separate source into kernel/ user/ mkfs/

1 files changed, 0 insertions, 389 deletions

diff --git a/vm.c b/vm.c
deleted file mode 100644
index 0ea6bca..0000000
--- a/vm.c
+++ /dev/null
@@ -1,389 +0,0 @@
-#include "param.h"
-#include "types.h"
-#include "memlayout.h"
-#include "elf.h"
-#include "riscv.h"
-#include "defs.h"
-#include "fs.h"
-
-/*
- * the kernel's page table.
- */
-pagetable_t kernel_pagetable;
-
-extern char etext[];  // kernel.ld sets this to end of kernel code.
-
-extern char trampout[]; // trampoline.S
-
-/*
- * create a direct-map page table for the kernel and
- * turn on paging. called early, in supervisor mode.
- * the page allocator is already initialized.
- */
-void
-kvminit()
-{
-  kernel_pagetable = (pagetable_t) kalloc();
-  memset(kernel_pagetable, 0, PGSIZE);
-
-  // uart registers
-  mappages(kernel_pagetable, UART0, PGSIZE,
-           UART0, PTE_R | PTE_W);
-
-  // CLINT
-  mappages(kernel_pagetable, CLINT, 0x10000,
-           CLINT, PTE_R | PTE_W);
-
-  // PLIC
-  mappages(kernel_pagetable, PLIC, 0x4000000,
-           PLIC, PTE_R | PTE_W);
-
-  // map kernel text executable and read-only.
-  mappages(kernel_pagetable, KERNBASE, (uint64)etext-KERNBASE,
-           KERNBASE, PTE_R | PTE_X);
-
-  // map kernel data and the physical RAM we'll make use of.
-  mappages(kernel_pagetable, (uint64)etext, PHYSTOP-(uint64)etext,
-           (uint64)etext, PTE_R | PTE_W);
-
-  // map the qemu -initrd fs.img ramdisk
-  mappages(kernel_pagetable, RAMDISK, FSSIZE * BSIZE,
-           RAMDISK, PTE_R | PTE_W);
-
-  // map the trampoline for trap entry/exit to
-  // the highest virtual address in the kernel.
-  mappages(kernel_pagetable, TRAMPOLINE, PGSIZE,
-           (uint64)trampout, PTE_R | PTE_X);
-}
-
-// Switch h/w page table register to the kernel's page table,
-// and enable paging.
-void
-kvminithart()
-{
-  w_satp(MAKE_SATP(kernel_pagetable));
-}
-
-// Return the address of the PTE in page table pagetable
-// that corresponds to virtual address va.  If alloc!=0,
-// create any required page table pages.
-//
-// The risc-v Sv39 scheme has three levels of page table
-// pages. A page table page contains 512 64-bit PTEs.
-// A 64-bit virtual address is split into five fields:
-//   39..63 -- must be zero.
-//   30..38 -- 9 bits of level-2 index.
-//   21..39 -- 9 bits of level-1 index.
-//   12..20 -- 9 bits of level-0 index.
-//    0..12 -- 12 bits of byte offset within the page.
-static pte_t *
-walk(pagetable_t pagetable, uint64 va, int alloc)
-{
-  if(va >= MAXVA)
-    panic("walk");
-
-  for(int level = 2; level > 0; level--) {
-    pte_t *pte = &pagetable[PX(level, va)];
-    if(*pte & PTE_V) {
-      pagetable = (pagetable_t)PTE2PA(*pte);
-    } else {
-      if(!alloc || (pagetable = (pde_t*)kalloc()) == 0)
-        return 0;
-      memset(pagetable, 0, PGSIZE);
-      *pte = PA2PTE(pagetable) | PTE_V;
-    }
-  }
-  return &pagetable[PX(0, va)];
-}
-
-// Look up a virtual address, return the physical address,
-// Can only be used to look up user pages.
-// or 0 if not mapped.
-uint64
-walkaddr(pagetable_t pagetable, uint64 va)
-{
-  pte_t *pte;
-  uint64 pa;
-
-  pte = walk(pagetable, va, 0);
-  if(pte == 0)
-    return 0;
-  if((*pte & PTE_V) == 0)
-    return 0;
-  if((*pte & PTE_U) == 0)
-    return 0;
-  pa = PTE2PA(*pte);
-  return pa;
-}
-
-
-// Create PTEs for virtual addresses starting at va that refer to
-// physical addresses starting at pa. va and size might not
-// be page-aligned.
