process.cc revision 12283:9c8f694f4e97
1/*
2 * Copyright (c) 2014-2016 Advanced Micro Devices, Inc.
3 * Copyright (c) 2012 ARM Limited
4 * All rights reserved
5 *
6 * The license below extends only to copyright in the software and shall
7 * not be construed as granting a license to any other intellectual
8 * property including but not limited to intellectual property relating
9 * to a hardware implementation of the functionality of the software
10 * licensed hereunder.  You may use the software subject to the license
11 * terms below provided that you ensure that this notice is replicated
12 * unmodified and in its entirety in all distributions of the software,
13 * modified or unmodified, in source code or in binary form.
14 *
15 * Copyright (c) 2001-2005 The Regents of The University of Michigan
16 * All rights reserved.
17 *
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted provided that the following conditions are
20 * met: redistributions of source code must retain the above copyright
21 * notice, this list of conditions and the following disclaimer;
22 * redistributions in binary form must reproduce the above copyright
23 * notice, this list of conditions and the following disclaimer in the
24 * documentation and/or other materials provided with the distribution;
25 * neither the name of the copyright holders nor the names of its
26 * contributors may be used to endorse or promote products derived from
27 * this software without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
40 *
41 * Authors: Nathan Binkert
42 *          Steve Reinhardt
43 *          Ali Saidi
44 *          Brandon Potter
45 */
46
47#include "sim/process.hh"
48
49#include <fcntl.h>
50#include <unistd.h>
51
52#include <array>
53#include <csignal>
54#include <map>
55#include <string>
56#include <vector>
57
58#include "base/intmath.hh"
59#include "base/loader/object_file.hh"
60#include "base/loader/symtab.hh"
61#include "base/statistics.hh"
62#include "config/the_isa.hh"
63#include "cpu/thread_context.hh"
64#include "mem/page_table.hh"
65#include "mem/se_translating_port_proxy.hh"
66#include "params/Process.hh"
67#include "sim/emul_driver.hh"
68#include "sim/fd_array.hh"
69#include "sim/fd_entry.hh"
70#include "sim/syscall_desc.hh"
71#include "sim/system.hh"
72
73#if THE_ISA == ALPHA_ISA
74#include "arch/alpha/linux/process.hh"
75
76#elif THE_ISA == SPARC_ISA
77#include "arch/sparc/linux/process.hh"
78#include "arch/sparc/solaris/process.hh"
79
80#elif THE_ISA == MIPS_ISA
81#include "arch/mips/linux/process.hh"
82
83#elif THE_ISA == ARM_ISA
84#include "arch/arm/freebsd/process.hh"
85#include "arch/arm/linux/process.hh"
86
87#elif THE_ISA == X86_ISA
88#include "arch/x86/linux/process.hh"
89
90#elif THE_ISA == POWER_ISA
91#include "arch/power/linux/process.hh"
92
93#elif THE_ISA == RISCV_ISA
94#include "arch/riscv/linux/process.hh"
95
96#else
97#error "THE_ISA not set"
98#endif
99
100
101using namespace std;
102using namespace TheISA;
103
104Process::Process(ProcessParams * params, ObjectFile * obj_file)
105    : SimObject(params), system(params->system),
106      useArchPT(params->useArchPT),
107      kvmInSE(params->kvmInSE),
108      pTable(useArchPT ?
109        static_cast<PageTableBase *>(new ArchPageTable(name(), params->pid,
110            system)) :
111        static_cast<PageTableBase *>(new FuncPageTable(name(), params->pid))),
112      initVirtMem(system->getSystemPort(), this,
113                  SETranslatingPortProxy::Always),
114      objFile(obj_file),
115      argv(params->cmd), envp(params->env), cwd(params->cwd),
116      executable(params->executable),
117      _uid(params->uid), _euid(params->euid),
118      _gid(params->gid), _egid(params->egid),
119      _pid(params->pid), _ppid(params->ppid),
120      _pgid(params->pgid), drivers(params->drivers),
121      fds(make_shared<FDArray>(params->input, params->output, params->errout)),
122      childClearTID(0)
123{
124    if (_pid >= System::maxPID)
125        fatal("_pid is too large: %d", _pid);
126
127    auto ret_pair = system->PIDs.emplace(_pid);
128    if (!ret_pair.second)
129        fatal("_pid %d is already used", _pid);
130
131    /**
132     * Linux bundles together processes into this concept called a thread
133     * group. The thread group is responsible for recording which processes
134     * behave as threads within a process context. The thread group leader
135     * is the process who's tgid is equal to its pid. Other processes which
136     * belong to the thread group, but do not lead the thread group, are
137     * treated as child threads. These threads are created by the clone system
138     * call with options specified to create threads (differing from the
139     * options used to implement a fork). By default, set up the tgid/pid
140     * with a new, equivalent value. If CLONE_THREAD is specified, patch
141     * the tgid value with the old process' value.
