Commit 7cb14481 authored by Denis V. Lunev's avatar Denis V. Lunev Committed by Juan Quintela
Browse files

migration: implement bdrv_all_find_vmstate_bs helper 



The patch also ensures proper locking for the operation.

Signed-off-by: default avatarDenis V. Lunev <den@openvz.org>
Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: default avatarFam Zheng <famz@redhat.com>
Reviewed-by: default avatarJuan Quintela <quintela@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Tested-by: default avatarGreg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: default avatarJuan Quintela <quintela@redhat.com>
parent 0b461605

block/snapshot.c

+15 −0
Original line number Diff line number Diff line
@@ -469,3 +469,18 @@ int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn, 
    *first_bad_bs = bs;

    return err;

}



BlockDriverState *bdrv_all_find_vmstate_bs(void)

{

    bool not_found = true;

    BlockDriverState *bs = NULL;



    while (not_found && (bs = bdrv_next(bs))) {

        AioContext *ctx = bdrv_get_aio_context(bs);



        aio_context_acquire(ctx);

        not_found = !bdrv_can_snapshot(bs);

        aio_context_release(ctx);

    }

    return bs;

}

include/block/snapshot.h

+2 −0
Original line number Diff line number Diff line
@@ -91,4 +91,6 @@ int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn, 
                             uint64_t vm_state_size,

                             BlockDriverState **first_bad_bs);



BlockDriverState *bdrv_all_find_vmstate_bs(void);



#endif

migration/savevm.c

+4 −15
Original line number Diff line number Diff line
@@ -1905,17 +1905,6 @@ int qemu_loadvm_state(QEMUFile *f) 
    return ret;

}



static BlockDriverState *find_vmstate_bs(void)

{

    BlockDriverState *bs = NULL;

    while ((bs = bdrv_next(bs))) {

        if (bdrv_can_snapshot(bs)) {

            return bs;

        }

    }

    return NULL;

}



void hmp_savevm(Monitor *mon, const QDict *qdict)

{

    BlockDriverState *bs, *bs1;
@@ -1944,8 +1933,8 @@ void hmp_savevm(Monitor *mon, const QDict *qdict) 
        return;

    }



    bs = find_vmstate_bs();

    if (!bs) {

    bs = bdrv_all_find_vmstate_bs();

    if (bs == NULL) {

        monitor_printf(mon, "No block device can accept snapshots\n");

        return;

    }
@@ -2054,7 +2043,7 @@ int load_vmstate(const char *name) 
        return ret;

    }



    bs_vm_state = find_vmstate_bs();

    bs_vm_state = bdrv_all_find_vmstate_bs();

    if (!bs_vm_state) {

        error_report("No block device supports snapshots");

        return -ENOTSUP;
@@ -2123,7 +2112,7 @@ void hmp_info_snapshots(Monitor *mon, const QDict *qdict) 
    int total;

    int *available_snapshots;



    bs = find_vmstate_bs();

    bs = bdrv_all_find_vmstate_bs();

    if (!bs) {

        monitor_printf(mon, "No available block device supports snapshots\n");

        return;