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=-9.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 3A9B4C388F7 for ; Fri, 13 Nov 2020 13:49:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E0F042223F for ; Fri, 13 Nov 2020 13:49:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="d2+G5vX2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726778AbgKMNtY (ORCPT ); Fri, 13 Nov 2020 08:49:24 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:48792 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726878AbgKMNtX (ORCPT ); Fri, 13 Nov 2020 08:49:23 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1605275361; 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=c3r8/B+7cC6X7RvaWGidvwKg/ni8ZPyPCRRKcbTbrJM=; b=d2+G5vX2BiP/wawcjOdClPTejq2pT72TT3bY46lnQYTjrjyb7pcgeOgzboO0xwBSOkzqn0 /QubdIYi+vZLLsrs1YJ/beQQHwSQp7BjcvoJu4ew4XVt1Dmpfr3nv9XSD3vZqoaSH8ohm3 qzCeGL1zCCrwrVY6UsvjxNbM+yI5GNs= 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-397-8jc7Dpz7NXe4sBQBG-oZEQ-1; Fri, 13 Nov 2020 08:49:19 -0500 X-MC-Unique: 8jc7Dpz7NXe4sBQBG-oZEQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 8FAE21882FBD; Fri, 13 Nov 2020 13:49:18 +0000 (UTC) Received: from steredhat.redhat.com (ovpn-114-21.ams2.redhat.com [10.36.114.21]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1C4CA5C1C7; Fri, 13 Nov 2020 13:49:07 +0000 (UTC) From: Stefano Garzarella To: virtualization@lists.linux-foundation.org Cc: Stefan Hajnoczi , Laurent Vivier , linux-kernel@vger.kernel.org, Eli Cohen , Jason Wang , "Michael S. Tsirkin" , Max Gurtovoy Subject: [PATCH RFC 12/12] vdpa_sim_blk: implement ramdisk behaviour Date: Fri, 13 Nov 2020 14:47:12 +0100 Message-Id: <20201113134712.69744-13-sgarzare@redhat.com> In-Reply-To: <20201113134712.69744-1-sgarzare@redhat.com> References: <20201113134712.69744-1-sgarzare@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The previous implementation wrote only the status of each request. This patch implements a more accurate block device simulator, providing a ramdisk-like behavior. Also handle VIRTIO_BLK_T_GET_ID request, always answering the "vdpa_blk_sim" string. Signed-off-by: Stefano Garzarella --- drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 151 +++++++++++++++++++++++---- 1 file changed, 133 insertions(+), 18 deletions(-) diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c index 8e41b3ab98d5..68e74383322f 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c @@ -7,6 +7,7 @@ */ #include +#include #include #include "vdpa_sim.h" @@ -24,10 +25,137 @@ static struct vdpasim *vdpasim_blk_dev; +static int vdpasim_blk_handle_req(struct vdpasim *vdpasim, + struct vdpasim_virtqueue *vq) +{ + size_t wrote = 0, to_read = 0, to_write = 0; + struct virtio_blk_outhdr hdr; + uint8_t status; + uint32_t type; + ssize_t bytes; + loff_t offset; + int i, ret; + + vringh_kiov_cleanup(&vq->riov); + vringh_kiov_cleanup(&vq->wiov); + + ret = vringh_getdesc_iotlb(&vq->vring, &vq->riov, &vq->wiov, + &vq->head, GFP_ATOMIC); + if (ret != 1) + return ret; + + for (i = 0; i < vq->wiov.used; i++) + to_write += vq->wiov.iov[i].iov_len; + to_write -= 1; /* last byte is the status */ + + for (i = 0; i < vq->riov.used; i++) + to_read += vq->riov.iov[i].iov_len; + + bytes = vringh_iov_pull_iotlb(&vq->vring, &vq->riov, &hdr, sizeof(hdr)); + if (bytes != sizeof(hdr)) + return 0; + + to_read -= bytes; + + type = le32_to_cpu(hdr.type); + offset = le64_to_cpu(hdr.sector) << SECTOR_SHIFT; + status = VIRTIO_BLK_S_OK; + + switch (type) { + case VIRTIO_BLK_T_IN: + if (offset + to_write > VDPASIM_BLK_CAPACITY << SECTOR_SHIFT) { + dev_err(&vdpasim->vdpa.dev, + "reading over the