diff options
author | Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> | 2021-08-24 11:38:32 +0300 |
---|---|---|
committer | Hanna Reitz <hreitz@redhat.com> | 2021-09-01 14:03:47 +0200 |
commit | 3860c0201924d9f7f9b125b8bdda8a8627de4a08 (patch) | |
tree | 87e548245ee4ccb1fbb2de505cbcec8b0092eb6d /block/copy-before-write.c | |
parent | b518e9e9ef7a28aa559a05d44dd734e83ae75f9d (diff) |
block/copy-before-write: relax permission requirements when no parents
We are going to publish copy-before-write filter. So, user should be
able to create it with blockdev-add first, specifying both filtered and
target children. And then do blockdev-reopen, to actually insert the
filter where needed.
Currently, filter unshares write permission unconditionally on source
node. It's good, but it will not allow to do blockdev-add. So, let's
relax restrictions when filter doesn't have any parent.
Test output is modified, as now permission conflict happens only when
job creates a blk parent for filter node.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20210824083856.17408-11-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Diffstat (limited to 'block/copy-before-write.c')
-rw-r--r-- | block/copy-before-write.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/block/copy-before-write.c b/block/copy-before-write.c index a7996d54db..2a51cc64e4 100644 --- a/block/copy-before-write.c +++ b/block/copy-before-write.c @@ -142,10 +142,12 @@ static void cbw_child_perm(BlockDriverState *bs, BdrvChild *c, bdrv_default_perms(bs, c, role, reopen_queue, perm, shared, nperm, nshared); - if (perm & BLK_PERM_WRITE) { - *nperm = *nperm | BLK_PERM_CONSISTENT_READ; + if (!QLIST_EMPTY(&bs->parents)) { + if (perm & BLK_PERM_WRITE) { + *nperm = *nperm | BLK_PERM_CONSISTENT_READ; + } + *nshared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE); } - *nshared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE); } } |