From patchwork Mon May 30 13:15:20 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiaoguang Wang X-Patchwork-Id: 12864630 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 3FB2BC433EF for ; Mon, 30 May 2022 13:15:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232854AbiE3NP2 (ORCPT ); Mon, 30 May 2022 09:15:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41728 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236461AbiE3NPZ (ORCPT ); Mon, 30 May 2022 09:15:25 -0400 Received: from out30-42.freemail.mail.aliyun.com (out30-42.freemail.mail.aliyun.com [115.124.30.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 89F6F546BE for ; Mon, 30 May 2022 06:15:23 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R581e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01424;MF=xiaoguang.wang@linux.alibaba.com;NM=1;PH=DS;RN=3;SR=0;TI=SMTPD_---0VEqJIer_1653916520; Received: from localhost(mailfrom:xiaoguang.wang@linux.alibaba.com fp:SMTPD_---0VEqJIer_1653916520) by smtp.aliyun-inc.com(127.0.0.1); Mon, 30 May 2022 21:15:21 +0800 From: Xiaoguang Wang To: io-uring@vger.kernel.org Cc: axboe@kernel.dk, asml.silence@gmail.com Subject: [PATCH v2] io_uring: let IORING_OP_FILES_UPDATE support to choose fixed file slots Date: Mon, 30 May 2022 21:15:20 +0800 Message-Id: <20220530131520.47712-1-xiaoguang.wang@linux.alibaba.com> X-Mailer: git-send-email 2.14.4.44.g2045bb6 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org One big issue with file registration feature is that it needs user space apps to maintain free slot info about io_uring's fixed file table, which really is a burden for development. Now since io_uring starts to choose free file slot for user space apps by using IORING_FILE_INDEX_ALLOC flag in accept or open operations, but they need app to uses direct accept or direct open, which as far as I know, some apps are not prepared to use direct accept or open yet. To support apps, who still need real fds, use registration feature easier, let IORING_OP_FILES_UPDATE support to choose fixed file slots, which will store picked fixed files slots in fd array and let cqe return the number of slots allocated. Suggested-by: Hao Xu Signed-off-by: Xiaoguang Wang --- V2: Add illegal flags check in io_close_prep(). --- fs/io_uring.c | 75 +++++++++++++++++++++++++++++++++++++------ include/uapi/linux/io_uring.h | 1 + 2 files changed, 66 insertions(+), 10 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 6d91148e9679..18a7459fb6e7 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -574,6 +574,7 @@ struct io_close { struct file *file; int fd; u32 file_slot; + u32 flags; }; struct io_timeout_data { @@ -1366,7 +1367,9 @@ static int io_req_prep_async(struct io_kiocb *req); static int io_install_fixed_file(struct io_kiocb *req, struct file *file, unsigned int issue_flags, u32 slot_index); -static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags); +static int __io_close_fixed(struct io_kiocb *req, unsigned int issue_flags, + unsigned int offset); +static inline int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags); static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer); static void io_eventfd_signal(struct io_ring_ctx *ctx); @@ -5945,16 +5948,22 @@ static int io_statx(struct io_kiocb *req, unsigned int issue_flags) return 0; } +#define IORING_CLOSE_FD_AND_FILE_SLOT 1 + static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { - if (sqe->off || sqe->addr || sqe->len || sqe->rw_flags || sqe->buf_index) + if (sqe->off || sqe->addr || sqe->len || sqe->buf_index) return -EINVAL; if (req->flags & REQ_F_FIXED_FILE) return -EBADF; req->close.fd = READ_ONCE(sqe->fd); req->close.file_slot = READ_ONCE(sqe->file_index); - if (req->close.file_slot && req->close.fd) + req->close.flags = READ_ONCE(sqe->close_flags); + if (req->close.flags & ~IORING_CLOSE_FD_AND_FILE_SLOT) + return -EINVAL; + if (!(req->close.flags & IORING_CLOSE_FD_AND_FILE_SLOT) && + req->close.file_slot && req->close.fd) return -EINVAL; return 0; @@ -5970,7 +5979,8 @@ static int io_close(struct io_kiocb *req, unsigned int issue_flags) if (req->close.file_slot) { ret = io_close_fixed(req, issue_flags); - goto err; + if (ret || !(req->close.flags & IORING_CLOSE_FD_AND_FILE_SLOT)) + goto err; } spin_lock(&files->file_lock); @@ -8003,6 +8013,42 @@ static int io_files_update_prep(struct io_kiocb *req, return 0; } +static int io_files_update_with_index_alloc(struct io_kiocb *req, + unsigned int issue_flags) +{ + __s32 __user *fds = u64_to_user_ptr(req->rsrc_update.arg); + struct file *file; + unsigned int done, nr_fds = req->rsrc_update.nr_args; + int ret, fd; + + for (done = 0; done < nr_fds; done++) { + if (copy_from_user(&fd, &fds[done], sizeof(fd))) { + ret = -EFAULT; + break; + } + + file = fget(fd); + if (!file) { + ret = -EBADF; + goto out; + } + ret = io_fixed_fd_install(req, issue_flags, file, + IORING_FILE_INDEX_ALLOC); + if (ret < 0) + goto out; + if (copy_to_user(&fds[done], &ret, sizeof(ret))) { + ret = -EFAULT; + __io_close_fixed(req, issue_flags, ret); + break; + } + } + +out: + if (done) + return done; + return ret; +} + static int io_files_update(struct io_kiocb *req, unsigned int issue_flags) { struct io_ring_ctx *ctx = req->ctx; @@ -8016,10 +8062,14 @@ static int io_files_update(struct io_kiocb *req, unsigned int issue_flags) up.resv = 0; up.resv2 = 0; - io_ring_submit_lock(ctx, issue_flags); - ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE, - &up, req->rsrc_update.nr_args); - io_ring_submit_unlock(ctx, issue_flags); + if (req->rsrc_update.offset == IORING_FILE_INDEX_ALLOC) { + ret = io_files_update_with_index_alloc(req, issue_flags); + } else { + io_ring_submit_lock(ctx, issue_flags); + ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE, + &up, req->rsrc_update.nr_args); + io_ring_submit_unlock(ctx, issue_flags); + } if (ret < 0) req_set_fail(req); @@ -10183,9 +10233,9 @@ static int io_install_fixed_file(struct io_kiocb *req, struct file *file, return ret; } -static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags) +static int __io_close_fixed(struct io_kiocb *req, unsigned int issue_flags, + unsigned int offset) { - unsigned int offset = req->close.file_slot - 1; struct io_ring_ctx *ctx = req->ctx; struct io_fixed_file *file_slot; struct file *file; @@ -10222,6 +10272,11 @@ static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags) return ret; } +static inline int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags) +{ + return __io_close_fixed(req, issue_flags, req->close.file_slot - 1); +} + static int __io_sqe_files_update(struct io_ring_ctx *ctx, struct io_uring_rsrc_update2 *up, unsigned nr_args) diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 53e7dae92e42..e347b3fea4e4 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -47,6 +47,7 @@ struct io_uring_sqe { __u32 unlink_flags; __u32 hardlink_flags; __u32 xattr_flags; + __u32 close_flags; }; __u64 user_data; /* data to be passed back at completion time */ /* pack this to avoid bogus arm OABI complaints */