capacity - offset: 0x%llx len: 0x%lx\n", + offset, to_write); + status = VIRTIO_BLK_S_IOERR; + break; + } + + bytes = vringh_iov_push_iotlb(&vq->vring, &vq->wiov, + vdpasim->buffer + offset, + to_write); + if (bytes < 0) { + dev_err(&vdpasim->vdpa.dev, + "vringh_iov_push_iotlb() error: %ld offset: 0x%llx len: 0x%lx\n", + bytes, offset, to_write); + status = VIRTIO_BLK_S_IOERR; + break; + } + + wrote += bytes; + break; + + case VIRTIO_BLK_T_OUT: + if (offset + to_read > VDPASIM_BLK_CAPACITY << SECTOR_SHIFT) { + dev_err(&vdpasim->vdpa.dev, + "writing over the capacity - offset: 0x%llx len: 0x%lx\n", + offset, to_read); + status = VIRTIO_BLK_S_IOERR; + break; + } + + bytes = vringh_iov_pull_iotlb(&vq->vring, &vq->riov, + vdpasim->buffer + offset, + to_read); + if (bytes < 0) { + dev_err(&vdpasim->vdpa.dev, + "vringh_iov_pull_iotlb() error: %ld offset: 0x%llx len: 0x%lx\n", + bytes, offset, to_read); + status = VIRTIO_BLK_S_IOERR; + break; + } + break; + + case VIRTIO_BLK_T_GET_ID: { + char id[VIRTIO_BLK_ID_BYTES] = "vdpa_blk_sim"; + + bytes = vringh_iov_push_iotlb(&vq->vring, + &vq->wiov, id, + VIRTIO_BLK_ID_BYTES); + if (bytes < 0) { + dev_err(&vdpasim->vdpa.dev, + "vringh_iov_push_iotlb() error: %ld\n", bytes); + status = VIRTIO_BLK_S_IOERR; + break; + } + + wrote += bytes; + break; + } + + default: + dev_warn(&vdpasim->vdpa.dev, + "Unsupported request type %d\n", type); + status = VIRTIO_BLK_S_IOERR; + break; + } + + /* if VIRTIO_BLK_T_IN or VIRTIO_BLK_T_GET_ID fail, we need to skip + * the remaining bytes to put the status in the last byte + */ + if (to_write - wrote > 0) { + vringh_iov_push_iotlb(&vq->vring, &vq->wiov, NULL, + to_write - wrote); + } + + /* last byte is the status */ + bytes = vringh_iov_push_iotlb(&vq->vring, &vq->wiov, &status, 1); + if (bytes != 1) + return 0; + + wrote += bytes; + + /* Make sure data is wrote before advancing index */ + smp_wmb(); + + vringh_complete_iotlb(&vq->vring, vq->head, wrote); + + return ret; +} + static void vdpasim_blk_work(struct work_struct *work) { struct vdpasim *vdpasim = container_of(work, struct vdpasim, work); - u8 status = VIRTIO_BLK_S_OK; int i; spin_lock(&vdpasim->lock); @@ -41,21 +169,7 @@ static void vdpasim_blk_work(struct work_struct *work) if (!vq->ready) continue; - while (vringh_getdesc_iotlb(&vq->vring, &vq->riov, &vq->wiov, - &vq->head, GFP_ATOMIC) > 0) { - - int write; - - vq->wiov.i = vq->wiov.used - 1; - write = vringh_iov_push_iotlb(&vq->vring, &vq->wiov, &status, 1); - if (write <= 0) - break; - - /* Make sure data is wrote before advancing index */ - smp_wmb(); - - vringh_complete_iotlb(&vq->vring, vq->head, write); - + while (vdpasim_blk_handle_req(vdpasim, vq) > 0) { /* Make sure used is visible before rasing the interrupt. */ smp_wmb(); @@ -67,6 +181,7 @@ static void vdpasim_blk_work(struct work_struct *work) vq->cb(vq->private); local_bh_enable(); } + } out: spin_unlock(&vdpasim->lock); @@ -84,7 +199,7 @@ static void vdpasim_blk_update_config(struct vdpasim *vdpasim) config->num_queues = cpu_to_vdpasim16(vdpasim, VDPASIM_BLK_VQ_NUM); config->min_io_size = cpu_to_vdpasim16(vdpasim, 1); config->opt_io_size = cpu_to_vdpasim32(vdpasim, 1); - config->blk_size = cpu_to_vdpasim32(vdpasim, 512); + config->blk_size = cpu_to_vdpasim32(vdpasim, SECTOR_SIZE); } static int __init vdpasim_blk_init(void) @@ -100,7 +215,7 @@ static int __init vdpasim_blk_init(void) attr.device.update_config = vdpasim_blk_update_config; attr.work_fn = vdpasim_blk_work; - attr.buffer_size = PAGE_SIZE; + attr.buffer_size = VDPASIM_BLK_CAPACITY << SECTOR_SHIFT; vdpasim_blk_dev = vdpasim_create(&attr); if (IS_ERR(vdpasim_blk_dev)) { -- 2.26.2