From nobody Fri Nov 7 14:31:56 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.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; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1548350776015859.2703433340473; Thu, 24 Jan 2019 09:26:16 -0800 (PST) Received: from localhost ([127.0.0.1]:57417 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gmila-0006Zr-LQ for importer@patchew.org; Thu, 24 Jan 2019 12:26:14 -0500 Received: from eggs.gnu.org ([209.51.188.92]:34681) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gmijB-0004pM-Nw for qemu-devel@nongnu.org; Thu, 24 Jan 2019 12:23:47 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gmij9-0000oD-DP for qemu-devel@nongnu.org; Thu, 24 Jan 2019 12:23:45 -0500 Received: from mx1.redhat.com ([209.132.183.28]:58270) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gmij9-0000hx-2z for qemu-devel@nongnu.org; Thu, 24 Jan 2019 12:23:43 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 592F14025C; Thu, 24 Jan 2019 17:23:34 +0000 (UTC) Received: from steredhat.redhat.com (ovpn-117-40.ams2.redhat.com [10.36.117.40]) by smtp.corp.redhat.com (Postfix) with ESMTP id 123577B527; Thu, 24 Jan 2019 17:23:31 +0000 (UTC) From: Stefano Garzarella To: qemu-devel@nongnu.org Date: Thu, 24 Jan 2019 18:23:22 +0100 Message-Id: <20190124172323.230296-2-sgarzare@redhat.com> In-Reply-To: <20190124172323.230296-1-sgarzare@redhat.com> References: <20190124172323.230296-1-sgarzare@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Thu, 24 Jan 2019 17:23:34 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH RFC 1/2] virtio-blk: add DISCARD and WRITE ZEROES features X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Laurent Vivier , Kevin Wolf , Thomas Huth , qemu-block@nongnu.org, "Michael S. Tsirkin" , Max Reitz , Stefan Hajnoczi , Paolo Bonzini Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" This patch adds the support of DISCARD and WRITE ZEROES commands, that have been introduced in the virtio-blk protocol to have better performance when using SSD backend. Signed-off-by: Stefano Garzarella --- hw/block/virtio-blk.c | 79 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 79 insertions(+) diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index f208c6ddb9..8850957751 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -145,6 +145,25 @@ out: aio_context_release(blk_get_aio_context(s->conf.conf.blk)); } =20 +static void virtio_blk_discard_wzeroes_complete(void *opaque, int ret) +{ + VirtIOBlockReq *req =3D opaque; + VirtIOBlock *s =3D req->dev; + + aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); + if (ret) { + if (virtio_blk_handle_rw_error(req, -ret, 0)) { + goto out; + } + } + + virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); + virtio_blk_free_request(req); + +out: + aio_context_release(blk_get_aio_context(s->conf.conf.blk)); +} + #ifdef __linux__ =20 typedef struct { @@ -584,6 +603,56 @@ static int virtio_blk_handle_request(VirtIOBlockReq *r= eq, MultiReqBuffer *mrb) virtio_blk_free_request(req); break; } + /* + * VIRTIO_BLK_T_DISCARD and VIRTIO_BLK_T_WRITE_ZEROES are defined with + * VIRTIO_BLK_T_OUT flag set. We masked this flag in the switch statem= ent, + * so we must mask it for these requests, then we will check the type. + */ + case VIRTIO_BLK_T_DISCARD & ~VIRTIO_BLK_T_OUT: + case VIRTIO_BLK_T_WRITE_ZEROES & ~VIRTIO_BLK_T_OUT: + { + struct virtio_blk_discard_write_zeroes dwz_hdr; + uint64_t sector; + int bytes; + + if (unlikely(iov_to_buf(out_iov, out_num, 0, &dwz_hdr, + sizeof(dwz_hdr)) !