-void
-mappages(pagetable_t pagetable, uint64 va, uint64 size, uint64 pa, int perm)
-{
-  uint64 a, last;
-  pte_t *pte;
-
-  a = PGROUNDDOWN(va);
-  last = PGROUNDDOWN(va + size - 1);
-  for(;;){
-    if((pte = walk(pagetable, a, 1)) == 0)
-      panic("mappages: walk");
-    if(*pte & PTE_V)
-      panic("remap");
-    *pte = PA2PTE(pa) | perm | PTE_V;
-    if(a == last)
-      break;
-    a += PGSIZE;
-    pa += PGSIZE;
-  }
-}
-
-// Remove mappings from a page table. The mappings in
-// the given range must exist. Optionally free the
-// physical memory.
-void
-unmappages(pagetable_t pagetable, uint64 va, uint64 size, int do_free)
-{
-  uint64 a, last;
-  pte_t *pte;
-  uint64 pa;
-
-  a = PGROUNDDOWN(va);
-  last = PGROUNDDOWN(va + size - 1);
-  for(;;){
-    if((pte = walk(pagetable, a, 0)) == 0)
-      panic("unmappages: walk");
-    if((*pte & PTE_V) == 0){
-      printf("va=%p pte=%p\n", a, *pte);
-      panic("unmappages: not mapped");
-    }
-    if(PTE_FLAGS(*pte) == PTE_V)
-      panic("unmappages: not a leaf");
-    if(do_free){
-      pa = PTE2PA(*pte);
-      kfree((void*)pa);
-    }
-    *pte = 0;
-    if(a == last)
-      break;
-    a += PGSIZE;
-    pa += PGSIZE;
-  }
-}
-
-// create an empty user page table.
-pagetable_t
-uvmcreate()
-{
-  pagetable_t pagetable;
-  pagetable = (pagetable_t) kalloc();
-  if(pagetable == 0)
-    panic("uvmcreate: out of memory");
-  memset(pagetable, 0, PGSIZE);
-  return pagetable;
-}
-
-// Load the user initcode into address 0 of pagetable,
-// for the very first process.
-// sz must be less than a page.
-void
-uvminit(pagetable_t pagetable, uchar *src, uint sz)
-{
-  char *mem;
-
-  if(sz >= PGSIZE)
-    panic("inituvm: more than a page");
-  mem = kalloc();
-  memset(mem, 0, PGSIZE);
-  mappages(pagetable, 0, PGSIZE, (uint64)mem, PTE_W|PTE_R|PTE_X|PTE_U);
-  memmove(mem, src, sz);
-}
-
-// Allocate PTEs and physical memory to grow process from oldsz to
-// newsz, which need not be page aligned.  Returns new size or 0 on error.
-uint64
-uvmalloc(pagetable_t pagetable, uint64 oldsz, uint64 newsz)
-{
-  char *mem;
-  uint64 a;
-
-  if(newsz < oldsz)
-    return oldsz;
-
-  oldsz = PGROUNDUP(oldsz);
-  a = oldsz;
-  for(; a < newsz; a += PGSIZE){
-    mem = kalloc();
-    if(mem == 0){
-      uvmdealloc(pagetable, a, oldsz);
-      return 0;
-    }
-    memset(mem, 0, PGSIZE);
-    mappages(pagetable, a, PGSIZE, (uint64)mem, PTE_W|PTE_X|PTE_R|PTE_U);
-  }
-  return newsz;
-}
-
-// Deallocate user pages to bring the process size from oldsz to
-// newsz.  oldsz and newsz need not be page-aligned, nor does newsz
-// need to be less than oldsz.  oldsz can be larger than the actual
-// process size.  Returns the new process size.
-uint64
-uvmdealloc(pagetable_t pagetable, uint64 oldsz, uint64 newsz)
-{
-  if(newsz >= oldsz)
-    return oldsz;
-  unmappages(pagetable, newsz, oldsz - newsz, 1);
-  return newsz;
-}
-
-// Recursively free page table pages.
-// All leaf mappings must already have been removed.
-static void
-freewalk(pagetable_t pagetable)
-{
-  // there are 2^9 = 512 PTEs in a page table.
