[PATCH 1/2] HFSPlus: clear dirty flags on remount read-only

["Timo Schlüßler" <timo@schluessler.org>]

Remounting a HFSPlus filesystem read-only doesn't clear the "DIRTY"-flags
(not HFSPLUS_VOL_UNMNT and HFSPLUS_VOL_INCNSTNT) correctly. Subsequent
mounts then report a dirty filesystem and enforce a check before willing
to mount it read-write again.
Signed-off-by: Timo Schlüßler <timo@schluessler.org>
---

--- linux/fs/hfsplus/super.c.orig       2015-11-22 20:11:25.000000000 +0100
+++ linux/fs/hfsplus/super.c    2015-11-22 20:14:38.000000000 +0100
@@ -325,11 +325,12 @@ static int hfsplus_statfs(struct dentry

 static int hfsplus_remount(struct super_block *sb, int *flags, char *data)
 {
+       struct hfsplus_vh *vhdr = HFSPLUS_SB(sb)->s_vhdr;
+
        sync_filesystem(sb);
        if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
                return 0;
        if (!(*flags & MS_RDONLY)) {
-               struct hfsplus_vh *vhdr = HFSPLUS_SB(sb)->s_vhdr;
                int force = 0;

                if (!hfsplus_parse_options_remount(data, &force))
@@ -352,6 +353,12 @@ static int hfsplus_remount(struct super_
                        sb->s_flags |= MS_RDONLY;
                        *flags |= MS_RDONLY;
                }
+       } else {
+               vhdr->modify_date = hfsp_now2mt();
+               vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_UNMNT);
+               vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_INCNSTNT);
+
+               hfsplus_sync_fs(sb, 1);
        }
        return 0;
 }