From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56079) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VPCdw-000655-CH for qemu-devel@nongnu.org; Thu, 26 Sep 2013 10:34:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VPCdl-0005mf-BJ for qemu-devel@nongnu.org; Thu, 26 Sep 2013 10:34:12 -0400 Received: from nodalink.pck.nerim.net ([62.212.105.220]:39645 helo=paradis.irqsave.net) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VPCdk-0005mS-R3 for qemu-devel@nongnu.org; Thu, 26 Sep 2013 10:34:01 -0400 From: =?UTF-8?q?Beno=C3=AEt=20Canet?= Date: Thu, 26 Sep 2013 16:33:49 +0200 Message-Id: <1380206029-9740-2-git-send-email-benoit@irqsave.net> In-Reply-To: <1380206029-9740-1-git-send-email-benoit@irqsave.net> References: <1380206029-9740-1-git-send-email-benoit@irqsave.net> Subject: [Qemu-devel] [PATCH V2] block: Add BlockDriver.bdrv_check_ext_snapshot. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, jcody@redhat.com, =?UTF-8?q?Beno=C3=AEt=20Canet?= , stefanha@redhat.com This field is used by blkverify to disable external snapshots creation. I will also be used by block filters like quorum to disable external snapshots creation. Signed-off-by: Benoit Canet --- block.c | 14 ++++++++++++++ block/blkverify.c | 2 ++ blockdev.c | 5 +++++ include/block/block.h | 7 +++++++ include/block/block_int.h | 8 ++++++++ 5 files changed, 36 insertions(+) diff --git a/block.c b/block.c index 4833b37..4da6fd9 100644 --- a/block.c +++ b/block.c @@ -4632,3 +4632,17 @@ int bdrv_amend_options(BlockDriverState *bs, QEMUOptionParameter *options) } return bs->drv->bdrv_amend_options(bs, options); } + +bool bdrv_check_ext_snapshot(BlockDriverState *bs) +{ + /* external snashots are enabled by defaults */ + if (!bs->drv->bdrv_check_ext_snapshot) { + return true; + } + return bs->drv->bdrv_check_ext_snapshot(bs); +} + +bool bdrv_forbid_ext_snapshot(BlockDriverState *bs) +{ + return false; +} diff --git a/block/blkverify.c b/block/blkverify.c index 2077d8a..c548923 100644 --- a/block/blkverify.c +++ b/block/blkverify.c @@ -313,6 +313,8 @@ static BlockDriver bdrv_blkverify = { .bdrv_aio_readv = blkverify_aio_readv, .bdrv_aio_writev = blkverify_aio_writev, .bdrv_aio_flush = blkverify_aio_flush, + + .bdrv_check_ext_snapshot = bdrv_forbid_ext_snapshot, }; static void bdrv_blkverify_init(void) diff --git a/blockdev.c b/blockdev.c index 8aa66a9..5c16f1b 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1131,6 +1131,11 @@ static void external_snapshot_prepare(BlkTransactionState *common, } } + if (!bdrv_check_ext_snapshot(state->old_bs)) { + error_set(errp, QERR_FEATURE_DISABLED, "snapshot"); + return; + } + flags = state->old_bs->open_flags; /* create new image w/backing file */ diff --git a/include/block/block.h b/include/block/block.h index f808550..df19610 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -244,6 +244,13 @@ int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); int bdrv_amend_options(BlockDriverState *bs_new, QEMUOptionParameter *options); +/* external snapshots */ + +/* return true if external snapshot is allowed, false if not */ +bool bdrv_check_ext_snapshot(BlockDriverState *bs); +/* helper used to forbid external snapshots like in blkverify */ +bool bdrv_forbid_ext_snapshot(BlockDriverState *bs); + /* async block I/O */ typedef void BlockDriverDirtyHandler(BlockDriverState *bs, int64_t sector, int sector_num); diff --git a/include/block/block_int.h b/include/block/block_int.h index 211087a..cb92355 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -67,6 +67,14 @@ typedef struct BdrvTrackedRequest { struct BlockDriver { const char *format_name; int instance_size; + + /* if not defined external snapshots are allowed + * if return true external snapshots are allowed + * if return false external snapshots are not allowed + * future block filters will query their children to build the response + */ + bool (*bdrv_check_ext_snapshot)(BlockDriverState *bs); + int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename); int (*bdrv_probe_device)(const char *filename); -- 1.8.1.2