[src/trunk]: src/sys/ufs/ffs Some changes to "fs->fs_fmod" and "fs->fs_clean":

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

details:   https://anonhg.NetBSD.org/src/rev/fad10a4da10a
branches:  trunk
changeset: 372299:fad10a4da10a
user:      hannken <hannken%NetBSD.org@localhost>
date:      Thu Nov 10 10:53:29 2022 +0000

description:
Some changes to "fs->fs_fmod" and "fs->fs_clean":
- clear "fs->fs_fmod" after reading the super block.
- assert we don't write a super block when mounted read-only.
- make sure "fs->fs_clean" is one of FS_ISCLEAN or FS_WASCLEAN.
- print "file system not clean" on every mount.

Should fix PR kern/57010: ffs: mounting unclean non-root fs read-only
causes spurious write to superblock

diffstat:

 sys/ufs/ffs/ffs_vfsops.c |  33 +++++++++++++++++++--------------
 1 files changed, 19 insertions(+), 14 deletions(-)

diffs (79 lines):

diff -r a321861b61c5 -r fad10a4da10a sys/ufs/ffs/ffs_vfsops.c
--- a/sys/ufs/ffs/ffs_vfsops.c  Thu Nov 10 07:54:20 2022 +0000
+++ b/sys/ufs/ffs/ffs_vfsops.c  Thu Nov 10 10:53:29 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ffs_vfsops.c,v 1.376 2022/04/16 08:00:55 hannken Exp $ */
+/*     $NetBSD: ffs_vfsops.c,v 1.377 2022/11/10 10:53:29 hannken Exp $ */
 
 /*-
  * Copyright (c) 2008, 2009 The NetBSD Foundation, Inc.
@@ -61,7 +61,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ffs_vfsops.c,v 1.376 2022/04/16 08:00:55 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ffs_vfsops.c,v 1.377 2022/11/10 10:53:29 hannken Exp $");
 
 #if defined(_KERNEL_OPT)
 #include "opt_ffs.h"
@@ -683,7 +683,8 @@
                        }
 #endif
                        fs->fs_ronly = 0;
-                       fs->fs_clean <<= 1;
+                       fs->fs_clean =
+                           fs->fs_clean == FS_ISCLEAN ? FS_WASCLEAN : 0;
                        fs->fs_fmod = 1;
 #ifdef WAPBL
                        if (fs->fs_flags & FS_DOWAPBL) {
@@ -743,20 +744,22 @@
            DPRINTF("set_statvfs_info returned %d", error);
        }
        fs->fs_flags &= ~FS_DOSOFTDEP;
-       if (fs->fs_fmod != 0) { /* XXX */
+
+       if ((fs->fs_ronly && (fs->fs_clean & FS_ISCLEAN) == 0) ||
+           (!fs->fs_ronly && (fs->fs_clean & FS_WASCLEAN) == 0)) {
+               printf("%s: file system not clean (fs_clean=%#x); "
+                   "please fsck(8)\n", mp->mnt_stat.f_mntfromname,
+                   fs->fs_clean);
+       }
+
+       if (fs->fs_fmod != 0) {
                int err;
 
-               fs->fs_fmod = 0;
+               KASSERT(!fs->fs_ronly);
+
                if (fs->fs_clean & FS_WASCLEAN)
                        fs->fs_time = time_second;
-               else {
-                       printf("%s: file system not clean (fs_clean=%#x); "
-                           "please fsck(8)\n", mp->mnt_stat.f_mntfromname,
-                           fs->fs_clean);
-                       printf("%s: lost blocks %" PRId64 " files %d\n",
-                           mp->mnt_stat.f_mntfromname, fs->fs_pendingblocks,
-                           fs->fs_pendinginodes);
-               }
+               fs->fs_fmod = 0;
                err = UFS_WAPBL_BEGIN(mp);
                if (err == 0) {
                        (void) ffs_cgupdate(ump, MNT_WAIT);
@@ -1346,6 +1349,7 @@
                }
        }
 
+       fs->fs_fmod = 0;
        if (fs->fs_pendingblocks != 0 || fs->fs_pendinginodes != 0) {
                fs->fs_pendingblocks = 0;
                fs->fs_pendinginodes = 0;
@@ -1427,7 +1431,8 @@
        /* Don't bump fs_clean if we're replaying journal */
        if (!((fs->fs_flags & FS_DOWAPBL) && (fs->fs_clean & FS_WASCLEAN))) {
                if (ronly == 0) {
-                       fs->fs_clean <<= 1;
+                       fs->fs_clean =
+                           fs->fs_clean == FS_ISCLEAN ? FS_WASCLEAN : 0;
                        fs->fs_fmod = 1;
                }
        }