process.cc

来自「M5,一个功能强大的多处理器系统模拟器.很多针对处理器架构,性能的研究都使用它作」· CC 代码 · 共 508 行 · 第 1/2 页

        auxv.push_back(auxv_t(M5_AT_UID, uid()));
        auxv.push_back(auxv_t(M5_AT_EUID, euid()));
        auxv.push_back(auxv_t(M5_AT_GID, gid()));
        auxv.push_back(auxv_t(M5_AT_EGID, egid()));
        //Whether to enable "secure mode" in the executable
        auxv.push_back(auxv_t(M5_AT_SECURE, 0));
    }

    //Figure out how big the initial stack needs to be

    // The unaccounted for 8 byte 0 at the top of the stack
    int sentry_size = 8;

    //This is the name of the file which is present on the initial stack
    //It's purpose is to let the user space linker examine the original file.
    int file_name_size = filename.size() + 1;

    int env_data_size = 0;
    for (int i = 0; i < envp.size(); ++i) {
        env_data_size += envp[i].size() + 1;
    }
    int arg_data_size = 0;
    for (int i = 0; i < argv.size(); ++i) {
        arg_data_size += argv[i].size() + 1;
    }

    //The info_block.
    int base_info_block_size =
        sentry_size + file_name_size + env_data_size + arg_data_size;

    int info_block_size = roundUp(base_info_block_size, align);

    int info_block_padding = info_block_size - base_info_block_size;

    //Each auxilliary vector is two words
    int aux_array_size = intSize * 2 * (auxv.size() + 1);

    int envp_array_size = intSize * (envp.size() + 1);
    int argv_array_size = intSize * (argv.size() + 1);

    int argc_size = intSize;
    int window_save_size = intSize * 16;

    //Figure out the size of the contents of the actual initial frame
    int frame_size =
        aux_array_size +
        envp_array_size +
        argv_array_size +
        argc_size +
        window_save_size;

    //There needs to be padding after the auxiliary vector data so that the
    //very bottom of the stack is aligned properly.
    int aligned_partial_size = roundUp(frame_size, align);
    int aux_padding = aligned_partial_size - frame_size;

    int space_needed =
        info_block_size +
        aux_padding +
        frame_size;

    stack_min = stack_base - space_needed;
    stack_min = roundDown(stack_min, align);
    stack_size = stack_base - stack_min;

    // Allocate space for the stack
    pTable->allocate(roundDown(stack_min, pageSize),
                     roundUp(stack_size, pageSize));

    // map out initial stack contents
    IntType sentry_base = stack_base - sentry_size;
    IntType file_name_base = sentry_base - file_name_size;
    IntType env_data_base = file_name_base - env_data_size;
    IntType arg_data_base = env_data_base - arg_data_size;
    IntType auxv_array_base = arg_data_base -
        info_block_padding - aux_array_size - aux_padding;
    IntType envp_array_base = auxv_array_base - envp_array_size;
    IntType argv_array_base = envp_array_base - argv_array_size;
    IntType argc_base = argv_array_base - argc_size;
#if TRACING_ON
    IntType window_save_base = argc_base - window_save_size;
#endif

    DPRINTF(Sparc, "The addresses of items on the initial stack:\n");
    DPRINTF(Sparc, "%#x - sentry NULL\n", sentry_base);
    DPRINTF(Sparc, "filename = %s\n", filename);
    DPRINTF(Sparc, "%#x - file name\n", file_name_base);
    DPRINTF(Sparc, "%#x - env data\n", env_data_base);
    DPRINTF(Sparc, "%#x - arg data\n", arg_data_base);
    DPRINTF(Sparc, "%#x - auxv array\n", auxv_array_base);
    DPRINTF(Sparc, "%#x - envp array\n", envp_array_base);
    DPRINTF(Sparc, "%#x - argv array\n", argv_array_base);
    DPRINTF(Sparc, "%#x - argc \n", argc_base);
    DPRINTF(Sparc, "%#x - window save\n", window_save_base);
    DPRINTF(Sparc, "%#x - stack min\n", stack_min);

    assert(window_save_base == stack_min);

    // write contents to stack

    // figure out argc
    IntType argc = argv.size();
    IntType guestArgc = TheISA::htog(argc);

    //Write out the sentry void *
    uint64_t sentry_NULL = 0;
    initVirtMem->writeBlob(sentry_base,
            (uint8_t*)&sentry_NULL, sentry_size);

    //Write the file name
    initVirtMem->writeString(file_name_base, filename.c_str());

    //Copy the aux stuff
    for(int x = 0; x < auxv.size(); x++)
    {
        initVirtMem->writeBlob(auxv_array_base + x * 2 * intSize,
                (uint8_t*)&(auxv[x].a_type), intSize);
        initVirtMem->writeBlob(auxv_array_base + (x * 2 + 1) * intSize,
                (uint8_t*)&(auxv[x].a_val), intSize);
    }

    //Write out the terminating zeroed auxilliary vector
    const IntType zero = 0;
    initVirtMem->writeBlob(auxv_array_base + intSize * 2 * auxv.size(),
            (uint8_t*)&zero, intSize);
    initVirtMem->writeBlob(auxv_array_base + intSize * (2 * auxv.size() + 1),
            (uint8_t*)&zero, intSize);

    copyStringArray(envp, envp_array_base, env_data_base, initVirtMem);
    copyStringArray(argv, argv_array_base, arg_data_base, initVirtMem);

    initVirtMem->writeBlob(argc_base, (uint8_t*)&guestArgc, intSize);

