From nobody Tue Feb 10 00:00:58 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1576171480; cv=none; d=zohomail.com; s=zohoarc; b=d8PtMzspps2KbfAbbYR5ajeqzYcyw2S7nKH5F5mDWczOPB/NNMqbaOMH45+W9ww4ArAVQ0lk72feM98+Y2kDVKGE8ov9R8uW8Ai49jTbYZJiGu7fAe9z8M6QYqO/pTfo23NFaIXjaRa0oEVgkBqL63ChLr+PXbkeV9HXY5JnIBI= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1576171480; h=Content-Type:Content-Transfer-Encoding:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=dVCU0QAEMpRAgyvXWsnEyJwCGjSbQAWBP1xMWm8k5kI=; b=kRQWbl8+9BOQoojEG6m+fkKQc8Xcf8T8gLolaWCwICzAQbv+ErTQtxmGnfMf1B9IddznnLvD0SbLGc2OlE946xWeZs9uJLwh6JDa6EDur19d88cFzy4ResQsRNfPNK/AbkYIYWq1wSGmX3uS4166L5zAO8bNef9+w+btI14c5MU= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1576171480698523.4433791290545; Thu, 12 Dec 2019 09:24:40 -0800 (PST) Received: from localhost ([::1]:34621 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ifSCd-0006It-EE for importer@patchew.org; Thu, 12 Dec 2019 12:24:39 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:50357) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ifRVh-0005rd-Q1 for qemu-devel@nongnu.org; Thu, 12 Dec 2019 11:40:19 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ifRVg-0002FP-AH for qemu-devel@nongnu.org; Thu, 12 Dec 2019 11:40:17 -0500 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:50836 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ifRVg-0002Eh-2i for qemu-devel@nongnu.org; Thu, 12 Dec 2019 11:40:16 -0500 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-220-nVziACeQP8udgFneCGcNew-1; Thu, 12 Dec 2019 11:40:14 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4E1DD107ACC4 for ; Thu, 12 Dec 2019 16:40:13 +0000 (UTC) Received: from dgilbert-t580.localhost (ovpn-116-226.ams2.redhat.com [10.36.116.226]) by smtp.corp.redhat.com (Postfix) with ESMTP id 72C1A60BE1; Thu, 12 Dec 2019 16:40:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1576168815; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=dVCU0QAEMpRAgyvXWsnEyJwCGjSbQAWBP1xMWm8k5kI=; b=BS4WBlCNZuyqfBq4gU+XszBTO2oNoeELMivFeI7S+ITTAJZdf00YcFnb+U6zaLr49+K0/I 1BZU04LPPXmzXyeNcrZCWstxmsqUzb5470LHpKiDXQZszSIzFNj7c8SoZyJAQlpQDA5oxS ExRrxbAnfE8VNX8hmd7kGKO3djIAyvs= From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, stefanha@redhat.com, vgoyal@redhat.com Subject: [PATCH 040/104] virtiofsd: Pass write iov's all the way through Date: Thu, 12 Dec 2019 16:38:00 +0000 Message-Id: <20191212163904.159893-41-dgilbert@redhat.com> In-Reply-To: <20191212163904.159893-1-dgilbert@redhat.com> References: <20191212163904.159893-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-MC-Unique: nVziACeQP8udgFneCGcNew-1 X-Mimecast-Spam-Score: 0 Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 205.139.110.61 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: pass (identity @redhat.com) Content-Type: text/plain; charset="utf-8" From: "Dr. David Alan Gilbert" Pass the write iov pointing to guest RAM all the way through rather than copying the data. Signed-off-by: Dr. David Alan Gilbert --- tools/virtiofsd/fuse_virtio.c | 79 ++++++++++++++++++++++++++++++++--- 1 file changed, 73 insertions(+), 6 deletions(-) diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c