works, except no vma growing yet

d0347377 · Nickolai Zeldovich · 792497fa · d0347377 · d0347377 · d0347377
--- a/exec.c
+++ b/exec.c
@@ -67,7 +67,8 @@ exec(char *path, char **argv)
  ip = 0;

  // Allocate a vmnode for the heap.
-  if((vmn = vmn_allocpg(1)) == 0)
+  // XXX pre-allocate 32 pages..
+  if((vmn = vmn_allocpg(32)) == 0)
    goto bad;
  if(vmap_insert(vmap, vmn, brk) < 0)
    goto bad;
@@ -112,7 +113,7 @@ exec(char *path, char **argv)
  oldvmap = proc->vmap;
  proc->pgdir = pgdir;
  proc->vmap = vmap;
-  proc->brk = brk;
+  proc->brk = brk + 4;  // XXX so that brk-1 points within heap vma..
  proc->tf->eip = elf.entry;  // main
  proc->tf->esp = sp;
  switchuvm(proc);

--- a/proc.c
+++ b/proc.c
@@ -116,13 +116,19 @@ growproc(int n)
  uint brk = proc->brk;
  uint nbrk = brk + n;

-  /* XXX */
-  if(brk / PGSIZE != nbrk / PGSIZE) {
-    cprintf("cannot resize heap\n");
+  struct vma *vma = vmap_lookup(proc->vmap, brk-1);
+  if(vma == 0)
+    return -1;
+
+  if(nbrk > vma->va_end){
+    /* XXX */
+    release(&vma->lock);
+    cprintf("cannot resize heap: %d -> %d\n", brk, nbrk);
    return -1;
  }

  proc->brk = brk + n;
+  release(&vma->lock);
  switchuvm(proc);
  return 0;
 }

--- a/vm.c
+++ b/vm.c
@@ -185,7 +185,7 @@ switchuvm(struct proc *p)
 }

 struct {
-  struct vmnode n[128];
+  struct vmnode n[1024];
 } vmnodes;

 struct {