    //Set up space for the trap handlers into the processes address space.
    //Since the stack grows down and there is reserved address space abov
    //it, we can put stuff above it and stay out of the way.
    fillStart = stack_base;
    spillStart = fillStart + sizeof(MachInst) * numFillInsts;

    //Set up the thread context to start running the process
    //assert(NumArgumentRegs >= 2);
    //threadContexts[0]->setIntReg(ArgumentReg[0], argc);
    //threadContexts[0]->setIntReg(ArgumentReg[1], argv_array_base);
    threadContexts[0]->setIntReg(StackPointerReg, stack_min - StackBias);

    // %g1 is a pointer to a function that should be run at exit. Since we
    // don't have anything like that, it should be set to 0.
    threadContexts[0]->setIntReg(1, 0);

    Addr prog_entry = objFile->entryPoint();
    threadContexts[0]->setPC(prog_entry);
    threadContexts[0]->setNextPC(prog_entry + sizeof(MachInst));
    threadContexts[0]->setNextNPC(prog_entry + (2 * sizeof(MachInst)));

    //Align the "stack_min" to a page boundary.
    stack_min = roundDown(stack_min, pageSize);

//    num_processes++;
}

void
Sparc64LiveProcess::argsInit(int intSize, int pageSize)
{
    SparcLiveProcess::argsInit<uint64_t>(pageSize);

    // Stuff the trap handlers into the process address space
    initVirtMem->writeBlob(fillStart,
            (uint8_t*)fillHandler64, sizeof(MachInst) * numFillInsts);
    initVirtMem->writeBlob(spillStart,
            (uint8_t*)spillHandler64, sizeof(MachInst) *  numSpillInsts);
}

void
Sparc32LiveProcess::argsInit(int intSize, int pageSize)
{
    SparcLiveProcess::argsInit<uint32_t>(pageSize);

    // Stuff the trap handlers into the process address space
    initVirtMem->writeBlob(fillStart,
            (uint8_t*)fillHandler32, sizeof(MachInst) * numFillInsts);
    initVirtMem->writeBlob(spillStart,
            (uint8_t*)spillHandler32, sizeof(MachInst) *  numSpillInsts);
}

void Sparc32LiveProcess::flushWindows(ThreadContext *tc)
{
    IntReg Cansave = tc->readIntReg(NumIntArchRegs + 3);
    IntReg Canrestore = tc->readIntReg(NumIntArchRegs + 4);
    IntReg Otherwin = tc->readIntReg(NumIntArchRegs + 6);
    MiscReg CWP = tc->readMiscReg(MISCREG_CWP);
    MiscReg origCWP = CWP;
    CWP = (CWP + Cansave + 2) % NWindows;
    while(NWindows - 2 - Cansave != 0)
    {
        if (Otherwin) {
            panic("Otherwin non-zero.\n");
        } else {
            tc->setMiscReg(MISCREG_CWP, CWP);
            //Do the stores
            IntReg sp = tc->readIntReg(StackPointerReg);
            for (int index = 16; index < 32; index++) {
                uint32_t regVal = tc->readIntReg(index);
                regVal = htog(regVal);
                if (!tc->getMemPort()->tryWriteBlob(
                        sp + (index - 16) * 4, (uint8_t *)&regVal, 4)) {
                    warn("Failed to save register to the stack when "
                            "flushing windows.\n");
                }
            }
            Canrestore--;
            Cansave++;
            CWP = (CWP + 1) % NWindows;
        }
    }
    tc->setIntReg(NumIntArchRegs + 3, Cansave);
    tc->setIntReg(NumIntArchRegs + 4, Canrestore);
    tc->setMiscReg(MISCREG_CWP, origCWP);
}

void Sparc64LiveProcess::flushWindows(ThreadContext *tc)
{
    IntReg Cansave = tc->readIntReg(NumIntArchRegs + 3);
    IntReg Canrestore = tc->readIntReg(NumIntArchRegs + 4);
    IntReg Otherwin = tc->readIntReg(NumIntArchRegs + 6);
    MiscReg CWP = tc->readMiscReg(MISCREG_CWP);
    MiscReg origCWP = CWP;
    CWP = (CWP + Cansave + 2) % NWindows;
    while(NWindows - 2 - Cansave != 0)
    {
        if (Otherwin) {
            panic("Otherwin non-zero.\n");
        } else {
            tc->setMiscReg(MISCREG_CWP, CWP);
            //Do the stores
            IntReg sp = tc->readIntReg(StackPointerReg);
            for (int index = 16; index < 32; index++) {
                IntReg regVal = tc->readIntReg(index);
                regVal = htog(regVal);
                if (!tc->getMemPort()->tryWriteBlob(
                        sp + 2047 + (index - 16) * 8, (uint8_t *)&regVal, 8)) {
                    warn("Failed to save register to the stack when "
                            "flushing windows.\n");
                }
            }
            Canrestore--;
            Cansave++;
            CWP = (CWP + 1) % NWindows;
        }
    }
    tc->setIntReg(NumIntArchRegs + 3, Cansave);
    tc->setIntReg(NumIntArchRegs + 4, Canrestore);
    tc->setMiscReg(MISCREG_CWP, origCWP);
}