142     */
143    _tgid = params->pid;
144
145    exitGroup = new bool();
146    sigchld = new bool();
147
148    if (!debugSymbolTable) {
149        debugSymbolTable = new SymbolTable();
150        if (!objFile->loadGlobalSymbols(debugSymbolTable) ||
151            !objFile->loadLocalSymbols(debugSymbolTable) ||
152            !objFile->loadWeakSymbols(debugSymbolTable)) {
153            delete debugSymbolTable;
154            debugSymbolTable = nullptr;
155        }
156    }
157}
158
159void
160Process::clone(ThreadContext *otc, ThreadContext *ntc,
161               Process *np, TheISA::IntReg flags)
162{
163#ifndef CLONE_VM
164#define CLONE_VM 0
165#endif
166#ifndef CLONE_FILES
167#define CLONE_FILES 0
168#endif
169#ifndef CLONE_THREAD
170#define CLONE_THREAD 0
171#endif
172    if (CLONE_VM & flags) {
173        /**
174         * Share the process memory address space between the new process
175         * and the old process. Changes in one will be visible in the other
176         * due to the pointer use.
177         */
178        delete np->pTable;
179        np->pTable = pTable;
180        ntc->getMemProxy().setPageTable(np->pTable);
181
182        np->memState = memState;
183    } else {
184        /**
185         * Duplicate the process memory address space. The state needs to be
186         * copied over (rather than using pointers to share everything).
187         */
188        typedef std::vector<pair<Addr,Addr>> MapVec;
189        MapVec mappings;
190        pTable->getMappings(&mappings);
191
192        for (auto map : mappings) {
193            Addr paddr, vaddr = map.first;
194            bool alloc_page = !(np->pTable->translate(vaddr, paddr));
195            np->replicatePage(vaddr, paddr, otc, ntc, alloc_page);
196        }
197
198        *np->memState = *memState;
199    }
200
201    if (CLONE_FILES & flags) {
202        /**
203         * The parent and child file descriptors are shared because the
204         * two FDArray pointers are pointing to the same FDArray. Opening
205         * and closing file descriptors will be visible to both processes.
206         */
207        np->fds = fds;
208    } else {
209        /**
210         * Copy the file descriptors from the old process into the new
211         * child process. The file descriptors entry can be opened and
212         * closed independently of the other process being considered. The
213         * host file descriptors are also dup'd so that the flags for the
214         * host file descriptor is independent of the other process.
215         */
216        for (int tgt_fd = 0; tgt_fd < fds->getSize(); tgt_fd++) {
217            std::shared_ptr<FDArray> nfds = np->fds;
218            std::shared_ptr<FDEntry> this_fde = (*fds)[tgt_fd];
219            if (!this_fde) {
220                nfds->setFDEntry(tgt_fd, nullptr);
221                continue;
222            }
223            nfds->setFDEntry(tgt_fd, this_fde->clone());
224
225            auto this_hbfd = std::dynamic_pointer_cast<HBFDEntry>(this_fde);
226            if (!this_hbfd)
227                continue;
228
229            int this_sim_fd = this_hbfd->getSimFD();
230            if (this_sim_fd <= 2)
231                continue;
232
233            int np_sim_fd = dup(this_sim_fd);
234            assert(np_sim_fd != -1);
235
236            auto nhbfd = std::dynamic_pointer_cast<HBFDEntry>((*nfds)[tgt_fd]);
237            nhbfd->setSimFD(np_sim_fd);
238        }
239    }
240
241    if (CLONE_THREAD & flags) {
242        np->_tgid = _tgid;
243        delete np->exitGroup;
244        np->exitGroup = exitGroup;
245    }
246
247    np->argv.insert(np->argv.end(), argv.begin(), argv.end());
248    np->envp.insert(np->envp.end(), envp.begin(), envp.end());
249}
250
251void
252Process::regStats()
253{
254    SimObject::regStats();
255
256    using namespace Stats;
257
258    numSyscalls
259        .name(name() + ".numSyscalls")
260        .desc("Number of system calls")
261        ;
262}
263
264ThreadContext *
265Process::findFreeContext()
266{
267    for (auto &it : system->threadContexts) {
268        if (ThreadContext::Halted == it->status())
269            return it;
270    }
271    return nullptr;
272}
273
274void
275Process::revokeThreadContext(int context_id)
276{
277    std::vector<ContextID>::iterator it;
278    for (it = contextIds.begin(); it != contextIds.end(); it++) {
279        if (*it == context_id) {
280            contextIds.erase(it);
281            return;
282        }
283    }
284    warn("Unable to find thread context to revoke");
285}
286
287void
288Process::initState()
289{
290    if (contextIds.empty())
291        fatal("Process %s is not associated with any HW contexts!\n", name());
292
293    // first thread context for this process... initialize & enable
294    ThreadContext *tc = system->getThreadContext(contextIds[0]);
295
296    // mark this context as active so it will start ticking.
