| Message ID | 1443717273-5280-4-git-send-email-jsnow@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 01/10/2015 18:34, John Snow wrote: > + > + error_setg(&blocker, "Block device(s) are in use by a Block Transaction"); s/Block Transaction/transaction command/ But how can migration start during a transaction? > + ret = migrate_add_blocker(blocker, errp); > + if (ret < 0) { > + goto cleanup_mig; > + } > > QSIMPLEQ_HEAD(snap_bdrv_states, BlkTransactionState) snap_bdrv_states; > QSIMPLEQ_INIT(&snap_bdrv_states); > @@ -1814,6 +1823,9 @@ exit: > } > g_free(state); > } > + cleanup_mig: > + migrate_del_blocker(blocker); > + error_free(blocker);
On 10/01/2015 02:01 PM, Paolo Bonzini wrote: > > > On 01/10/2015 18:34, John Snow wrote: >> + >> + error_setg(&blocker, "Block device(s) are in use by a Block Transaction"); > > s/Block Transaction/transaction command/ > > But how can migration start during a transaction? > Well, it definitely can't now ! :) This is actually more for the other case: The migration starts, and we want to prohibit snapshots and transactions during that period. Together with the patch this depends on, we accomplish that. The workflow of snapshot/transaction-before-migration isn't currently possible. >> + ret = migrate_add_blocker(blocker, errp); >> + if (ret < 0) { >> + goto cleanup_mig; >> + } >> >> QSIMPLEQ_HEAD(snap_bdrv_states, BlkTransactionState) snap_bdrv_states; >> QSIMPLEQ_INIT(&snap_bdrv_states); >> @@ -1814,6 +1823,9 @@ exit: >> } >> g_free(state); >> } >> + cleanup_mig: >> + migrate_del_blocker(blocker); >> + error_free(blocker); >
diff --git a/blockdev.c b/blockdev.c index 32b04b4..231dcf6 100644 --- a/blockdev.c +++ b/blockdev.c @@ -49,6 +49,7 @@ #include "qmp-commands.h" #include "trace.h" #include "sysemu/arch_init.h" +#include "migration/migration.h" static const char *const if_name[IF_COUNT] = { [IF_NONE] = "none", @@ -1759,6 +1760,14 @@ void qmp_transaction(TransactionActionList *dev_list, Error **errp) TransactionActionList *dev_entry = dev_list; BlkTransactionState *state, *next; Error *local_err = NULL; + Error *blocker = NULL; + int ret; + + error_setg(&blocker, "Block device(s) are in use by a Block Transaction"); + ret = migrate_add_blocker(blocker, errp); + if (ret < 0) { + goto cleanup_mig; + } QSIMPLEQ_HEAD(snap_bdrv_states, BlkTransactionState) snap_bdrv_states; QSIMPLEQ_INIT(&snap_bdrv_states); @@ -1814,6 +1823,9 @@ exit: } g_free(state); } + cleanup_mig: + migrate_del_blocker(blocker); + error_free(blocker); }
Similarly to BlockJobs, prohibit migration at least during the synchronous phase of a transaction. In particular, this guards internal and external snapshots, which are implemented via transaction actions through blockdev_do_action. Signed-off-by: John Snow <jsnow@redhat.com> --- blockdev.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)