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ARM: Set up the initial stack frame to match a recent Linux.

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This commit is contained in:
Gabe Black 2009-07-27 00:52:31 -07:00
parent ebc2897673
commit b8bf34be05
1 changed files with 203 additions and 37 deletions
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240
src/arch/arm/process.cc
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@ -46,7 +46,7 @@ using namespace ArmISA;
ArmLiveProcess::ArmLiveProcess(LiveProcessParams *params, ObjectFile *objFile)
: LiveProcess(params, objFile)
{
stack_base = 0xc0000000L;
stack_base = 0xbf000000L;
// Set pointer for next thread stack. Reserve 8M for main stack.
next_thread_stack_base = stack_base - (8 * 1024 * 1024);
@ -88,73 +88,239 @@ ArmLiveProcess::copyStringArray32(std::vector<std::string> &strings,
void
ArmLiveProcess::argsInit(int intSize, int pageSize)
{
typedef AuxVector<uint32_t> auxv_t;
std::vector<auxv_t> auxv;
string filename;
if (argv.size() < 1)
filename = "";
else
filename = argv[0];
//We want 16 byte alignment
uint64_t align = 16;
// Overloaded argsInit so that we can fine-tune for ARM architecture
Process::startup();
// load object file into target memory
objFile->loadSections(initVirtMem);
// Calculate how much space we need for arg & env arrays.
int argv_array_size = intSize * (argv.size() + 1);
int envp_array_size = intSize * (envp.size() + 1);
int arg_data_size = 0;
for (int i = 0; i < argv.size(); ++i) {
arg_data_size += argv[i].size() + 1;
enum ArmCpuFeature {
Arm_Swp = 1 << 0,
Arm_Half = 1 << 1,
Arm_Thumb = 1 << 2,
Arm_26Bit = 1 << 3,
Arm_FastMult = 1 << 4,
Arm_Fpa = 1 << 5,
Arm_Vfp = 1 << 6,
Arm_Edsp = 1 << 7,
Arm_Java = 1 << 8,
Arm_Iwmmxt = 1 << 9,
Arm_Crunch = 1 << 10
};
//Setup the auxilliary vectors. These will already have endian conversion.
//Auxilliary vectors are loaded only for elf formatted executables.
ElfObject * elfObject = dynamic_cast<ElfObject *>(objFile);
if (elfObject) {
uint32_t features =
Arm_Swp |
Arm_Half |
Arm_Thumb |
// Arm_26Bit |
Arm_FastMult |
// Arm_Fpa |
Arm_Vfp |
Arm_Edsp |
Arm_Java |
// Arm_Iwmmxt |
// Arm_Crunch |
0;
//Bits which describe the system hardware capabilities
//XXX Figure out what these should be
auxv.push_back(auxv_t(M5_AT_HWCAP, features));
//The system page size
auxv.push_back(auxv_t(M5_AT_PAGESZ, ArmISA::VMPageSize));
//Frequency at which times() increments
auxv.push_back(auxv_t(M5_AT_CLKTCK, 0x64));
// For statically linked executables, this is the virtual address of the
// program header tables if they appear in the executable image
auxv.push_back(auxv_t(M5_AT_PHDR, elfObject->programHeaderTable()));
// This is the size of a program header entry from the elf file.
auxv.push_back(auxv_t(M5_AT_PHENT, elfObject->programHeaderSize()));
// This is the number of program headers from the original elf file.
auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount()));
//This is the address of the elf "interpreter", It should be set
//to 0 for regular executables. It should be something else
//(not sure what) for dynamic libraries.
auxv.push_back(auxv_t(M5_AT_BASE, 0));
//XXX Figure out what this should be.
auxv.push_back(auxv_t(M5_AT_FLAGS, 0));
//The entry point to the program
auxv.push_back(auxv_t(M5_AT_ENTRY, objFile->entryPoint()));
//Different user and group IDs
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));
//The filename of the program
auxv.push_back(auxv_t(M5_AT_EXECFN, 0));
//The string "v51" with unknown meaning
auxv.push_back(auxv_t(M5_AT_PLATFORM, 0));
}
//Figure out how big the initial stack nedes to be
// A sentry NULL void pointer at the top of the stack.
int sentry_size = intSize;
string platform = "v51";
int platform_size = platform.size() + 1;
// The aux vectors are put on the stack in two groups. The first group are
// the vectors that are generated as the elf is loaded. The second group
// are the ones that were computed ahead of time and include the platform
// string.
int aux_data_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;
}
int space_needed =
argv_array_size + envp_array_size + arg_data_size + env_data_size;
if (space_needed < 16*1024)
space_needed = 16*1024;
int info_block_size =
sentry_size + env_data_size + arg_data_size +
aux_data_size + platform_size;
//Each auxilliary vector is two 4 byte 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;
//Figure out the size of the contents of the actual initial frame
int frame_size =
info_block_size +
aux_array_size +
envp_array_size +
argv_array_size +
argc_size;
//There needs to be padding after the auxiliary vector data so that the
//very bottom of the stack is aligned properly.
