Commit 604ab74b authored by Vladimir Sementsov-Ogievskiy's avatar Vladimir Sementsov-Ogievskiy Committed by John Snow
Browse files

block/dirty-bitmap: fix locking in bdrv_reclaim_dirty_bitmap 



Like other setters here these functions should take a lock.

Signed-off-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: default avatarFam Zheng <famz@redhat.com>
Reviewed-by: default avatarJohn Snow <jsnow@redhat.com>
Message-id: 20180207155837.92351-3-vsementsov@virtuozzo.com
Signed-off-by: default avatarJohn Snow <jsnow@redhat.com>
parent e73a265e

block/dirty-bitmap.c

+53 −32
Original line number Diff line number Diff line
@@ -242,6 +242,51 @@ void bdrv_dirty_bitmap_enable_successor(BdrvDirtyBitmap *bitmap) 
    qemu_mutex_unlock(bitmap->mutex);

}



/* Called within bdrv_dirty_bitmap_lock..unlock */

static void bdrv_do_release_matching_dirty_bitmap_locked(

    BlockDriverState *bs, BdrvDirtyBitmap *bitmap,

    bool (*cond)(BdrvDirtyBitmap *bitmap))

{

    BdrvDirtyBitmap *bm, *next;



    QLIST_FOREACH_SAFE(bm, &bs->dirty_bitmaps, list, next) {

        if ((!bitmap || bm == bitmap) && (!cond || cond(bm))) {

            assert(!bm->active_iterators);

            assert(!bdrv_dirty_bitmap_frozen(bm));

            assert(!bm->meta);

            QLIST_REMOVE(bm, list);

            hbitmap_free(bm->bitmap);

            g_free(bm->name);

            g_free(bm);



            if (bitmap) {

                return;

            }

        }

    }



    if (bitmap) {

        abort();

    }

}



/* Called with BQL taken.  */

static void bdrv_do_release_matching_dirty_bitmap(

    BlockDriverState *bs, BdrvDirtyBitmap *bitmap,

    bool (*cond)(BdrvDirtyBitmap *bitmap))

{

    bdrv_dirty_bitmaps_lock(bs);

    bdrv_do_release_matching_dirty_bitmap_locked(bs, bitmap, cond);

    bdrv_dirty_bitmaps_unlock(bs);

}



/* Called within bdrv_dirty_bitmap_lock..unlock */

static void bdrv_release_dirty_bitmap_locked(BlockDriverState *bs,

                                             BdrvDirtyBitmap *bitmap)

{

    bdrv_do_release_matching_dirty_bitmap_locked(bs, bitmap, NULL);

}



/**

 * For a bitmap with a successor, yield our name to the successor,

 * delete the old bitmap, and return a handle to the new bitmap.
@@ -281,7 +326,11 @@ BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs, 
                                           BdrvDirtyBitmap *parent,

                                           Error **errp)

{

    BdrvDirtyBitmap *successor = parent->successor;

    BdrvDirtyBitmap *successor;



    qemu_mutex_lock(parent->mutex);



    successor = parent->successor;



    if (!successor) {

        error_setg(errp, "Cannot reclaim a successor when none is present");
@@ -292,9 +341,11 @@ BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs, 
        error_setg(errp, "Merging of parent and successor bitmap failed");

        return NULL;

    }

    bdrv_release_dirty_bitmap(bs, successor);

    bdrv_release_dirty_bitmap_locked(bs, successor);

    parent->successor = NULL;



    qemu_mutex_unlock(parent->mutex);



    return parent;

}
@@ -321,36 +372,6 @@ static bool bdrv_dirty_bitmap_has_name(BdrvDirtyBitmap *bitmap) 
    return !!bdrv_dirty_bitmap_name(bitmap);

}



/* Called with BQL taken.  */

static void bdrv_do_release_matching_dirty_bitmap(

    BlockDriverState *bs, BdrvDirtyBitmap *bitmap,

    bool (*cond)(BdrvDirtyBitmap *bitmap))

{

    BdrvDirtyBitmap *bm, *next;

    bdrv_dirty_bitmaps_lock(bs);

    QLIST_FOREACH_SAFE(bm, &bs->dirty_bitmaps, list, next) {

        if ((!bitmap || bm == bitmap) && (!cond || cond(bm))) {

            assert(!bm->active_iterators);

            assert(!bdrv_dirty_bitmap_frozen(bm));

            assert(!bm->meta);

            QLIST_REMOVE(bm, list);

            hbitmap_free(bm->bitmap);

            g_free(bm->name);

            g_free(bm);



            if (bitmap) {

                goto out;

            }

        }

    }

    if (bitmap) {

        abort();

    }



out:

    bdrv_dirty_bitmaps_unlock(bs);

}



/* Called with BQL taken.  */

void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)

{