-  for(int i = 0; i < 512; i++){
-    pte_t pte = pagetable[i];
-    if((pte & PTE_V) && (pte & (PTE_R|PTE_W|PTE_X)) == 0){
-      // this PTE points to a lower-level page table.
-      uint64 child = PTE2PA(pte);
-      freewalk((pagetable_t)child);
-      pagetable[i] = 0;
-    } else if(pte & PTE_V){
-      panic("freewalk: leaf");
-    }
-  }
-  kfree((void*)pagetable);
-}
-
-// Free user memory pages,
-// then free page table pages.
-void
-uvmfree(pagetable_t pagetable, uint64 sz)
-{
-  unmappages(pagetable, 0, sz, 1);
-  freewalk(pagetable);
-}
-
-// Given a parent process's page table, copy
-// its memory into a child's page table.
-// Copies both the page table and the
-// physical memory.
-void
-uvmcopy(pagetable_t old, pagetable_t new, uint64 sz)
-{
-  pte_t *pte;
-  uint64 pa, i;
-  uint flags;
-  char *mem;
-
-  for(i = 0; i < sz; i += PGSIZE){
-    if((pte = walk(old, i, 0)) == 0)
-      panic("copyuvm: pte should exist");
-    if((*pte & PTE_V) == 0)
-      panic("copyuvm: page not present");
-    pa = PTE2PA(*pte);
-    flags = PTE_FLAGS(*pte);
-    if((mem = kalloc()) == 0)
-      panic("uvmcopy: kalloc failed");
-    memmove(mem, (char*)pa, PGSIZE);
-    mappages(new, i, PGSIZE, (uint64)mem, flags);
-  }
-}
-
-// Copy from kernel to user.
-// Copy len bytes from src to virtual address dstva in a given page table.
-// Return 0 on success, -1 on error.
-int
-copyout(pagetable_t pagetable, uint64 dstva, char *src, uint64 len)
-{
-  uint64 n, va0, pa0;
-
-  while(len > 0){
-    va0 = (uint)PGROUNDDOWN(dstva);
-    pa0 = walkaddr(pagetable, va0);
-    if(pa0 == 0)
-      return -1;
-    n = PGSIZE - (dstva - va0);
-    if(n > len)
-      n = len;
-    memmove((void *)(pa0 + (dstva - va0)), src, n);
-
-    len -= n;
-    src += n;
-    dstva = va0 + PGSIZE;
-  }
-  return 0;
-}
-
-// Copy from user to kernel.
-// Copy len bytes to dst from virtual address srcva in a given page table.
-// Return 0 on success, -1 on error.
-int
-copyin(pagetable_t pagetable, char *dst, uint64 srcva, uint64 len)
-{
-  uint64 n, va0, pa0;
-
-  while(len > 0){
-    va0 = (uint)PGROUNDDOWN(srcva);
-    pa0 = walkaddr(pagetable, va0);
-    if(pa0 == 0)
-      return -1;
-    n = PGSIZE - (srcva - va0);
-    if(n > len)
-      n = len;
-    memmove(dst, (void *)(pa0 + (srcva - va0)), n);
-
-    len -= n;
-    dst += n;
-    srcva = va0 + PGSIZE;
-  }
-  return 0;
-}
-
-// Copy a null-terminated string from user to kernel.
-// Copy bytes to dst from virtual address srcva in a given page table,
-// until a '\0', or max.
-// Return 0 on success, -1 on error.
-int
-copyinstr(pagetable_t pagetable, char *dst, uint64 srcva, uint64 max)
-{
-  uint64 n, va0, pa0;
-  int got_null = 0;
-
-  while(got_null == 0 && max > 0){
-    va0 = (uint)PGROUNDDOWN(srcva);
-    pa0 = walkaddr(pagetable, va0);
-    if(pa0 == 0)
-      return -1;
-    n = PGSIZE - (srcva - va0);
-    if(n > max)
-      n = max;
-
-    char *p = (char *) (pa0 + (srcva - va0));
-    while(n > 0){
-      if(*p == '\0'){
-        *dst = '\0';
-        got_null = 1;
-        break;
-      } else {
-        *dst = *p;
-      }
-      --n;
-      --max;
-      p++;
-      dst++;
-    }
-
-    srcva = va0 + PGSIZE;
-  }
-  if(got_null){
-    return 0;
-  } else {
-    return -1;
-  }
-}