From patchwork Thu Jan 23 11:57:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Dr. David Alan Gilbert" X-Patchwork-Id: 1227950 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=VPyAZAGX; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 483NNL1FH0z9sP3 for ; Fri, 24 Jan 2020 00:26:58 +1100 (AEDT) Received: from localhost ([::1]:57022 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iucVb-0001jW-Aa for incoming@patchwork.ozlabs.org; Thu, 23 Jan 2020 08:26:55 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:40618) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iub9B-0002Vv-49 for qemu-devel@nongnu.org; Thu, 23 Jan 2020 06:59:42 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iub99-0005Es-Mq for qemu-devel@nongnu.org; Thu, 23 Jan 2020 06:59:40 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:37964 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iub98-0005EN-U8 for qemu-devel@nongnu.org; Thu, 23 Jan 2020 06:59:39 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1579780778; 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=BAgKUoDOCYqWYhUiYqdEzmNdZ2gs3y+kHjopAWZ7RIY=; b=VPyAZAGXFcGpdoq+IRsXO7Q54rDlLUZMG8fexEZeyAcVMTpbM91+LnWBtIEfaStapOcUxR Xqw/F4HrY6V1seAD/ESrI8N8IG3Nhpy4M0/lb7+1n11+Pcod5Qu7/uP7uS0cOKcAL8ttx3 RV9cPtpvHh1Y8qNaHb4Fk29NK9pjwKE= 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-29-L8I4UWjvN7OwzS7v7H7KBQ-1; Thu, 23 Jan 2020 06:59:37 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 66C32DB60 for ; Thu, 23 Jan 2020 11:59:36 +0000 (UTC) Received: from dgilbert-t580.localhost (unknown [10.36.118.0]) by smtp.corp.redhat.com (Postfix) with ESMTP id B38051CB; Thu, 23 Jan 2020 11:59:35 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, stefanha@redhat.com Subject: [PULL 042/111] virtiofsd: Pass write iov's all the way through Date: Thu, 23 Jan 2020 11:57:32 +0000 Message-Id: <20200123115841.138849-43-dgilbert@redhat.com> In-Reply-To: <20200123115841.138849-1-dgilbert@redhat.com> References: <20200123115841.138849-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: L8I4UWjvN7OwzS7v7H7KBQ-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 207.211.31.120 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" 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 Reviewed-by: Xiao Yang 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 fd588a4829..872968f2c8 100644 --- a/tools/virtiofsd/fuse_virtio.c +++ b/tools/virtiofsd/fuse_virtio.c @@ -454,6 +454,10 @@ static void *fv_queue_thread(void *opaque) __func__, qi->qidx, (size_t)evalue, in_bytes, out_bytes); while (1) { + bool allocated_bufv = 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 @@ -495,14 +499,76 @@ static void *fv_queue_thread(void *opaque) __func__, elem->index); assert(0); /* TODO */ } - copy_from_iov(&fbuf, out_num, out_sg); - fbuf.size = 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 == sizeof(struct fuse_in_header) && + ((struct fuse_in_header *)fbuf.mem)->opcode == FUSE_WRITE && + out_sg[1].iov_len == 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", __func__); + + /* copy the fuse_write_in header after the fuse_in_header */ + fbuf.mem += out_sg->iov_len; + copy_from_iov(&fbuf, 1, out_sg + 1); + fbuf.mem -= out_sg->iov_len; + fbuf.size = out_sg[0].iov_len + out_sg[1].iov_len; + + /* Allocate the bufv, with space for the rest of the iov */ + allocated_bufv = true; + pbufv = 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 = 1; + pbufv->buf[0] = fbuf; + + size_t iovindex, pbufvindex; + iovindex = 2; /* 2 headers, separate iovs */ + pbufvindex = 1; /* 2 headers, 1 fusebuf */ + + for (; iovindex < out_num; iovindex++, pbufvindex++) { + pbufv->count++; + pbufv->buf[pbufvindex].pos = ~0; /* Dummy */ + pbufv->buf[pbufvindex].flags = 0; + pbufv->buf[pbufvindex].mem = out_sg[iovindex].iov_base; + pbufv->buf[pbufvindex].size = out_sg[iovindex].iov_len; + } + } else { + /* Normal (non fast write) path */ + + /* Copy the rest of the buffer */ + fbuf.mem += out_sg->iov_len; + copy_from_iov(&fbuf, out_num - 1, out_sg + 1); + fbuf.mem -= out_sg->iov_len; + fbuf.size = out_len; - /* TODO! Endianness of header */ + /* TODO! Endianness of header */ - /* TODO: Add checks for fuse_session_exited */ - struct fuse_bufvec bufv = { .buf[0] = fbuf, .count = 1 }; - fuse_session_process_buf_int(se, &bufv, &ch); + /* TODO: Add checks for fuse_session_exited */ + bufv.buf[0] = fbuf; + bufv.count = 1; + pbufv = &bufv; + } + pbufv->idx = 0; + pbufv->off = 0; + fuse_session_process_buf_int(se, pbufv, &ch); + + if (allocated_bufv) { + free(pbufv); + } if (!qi->reply_sent) { fuse_log(FUSE_LOG_DEBUG, "%s: elem %d no reply sent\n", @@ -516,6 +582,7 @@ static void *fv_queue_thread(void *opaque) elem = NULL; } } +out: pthread_mutex_destroy(&ch.lock); free(fbuf.mem);