process.cc revision 11886:43b882cada33 
1/*
2 * Copyright (c) 2007-2008 The Florida State University
3 * Copyright (c) 2009 The University of Edinburgh
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are
8 * met: redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer;
10 * redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution;
13 * neither the name of the copyright holders nor the names of its
14 * contributors may be used to endorse or promote products derived from
15 * this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 *
29 * Authors: Stephen Hines
30 *          Timothy M. Jones
31 */
32
33#include "arch/power/process.hh"
34
35#include "arch/power/isa_traits.hh"
36#include "arch/power/types.hh"
37#include "base/loader/elf_object.hh"
38#include "base/loader/object_file.hh"
39#include "base/misc.hh"
40#include "cpu/thread_context.hh"
41#include "debug/Stack.hh"
42#include "mem/page_table.hh"
43#include "sim/aux_vector.hh"
44#include "sim/process_impl.hh"
45#include "sim/syscall_return.hh"
46#include "sim/system.hh"
47
48using namespace std;
49using namespace PowerISA;
50
51PowerProcess::PowerProcess(ProcessParams *params, ObjectFile *objFile)
52    : Process(params, objFile)
53{
54    memState->stackBase = 0xbf000000L;
55
56    // Set pointer for next thread stack.  Reserve 8M for main stack.
57    memState->nextThreadStackBase = memState->stackBase - (8 * 1024 * 1024);
58
59    // Set up break point (Top of Heap)
60    memState->brkPoint = objFile->dataBase() + objFile->dataSize() +
61                         objFile->bssSize();
62    memState->brkPoint = roundUp(memState->brkPoint, PageBytes);
63
64    // Set up region for mmaps. For now, start at bottom of kuseg space.
65    memState->mmapEnd = 0x70000000L;
66}
67
68void
69PowerProcess::initState()
70{
71    Process::initState();
72
73    argsInit(MachineBytes, PageBytes);
74}
75
76void
77PowerProcess::argsInit(int intSize, int pageSize)
78{
79    typedef AuxVector<uint32_t> auxv_t;
80    std::vector<auxv_t> auxv;
81
82    string filename;
83    if (argv.size() < 1)
84        filename = "";
85    else
86        filename = argv[0];
87
88    //We want 16 byte alignment
89    uint64_t align = 16;
90
91    // Patch the ld_bias for dynamic executables.
92    updateBias();
93
94    // load object file into target memory
95    objFile->loadSections(initVirtMem);
96
97    //Setup the auxilliary vectors. These will already have endian conversion.
98    //Auxilliary vectors are loaded only for elf formatted executables.
99    ElfObject * elfObject = dynamic_cast<ElfObject *>(objFile);
100    if (elfObject) {
101        uint32_t features = 0;
102
103        //Bits which describe the system hardware capabilities
104        //XXX Figure out what these should be
105        auxv.push_back(auxv_t(M5_AT_HWCAP, features));
106        //The system page size
107        auxv.push_back(auxv_t(M5_AT_PAGESZ, PowerISA::PageBytes));
108        //Frequency at which times() increments
109        auxv.push_back(auxv_t(M5_AT_CLKTCK, 0x64));
110        // For statically linked executables, this is the virtual address of the
111        // program header tables if they appear in the executable image
112        auxv.push_back(auxv_t(M5_AT_PHDR, elfObject->programHeaderTable()));
113        // This is the size of a program header entry from the elf file.
114        auxv.push_back(auxv_t(M5_AT_PHENT, elfObject->programHeaderSize()));
115        // This is the number of program headers from the original elf file.
116        auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount()));
117        // This is the base address of the ELF interpreter; it should be
118        // zero for static executables or contain the base address for
119        // dynamic executables.
120        auxv.push_back(auxv_t(M5_AT_BASE, getBias()));
121        //XXX Figure out what this should be.
122        auxv.push_back(auxv_t(M5_AT_FLAGS, 0));
123        //The entry point to the program
124        auxv.push_back(auxv_t(M5_AT_ENTRY, objFile->entryPoint()));
125        //Different user and group IDs
126        auxv.push_back(auxv_t(M5_AT_UID, uid()));
127        auxv.push_back(auxv_t(M5_AT_EUID, euid()));
128        auxv.push_back(auxv_t(M5_AT_GID, gid()));
129        auxv.push_back(auxv_t(M5_AT_EGID, egid()));
130        //Whether to enable "secure mode" in the executable
131        auxv.push_back(auxv_t(M5_AT_SECURE, 0));
132        //The filename of the program
133        auxv.push_back(auxv_t(M5_AT_EXECFN, 0));
134        //The string "v51" with unknown meaning
135        auxv.push_back(auxv_t(M5_AT_PLATFORM, 0));
136    }
137
138    //Figure out how big the initial stack nedes to be
139
140    // A sentry NULL void pointer at the top of the stack.
141    int sentry_size = intSize;
142
143    string platform = "v51";
144    int platform_size = platform.size() + 1;
145
146    // The aux vectors are put on the stack in two groups. The first group are
147    // the vectors that are generated as the elf is loaded. The second group
148    // are the ones that were computed ahead of time and include the platform
149    // string.
150    int aux_data_size = filename.size() + 1;
151
152    int env_data_size = 0;
153    for (int i = 0; i < envp.size(); ++i) {
154        env_data_size += envp[i].size() + 1;
155    }
156    int arg_data_size = 0;
157    for (int i = 0; i < argv.size(); ++i) {
158        arg_data_size += argv[i].size() + 1;
159    }
160
161    int info_block_size =
162        sentry_size + env_data_size + arg_data_size +
163        aux_data_size + platform_size;
164
165    //Each auxilliary vector is two 4 byte words
166    int aux_array_size = intSize * 2 * (auxv.size() + 1);
167
168    int envp_array_size = intSize * (envp.size() + 1);
169    int argv_array_size = intSize * (argv.size() + 1);
170
171    int argc_size = intSize;
172
173    //Figure out the size of the contents of the actual initial frame
174    int frame_size =
175        info_block_size +
176        aux_array_size +
177        envp_array_size +
178        argv_array_size +
179        argc_size;
180
181    //There needs to be padding after the auxiliary vector data so that the
182    //very bottom of the stack is aligned properly.
