diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c index f82478c02a..a8c7e1d190 100644 --- a/block/qcow2-bitmap.c +++ b/block/qcow2-bitmap.c @@ -1388,3 +1388,54 @@ int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp) return 0; } + +bool qcow2_can_store_new_dirty_bitmap(BlockDriverState *bs, + const char *name, + uint32_t granularity, + Error **errp) +{ + BDRVQcow2State *s = bs->opaque; + bool found; + Qcow2BitmapList *bm_list; + + if (check_constraints_on_bitmap(bs, name, granularity, errp) != 0) { + goto fail; + } + + if (s->nb_bitmaps == 0) { + return true; + } + + if (s->nb_bitmaps >= QCOW2_MAX_BITMAPS) { + error_setg(errp, + "Maximum number of persistent bitmaps is already reached"); + goto fail; + } + + if (s->bitmap_directory_size + calc_dir_entry_size(strlen(name), 0) > + QCOW2_MAX_BITMAP_DIRECTORY_SIZE) + { + error_setg(errp, "Not enough space in the bitmap directory"); + goto fail; + } + + bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, + s->bitmap_directory_size, errp); + if (bm_list == NULL) { + goto fail; + } + + found = find_bitmap_by_name(bm_list, name); + bitmap_list_free(bm_list); + if (found) { + error_setg(errp, "Bitmap with the same name is already stored"); + goto fail; + } + + return true; + +fail: + error_prepend(errp, "Can't make bitmap '%s' persistent in '%s': ", + name, bdrv_get_device_or_node_name(bs)); + return false; +} diff --git a/block/qcow2.c b/block/qcow2.c index 1a31f1d360..d7046a3a48 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -3989,6 +3989,7 @@ BlockDriver bdrv_qcow2 = { .bdrv_attach_aio_context = qcow2_attach_aio_context, .bdrv_reopen_bitmaps_rw = qcow2_reopen_bitmaps_rw, + .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 1f80b5d8d4..084a298ebc 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -649,5 +649,9 @@ bool qcow2_load_autoloading_dirty_bitmaps(BlockDriverState *bs, Error **errp); int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp); void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error **errp); int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp); +bool qcow2_can_store_new_dirty_bitmap(BlockDriverState *bs, + const char *name, + uint32_t granularity, + Error **errp); #endif