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#include "pk.h"
#include "vm.h"
#include "elf.h"
void run_loaded_program(struct mainvars* args)
{
if (current.is_supervisor)
panic("pk can't run kernel binaries; try using bbl instead");
uintptr_t kernel_stack_top = pk_vm_init();
extern char trap_entry;
write_csr(stvec, &trap_entry);
write_csr(sscratch, 0);
// enter supervisor mode
asm volatile("la t0, 1f; csrw mepc, t0; eret; 1:" ::: "t0");
// copy phdrs to user stack
size_t stack_top = current.stack_top - current.phdr_size;
memcpy((void*)stack_top, (void*)current.phdr, current.phdr_size);
current.phdr = stack_top;
// copy argv to user stack
for (size_t i = 0; i < args->argc; i++) {
size_t len = strlen((char*)(uintptr_t)args->argv[i])+1;
stack_top -= len;
memcpy((void*)stack_top, (void*)(uintptr_t)args->argv[i], len);
args->argv[i] = stack_top;
}
stack_top &= -sizeof(void*);
struct {
long key;
long value;
} aux[] = {
{AT_ENTRY, current.entry},
{AT_PHNUM, current.phnum},
{AT_PHENT, current.phent},
{AT_PHDR, current.phdr},
{AT_PAGESZ, RISCV_PGSIZE},
{AT_SECURE, 0},
{AT_RANDOM, stack_top},
{AT_NULL, 0}
};
// place argc, argv, envp, auxp on stack
#define PUSH_ARG(type, value) do { \
*((type*)sp) = value; \
sp += sizeof(type); \
} while (0)
#define STACK_INIT(type) do { \
unsigned naux = sizeof(aux)/sizeof(aux[0]); \
stack_top -= (1 + args->argc + 1 + 1 + 2*naux) * sizeof(type); \
stack_top &= -16; \
long sp = stack_top; \
PUSH_ARG(type, args->argc); \
for (unsigned i = 0; i < args->argc; i++) \
PUSH_ARG(type, args->argv[i]); \
PUSH_ARG(type, 0); /* argv[argc] = NULL */ \
PUSH_ARG(type, 0); /* envp[0] = NULL */ \
for (unsigned i = 0; i < naux; i++) { \
PUSH_ARG(type, aux[i].key); \
PUSH_ARG(type, aux[i].value); \
} \
} while (0)
if (current.elf64)
STACK_INIT(uint64_t);
else
STACK_INIT(uint32_t);
if (current.t0) // start timer if so requested
current.t0 = rdcycle();
if (uarch_counters_enabled) { // start tracking the uarch counters if requested
size_t i = 0;
#define READ_CTR_INIT(name) do { \
while (i >= NUM_COUNTERS) ; \
long csr = read_csr(name); \
uarch_counters[i++] = csr; \
} while (0)
READ_CTR_INIT(cycle); READ_CTR_INIT(instret);
READ_CTR_INIT(uarch0); READ_CTR_INIT(uarch1); READ_CTR_INIT(uarch2);
READ_CTR_INIT(uarch3); READ_CTR_INIT(uarch4); READ_CTR_INIT(uarch5);
READ_CTR_INIT(uarch6); READ_CTR_INIT(uarch7); READ_CTR_INIT(uarch8);
READ_CTR_INIT(uarch9); READ_CTR_INIT(uarch10); READ_CTR_INIT(uarch11);
READ_CTR_INIT(uarch12); READ_CTR_INIT(uarch13); READ_CTR_INIT(uarch14);
READ_CTR_INIT(uarch15);
#undef READ_CTR_INIT
}
trapframe_t tf;
init_tf(&tf, current.entry, stack_top, current.elf64);
__clear_cache(0, 0);
write_csr(sscratch, kernel_stack_top);
start_user(&tf);
}
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