xref: /kvmtool/util/util.c (revision fc184a682a2164c156655ec18bc4a18bb638f644)
1 /*
2  * Taken from perf which in turn take it from GIT
3  */
4 
5 #include "kvm/util.h"
6 
7 #include <kvm/kvm.h>
8 #include <linux/magic.h>	/* For HUGETLBFS_MAGIC */
9 #include <sys/mman.h>
10 #include <sys/stat.h>
11 #include <sys/statfs.h>
12 
13 static void report(const char *prefix, const char *err, va_list params)
14 {
15 	char msg[1024];
16 	vsnprintf(msg, sizeof(msg), err, params);
17 	fprintf(stderr, " %s%s\n", prefix, msg);
18 }
19 
20 static NORETURN void die_builtin(const char *err, va_list params)
21 {
22 	report(" Fatal: ", err, params);
23 	exit(128);
24 }
25 
26 static void error_builtin(const char *err, va_list params)
27 {
28 	report(" Error: ", err, params);
29 }
30 
31 static void warn_builtin(const char *warn, va_list params)
32 {
33 	report(" Warning: ", warn, params);
34 }
35 
36 static void info_builtin(const char *info, va_list params)
37 {
38 	report(" Info: ", info, params);
39 }
40 
41 static void debug_builtin(const char *debug, va_list params)
42 {
43 	report(" Debug: ", debug, params);
44 }
45 
46 void die(const char *err, ...)
47 {
48 	va_list params;
49 
50 	va_start(params, err);
51 	die_builtin(err, params);
52 	va_end(params);
53 }
54 
55 void pr_err(const char *err, ...)
56 {
57 	va_list params;
58 
59 	va_start(params, err);
60 	error_builtin(err, params);
61 	va_end(params);
62 }
63 
64 void pr_warning(const char *warn, ...)
65 {
66 	va_list params;
67 
68 	va_start(params, warn);
69 	warn_builtin(warn, params);
70 	va_end(params);
71 }
72 
73 void pr_info(const char *info, ...)
74 {
75 	va_list params;
76 
77 	va_start(params, info);
78 	info_builtin(info, params);
79 	va_end(params);
80 }
81 
82 /* Do not call directly; call pr_debug() instead. */
83 void __pr_debug(const char *debug, ...)
84 {
85 	va_list params;
86 
87 	va_start(params, debug);
88 	debug_builtin(debug, params);
89 	va_end(params);
90 }
91 
92 void die_perror(const char *s)
93 {
94 	perror(s);
95 	exit(1);
96 }
97 
98 void *mmap_hugetlbfs(struct kvm *kvm, const char *htlbfs_path, u64 size)
99 {
100 	char mpath[PATH_MAX];
101 	int fd;
102 	struct statfs sfs;
103 	void *addr;
104 	unsigned long blk_size;
105 
106 	if (statfs(htlbfs_path, &sfs) < 0)
107 		die("Can't stat %s\n", htlbfs_path);
108 
109 	if ((unsigned int)sfs.f_type != HUGETLBFS_MAGIC)
110 		die("%s is not hugetlbfs!\n", htlbfs_path);
111 
112 	blk_size = (unsigned long)sfs.f_bsize;
113 	if (sfs.f_bsize == 0 || blk_size > size) {
114 		die("Can't use hugetlbfs pagesize %ld for mem size %lld\n",
115 			blk_size, (unsigned long long)size);
116 	}
117 
118 	kvm->ram_pagesize = blk_size;
119 
120 	snprintf(mpath, PATH_MAX, "%s/kvmtoolXXXXXX", htlbfs_path);
121 	fd = mkstemp(mpath);
122 	if (fd < 0)
123 		die("Can't open %s for hugetlbfs map\n", mpath);
124 	unlink(mpath);
125 	if (ftruncate(fd, size) < 0)
126 		die("Can't ftruncate for mem mapping size %lld\n",
127 			(unsigned long long)size);
128 	addr = mmap(NULL, size, PROT_RW, MAP_PRIVATE, fd, 0);
129 	close(fd);
130 
131 	return addr;
132 }
133 
134 /* This function wraps the decision between hugetlbfs map (if requested) or normal mmap */
135 void *mmap_anon_or_hugetlbfs(struct kvm *kvm, const char *hugetlbfs_path, u64 size)
136 {
137 	if (hugetlbfs_path)
138 		/*
139 		 * We don't /need/ to map guest RAM from hugetlbfs, but we do so
140 		 * if the user specifies a hugetlbfs path.
141 		 */
142 		return mmap_hugetlbfs(kvm, hugetlbfs_path, size);
143 	else {
144 		kvm->ram_pagesize = getpagesize();
145 		return mmap(NULL, size, PROT_RW, MAP_ANON_NORESERVE, -1, 0);
146 	}
147 }
148