183    int partial_size = frame_size;
184    int aligned_partial_size = roundUp(partial_size, align);
185    int aux_padding = aligned_partial_size - partial_size;
186
187    int space_needed = frame_size + aux_padding;
188
189    memState->stackMin = memState->stackBase - space_needed;
190    memState->stackMin = roundDown(memState->stackMin, align);
191    memState->stackSize = memState->stackBase - memState->stackMin;
192
193    // map memory
194    allocateMem(roundDown(memState->stackMin, pageSize),
195                roundUp(memState->stackSize, pageSize));
196
197    // map out initial stack contents
198    uint32_t sentry_base = memState->stackBase - sentry_size;
199    uint32_t aux_data_base = sentry_base - aux_data_size;
200    uint32_t env_data_base = aux_data_base - env_data_size;
201    uint32_t arg_data_base = env_data_base - arg_data_size;
202    uint32_t platform_base = arg_data_base - platform_size;
203    uint32_t auxv_array_base = platform_base - aux_array_size - aux_padding;
204    uint32_t envp_array_base = auxv_array_base - envp_array_size;
205    uint32_t argv_array_base = envp_array_base - argv_array_size;
206    uint32_t argc_base = argv_array_base - argc_size;
207
208    DPRINTF(Stack, "The addresses of items on the initial stack:\n");
209    DPRINTF(Stack, "0x%x - aux data\n", aux_data_base);
210    DPRINTF(Stack, "0x%x - env data\n", env_data_base);
211    DPRINTF(Stack, "0x%x - arg data\n", arg_data_base);
212    DPRINTF(Stack, "0x%x - platform base\n", platform_base);
213    DPRINTF(Stack, "0x%x - auxv array\n", auxv_array_base);
214    DPRINTF(Stack, "0x%x - envp array\n", envp_array_base);
215    DPRINTF(Stack, "0x%x - argv array\n", argv_array_base);
216    DPRINTF(Stack, "0x%x - argc \n", argc_base);
217    DPRINTF(Stack, "0x%x - stack min\n", memState->stackMin);
218
219    // write contents to stack
220
221    // figure out argc
222    uint32_t argc = argv.size();
223    uint32_t guestArgc = PowerISA::htog(argc);
224
225    //Write out the sentry void *
226    uint32_t sentry_NULL = 0;
227    initVirtMem.writeBlob(sentry_base,
228            (uint8_t*)&sentry_NULL, sentry_size);
229
230    //Fix up the aux vectors which point to other data
231    for (int i = auxv.size() - 1; i >= 0; i--) {
232        if (auxv[i].a_type == M5_AT_PLATFORM) {
233            auxv[i].a_val = platform_base;
234            initVirtMem.writeString(platform_base, platform.c_str());
235        } else if (auxv[i].a_type == M5_AT_EXECFN) {
236            auxv[i].a_val = aux_data_base;
237            initVirtMem.writeString(aux_data_base, filename.c_str());
238        }
239    }
240
241    //Copy the aux stuff
242    for (int x = 0; x < auxv.size(); x++)
243    {
244        initVirtMem.writeBlob(auxv_array_base + x * 2 * intSize,
245                (uint8_t*)&(auxv[x].a_type), intSize);
246        initVirtMem.writeBlob(auxv_array_base + (x * 2 + 1) * intSize,
247                (uint8_t*)&(auxv[x].a_val), intSize);
248    }
249    //Write out the terminating zeroed auxilliary vector
250    const uint64_t zero = 0;
251    initVirtMem.writeBlob(auxv_array_base + 2 * intSize * auxv.size(),
252            (uint8_t*)&zero, 2 * intSize);
253
254    copyStringArray(envp, envp_array_base, env_data_base, initVirtMem);
255    copyStringArray(argv, argv_array_base, arg_data_base, initVirtMem);
256
257    initVirtMem.writeBlob(argc_base, (uint8_t*)&guestArgc, intSize);
258
259    ThreadContext *tc = system->getThreadContext(contextIds[0]);
260
261    //Set the stack pointer register
262    tc->setIntReg(StackPointerReg, memState->stackMin);
263
264    tc->pcState(getStartPC());
265
266    //Align the "stack_min" to a page boundary.
267    memState->stackMin = roundDown(memState->stackMin, pageSize);
268}
269
270PowerISA::IntReg
271PowerProcess::getSyscallArg(ThreadContext *tc, int &i)
272{
273    assert(i < 5);
274    return tc->readIntReg(ArgumentReg0 + i++);
275}
276
277void
278PowerProcess::setSyscallArg(ThreadContext *tc, int i, PowerISA::IntReg val)
279{
280    assert(i < 5);
281    tc->setIntReg(ArgumentReg0 + i, val);
282}
283
284void
285PowerProcess::setSyscallReturn(ThreadContext *tc, SyscallReturn sysret)
286{
287    Cr cr = tc->readIntReg(INTREG_CR);
288    if (sysret.successful()) {
289        cr.cr0.so = 0;
290    } else {
291        cr.cr0.so = 1;
292    }
293    tc->setIntReg(INTREG_CR, cr);
294    tc->setIntReg(ReturnValueReg, sysret.encodedValue());
295}
296