some more reorg

ca7c3fca · Nickolai Zeldovich · eabc1d9c · ca7c3fca · ca7c3fca · ca7c3fca
--- a/exec.cc
+++ b/exec.cc
@@ -61,10 +61,10 @@ dosegment(uptr a0, u64 a1)
    int npg = (va_end - va_start) / PGSIZE;
    if (odp) {
-      if ((vmn = vmn_alloc(npg, ONDEMAND)) == 0)
+      if ((vmn = new vmnode(npg, ONDEMAND)) == 0)
        goto bad;
    } else {
-      if ((vmn = vmn_allocpg(npg)) == 0)
+      if ((vmn = new vmnode(npg)) == 0)
        goto bad;
    }
@@ -93,7 +93,7 @@ static void dostack(uptr a0, u64 a1)
  prof_start(dostack_prof);
    // Allocate a one-page stack at the top of the (user) address space
-  if((vmn = vmn_allocpg(USTACKPAGES)) == 0)
+  if((vmn = new vmnode(USTACKPAGES)) == 0)
    goto bad;
  if(args->vmap->insert(vmn, USERTOP-(USTACKPAGES*PGSIZE)) < 0)
    goto bad;
@@ -106,7 +106,7 @@ static void dostack(uptr a0, u64 a1)
      goto bad;
    sp -= strlen(args->argv[argc]) + 1;
    sp &= ~7;
-    if(copyout(args->vmap, sp, args->argv[argc], strlen(args->argv[argc]) + 1) < 0)
+    if(args->vmap->copyout(sp, args->argv[argc], strlen(args->argv[argc]) + 1) < 0)
      goto bad;
    ustack[1+argc] = sp;
  }
@@ -118,7 +118,7 @@ static void dostack(uptr a0, u64 a1)
  args->proc->tf->rsi = sp - (argc+1)*8;
  sp -= (1+argc+1) * 8;
-  if(copyout(args->vmap, sp, ustack, (1+argc+1)*8) < 0)
+  if(args->vmap->copyout(sp, ustack, (1+argc+1)*8) < 0)
    goto bad;
  // Save program name for debugging.
@@ -144,7 +144,7 @@ static void doheap(uptr a0, u64 a1)
  prof_start(doheap_prof);
  // Allocate a vmnode for the heap.
  // XXX pre-allocate 32 pages..
-  if((vmn = vmn_allocpg(32)) == 0)
+  if((vmn = new vmnode(32)) == 0)
    goto bad;
  if(args->vmap->insert(vmn, BRK) < 0)
    goto bad;
@@ -161,7 +161,7 @@ int
 exec(char *path, char **argv)
 {
  struct inode *ip = NULL;
-  struct vmap *vmap = NULL;
+  struct vmap *vmp = NULL;
  struct vmnode *vmn = NULL;
  struct elfhdr elf;
  struct proghdr ph;
@@ -183,14 +183,14 @@ exec(char *path, char **argv)
  if(elf.magic != ELF_MAGIC)
    goto bad;
-  if((vmap = vmap_alloc()) == 0)
+  if((vmp = new vmap()) == 0)
    goto bad;
  // Arguments for work queue
  struct eargs args;
  args.proc = myproc();
  args.ip = ip;
-  args.vmap = vmap;
+  args.vmap = vmp;
  args.path = path;
  args.argv = argv;
@@ -225,7 +225,7 @@ exec(char *path, char **argv)
  // Commit to the user image.
  oldvmap = myproc()->vmap;
-  myproc()->vmap = vmap;
+  myproc()->vmap = vmp;
  myproc()->brk = BRK + 8;  // XXX so that brk-1 points within heap vma..
  myproc()->tf->rip = elf.entry;  // main
@@ -238,8 +238,8 @@ exec(char *path, char **argv)
 bad:
  cprintf("exec failed\n");
-  if(vmap)
+  if(vmp)
-    vmap->decref();
+    vmp->decref();
  if(vmn)
    delete vmn;
  gc_end_epoch();

--- a/gc.hh
+++ b/gc.hh
@@ -18,3 +18,13 @@ class rcu_freed {
  virtual void do_gc(void) = 0;
 } __mpalign__;
+void gc_begin_epoch();
+void gc_end_epoch();
+class scoped_gc_epoch {
+ public:
+  scoped_gc_epoch() { gc_begin_epoch(); }
+  ~scoped_gc_epoch() { gc_end_epoch(); }
+};
--- a/kernel.h
+++ b/kernel.h
@@ -97,8 +97,6 @@ void	        dir_flush(struct inode *dp);
 // gc.c
 void            initgc(void);
 void            initprocgc(struct proc *);
-void            gc_begin_epoch();
-void            gc_end_epoch();
 void            gc_start(void);
 #ifdef __cplusplus
@@ -249,12 +247,6 @@ void            uartputc(char c);
 void            uartintr(void);
 // vm.c
-enum vmntype { EAGER, ONDEMAND };
-struct vmap *   vmap_alloc(void);
-struct vmnode*  vmn_alloc(u64, enum vmntype);
-struct vmnode*  vmn_allocpg(u64);
-int             copyout(struct vmap *, uptr, void*, u64);
 void            switchuvm(struct proc*);
 void            switchkvm(void);
 int             pagefault(struct vmap *, uptr, u32);

