Various cleanup:

 - Got rid of dummy proc[0].  Now proc[0] is init.
 - Added initcode.S to exec /init, so that /init is
   just a regular binary.
 - Moved exec out of sysfile to exec.c
 - Moved code dealing with fs guts (like struct inode)
   from sysfile.c to fs.c.  Code dealing with system call
   arguments stays in sysfile.c
 - Refactored directory routines in fs.c; should be simpler.
 - Changed iget to return *unlocked* inode structure.
   This solves the lookup-then-use race in namei
   without introducing deadlocks.
   It also enabled getting rid of the dummy proc[0].

1 files changed, 3 insertions, 4 deletions

diff --git a/fsvar.h b/fsvar.h
index 449bf3d..8609c2a 100644
--- a/fsvar.h
+++ b/fsvar.h
@@ -4,7 +4,7 @@ struct inode {
   uint dev;           // Device number
   uint inum;          // Inode number
   int ref;            // Reference count
-  int busy;           // Is the inode "locked"?
+  int flags;           // I_BUSY, I_VALID
 
   short type;         // copy of disk inode
   short major;
@@ -16,6 +16,5 @@ struct inode {
 
 #define ROOTDEV  1   // Device number of root file system
 
-#define NAMEI_LOOKUP 1
-#define NAMEI_CREATE 2
-#define NAMEI_DELETE 3
+#define I_BUSY 0x1
+#define I_VALID 0x2