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authorFam Zheng <famz@redhat.com>2018-08-14 15:25:51 +0800
committerKevin Wolf <kwolf@redhat.com>2018-08-15 12:50:39 +0200
commit497da8236ab2663a8108858ba7ea59aac21c5fe6 (patch)
tree47f46c340b10a95cc696004a34794abb89794991
parent25b8e4db7f3baca47244ccd945eb62b32a6e2019 (diff)
luks: Allow share-rw=on
Format drivers such as qcow2 don't allow sharing the same image between two QEMU instances in order to prevent image corruptions, because of metadata cache. LUKS driver don't modify metadata except for when creating image, so it is safe to relax the permission. This makes share-rw=on property work on virtual devices. Suggested-by: Daniel P. Berrangé <berrange@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
-rw-r--r--block/crypto.c4
1 files changed, 3 insertions, 1 deletions
diff --git a/block/crypto.c b/block/crypto.c
index 146d81c90a..33ee01bebd 100644
--- a/block/crypto.c
+++ b/block/crypto.c
@@ -627,7 +627,9 @@ BlockDriver bdrv_crypto_luks = {
.bdrv_probe = block_crypto_probe_luks,
.bdrv_open = block_crypto_open_luks,
.bdrv_close = block_crypto_close,
- .bdrv_child_perm = bdrv_format_default_perms,
+ /* This driver doesn't modify LUKS metadata except when creating image.
+ * Allow share-rw=on as a special case. */
+ .bdrv_child_perm = bdrv_filter_default_perms,
.bdrv_co_create = block_crypto_co_create_luks,
.bdrv_co_create_opts = block_crypto_co_create_opts_luks,
.bdrv_co_truncate = block_crypto_co_truncate,