fix getblk to actually lock the block

no more cons_put system calls
usertests tests two processes writing files

1 files changed, 2 insertions, 0 deletions

diff --git a/buf.h b/buf.h
index a4cea5e..e3f6b14 100644
--- a/buf.h
+++ b/buf.h
@@ -1,5 +1,7 @@
 struct buf {
   int flags;
+  uint dev;
+  uint sector;
   uchar data[512];
 };
 #define B_BUSY 0x1