int partial_size = frame_size;
int aligned_partial_size = roundUp(partial_size, align);
int aux_padding = aligned_partial_size - partial_size;
int space_needed = frame_size + aux_padding;
// set bottom of stack
stack_min = stack_base - space_needed;
// align it
stack_min = roundDown(stack_min, pageSize);
stack_min = roundDown(stack_min, align);
stack_size = stack_base - stack_min;
// map memory
pTable->allocate(stack_min, roundUp(stack_size, pageSize));
pTable->allocate(roundDown(stack_min, pageSize),
roundUp(stack_size, pageSize));
// map out initial stack contents
Addr argv_array_base = stack_min + intSize; // room for argc
Addr envp_array_base = argv_array_base + argv_array_size;
Addr arg_data_base = envp_array_base + envp_array_size;
Addr env_data_base = arg_data_base + arg_data_size;
uint32_t sentry_base = stack_base - sentry_size;
uint32_t aux_data_base = sentry_base - aux_data_size;
uint32_t env_data_base = aux_data_base - env_data_size;
uint32_t arg_data_base = env_data_base - arg_data_size;
uint32_t platform_base = arg_data_base - platform_size;
uint32_t auxv_array_base = platform_base - aux_array_size - aux_padding;
uint32_t envp_array_base = auxv_array_base - envp_array_size;
uint32_t argv_array_base = envp_array_base - argv_array_size;
uint32_t argc_base = argv_array_base - argc_size;
DPRINTF(Stack, "The addresses of items on the initial stack:\n");
DPRINTF(Stack, "0x%x - aux data\n", aux_data_base);
DPRINTF(Stack, "0x%x - env data\n", env_data_base);
DPRINTF(Stack, "0x%x - arg data\n", arg_data_base);
DPRINTF(Stack, "0x%x - platform base\n", platform_base);
DPRINTF(Stack, "0x%x - auxv array\n", auxv_array_base);
DPRINTF(Stack, "0x%x - envp array\n", envp_array_base);
DPRINTF(Stack, "0x%x - argv array\n", argv_array_base);
DPRINTF(Stack, "0x%x - argc \n", argc_base);
DPRINTF(Stack, "0x%x - stack min\n", stack_min);
// write contents to stack
uint64_t argc = argv.size();
if (intSize == 8)
argc = htog((uint64_t)argc);
else if (intSize == 4)
argc = htog((uint32_t)argc);
else
panic("Unknown int size");
initVirtMem->writeBlob(stack_min, (uint8_t*)&argc, intSize);
// figure out argc
uint32_t argc = argv.size();
uint32_t guestArgc = ArmISA::htog(argc);
copyStringArray32(argv, argv_array_base, arg_data_base, initVirtMem);
copyStringArray32(envp, envp_array_base, env_data_base, initVirtMem);
//Write out the sentry void *
uint32_t sentry_NULL = 0;
initVirtMem->writeBlob(sentry_base,
(uint8_t*)&sentry_NULL, sentry_size);
/*
//uint8_t insns[] = {0xe5, 0x9f, 0x00, 0x08, 0xe1, 0xa0, 0xf0, 0x0e};
uint8_t insns[] = {0x08, 0x00, 0x9f, 0xe5, 0x0e, 0xf0, 0xa0, 0xe1};
//Fix up the aux vectors which point to other data
for (int i = auxv.size() - 1; i >= 0; i--) {
if (auxv[i].a_type == M5_AT_PLATFORM) {
auxv[i].a_val = platform_base;
initVirtMem->writeString(platform_base, platform.c_str());
} else if (auxv[i].a_type == M5_AT_EXECFN) {
auxv[i].a_val = aux_data_base;
initVirtMem->writeString(aux_data_base, filename.c_str());
}
}
initVirtMem->writeBlob(0xffff0fe0, insns, 8);
*/
//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 uint64_t zero = 0;
initVirtMem->writeBlob(auxv_array_base + 2 * intSize * auxv.size(),
(uint8_t*)&zero, 2 * 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);
ThreadContext *tc = system->getThreadContext(contextIds[0]);
tc->setIntReg(ArgumentReg1, argc);
tc->setIntReg(ArgumentReg2, argv_array_base);
//Set the stack pointer register
tc->setIntReg(StackPointerReg, stack_min);
//A pointer to a function to run when the program exits. We'll set this
//to zero explicitly to make sure this isn't used.
tc->setIntReg(ArgumentReg0, 0);
//Set argument regs 1 and 2 to argv[0] and envp[0] respectively
if (argv.size() > 0) {
tc->setIntReg(ArgumentReg1, arg_data_base + arg_data_size -
argv[argv.size() - 1].size() - 1);
} else {
tc->setIntReg(ArgumentReg1, 0);
}
if (envp.size() > 0) {
tc->setIntReg(ArgumentReg2, env_data_base + env_data_size -
envp[envp.size() - 1].size() - 1);
} else {
tc->setIntReg(ArgumentReg2, 0);
}
Addr prog_entry = objFile->entryPoint();
tc->setPC(prog_entry);
tc->setNextPC(prog_entry + sizeof(MachInst));
//Align the "stack_min" to a page boundary.
stack_min = roundDown(stack_min, pageSize);
}
ArmISA::IntReg