process.cc revision 2632:1bb2f91485ea
1/*
2 * Copyright (c) 2001-2005 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
29#include <unistd.h>
30#include <fcntl.h>
31
32#include <string>
33
34#include "base/intmath.hh"
35#include "base/loader/object_file.hh"
36#include "base/loader/symtab.hh"
37#include "base/statistics.hh"
38#include "config/full_system.hh"
39#include "cpu/exec_context.hh"
40#include "mem/page_table.hh"
41#include "mem/physical.hh"
42#include "mem/translating_port.hh"
43#include "sim/builder.hh"
44#include "sim/process.hh"
45#include "sim/stats.hh"
46#include "sim/syscall_emul.hh"
47#include "sim/system.hh"
48
49using namespace std;
50using namespace TheISA;
51
52//
53// The purpose of this code is to fake the loader & syscall mechanism
54// when there's no OS: thus there's no resone to use it in FULL_SYSTEM
55// mode when we do have an OS
56//
57#if FULL_SYSTEM
58#error "process.cc not compatible with FULL_SYSTEM"
59#endif
60
61// current number of allocated processes
62int num_processes = 0;
63
64Process::Process(const string &nm,
65                 System *_system,
66                 int stdin_fd, 	// initial I/O descriptors
67                 int stdout_fd,
68                 int stderr_fd)
69    : SimObject(nm), system(_system)
70{
71    // initialize first 3 fds (stdin, stdout, stderr)
72    fd_map[STDIN_FILENO] = stdin_fd;
73    fd_map[STDOUT_FILENO] = stdout_fd;
74    fd_map[STDERR_FILENO] = stderr_fd;
75
76    // mark remaining fds as free
77    for (int i = 3; i <= MAX_FD; ++i) {
78        fd_map[i] = -1;
79    }
80
81    mmap_start = mmap_end = 0;
82    nxm_start = nxm_end = 0;
83    pTable = new PageTable(system);
84    // other parameters will be initialized when the program is loaded
85}
86
87
88void
89Process::regStats()
90{
91    using namespace Stats;
92
93    num_syscalls
94        .name(name() + ".PROG:num_syscalls")
95        .desc("Number of system calls")
96        ;
97}
98
99//
100// static helper functions
101//
102int
103Process::openInputFile(const string &filename)
104{
105    int fd = open(filename.c_str(), O_RDONLY);
106
107    if (fd == -1) {
108        perror(NULL);
109        cerr << "unable to open \"" << filename << "\" for reading\n";
110        fatal("can't open input file");
111    }
112
113    return fd;
114}
115
116
117int
118Process::openOutputFile(const string &filename)
119{
120    int fd = open(filename.c_str(), O_WRONLY | O_CREAT | O_TRUNC, 0774);
121
122    if (fd == -1) {
123        perror(NULL);
124        cerr << "unable to open \"" << filename << "\" for writing\n";
125        fatal("can't open output file");
126    }
127
128    return fd;
129}
130
131
132int
133Process::registerExecContext(ExecContext *xc)
134{
135    // add to list
136    int myIndex = execContexts.size();
137    execContexts.push_back(xc);
138
139    // return CPU number to caller
140    return myIndex;
141}
142
143void
144Process::startup()
145{
146    if (execContexts.empty())
147        fatal("Process %s is not associated with any CPUs!\n", name());
148
149    // first exec context for this process... initialize & enable
150    ExecContext *xc = execContexts[0];
151
152    // mark this context as active so it will start ticking.
153    xc->activate(0);
154
155    Port *mem_port;
156    mem_port = system->physmem->getPort("functional");
157    initVirtMem = new TranslatingPort(pTable, true);
158    mem_port->setPeer(initVirtMem);
159    initVirtMem->setPeer(mem_port);
160}
161
162void
163Process::replaceExecContext(ExecContext *xc, int xcIndex)
164{
165    if (xcIndex >= execContexts.size()) {
166        panic("replaceExecContext: bad xcIndex, %d >= %d\n",
167              xcIndex, execContexts.size());
168    }
169
170    execContexts[xcIndex] = xc;
171}
172
173// map simulator fd sim_fd to target fd tgt_fd
174void
175Process::dup_fd(int sim_fd, int tgt_fd)
176{
177    if (tgt_fd < 0 || tgt_fd > MAX_FD)
178        panic("Process::dup_fd tried to dup past MAX_FD (%d)", tgt_fd);
179
180    fd_map[tgt_fd] = sim_fd;
181}
182
183
184// generate new target fd for sim_fd
185int
186Process::alloc_fd(int sim_fd)
187{
188    // in case open() returns an error, don't allocate a new fd
189    if (sim_fd == -1)
190        return -1;
191
192    // find first free target fd
193    for (int free_fd = 0; free_fd < MAX_FD; ++free_fd) {
194        if (fd_map[free_fd] == -1) {
195            fd_map[free_fd] = sim_fd;
196            return free_fd;
197        }
198    }
199
200    panic("Process::alloc_fd: out of file descriptors!");
201}
202
203
204// free target fd (e.g., after close)
205void
206Process::free_fd(int tgt_fd)
207{
208    if (fd_map[tgt_fd] == -1)
209        warn("Process::free_fd: request to free unused fd %d", tgt_fd);
210
211    fd_map[tgt_fd] = -1;
212}
213
214
215// look up simulator fd for given target fd
216int
217Process::sim_fd(int tgt_fd)
218{
219    if (tgt_fd > MAX_FD)
220        return -1;
221
222    return fd_map[tgt_fd];
223}
224
225
226
227//
228// need to declare these here since there is no concrete Process type
229// that can be constructed (i.e., no REGISTER_SIM_OBJECT() macro call,
230// which is where these get declared for concrete types).
