[src/trunk]: src/sys/arch/cobalt/cobalt Add bounds_check_with_label().

[soren <soren%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/017c12d26ebb
branches:  trunk
changeset: 483926:017c12d26ebb
user:      soren <soren%NetBSD.org@localhost>
date:      Tue Mar 21 02:26:48 2000 +0000

description:
Add bounds_check_with_label().

diffstat:

 sys/arch/cobalt/cobalt/disksubr.c |  65 +++++++++++++++++++++++++++++++++------
 1 files changed, 55 insertions(+), 10 deletions(-)

diffs (83 lines):

diff -r b9e574c6207e -r 017c12d26ebb sys/arch/cobalt/cobalt/disksubr.c
--- a/sys/arch/cobalt/cobalt/disksubr.c Tue Mar 21 02:24:30 2000 +0000
+++ b/sys/arch/cobalt/cobalt/disksubr.c Tue Mar 21 02:26:48 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: disksubr.c,v 1.1 2000/03/19 23:07:44 soren Exp $       */
+/*     $NetBSD: disksubr.c,v 1.2 2000/03/21 02:26:48 soren Exp $       */
 
 /*
  * Copyright (c) 1982, 1986, 1988 Regents of the University of California.
@@ -76,15 +76,6 @@
        return ENODEV;
 }
 
-int      
-bounds_check_with_label(bp, lp, wlabel) 
-       struct buf *bp;
-       struct disklabel *lp;
-       int wlabel; 
-{               
-       return 1;
-}
-
 void
 dk_establish(dk, dev)
        struct disk *dk;
@@ -339,3 +330,57 @@
         brelse(bp);
        return (rv);
 }
+
+/*
+ * Determine the size of the transfer, and make sure it is
+ * within the boundaries of the partition. Adjust transfer
+ * if needed, and signal errors or early completion.
+ */
+int
+bounds_check_with_label(bp, lp, wlabel)
+       struct buf *bp;
+       struct disklabel *lp;
+       int wlabel;
+{
+       struct partition *p = lp->d_partitions + DISKPART(bp->b_dev);
+       int labelsector = lp->d_partitions[2].p_offset + LABELSECTOR;
+       int sz;
+
+       sz = howmany(bp->b_bcount, lp->d_secsize);
+
+       if (bp->b_blkno + sz > p->p_size) {
+               sz = p->p_size - bp->b_blkno;
+               if (sz == 0) {
+                       /* If exactly at end of disk, return EOF. */
+                       bp->b_resid = bp->b_bcount;
+                       goto done;
+               }
+               if (sz < 0) {
+                       /* If past end of disk, return EINVAL. */
+                       bp->b_error = EINVAL;
+                       goto bad;
+               }
+               /* Otherwise, truncate request. */
+               bp->b_bcount = sz << DEV_BSHIFT;
+       }
+
+       /* Overwriting disk label? */
+       if (bp->b_blkno + p->p_offset <= labelsector &&
+#if LABELSECTOR != 0
+           bp->b_blkno + p->p_offset + sz > labelsector &&
+#endif
+           (bp->b_flags & B_READ) == 0 && !wlabel) {
+               bp->b_error = EROFS;
+               goto bad;
+       }
+
+       /* Calculate cylinder for disksort to order transfers with. */
+       bp->b_cylinder = (bp->b_blkno + p->p_offset) /
+           (lp->d_secsize / DEV_BSIZE) / lp->d_secpercyl;
+       return (1);
+
+bad:
+       bp->b_flags |= B_ERROR;
+done:
+       return (0);
+}