From patchwork Mon Jan 16 23:10:03 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 643365 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 C5B5AC678D4 for ; Mon, 16 Jan 2023 23:14:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235246AbjAPXOP (ORCPT ); Mon, 16 Jan 2023 18:14:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48820 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235418AbjAPXNh (ORCPT ); Mon, 16 Jan 2023 18:13:37 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B1EF32ED75 for ; Mon, 16 Jan 2023 15:10:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1673910611; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EU0pOV6WBLH3AThSCCtWqw1z4qNF39IxpGe04ts73SI=; b=KMOzHRIJJUWXBlyRWBI/M6tafkITKUDRyjvzdXGhznL4aBIYbHRP/+WCdb4MA9aTTbHWHZ y870npR6fRffOMvDSkMlXyJoGzcAWt+LULKM/5GvfFBbFg/8GCXuuVFlOCgNI46H1jSj+L gRGm52/wLSvCgTqwuCVjUZuOJGKdn74= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-185-RByxuKzUOKioXzZbR3mJUw-1; Mon, 16 Jan 2023 18:10:06 -0500 X-MC-Unique: RByxuKzUOKioXzZbR3mJUw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 0ACC71C0432B; Mon, 16 Jan 2023 23:10:06 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.23]) by smtp.corp.redhat.com (Postfix) with ESMTP id 57C3C1121319; Mon, 16 Jan 2023 23:10:04 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH v6 17/34] scsi: [RFC] Use netfs_extract_iter_to_sg() From: David Howells To: Al Viro Cc: "James E.J. Bottomley" , "Martin K. Petersen" , Christoph Hellwig , linux-scsi@vger.kernel.org, dhowells@redhat.com, Christoph Hellwig , Matthew Wilcox , Jens Axboe , Jan Kara , Jeff Layton , Logan Gunthorpe , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Date: Mon, 16 Jan 2023 23:10:03 +0000 Message-ID: <167391060380.2311931.5962669831677025433.stgit@warthog.procyon.org.uk> In-Reply-To: <167391047703.2311931.8115712773222260073.stgit@warthog.procyon.org.uk> References: <167391047703.2311931.8115712773222260073.stgit@warthog.procyon.org.uk> User-Agent: StGit/1.5 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Use netfs_extract_iter_to_sg() to build a scatterlist from an iterator. Note that if this fits, netfs_extract_iter_to_sg() should move to core code. Signed-off-by: David Howells cc: James E.J. Bottomley cc: Martin K. Petersen cc: Christoph Hellwig cc: linux-scsi@vger.kernel.org --- drivers/vhost/scsi.c | 78 +++++++++++++++----------------------------------- 1 file changed, 23 insertions(+), 55 deletions(-) diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index 5d10837d19ec..af897cc4036d 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -34,6 +34,7 @@ #include #include #include +#include #include "vhost.h" @@ -75,6 +76,9 @@ struct vhost_scsi_cmd { u32 tvc_prot_sgl_count; /* Saved unpacked SCSI LUN for vhost_scsi_target_queue_cmd() */ u32 tvc_lun; + /* Cleanup modes for scatterlists */ + unsigned int tvc_cleanup_mode; + unsigned int tvc_prot_cleanup_mode; /* Pointer to the SGL formatted memory from virtio-scsi */ struct scatterlist *tvc_sgl; struct scatterlist *tvc_prot_sgl; @@ -339,11 +343,13 @@ static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd) if (tv_cmd->tvc_sgl_count) { for (i = 0; i < tv_cmd->tvc_sgl_count; i++) - put_page(sg_page(&tv_cmd->tvc_sgl[i])); + page_put_unpin(sg_page(&tv_cmd->tvc_sgl[i]), + tv_cmd->tvc_cleanup_mode); } if (tv_cmd->tvc_prot_sgl_count) { for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++) - put_page(sg_page(&tv_cmd->tvc_prot_sgl[i])); + page_put_unpin(sg_page(&tv_cmd->tvc_prot_sgl[i]), + tv_cmd->tvc_prot_cleanup_mode); } sbitmap_clear_bit(&svq->scsi_tags, se_cmd->map_tag); @@ -631,41 +637,6 @@ vhost_scsi_get_cmd(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg, return cmd; } -/* - * Map a user memory range into a scatterlist - * - * Returns the number of scatterlist entries used or -errno on error. - */ -static int -vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd, - struct iov_iter *iter, - struct scatterlist *sgl, - bool write) -{ - struct page **pages = cmd->tvc_upages; - struct scatterlist *sg = sgl; - ssize_t bytes; - size_t offset; - unsigned int npages = 0, gup_flags = 0; - - gup_flags |= write ? FOLL_SOURCE_BUF : FOLL_DEST_BUF; - - bytes = iov_iter_get_pages(iter, pages, LONG_MAX, - VHOST_SCSI_PREALLOC_UPAGES, &offset, - gup_flags); - /* No pages were pinned */ - if (bytes <= 0) - return bytes < 0 ? bytes : -EFAULT; - - while (bytes) { - unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes); - sg_set_page(sg++, pages[npages++], n, offset); - bytes -= n; - offset = 0; - } - return npages; -} - static int vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls) { @@ -689,24 +660,19 @@ vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls) static int vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write, struct iov_iter *iter, - struct scatterlist *sg, int sg_count) + struct scatterlist *sg, int sg_count, + unsigned int *cleanup_mode) { - struct scatterlist *p = sg; - int ret; + struct sg_table sgt = { .sgl = sg }; + unsigned int gup_flags = write ? FOLL_SOURCE_BUF : FOLL_DEST_BUF; + ssize_t ret; - while (iov_iter_count(iter)) { - ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write); - if (ret < 0) { - while (p < sg) { - struct page *page = sg_page(p++); - if (page) - put_page(page); - } - return ret; - } - sg += ret; - } - return 0; + ret = netfs_extract_iter_to_sg(iter, LONG_MAX, &sgt, sg_count, gup_flags); + if (ret > 0) + sg_mark_end(sg + sgt.nents - 1); + + *cleanup_mode = iov_iter_extract_mode(iter, gup_flags); + return ret; } static int @@ -730,7 +696,8 @@ vhost_scsi_mapal(struct vhost_scsi_cmd *cmd, ret = vhost_scsi_iov_to_sgl(cmd, write, prot_iter, cmd->tvc_prot_sgl, - cmd->tvc_prot_sgl_count); + cmd->tvc_prot_sgl_count, + &cmd->tvc_prot_cleanup_mode); if (ret < 0) { cmd->tvc_prot_sgl_count = 0; return ret; @@ -747,7 +714,8 @@ vhost_scsi_mapal(struct vhost_scsi_cmd *cmd, cmd->tvc_sgl, cmd->tvc_sgl_count); ret = vhost_scsi_iov_to_sgl(cmd, write, data_iter, - cmd->tvc_sgl, cmd->tvc_sgl_count); + cmd->tvc_sgl, cmd->tvc_sgl_count, + &cmd->tvc_cleanup_mode); if (ret < 0) { cmd->tvc_sgl_count = 0; return ret;