separate source into kernel/ user/ mkfs/

1 files changed, 0 insertions, 184 deletions

diff --git a/trap.c b/trap.c
deleted file mode 100644
index 050a94d..0000000
--- a/trap.c
+++ /dev/null
@@ -1,184 +0,0 @@
-#include "types.h"
-#include "param.h"
-#include "memlayout.h"
-#include "riscv.h"
-#include "proc.h"
-#include "spinlock.h"
-#include "defs.h"
-
-struct spinlock tickslock;
-uint ticks;
-
-extern char trampout[], trampin[];
-
-// in kernelvec.S, calls kerneltrap().
-void kernelvec();
-
-extern int devintr();
-
-void
-trapinit(void)
-{
-  initlock(&tickslock, "time");
-}
-
-// set up to take exceptions and traps while in the kernel.
-void
-trapinithart(void)
-{
-  w_stvec((uint64)kernelvec);
-}
-
-//
-// handle an interrupt, exception, or system call from user space.
-// called from trampoline.S
-//
-void
-usertrap(void)
-{
-  int which_dev = 0;
-  
-  if((r_sstatus() & SSTATUS_SPP) != 0)
-    panic("usertrap: not from user mode");
-
-  // send interrupts and exceptions to kerneltrap(),
-  // since we're now in the kernel.
-  w_stvec((uint64)kernelvec);
-
-  struct proc *p = myproc();
-  
-  // save user program counter.
-  p->tf->epc = r_sepc();
-
-  intr_on();
-  
-  if(r_scause() == 8){
-    // system call
-
-    // sepc points to the ecall instruction,
-    // but we want to return to the next instruction.
-    p->tf->epc += 4;
-
-    syscall();
-  } else if((which_dev = devintr()) != 0){
-    // ok
-  } else {
-    printf("usertrap(): unexpected scause 0x%p pid=%d\n", r_scause(), p->pid);
-    printf("            sepc=%p stval=%p\n", r_sepc(), r_stval());
-    p->killed = 1;
-  }
-
-  if(p->killed)
-    exit();
-
-  // give up the CPU if this is a timer interrupt.
-  if(which_dev == 2)
-    yield();
-
-  usertrapret();
-}
-
-//
-// return to user space
-//
-void
-usertrapret(void)
-{
-  struct proc *p = myproc();
-
-  // turn off interrupts, since we're switching
-  // now from kerneltrap() to usertrap().
-  intr_off();
-
-  // send interrupts and exceptions to trampoline.S
-  w_stvec(TRAMPOLINE + (trampin - trampout));
-
-  // set up values that trampoline.S will need when
-  // the process next re-enters the kernel.
-  p->tf->kernel_satp = r_satp();
-  p->tf->kernel_sp = (uint64)p->kstack + PGSIZE;
-  p->tf->kernel_trap = (uint64)usertrap;
-  p->tf->hartid = r_tp();
-
-  // set up the registers that trampoline.S's sret will use
-  // to get to user space.
-  
-  // set S Previous Privilege mode to User.
-  unsigned long x = r_sstatus();
-  x &= ~SSTATUS_SPP; // clear SPP to 0 for user mode
-  x |= SSTATUS_SPIE; // enable interrupts in user mode
-  w_sstatus(x);
-
-  // set S Exception Program Counter to the saved user pc.
-  w_sepc(p->tf->epc);
-
-  // tell trampline.S the user page table to switch to.
-  uint64 satp = MAKE_SATP(p->pagetable);
-
-  // jump to trampoline.S at the top of memory, which 
-  // switches to the user page table, restores user registers,
-  // and switches to user mode with sret.
-  ((void (*)(uint64,uint64))TRAMPOLINE)(TRAMPOLINE - PGSIZE, satp);
-}
-
-// interrupts and exceptions from kernel code go here,
-// on whatever the current kernel stack is.
-// must be 4-byte aligned to fit in stvec.
-void 
-kerneltrap()
-{
-  uint64 sstatus = r_sstatus();
-  uint64 scause = r_scause();
-  
-  if((sstatus & SSTATUS_SPP) == 0)
-    panic("kerneltrap: not from supervisor mode");
-  if(intr_get() != 0)
-    panic("kerneltrap: interrupts enabled");
-
-  if(devintr() == 0){
-    printf("scause 0x%p\n", scause);
-    printf("sepc=%p stval=%p\n", r_sepc(), r_stval());
-    panic("kerneltrap");
-  }
-}
-
-// check if it's an external interrupt or software interrupt,
-// and handle it.
-// returns 2 if timer interrupt,
-// 1 if other device,
-// 0 if not recognized.
-int
-devintr()
-{
-  uint64 scause = r_scause();
-
-  if((scause & 0x8000000000000000L) &&
-     (scause & 0xff) == 9){
-    // supervisor external interrupt, via PLIC.
-    int irq = plic_claim();
-
-    if(irq == UART0_IRQ){
-      uartintr();
-    }
-
-    plic_complete(irq);
-    return 1;
-  } else if(scause == 0x8000000000000001){
-    // software interrupt from a machine-mode timer interrupt.
-
-    if(cpuid() == 0){
-      acquire(&tickslock);
-      ticks++;
-      wakeup(&ticks);
-      release(&tickslock);
-    }
-    
-    // acknowledge.
-    w_sip(r_sip() & ~2);
-
-    return 2;
-  } else {
-    return 0;
-  }
-}
-