From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 75E01C2BB3F for ; Mon, 7 Dec 2020 22:17:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 41820239A1 for ; Mon, 7 Dec 2020 22:17:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728068AbgLGWQ4 (ORCPT ); Mon, 7 Dec 2020 17:16:56 -0500 Received: from aserp2130.oracle.com ([141.146.126.79]:58764 "EHLO aserp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728066AbgLGWQv (ORCPT ); Mon, 7 Dec 2020 17:16:51 -0500 Received: from pps.filterd (aserp2130.oracle.com [127.0.0.1]) by aserp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 0B7M9L19111978; Mon, 7 Dec 2020 22:16:07 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : subject : date : message-id : in-reply-to : references; s=corp-2020-01-29; bh=KmWXBf4xbjTY1HG5RKz2pxr7ScJKxwA7yTiSBxDQ7hc=; b=YjnBycwvf1r/jPhQ2PJDALMYNmX6FQou+0UKq6xmVG467oKIKaDZwPptsdRNlQUR1yBm 6/tBHnZr2MnvLFykKTxSNTkuAwUXskNXrjyYSWhoI1HcpNNYPeGX3OnPrzkOLG+BAZtE Vrgvj9dBbp1xZ3kX/0HmyQwsJmz/sHXLs2rw6l8wCGksxbvogKkQb98H33HAJAp2yOBG boet4kiTaV1cT77sRwxIaYBy0hvLuqOPIfWQDcxBdXsKoZcMsHN25wSLFI6uj01w2zB9 r2QDVBeegcHWIeDpHJG1Im4HC40TvkBicaM6chVi9ZNRa01o82Hd371x3LDXqfA845pz /A== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by aserp2130.oracle.com with ESMTP id 357yqbr17b-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 07 Dec 2020 22:16:07 +0000 Received: from pps.filterd (userp3030.oracle.com [127.0.0.1]) by userp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 0B7M9fUC044350; Mon, 7 Dec 2020 22:16:06 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userp3030.oracle.com with ESMTP id 358m4ww8y3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 07 Dec 2020 22:16:06 +0000 Received: from abhmp0017.oracle.com (abhmp0017.oracle.com [141.146.116.23]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 0B7MG6cH006735; Mon, 7 Dec 2020 22:16:06 GMT Received: from ca-ldom147.us.oracle.com (/10.129.68.131) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 07 Dec 2020 14:16:06 -0800 From: Bijan Mottahedeh To: axboe@kernel.dk, asml.silence@gmail.com, io-uring@vger.kernel.org Subject: [PATCH v2 08/13] io_uring: implement fixed buffers registration similar to fixed files Date: Mon, 7 Dec 2020 14:15:47 -0800 Message-Id: <1607379352-68109-9-git-send-email-bijan.mottahedeh@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1607379352-68109-1-git-send-email-bijan.mottahedeh@oracle.com> References: <1607379352-68109-1-git-send-email-bijan.mottahedeh@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9828 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 spamscore=0 suspectscore=2 bulkscore=0 malwarescore=0 phishscore=0 adultscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2012070145 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9828 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=2 mlxlogscore=999 clxscore=1015 malwarescore=0 bulkscore=0 phishscore=0 adultscore=0 spamscore=0 priorityscore=1501 mlxscore=0 lowpriorityscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2012070145 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Apply fixed_rsrc functionality for fixed buffers support. Signed-off-by: Bijan Mottahedeh --- fs/io_uring.c | 240 +++++++++++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 204 insertions(+), 36 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 25b575e..a51d1e6 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -104,6 +104,14 @@ #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \ IORING_REGISTER_LAST + IORING_OP_LAST) +/* + * Shift of 7 is 128 entries, or exactly one page on 64-bit archs + */ +#define IORING_BUF_TABLE_SHIFT 7 /* struct io_mapped_ubuf */ +#define IORING_MAX_BUFS_TABLE (1U << IORING_BUF_TABLE_SHIFT) +#define IORING_BUF_TABLE_MASK (IORING_MAX_BUFS_TABLE - 1) +#define IORING_MAX_FIXED_BUFS UIO_MAXIOV + struct io_uring { u32 head ____cacheline_aligned_in_smp; u32 tail ____cacheline_aligned_in_smp; @@ -336,8 +344,8 @@ struct io_ring_ctx { unsigned nr_user_files; /* if used, fixed mapped user buffers */ + struct fixed_rsrc_data *buf_data; unsigned nr_user_bufs; - struct