xref: /kvmtool/include/kvm/util.h (revision fc184a682a2164c156655ec18bc4a18bb638f644)
1 #include <linux/stringify.h>
2 
3 #ifndef KVM__UTIL_H
4 #define KVM__UTIL_H
5 
6 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
7 
8 /*
9  * Some bits are stolen from perf tool :)
10  */
11 
12 #include <unistd.h>
13 #include <stdio.h>
14 #include <stddef.h>
15 #include <stdlib.h>
16 #include <stdarg.h>
17 #include <string.h>
18 #include <stdbool.h>
19 #include <signal.h>
20 #include <errno.h>
21 #include <limits.h>
22 #include <sys/param.h>
23 #include <sys/types.h>
24 #include <linux/types.h>
25 
26 #ifdef __GNUC__
27 #define NORETURN __attribute__((__noreturn__))
28 #else
29 #define NORETURN
30 #ifndef __attribute__
31 #define __attribute__(x)
32 #endif
33 #endif
34 
35 extern bool do_debug_print;
36 
37 #define PROT_RW (PROT_READ|PROT_WRITE)
38 #define MAP_ANON_NORESERVE (MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE)
39 
40 extern void die(const char *err, ...) NORETURN __attribute__((format (printf, 1, 2)));
41 extern void die_perror(const char *s) NORETURN;
42 extern void pr_err(const char *err, ...) __attribute__((format (printf, 1, 2)));
43 extern void pr_warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
44 extern void pr_info(const char *err, ...) __attribute__((format (printf, 1, 2)));
45 extern void __pr_debug(const char *debug, ...) __attribute__((format (printf, 1, 2)));
46 extern void set_die_routine(void (*routine)(const char *err, va_list params) NORETURN);
47 
48 #define pr_debug(fmt, ...)						\
49 	do {								\
50 		if (do_debug_print)					\
51 			__pr_debug("(%s) %s:%d: " fmt, __FILE__,	\
52 				__func__, __LINE__, ##__VA_ARGS__);	\
53 	} while (0)
54 
55 
56 #define BUILD_BUG_ON(condition)	((void)sizeof(char[1 - 2*!!(condition)]))
57 
58 #ifndef BUG_ON_HANDLER
59 # define BUG_ON_HANDLER(condition)					\
60 	do {								\
61 		if ((condition)) {					\
62 			pr_err("BUG at %s:%d", __FILE__, __LINE__);	\
63 			raise(SIGABRT);					\
64 		}							\
65 	} while (0)
66 #endif
67 
68 #define BUG_ON(condition)	BUG_ON_HANDLER((condition))
69 
70 #define DIE_IF(cnd)						\
71 do {								\
72 	if (cnd)						\
73 	die(" at (" __FILE__ ":" __stringify(__LINE__) "): "	\
74 		__stringify(cnd) "\n");				\
75 } while (0)
76 
77 #define WARN_ON(condition) ({					\
78 	int __ret_warn_on = !!(condition);			\
79 	if (__ret_warn_on)					\
80 		pr_warning("(%s) %s:%d: failed condition: %s",	\
81 				__FILE__, __func__, __LINE__,	\
82 				__stringify(condition));	\
83 	__ret_warn_on;						\
84 })
85 
86 #define WARN_ONCE(condition, format, args...) ({	\
87 	static int __warned;							\
88 	int __ret_warn_on = !!(condition);				\
89 	if (!__warned && __ret_warn_on) {				\
90 		__warned = 1;								\
91 		pr_warning(format, args);					\
92 	}												\
93 	__ret_warn_on;									\
94 })
95 
96 #define MSECS_TO_USECS(s) ((s) * 1000)
97 
98 /* Millisecond sleep */
99 static inline void msleep(unsigned int msecs)
100 {
101 	usleep(MSECS_TO_USECS(msecs));
102 }
103 
104 /*
105  * Find last (most significant) bit set. Same implementation as Linux:
106  * fls(0) = 0, fls(1) = 1, fls(1UL << 63) = 64
107  */
108 static inline int fls_long(unsigned long x)
109 {
110 	return x ? sizeof(x) * 8 - __builtin_clzl(x) : 0;
111 }
112 
113 static inline unsigned long roundup_pow_of_two(unsigned long x)
114 {
115 	return x ? 1UL << fls_long(x - 1) : 0;
116 }
117 
118 #define is_power_of_two(x)	((x) > 0 ? ((x) & ((x) - 1)) == 0 : 0)
119 
120 /**
121  * pow2_size: return the number of bits needed to store values
122  * @x: number of distinct values to store (or number of bytes)
123  *
124  * Determines the number of bits needed to store @x different values.
125  * Could be used to determine the number of address bits needed to
126  * store @x bytes.
127  *
128  * Example:
129  * pow2_size(255) => 8
130  * pow2_size(256) => 8
131  * pow2_size(257) => 9
132  *
133  * Return: number of bits
134  */
135 static inline int pow2_size(unsigned long x)
136 {
137 	if (x <= 1)
138 		return x;
139 
140 	return sizeof(x) * 8 - __builtin_clzl(x - 1);
141 }
142 
143 struct kvm;
144 void *mmap_hugetlbfs(struct kvm *kvm, const char *htlbfs_path, u64 size);
145 void *mmap_anon_or_hugetlbfs(struct kvm *kvm, const char *hugetlbfs_path, u64 size);
146 
147 #endif /* KVM__UTIL_H */
148