1 files changed, 2 insertions, 3 deletions
diff --git a/kernel/buf.h b/kernel/buf.h
index 3266495..4a3a39d 100644
--- a/kernel/buf.h
+++ b/kernel/buf.h
@@ -1,5 +1,6 @@
 struct buf {
-  int flags;
+  int valid;   // has data been read from disk?
+  int disk;    // does disk "own" buf?
   uint dev;
   uint blockno;
   struct sleeplock lock;
@@ -9,6 +10,4 @@ struct buf {
   struct buf *qnext; // disk queue
   uchar data[BSIZE];
 };
-#define B_VALID 0x2  // buffer has been read from disk
-#define B_DIRTY 0x4  // buffer needs to be written to disk