src/arch/riscv/process.cc

   1 /*
   2  * Copyright (c) 2004-2005 The Regents of The University of Michigan
   3  * Copyright (c) 2016 The University of Virginia
   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
  30 #include "arch/riscv/process.hh"
  31
  32 #include <algorithm>
  33 #include <cstddef>
  34 #include <iostream>
  35 #include <iterator>
  36 #include <map>
  37 #include <string>
  38 #include <vector>
  39
  40 #include "arch/riscv/isa.hh"
  41 #include "arch/riscv/isa_traits.hh"
  42 #include "arch/riscv/registers.hh"
  43 #include "base/loader/elf_object.hh"
  44 #include "base/loader/object_file.hh"
  45 #include "base/logging.hh"
  46 #include "base/random.hh"
  47 #include "cpu/thread_context.hh"
  48 #include "debug/Stack.hh"
  49 #include "mem/page_table.hh"
  50 #include "params/Process.hh"
  51 #include "sim/aux_vector.hh"
  52 #include "sim/process.hh"
  53 #include "sim/process_impl.hh"
  54 #include "sim/syscall_return.hh"
  55 #include "sim/system.hh"
  56
  57 using namespace RiscvISA;
  58
  59 RiscvProcess::RiscvProcess(const ProcessParams &params,
  60         ::Loader::ObjectFile *objFile) :
  61         Process(params,
  62                 new EmulationPageTable(params.name, params.pid, PageBytes),
  63                 objFile)
  64 {
  65     fatal_if(params.useArchPT, "Arch page tables not implemented.");
  66 }
  67
  68 RiscvProcess64::RiscvProcess64(const ProcessParams &params,
  69         ::Loader::ObjectFile *objFile) :
  70         RiscvProcess(params, objFile)
  71 {
  72     const Addr stack_base = 0x7FFFFFFFFFFFFFFFL;
  73     const Addr max_stack_size = 8 * 1024 * 1024;
  74     const Addr next_thread_stack_base = stack_base - max_stack_size;
  75     const Addr brk_point = roundUp(image.maxAddr(), PageBytes);
  76     const Addr mmap_end = 0x4000000000000000L;
  77     memState = std::make_shared<MemState>(this, brk_point, stack_base,
  78             max_stack_size, next_thread_stack_base, mmap_end);
  79 }
  80
  81 RiscvProcess32::RiscvProcess32(const ProcessParams &params,
  82         ::Loader::ObjectFile *objFile) :
  83         RiscvProcess(params, objFile)
  84 {
  85     const Addr stack_base = 0x7FFFFFFF;
  86     const Addr max_stack_size = 8 * 1024 * 1024;
  87     const Addr next_thread_stack_base = stack_base - max_stack_size;
  88     const Addr brk_point = roundUp(image.maxAddr(), PageBytes);
  89     const Addr mmap_end = 0x40000000L;
  90     memState = std::make_shared<MemState>(this, brk_point, stack_base,
  91             max_stack_size, next_thread_stack_base, mmap_end);
  92 }
  93
  94 void
  95 RiscvProcess64::initState()
  96 {
  97     Process::initState();
  98
  99     argsInit<uint64_t>(PageBytes);
 100     for (ContextID ctx: contextIds)
 101         system->threads[ctx]->setMiscRegNoEffect(MISCREG_PRV, PRV_U);
 102 }
 103
 104 void
 105 RiscvProcess32::initState()
 106 {
 107     Process::initState();
 108
 109     argsInit<uint32_t>(PageBytes);
 110     for (ContextID ctx: contextIds) {
 111         auto *tc = system->threads[ctx];
 112         tc->setMiscRegNoEffect(MISCREG_PRV, PRV_U);
 113         PCState pc = tc->pcState();
 114         pc.rv32(true);
 115         tc->pcState(pc);
 116     }
 117 }
 118
 119 template<class IntType> void
 120 RiscvProcess::argsInit(int pageSize)
 121 {
 122     const int RandomBytes = 16;
 123     const int addrSize = sizeof(IntType);
 124
 125     auto *elfObject = dynamic_cast<::Loader::ElfObject*>(objFile);
 126     memState->setStackMin(memState->getStackBase());
 127
 128     // Determine stack size and populate auxv
 129     Addr stack_top = memState->getStackMin();
 130     stack_top -= RandomBytes;
 131     for (const std::string& arg: argv)
 132         stack_top -= arg.size() + 1;
 133     for (const std::string& env: envp)
 134         stack_top -= env.size() + 1;
 135     stack_top &= -addrSize;
 136
 137     std::vector<AuxVector<IntType>> auxv;
 138     if (elfObject != nullptr) {
 139         auxv.emplace_back(M5_AT_ENTRY, objFile->entryPoint());
 140         auxv.emplace_back(M5_AT_PHNUM, elfObject->programHeaderCount());
 141         auxv.emplace_back(M5_AT_PHENT, elfObject->programHeaderSize());
 142         auxv.emplace_back(M5_AT_PHDR, elfObject->programHeaderTable());
 143         auxv.emplace_back(M5_AT_PAGESZ, PageBytes);
 144         auxv.emplace_back(M5_AT_SECURE, 0);
 145         auxv.emplace_back(M5_AT_RANDOM, stack_top);
