process.cc revision 13614 
1/*
2 * Copyright (c) 2003-2004 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: Gabe Black
29 *          Ali Saidi
30 */
31
32#include "arch/alpha/process.hh"
33
34#include "arch/alpha/isa_traits.hh"
35#include "base/loader/elf_object.hh"
36#include "base/loader/object_file.hh"
37#include "base/logging.hh"
38#include "cpu/thread_context.hh"
39#include "debug/Loader.hh"
40#include "mem/page_table.hh"
41#include "params/Process.hh"
42#include "sim/aux_vector.hh"
43#include "sim/byteswap.hh"
44#include "sim/process_impl.hh"
45#include "sim/syscall_return.hh"
46#include "sim/system.hh"
47
48using namespace AlphaISA;
49using namespace std;
50
51AlphaProcess::AlphaProcess(ProcessParams *params, ObjectFile *objFile)
52    : Process(params,
53              new EmulationPageTable(params->name, params->pid, PageBytes),
54      objFile)
55{
56    fatal_if(params->useArchPT, "Arch page tables not implemented.");
57    Addr brk_point = objFile->dataBase() + objFile->dataSize() +
58                     objFile->bssSize();
59    brk_point = roundUp(brk_point, PageBytes);
60
61    // Set up stack.  On Alpha, stack goes below text section.  This
62    // code should get moved to some architecture-specific spot.
63    Addr stack_base = objFile->textBase() - (409600+4096);
64
65    // Set up region for mmaps.
66    Addr mmap_end = 0x10000;
67
68    Addr max_stack_size = 8 * 1024 * 1024;
69
70    // Set pointer for next thread stack.  Reserve 8M for main stack.
71    Addr next_thread_stack_base = stack_base - max_stack_size;
72
73    memState = make_shared<MemState>(brk_point, stack_base, max_stack_size,
74                                     next_thread_stack_base, mmap_end);
75}
76
77void
78AlphaProcess::argsInit(int intSize, int pageSize)
79{
80    // Patch the ld_bias for dynamic executables.
81    updateBias();
82
83    objFile->loadSections(initVirtMem);
84
85    typedef AuxVector<uint64_t> auxv_t;
86    std::vector<auxv_t>  auxv;
87
88    ElfObject * elfObject = dynamic_cast<ElfObject *>(objFile);
89    if (elfObject)
90    {
91        // modern glibc uses a bunch of auxiliary vectors to set up
92        // TLS as well as do a bunch of other stuff
93        // these vectors go on the bottom of the stack, below argc/argv/envp
94        // pointers but above actual arg strings
95        // I don't have all the ones glibc looks at here, but so far it doesn't
96        // seem to be a problem.
97        // check out _dl_aux_init() in glibc/elf/dl-support.c for details
98        // --Lisa
99        auxv.push_back(auxv_t(M5_AT_PAGESZ, AlphaISA::PageBytes));
100        auxv.push_back(auxv_t(M5_AT_CLKTCK, 100));
101        auxv.push_back(auxv_t(M5_AT_PHDR, elfObject->programHeaderTable()));
102        DPRINTF(Loader, "auxv at PHDR %08p\n", elfObject->programHeaderTable());
103        auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount()));
104        // This is the base address of the ELF interpreter; it should be
105        // zero for static executables or contain the base address for
106        // dynamic executables.
107        auxv.push_back(auxv_t(M5_AT_BASE, getBias()));
108        auxv.push_back(auxv_t(M5_AT_ENTRY, objFile->entryPoint()));
109        auxv.push_back(auxv_t(M5_AT_UID, uid()));
110        auxv.push_back(auxv_t(M5_AT_EUID, euid()));
111        auxv.push_back(auxv_t(M5_AT_GID, gid()));
112        auxv.push_back(auxv_t(M5_AT_EGID, egid()));
113
114    }
115
116    // Calculate how much space we need for arg & env & auxv arrays.
