From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3EB031DE2CF for ; Mon, 28 Apr 2025 09:45:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745833509; cv=none; b=JsJUe2xxo1KsRogvAD4fgibWV3DnxLk8s1pP1d5OeGs8dtNaGlaClz3Tl/tEM9/xbzKDqR0ZqUG8o19Kaieui0+lYUKbR6mskQsTVkC+fc6Eq3ZEMu4ZYFnK93wJ8vVm2tcNsKsAuHpVbhsk8YaJmvtaWPwPEgQ9Z3SwoQ4JGEQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745833509; c=relaxed/simple; bh=5uhiwmaxLOgiH+d8sZ/RF95Ard1whrgHfzg2IOHGXjg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=B4wYFfXdLAQ6NHXRwWfqi1USepBIb4GTA8MB4CnfDkpmCbQz5GbjC3mQFF7zVE6V4icQMJmIS8tEMakWLktZJIqgeOQNH/Ex5X5JbxGamQOUb4mXWsdDEcWaNBQS5qCcDsP6796S2OkdBvX8fV6q7fOnYYNzhm5asPaElkpv1o4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=JnAxc210; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="JnAxc210" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1745833506; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=PwfsdcmBrLSt5UA63GogTrnK+Vei3hZmdQP3DOa+zgU=; b=JnAxc210SlqrzzgzysswE6ZTA3m6sjJh1IMfEb90Kwm3eFetKDy6oVJrR+Ab2Ktp5d4Yhg WrFXULFIsKhoit3cqcBkmCfzNRtURNZRVJVh+6aGli7zWMDn8fh83PpMZw9S7scg5GG/b+ qw/6KXdobj+0mc4MFWNJRJNJJHpGMts= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-547-zG74Cy3hNP-KgqgNGpdYHw-1; Mon, 28 Apr 2025 05:45:00 -0400 X-MC-Unique: zG74Cy3hNP-KgqgNGpdYHw-1 X-Mimecast-MFC-AGG-ID: zG74Cy3hNP-KgqgNGpdYHw_1745833499 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id A71BB19560AF; Mon, 28 Apr 2025 09:44:58 +0000 (UTC) Received: from localhost (unknown [10.72.116.134]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 8AC9E1800352; Mon, 28 Apr 2025 09:44:57 +0000 (UTC) From: Ming Lei To: Jens Axboe , io-uring@vger.kernel.org, Pavel Begunkov , linux-block@vger.kernel.org Cc: Uday Shankar , Caleb Sander Mateos , Keith Busch , Ming Lei Subject: [RFC PATCH 6/7] ublk: register buffer to specified io_uring & buf index via UBLK_F_AUTO_BUF_REG Date: Mon, 28 Apr 2025 17:44:17 +0800 Message-ID: <20250428094420.1584420-7-ming.lei@redhat.com> In-Reply-To: <20250428094420.1584420-1-ming.lei@redhat.com> References: <20250428094420.1584420-1-ming.lei@redhat.com> Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 Add UBLK_F_AUTO_BUF_REG for supporting to register buffer automatically to specified io_uring context and buffer index. Signed-off-by: Ming Lei --- drivers/block/ublk_drv.c | 56 ++++++++++++++++++++++++++++------- include/uapi/linux/ublk_cmd.h | 38 ++++++++++++++++++++++++ 2 files changed, 84 insertions(+), 10 deletions(-) diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index 1fd20e481a60..e82618442749 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -66,7 +66,8 @@ | UBLK_F_USER_COPY \ | UBLK_F_ZONED \ | UBLK_F_USER_RECOVERY_FAIL_IO \ - | UBLK_F_UPDATE_SIZE) + | UBLK_F_UPDATE_SIZE \ + | UBLK_F_AUTO_BUF_REG) #define UBLK_F_ALL_RECOVERY_FLAGS (UBLK_F_USER_RECOVERY \ | UBLK_F_USER_RECOVERY_REISSUE \ @@ -146,7 +147,10 @@ struct ublk_uring_cmd_pdu { struct ublk_io { /* userspace buffer address from io cmd */ - __u64 addr; + union { + __u64 addr; + struct ublk_auto_buf_reg buf; + }; unsigned int flags; int res; @@ -626,7 +630,7 @@ static inline bool ublk_support_zero_copy(const struct ublk_queue *ubq) static inline bool ublk_support_auto_buf_reg(const struct