iincref returns new ref

defs.h

@@ -128,7 +128,7 @@ void ilock(struct inode*);
 void iunlock(struct inode*);
 void itrunc(struct inode*);
 void idecref(struct inode*);
-void iincref(struct inode*);
+struct inode* iincref(struct inode*);
 void iput(struct inode*);
 struct inode* namei(char*, int, uint*, char**, struct inode**);
 void stati(struct inode*, struct stat*);

fs.c

@@ -266,8 +266,7 @@ iunlock(struct inode *ip)
 uint
 bmap(struct inode *ip, uint bn)
 {
-  unsigned x;
+  uint *a, x;
-  uint *a;
   struct buf *inbp;
 
   if(bn >= MAXFILE)
@@ -350,12 +349,14 @@ idecref(struct inode *ip)
 }
 
 // Increment reference count for ip.
-void
+// Returns ip to enable ip = iincref(ip1) idiom.
+struct inode*
 iincref(struct inode *ip)
 {
   ilock(ip);
   ip->ref++;
   iunlock(ip);
+  return ip;
 }
 
 // Copy stat information from inode.
@@ -511,8 +512,7 @@ namei(char *path, int mode, uint *ret_off,
   if(*cp == '/')
     dp = iget(rootdev, 1);
   else {
-    dp = p->cwd;
+    dp = iincref(p->cwd);
-    iincref(dp);
     ilock(dp);
   }
 

proc.c

@@ -150,8 +150,7 @@ copyproc(struct proc *p)
       fileincref(np->ofile[i]);
   }
 
-  np->cwd = p->cwd;
+  np->cwd = iincref(p->cwd);
-  iincref(p->cwd);
 
   return np;
 }