| 1 | /* |
| 2 | * QEMU Hyper-V Dynamic Memory Protocol driver |
| 3 | * |
| 4 | * Copyright (C) 2020-2023 Oracle and/or its affiliates. |
| 5 | * |
| 6 | * This work is licensed under the terms of the GNU GPL, version 2 or later. |
| 7 | * See the COPYING file in the top-level directory. |
| 8 | */ |
| 9 | |
| 10 | #ifndef HW_HYPERV_HV_BALLOON_INTERNAL_H |
| 11 | #define HW_HYPERV_HV_BALLOON_INTERNAL_H |
| 12 | |
| 13 | |
| 14 | #define HV_BALLOON_PFN_SHIFT 12 |
| 15 | #define HV_BALLOON_PAGE_SIZE (1 << HV_BALLOON_PFN_SHIFT) |
| 16 | |
| 17 | #define SUM_OVERFLOW_U64(in1, in2) ((in1) > UINT64_MAX - (in2)) |
| 18 | #define SUM_SATURATE_U64(in1, in2) \ |
| 19 | ({ \ |
| 20 | uint64_t _in1 = (in1), _in2 = (in2); \ |
| 21 | uint64_t _result; \ |
| 22 | \ |
| 23 | if (!SUM_OVERFLOW_U64(_in1, _in2)) { \ |
| 24 | _result = _in1 + _in2; \ |
| 25 | } else { \ |
| 26 | _result = UINT64_MAX; \ |
| 27 | } \ |
| 28 | \ |
| 29 | _result; \ |
| 30 | }) |
| 31 | |
| 32 | #endif |