From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42957) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VUeIN-00078Q-Tb for qemu-devel@nongnu.org; Fri, 11 Oct 2013 11:06:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VUeII-0005Gs-PG for qemu-devel@nongnu.org; Fri, 11 Oct 2013 11:06:27 -0400 Received: from mx1.redhat.com ([209.132.183.28]:24242) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VUeII-0005Gk-HA for qemu-devel@nongnu.org; Fri, 11 Oct 2013 11:06:22 -0400 From: Kevin Wolf Date: Fri, 11 Oct 2013 17:05:07 +0200 Message-Id: <1381503951-27985-18-git-send-email-kwolf@redhat.com> In-Reply-To: <1381503951-27985-1-git-send-email-kwolf@redhat.com> References: <1381503951-27985-1-git-send-email-kwolf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PULL 17/61] block: Add BlockDriver.bdrv_check_ext_snapshot. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: anthony@codemonkey.ws Cc: kwolf@redhat.com, qemu-devel@nongnu.org From: Beno=C3=AEt Canet This field is used by blkverify to disable external snapshots creation. It will also be used by block filters like quorum to disable external snapshot creation. Signed-off-by: Benoit Canet Reviewed-by: Max Reitz Signed-off-by: Kevin Wolf --- block.c | 19 +++++++++++++++++++ block/blkverify.c | 2 ++ blockdev.c | 5 +++++ include/block/block.h | 14 ++++++++++++++ include/block/block_int.h | 6 ++++++ 5 files changed, 46 insertions(+) diff --git a/block.c b/block.c index d86efad..beea027 100644 --- a/block.c +++ b/block.c @@ -4647,3 +4647,22 @@ int bdrv_amend_options(BlockDriverState *bs, QEMUO= ptionParameter *options) } return bs->drv->bdrv_amend_options(bs, options); } + +ExtSnapshotPerm bdrv_check_ext_snapshot(BlockDriverState *bs) +{ + if (bs->drv->bdrv_check_ext_snapshot) { + return bs->drv->bdrv_check_ext_snapshot(bs); + } + + if (bs->file && bs->file->drv && bs->file->drv->bdrv_check_ext_snaps= hot) { + return bs->file->drv->bdrv_check_ext_snapshot(bs); + } + + /* external snapshots are allowed by default */ + return EXT_SNAPSHOT_ALLOWED; +} + +ExtSnapshotPerm bdrv_check_ext_snapshot_forbidden(BlockDriverState *bs) +{ + return EXT_SNAPSHOT_FORBIDDEN; +} diff --git a/block/blkverify.c b/block/blkverify.c index bff95d2..1e8e6d9 100644 --- a/block/blkverify.c +++ b/block/blkverify.c @@ -417,6 +417,8 @@ static BlockDriver bdrv_blkverify =3D { .bdrv_aio_readv =3D blkverify_aio_readv, .bdrv_aio_writev =3D blkverify_aio_writev, .bdrv_aio_flush =3D blkverify_aio_flush, + + .bdrv_check_ext_snapshot =3D bdrv_check_ext_snapshot_forbidden, }; =20 static void bdrv_blkverify_init(void) diff --git a/blockdev.c b/blockdev.c index 8c83f6f..a91d5a8 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1131,6 +1131,11 @@ static void external_snapshot_prepare(BlkTransacti= onState *common, } } =20 + if (bdrv_check_ext_snapshot(state->old_bs) !=3D EXT_SNAPSHOT_ALLOWED= ) { + error_set(errp, QERR_FEATURE_DISABLED, "snapshot"); + return; + } + flags =3D state->old_bs->open_flags; =20 /* create new image w/backing file */ diff --git a/include/block/block.h b/include/block/block.h index 0d4d5c3..3560deb 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -248,6 +248,20 @@ int bdrv_check(BlockDriverState *bs, BdrvCheckResult= *res, BdrvCheckMode fix); =20 int bdrv_amend_options(BlockDriverState *bs_new, QEMUOptionParameter *op= tions); =20 +/* external snapshots */ + +typedef enum { + EXT_SNAPSHOT_ALLOWED, + EXT_SNAPSHOT_FORBIDDEN, +} ExtSnapshotPerm; + +/* return EXT_SNAPSHOT_ALLOWED if external snapshot is allowed + * return EXT_SNAPSHOT_FORBIDDEN if external snapshot is forbidden + */ +ExtSnapshotPerm bdrv_check_ext_snapshot(BlockDriverState *bs); +/* helper used to forbid external snapshots like in blkverify */ +ExtSnapshotPerm bdrv_check_ext_snapshot_forbidden(BlockDriverState *bs); + /* async block I/O */ typedef void BlockDriverDirtyHandler(BlockDriverState *bs, int64_t secto= r, int sector_num); diff --git a/include/block/block_int.h b/include/block/block_int.h index 17b26b2..a48731d 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -67,6 +67,12 @@ typedef struct BdrvTrackedRequest { struct BlockDriver { const char *format_name; int instance_size; + + /* if not defined external snapshots are allowed + * future block filters will query their children to build the respo= nse + */ + ExtSnapshotPerm (*bdrv_check_ext_snapshot)(BlockDriverState *bs); + int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *file= name); int (*bdrv_probe_device)(const char *filename); =20 --=20 1.8.1.4