index 99c877ea2e..3c778b6296 100644 --- a/tools/virtiofsd/fuse_virtio.c +++ b/tools/virtiofsd/fuse_virtio.c @@ -452,6 +452,10 @@ static void *fv_queue_thread(void *opaque) __func__, qi->qidx, (size_t)evalue, in_bytes, out_bytes); =20 while (1) { + bool allocated_bufv =3D false; + struct fuse_bufvec bufv; + struct fuse_bufvec *pbufv; + /* * An element contains one request and the space to send our * response They're spread over multiple descriptors in a @@ -493,14 +497,76 @@ static void *fv_queue_thread(void *opaque) __func__, elem->index); assert(0); /* TODO */ } - copy_from_iov(&fbuf, out_num, out_sg); - fbuf.size =3D out_len; + /* Copy just the first element and look at it */ + copy_from_iov(&fbuf, 1, out_sg); + + if (out_num > 2 && + out_sg[0].iov_len =3D=3D sizeof(struct fuse_in_header) && + ((struct fuse_in_header *)fbuf.mem)->opcode =3D=3D FUSE_WR= ITE && + out_sg[1].iov_len =3D=3D sizeof(struct fuse_write_in)) { + /* + * For a write we don't actually need to copy the + * data, we can just do it straight out of guest memory + * but we must still copy the headers in case the guest + * was nasty and changed them while we were using them. + */ + fuse_log(FUSE_LOG_DEBUG, "%s: Write special case\n", __fun= c__); + + /* copy the fuse_write_in header after the fuse_in_header = */ + fbuf.mem +=3D out_sg->iov_len; + copy_from_iov(&fbuf, 1, out_sg + 1); + fbuf.mem -=3D out_sg->iov_len; + fbuf.size =3D out_sg[0].iov_len + out_sg[1].iov_len; + + /* Allocate the bufv, with space for the rest of the iov */ + allocated_bufv =3D true; + pbufv =3D malloc(sizeof(struct fuse_bufvec) + + sizeof(struct fuse_buf) * (out_num - 2)); + if (!pbufv) { + vu_queue_unpop(dev, q, elem, 0); + free(elem); + fuse_log(FUSE_LOG_ERR, "%s: pbufv malloc failed\n", + __func__); + goto out; + } + + pbufv->count =3D 1; + pbufv->buf[0] =3D fbuf; + + size_t iovindex, pbufvindex; + iovindex =3D 2; /* 2 headers, separate iovs */ + pbufvindex =3D 1; /* 2 headers, 1 fusebuf */ + + for (; iovindex < out_num; iovindex++, pbufvindex++) { + pbufv->count++; + pbufv->buf[pbufvindex].pos =3D ~0; /* Dummy */ + pbufv->buf[pbufvindex].flags =3D 0; + pbufv->buf[pbufvindex].mem =3D out_sg[iovindex].iov_ba= se; + pbufv->buf[pbufvindex].size =3D out_sg[iovindex].iov_l= en; + } + } else { + /* Normal (non fast write) path */ + + /* Copy the rest of the buffer */ + fbuf.mem +=3D out_sg->iov_len; + copy_from_iov(&fbuf, out_num - 1, out_sg + 1); + fbuf.mem -=3D out_sg->iov_len; + fbuf.size =3D out_len; =20 - /* TODO! Endianness of header */ + /* TODO! Endianness of header */ =20 - /* TODO: Add checks for fuse_session_exited */ - struct fuse_bufvec bufv =3D { .buf[0] =3D fbuf, .count =3D 1 }; - fuse_session_process_buf_int(se, &bufv, &ch); + /* TODO: Add checks for fuse_session_exited */ + bufv.buf[0] =3D fbuf; + bufv.count =3D 1; + pbufv =3D &bufv; + } + pbufv->idx =3D 0; + pbufv->off =3D 0; + fuse_session_process_buf_int(se, pbufv, &ch); + + if (allocated_bufv) { + free(pbufv); + } =20 if (!qi->reply_sent) { fuse_log(FUSE_LOG_DEBUG, "%s: elem %d no reply sent\n", @@ -514,6 +580,7 @@ static void *fv_queue_thread(void *opaque) elem =3D NULL; } } +out: pthread_mutex_destroy(&ch.lock); free(fbuf.mem); =20 --=20 2.23.0