bread_cluster() can be called unconditionally. The sequential check is
a leftover of the read-ahead mechanism that FFS no longer used since the
introduction of the Dynamic Buffer cache.
ok?
Index: ufs/ffs/ffs_vnops.c
===================================================================
RCS file: /cvs/src/sys/ufs/ffs/ffs_vnops.c,v
retrieving revision 1.80
diff -u -p -r1.80 ffs_vnops.c
--- ufs/ffs/ffs_vnops.c 14 Mar 2015 03:38:52 -0000 1.80
+++ ufs/ffs/ffs_vnops.c 3 Jan 2016 21:42:22 -0000
@@ -242,14 +242,11 @@ ffs_read(void *v)
if (lblktosize(fs, nextlbn) >= DIP(ip, size))
error = bread(vp, lbn, size, &bp);
- else if (lbn - 1 == ip->i_ci.ci_lastr) {
+ else
error = bread_cluster(vp, lbn, size, &bp);
- } else
- error = bread(vp, lbn, size, &bp);
if (error)
break;
- ip->i_ci.ci_lastr = lbn;
/*
* We should only get non-zero b_resid when an I/O error
