hjfs: Add comment to change the OFF size to 8 when given the chance

sys/src/cmd/hjfs/dat.h

@@ -79,6 +79,11 @@ struct Dentry {
 enum {
 	DENTRYSIZ = NAMELEN + 4 * sizeof(ushort) + 13 + (3 + NDIRECT + NINDIRECT) * sizeof(uvlong),
 	DEPERBLK = RBLOCK / DENTRYSIZ,
+	/* Given any opportunity to make a breaking change to hjfs,
+	 * make this 12 an 8. Indirect offsets to blocks used to
+	 * hold an incrementing  4 byte generation number. That
+	 * design has changed.
+	 */
 	OFFPERBLK = RBLOCK / 12,
 	REFSIZ = 3,
 	REFPERBLK = RBLOCK / REFSIZ,
@@ -185,8 +190,8 @@ enum {
 	CHREAD = 1,
 	CHWRITE = 2,
 	CHRCLOSE = 4,
-	CHFDUMP = 1,
 
+	CHFDUMP = 1,
 	CHFNOLOCK = 2,
 	CHFRO = 4,
 	CHFNOPERM = 8,

sys/src/cmd/hjfs/fs1.c

@@ -449,7 +449,7 @@ freeit:
 		if((l->flags & LGONE) != 0){
 			/*
 			 * safe to unlock here, the file is gone and
-			 * we'r the last reference.
+			 * we're the last reference.
 			 */
 			qunlock(&fs->loctree);
 			b = getbuf(fs->d, l->blk, TDENTRY, 0);

sys/src/cmd/hjfs/fs2.c

@@ -100,7 +100,6 @@ namevalid(char *name)
 	return p - name < NAMELEN;
 }
 
-
 int
 chancreat(Chan *ch, char *name, int perm, int mode)
 {