diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c index 1b14c8eb26..063793e316 100644 --- a/block/dirty-bitmap.c +++ b/block/dirty-bitmap.c @@ -873,9 +873,11 @@ int64_t bdrv_dirty_bitmap_next_zero(BdrvDirtyBitmap *bitmap, int64_t offset, } bool bdrv_dirty_bitmap_next_dirty_area(BdrvDirtyBitmap *bitmap, - int64_t *offset, int64_t *bytes) + int64_t start, int64_t end, int64_t max_dirty_count, + int64_t *dirty_start, int64_t *dirty_count) { - return hbitmap_next_dirty_area(bitmap->bitmap, offset, bytes); + return hbitmap_next_dirty_area(bitmap->bitmap, start, end, max_dirty_count, + dirty_start, dirty_count); } /** diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h index b1f0de12db..8a10029418 100644 --- a/include/block/dirty-bitmap.h +++ b/include/block/dirty-bitmap.h @@ -110,7 +110,8 @@ int64_t bdrv_dirty_bitmap_next_dirty(BdrvDirtyBitmap *bitmap, int64_t offset, int64_t bdrv_dirty_bitmap_next_zero(BdrvDirtyBitmap *bitmap, int64_t offset, int64_t bytes); bool bdrv_dirty_bitmap_next_dirty_area(BdrvDirtyBitmap *bitmap, - int64_t *offset, int64_t *bytes); + int64_t start, int64_t end, int64_t max_dirty_count, + int64_t *dirty_start, int64_t *dirty_count); BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap_locked(BdrvDirtyBitmap *bitmap, Error **errp); diff --git a/include/qemu/hbitmap.h b/include/qemu/hbitmap.h index 6e9ae51ed3..5e71b6d6f7 100644 --- a/include/qemu/hbitmap.h +++ b/include/qemu/hbitmap.h @@ -324,18 +324,21 @@ int64_t hbitmap_next_zero(const HBitmap *hb, int64_t start, int64_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 + * @start: the offset to start from + * @end: end of requested area + * @max_dirty_count: limit for out parameter dirty_count + * @dirty_start: on success: start of found area + * @dirty_count: on success: 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. + * If dirty area found within [@start, @end), returns true and sets + * @dirty_start and @dirty_count appropriately. @dirty_count will not exceed + * @max_dirty_count. + * If dirty area was not found, returns false and leaves @dirty_start and + * @dirty_count unchanged. */ -bool hbitmap_next_dirty_area(const HBitmap *hb, int64_t *start, int64_t *count); +bool hbitmap_next_dirty_area(const HBitmap *hb, int64_t start, int64_t end, + int64_t max_dirty_count, + int64_t *dirty_start, int64_t *dirty_count); /** * hbitmap_iter_next: diff --git a/tests/test-hbitmap.c b/tests/test-hbitmap.c index 8905b8a351..b6726cf76b 100644 --- a/tests/test-hbitmap.c +++ b/tests/test-hbitmap.c @@ -920,18 +920,19 @@ static void test_hbitmap_next_x_after_truncate(TestHBitmapData *data, test_hbitmap_next_x_check(data, 0); } -static void test_hbitmap_next_dirty_area_check(TestHBitmapData *data, - int64_t offset, - int64_t count) +static void test_hbitmap_next_dirty_area_check_limited(TestHBitmapData *data, + int64_t offset, + int64_t count, + int64_t max_dirty) { int64_t off1, off2; int64_t len1 = 0, len2; bool ret1, ret2; int64_t end; - off1 = offset; - len1 = count; - ret1 = hbitmap_next_dirty_area(data->hb, &off1, &len1); + ret1 = hbitmap_next_dirty_area(data->hb, + offset, count == INT64_MAX ? INT64_MAX : offset + count, max_dirty, + &off1, &len1); end = offset > data->size || data->size - offset < count ? data->size : offset + count; @@ -940,21 +941,25 @@ static void test_hbitmap_next_dirty_area_check(TestHBitmapData *data, ; } - for (len2 = 1; off2 + len2 < end && hbitmap_get(data->hb, off2 + len2); - len2++) { + for (len2 = 1; (off2 + len2 < end && len2 < max_dirty && + hbitmap_get(data->hb, off2 + len2)); len2++) + { ; } ret2 = off2 < end; - if (!ret2) { - /* leave unchanged */ - off2 = offset; - len2 = count; - } - g_assert_cmpint(ret1, ==, ret2); - g_assert_cmpint(off1, ==, off2); - g_assert_cmpint(len1, ==, len2); + + if (ret2) { + g_assert_cmpint(off1, ==, off2); + g_assert_cmpint(len1, ==, len2); + } +} + +static void test_hbitmap_next_dirty_area_check(TestHBitmapData *data, + int64_t offset, int64_t count) +{ + test_hbitmap_next_dirty_area_check_limited(data, offset, count, INT64_MAX); } static void test_hbitmap_next_dirty_area_do(TestHBitmapData *data, @@ -964,6 +969,7 @@ static void test_hbitmap_next_dirty_area_do(TestHBitmapData *data, test_hbitmap_next_dirty_area_check(data, 0, INT64_MAX); test_hbitmap_next_dirty_area_check(data, 0, 1); test_hbitmap_next_dirty_area_check(data, L3 - 1, 1); + test_hbitmap_next_dirty_area_check_limited(data, 0, INT64_MAX, 1); hbitmap_set(data->hb, L2, 1); test_hbitmap_next_dirty_area_check(data, 0, 1); @@ -976,6 +982,8 @@ static void test_hbitmap_next_dirty_area_do(TestHBitmapData *data, test_hbitmap_next_dirty_area_check(data, L2, INT64_MAX); test_hbitmap_next_dirty_area_check(data, L2, 1); test_hbitmap_next_dirty_area_check(data, L2 + 1, 1); + test_hbitmap_next_dirty_area_check_limited(data, 0, INT64_MAX, 1); + test_hbitmap_next_dirty_area_check_limited(data, L2 - 1, 2, 1); hbitmap_set(data->hb, L2 + 5, L1); test_hbitmap_next_dirty_area_check(data, 0, INT64_MAX); @@ -988,6 +996,8 @@ static void test_hbitmap_next_dirty_area_do(TestHBitmapData *data, test_hbitmap_next_dirty_area_check(data, L2 + L1, L1); test_hbitmap_next_dirty_area_check(data, L2, 0); test_hbitmap_next_dirty_area_check(data, L2 + 1, 0); + test_hbitmap_next_dirty_area_check_limited(data, L2 + 3, INT64_MAX, 3); + test_hbitmap_next_dirty_area_check_limited(data, L2 + 3, 7, 10); hbitmap_set(data->hb, L2 * 2, L3 - L2 * 2); test_hbitmap_next_dirty_area_check(data, 0, INT64_MAX); @@ -997,6 +1007,9 @@ static void test_hbitmap_next_dirty_area_do(TestHBitmapData *data, test_hbitmap_next_dirty_area_check(data, L2 + 5 + L1, 5); test_hbitmap_next_dirty_area_check(data, L2 * 2 - L1, L1 + 1); test_hbitmap_next_dirty_area_check(data, L2 * 2, L2); + test_hbitmap_next_dirty_area_check_limited(data, L2 * 2 + 1, INT64_MAX, 5); + test_hbitmap_next_dirty_area_check_limited(data, L2 * 2 + 1, 10, 5); + test_hbitmap_next_dirty_area_check_limited(data, L2 * 2 + 1, 2, 5); hbitmap_set(data->hb, 0, L3); test_hbitmap_next_dirty_area_check(data, 0, INT64_MAX); diff --git a/util/hbitmap.c b/util/hbitmap.c index 883ca48fa6..305b894a63 100644 --- a/util/hbitmap.c +++ b/util/hbitmap.c @@ -270,22 +270,33 @@ int64_t hbitmap_next_zero(const HBitmap *hb, int64_t start, int64_t count) return res; } -bool hbitmap_next_dirty_area(const HBitmap *hb, int64_t *start, int64_t *count) +bool hbitmap_next_dirty_area(const HBitmap *hb, int64_t start, int64_t end, + int64_t max_dirty_count, + int64_t *dirty_start, int64_t *dirty_count) { - int64_t area_start, area_end; + int64_t next_zero; - area_start = hbitmap_next_dirty(hb, *start, *count); - if (area_start < 0) { + assert(start >= 0 && end >= 0 && max_dirty_count > 0); + + end = MIN(end, hb->orig_size); + if (start >= end) { return false; } - area_end = hbitmap_next_zero(hb, area_start, *start + *count - area_start); - if (area_end < 0) { - area_end = MIN(hb->orig_size, *start + *count); + start = hbitmap_next_dirty(hb, start, end - start); + if (start < 0) { + return false; } - *start = area_start; - *count = area_end - area_start; + end = start + MIN(end - start, max_dirty_count); + + next_zero = hbitmap_next_zero(hb, start, end - start); + if (next_zero >= 0) { + end = next_zero; + } + + *dirty_start = start; + *dirty_count = end - start; return true; } @@ -841,16 +852,15 @@ bool hbitmap_can_merge(const HBitmap *a, const HBitmap *b) */ static void hbitmap_sparse_merge(HBitmap *dst, const HBitmap *src) { - int64_t offset = 0; - int64_t count = src->orig_size; + int64_t offset; + int64_t count; - while (hbitmap_next_dirty_area(src, &offset, &count)) { + for (offset = 0; + hbitmap_next_dirty_area(src, offset, src->orig_size, INT64_MAX, + &offset, &count); + offset += count) + { hbitmap_set(dst, offset, count); - offset += count; - if (offset >= src->orig_size) { - break; - } - count = src->orig_size - offset; } }