=3D sizeof(dwz_hdr))) { + virtio_error(vdev, "virtio-blk discard/wzeroes header too shor= t"); + return -1; + } + + sector =3D virtio_ldq_p(VIRTIO_DEVICE(req->dev), &dwz_hdr.sector); + bytes =3D virtio_ldl_p(VIRTIO_DEVICE(req->dev), + &dwz_hdr.num_sectors) << BDRV_SECTOR_BITS; + + if (!virtio_blk_sect_range_ok(req->dev, sector, bytes)) { + virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR); + virtio_blk_free_request(req); + return 0; + } + + if ((type & ~(VIRTIO_BLK_T_BARRIER)) =3D=3D VIRTIO_BLK_T_DISCARD) { + blk_aio_pdiscard(req->dev->blk, sector << BDRV_SECTOR_BITS, by= tes, + virtio_blk_discard_wzeroes_complete, req); + } else if ((type & ~(VIRTIO_BLK_T_BARRIER)) =3D=3D + VIRTIO_BLK_T_WRITE_ZEROES) { + int flags =3D 0; + + if (virtio_ldl_p(VIRTIO_DEVICE(req->dev), &dwz_hdr.flags) & + VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP) { + flags |=3D BDRV_REQ_MAY_UNMAP; + } + + blk_aio_pwrite_zeroes(req->dev->blk, sector << BDRV_SECTOR_BIT= S, + bytes, flags, + virtio_blk_discard_wzeroes_complete, req= ); + } else { /* Unsupported if VIRTIO_BLK_T_OUT is not set */ + virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP); + virtio_blk_free_request(req); + } + + break; + } default: virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP); virtio_blk_free_request(req); @@ -763,6 +832,14 @@ static void virtio_blk_update_config(VirtIODevice *vde= v, uint8_t *config) blkcfg.alignment_offset =3D 0; blkcfg.wce =3D blk_enable_write_cache(s->blk); virtio_stw_p(vdev, &blkcfg.num_queues, s->conf.num_queues); + virtio_stl_p(vdev, &blkcfg.max_discard_sectors, BDRV_REQUEST_MAX_SECTO= RS); + virtio_stl_p(vdev, &blkcfg.max_discard_seg, 1); + virtio_stl_p(vdev, &blkcfg.discard_sector_alignment, + blk_size >> BDRV_SECTOR_BITS); + virtio_stl_p(vdev, &blkcfg.max_write_zeroes_sectors, + BDRV_REQUEST_MAX_SECTORS); + virtio_stl_p(vdev, &blkcfg.max_write_zeroes_seg, 1); + blkcfg.write_zeroes_may_unmap =3D 1; memcpy(config, &blkcfg, sizeof(struct virtio_blk_config)); } =20 @@ -787,6 +864,8 @@ static uint64_t virtio_blk_get_features(VirtIODevice *v= dev, uint64_t features, virtio_add_feature(&features, VIRTIO_BLK_F_GEOMETRY); virtio_add_feature(&features, VIRTIO_BLK_F_TOPOLOGY); virtio_add_feature(&features, VIRTIO_BLK_F_BLK_SIZE); + virtio_add_feature(&features, VIRTIO_BLK_F_DISCARD); + virtio_add_feature(&features, VIRTIO_BLK_F_WRITE_ZEROES); if (virtio_has_feature(features, VIRTIO_F_VERSION_1)) { if (s->conf.scsi) { error_setg(errp, "Please set scsi=3Doff for virtio-blk devices= in order to use virtio 1.0"); --=20 2.20.1 From nobody Fri Nov 7 14:31:56 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.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; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1548350979518381.1593922645866; Thu, 24 Jan 2019 09:29:39 -0800 (PST) Received: from localhost ([127.0.0.1]:57435 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gmior-0007vy-M6 for importer@patchew.org; Thu, 24 Jan 2019 12:29:37 -0500 Received: from eggs.gnu.org ([209.51.188.92]:36141) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gmio4-0007aN-FB for qemu-devel@nongnu.org; Thu, 24 Jan 2019 12:28:49 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gmio3-0003dM-GC for qemu-devel@nongnu.org; Thu, 24 Jan 2019 12:28:48 -0500 Received: from mx1.redhat.com ([209.132.183.28]:38780) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gmij8-0000jR-Vu; Thu, 24 Jan 2019 12:23:43 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 08868A1E41; Thu, 24 Jan 2019 17:23:37 +0000 (UTC) Received: from steredhat.redhat.com (ovpn-117-40.ams2.redhat.com [10.36.117.40]) by smtp.corp.redhat.com (Postfix) with ESMTP id AC007749C0; Thu, 24 Jan 2019 17:23:34 +0000 (UTC) From: Stefano Garzarella To: qemu-devel@nongnu.org Date: Thu, 24 Jan 2019 18:23:23 +0100 Message-Id: <20190124172323.230296-3-sgarzare@redhat.com> In-Reply-To: <20190124172323.230296-1-sgarzare@redhat.com> References: <20190124172323.230296-1-sgarzare@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Thu, 24 Jan 2019 17:23:37 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH RFC 2/2] tests/virtio-blk: add test for WRITE_ZEROES command X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Laurent Vivier , Kevin Wolf , Thomas Huth , qemu-block@nongnu.org, "Michael S. Tsirkin" , Max Reitz , Stefan Hajnoczi , Paolo Bonzini Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" If the WRITE_ZEROES feature is enabled, we check this command in the test_basic(). Signed-off-by: Stefano Garzarella --- tests/virtio-blk-test.c | 63 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) diff --git a/tests/virtio-blk-test.c b/tests/virtio-blk-test.c index 04c608764b..8cabbcb85a 100644 --- a/tests/virtio-blk-test.c +++ b/tests/virtio-blk-test.c @@ -231,6 +231,69 @@ static void test_basic(QVirtioDevice *dev, QGuestAlloc= ator *alloc, =20 guest_free(alloc, req_addr); =20 + if (features & (1u << VIRTIO_BLK_F_WRITE_ZEROES)) { + struct virtio_blk_discard_write_zeroes *dwz_hdr; + void *expected; + + /* + * WRITE_ZEROES request on the same sector of previous test where + * we wrote "TEST". + */ + req.type =3D VIRTIO_BLK_T_WRITE_ZEROES; + req.data =3D g_malloc0(512); + dwz_hdr =3D (struct virtio_blk_discard_write_zeroes *)req.data; + dwz_hdr->sector =3D 0; + dwz_hdr->num_sectors =3D 1; + dwz_hdr->flags =3D 0; + + req_addr =3D virtio_blk_request(alloc, dev, &req, 512); + + g_free(req.data); + + free_head =3D qvirtqueue_add(vq, req_addr, 16, false, true); + qvirtqueue_add(vq, req_addr + 16, 512, false, true); + qvirtqueue_add(vq, req_addr + 528, 1, true, false); + + qvirtqueue_kick(dev, vq, free_head); + + qvirtio_wait_used_elem(dev, vq, free_head, NULL, + QVIRTIO_BLK_TIMEOUT_US); + status =3D readb(req_addr + 528); + g_assert_cmpint(status, =3D=3D, 0); + + guest_free(alloc, req_addr); + + /* Read request to check if the sector contains all zeroes */ + req.type =3D VIRTIO_BLK_T_IN; + req.ioprio =3D 1; + req.sector =3D 0; + req.data =3D g_malloc0(512); + + req_addr =3D virtio_blk_request(alloc, dev, &req, 512); + + g_free(req.data); + + free_head =3D qvirtqueue_add(vq, req_addr, 16, false, true); + qvirtqueue_add(vq, req_addr + 16, 512, true, true); + qvirtqueue_add(vq, req_addr + 528, 1, true, false); + + qvirtqueue_kick(dev, vq, free_head); + + qvirtio_wait_used_elem(dev, vq, free_head, NULL, + QVIRTIO_BLK_TIMEOUT_US); + status =3D readb(req_addr + 528); + g_assert_cmpint(status, =3D=3D, 0); + + data =3D g_malloc(512); + expected =3D g_malloc0(512); + memread(req_addr + 16, data, 512); + g_assert_cmpmem(data, 512, expected, 512); + g_free(expected); + g_free(data); + + guest_free(alloc, req_addr); + } + if (features & (1u << VIRTIO_F_ANY_LAYOUT)) { /* Write and read with 2 descriptor layout */ /* Write request */ --=20 2.20.1