process.cc revision 11851:824055fe6b30 
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/process_impl.hh"
44#include "sim/syscall_return.hh"
45#include "sim/system.hh"
46
47using namespace std;
48using namespace PowerISA;
49
50PowerProcess::PowerProcess(ProcessParams *params, ObjectFile *objFile)
51    : Process(params, objFile)
52{
53    stack_base = 0xbf000000L;
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, PageBytes);
61
62    // Set up region for mmaps. For now, start at bottom of kuseg space.
63    mmap_end = 0x70000000L;
64}
65
66void
67PowerProcess::initState()
68{
69    Process::initState();
70
71    argsInit(MachineBytes, PageBytes);
72}
73
74void
75PowerProcess::argsInit(int intSize, int pageSize)
76{
77    typedef AuxVector<uint32_t> auxv_t;
78    std::vector<auxv_t> auxv;
79
80    string filename;
81    if (argv.size() < 1)
82        filename = "";
83    else
84        filename = argv[0];
85
86    //We want 16 byte alignment
87    uint64_t align = 16;
88
89    // Patch the ld_bias for dynamic executables.
90    updateBias();
91
92    // load object file into target memory
93    objFile->loadSections(initVirtMem);
94
95    //Setup the auxilliary vectors. These will already have endian conversion.
96    //Auxilliary vectors are loaded only for elf formatted executables.
97    ElfObject * elfObject = dynamic_cast<ElfObject *>(objFile);
98    if (elfObject) {
99        uint32_t features = 0;
100
101        //Bits which describe the system hardware capabilities
102        //XXX Figure out what these should be
103        auxv.push_back(auxv_t(M5_AT_HWCAP, features));
104        //The system page size
105        auxv.push_back(auxv_t(M5_AT_PAGESZ, PowerISA::PageBytes));
106        //Frequency at which times() increments
107        auxv.push_back(auxv_t(M5_AT_CLKTCK, 0x64));
108        // For statically linked executables, this is the virtual address of the
109        // program header tables if they appear in the executable image
110        auxv.push_back(auxv_t(M5_AT_PHDR, elfObject->programHeaderTable()));
111        // This is the size of a program header entry from the elf file.
112        auxv.push_back(auxv_t(M5_AT_PHENT, elfObject->programHeaderSize()));
113        // This is the number of program headers from the original elf file.
114        auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount()));
115        // This is the base address of the ELF interpreter; it should be
116        // zero for static executables or contain the base address for
117        // dynamic executables.
118        auxv.push_back(auxv_t(M5_AT_BASE, getBias()));
119        //XXX Figure out what this should be.
120        auxv.push_back(auxv_t(M5_AT_FLAGS, 0));
121        //The entry point to the program
122        auxv.push_back(auxv_t(M5_AT_ENTRY, objFile->entryPoint()));
123        //Different user and group IDs
124        auxv.push_back(auxv_t(M5_AT_UID, uid()));
125        auxv.push_back(auxv_t(M5_AT_EUID, euid()));
126        auxv.push_back(auxv_t(M5_AT_GID, gid()));
127        auxv.push_back(auxv_t(M5_AT_EGID, egid()));
128        //Whether to enable "secure mode" in the executable
129        auxv.push_back(auxv_t(M5_AT_SECURE, 0));
130        //The filename of the program
131        auxv.push_back(auxv_t(M5_AT_EXECFN, 0));
132        //The string "v51" with unknown meaning
133        auxv.push_back(auxv_t(M5_AT_PLATFORM, 0));
134    }
135
136    //Figure out how big the initial stack nedes to be
137
138    // A sentry NULL void pointer at the top of the stack.
139    int sentry_size = intSize;
140
141    string platform = "v51";
142    int platform_size = platform.size() + 1;
143
144    // The aux vectors are put on the stack in two groups. The first group are
145    // the vectors that are generated as the elf is loaded. The second group
146    // are the ones that were computed ahead of time and include the platform
147    // string.
148    int aux_data_size = filename.size() + 1;
149
150    int env_data_size = 0;
151    for (int i = 0; i < envp.size(); ++i) {
152        env_data_size += envp[i].size() + 1;
153    }
154    int arg_data_size = 0;
155    for (int i = 0; i < argv.size(); ++i) {
156        arg_data_size += argv[i].size() + 1;
157    }
158
159    int info_block_size =
160        sentry_size + env_data_size + arg_data_size +
161        aux_data_size + platform_size;
162
163    //Each auxilliary vector is two 4 byte words
164    int aux_array_size = intSize * 2 * (auxv.size() + 1);
165
166    int envp_array_size = intSize * (envp.size() + 1);
167    int argv_array_size = intSize * (argv.size() + 1);
168
169    int argc_size = intSize;
170
171    //Figure out the size of the contents of the actual initial frame
172    int frame_size =
173        info_block_size +
174        aux_array_size +
175        envp_array_size +
176        argv_array_size +
177        argc_size;
178
179    //There needs to be padding after the auxiliary vector data so that the
180    //very bottom of the stack is aligned properly.
