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
33