -0700 (PDT) Received: from pps.filterd (m0089730.ppops.net [127.0.0.1]) by m0089730.ppops.net (8.17.1.5/8.17.1.5) with ESMTP id 26E6xFxW000793 for ; Thu, 14 Jul 2022 04:03:10 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=DE7JVlnFMlLBEggWShqHOB5KvbV6MgRJAuWQOUcSEPU=; b=U1aAbVxc3sqr9wr448LUcQoe3OXYdeD9nq787j0vMypXTLGIR4jWIy1PeC1sdgS+Sqrt ngvY3uwrQ6Tk0OPwpTE018OkU/qJYRtKaKoWVWZcmDrVnKuVM8YwHZubL5jvq2E/Mhof UDTufpJ5PEQXGE2wCgcatYUKwC2Nlz2NPYI= Received: from maileast.thefacebook.com ([163.114.130.16]) by m0089730.ppops.net (PPS) with ESMTPS id 3h9h5f29ew-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 14 Jul 2022 04:03:10 -0700 Received: from twshared18317.08.ash9.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.28; Thu, 14 Jul 2022 04:03:09 -0700 Received: by devbig038.lla2.facebook.com (Postfix, from userid 572232) id 2A4132FCA61E; Thu, 14 Jul 2022 04:03:03 -0700 (PDT) From: Dylan Yudaken To: Jens Axboe , Pavel Begunkov , , , , , CC: , , Dylan Yudaken Subject: [PATCH v3 for-next 3/3] io_uring: support multishot in recvmsg Date: Thu, 14 Jul 2022 04:02:58 -0700 Message-ID: <20220714110258.1336200-4-dylany@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220714110258.1336200-1-dylany@fb.com> References: <20220714110258.1336200-1-dylany@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-ORIG-GUID: -AIyXMuGCVvbMYI_szcU2VeCput3-NWb X-Proofpoint-GUID: -AIyXMuGCVvbMYI_szcU2VeCput3-NWb X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.883,Hydra:6.0.517,FMLib:17.11.122.1 definitions=2022-07-14_08,2022-07-14_01,2022-06-22_01 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Similar to multishot recv, this will require provided buffers to be used. However recvmsg is much more complex than recv as it has multiple outputs. Specifically flags, name, and control messages. Support this by introducing a new struct io_uring_recvmsg_out with 4 fields. namelen, controllen and flags match the similar out fields in msghdr from standard recvmsg(2), payloadlen is the length of the payload following the header. This struct is placed at the start of the returned buffer. Based on what the user specifies in struct msghdr, the next bytes of the buffer will be name (the next msg_namelen bytes), and then control (the next msg_controllen bytes). The payload will come at the end. The return value in the CQE is the total used size of the provided buffer. Signed-off-by: Dylan Yudaken --- include/uapi/linux/io_uring.h | 7 ++ io_uring/net.c | 182 ++++++++++++++++++++++++++++++---- io_uring/net.h | 6 ++ 3 files changed, 176 insertions(+), 19 deletions(-) diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 499679134961..4c9b11e2e991 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -613,4 +613,11 @@ struct io_uring_file_index_range { __u64 resv; }; +struct io_uring_recvmsg_out { + __u32 namelen; + __u32 controllen; + __u32 payloadlen; + __u32 flags; +}; + #endif diff --git a/io_uring/net.c b/io_uring/net.c index 5bc3440a8290..7a4707cbf863 100644 --- a/io_uring/net.c +++ b/io_uring/net.c @@ -325,6 +325,21 @@ int io_send(struct io_kiocb *req, unsigned int issue_flags) return IOU_OK; } +static int io_recvmsg_multishot_overflow(struct io_async_msghdr *iomsg) +{ + unsigned long hdr; + + if (check_add_overflow(sizeof(struct io_uring_recvmsg_out), + (unsigned long)iomsg->namelen, &hdr)) + return -EOVERFLOW; + if (check_add_overflow(hdr, iomsg->controllen, &hdr)) + return -EOVERFLOW; + if (hdr > INT_MAX) + return -EOVERFLOW; + + return 0; +} + static int __io_recvmsg_copy_hdr(struct io_kiocb *req, struct io_async_msghdr *iomsg) { @@ -352,6 +367,13 @@ static int __io_recvmsg_copy_hdr(struct io_kiocb *req, sr->len = iomsg->fast_iov[0].iov_len; iomsg->free_iov = NULL; } + + if (req->flags & REQ_F_APOLL_MULTISHOT) { + iomsg->namelen = msg.msg_namelen; + iomsg->controllen = msg.msg_controllen; + if (io_recvmsg_multishot_overflow(iomsg)) + return -EOVERFLOW; + } } else { iomsg->free_iov = iomsg->fast_iov; ret = __import_iovec(READ, msg.msg_iov, msg.msg_iovlen, UIO_FASTIOV, @@ -399,6 +421,13 @@ static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req, sr->len = clen; iomsg->free_iov = NULL; } + + if (req->flags & REQ_F_APOLL_MULTISHOT) { + iomsg->namelen = msg.msg_namelen; + iomsg->controllen = msg.msg_controllen; + if (io_recvmsg_multishot_overflow(iomsg)) + return -EOVERFLOW; + } } else { iomsg->free_iov = iomsg->fast_iov; ret = __import_iovec(READ, (struct iovec __user *)uiov, msg.msg_iovlen, @@ -455,8 +484,6 @@ 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) @@ -483,12 +510,13 @@ static inline void io_recv_prep_retry(struct io_kiocb *req) } /* - * Finishes io_recv + * Finishes io_recv and io_recvmsg. * * Returns true if it is actually finished, or false if it should run * again (for multishot). */ -static inline bool io_recv_finish(struct io_kiocb *req, int *ret, unsigned int cflags) +static inline bool io_recv_finish(struct io_kiocb *req, int *ret, + unsigned int cflags, bool mshot_finished) { if (!(req->flags & REQ_F_APOLL_MULTISHOT)) { io_req_set_res(req, *ret, cflags); @@ -496,7 +524,7 @@ static inline bool io_recv_finish(struct io_kiocb *req, int *ret, unsigned int c return true; } - if (*ret > 0) { + if (!mshot_finished) { if (io_post_aux_cqe(req->ctx, req->cqe.user_data, *ret, cflags | IORING_CQE_F_MORE, false)) { io_recv_prep_retry(req); @@ -518,6 +546,91 @@ static inline bool io_recv_finish(struct io_kiocb *req, int *ret, unsigned int c return true; } +static int io_recvmsg_prep_multishot(struct io_async_msghdr *kmsg, struct io_sr_msg *sr, + void __user **buf, size_t *len) +{ + unsigned long ubuf = (unsigned long)*buf; + unsigned long hdr; + + hdr = sizeof(struct io_uring_recvmsg_out) + kmsg->namelen + kmsg->controllen; + if (*len < hdr) + return -EFAULT; + + if (kmsg->controllen) { + unsigned long control = ubuf + hdr - kmsg->controllen; + + kmsg->msg.msg_control_user = (void *)control; + kmsg->msg.msg_controllen = kmsg->controllen; + } + + sr->buf = *buf; /* stash for later copy */ + *buf = (void *)(ubuf + hdr); + kmsg->payloadlen = *len = *len - hdr; + return 0; +} + +struct io_recvmsg_multishot_hdr { + struct io_uring_recvmsg_out msg; + struct sockaddr_storage addr; +}; + +static int io_recvmsg_multishot( + struct socket *sock, + struct io_sr_msg *io, + struct io_async_msghdr *kmsg, + unsigned int flags, + bool *finished) +{ + int err; + int copy_len; + struct io_recvmsg_multishot_hdr hdr; + + if (kmsg->namelen) + kmsg->msg.msg_name = &hdr.addr; + kmsg->msg.msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT); + kmsg->msg.msg_namelen = 0; + + if (sock->file->f_flags & O_NONBLOCK) + flags |= MSG_DONTWAIT; + + err = sock_recvmsg(sock, &kmsg->msg, flags); + *finished = err <= 0; + if (err < 0) + return err; + + hdr.msg = (struct io_uring_recvmsg_out) { + .controllen = kmsg->controllen - kmsg->msg.msg_controllen, + .flags = kmsg->msg.msg_flags & ~MSG_CMSG_COMPAT + }; + + hdr.msg.payloadlen = err; + if (err > kmsg->payloadlen) + err = kmsg->payloadlen; + + copy_len = sizeof(struct io_uring_recvmsg_out); + if (kmsg->msg.msg_namelen > kmsg->namelen) + copy_len += kmsg->namelen; + else + copy_len += kmsg->msg.msg_namelen; + + /* + * "fromlen shall refer to the value before truncation.." + * 1003.1g + */ + hdr.msg.namelen = kmsg->msg.msg_namelen; + + /* ensure that there is no gap between hdr and sockaddr_storage */ + BUILD_BUG_ON(offsetof(struct io_recvmsg_multishot_hdr, addr) != + sizeof(struct io_uring_recvmsg_out)); + if (copy_to_user(io->buf, &hdr, copy_len)) { + *finished = true; + return -EFAULT; + } + + return sizeof(struct io_uring_recvmsg_out) + kmsg->namelen + + kmsg->controllen + err; +} + int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) { struct io_sr_msg *sr = io_kiocb_to_cmd(req); @@ -527,6 +640,7 @@ 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; + bool mshot_finished = true; sock = sock_from_file(req->file); if (unlikely(!sock)) @@ -545,16 +659,29 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) (sr->flags & IORING_RECVSEND_POLL_FIRST)) return io_setup_async_msg(req, kmsg, issue_flags); +retry_multishot: if (io_do_buffer_select(req)) { void __user *buf; + size_t len = sr->len; - buf = io_buffer_select(req, &sr->len, issue_flags); + buf = io_buffer_select(req, &len, issue_flags); if (!buf) return -ENOBUFS; + + if (req->flags & REQ_F_APOLL_MULTISHOT) { + ret = io_recvmsg_prep_multishot(kmsg, sr, + &buf, &len); + + if (ret) { + io_kbuf_recycle(req, issue_flags); + return ret; + } + } + kmsg->fast_iov[0].iov_base = buf; - kmsg->fast_iov[0].iov_len = sr->len; + kmsg->fast_iov[0].iov_len = len; iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov, 1, - sr->len); + len); } flags = sr->msg_flags; @@ -564,10 +691,22 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) min_ret = iov_iter_count(&kmsg->msg.msg_iter); kmsg->msg.msg_get_inq = 1; - ret = __sys_recvmsg_sock(sock, &kmsg->msg, sr->umsg, kmsg->uaddr, flags); + if (req->flags & REQ_F_APOLL_MULTISHOT) + ret = io_recvmsg_multishot(sock, sr, kmsg, flags, + &mshot_finished); + else + ret = __sys_recvmsg_sock(sock, &kmsg->msg, sr->umsg, kmsg->uaddr, flags); + if (ret < min_ret) { - if (ret == -EAGAIN && force_nonblock) - return io_setup_async_msg(req, kmsg, issue_flags); + if (ret == -EAGAIN && force_nonblock) { + ret = io_setup_async_msg(req, kmsg, issue_flags); + 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 == -ERESTARTSYS) ret = -EINTR; if (ret > 0 && io_net_retry(sock, flags)) { @@ -580,11 +719,6 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) req_set_fail(req); } - /* fast path, check for non-NULL to avoid function call */ - if (kmsg->free_iov) - kfree(kmsg->free_iov); - io_netmsg_recycle(req, issue_flags); - req->flags &= ~REQ_F_NEED_CLEANUP; if (ret > 0) ret += sr->done_io; else if (sr->done_io) @@ -596,8 +730,18 @@ int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) if (kmsg->msg.msg_inq) cflags |= IORING_CQE_F_SOCK_NONEMPTY; - io_req_set_res(req, ret, cflags); - return IOU_OK; + if (!io_recv_finish(req, &ret, cflags, mshot_finished)) + goto retry_multishot; + + if (mshot_finished) { + io_netmsg_recycle(req, issue_flags); + /* fast path, check for non-NULL to avoid function call */ + if (kmsg->free_iov) + kfree(kmsg->free_iov); + req->flags &= ~REQ_F_NEED_CLEANUP; + } + + return ret; } int io_recv(struct io_kiocb *req, unsigned int issue_flags) @@ -684,7 +828,7 @@ int io_recv(struct io_kiocb *req, unsigned int issue_flags) if (msg.msg_inq) cflags |= IORING_CQE_F_SOCK_NONEMPTY; - if (!io_recv_finish(req, &ret, cflags)) + if (!io_recv_finish(req, &ret, cflags, ret <= 0)) goto retry_multishot; return ret; diff --git a/io_uring/net.h b/io_uring/net.h index 178a6d8b76e0..db20ce9d6546 100644 --- a/io_uring/net.h +++ b/io_uring/net.h @@ -9,6 +9,12 @@ struct io_async_msghdr { union { struct iovec fast_iov[UIO_FASTIOV]; + struct { + struct iovec fast_iov_one; + __kernel_size_t controllen; + int namelen; + __kernel_size_t payloadlen; + }; struct io_cache_entry cache; }; /* points to an allocated iov, if NULL we use fast_iov instead */