181    int partial_size = frame_size;
182    int aligned_partial_size = roundUp(partial_size, align);
183    int aux_padding = aligned_partial_size - partial_size;
184
185    int space_needed = frame_size + aux_padding;
186
187    stack_min = stack_base - space_needed;
188    stack_min = roundDown(stack_min, align);
189    stack_size = stack_base - stack_min;
190
191    // map memory
192    allocateMem(roundDown(stack_min, pageSize), roundUp(stack_size, pageSize));
193
194    // map out initial stack contents
195    uint32_t sentry_base = stack_base - sentry_size;
196    uint32_t aux_data_base = sentry_base - aux_data_size;
197    uint32_t env_data_base = aux_data_base - env_data_size;
198    uint32_t arg_data_base = env_data_base - arg_data_size;
199    uint32_t platform_base = arg_data_base - platform_size;
200    uint32_t auxv_array_base = platform_base - aux_array_size - aux_padding;
201    uint32_t envp_array_base = auxv_array_base - envp_array_size;
202    uint32_t argv_array_base = envp_array_base - argv_array_size;
203    uint32_t argc_base = argv_array_base - argc_size;
204
205    DPRINTF(Stack, "The addresses of items on the initial stack:\n");
206    DPRINTF(Stack, "0x%x - aux data\n", aux_data_base);
207    DPRINTF(Stack, "0x%x - env data\n", env_data_base);
208    DPRINTF(Stack, "0x%x - arg data\n", arg_data_base);
209    DPRINTF(Stack, "0x%x - platform base\n", platform_base);
210    DPRINTF(Stack, "0x%x - auxv array\n", auxv_array_base);
211    DPRINTF(Stack, "0x%x - envp array\n", envp_array_base);
212    DPRINTF(Stack, "0x%x - argv array\n", argv_array_base);
213    DPRINTF(Stack, "0x%x - argc \n", argc_base);
214    DPRINTF(Stack, "0x%x - stack min\n", stack_min);
215
216    // write contents to stack
217
218    // figure out argc
219    uint32_t argc = argv.size();
220    uint32_t guestArgc = PowerISA::htog(argc);
221
222    //Write out the sentry void *
223    uint32_t sentry_NULL = 0;
224    initVirtMem.writeBlob(sentry_base,
225            (uint8_t*)&sentry_NULL, sentry_size);
226
227    //Fix up the aux vectors which point to other data
228    for (int i = auxv.size() - 1; i >= 0; i--) {
229        if (auxv[i].a_type == M5_AT_PLATFORM) {
230            auxv[i].a_val = platform_base;
231            initVirtMem.writeString(platform_base, platform.c_str());
232        } else if (auxv[i].a_type == M5_AT_EXECFN) {
233            auxv[i].a_val = aux_data_base;
234            initVirtMem.writeString(aux_data_base, filename.c_str());
235        }
236    }
237
238    //Copy the aux stuff
239    for (int x = 0; x < auxv.size(); x++)
240    {
241        initVirtMem.writeBlob(auxv_array_base + x * 2 * intSize,
242                (uint8_t*)&(auxv[x].a_type), intSize);
243        initVirtMem.writeBlob(auxv_array_base + (x * 2 + 1) * intSize,
244                (uint8_t*)&(auxv[x].a_val), intSize);
245    }
246    //Write out the terminating zeroed auxilliary vector
247    const uint64_t zero = 0;
248    initVirtMem.writeBlob(auxv_array_base + 2 * intSize * auxv.size(),
249            (uint8_t*)&zero, 2 * intSize);
250
251    copyStringArray(envp, envp_array_base, env_data_base, initVirtMem);
252    copyStringArray(argv, argv_array_base, arg_data_base, initVirtMem);
253
254    initVirtMem.writeBlob(argc_base, (uint8_t*)&guestArgc, intSize);
255
256    ThreadContext *tc = system->getThreadContext(contextIds[0]);
257
258    //Set the stack pointer register
259    tc->setIntReg(StackPointerReg, stack_min);
260
261    tc->pcState(getStartPC());
262
263    //Align the "stack_min" to a page boundary.
264    stack_min = roundDown(stack_min, pageSize);
265}
266
267PowerISA::IntReg
268PowerProcess::getSyscallArg(ThreadContext *tc, int &i)
269{
270    assert(i < 5);
271    return tc->readIntReg(ArgumentReg0 + i++);
272}
273
274void
275PowerProcess::setSyscallArg(ThreadContext *tc, int i, PowerISA::IntReg val)
276{
277    assert(i < 5);
278    tc->setIntReg(ArgumentReg0 + i, val);
279}
280
281void
282PowerProcess::setSyscallReturn(ThreadContext *tc, SyscallReturn sysret)
283{
284    Cr cr = tc->readIntReg(INTREG_CR);
285    if (sysret.successful()) {
286        cr.cr0.so = 0;
287    } else {
288        cr.cr0.so = 1;
289    }
290    tc->setIntReg(INTREG_CR, cr);
291    tc->setIntReg(ReturnValueReg, sysret.encodedValue());
292}
293