297    tc->activate();
298
299    pTable->initState(tc);
300}
301
302DrainState
303Process::drain()
304{
305    fds->updateFileOffsets();
306    return DrainState::Drained;
307}
308
309void
310Process::allocateMem(Addr vaddr, int64_t size, bool clobber)
311{
312    int npages = divCeil(size, (int64_t)PageBytes);
313    Addr paddr = system->allocPhysPages(npages);
314    pTable->map(vaddr, paddr, size,
315                clobber ? PageTableBase::Clobber : PageTableBase::Zero);
316}
317
318void
319Process::replicatePage(Addr vaddr, Addr new_paddr, ThreadContext *old_tc,
320                       ThreadContext *new_tc, bool allocate_page)
321{
322    if (allocate_page)
323        new_paddr = system->allocPhysPages(1);
324
325    // Read from old physical page.
326    uint8_t *buf_p = new uint8_t[PageBytes];
327    old_tc->getMemProxy().readBlob(vaddr, buf_p, PageBytes);
328
329    // Create new mapping in process address space by clobbering existing
330    // mapping (if any existed) and then write to the new physical page.
331    bool clobber = true;
332    pTable->map(vaddr, new_paddr, PageBytes, clobber);
333    new_tc->getMemProxy().writeBlob(vaddr, buf_p, PageBytes);
334    delete[] buf_p;
335}
336
337bool
338Process::fixupStackFault(Addr vaddr)
339{
340    Addr stack_min = memState->getStackMin();
341    Addr stack_base = memState->getStackBase();
342    Addr max_stack_size = memState->getMaxStackSize();
343
344    // Check if this is already on the stack and there's just no page there
345    // yet.
346    if (vaddr >= stack_min && vaddr < stack_base) {
347        allocateMem(roundDown(vaddr, PageBytes), PageBytes);
348        return true;
349    }
350
351    // We've accessed the next page of the stack, so extend it to include
352    // this address.
353    if (vaddr < stack_min && vaddr >= stack_base - max_stack_size) {
354        while (vaddr < stack_min) {
355            stack_min -= TheISA::PageBytes;
356            if (stack_base - stack_min > max_stack_size)
357                fatal("Maximum stack size exceeded\n");
358            allocateMem(stack_min, TheISA::PageBytes);
359            inform("Increasing stack size by one page.");
360        }
361        memState->setStackMin(stack_min);
362        return true;
363    }
364    return false;
365}
366
367void
368Process::serialize(CheckpointOut &cp) const
369{
370    memState->serialize(cp);
371    pTable->serialize(cp);
372    /**
373     * Checkpoints for file descriptors currently do not work. Need to
374     * come back and fix them at a later date.
375     */
376
377    warn("Checkpoints for file descriptors currently do not work.");
378#if 0
379    for (int x = 0; x < fds->getSize(); x++)
380        (*fds)[x].serializeSection(cp, csprintf("FDEntry%d", x));
381#endif
382
383}
384
385void
386Process::unserialize(CheckpointIn &cp)
387{
388    memState->unserialize(cp);
389    pTable->unserialize(cp);
390    /**
391     * Checkpoints for file descriptors currently do not work. Need to
392     * come back and fix them at a later date.
