On 02/14/2017 11:59 AM, Vladimir Sementsov-Ogievskiy wrote:
> Realize .bdrv_can_store_new_dirty_bitmap interface.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
> block/qcow2-bitmap.c | 40 ++++++++++++++++++++++++++++++++++++++++
> block/qcow2.c | 1 +
> block/qcow2.h | 4 ++++
> 3 files changed, 45 insertions(+)
>
> diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c
> index b177a95..419d51e 100644
> --- a/block/qcow2-bitmap.c
> +++ b/block/qcow2-bitmap.c
> @@ -1182,3 +1182,43 @@ fail:
>
> bitmap_list_free(bm_list);
> }
> +
> +bool qcow2_can_store_new_dirty_bitmap(BlockDriverState *bs,
> + const char *name,
> + uint32_t granularity,
> + Error **errp)
> +{
> + BDRVQcow2State *s = bs->opaque;
> + const char *reason = NULL;
> + bool found;
> + Qcow2BitmapList *bm_list;
> +
> + if (check_constraints_on_bitmap(bs, name, granularity) != 0) {
> + reason = "it doesn't satisfy the constraints";
> + goto common_errp;
> + }
"the constraints" are still entirely opaque to the caller, it may not be
obvious that it's because of the name length.
(But maybe you fix this in patch 25.)
> +
> + if (s->nb_bitmaps == 0) {
> + return true;
> + }
> +
> + bm_list = bitmap_list_load(bs, s->bitmap_directory_offset,
> + s->bitmap_directory_size, errp);
> + if (bm_list == NULL) {
> + return false;
> + }
Another opportunity for caching the bm_list.
> +
> + found = find_bitmap_by_name(bm_list, name);
> + bitmap_list_free(bm_list);
> + if (found) {
> + reason = "bitmap with the same name is already stored";
> + goto common_errp;
> + }
> +
> + return true;
> +
> +common_errp:
> + error_setg(errp, "Can't make bitmap '%s' persistent in '%s', as %s.",
> + name, bdrv_get_device_or_node_name(bs), reason);
> + return false;
> +}
We don't check total numbers of bitmaps here? (I'll keep reading ahead
in the series.)
> diff --git a/block/qcow2.c b/block/qcow2.c
> index d0e41bf..6e1fe53 100644
> --- a/block/qcow2.c
> +++ b/block/qcow2.c
> @@ -3541,6 +3541,7 @@ BlockDriver bdrv_qcow2 = {
>
> .bdrv_load_autoloading_dirty_bitmaps = qcow2_load_autoloading_dirty_bitmaps,
> .bdrv_store_persistent_dirty_bitmaps = qcow2_store_persistent_dirty_bitmaps,
> + .bdrv_can_store_new_dirty_bitmap = qcow2_can_store_new_dirty_bitmap,
> };
>
> static void bdrv_qcow2_init(void)
> diff --git a/block/qcow2.h b/block/qcow2.h
> index d9a7643..749710d 100644
> --- a/block/qcow2.h
> +++ b/block/qcow2.h
> @@ -616,5 +616,9 @@ void qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table);
> /* qcow2-bitmap.c functions */
> void qcow2_load_autoloading_dirty_bitmaps(BlockDriverState *bs, Error **errp);
> void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error **errp);
> +bool qcow2_can_store_new_dirty_bitmap(BlockDriverState *bs,
> + const char *name,
> + uint32_t granularity,
> + Error **errp);
>
> #endif
>
Benefit of the doubt:
Reviewed-by: John Snow <jsnow@redhat.com>