117    int argv_array_size = intSize * (argv.size() + 1);
118    int envp_array_size = intSize * (envp.size() + 1);
119    int auxv_array_size = intSize * 2 * (auxv.size() + 1);
120
121    int arg_data_size = 0;
122    for (vector<string>::size_type i = 0; i < argv.size(); ++i) {
123        arg_data_size += argv[i].size() + 1;
124    }
125    int env_data_size = 0;
126    for (vector<string>::size_type i = 0; i < envp.size(); ++i) {
127        env_data_size += envp[i].size() + 1;
128    }
129
130    int space_needed =
131        argv_array_size +
132        envp_array_size +
133        auxv_array_size +
134        arg_data_size +
135        env_data_size;
136
137    if (space_needed < 32*1024)
138        space_needed = 32*1024;
139
140    // set bottom of stack
141    memState->setStackMin(memState->getStackBase() - space_needed);
142    // align it
143    memState->setStackMin(roundDown(memState->getStackMin(), pageSize));
144    memState->setStackSize(memState->getStackBase() - memState->getStackMin());
145    // map memory
146    allocateMem(memState->getStackMin(), roundUp(memState->getStackSize(),
147                pageSize));
148
149    // map out initial stack contents
150    Addr argv_array_base = memState->getStackMin() + intSize; // room for argc
151    Addr envp_array_base = argv_array_base + argv_array_size;
152    Addr auxv_array_base = envp_array_base + envp_array_size;
153    Addr arg_data_base = auxv_array_base + auxv_array_size;
154    Addr env_data_base = arg_data_base + arg_data_size;
155
156    // write contents to stack
157    uint64_t argc = argv.size();
158    if (intSize == 8)
159        argc = htog((uint64_t)argc);
160    else if (intSize == 4)
161        argc = htog((uint32_t)argc);
162    else
163        panic("Unknown int size");
164
165    initVirtMem.writeBlob(memState->getStackMin(), (uint8_t*)&argc, intSize);
166
167    copyStringArray(argv, argv_array_base, arg_data_base, initVirtMem);
168    copyStringArray(envp, envp_array_base, env_data_base, initVirtMem);
169
170    //Copy the aux stuff
171    for (vector<auxv_t>::size_type x = 0; x < auxv.size(); x++) {
172        initVirtMem.writeBlob(auxv_array_base + x * 2 * intSize,
173                (uint8_t*)&(auxv[x].getAuxType()), intSize);
174        initVirtMem.writeBlob(auxv_array_base + (x * 2 + 1) * intSize,
175                (uint8_t*)&(auxv[x].getAuxVal()), intSize);
176    }
177
178    ThreadContext *tc = system->getThreadContext(contextIds[0]);
179
180    setSyscallArg(tc, 0, argc);
181    setSyscallArg(tc, 1, argv_array_base);
182    tc->setIntReg(StackPointerReg, memState->getStackMin());
183
184    tc->pcState(getStartPC());
185}
186
187void
188AlphaProcess::setupASNReg()
189{
190    ThreadContext *tc = system->getThreadContext(contextIds[0]);
191    tc->setMiscRegNoEffect(IPR_DTB_ASN, _pid << 57);
192}
193
194
195void
196AlphaProcess::unserialize(CheckpointIn &cp)
197{
198    Process::unserialize(cp);
199    // need to set up ASN after unserialization since _pid value may
200    // come from checkpoint
201    setupASNReg();
202}
203
204
205void
206AlphaProcess::initState()
207{
208    // need to set up ASN before further initialization since init
209    // will involve writing to virtual memory addresses
210    setupASNReg();
211
212    Process::initState();
213
214    argsInit(MachineBytes, PageBytes);
215
216    ThreadContext *tc = system->getThreadContext(contextIds[0]);
217    tc->setIntReg(GlobalPointerReg, objFile->globalPointer());
218    //Operate in user mode
219    tc->setMiscRegNoEffect(IPR_ICM, mode_user << 3);
220    tc->setMiscRegNoEffect(IPR_DTB_CM, mode_user << 3);
221    //No super page mapping
222    tc->setMiscRegNoEffect(IPR_MCSR, 0);
223}
224
225RegVal
226AlphaProcess::getSyscallArg(ThreadContext *tc, int &i)
227{
228    assert(i < 6);
229    return tc->readIntReg(FirstArgumentReg + i++);
230}
231
232void
233AlphaProcess::setSyscallArg(ThreadContext *tc, int i, RegVal val)
234{
235    assert(i < 6);
236    tc->setIntReg(FirstArgumentReg + i, val);
237}
238
239void
240AlphaProcess::setSyscallReturn(ThreadContext *tc, SyscallReturn sysret)
241{
242    // check for error condition.  Alpha syscall convention is to
243    // indicate success/failure in reg a3 (r19) and put the
244    // return value itself in the standard return value reg (v0).
245    if (sysret.successful()) {
246        // no error
247        tc->setIntReg(SyscallSuccessReg, 0);
248        tc->setIntReg(ReturnValueReg, sysret.returnValue());
249    } else {
250        // got an error, return details
251        tc->setIntReg(SyscallSuccessReg, (RegVal)-1);
252        tc->setIntReg(ReturnValueReg, sysret.errnoValue());
253    }
254}
255