diff options
| -rw-r--r-- | block/dirty-bitmap.c | 52 | ||||
| -rw-r--r-- | include/block/dirty-bitmap.h | 9 |
2 files changed, 61 insertions, 0 deletions
diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c index c572dfa941..9c6febbcb7 100644 --- a/block/dirty-bitmap.c +++ b/block/dirty-bitmap.c @@ -38,6 +38,7 @@ */ struct BdrvDirtyBitmap { HBitmap *bitmap; /* Dirty sector bitmap implementation */ + HBitmap *meta; /* Meta dirty bitmap */ BdrvDirtyBitmap *successor; /* Anonymous child; implies frozen status */ char *name; /* Optional non-empty unique ID */ int64_t size; /* Size of the bitmap (Number of sectors) */ @@ -103,6 +104,56 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, return bitmap; } +/* bdrv_create_meta_dirty_bitmap + * + * Create a meta dirty bitmap that tracks the changes of bits in @bitmap. I.e. + * when a dirty status bit in @bitmap is changed (either from reset to set or + * the other way around), its respective meta dirty bitmap bit will be marked + * dirty as well. + * + * @bitmap: the block dirty bitmap for which to create a meta dirty bitmap. + * @chunk_size: how many bytes of bitmap data does each bit in the meta bitmap + * track. + */ +void bdrv_create_meta_dirty_bitmap(BdrvDirtyBitmap *bitmap, + int chunk_size) +{ + assert(!bitmap->meta); + bitmap->meta = hbitmap_create_meta(bitmap->bitmap, + chunk_size * BITS_PER_BYTE); +} + +void bdrv_release_meta_dirty_bitmap(BdrvDirtyBitmap *bitmap) +{ + assert(bitmap->meta); + hbitmap_free_meta(bitmap->bitmap); + bitmap->meta = NULL; +} + +int bdrv_dirty_bitmap_get_meta(BlockDriverState *bs, + BdrvDirtyBitmap *bitmap, int64_t sector, + int nb_sectors) +{ + uint64_t i; + int sectors_per_bit = 1 << hbitmap_granularity(bitmap->meta); + + /* To optimize: we can make hbitmap to internally check the range in a + * coarse level, or at least do it word by word. */ + for (i = sector; i < sector + nb_sectors; i += sectors_per_bit) { + if (hbitmap_get(bitmap->meta, i)) { + return true; + } + } + return false; +} + +void bdrv_dirty_bitmap_reset_meta(BlockDriverState *bs, + BdrvDirtyBitmap *bitmap, int64_t sector, + int nb_sectors) +{ + hbitmap_reset(bitmap->meta, sector, nb_sectors); +} + bool bdrv_dirty_bitmap_frozen(BdrvDirtyBitmap *bitmap) { return bitmap->successor; @@ -233,6 +284,7 @@ static void bdrv_do_release_matching_dirty_bitmap(BlockDriverState *bs, if ((!bitmap || bm == bitmap) && (!only_named || bm->name)) { 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); diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h index 0ef927d6ce..69c500ba2f 100644 --- a/include/block/dirty-bitmap.h +++ b/include/block/dirty-bitmap.h @@ -8,6 +8,9 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, uint32_t granularity, const char *name, Error **errp); +void bdrv_create_meta_dirty_bitmap(BdrvDirtyBitmap *bitmap, + int chunk_size); +void bdrv_release_meta_dirty_bitmap(BdrvDirtyBitmap *bitmap); int bdrv_dirty_bitmap_create_successor(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, Error **errp); @@ -36,6 +39,12 @@ void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap, int64_t cur_sector, int64_t nr_sectors); void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap, int64_t cur_sector, int64_t nr_sectors); +int bdrv_dirty_bitmap_get_meta(BlockDriverState *bs, + BdrvDirtyBitmap *bitmap, int64_t sector, + int nb_sectors); +void bdrv_dirty_bitmap_reset_meta(BlockDriverState *bs, + BdrvDirtyBitmap *bitmap, int64_t sector, + int nb_sectors); BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap, uint64_t first_sector); void bdrv_dirty_iter_free(BdrvDirtyBitmapIter *iter); |