From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57269) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cnksN-0008LB-8o for qemu-devel@nongnu.org; Tue, 14 Mar 2017 07:44:28 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cnksM-0006u0-E3 for qemu-devel@nongnu.org; Tue, 14 Mar 2017 07:44:27 -0400 From: Changlong Xie Date: Tue, 14 Mar 2017 19:46:52 +0800 Message-ID: <1489492012-8002-1-git-send-email-xiecl.fnst@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain Subject: [Qemu-devel] [PATCH V1] replication: clarify permissions List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu devel , qemu block , Stefan Hajnoczi , Fam Zheng , Max Reitz , Kevin Wolf Cc: Wen Congyang , zhanghailiang , Changlong Xie , Zhang Chen Even if hidden_disk, secondary_disk are backing files, they all need write permissions in replication scenario. Otherwise we will encouter below exceptions on secondary side during adding nbd server: {'execute': 'nbd-server-add', 'arguments': {'device': 'colo-disk', 'writable': true } } {"error": {"class": "GenericError", "desc": "Conflicts with use by hidden-qcow2-driver as 'backing', which does not allow 'write' on sec-qcow2-driver-for-nbd"}} CC: Zhang Hailiang CC: Zhang Chen CC: Wen Congyang Signed-off-by: Changlong Xie --- block/replication.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/block/replication.c b/block/replication.c index 22f170f..bf3c395 100644 --- a/block/replication.c +++ b/block/replication.c @@ -155,6 +155,18 @@ static void replication_close(BlockDriverState *bs) replication_remove(s->rs); } +static void replication_child_perm(BlockDriverState *bs, BdrvChild *c, + const BdrvChildRole *role, + uint64_t perm, uint64_t shared, + uint64_t *nperm, uint64_t *nshared) +{ + *nperm = *nshared = BLK_PERM_CONSISTENT_READ \ + | BLK_PERM_WRITE \ + | BLK_PERM_WRITE_UNCHANGED; + + return; +} + static int64_t replication_getlength(BlockDriverState *bs) { return bdrv_getlength(bs->file->bs); @@ -660,7 +672,7 @@ BlockDriver bdrv_replication = { .bdrv_open = replication_open, .bdrv_close = replication_close, - .bdrv_child_perm = bdrv_filter_default_perms, + .bdrv_child_perm = replication_child_perm, .bdrv_getlength = replication_getlength, .bdrv_co_readv = replication_co_readv, -- 1.9.3