diff options
| -rw-r--r-- | block/dirty-bitmap.c | 6 | ||||
| -rw-r--r-- | include/block/dirty-bitmap.h | 2 | ||||
| -rw-r--r-- | include/qemu/hbitmap.h | 16 | ||||
| -rw-r--r-- | util/hbitmap.c | 39 |
4 files changed, 63 insertions, 0 deletions
diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c index b162f4ac22..c1518373f9 100644 --- a/block/dirty-bitmap.c +++ b/block/dirty-bitmap.c @@ -787,6 +787,12 @@ int64_t bdrv_dirty_bitmap_next_zero(BdrvDirtyBitmap *bitmap, uint64_t offset, return hbitmap_next_zero(bitmap->bitmap, offset, bytes); } +bool bdrv_dirty_bitmap_next_dirty_area(BdrvDirtyBitmap *bitmap, + uint64_t *offset, uint64_t *bytes) +{ + return hbitmap_next_dirty_area(bitmap->bitmap, offset, bytes); +} + void bdrv_merge_dirty_bitmap(BdrvDirtyBitmap *dest, const BdrvDirtyBitmap *src, HBitmap **backup, Error **errp) { diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h index 102ccdda32..4ef00ca6ba 100644 --- a/include/block/dirty-bitmap.h +++ b/include/block/dirty-bitmap.h @@ -101,6 +101,8 @@ BdrvDirtyBitmap *bdrv_dirty_bitmap_next(BlockDriverState *bs, char *bdrv_dirty_bitmap_sha256(const BdrvDirtyBitmap *bitmap, Error **errp); int64_t bdrv_dirty_bitmap_next_zero(BdrvDirtyBitmap *bitmap, uint64_t offset, uint64_t bytes); +bool bdrv_dirty_bitmap_next_dirty_area(BdrvDirtyBitmap *bitmap, + uint64_t *offset, uint64_t *bytes); BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap_locked(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, Error **errp); diff --git a/include/qemu/hbitmap.h b/include/qemu/hbitmap.h index 135975530f..097dce31ee 100644 --- a/include/qemu/hbitmap.h +++ b/include/qemu/hbitmap.h @@ -311,6 +311,22 @@ unsigned long hbitmap_iter_skip_words(HBitmapIter *hbi); */ int64_t hbitmap_next_zero(const HBitmap *hb, uint64_t start, uint64_t count); +/* hbitmap_next_dirty_area: + * @hb: The HBitmap to operate on + * @start: in-out parameter. + * in: the offset to start from + * out: (if area found) start of found area + * @count: in-out parameter. + * in: length of requested region + * out: length of found area + * + * If dirty area found within [@start, @start + @count), returns true and sets + * @offset and @bytes appropriately. Otherwise returns false and leaves @offset + * and @bytes unchanged. + */ +bool hbitmap_next_dirty_area(const HBitmap *hb, uint64_t *start, + uint64_t *count); + /* hbitmap_create_meta: * Create a "meta" hbitmap to track dirtiness of the bits in this HBitmap. * The caller owns the created bitmap and must call hbitmap_free_meta(hb) to diff --git a/util/hbitmap.c b/util/hbitmap.c index 09b3719e44..fa356522c4 100644 --- a/util/hbitmap.c +++ b/util/hbitmap.c @@ -246,6 +246,45 @@ int64_t hbitmap_next_zero(const HBitmap *hb, uint64_t start, uint64_t count) return res; } +bool hbitmap_next_dirty_area(const HBitmap *hb, uint64_t *start, + uint64_t *count) +{ + HBitmapIter hbi; + int64_t firt_dirty_off, area_end; + uint32_t granularity = 1UL << hb->granularity; + uint64_t end; + + if (*start >= hb->orig_size || *count == 0) { + return false; + } + + end = *count > hb->orig_size - *start ? hb->orig_size : *start + *count; + + hbitmap_iter_init(&hbi, hb, *start); + firt_dirty_off = hbitmap_iter_next(&hbi, false); + + if (firt_dirty_off < 0 || firt_dirty_off >= end) { + return false; + } + + if (firt_dirty_off + granularity >= end) { + area_end = end; + } else { + area_end = hbitmap_next_zero(hb, firt_dirty_off + granularity, + end - firt_dirty_off - granularity); + if (area_end < 0) { + area_end = end; + } + } + + if (firt_dirty_off > *start) { + *start = firt_dirty_off; + } + *count = area_end - *start; + + return true; +} + bool hbitmap_empty(const HBitmap *hb) { return hb->count == 0; |