231//
232DEFINE_SIM_OBJECT_CLASS_NAME("Process", Process)
233
234
235////////////////////////////////////////////////////////////////////////
236//
237// LiveProcess member definitions
238//
239////////////////////////////////////////////////////////////////////////
240
241
242void
243copyStringArray(vector<string> &strings, Addr array_ptr, Addr data_ptr,
244                TranslatingPort* memPort)
245{
246    Addr data_ptr_swap;
247    for (int i = 0; i < strings.size(); ++i) {
248        data_ptr_swap = htog(data_ptr);
249        memPort->writeBlob(array_ptr, (uint8_t*)&data_ptr_swap, sizeof(Addr));
250        memPort->writeString(data_ptr, strings[i].c_str());
251        array_ptr += sizeof(Addr);
252        data_ptr += strings[i].size() + 1;
253    }
254    // add NULL terminator
255    data_ptr = 0;
256
257    memPort->writeBlob(array_ptr, (uint8_t*)&data_ptr, sizeof(Addr));
258}
259
260LiveProcess::LiveProcess(const string &nm, ObjectFile *_objFile,
261                         System *_system,
262                         int stdin_fd, int stdout_fd, int stderr_fd,
263                         vector<string> &_argv, vector<string> &_envp)
264    : Process(nm, _system, stdin_fd, stdout_fd, stderr_fd),
265      objFile(_objFile), argv(_argv), envp(_envp)
266{
267    prog_fname = argv[0];
268
269    // load up symbols, if any... these may be used for debugging or
270    // profiling.
271    if (!debugSymbolTable) {
272        debugSymbolTable = new SymbolTable();
273        if (!objFile->loadGlobalSymbols(debugSymbolTable) ||
274            !objFile->loadLocalSymbols(debugSymbolTable)) {
275            // didn't load any symbols
276            delete debugSymbolTable;
277            debugSymbolTable = NULL;
278        }
279    }
280}
281
282void
283LiveProcess::argsInit(int intSize, int pageSize)
284{
285    Process::startup();
286
287    // load object file into target memory
288    objFile->loadSections(initVirtMem);
289
290    // Calculate how much space we need for arg & env arrays.
291    int argv_array_size = intSize * (argv.size() + 1);
292    int envp_array_size = intSize * (envp.size() + 1);
293    int arg_data_size = 0;
294    for (int i = 0; i < argv.size(); ++i) {
295        arg_data_size += argv[i].size() + 1;
296    }
297    int env_data_size = 0;
298    for (int i = 0; i < envp.size(); ++i) {
299        env_data_size += envp[i].size() + 1;
300    }
301
302    int space_needed =
303        argv_array_size + envp_array_size + arg_data_size + env_data_size;
304    // for SimpleScalar compatibility
305    if (space_needed < 16384)
306        space_needed = 16384;
307
308    // set bottom of stack
309    stack_min = stack_base - space_needed;
310    // align it
311    stack_min &= ~(intSize-1);
312    stack_size = stack_base - stack_min;
313    // map memory
314    pTable->allocate(roundDown(stack_min, pageSize),
315                     roundUp(stack_size, pageSize));
316
317    // map out initial stack contents
318    Addr argv_array_base = stack_min + intSize; // room for argc
319    Addr envp_array_base = argv_array_base + argv_array_size;
320    Addr arg_data_base = envp_array_base + envp_array_size;
321    Addr env_data_base = arg_data_base + arg_data_size;
322
323    // write contents to stack
324    uint64_t argc = argv.size();
325    if (intSize == 8)
326        argc = htog((uint64_t)argc);
327    else if (intSize == 4)
328        argc = htog((uint32_t)argc);
329    else
330        panic("Unknown int size");
331
332    initVirtMem->writeBlob(stack_min, (uint8_t*)&argc, intSize);
333
334    copyStringArray(argv, argv_array_base, arg_data_base, initVirtMem);
335    copyStringArray(envp, envp_array_base, env_data_base, initVirtMem);
336
337    execContexts[0]->setIntReg(ArgumentReg0, argc);
338    execContexts[0]->setIntReg(ArgumentReg1, argv_array_base);
339    execContexts[0]->setIntReg(StackPointerReg, stack_min);
340
341    Addr prog_entry = objFile->entryPoint();
342    execContexts[0]->setPC(prog_entry);
343    execContexts[0]->setNextPC(prog_entry + sizeof(MachInst));
344    execContexts[0]->setNextNPC(prog_entry + (2 * sizeof(MachInst)));
345
346    num_processes++;
347}
348
349void
350LiveProcess::syscall(int64_t callnum, ExecContext *xc)
351{
352    num_syscalls++;
353
354    SyscallDesc *desc = getDesc(callnum);
355    if (desc == NULL)
356        fatal("Syscall %d out of range", callnum);
357
358    desc->doSyscall(callnum, this, xc);
359}
360
361DEFINE_SIM_OBJECT_CLASS_NAME("LiveProcess", LiveProcess);
362