393     */
394    warn("Checkpoints for file descriptors currently do not work.");
395#if 0
396    for (int x = 0; x < fds->getSize(); x++)
397        (*fds)[x]->unserializeSection(cp, csprintf("FDEntry%d", x));
398    fds->restoreFileOffsets();
399#endif
400    // The above returns a bool so that you could do something if you don't
401    // find the param in the checkpoint if you wanted to, like set a default
402    // but in this case we'll just stick with the instantiated value if not
403    // found.
404}
405
406bool
407Process::map(Addr vaddr, Addr paddr, int size, bool cacheable)
408{
409    pTable->map(vaddr, paddr, size,
410                cacheable ? PageTableBase::Zero : PageTableBase::Uncacheable);
411    return true;
412}
413
414void
415Process::syscall(int64_t callnum, ThreadContext *tc, Fault *fault)
416{
417    numSyscalls++;
418
419    SyscallDesc *desc = getDesc(callnum);
420    if (desc == nullptr)
421        fatal("Syscall %d out of range", callnum);
422
423    desc->doSyscall(callnum, this, tc, fault);
424}
425
426IntReg
427Process::getSyscallArg(ThreadContext *tc, int &i, int width)
428{
429    return getSyscallArg(tc, i);
430}
431
432EmulatedDriver *
433Process::findDriver(std::string filename)
434{
435    for (EmulatedDriver *d : drivers) {
436        if (d->match(filename))
437            return d;
438    }
439
440    return nullptr;
441}
442
443void
444Process::updateBias()
445{
446    ObjectFile *interp = objFile->getInterpreter();
447
448    if (!interp || !interp->relocatable())
449        return;
450
451    // Determine how large the interpreters footprint will be in the process
452    // address space.
453    Addr interp_mapsize = roundUp(interp->mapSize(), TheISA::PageBytes);
454
455    // We are allocating the memory area; set the bias to the lowest address
456    // in the allocated memory region.
457    Addr mmap_end = memState->getMmapEnd();
458    Addr ld_bias = mmapGrowsDown() ? mmap_end - interp_mapsize : mmap_end;
459
460    // Adjust the process mmap area to give the interpreter room; the real
461    // execve system call would just invoke the kernel's internal mmap
462    // functions to make these adjustments.
463    mmap_end = mmapGrowsDown() ? ld_bias : mmap_end + interp_mapsize;
464    memState->setMmapEnd(mmap_end);
465
466    interp->updateBias(ld_bias);
467}
468
469ObjectFile *
470Process::getInterpreter()
471{
472    return objFile->getInterpreter();
473}
474
475Addr
476Process::getBias()
477{
478    ObjectFile *interp = getInterpreter();
479
480    return interp ? interp->bias() : objFile->bias();
481}
482
483Addr
484Process::getStartPC()
485{
486    ObjectFile *interp = getInterpreter();
487
488    return interp ? interp->entryPoint() : objFile->entryPoint();
489}
490
491Process *
492ProcessParams::create()
493{
494    Process *process = nullptr;
495
496    // If not specified, set the executable parameter equal to the
497    // simulated system's zeroth command line parameter
498    if (executable == "") {
499        executable = cmd[0];
500    }
501
502    ObjectFile *obj_file = createObjectFile(executable);
503    if (obj_file == nullptr) {
504        fatal("Can't load object file %s", executable);
505    }
506
507#if THE_ISA == ALPHA_ISA
508    if (obj_file->getArch() != ObjectFile::Alpha)
509        fatal("Object file architecture does not match compiled ISA (Alpha).");
510
511    switch (obj_file->getOpSys()) {
512      case ObjectFile::UnknownOpSys:
513        warn("Unknown operating system; assuming Linux.");
514        // fall through
515      case ObjectFile::Linux:
516        process = new AlphaLinuxProcess(this, obj_file);
517        break;
518
519      default:
520        fatal("Unknown/unsupported operating system.");
521    }
522#elif THE_ISA == SPARC_ISA
523    if (obj_file->getArch() != ObjectFile::SPARC64 &&
524        obj_file->getArch() != ObjectFile::SPARC32)
525        fatal("Object file architecture does not match compiled ISA (SPARC).");
526    switch (obj_file->getOpSys()) {
527      case ObjectFile::UnknownOpSys:
528        warn("Unknown operating system; assuming Linux.");
529        // fall through
530      case ObjectFile::Linux:
531        if (obj_file->getArch() == ObjectFile::SPARC64) {
532            process = new Sparc64LinuxProcess(this, obj_file);
533        } else {
534            process = new Sparc32LinuxProcess(this, obj_file);
535        }
536        break;
537
538      case ObjectFile::Solaris:
