Map kernel high

Very important to give qemu memory through PHYSTOP :(

1 files changed, 19 insertions, 3 deletions

diff --git a/kalloc.c b/kalloc.c
index bf1616a..83ed7e8 100644
--- a/kalloc.c
+++ b/kalloc.c
@@ -5,6 +5,7 @@
 #include "types.h"
 #include "defs.h"
 #include "param.h"
+#include "memlayout.h"
 #include "mmu.h"
 #include "spinlock.h"
 
@@ -18,6 +19,20 @@ struct {
 } kmem;
 
 extern char end[]; // first address after kernel loaded from ELF file
+char *newend;
+
+// simple page allocator to get off the ground during boot
+char *
+pgalloc(void)
+{
+  if (newend == 0)
+    newend = end;
+
+  void *p = (void*)PGROUNDUP((uint)newend);
+  memset(p, 0, PGSIZE);
+  newend = newend + PGSIZE;
+  return p;
+}
 
 // Initialize free list of physical pages.
 void
@@ -26,8 +41,8 @@ kinit(void)
   char *p;
 
   initlock(&kmem.lock, "kmem");
-  p = (char*)PGROUNDUP((uint)end);
-  for(; p + PGSIZE <= (char*)PHYSTOP; p += PGSIZE)
+  p = (char*)PGROUNDUP((uint)newend);
+  for(; p + PGSIZE <= (char*)p2v(PHYSTOP); p += PGSIZE)
     kfree(p);
 }
 
@@ -41,7 +56,7 @@ kfree(char *v)
 {
   struct run *r;
 
-  if((uint)v % PGSIZE || v < end || (uint)v >= PHYSTOP) 
+  if((uint)v % PGSIZE || v < end || v2p(v) >= PHYSTOP) 
     panic("kfree");
 
   // Fill with junk to catch dangling refs.
@@ -67,6 +82,7 @@ kalloc(void)
   if(r)
     kmem.freelist = r->next;
   release(&kmem.lock);
+  cprintf("kalloc: 0x%x\n", r);
   return (char*)r;
 }