Commit 592203e7 authored by John Snow's avatar John Snow
Browse files

migration/dirty-bitmaps: change bitmap enumeration method 



Shift from looking at every root BDS to *every* BDS. This will migrate
bitmaps that are attached to blockdev created nodes instead of just ones
attached to emulated storage devices.

Note that this will not migrate anonymous or internal-use bitmaps, as
those are defined as having no name.

This will also fix the Coverity issues Peter Maydell has been asking
about for the past several releases, as well as fixing a real bug.

Reported-by: default avatarPeter Maydell <peter.maydell@linaro.org>
Reported-by: Coverity 😅


Reported-by: default avataraihua liang <aliang@redhat.com>
Reviewed-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: default avatarJohn Snow <jsnow@redhat.com>
Message-id: 20190514201926.10407-1-jsnow@redhat.com
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1652490


Fixes: Coverity CID 1390625
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: default avatarJohn Snow <jsnow@redhat.com>
parent 8c1ecb59

migration/block-dirty-bitmap.c

+4 −10
Original line number Diff line number Diff line
@@ -273,7 +273,6 @@ static int init_dirty_bitmap_migration(void) 
    BlockDriverState *bs;

    BdrvDirtyBitmap *bitmap;

    DirtyBitmapMigBitmapState *dbms;

    BdrvNextIterator it;

    Error *local_err = NULL;



    dirty_bitmap_mig_state.bulk_completed = false;
@@ -281,13 +280,8 @@ static int init_dirty_bitmap_migration(void) 
    dirty_bitmap_mig_state.prev_bitmap = NULL;

    dirty_bitmap_mig_state.no_bitmaps = false;



    for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {

        const char *drive_name = bdrv_get_device_or_node_name(bs);



        /* skip automatically inserted nodes */

        while (bs && bs->drv && bs->implicit) {

            bs = backing_bs(bs);

        }

    for (bs = bdrv_next_all_states(NULL); bs; bs = bdrv_next_all_states(bs)) {

        const char *name = bdrv_get_device_or_node_name(bs);



        for (bitmap = bdrv_dirty_bitmap_next(bs, NULL); bitmap;

             bitmap = bdrv_dirty_bitmap_next(bs, bitmap))
@@ -296,7 +290,7 @@ static int init_dirty_bitmap_migration(void) 
                continue;

            }



            if (drive_name == NULL) {

            if (!name || strcmp(name, "") == 0) {

                error_report("Found bitmap '%s' in unnamed node %p. It can't "

                             "be migrated", bdrv_dirty_bitmap_name(bitmap), bs);

                goto fail;
@@ -313,7 +307,7 @@ static int init_dirty_bitmap_migration(void) 


            dbms = g_new0(DirtyBitmapMigBitmapState, 1);

            dbms->bs = bs;

            dbms->node_name = drive_name;

            dbms->node_name = name;

            dbms->bitmap = bitmap;

            dbms->total_sectors = bdrv_nb_sectors(bs);

            dbms->sectors_per_chunk = CHUNK_SIZE * 8 *