Introduce and use sleeplocks instead of BUSY flags

Remove I_BUSY, B_BUSY, and intrans defs and usages
One spinlock per buf to avoid ugly loop in bget
fix race in filewrite (don't update f->off after releasing lock)

1 files changed, 3 insertions, 3 deletions

diff --git a/file.h b/file.h
index 55918cc..d7d8fed 100644
--- a/file.h
+++ b/file.h
@@ -15,7 +15,9 @@ struct inode {
   uint dev;           // Device number
   uint inum;          // Inode number
   int ref;            // Reference count
-  int flags;          // I_BUSY, I_VALID
+  int flags;          // I_VALID
+  struct spinlock lock;
+  struct sleeplock sleeplock;
 
   short type;         // copy of disk inode
   short major;
@@ -25,10 +27,8 @@ struct inode {
   uint addrs[NDIRECT+1];
 };
 
-#define I_BUSY 0x1
 #define I_VALID 0x2
 
-
 // device implementations
 
 struct devsw {