 146         auxv.emplace_back(M5_AT_NULL, 0);
 147     }
 148     stack_top -= (1 + argv.size()) * addrSize +
 149                    (1 + envp.size()) * addrSize +
 150                    addrSize + 2 * sizeof(IntType) * auxv.size();
 151     stack_top &= -2*addrSize;
 152     memState->setStackSize(memState->getStackBase() - stack_top);
 153     memState->mapRegion(roundDown(stack_top, pageSize),
 154                         roundUp(memState->getStackSize(), pageSize), "stack");
 155
 156     // Copy random bytes (for AT_RANDOM) to stack
 157     memState->setStackMin(memState->getStackMin() - RandomBytes);
 158     uint8_t at_random[RandomBytes];
 159     std::generate(std::begin(at_random), std::end(at_random),
 160                   [&]{ return random_mt.random(0, 0xFF); });
 161     initVirtMem->writeBlob(memState->getStackMin(), at_random, RandomBytes);
 162
 163     // Copy argv to stack
 164     std::vector<Addr> argPointers;
 165     for (const std::string& arg: argv) {
 166         memState->setStackMin(memState->getStackMin() - (arg.size() + 1));
 167         initVirtMem->writeString(memState->getStackMin(), arg.c_str());
 168         argPointers.push_back(memState->getStackMin());
 169         if (DTRACE(Stack)) {
 170             std::string wrote;
 171             initVirtMem->readString(wrote, argPointers.back());
 172             DPRINTFN("Wrote arg \"%s\" to address %p\n",
 173                     wrote, (void*)memState->getStackMin());
 174         }
 175     }
 176     argPointers.push_back(0);
 177
 178     // Copy envp to stack
 179     std::vector<Addr> envPointers;
 180     for (const std::string& env: envp) {
 181         memState->setStackMin(memState->getStackMin() - (env.size() + 1));
 182         initVirtMem->writeString(memState->getStackMin(), env.c_str());
 183         envPointers.push_back(memState->getStackMin());
 184         DPRINTF(Stack, "Wrote env \"%s\" to address %p\n",
 185                 env, (void*)memState->getStackMin());
 186     }
 187     envPointers.push_back(0);
 188
 189     // Align stack
 190     memState->setStackMin(memState->getStackMin() & -addrSize);
 191
 192     // Calculate bottom of stack
 193     memState->setStackMin(memState->getStackMin() -
 194             ((1 + argv.size()) * addrSize +
 195              (1 + envp.size()) * addrSize +
 196              addrSize + 2 * sizeof(IntType) * auxv.size()));
 197     memState->setStackMin(memState->getStackMin() & (-2 * addrSize));
 198     Addr sp = memState->getStackMin();
 199     const auto pushOntoStack =
 200         [this, &sp](IntType data) {
 201             initVirtMem->write(sp, data, GuestByteOrder);
 202             sp += sizeof(data);
 203         };
 204
 205     // Push argc and argv pointers onto stack
 206     IntType argc = argv.size();
 207     DPRINTF(Stack, "Wrote argc %d to address %#x\n", argc, sp);
 208     pushOntoStack(argc);
 209
 210     for (const Addr& argPointer: argPointers) {
 211         DPRINTF(Stack, "Wrote argv pointer %#x to address %#x\n",
 212                 argPointer, sp);
 213         pushOntoStack(argPointer);
 214     }
 215
 216     // Push env pointers onto stack
 217     for (const Addr& envPointer: envPointers) {
 218         DPRINTF(Stack, "Wrote envp pointer %#x to address %#x\n",
 219                 envPointer, sp);
 220         pushOntoStack(envPointer);
 221     }
 222
 223     // Push aux vector onto stack
 224     std::map<IntType, std::string> aux_keys = {
 225         {M5_AT_ENTRY, "M5_AT_ENTRY"},
 226         {M5_AT_PHNUM, "M5_AT_PHNUM"},
 227         {M5_AT_PHENT, "M5_AT_PHENT"},
 228         {M5_AT_PHDR, "M5_AT_PHDR"},
 229         {M5_AT_PAGESZ, "M5_AT_PAGESZ"},
 230         {M5_AT_SECURE, "M5_AT_SECURE"},
 231         {M5_AT_RANDOM, "M5_AT_RANDOM"},
 232         {M5_AT_NULL, "M5_AT_NULL"}
 233     };
 234     for (const auto &aux: auxv) {
 235         DPRINTF(Stack, "Wrote aux key %s to address %#x\n",
 236                 aux_keys[aux.type], sp);
 237         pushOntoStack(aux.type);
 238         DPRINTF(Stack, "Wrote aux value %x to address %#x\n", aux.val, sp);
 239         pushOntoStack(aux.val);
 240     }
 241
 242     ThreadContext *tc = system->threads[contextIds[0]];
 243     tc->setIntReg(StackPointerReg, memState->getStackMin());
 244     tc->pcState(getStartPC());
 245
 246     memState->setStackMin(roundDown(memState->getStackMin(), pageSize));
 247 }