process.cc revision 11854 
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/misc.hh"
38#include "cpu/thread_context.hh"
39#include "debug/Loader.hh"
40#include "mem/page_table.hh"
41#include "sim/aux_vector.hh"
42#include "sim/byteswap.hh"
43#include "sim/process_impl.hh"
44#include "sim/syscall_return.hh"
45#include "sim/system.hh"
46
47using namespace AlphaISA;
48using namespace std;
49
50AlphaProcess::AlphaProcess(ProcessParams *params, ObjectFile *objFile)
51    : Process(params, objFile)
52{
53    brk_point = objFile->dataBase() + objFile->dataSize() + objFile->bssSize();
54    brk_point = roundUp(brk_point, PageBytes);
55
56    // Set up stack.  On Alpha, stack goes below text section.  This
57    // code should get moved to some architecture-specific spot.
58    stack_base = objFile->textBase() - (409600+4096);
59
60    // Set up region for mmaps.  Tru64 seems to start just above 0 and
61    // grow up from there.
62    mmap_end = 0x10000;
63
64    // Set pointer for next thread stack.  Reserve 8M for main stack.
65    next_thread_stack_base = stack_base - (8 * 1024 * 1024);
66
67}
68
69void
70AlphaProcess::argsInit(int intSize, int pageSize)
71{
72    // Patch the ld_bias for dynamic executables.
73    updateBias();
74
75    objFile->loadSections(initVirtMem);
76
77    typedef AuxVector<uint64_t> auxv_t;
78    std::vector<auxv_t>  auxv;
79
80    ElfObject * elfObject = dynamic_cast<ElfObject *>(objFile);
81    if (elfObject)
82    {
83        // modern glibc uses a bunch of auxiliary vectors to set up
84        // TLS as well as do a bunch of other stuff
85        // these vectors go on the bottom of the stack, below argc/argv/envp
86        // pointers but above actual arg strings
87        // I don't have all the ones glibc looks at here, but so far it doesn't
88        // seem to be a problem.
89        // check out _dl_aux_init() in glibc/elf/dl-support.c for details
90        // --Lisa
91        auxv.push_back(auxv_t(M5_AT_PAGESZ, AlphaISA::PageBytes));
92        auxv.push_back(auxv_t(M5_AT_CLKTCK, 100));
93        auxv.push_back(auxv_t(M5_AT_PHDR, elfObject->programHeaderTable()));
94        DPRINTF(Loader, "auxv at PHDR %08p\n", elfObject->programHeaderTable());
95        auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount()));
96        // This is the base address of the ELF interpreter; it should be
97        // zero for static executables or contain the base address for
98        // dynamic executables.
99        auxv.push_back(auxv_t(M5_AT_BASE, getBias()));
100        auxv.push_back(auxv_t(M5_AT_ENTRY, objFile->entryPoint()));
101        auxv.push_back(auxv_t(M5_AT_UID, uid()));
102        auxv.push_back(auxv_t(M5_AT_EUID, euid()));
103        auxv.push_back(auxv_t(M5_AT_GID, gid()));
104        auxv.push_back(auxv_t(M5_AT_EGID, egid()));
105
106    }
107
108    // Calculate how much space we need for arg & env & auxv arrays.