io_mapped_ubuf *user_bufs; struct user_struct *user; @@ -2962,6 +2970,15 @@ static void kiocb_done(struct kiocb *kiocb, ssize_t ret, io_rw_done(kiocb, ret); } +static inline struct io_mapped_ubuf *io_buf_from_index(struct io_ring_ctx *ctx, + int index) +{ + struct fixed_rsrc_table *table; + + table = &ctx->buf_data->table[index >> IORING_BUF_TABLE_SHIFT]; + return &table->bufs[index & IORING_BUF_TABLE_MASK]; +} + static ssize_t io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter) { @@ -2975,7 +2992,7 @@ static ssize_t io_import_fixed(struct io_kiocb *req, int rw, if (unlikely(buf_index >= ctx->nr_user_bufs)) return -EFAULT; index = array_index_nospec(buf_index, ctx->nr_user_bufs); - imu = &ctx->user_bufs[index]; + imu = io_buf_from_index(ctx, index); buf_addr = req->rw.addr; /* overflow */ @@ -8296,28 +8313,71 @@ static unsigned long ring_pages(unsigned sq_entries, unsigned cq_entries) return pages; } -static int io_sqe_buffers_unregister(struct io_ring_ctx *ctx) +static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf *imu) { - int i, j; + unsigned i; - if (!ctx->user_bufs) - return -ENXIO; + for (i = 0; i < imu->nr_bvecs; i++) + unpin_user_page(imu->bvec[i].bv_page); - for (i = 0; i < ctx->nr_user_bufs; i++) { - struct io_mapped_ubuf *imu = &ctx->user_bufs[i]; + if (imu->acct_pages) + io_unaccount_mem(ctx, imu->nr_bvecs, ACCT_PINNED); + kvfree(imu->bvec); + imu->nr_bvecs = 0; +} - for (j = 0; j < imu->nr_bvecs; j++) - unpin_user_page(imu->bvec[j].bv_page); +static void io_buffers_unmap(struct io_ring_ctx *ctx) +{ + unsigned i; + struct io_mapped_ubuf *imu; - if (imu->acct_pages) - io_unaccount_mem(ctx, imu->acct_pages, ACCT_PINNED); - kvfree(imu->bvec); - imu->nr_bvecs = 0; + for (i = 0; i < ctx->nr_user_bufs; i++) { + imu = io_buf_from_index(ctx, i); + io_buffer_unmap(ctx, imu); } +} + +static void io_buffers_map_free(struct io_ring_ctx *ctx) +{ + struct fixed_rsrc_data *data = ctx->buf_data; + unsigned nr_tables, i; + + if (!data) + return; - kfree(ctx->user_bufs); - ctx->user_bufs = NULL; + nr_tables = DIV_ROUND_UP(ctx->nr_user_bufs, IORING_MAX_BUFS_TABLE); + for (i = 0; i < nr_tables; i++) + kfree(data->table[i].bufs); + kfree(data->table); + percpu_ref_exit(&data->refs); + kfree(data); + ctx->buf_data = NULL; ctx->nr_user_bufs = 0; +} + +static int io_sqe_buffers_unregister(struct io_ring_ctx *ctx) +{ + struct fixed_rsrc_data *data = ctx->buf_data; + struct fixed_rsrc_ref_node *ref_node = NULL; + + if (!data) + return -ENXIO; + + io_rsrc_ref_lock(ctx); + ref_node = data->node; + io_rsrc_ref_unlock(ctx); + if (ref_node) + percpu_ref_kill(&ref_node->refs); + + percpu_ref_kill(&data->refs); + + /* wait for all refs nodes to complete */ + flush_delayed_work(&ctx->rsrc_put_work); + wait_for_completion(&data->done); + + io_buffers_unmap(ctx); + io_buffers_map_free(ctx); + return 0; } @@ -8370,7 +8430,13 @@ static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages, /* check previously registered pages */ for (i = 0; i < ctx->nr_user_bufs; i++) { - struct io_mapped_ubuf *imu = &ctx->user_bufs[i]; + struct fixed_rsrc_table *table; + struct io_mapped_ubuf *imu; + unsigned index; + + table = &ctx->buf_data->table[i >> IORING_BUF_TABLE_SHIFT]; + index = i & IORING_BUF_TABLE_MASK; + imu = &table->bufs[index]; for (j = 0; j < imu->nr_bvecs; j++) { if (!PageCompound(imu->bvec[j].bv_page)) @@ -8505,19 +8571,80 @@ static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, return ret; } -static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args) +static void io_free_buf_tables(struct fixed_rsrc_data *buf_data, + unsigned nr_tables) { - if (ctx->user_bufs) - return -EBUSY; - if (!nr_args || nr_args > UIO_MAXIOV) - return -EINVAL; + int i; - ctx->user_bufs = kcalloc(nr_args, sizeof(struct io_mapped_ubuf), - GFP_KERNEL); - if (!ctx->user_bufs) - return -ENOMEM; + for (i = 0; i < nr_tables; i++) { + struct fixed_rsrc_table *table = &buf_data->table[i]; + kfree(table->bufs); + } +} - return 0; +static int io_alloc_buf_tables(struct fixed_rsrc_data *buf_data, + unsigned nr_tables, unsigned nr_bufs) +{ + int i; + + for (i = 0; i < nr_tables; i++) { + struct fixed_rsrc_table *table = &buf_data->table[i]; + unsigned this_bufs; + + this_bufs = min(nr_bufs, IORING_MAX_BUFS_TABLE); + table->bufs = kcalloc(this_bufs, sizeof(struct io_mapped_ubuf), + GFP_KERNEL); + if (!table->bufs) + break; + nr_bufs -= this_bufs; + } + + if (i == nr_tables) + return 0; + + io_free_buf_tables(buf_data, nr_tables); + return 1; +} + +static struct fixed_rsrc_data *io_buffers_map_alloc(struct io_ring_ctx *ctx, + unsigned int nr_args) +{ + unsigned nr_tables; + struct fixed_rsrc_data *buf_data; + int ret = -ENOMEM; + + if (ctx->buf_data) + return ERR_PTR(-EBUSY); + if (!nr_args || nr_args > IORING_MAX_FIXED_BUFS) + return ERR_PTR(-EINVAL); + + buf_data = kzalloc(sizeof(*ctx->buf_data), GFP_KERNEL); + if (!buf_data) + return ERR_PTR(-ENOMEM); + buf_data->ctx = ctx; + init_completion(&buf_data->done); + + nr_tables = DIV_ROUND_UP(nr_args, IORING_MAX_BUFS_TABLE); + buf_data->table = kcalloc(nr_tables, sizeof(*buf_data->table), + GFP_KERNEL); + if (!buf_data->table) + goto out_free; + + if (percpu_ref_init(&buf_data->refs, io_rsrc_ref_kill, + PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) + goto out_free; + + if (io_alloc_buf_tables(buf_data, nr_tables, nr_args)) + goto out_ref; + + return buf_data; + +out_ref: + percpu_ref_exit(&buf_data->refs); +out_free: + kfree(buf_data->table); + kfree(buf_data); + return ERR_PTR(ret); } static int io_buffer_validate(struct iovec *iov) @@ -8537,39 +8664,79 @@ static int io_buffer_validate(struct iovec *iov) return 0; } +static void io_ring_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc) +{ + io_buffer_unmap(ctx, prsrc->buf); +} + +static struct fixed_rsrc_ref_node *alloc_fixed_buf_ref_node( + struct io_ring_ctx *ctx) +{ + struct fixed_rsrc_ref_node *ref_node; + + ref_node = alloc_fixed_rsrc_ref_node(ctx); + ref_node->rsrc_data = ctx->buf_data; + ref_node->rsrc_put = io_ring_buf_put; + return ref_node; +} + static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg, unsigned int nr_args) { int i, ret; struct iovec iov; struct page *last_hpage = NULL; + struct fixed_rsrc_ref_node *ref_node; + struct fixed_rsrc_data *buf_data; - ret = io_buffers_map_alloc(ctx, nr_args); - if (ret) - return ret; + buf_data = io_buffers_map_alloc(ctx, nr_args); + if (IS_ERR(buf_data)) + return PTR_ERR(buf_data); - for (i = 0; i < nr_args; i++) { - struct io_mapped_ubuf *imu = &ctx->user_bufs[i]; + for (i = 0; i < nr_args; i++, ctx->nr_user_bufs++) { + struct fixed_rsrc_table *table; + struct io_mapped_ubuf *imu; + unsigned index; ret = io_copy_iov(ctx, &iov, arg, i); if (ret) break; + /* allow sparse sets */ + if (!iov.iov_base && !iov.iov_len) + continue; + ret = io_buffer_validate(&iov); if (ret) break; + table = &buf_data->table[i >> IORING_BUF_TABLE_SHIFT]; + index = i & IORING_BUF_TABLE_MASK; + imu = &table->bufs[index]; + ret = io_sqe_buffer_register(ctx, &iov, imu, &last_hpage); if (ret) break; + } - ctx->nr_user_bufs++; + ctx->buf_data = buf_data; + if (ret) { + io_sqe_buffers_unregister(ctx); + return ret; } - if (ret) + ref_node = alloc_fixed_buf_ref_node(ctx); + if (IS_ERR(ref_node)) { io_sqe_buffers_unregister(ctx); + return PTR_ERR(ref_node); + } - return ret; + buf_data->node = ref_node; + io_rsrc_ref_lock(ctx); + list_add(&ref_node->node, &ctx->rsrc_ref_list); + io_rsrc_ref_unlock(ctx); + percpu_ref_get(&buf_data->refs); + return 0; } static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg) @@ -9348,7 +9515,7 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) } seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs); for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) { - struct io_mapped_ubuf *buf = &ctx->user_bufs[i]; + struct io_mapped_ubuf *buf = io_buf_from_index(ctx, i); seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, (unsigned int) buf->len); @@ -9851,6 +10018,7 @@ static bool io_register_op_must_quiesce(int op) switch (op) { case IORING_UNREGISTER_FILES: case IORING_REGISTER_FILES_UPDATE: + case IORING_UNREGISTER_BUFFERS: case IORING_REGISTER_PROBE: case IORING_REGISTER_PERSONALITY: case IORING_UNREGISTER_PERSONALITY: -- 1.8.3.1