From patchwork Thu Jun 13 11:47:41 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 251060 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id EDF6F2C00A7 for ; Thu, 13 Jun 2013 21:49:56 +1000 (EST) Received: from localhost ([::1]:59969 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Un62M-000878-Rq for incoming@patchwork.ozlabs.org; Thu, 13 Jun 2013 07:49:54 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58983) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Un61j-00080P-Qo for qemu-devel@nongnu.org; Thu, 13 Jun 2013 07:49:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Un61i-0000ch-Og for qemu-devel@nongnu.org; Thu, 13 Jun 2013 07:49:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34902) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Un61i-0000cd-Gc for qemu-devel@nongnu.org; Thu, 13 Jun 2013 07:49:14 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r5DBnDHJ003407 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 13 Jun 2013 07:49:13 -0400 Received: from dhcp-200-207.str.redhat.com (ovpn-116-75.ams2.redhat.com [10.36.116.75]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id r5DBn6Nf007847; Thu, 13 Jun 2013 07:49:12 -0400 From: Kevin Wolf To: qemu-devel@nongnu.org Date: Thu, 13 Jun 2013 13:47:41 +0200 Message-Id: <1371124063-12971-4-git-send-email-kwolf@redhat.com> In-Reply-To: <1371124063-12971-1-git-send-email-kwolf@redhat.com> References: <1371124063-12971-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: kwolf@redhat.com, stefanha@redhat.com Subject: [Qemu-devel] [PATCH 3/5] qcow2: Options to enable discard for freed clusters X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 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-bounces+incoming=patchwork.ozlabs.org@nongnu.org Deleted snapshots are discarded in the image file by default, discard requests take their default from the -drive discard=... option and other places that free clusters must always be enabled explicitly. Signed-off-by: Kevin Wolf --- block/qcow2-refcount.c | 5 +++++ block/qcow2.c | 26 ++++++++++++++++++++++++++ block/qcow2.h | 5 +++++ 3 files changed, 36 insertions(+) diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index 6d35e49..7488988 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -488,6 +488,11 @@ static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, s->free_cluster_index = cluster_index; } refcount_block[block_index] = cpu_to_be16(refcount); + if (refcount == 0 && s->discard_passthrough[type]) { + /* Try discarding, ignore errors */ + /* FIXME Doing this cluster by cluster will be painfully slow */ + bdrv_discard(bs->file, cluster_offset, 1); + } } ret = 0; diff --git a/block/qcow2.c b/block/qcow2.c index e28ea47..62e6753 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -295,6 +295,22 @@ static QemuOptsList qcow2_runtime_opts = { .type = QEMU_OPT_BOOL, .help = "Postpone refcount updates", }, + { + .name = QCOW2_OPT_DISCARD_REQUEST, + .type = QEMU_OPT_BOOL, + .help = "Pass guest discard requests to the layer below", + }, + { + .name = QCOW2_OPT_DISCARD_SNAPSHOT, + .type = QEMU_OPT_BOOL, + .help = "Generate discard requests when snapshot related space " + "is freed", + }, + { + .name = QCOW2_OPT_DISCARD_OTHER, + .type = QEMU_OPT_BOOL, + .help = "Generate discard requests when other clusters are freed", + }, { /* end of list */ } }, }; @@ -532,6 +548,16 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags) s->use_lazy_refcounts = qemu_opt_get_bool(opts, QCOW2_OPT_LAZY_REFCOUNTS, (s->compatible_features & QCOW2_COMPAT_LAZY_REFCOUNTS)); + s->discard_passthrough[QCOW2_DISCARD_NEVER] = false, + s->discard_passthrough[QCOW2_DISCARD_ALWAYS] = true, + s->discard_passthrough[QCOW2_DISCARD_REQUEST] = + qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_REQUEST, + flags & BDRV_O_UNMAP), + s->discard_passthrough[QCOW2_DISCARD_SNAPSHOT] = + qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_SNAPSHOT, true), + s->discard_passthrough[QCOW2_DISCARD_OTHER] = + qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_OTHER, false), + qemu_opts_del(opts); if (s->use_lazy_refcounts && s->qcow_version < 3) { diff --git a/block/qcow2.h b/block/qcow2.h index 64a6479..6f91b9a 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -60,6 +60,9 @@ #define QCOW2_OPT_LAZY_REFCOUNTS "lazy_refcounts" +#define QCOW2_OPT_DISCARD_REQUEST "pass_discard_request" +#define QCOW2_OPT_DISCARD_SNAPSHOT "pass_discard_snapshot" +#define QCOW2_OPT_DISCARD_OTHER "pass_discard_other" typedef struct QCowHeader { uint32_t magic; @@ -187,6 +190,8 @@ typedef struct BDRVQcowState { int qcow_version; bool use_lazy_refcounts; + bool discard_passthrough[QCOW2_DISCARD_MAX]; + uint64_t incompatible_features; uint64_t compatible_features; uint64_t autoclear_features;