109    int argv_array_size = intSize * (argv.size() + 1);
110    int envp_array_size = intSize * (envp.size() + 1);
111    int auxv_array_size = intSize * 2 * (auxv.size() + 1);
112
113    int arg_data_size = 0;
114    for (vector<string>::size_type i = 0; i < argv.size(); ++i) {
115        arg_data_size += argv[i].size() + 1;
116    }
117    int env_data_size = 0;
118    for (vector<string>::size_type i = 0; i < envp.size(); ++i) {
119        env_data_size += envp[i].size() + 1;
120    }
121
122    int space_needed =
123        argv_array_size +
124        envp_array_size +
125        auxv_array_size +
126        arg_data_size +
127        env_data_size;
128
129    if (space_needed < 32*1024)
130        space_needed = 32*1024;
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    allocateMem(stack_min, roundUp(stack_size, pageSize));
139
140    // map out initial stack contents
141    Addr argv_array_base = stack_min + intSize; // room for argc
142    Addr envp_array_base = argv_array_base + argv_array_size;
143    Addr auxv_array_base = envp_array_base + envp_array_size;
144    Addr arg_data_base = auxv_array_base + auxv_array_size;
145    Addr env_data_base = arg_data_base + arg_data_size;
146
147    // write contents to stack
148    uint64_t argc = argv.size();
149    if (intSize == 8)
150        argc = htog((uint64_t)argc);
151    else if (intSize == 4)
152        argc = htog((uint32_t)argc);
153    else
154        panic("Unknown int size");
155
156    initVirtMem.writeBlob(stack_min, (uint8_t*)&argc, intSize);
157
158    copyStringArray(argv, argv_array_base, arg_data_base, initVirtMem);
159    copyStringArray(envp, envp_array_base, env_data_base, initVirtMem);
160
161    //Copy the aux stuff
162    for (vector<auxv_t>::size_type x = 0; x < auxv.size(); x++) {
163        initVirtMem.writeBlob(auxv_array_base + x * 2 * intSize,
164                (uint8_t*)&(auxv[x].a_type), intSize);
165        initVirtMem.writeBlob(auxv_array_base + (x * 2 + 1) * intSize,
166                (uint8_t*)&(auxv[x].a_val), intSize);
167    }
168
169    ThreadContext *tc = system->getThreadContext(contextIds[0]);
170
171    setSyscallArg(tc, 0, argc);
172    setSyscallArg(tc, 1, argv_array_base);
173    tc->setIntReg(StackPointerReg, stack_min);
174
175    tc->pcState(getStartPC());
176}
177
178void
179AlphaProcess::setupASNReg()
180{
181    ThreadContext *tc = system->getThreadContext(contextIds[0]);
182    tc->setMiscRegNoEffect(IPR_DTB_ASN, _pid << 57);
183}
184
185
186void
187AlphaProcess::loadState(CheckpointIn &cp)
188{
189    Process::loadState(cp);
190    // need to set up ASN after unserialization since _pid value may
191    // come from checkpoint
192    setupASNReg();
193}
194
195
196void
197AlphaProcess::initState()
198{
199    // need to set up ASN before further initialization since init
200    // will involve writing to virtual memory addresses
201    setupASNReg();
202
203    Process::initState();
204
205    argsInit(MachineBytes, PageBytes);
206
207    ThreadContext *tc = system->getThreadContext(contextIds[0]);
208    tc->setIntReg(GlobalPointerReg, objFile->globalPointer());
209    //Operate in user mode
210    tc->setMiscRegNoEffect(IPR_ICM, mode_user << 3);
211    tc->setMiscRegNoEffect(IPR_DTB_CM, mode_user << 3);
212    //No super page mapping
213    tc->setMiscRegNoEffect(IPR_MCSR, 0);
214}
215
216AlphaISA::IntReg
217AlphaProcess::getSyscallArg(ThreadContext *tc, int &i)
218{
219    assert(i < 6);
220    return tc->readIntReg(FirstArgumentReg + i++);
221}
222
223void
224AlphaProcess::setSyscallArg(ThreadContext *tc, int i, AlphaISA::IntReg val)
225{
226    assert(i < 6);
227    tc->setIntReg(FirstArgumentReg + i, val);
228}
229
230void
231AlphaProcess::setSyscallReturn(ThreadContext *tc, SyscallReturn sysret)
232{
233    // check for error condition.  Alpha syscall convention is to
234    // indicate success/failure in reg a3 (r19) and put the
235    // return value itself in the standard return value reg (v0).
236    if (sysret.successful()) {
237        // no error
238        tc->setIntReg(SyscallSuccessReg, 0);
239        tc->setIntReg(ReturnValueReg, sysret.returnValue());
240    } else {
241        // got an error, return details
242        tc->setIntReg(SyscallSuccessReg, (IntReg)-1);
243        tc->setIntReg(ReturnValueReg, sysret.errnoValue());
244    }
245}
246