--- a/ns.hh
+++ b/ns.hh
@@ -14,12 +14,6 @@ using std::atomic;
 #define NHASH 30
 #endif
-class scoped_gc_epoch {
- public:
-  scoped_gc_epoch() { gc_begin_epoch(); }
-  ~scoped_gc_epoch() { gc_end_epoch(); }
-};
 template<class K, class V>
 class xelem : public rcu_freed {
 public:

--- a/proc.cc
+++ b/proc.cc
@@ -274,15 +274,14 @@ inituser(void)
  p = allocproc();
  bootproc = p;
-  if((p->vmap = vmap_alloc()) == 0)
+  if((p->vmap = new vmap()) == 0)
    panic("userinit: out of vmaps?");
-  struct vmnode *vmn = 
+  vmnode *vmn =  new vmnode(PGROUNDUP(_initcode_size) / PGSIZE);
-    vmn_allocpg(PGROUNDUP(_initcode_size) / PGSIZE);
  if(vmn == 0)
    panic("userinit: vmn_allocpg");
  if(p->vmap->insert(vmn, 0) < 0)
    panic("userinit: vmap_insert");
-  if(copyout(p->vmap, 0, _initcode_start, _initcode_size) < 0)
+  if(p->vmap->copyout(0, _initcode_start, _initcode_size) < 0)
    panic("userinit: copyout");
  memset(p->tf, 0, sizeof(*p->tf));
  p->tf->cs = UCSEG | 0x3;
@@ -464,7 +463,7 @@ growproc(int n)
    return -1;
  }
-  struct vmnode *vmn = vmn_allocpg(PGROUNDUP(newn) / PGSIZE);
+  vmnode *vmn = new vmnode(PGROUNDUP(newn) / PGSIZE);
  if(vmn == 0){
    release(&m->lock);
    cprintf("growproc: vmn_allocpg failed\n");
@@ -680,7 +679,7 @@ threadalloc(void (*fn)(void *), void *arg)
  if (p == NULL)
    return 0;
-  p->vmap = vmap_alloc();
+  p->vmap = new vmap();
  if (p->vmap == NULL) {
    freeproc(p);
    return 0;

--- a/sysproc.cc
+++ b/sysproc.cc
@@ -110,7 +110,7 @@ sys_map(void)
  if (argint64(1, &len) < 0)
    return -1;
-  struct vmnode *vmn = vmn_allocpg(PGROUNDUP(len) / PGSIZE);
+  vmnode *vmn = new vmnode(PGROUNDUP(len) / PGSIZE);
  if (vmn == 0)
    return -1;

--- a/vm.cc
+++ b/vm.cc
--- a/vm.hh
+++ b/vm.hh
@@ -4,9 +4,32 @@
 using std::atomic;
+// A memory object (physical pages or inode).
+enum vmntype { EAGER, ONDEMAND };
+struct vmnode {
+  u64 npages;
+  char *page[128];
+  atomic<u64> ref;
+  enum vmntype type;
+  struct inode *ip;
+  u64 offset;
+  u64 sz;
+  vmnode(u64 npg, vmntype type = EAGER);
+  ~vmnode();
+  void decref();
+  int allocpg();
+  vmnode* copy();
+  int load(inode *ip, u64 offset, u64 sz);
+  int demand_load();
+};
 // A mapping of a chunk of an address space to
 // a specific memory object.
-enum vmatype { PRIVATE, COW};
+enum vmatype { PRIVATE, COW };
 struct vma : public rcu_freed {
  uptr va_start;               // start of mapping
  uptr va_end;                 // one past the last byte
@@ -25,25 +48,6 @@ struct vma : public rcu_freed {
  virtual void do_gc() { delete this; }
 };
-// A memory object (physical pages or inode).
-struct vmnode {
-  u64 npages;
-  char *page[128];
-  atomic<u64> ref;
-  enum vmntype type;
-  struct inode *ip;
-  u64 offset;
-  u64 sz;
-  vmnode(u64 npg, vmntype type);
-  ~vmnode();
-  void decref();
-  int allocpg();
-  int load(inode *ip, u64 offset, u64 sz);
-  int demand_load();
-};
 // An address space: a set of vmas plus h/w page table.
 // The elements of e[] are not ordered by address.
 struct vmap {
@@ -63,4 +67,11 @@ struct vmap {
  vma* lookup(uptr start, uptr len);
  int insert(vmnode *n, uptr va_start);
  int remove(uptr start, uptr len);
+  int pagefault(uptr va, u32 err);
+  int copyout(uptr va, void *p, u64 len);
+ private:
+  vma* pagefault_ondemand(uptr va, u32 err, vma *m);
+  int pagefault_wcow(uptr va, pme_t *pte, vma *m, u64 npg);
 };