block/rbd: Add support for reopen()

This adds support for reopen in rbd, for changing between r/w and r/o.

Note, that this is only a flag change, but we will block a change from
r/o to r/w if we are using an RBD internal snapshot.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: d4e87539167ec6527d44c97b164eabcccf96e4f3.1491597120.git.jcody@redhat.com
This commit is contained in:
Jeff Cody 2017-04-07 16:55:32 -04:00
parent 80b61a27c6
commit 56e7cf8df0

View file

@ -668,6 +668,26 @@ failed_opts:
return r;
}
/* Since RBD is currently always opened R/W via the API,
* we just need to check if we are using a snapshot or not, in
* order to determine if we will allow it to be R/W */
static int qemu_rbd_reopen_prepare(BDRVReopenState *state,
BlockReopenQueue *queue, Error **errp)
{
BDRVRBDState *s = state->bs->opaque;
int ret = 0;
if (s->snap && state->flags & BDRV_O_RDWR) {
error_setg(errp,
"Cannot change node '%s' to r/w when using RBD snapshot",
bdrv_get_device_or_node_name(state->bs));
ret = -EINVAL;
}
return ret;
}
static void qemu_rbd_close(BlockDriverState *bs)
{
BDRVRBDState *s = bs->opaque;
@ -1074,6 +1094,7 @@ static BlockDriver bdrv_rbd = {
.bdrv_parse_filename = qemu_rbd_parse_filename,
.bdrv_file_open = qemu_rbd_open,
.bdrv_close = qemu_rbd_close,
.bdrv_reopen_prepare = qemu_rbd_reopen_prepare,
.bdrv_create = qemu_rbd_create,
.bdrv_has_zero_init = bdrv_has_zero_init_1,
.bdrv_get_info = qemu_rbd_getinfo,