xref: /kvmtool/util/util.c (revision 2cc4929cc6b9a382a0c866cf5bbe849e3c0ec271)
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 void die(const char *err, ...)
42 {
43 	va_list params;
44 
45 	va_start(params, err);
46 	die_builtin(err, params);
47 	va_end(params);
48 }
49 
50 void pr_err(const char *err, ...)
51 {
52 	va_list params;
53 
54 	va_start(params, err);
55 	error_builtin(err, params);
56 	va_end(params);
57 }
58 
59 void pr_warning(const char *warn, ...)
60 {
61 	va_list params;
62 
63 	va_start(params, warn);
64 	warn_builtin(warn, params);
65 	va_end(params);
66 }
67 
68 void pr_info(const char *info, ...)
69 {
70 	va_list params;
71 
72 	va_start(params, info);
73 	info_builtin(info, params);
74 	va_end(params);
75 }
76 
77 void die_perror(const char *s)
78 {
79 	perror(s);
80 	exit(1);
81 }
82 
83 void *mmap_hugetlbfs(struct kvm *kvm, const char *htlbfs_path, u64 size)
84 {
85 	char mpath[PATH_MAX];
86 	int fd;
87 	struct statfs sfs;
88 	void *addr;
89 	unsigned long blk_size;
90 
91 	if (statfs(htlbfs_path, &sfs) < 0)
92 		die("Can't stat %s\n", htlbfs_path);
93 
94 	if ((unsigned int)sfs.f_type != HUGETLBFS_MAGIC)
95 		die("%s is not hugetlbfs!\n", htlbfs_path);
96 
97 	blk_size = (unsigned long)sfs.f_bsize;
98 	if (sfs.f_bsize == 0 || blk_size > size) {
99 		die("Can't use hugetlbfs pagesize %ld for mem size %lld\n",
100 			blk_size, (unsigned long long)size);
101 	}
102 
103 	kvm->ram_pagesize = blk_size;
104 
105 	snprintf(mpath, PATH_MAX, "%s/kvmtoolXXXXXX", htlbfs_path);
106 	fd = mkstemp(mpath);
107 	if (fd < 0)
108 		die("Can't open %s for hugetlbfs map\n", mpath);
109 	unlink(mpath);
110 	if (ftruncate(fd, size) < 0)
111 		die("Can't ftruncate for mem mapping size %lld\n",
112 			(unsigned long long)size);
113 	addr = mmap(NULL, size, PROT_RW, MAP_PRIVATE, fd, 0);
114 	close(fd);
115 
116 	return addr;
117 }
118 
119 /* This function wraps the decision between hugetlbfs map (if requested) or normal mmap */
120 void *mmap_anon_or_hugetlbfs(struct kvm *kvm, const char *hugetlbfs_path, u64 size)
121 {
122 	if (hugetlbfs_path)
123 		/*
124 		 * We don't /need/ to map guest RAM from hugetlbfs, but we do so
125 		 * if the user specifies a hugetlbfs path.
126 		 */
127 		return mmap_hugetlbfs(kvm, hugetlbfs_path, size);
128 	else {
129 		kvm->ram_pagesize = getpagesize();
130 		return mmap(NULL, size, PROT_RW, MAP_ANON_NORESERVE, -1, 0);
131 	}
132 }
133