[src/trunk]: src/sys/dev/raidframe Fix a long long-standing off-by-one error ...

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

details:   https://anonhg.NetBSD.org/src/rev/44f6a7290f0c
branches:  trunk
changeset: 959496:44f6a7290f0c
user:      oster <oster%NetBSD.org@localhost>
date:      Mon Feb 15 23:27:03 2021 +0000

description:
Fix a long long-standing off-by-one error in computing lastPSID.

SUsPerPU is only really supported for a value of 1, and since the
first PSID is 0, the last will be numStripe-1.  Also update the
setting of pending_writes to reflect the change to lastPSID.

Needs pullups to -8 and -9.

diffstat:

 sys/dev/raidframe/rf_reconstruct.c |  9 ++++-----
 1 files changed, 4 insertions(+), 5 deletions(-)

diffs (44 lines):

diff -r a8acd27b290c -r 44f6a7290f0c sys/dev/raidframe/rf_reconstruct.c
--- a/sys/dev/raidframe/rf_reconstruct.c        Mon Feb 15 23:00:03 2021 +0000
+++ b/sys/dev/raidframe/rf_reconstruct.c        Mon Feb 15 23:27:03 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: rf_reconstruct.c,v 1.124 2019/12/08 12:14:40 mlelstv Exp $     */
+/*     $NetBSD: rf_reconstruct.c,v 1.125 2021/02/15 23:27:03 oster Exp $       */
 /*
  * Copyright (c) 1995 Carnegie-Mellon University.
  * All rights reserved.
@@ -33,7 +33,7 @@
  ************************************************************/
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: rf_reconstruct.c,v 1.124 2019/12/08 12:14:40 mlelstv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: rf_reconstruct.c,v 1.125 2021/02/15 23:27:03 oster Exp $");
 
 #include <sys/param.h>
 #include <sys/time.h>
@@ -616,7 +616,7 @@
        mapPtr = raidPtr->reconControl->reconMap;
 
        incPSID = RF_RECONMAP_SIZE;
-       lastPSID = raidPtr->Layout.numStripe / raidPtr->Layout.SUsPerPU;
+       lastPSID = raidPtr->Layout.numStripe / raidPtr->Layout.SUsPerPU - 1;
        RUsPerPU = raidPtr->Layout.SUsPerPU / raidPtr->Layout.SUsPerRU;
        recon_error = 0;
        write_error = 0;
@@ -631,7 +631,7 @@
                raidPtr->reconControl->lastPSID = lastPSID;
 
        if (pending_writes > lastPSID)
-               pending_writes = lastPSID;
+               pending_writes = lastPSID + 1;
 
        /* start the actual reconstruction */
 
@@ -796,7 +796,6 @@
                        pending_writes = lastPSID - prev;
                        raidPtr->reconControl->lastPSID = lastPSID;
                }
-               
                /* back down curPSID to get ready for the next round... */
                for (i = 0; i < raidPtr->numCol; i++) {
                        if (i != col) {