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// See LICENSE for license details.
#include "pk.h"
#include "config.h"
#include "syscall.h"
#include "mmap.h"
static void handle_instruction_access_fault(trapframe_t *tf)
{
dump_tf(tf);
panic("Instruction access fault!");
}
static void handle_load_access_fault(trapframe_t *tf)
{
dump_tf(tf);
panic("Load access fault!");
}
static void handle_store_access_fault(trapframe_t *tf)
{
dump_tf(tf);
panic("Store/AMO access fault!");
}
static void handle_illegal_instruction(trapframe_t* tf)
{
dump_tf(tf);
panic("An illegal instruction was executed!");
}
static void handle_breakpoint(trapframe_t* tf)
{
dump_tf(tf);
panic("Breakpoint!");
}
static void handle_misaligned_fetch(trapframe_t* tf)
{
dump_tf(tf);
panic("Misaligned instruction access!");
}
static void handle_misaligned_load(trapframe_t* tf)
{
dump_tf(tf);
panic("Misaligned Load!");
}
static void handle_misaligned_store(trapframe_t* tf)
{
dump_tf(tf);
panic("Misaligned AMO!");
}
static void segfault(trapframe_t* tf, uintptr_t addr, const char* type)
{
dump_tf(tf);
const char* who = (tf->status & SSTATUS_SPP) ? "Kernel" : "User";
panic("%s %s segfault @ %p", who, type, addr);
}
static void handle_fault_fetch(trapframe_t* tf)
{
if (handle_page_fault(tf->badvaddr, PROT_EXEC) != 0)
segfault(tf, tf->badvaddr, "fetch");
}
static void handle_fault_load(trapframe_t* tf)
{
if (handle_page_fault(tf->badvaddr, PROT_READ) != 0)
segfault(tf, tf->badvaddr, "load");
}
static void handle_fault_store(trapframe_t* tf)
{
if (handle_page_fault(tf->badvaddr, PROT_WRITE) != 0)
segfault(tf, tf->badvaddr, "store");
}
static void handle_syscall(trapframe_t* tf)
{
tf->gpr[10] = do_syscall(tf->gpr[10], tf->gpr[11], tf->gpr[12], tf->gpr[13],
tf->gpr[14], tf->gpr[15], tf->gpr[17]);
tf->epc += 4;
}
static void handle_interrupt(trapframe_t* tf)
{
clear_csr(sip, SIP_SSIP);
}
void handle_trap(trapframe_t* tf)
{
if ((intptr_t)tf->cause < 0)
return handle_interrupt(tf);
typedef void (*trap_handler)(trapframe_t*);
const static trap_handler trap_handlers[] = {
[CAUSE_MISALIGNED_FETCH] = handle_misaligned_fetch,
[CAUSE_FETCH_ACCESS] = handle_instruction_access_fault,
[CAUSE_LOAD_ACCESS] = handle_load_access_fault,
[CAUSE_STORE_ACCESS] = handle_store_access_fault,
[CAUSE_FETCH_PAGE_FAULT] = handle_fault_fetch,
[CAUSE_ILLEGAL_INSTRUCTION] = handle_illegal_instruction,
[CAUSE_USER_ECALL] = handle_syscall,
[CAUSE_BREAKPOINT] = handle_breakpoint,
[CAUSE_MISALIGNED_LOAD] = handle_misaligned_load,
[CAUSE_MISALIGNED_STORE] = handle_misaligned_store,
[CAUSE_LOAD_PAGE_FAULT] = handle_fault_load,
[CAUSE_STORE_PAGE_FAULT] = handle_fault_store,
};
kassert(tf->cause < ARRAY_SIZE(trap_handlers) && trap_handlers[tf->cause]);
trap_handler f = (void*)pa2kva(trap_handlers[tf->cause]);
f(tf);
}
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