ublk_queue *ubq) { - return false; + return ubq->flags & UBLK_F_AUTO_BUF_REG; } static inline bool ublk_support_user_copy(const struct ublk_queue *ubq) @@ -1177,6 +1181,16 @@ static inline void __ublk_abort_rq(struct ublk_queue *ubq, blk_mq_end_request(rq, BLK_STS_IOERR); } + +static inline void ublk_init_auto_buf_reg(const struct ublk_io *io, + struct io_buf_data *data) +{ + data->index = io->buf.index; + data->ring_fd = io->buf.ring_fd; + data->has_fd = true; + data->registered_fd = io->buf.flags & UBLK_AUTO_BUF_REGISTERED_RING; +} + static bool ublk_auto_buf_reg(struct ublk_queue *ubq, struct request *req, struct ublk_io *io, unsigned int issue_flags) { @@ -1187,6 +1201,9 @@ static bool ublk_auto_buf_reg(struct ublk_queue *ubq, struct request *req, }; int ret; + if (ublk_support_auto_buf_reg(ubq)) + ublk_init_auto_buf_reg(io, &data); + /* one extra reference is dropped by ublk_io_release */ ublk_init_req_ref(ubq, req, 2); ret = io_buffer_register_bvec(io->cmd, &data, issue_flags); @@ -2045,7 +2062,7 @@ static int ublk_fetch(struct io_uring_cmd *cmd, struct ublk_queue *ubq, */ if (!buf_addr && !ublk_need_get_data(ubq)) goto out; - } else if (buf_addr) { + } else if (buf_addr && !ublk_support_auto_buf_reg(ubq)) { /* User copy requires addr to be unset */ ret = -EINVAL; goto out; @@ -2058,13 +2075,17 @@ static int ublk_fetch(struct io_uring_cmd *cmd, struct ublk_queue *ubq, return ret; } -static void ublk_auto_buf_unreg(struct ublk_io *io, struct io_uring_cmd *cmd, +static void ublk_auto_buf_unreg(const struct ublk_queue *ubq, + struct ublk_io *io, struct io_uring_cmd *cmd, struct request *req, unsigned int issue_flags) { struct io_buf_data data = { .index = req->tag, }; + if (ublk_support_auto_buf_reg(ubq)) + ublk_init_auto_buf_reg(io, &data); + WARN_ON_ONCE(io_buffer_unregister_bvec(cmd, &data, issue_flags)); io->flags &= ~UBLK_IO_FLAG_AUTO_BUF_REG; } @@ -2088,7 +2109,8 @@ static int ublk_commit_and_fetch(const struct ublk_queue *ubq, if (!ub_cmd->addr && (!ublk_need_get_data(ubq) || req_op(req) == REQ_OP_READ)) return -EINVAL; - } else if (req_op(req) != REQ_OP_ZONE_APPEND && ub_cmd->addr) { + } else if ((req_op(req) != REQ_OP_ZONE_APPEND && + !ublk_support_auto_buf_reg(ubq)) && ub_cmd->addr) { /* * User copy requires addr to be unset when command is * not zone append @@ -2097,7 +2119,7 @@ static int ublk_commit_and_fetch(const struct ublk_queue *ubq, } if (io->flags & UBLK_IO_FLAG_AUTO_BUF_REG) - ublk_auto_buf_unreg(io, cmd, req, issue_flags); + ublk_auto_buf_unreg(ubq, io, cmd, req, issue_flags); ublk_fill_io_cmd(io, cmd, ub_cmd->addr); @@ -2788,6 +2810,11 @@ static int ublk_ctrl_add_dev(const struct ublksrv_ctrl_cmd *header) else if (!(info.flags & UBLK_F_UNPRIVILEGED_DEV)) return -EPERM; + /* F_AUTO_BUF_REG and F_SUPPORT_ZERO_COPY can't co-exist */ + if ((info.flags & UBLK_F_AUTO_BUF_REG) && + (info.flags & UBLK_F_SUPPORT_ZERO_COPY)) + return -EINVAL; + /* forbid nonsense combinations of recovery flags */ switch (info.flags & UBLK_F_ALL_RECOVERY_FLAGS) { case 0: @@ -2817,8 +2844,11 @@ static int ublk_ctrl_add_dev(const struct ublksrv_ctrl_cmd *header) * For USER_COPY, we depends on userspace to fill request * buffer by pwrite() to ublk char device, which can't be * used for unprivileged