linux.cc revision 13883:f44e21d3aaa7 
1/*
2 * Copyright (c) 2009 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Ali Saidi
29 */
30
31#include "kern/linux/linux.hh"
32
33#include <cstdio>
34#include <string>
35
36#include "cpu/base.hh"
37#include "debug/SyscallVerbose.hh"
38#include "sim/process.hh"
39#include "sim/system.hh"
40
41int
42Linux::openSpecialFile(std::string path, Process *process,
43                       ThreadContext *tc)
44{
45    DPRINTFR(SyscallVerbose,
46             "%d: %s: generic-open: opening special file: %s\n",
47             curTick(), tc->getCpuPtr()->name(), path.c_str());
48
49    bool matched = false;
50    std::string data;
51
52    if (path.compare(0, 13, "/proc/meminfo") == 0) {
53        data = Linux::procMeminfo(process, tc);
54        matched = true;
55    } else if (path.compare(0, 11, "/etc/passwd") == 0) {
56        data = Linux::etcPasswd(process, tc);
57        matched = true;
58    } else if (path.compare(0, 30, "/sys/devices/system/cpu/online") == 0) {
59        data = Linux::cpuOnline(process, tc);
60        matched = true;
61    }
62
63    if (matched) {
64        FILE *f = tmpfile();
65        int fd = fileno(f);
66        size_t ret M5_VAR_USED = fwrite(data.c_str(), 1, data.size(), f);
67        assert(ret == data.size());
68        rewind(f);
69        return fd;
70    } else {
71        warn("Attempting to open special file: %s. Ignoring. Simulation may "
72             "take un-expected code path or be non-deterministic until proper "
73             "handling is implemented.\n", path.c_str());
74        errno = EACCES;
75        return -1;
76    }
77}
78
79std::string
80Linux::procMeminfo(Process *process, ThreadContext *tc)
81{
82    return csprintf("MemTotal:%12d kB\nMemFree: %12d kB\n",
83            process->system->memSize() >> 10,
84            process->system->freeMemSize() >> 10);
85}
86
87std::string
88Linux::etcPasswd(Process *process, ThreadContext *tc)
89{
90    return csprintf("gem5-user:x:1000:1000:gem5-user,,,:%s:/bin/bash\n",
91                    process->tgtCwd);
92}
93
94std::string
95Linux::cpuOnline(Process *process, ThreadContext *tc)
96{
97    return csprintf("0-%d\n",
98                    tc->getSystemPtr()->numContexts() - 1);
99}
100