growproc -> vmap::sbrk

26e69730 · Silas Boyd-Wickizer · 9298a90d · 26e69730 · 26e69730 · 26e69730
--- a/include/vm.hh
+++ b/include/vm.hh
@@ -86,6 +86,8 @@ struct vmap {

  int pagefault(uptr va, u32 err);
  int copyout(uptr va, void *p, u64 len);
+  int sbrk(int n);
+
  NEW_DELETE_OPS(vmap)

  uptr brk_;                    // Top of heap

--- a/kernel/proc.cc
+++ b/kernel/proc.cc
@@ -275,84 +275,6 @@ initproc(void)
    panic("pinit");
 }

-// Grow/shrink current process's memory by n bytes.
-// Growing may allocate vmas and physical memory,
-// but avoids interfering with any existing vma.
-// Assumes vmas around proc->brk are part of the growable heap.
-// Shrinking just decreases proc->brk; doesn't deallocate.
-// Return 0 on success, -1 on failure.
-int
-growproc(int n)
-{
-  struct vmap *m = myproc()->vmap;
-  auto curbrk = m->brk_;
-
-  if(n < 0 && 0 - n <= curbrk){
-    m->brk_ += n;
-    return 0;
-  }
-
-  if(n < 0 || n > USERTOP || curbrk + n > USERTOP)
-    return -1;
-
-  // look one page ahead, to check if the newly allocated region would
-  // abut the next-higher vma? we can't allow that, since then a future
-  // sbrk() would start to use the next region (e.g. the stack).
-  uptr newstart = PGROUNDUP(curbrk);
-  s64 newn = PGROUNDUP(n + curbrk - newstart);
-#if VM_CRANGE
-  range *prev = 0;
-  auto span = m->cr.search_lock(newstart, newn + PGSIZE);
-#endif
-#if VM_RADIX
-  auto span = m->rx.search_lock(newstart, newn + PGSIZE);
-#endif
-  for (auto r: span) {
-    vma *e = (vma*) r;
-
-    if (e->vma_start <= newstart) {
-      if (e->vma_end >= newstart + newn) {
-        m->brk_ += n;
-        return 0;
-      }
-
-      newn -= e->vma_end - newstart;
-      newstart = e->vma_end;
-#if VM_CRANGE
-      prev = e;
-#endif
-    } else {
-      cprintf("growproc: overlap with existing mapping; brk %lx n %d\n",
-              curbrk, n);
-      return -1;
-    }
-  }
-
-  vmnode *vmn = new vmnode(newn / PGSIZE);
-  if(vmn == 0){
-    cprintf("growproc: vmn_allocpg failed\n");
-    return -1;
-  }
-
-  vma *repl = new vma(m, newstart, newstart+newn, PRIVATE, vmn);
-  if (!repl) {
-    cprintf("growproc: out of vma\n");
-    delete vmn;
-    return -1;
-  }
-
-#if VM_CRANGE
-  span.replace(prev, repl);
-#endif
-
-#if VM_RADIX
-  span.replace(newstart, newn, repl);
-#endif
-
-  m->brk_ += n;
-  return 0;
-}
-
 // Kill the process with the given pid.
 // Process won't exit until it returns
 // to user space (see trap in trap.c).

--- a/kernel/sysproc.cc
+++ b/kernel/sysproc.cc
@@ -47,7 +47,7 @@ sys_sbrk(int n)
  uptr addr;

  addr = myproc()->vmap->brk_;
-  if(growproc(n) < 0)
+  if(myproc()->vmap->sbrk(n) < 0)
    return -1;
  return addr;
 }

--- a/kernel/vm.cc
+++ b/kernel/vm.cc
@@ -579,3 +579,80 @@ vmap::copyout(uptr va, void *p, u64 len)
  }
  return 0;
 }
+
+// Grow/shrink current process's memory by n bytes.
+// Growing may allocate vmas and physical memory,
+// but avoids interfering with any existing vma.
+// Assumes vmas around proc->brk are part of the growable heap.
+// Shrinking just decreases proc->brk; doesn't deallocate.
+// Return 0 on success, -1 on failure.
+int
+vmap::sbrk(int n)
+{
+  auto curbrk = brk_;
+
+  if(n < 0 && 0 - n <= curbrk){
+    brk_ += n;
+    return 0;
+  }
+
+  if(n < 0 || n > USERTOP || curbrk + n > USERTOP)
+    return -1;
+
+  // look one page ahead, to check if the newly allocated region would
+  // abut the next-higher vma? we can't allow that, since then a future
+  // sbrk() would start to use the next region (e.g. the stack).
+  uptr newstart = PGROUNDUP(curbrk);
+  s64 newn = PGROUNDUP(n + curbrk - newstart);
+#if VM_CRANGE
+  range *prev = 0;
+  auto span = cr.search_lock(newstart, newn + PGSIZE);
+#endif
+#if VM_RADIX
+  auto span = rx.search_lock(newstart, newn + PGSIZE);
+#endif
+  for (auto r: span) {
+    vma *e = (vma*) r;
+
+    if (e->vma_start <= newstart) {
+      if (e->vma_end >= newstart + newn) {
+        brk_ += n;
+        return 0;
+      }
+
+      newn -= e->vma_end - newstart;
+      newstart = e->vma_end;
+#if VM_CRANGE
+      prev = e;
+#endif
+    } else {
+      cprintf("growproc: overlap with existing mapping; brk %lx n %d\n",
+              curbrk, n);
+      return -1;
+    }
+  }
+
+  vmnode *vmn = new vmnode(newn / PGSIZE);
+  if(vmn == 0){
+    cprintf("growproc: vmn_allocpg failed\n");
+    return -1;
+  }
+
+  vma *repl = new vma(this, newstart, newstart+newn, PRIVATE, vmn);
+  if (!repl) {
+    cprintf("growproc: out of vma\n");
+    delete vmn;
+    return -1;
+  }
+
+#if VM_CRANGE
+  span.replace(prev, repl);
+#endif
+
+#if VM_RADIX
+  span.replace(newstart, newn, repl);
+#endif
+
+  brk_ += n;
+  return 0;
+}