Re: [Qemu-devel] [PATCH v4 2/3] qcow2: handle reopening bitmaps on bdrv_invalidate_cache DROP IT

[Vladimir Sementsov-Ogievskiy]

Oh, sorry, just drop it.
(the only difference is commit message subject)

20.03.2018 20:05, Vladimir Sementsov-Ogievskiy wrote:
> On reopen with existing bitmaps, instead of loading bitmaps, lets
> reopen them if needed. This also fixes bitmaps migration through
> shared storage.
> Consider the case. Persistent bitmaps are stored on bdrv_inactivate.
> Then, on destination process_incoming_migration_bh() calls
> bdrv_invalidate_cache_all() which leads to
> qcow2_load_autoloading_dirty_bitmaps() which fails if bitmaps are
> already loaded on destination start.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <address@hidden>
> ---
>   block/qcow2.c | 17 ++++++++++++++++-
>   1 file changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/block/qcow2.c b/block/qcow2.c
> index 7472af6931..d2d129a2e6 100644
> --- a/block/qcow2.c
> +++ b/block/qcow2.c
> @@ -1480,7 +1480,22 @@ static int coroutine_fn qcow2_do_open(BlockDriverState 
> *bs, QDict *options,
>           s->autoclear_features &= QCOW2_AUTOCLEAR_MASK;
>       }
>   
> -    if (qcow2_load_dirty_bitmaps(bs, &local_err)) {
> +    if (bdrv_dirty_bitmap_next(bs, NULL)) {
> +        /* It's some kind of reopen with already existing dirty bitmaps. There
> +         * are no known cases where we need loading bitmaps in such situation,
> +         * so it's safer don't load them.
> +         *
> +         * Moreover, if we have some readonly bitmaps and we are reopening for
> +         * rw we should reopen bitmaps correspondingly.
> +         */
> +        if (bdrv_has_readonly_bitmaps(bs) &&
> +            !bdrv_is_read_only(bs) && !(bdrv_get_flags(bs) & BDRV_O_INACTIVE))
> +        {
> +            bool header_updated = false;
> +            qcow2_reopen_bitmaps_rw_hint(bs, &header_updated, &local_err);
> +            update_header = update_header && !header_updated;
> +        }
> +    } else if (qcow2_load_dirty_bitmaps(bs, &local_err)) {
>           update_header = false;
>       }
>       if (local_err != NULL) {


--
Best regards,
Vladimir