nit

cat.c

@@ -5,7 +5,7 @@
 char buf[512];
 
 void
-rfile(int fd)
+cat(int fd)
 {
   int n;
 
@@ -23,7 +23,7 @@ main(int argc, char *argv[])
   int fd, i;
 
   if(argc <= 1) {
-    rfile(0);
+    cat(0);
     exit();
   }
 
@@ -32,7 +32,7 @@ main(int argc, char *argv[])
       printf(1, "cat: cannot open %s\n", argv[i]);
       exit();
     }
-    rfile(fd);
+    cat(fd);
     close(fd);
   }
   exit();

fcntl.h

-#define O_CREATE  0x200
 #define O_RDONLY  0x000
 #define O_WRONLY  0x001
 #define O_RDWR    0x002
+#define O_CREATE  0x200

fs.c

@@ -205,7 +205,7 @@ ilock(struct inode *ip)
 
   if(!(ip->flags & I_VALID)){
     bp = bread(ip->dev, IBLOCK(ip->inum));
-    dip = &((struct dinode*)(bp->data))[ip->inum % IPB];
+    dip = (struct dinode*)bp->data + ip->inum%IPB;
     ip->type = dip->type;
     ip->major = dip->major;
     ip->minor = dip->minor;
@@ -275,7 +275,7 @@ ialloc(uint dev, short type)
   readsb(dev, &sb);
   for(inum = 1; inum < sb.ninodes; inum++) {  // loop over inode blocks
     bp = bread(dev, IBLOCK(inum));
-    dip = (struct dinode*)(bp->data) + inum%IPB;
+    dip = (struct dinode*)bp->data + inum%IPB;
     if(dip->type == 0) {  // a free inode
       memset(dip, 0, sizeof(*dip));
       dip->type = type;
@@ -296,7 +296,7 @@ iupdate(struct inode *ip)
   struct dinode *dip;
 
   bp = bread(ip->dev, IBLOCK(ip->inum));
-  dip = (struct dinode*)(bp->data) + ip->inum%IPB;
+  dip = (struct dinode*)bp->data + ip->inum%IPB;
   dip->type = ip->type;
   dip->major = ip->major;
   dip->minor = ip->minor;

main.c

@@ -5,9 +5,7 @@
 #include "proc.h"
 #include "x86.h"
 
-extern char edata[], end[];
-
-void bootothers(void);
+static void bootothers(void);
 
 // Bootstrap processor starts running C code here.
 int
@@ -15,6 +13,7 @@ main(void)
 {
   int i;
   static volatile int bcpu;  // cannot be on stack
+  extern char edata[], end[];
 
   // clear BSS
   memset(edata, 0, end - edata);
@@ -65,7 +64,6 @@ mpmain(void)
   idtinit();
   lapic_init(cpu());
   setupsegs(0);
-
   cpuid(0, 0, 0, 0, 0);  // memory barrier
   cpus[cpu()].booted = 1;
 
@@ -76,7 +74,7 @@ mpmain(void)
   scheduler();
 }
 
-void
+static void
 bootothers(void)
 {
   extern uchar _binary_bootother_start[], _binary_bootother_size[];
@@ -91,7 +89,7 @@ bootothers(void)
     if(c == cpus+cpu())  // We've started already.
       continue;
 
-    // Set target %esp, %eip
+    // Fill in %esp, %eip and start code on cpu.
     *(void**)(code-4) = c->mpstack + MPSTACK;
     *(void**)(code-8) = mpmain;
     lapic_startap(c->apicid, (uint)code);