device + * + * Same with zero copy or auto buffer register. */ - if (info.flags & (UBLK_F_USER_COPY | UBLK_F_SUPPORT_ZERO_COPY)) + if (info.flags & (UBLK_F_USER_COPY | UBLK_F_SUPPORT_ZERO_COPY | + UBLK_F_AUTO_BUF_REG)) return -EINVAL; } @@ -2876,17 +2906,22 @@ static int ublk_ctrl_add_dev(const struct ublksrv_ctrl_cmd *header) UBLK_F_URING_CMD_COMP_IN_TASK; /* GET_DATA isn't needed any more with USER_COPY or ZERO COPY */ - if (ub->dev_info.flags & (UBLK_F_USER_COPY | UBLK_F_SUPPORT_ZERO_COPY)) + if (ub->dev_info.flags & (UBLK_F_USER_COPY | UBLK_F_SUPPORT_ZERO_COPY | + UBLK_F_AUTO_BUF_REG)) ub->dev_info.flags &= ~UBLK_F_NEED_GET_DATA; /* * Zoned storage support requires reuse `ublksrv_io_cmd->addr` for * returning write_append_lba, which is only allowed in case of * user copy or zero copy + * + * UBLK_F_AUTO_BUF_REG can't be enabled for zoned because it need + * the space for getting ring_fd and buffer index. */ if (ublk_dev_is_zoned(ub) && (!IS_ENABLED(CONFIG_BLK_DEV_ZONED) || !(ub->dev_info.flags & - (UBLK_F_USER_COPY | UBLK_F_SUPPORT_ZERO_COPY)))) { + (UBLK_F_USER_COPY | UBLK_F_SUPPORT_ZERO_COPY)) || + (ub->dev_info.flags & UBLK_F_AUTO_BUF_REG))) { ret = -EINVAL; goto out_free_dev_number; } @@ -3403,6 +3438,7 @@ static int __init ublk_init(void) BUILD_BUG_ON((u64)UBLKSRV_IO_BUF_OFFSET + UBLKSRV_IO_BUF_TOTAL_SIZE < UBLKSRV_IO_BUF_OFFSET); + BUILD_BUG_ON(sizeof(struct ublk_auto_buf_reg) != sizeof(__u64)); init_waitqueue_head(&ublk_idr_wq); diff --git a/include/uapi/linux/ublk_cmd.h b/include/uapi/linux/ublk_cmd.h index be5c6c6b16e0..3d7c8c69cf06 100644 --- a/include/uapi/linux/ublk_cmd.h +++ b/include/uapi/linux/ublk_cmd.h @@ -219,6 +219,30 @@ */ #define UBLK_F_UPDATE_SIZE (1ULL << 10) +/* + * request buffer is registered automatically to ublk server specified + * io_uring context before delivering this io command to ublk server, + * meantime it is un-registered automatically when completing this io + * command. + * + * For using this feature: + * + * - ublk server has to create sparse buffer table + * + * - pass io_ring context FD from `ublksrv_io_cmd.buf.ring_fd`, and the FD + * can be registered io_ring FD if `UBLK_AUTO_BUF_REGISTERED_RING` is set + * in `ublksrv_io_cmd.flags`, or plain FD + * + * - pass buffer index from `ublksrv_io_cmd.buf.index` + * + * This way avoids extra cost from two uring_cmd, but also simplifies backend + * implementation, such as, the dependency on IO_REGISTER_IO_BUF and + * IO_UNREGISTER_IO_BUF becomes not necessary. + * + * This feature isn't available for UBLK_F_ZONED + */ +#define UBLK_F_AUTO_BUF_REG (1ULL << 11) + /* device state */ #define UBLK_S_DEV_DEAD 0 #define UBLK_S_DEV_LIVE 1 @@ -339,6 +363,14 @@ static inline __u32 ublksrv_get_flags(const struct ublksrv_io_desc *iod) return iod->op_flags >> 8; } +struct ublk_auto_buf_reg { + __s32 ring_fd; + __u16 index; +#define UBLK_AUTO_BUF_REGISTERED_RING (1 << 0) + __u8 flags; + __u8 _pad; +}; + /* issued to ublk driver via /dev/ublkcN */ struct ublksrv_io_cmd { __u16 q_id; @@ -363,6 +395,12 @@ struct ublksrv_io_cmd { */ __u64 addr; __u64 zone_append_lba; + + /* + * for AUTO_BUF_REG feature, F_ZONED can't be supported, + * and ->addr isn't used for zero copy + */ + struct ublk_auto_buf_reg auto_buf; }; }; -- 2.47.0