From patchwork Mon Aug 6 20:44:44 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 175450 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id B18AE2C009D for ; Tue, 7 Aug 2012 06:45:30 +1000 (EST) Received: from localhost ([::1]:59043 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SyUB6-00009U-OG for incoming@patchwork.ozlabs.org; Mon, 06 Aug 2012 16:45:28 -0400 Received: from eggs.gnu.org ([208.118.235.92]:60119) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SyUAj-0008PN-9d for qemu-devel@nongnu.org; Mon, 06 Aug 2012 16:45:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SyUAh-0004TO-Dp for qemu-devel@nongnu.org; Mon, 06 Aug 2012 16:45:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:64883) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SyUAh-0004RS-5p for qemu-devel@nongnu.org; Mon, 06 Aug 2012 16:45:03 -0400 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q76Kj1LY015359 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Mon, 6 Aug 2012 16:45:01 -0400 Received: from dhcp-5-188.str.redhat.com (vpn1-7-164.ams2.redhat.com [10.36.7.164]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id q76KiqGF002690; Mon, 6 Aug 2012 16:45:00 -0400 From: Kevin Wolf To: anthony@codemonkey.ws Date: Mon, 6 Aug 2012 22:44:44 +0200 Message-Id: <1344285891-6578-6-git-send-email-kwolf@redhat.com> In-Reply-To: <1344285891-6578-1-git-send-email-kwolf@redhat.com> References: <1344285891-6578-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 209.132.183.28 Cc: kwolf@redhat.com, qemu-devel@nongnu.org Subject: [Qemu-devel] [PATCH 05/12] qcow2: introduce dirty bit 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 From: Stefan Hajnoczi This patch adds an incompatible feature bit to mark images that have not been closed cleanly. When a dirty image file is opened a consistency check and repair is performed. Update qemu-iotests 031 and 036 since the extension header size changes when we add feature bit table entries. Signed-off-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf --- block/qcow2.c | 50 +++++++++++++++++++++++++++++++++++++++++-- block/qcow2.h | 8 +++++++ tests/qemu-iotests/031.out | 20 ++++++++-------- tests/qemu-iotests/036.out | 4 +- 4 files changed, 67 insertions(+), 15 deletions(-) diff --git a/block/qcow2.c b/block/qcow2.c index 870148d..7fe1567 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -214,6 +214,27 @@ static void report_unsupported_feature(BlockDriverState *bs, } } +/* + * Clears the dirty bit and flushes before if necessary. Only call this + * function when there are no pending requests, it does not guard against + * concurrent requests dirtying the image. + */ +static int qcow2_mark_clean(BlockDriverState *bs) +{ + BDRVQcowState *s = bs->opaque; + + if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) { + int ret = bdrv_flush(bs); + if (ret < 0) { + return ret; + } + + s->incompatible_features &= ~QCOW2_INCOMPAT_DIRTY; + return qcow2_update_header(bs); + } + return 0; +} + static int qcow2_open(BlockDriverState *bs, int flags) { BDRVQcowState *s = bs->opaque; @@ -287,12 +308,13 @@ static int qcow2_open(BlockDriverState *bs, int flags) s->compatible_features = header.compatible_features; s->autoclear_features = header.autoclear_features; - if (s->incompatible_features != 0) { + if (s->incompatible_features & ~QCOW2_INCOMPAT_MASK) { void *feature_table = NULL; qcow2_read_extensions(bs, header.header_length, ext_end, &feature_table); report_unsupported_feature(bs, feature_table, - s->incompatible_features); + s->incompatible_features & + ~QCOW2_INCOMPAT_MASK); ret = -ENOTSUP; goto fail; } @@ -412,6 +434,22 @@ static int qcow2_open(BlockDriverState *bs, int flags) /* Initialise locks */ qemu_co_mutex_init(&s->lock); + /* Repair image if dirty */ + if ((s->incompatible_features & QCOW2_INCOMPAT_DIRTY) && + !bs->read_only) { + BdrvCheckResult result = {0}; + + ret = qcow2_check_refcounts(bs, &result, BDRV_FIX_ERRORS); + if (ret < 0) { + goto fail; + } + + ret = qcow2_mark_clean(bs); + if (ret < 0) { + goto fail; + } + } + #ifdef DEBUG_ALLOC { BdrvCheckResult result = {0}; @@ -785,6 +823,8 @@ static void qcow2_close(BlockDriverState *bs) qcow2_cache_flush(bs, s->l2_table_cache); qcow2_cache_flush(bs, s->refcount_block_cache); + qcow2_mark_clean(bs); + qcow2_cache_destroy(bs, s->l2_table_cache); qcow2_cache_destroy(bs, s->refcount_block_cache); @@ -949,7 +989,11 @@ int qcow2_update_header(BlockDriverState *bs) /* Feature table */ Qcow2Feature features[] = { - /* no feature defined yet */ + { + .type = QCOW2_FEAT_TYPE_INCOMPATIBLE, + .bit = QCOW2_INCOMPAT_DIRTY_BITNR, + .name = "dirty bit", + }, }; ret = header_ext_add(buf, QCOW2_EXT_MAGIC_FEATURE_TABLE, diff --git a/block/qcow2.h b/block/qcow2.h index 455b6d7..b5fefc0 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -110,6 +110,14 @@ enum { QCOW2_FEAT_TYPE_AUTOCLEAR = 2, }; +/* Incompatible feature bits */ +enum { + QCOW2_INCOMPAT_DIRTY_BITNR = 0, + QCOW2_INCOMPAT_DIRTY = 1 << QCOW2_INCOMPAT_DIRTY_BITNR, + + QCOW2_INCOMPAT_MASK = QCOW2_INCOMPAT_DIRTY, +}; + typedef struct Qcow2Feature { uint8_t type; uint8_t bit; diff --git a/tests/qemu-iotests/031.out b/tests/qemu-iotests/031.out index d3cab30..297b458 100644 --- a/tests/qemu-iotests/031.out +++ b/tests/qemu-iotests/031.out @@ -54,8 +54,8 @@ header_length 72 Header extension: magic 0x6803f857 -length 0 -data '' +length 48 +data Header extension: magic 0x12345678 @@ -68,7 +68,7 @@ No errors were found on the image. magic 0x514649fb version 2 -backing_file_offset 0x98 +backing_file_offset 0xc8 backing_file_size 0x17 cluster_bits 16 size 67108864 @@ -92,8 +92,8 @@ data 'host_device' Header extension: magic 0x6803f857 -length 0 -data '' +length 48 +data Header extension: magic 0x12345678 @@ -155,8 +155,8 @@ header_length 104 Header extension: magic 0x6803f857 -length 0 -data '' +length 48 +data Header extension: magic 0x12345678 @@ -169,7 +169,7 @@ No errors were found on the image. magic 0x514649fb version 3 -backing_file_offset 0xb8 +backing_file_offset 0xe8 backing_file_size 0x17 cluster_bits 16 size 67108864 @@ -193,8 +193,8 @@ data 'host_device' Header extension: magic 0x6803f857 -length 0 -data '' +length 48 +data Header extension: magic 0x12345678 diff --git a/tests/qemu-iotests/036.out b/tests/qemu-iotests/036.out index 6953e37..ca0fda1 100644 --- a/tests/qemu-iotests/036.out +++ b/tests/qemu-iotests/036.out @@ -46,7 +46,7 @@ header_length 104 Header extension: magic 0x6803f857 -length 0 -data '' +length 48 +data *** done