process.cc revision 7720 
1/*
2 * Copyright (c) 2004-2005 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 * Authors: Gabe Black
29 *          Ali Saidi
30 *          Korey Sewell
31 */
32
33#include "arch/mips/isa_traits.hh"
34#include "arch/mips/process.hh"
35#include "base/loader/object_file.hh"
36#include "base/loader/elf_object.hh"
37#include "base/misc.hh"
38#include "cpu/thread_context.hh"
39#include "mem/page_table.hh"
40#include "sim/process.hh"
41#include "sim/process_impl.hh"
42#include "sim/system.hh"
43
44using namespace std;
45using namespace MipsISA;
46
47MipsLiveProcess::MipsLiveProcess(LiveProcessParams * params,
48        ObjectFile *objFile)
49    : LiveProcess(params, objFile)
50{
51    // Set up stack. On MIPS, stack starts at the top of kuseg
52    // user address space. MIPS stack grows down from here
53    stack_base = 0x7FFFFFFF;
54
55    // Set pointer for next thread stack.  Reserve 8M for main stack.
56    next_thread_stack_base = stack_base - (8 * 1024 * 1024);
57
58    // Set up break point (Top of Heap)
59    brk_point = objFile->dataBase() + objFile->dataSize() + objFile->bssSize();
60    brk_point = roundUp(brk_point, VMPageSize);
61
62    // Set up region for mmaps.  Start it 1GB above the top of the heap.
63    mmap_start = mmap_end = brk_point + 0x40000000L;
64}
65
66void
67MipsLiveProcess::initState()
68{
69    LiveProcess::initState();
70
71    argsInit<uint32_t>(VMPageSize);
72}
73
74template<class IntType>
75void
76MipsLiveProcess::argsInit(int pageSize)
77{
78    int intSize = sizeof(IntType);
79
80    // load object file into target memory
81    objFile->loadSections(initVirtMem);
82
83    typedef AuxVector<IntType> auxv_t;
84    std::vector<auxv_t> auxv;
85
86    ElfObject * elfObject = dynamic_cast<ElfObject *>(objFile);
87    if (elfObject)
88    {
89        // Set the system page size
90        auxv.push_back(auxv_t(M5_AT_PAGESZ, MipsISA::VMPageSize));
91        // Set the frequency at which time() increments
92        auxv.push_back(auxv_t(M5_AT_CLKTCK, 100));
93        // For statically linked executables, this is the virtual
94        // address of the program header tables if they appear in the
95        // executable image.
96        auxv.push_back(auxv_t(M5_AT_PHDR, elfObject->programHeaderTable()));
97        DPRINTF(Loader, "auxv at PHDR %08p\n", elfObject->programHeaderTable());
98        // This is the size of a program header entry from the elf file.
99        auxv.push_back(auxv_t(M5_AT_PHENT, elfObject->programHeaderSize()));
100        // This is the number of program headers from the original elf file.
101        auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount()));
102        //The entry point to the program
103        auxv.push_back(auxv_t(M5_AT_ENTRY, objFile->entryPoint()));
104        //Different user and group IDs
105        auxv.push_back(auxv_t(M5_AT_UID, uid()));
106        auxv.push_back(auxv_t(M5_AT_EUID, euid()));
107        auxv.push_back(auxv_t(M5_AT_GID, gid()));
108        auxv.push_back(auxv_t(M5_AT_EGID, egid()));
109    }
110
111    // Calculate how much space we need for arg & env & auxv arrays.
112    int argv_array_size = intSize * (argv.size() + 1);
113    int envp_array_size = intSize * (envp.size() + 1);
114    int auxv_array_size = intSize * 2 * (auxv.size() + 1);
115
116    int arg_data_size = 0;
117    for (vector<string>::size_type i = 0; i < argv.size(); ++i) {
118        arg_data_size += argv[i].size() + 1;
119    }
120    int env_data_size = 0;
121    for (vector<string>::size_type i = 0; i < envp.size(); ++i) {
122        env_data_size += envp[i].size() + 1;
123    }
124
125    int space_needed =
126        argv_array_size +
127        envp_array_size +
128        auxv_array_size +
129        arg_data_size +
130        env_data_size;
131
132    // set bottom of stack
133    stack_min = stack_base - space_needed;
134    // align it
135    stack_min = roundDown(stack_min, pageSize);
136    stack_size = stack_base - stack_min;
137    // map memory
138    pTable->allocate(stack_min, roundUp(stack_size, pageSize));
139
140    // map out initial stack contents
141    IntType argv_array_base = stack_min + intSize; // room for argc
142    IntType envp_array_base = argv_array_base + argv_array_size;
143    IntType auxv_array_base = envp_array_base + envp_array_size;
144    IntType arg_data_base = auxv_array_base + auxv_array_size;
145    IntType env_data_base = arg_data_base + arg_data_size;
146
147    // write contents to stack
148    IntType argc = argv.size();
149
150    argc = htog((IntType)argc);
151
152    initVirtMem->writeBlob(stack_min, (uint8_t*)&argc, intSize);
153
154    copyStringArray(argv, argv_array_base, arg_data_base, initVirtMem);
155
156    copyStringArray(envp, envp_array_base, env_data_base, initVirtMem);
157
158    // Copy the aux vector
159    for (typename vector<auxv_t>::size_type x = 0; x < auxv.size(); x++) {
160        initVirtMem->writeBlob(auxv_array_base + x * 2 * intSize,
161                (uint8_t*)&(auxv[x].a_type), intSize);
162        initVirtMem->writeBlob(auxv_array_base + (x * 2 + 1) * intSize,
163                (uint8_t*)&(auxv[x].a_val), intSize);
164    }
165
166    // Write out the terminating zeroed auxilliary vector
167    for (unsigned i = 0; i < 2; i++) {
168        const IntType zero = 0;
169        const Addr addr = auxv_array_base + 2 * intSize * (auxv.size() + i);
170        initVirtMem->writeBlob(addr, (uint8_t*)&zero, intSize);
171    }
172
173    ThreadContext *tc = system->getThreadContext(contextIds[0]);
174
175    setSyscallArg(tc, 0, argc);
176    setSyscallArg(tc, 1, argv_array_base);
177    tc->setIntReg(StackPointerReg, stack_min);
178
179    tc->pcState(objFile->entryPoint());
180}
181
182
183MipsISA::IntReg
184MipsLiveProcess::getSyscallArg(ThreadContext *tc, int &i)
185{
186    assert(i < 6);
187    return tc->readIntReg(FirstArgumentReg + i++);
188}
189
190void
191MipsLiveProcess::setSyscallArg(ThreadContext *tc,
192        int i, MipsISA::IntReg val)
193{
194    assert(i < 6);
195    tc->setIntReg(FirstArgumentReg + i, val);
196}
197
198void
199MipsLiveProcess::setSyscallReturn(ThreadContext *tc,
200        SyscallReturn return_value)
201{
202    if (return_value.successful()) {
203        // no error
204        tc->setIntReg(SyscallSuccessReg, 0);
205        tc->setIntReg(ReturnValueReg, return_value.value());
206    } else {
207        // got an error, return details
208        tc->setIntReg(SyscallSuccessReg, (IntReg) -1);
209        tc->setIntReg(ReturnValueReg, -return_value.value());
210    }
211}
212