From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:51461) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gpGZu-0006HT-Hk for qemu-devel@nongnu.org; Thu, 31 Jan 2019 12:56:43 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gpGZm-0005EY-Ip for qemu-devel@nongnu.org; Thu, 31 Jan 2019 12:56:37 -0500 From: Kevin Wolf Date: Thu, 31 Jan 2019 18:55:46 +0100 Message-Id: <20190131175549.11691-9-kwolf@redhat.com> In-Reply-To: <20190131175549.11691-1-kwolf@redhat.com> References: <20190131175549.11691-1-kwolf@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [RFC PATCH 08/11] qcow2: Add basic data-file infrastructure List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: kwolf@redhat.com, mreitz@redhat.com, eblake@redhat.com, qemu-devel@nongnu.org This adds a .bdrv_open option to specify the external data file node. Signed-off-by: Kevin Wolf --- qapi/block-core.json | 3 ++- block/qcow2.h | 4 +++- block/qcow2.c | 25 +++++++++++++++++++++++-- 3 files changed, 28 insertions(+), 4 deletions(-) diff --git a/qapi/block-core.json b/qapi/block-core.json index 7f6b4b3ddd..fc46396079 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -2928,7 +2928,8 @@ '*l2-cache-entry-size': 'int', '*refcount-cache-size': 'int', '*cache-clean-interval': 'int', - '*encrypt': 'BlockdevQcow2Encryption' } } + '*encrypt': 'BlockdevQcow2Encryption', + '*data-file': 'BlockdevRef' } } =20 ## # @SshHostKeyCheckMode: diff --git a/block/qcow2.h b/block/qcow2.h index c161970882..e2114900b4 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -91,6 +91,7 @@ =20 #define DEFAULT_CLUSTER_SIZE 65536 =20 +#define QCOW2_OPT_DATA_FILE "data-file" #define QCOW2_OPT_LAZY_REFCOUNTS "lazy-refcounts" #define QCOW2_OPT_DISCARD_REQUEST "pass-discard-request" #define QCOW2_OPT_DISCARD_SNAPSHOT "pass-discard-snapshot" @@ -205,7 +206,8 @@ enum { QCOW2_INCOMPAT_DATA_FILE =3D 1 << QCOW2_INCOMPAT_DATA_FILE_BI= TNR, =20 QCOW2_INCOMPAT_MASK =3D QCOW2_INCOMPAT_DIRTY - | QCOW2_INCOMPAT_CORRUPT, + | QCOW2_INCOMPAT_CORRUPT + | QCOW2_INCOMPAT_DATA_FILE, }; =20 /* Compatible feature bits */ diff --git a/block/qcow2.c b/block/qcow2.c index ac9934b3ed..376232d3f0 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -1441,8 +1441,22 @@ static int coroutine_fn qcow2_do_open(BlockDriverS= tate *bs, QDict *options, goto fail; } =20 - /* TODO Open external data file */ - s->data_file =3D bs->file; + /* Open external data file */ + if (s->incompatible_features & QCOW2_INCOMPAT_DATA_FILE) { + s->data_file =3D bdrv_open_child(NULL, options, "data-file", bs, + &child_file, false, errp); + if (!s->data_file) { + ret =3D -EINVAL; + goto fail; + } + } else if (qdict_get(options, QCOW2_OPT_DATA_FILE)) { + error_setg(errp, "'data-file' can only be set for images with an= " + "external data file"); + ret =3D -EINVAL; + goto fail; + } else { + s->data_file =3D bs->file; + } =20 /* qcow2_read_extension may have set up the crypto context * if the crypt method needs a header region, some methods @@ -1613,6 +1627,9 @@ static int coroutine_fn qcow2_do_open(BlockDriverSt= ate *bs, QDict *options, return ret; =20 fail: + if (has_data_file(bs)) { + bdrv_unref_child(bs, s->data_file); + } g_free(s->unknown_header_fields); cleanup_unknown_header_ext(bs); qcow2_free_snapshots(bs); @@ -2232,6 +2249,10 @@ static void qcow2_close(BlockDriverState *bs) g_free(s->image_backing_file); g_free(s->image_backing_format); =20 + if (has_data_file(bs)) { + bdrv_unref_child(bs, s->data_file); + } + qcow2_refcount_close(bs); qcow2_free_snapshots(bs); } --=20 2.20.1