Commit a410a7f1 authored by Vladimir Sementsov-Ogievskiy's avatar Vladimir Sementsov-Ogievskiy Committed by Kevin Wolf
Browse files

backup: allow target without .bdrv_get_info 



Currently backup to nbd target is broken, as nbd doesn't have
.bdrv_get_info realization.

Signed-off-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: default avatarEric Blake <eblake@redhat.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent dd4d2578

block/backup.c

+11 −1
Original line number Diff line number Diff line
@@ -24,6 +24,7 @@ 
#include "qemu/cutils.h"

#include "sysemu/block-backend.h"

#include "qemu/bitmap.h"

#include "qemu/error-report.h"



#define BACKUP_CLUSTER_SIZE_DEFAULT (1 << 16)

#define SLICE_TIME 100000000ULL /* ns */
@@ -648,7 +649,16 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, 
     * backup cluster size is smaller than the target cluster size. Even for

     * targets with a backing file, try to avoid COW if possible. */

    ret = bdrv_get_info(target, &bdi);

    if (ret < 0 && !target->backing) {

    if (ret == -ENOTSUP && !target->backing) {

        /* Cluster size is not defined */

        error_report("WARNING: The target block device doesn't provide "

                     "information about the block size and it doesn't have a "

                     "backing file. The default block size of %u bytes is "

                     "used. If the actual block size of the target exceeds "

                     "this default, the backup may be unusable",

                     BACKUP_CLUSTER_SIZE_DEFAULT);

        job->cluster_size = BACKUP_CLUSTER_SIZE_DEFAULT;

    } else if (ret < 0 && !target->backing) {

        error_setg_errno(errp, -ret,

            "Couldn't determine the cluster size of the target image, "

            "which has no backing file");