Commit 53f1c879 authored by Vladimir Sementsov-Ogievskiy's avatar Vladimir Sementsov-Ogievskiy Committed by Jeff Cody
Browse files

backup: use copy_bitmap in incremental backup 



We can use copy_bitmap instead of sync_bitmap. copy_bitmap is
initialized from sync_bitmap and it is more informative: we will not try
to process data, that is already in progress (by write notifier).

Signed-off-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: default avatarJohn Snow <jsnow@redhat.com>
Reviewed-by: default avatarJeff Cody <jcody@redhat.com>
Message-id: 20171012135313.227864-6-vsementsov@virtuozzo.com
Signed-off-by: default avatarJeff Cody <jcody@redhat.com>
parent 085bd08e

block/backup.c

+17 −38
Original line number Diff line number Diff line
@@ -362,49 +362,28 @@ static bool coroutine_fn yield_and_check(BackupBlockJob *job) 


static int coroutine_fn backup_run_incremental(BackupBlockJob *job)

{

    int ret;

    bool error_is_read;

    int ret = 0;

    int clusters_per_iter;

    uint32_t granularity;

    int64_t offset;

    int64_t cluster;

    int64_t end;

    BdrvDirtyBitmapIter *dbi;

    HBitmapIter hbi;



    granularity = bdrv_dirty_bitmap_granularity(job->sync_bitmap);

    clusters_per_iter = MAX((granularity / job->cluster_size), 1);

    dbi = bdrv_dirty_iter_new(job->sync_bitmap);



    /* Find the next dirty sector(s) */

    while ((offset = bdrv_dirty_iter_next(dbi)) >= 0) {

        cluster = offset / job->cluster_size;



        for (end = cluster + clusters_per_iter; cluster < end; cluster++) {

    hbitmap_iter_init(&hbi, job->copy_bitmap, 0);

    while ((cluster = hbitmap_iter_next(&hbi)) != -1) {

        do {

            if (yield_and_check(job)) {

                    goto out;

                return 0;

            }

            ret = backup_do_cow(job, cluster * job->cluster_size,

                                    job->cluster_size, &error_is_read,

                                    false);

                if ((ret < 0) &&

                    backup_error_action(job, error_is_read, -ret) ==

                    BLOCK_ERROR_ACTION_REPORT) {

                    goto out;

                                job->cluster_size, &error_is_read, false);

            if (ret < 0 && backup_error_action(job, error_is_read, -ret) ==

                           BLOCK_ERROR_ACTION_REPORT)

            {

                return ret;

            }

        } while (ret < 0);

    }



        /* If the bitmap granularity is smaller than the backup granularity,

         * we need to advance the iterator pointer to the next cluster. */

        if (granularity < job->cluster_size) {

            bdrv_set_dirty_iter(dbi, cluster * job->cluster_size);

        }

    }



out:

    bdrv_dirty_iter_free(dbi);

    return ret;

    return 0;

}



/* init copy_bitmap from sync_bitmap */