539        process = new SparcSolarisProcess(this, obj_file);
540        break;
541
542      default:
543        fatal("Unknown/unsupported operating system.");
544    }
545#elif THE_ISA == X86_ISA
546    if (obj_file->getArch() != ObjectFile::X86_64 &&
547        obj_file->getArch() != ObjectFile::I386)
548        fatal("Object file architecture does not match compiled ISA (x86).");
549    switch (obj_file->getOpSys()) {
550      case ObjectFile::UnknownOpSys:
551        warn("Unknown operating system; assuming Linux.");
552        // fall through
553      case ObjectFile::Linux:
554        if (obj_file->getArch() == ObjectFile::X86_64) {
555            process = new X86_64LinuxProcess(this, obj_file);
556        } else {
557            process = new I386LinuxProcess(this, obj_file);
558        }
559        break;
560
561      default:
562        fatal("Unknown/unsupported operating system.");
563    }
564#elif THE_ISA == MIPS_ISA
565    if (obj_file->getArch() != ObjectFile::Mips)
566        fatal("Object file architecture does not match compiled ISA (MIPS).");
567    switch (obj_file->getOpSys()) {
568      case ObjectFile::UnknownOpSys:
569        warn("Unknown operating system; assuming Linux.");
570        // fall through
571      case ObjectFile::Linux:
572        process = new MipsLinuxProcess(this, obj_file);
573        break;
574
575      default:
576        fatal("Unknown/unsupported operating system.");
577    }
578#elif THE_ISA == ARM_ISA
579    ObjectFile::Arch arch = obj_file->getArch();
580    if (arch != ObjectFile::Arm && arch != ObjectFile::Thumb &&
581        arch != ObjectFile::Arm64)
582        fatal("Object file architecture does not match compiled ISA (ARM).");
583    switch (obj_file->getOpSys()) {
584      case ObjectFile::UnknownOpSys:
585        warn("Unknown operating system; assuming Linux.");
586        // fall through
587      case ObjectFile::Linux:
588        if (arch == ObjectFile::Arm64) {
589            process = new ArmLinuxProcess64(this, obj_file,
590                                            obj_file->getArch());
591        } else {
592            process = new ArmLinuxProcess32(this, obj_file,
593                                            obj_file->getArch());
594        }
595        break;
596      case ObjectFile::FreeBSD:
597        if (arch == ObjectFile::Arm64) {
598            process = new ArmFreebsdProcess64(this, obj_file,
599                                              obj_file->getArch());
600        } else {
601            process = new ArmFreebsdProcess32(this, obj_file,
602                                              obj_file->getArch());
603        }
604        break;
605      case ObjectFile::LinuxArmOABI:
606        fatal("M5 does not support ARM OABI binaries. Please recompile with an"
607              " EABI compiler.");
608      default:
609        fatal("Unknown/unsupported operating system.");
610    }
611#elif THE_ISA == POWER_ISA
612    if (obj_file->getArch() != ObjectFile::Power)
613        fatal("Object file architecture does not match compiled ISA (Power).");
614    switch (obj_file->getOpSys()) {
615      case ObjectFile::UnknownOpSys:
616        warn("Unknown operating system; assuming Linux.");
617        // fall through
618      case ObjectFile::Linux:
619        process = new PowerLinuxProcess(this, obj_file);
620        break;
621
622      default:
623        fatal("Unknown/unsupported operating system.");
624    }
625#elif THE_ISA == RISCV_ISA
626    if (obj_file->getArch() != ObjectFile::Riscv)
627        fatal("Object file architecture does not match compiled ISA (RISCV).");
628    switch (obj_file->getOpSys()) {
629      case ObjectFile::UnknownOpSys:
630        warn("Unknown operating system; assuming Linux.");
631        // fall through
632      case ObjectFile::Linux:
633        process = new RiscvLinuxProcess(this, obj_file);
634        break;
635      default:
636        fatal("Unknown/unsupported operating system.");
637    }
638#else
639#error "THE_ISA not set"
640#endif
641
642    if (process == nullptr)
643        fatal("Unknown error creating process object.");
644    return process;
645}
646
647std::string
648Process::fullPath(const std::string &file_name)
649{
650    if (file_name[0] == '/' || cwd.empty())
651        return file_name;
652
653    std::string full = cwd;
654
655    if (cwd[cwd.size() - 1] != '/')
656        full += '/';
657
658    return full + file_name;
659}
660