pagetable lab initialized

kernel/vm.c

@@ -4,6 +4,8 @@
 #include "elf.h"
 #include "riscv.h"
 #include "defs.h"
+#include "spinlock.h"
+#include "proc.h"
 #include "fs.h"
 
 /*
@@ -30,8 +32,16 @@ kvmmake(void)
   // virtio mmio disk interface
   kvmmap(kpgtbl, VIRTIO0, VIRTIO0, PGSIZE, PTE_R | PTE_W);
 
+#ifdef LAB_NET
+  // PCI-E ECAM (configuration space), for pci.c
+  kvmmap(kpgtbl, 0x30000000L, 0x30000000L, 0x10000000, PTE_R | PTE_W);
+
+  // pci.c maps the e1000's registers here.
+  kvmmap(kpgtbl, 0x40000000L, 0x40000000L, 0x20000, PTE_R | PTE_W);
+#endif  
+
   // PLIC
-  kvmmap(kpgtbl, PLIC, PLIC, 0x400000, PTE_R | PTE_W);
+  kvmmap(kpgtbl, PLIC, PLIC, 0x4000000, PTE_R | PTE_W);
 
   // map kernel text executable and read-only.
   kvmmap(kpgtbl, KERNBASE, KERNBASE, (uint64)etext-KERNBASE, PTE_R | PTE_X);
@@ -92,6 +102,11 @@ walk(pagetable_t pagetable, uint64 va, int alloc)
     pte_t *pte = &pagetable[PX(level, va)];
     if(*pte & PTE_V) {
       pagetable = (pagetable_t)PTE2PA(*pte);
+#ifdef LAB_PGTBL
+      if(PTE_LEAF(*pte)) {
+        return pte;
+      }
+#endif
     } else {
       if(!alloc || (pagetable = (pde_t*)kalloc()) == 0)
         return 0;
@@ -125,6 +140,7 @@ walkaddr(pagetable_t pagetable, uint64 va)
   return pa;
 }
 
+
 // add a mapping to the kernel page table.
 // only used when booting.
 // does not flush TLB or enable paging.
@@ -179,15 +195,19 @@ uvmunmap(pagetable_t pagetable, uint64 va, uint64 npages, int do_free)
 {
   uint64 a;
   pte_t *pte;
+  int sz;
 
   if((va % PGSIZE) != 0)
     panic("uvmunmap: not aligned");
 
-  for(a = va; a < va + npages*PGSIZE; a += PGSIZE){
+  for(a = va; a < va + npages*PGSIZE; a += sz){
+    sz = PGSIZE;
     if((pte = walk(pagetable, a, 0)) == 0)
       panic("uvmunmap: walk");
-    if((*pte & PTE_V) == 0)
+    if((*pte & PTE_V) == 0) {
+      printf("va=%ld pte=%ld\n", a, *pte);
       panic("uvmunmap: not mapped");
+    }
     if(PTE_FLAGS(*pte) == PTE_V)
       panic("uvmunmap: not a leaf");
     if(do_free){
@@ -227,6 +247,7 @@ uvmfirst(pagetable_t pagetable, uchar *src, uint sz)
   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
@@ -234,19 +255,23 @@ uvmalloc(pagetable_t pagetable, uint64 oldsz, uint64 newsz, int xperm)
 {
   char *mem;
   uint64 a;
+  int sz;
 
   if(newsz < oldsz)
     return oldsz;
 
   oldsz = PGROUNDUP(oldsz);
-  for(a = oldsz; a < newsz; a += PGSIZE){
+  for(a = oldsz; a < newsz; a += sz){
+    sz = PGSIZE;
     mem = kalloc();
     if(mem == 0){
       uvmdealloc(pagetable, a, oldsz);
       return 0;
     }
-    memset(mem, 0, PGSIZE);
-    if(mappages(pagetable, a, PGSIZE, (uint64)mem, PTE_R|PTE_U|xperm) != 0){
+#ifndef LAB_SYSCALL
+    memset(mem, 0, sz);
+#endif
+    if(mappages(pagetable, a, sz, (uint64)mem, PTE_R|PTE_U|xperm) != 0){
       kfree(mem);
       uvmdealloc(pagetable, a, oldsz);
       return 0;
@@ -316,8 +341,11 @@ uvmcopy(pagetable_t old, pagetable_t new, uint64 sz)
   uint64 pa, i;
   uint flags;
   char *mem;
+  int szinc;
 
-  for(i = 0; i < sz; i += PGSIZE){
+  for(i = 0; i < sz; i += szinc){
+    szinc = PGSIZE;
+    szinc = PGSIZE;
     if((pte = walk(old, i, 0)) == 0)
       panic("uvmcopy: pte should exist");
     if((*pte & PTE_V) == 0)
@@ -363,13 +391,21 @@ copyout(pagetable_t pagetable, uint64 dstva, char *src, uint64 len)
 
   while(len > 0){
     va0 = PGROUNDDOWN(dstva);
-    if(va0 >= MAXVA)
+    if (va0 >= MAXVA)
       return -1;
-    pte = walk(pagetable, va0, 0);
-    if(pte == 0 || (*pte & PTE_V) == 0 || (*pte & PTE_U) == 0 ||
-       (*pte & PTE_W) == 0)
+    if((pte = walk(pagetable, va0, 0)) == 0) {
+      // printf("copyout: pte should exist 0x%x %d\n", dstva, len);
+      return -1;
+    }
+
+
+    // forbid copyout over read-only user text pages.
+    if((*pte & PTE_W) == 0)
+      return -1;
+    
+    pa0 = walkaddr(pagetable, va0);
+    if(pa0 == 0)
       return -1;
-    pa0 = PTE2PA(*pte);
     n = PGSIZE - (dstva - va0);
     if(n > len)
       n = len;
@@ -389,7 +425,7 @@ int
 copyin(pagetable_t pagetable, char *dst, uint64 srcva, uint64 len)
 {
   uint64 n, va0, pa0;
-
+  
   while(len > 0){
     va0 = PGROUNDDOWN(srcva);
     pa0 = walkaddr(pagetable, va0);
@@ -449,3 +485,20 @@ copyinstr(pagetable_t pagetable, char *dst, uint64 srcva, uint64 max)
     return -1;
   }
 }
+
+
+#ifdef LAB_PGTBL
+void
+vmprint(pagetable_t pagetable) {
+  // your code here
+}
+#endif
+
+
+
+#ifdef LAB_PGTBL
+pte_t*
+pgpte(pagetable_t pagetable, uint64 va) {
+  return walk(pagetable, va, 0);
+}
+#endif