xref: /openbmc/qemu/linux-user/uname.c (revision 93e0932b)
1 /*
2  *  cpu to uname machine name map
3  *
4  *  Copyright (c) 2009 Loïc Minier
5  *
6  *  This program is free software; you can redistribute it and/or modify
7  *  it under the terms of the GNU General Public License as published by
8  *  the Free Software Foundation; either version 2 of the License, or
9  *  (at your option) any later version.
10  *
11  *  This program is distributed in the hope that it will be useful,
12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *  GNU General Public License for more details.
15  *
16  *  You should have received a copy of the GNU General Public License
17  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 
22 #include "qemu.h"
23 #include "user-internals.h"
24 #include "uname.h"
25 
26 /* return highest utsname machine name for emulated instruction set
27  *
28  * NB: the default emulated CPU ("any") might not match any existing CPU, e.g.
29  * on ARM it has all features turned on, so there is no perfect arch string to
30  * return here */
31 const char *cpu_to_uname_machine(CPUArchState *cpu_env)
32 {
33 #if defined(TARGET_ARM) && !defined(TARGET_AARCH64)
34 
35     /* utsname machine name on linux arm is CPU arch name + endianness, e.g.
36      * armv7l; to get a list of CPU arch names from the linux source, use:
37      *     grep arch_name: -A1 linux/arch/arm/mm/proc-*.S
38      * see arch/arm/kernel/setup.c: setup_processor()
39      */
40 
41     /* in theory, endianness is configurable on some ARM CPUs, but this isn't
42      * used in user mode emulation */
43 #if TARGET_BIG_ENDIAN
44 #define utsname_suffix "b"
45 #else
46 #define utsname_suffix "l"
47 #endif
48     if (arm_feature(cpu_env, ARM_FEATURE_V7))
49         return "armv7" utsname_suffix;
50     if (arm_feature(cpu_env, ARM_FEATURE_V6))
51         return "armv6" utsname_suffix;
52     /* earliest emulated CPU is ARMv5TE; qemu can emulate the 1026, but not its
53      * Jazelle support */
54     return "armv5te" utsname_suffix;
55 #elif defined(TARGET_I386) && !defined(TARGET_X86_64)
56     /* see arch/x86/kernel/cpu/bugs.c: check_bugs(), 386, 486, 586, 686 */
57     CPUState *cpu = env_cpu(cpu_env);
58     int family = object_property_get_int(OBJECT(cpu), "family", NULL);
59     if (family == 4) {
60         return "i486";
61     }
62     if (family == 5) {
63         return "i586";
64     }
65     return "i686";
66 #else
67     /* default is #define-d in each arch/ subdir */
68     return UNAME_MACHINE;
69 #endif
70 }
71 
72 
73 #define COPY_UTSNAME_FIELD(dest, src) \
74   do { \
75       memcpy((dest), (src), MIN(sizeof(src), sizeof(dest))); \
76       (dest)[sizeof(dest) - 1] = '\0'; \
77   } while (0)
78 
79 int sys_uname(struct new_utsname *buf)
80 {
81   struct utsname uts_buf;
82 
83   if (uname(&uts_buf) < 0)
84       return (-1);
85 
86   /*
87    * Just in case these have some differences, we
88    * translate utsname to new_utsname (which is the
89    * struct linux kernel uses).
90    */
91 
92   memset(buf, 0, sizeof(*buf));
93   COPY_UTSNAME_FIELD(buf->sysname, uts_buf.sysname);
94   COPY_UTSNAME_FIELD(buf->nodename, uts_buf.nodename);
95   COPY_UTSNAME_FIELD(buf->release, uts_buf.release);
96   COPY_UTSNAME_FIELD(buf->version, uts_buf.version);
97   COPY_UTSNAME_FIELD(buf->machine, uts_buf.machine);
98 #ifdef _GNU_SOURCE
99   COPY_UTSNAME_FIELD(buf->domainname, uts_buf.domainname);
100 #endif
101   return (0);
102 
103 #undef COPY_UTSNAME_FIELD
104 }
105 
106 static int relstr_to_int(const char *s)
107 {
108     /* Convert a uname release string like "2.6.18" to an integer
109      * of the form 0x020612. (Beware that 0x020612 is *not* 2.6.12.)
110      */
111     int i, n, tmp;
112 
113     tmp = 0;
114     for (i = 0; i < 3; i++) {
115         n = 0;
116         while (*s >= '0' && *s <= '9') {
117             n *= 10;
118             n += *s - '0';
119             s++;
120         }
121         tmp = (tmp << 8) + n;
122         if (*s == '.') {
123             s++;
124         }
125     }
126     return tmp;
127 }
128 
129 int get_osversion(void)
130 {
131     static int osversion;
132     struct new_utsname buf;
133     const char *s;
134 
135     if (osversion)
136         return osversion;
137     if (qemu_uname_release && *qemu_uname_release) {
138         s = qemu_uname_release;
139     } else {
140         if (sys_uname(&buf))
141             return 0;
142         s = buf.release;
143     }
144     osversion = relstr_to_int(s);
145     return osversion;
146 }
147 
148 void init_qemu_uname_release(void)
149 {
150     /* Initialize qemu_uname_release for later use.
151      * If the host kernel is too old and the user hasn't asked for
152      * a specific fake version number, we might want to fake a minimum
153      * target kernel version.
154      */
155     struct new_utsname buf;
156 
157     if (qemu_uname_release && *qemu_uname_release) {
158         return;
159     }
160 
161     if (sys_uname(&buf)) {
162         return;
163     }
164 
165     if (relstr_to_int(buf.release) < relstr_to_int(UNAME_MINIMUM_RELEASE)) {
166         qemu_uname_release = UNAME_MINIMUM_RELEASE;
167     }
168 }
169