When downgrading the read-write mount to read-only, do_unmount() sets

MNT_RDONLY flag before the VFS_MOUNT() is called. In ufs_inactive()
and ufs_itimes_locked(), UFS verifies whether the fs is read-only by
checking MNT_RDONLY, but this may cause loss of the IN_MODIFIED flag
for inode on the fs being remounted rw->ro.

Introduce UFS_RDONLY() struct ufsmount' method that reports the value
of the fs_ronly. The later is set to 1 only after the remount is
finished.

Reviewed by:	tegge
In collaboration with:	pho
MFC after:	 1 month

6 files changed, 16 insertions, 4 deletions

diff --git a/sys/ufs/ffs/ffs_extern.h b/sys/ufs/ffs/ffs_extern.h
index 22afbaa..d5dfa12 100644
--- a/sys/ufs/ffs/ffs_extern.h
+++ b/sys/ufs/ffs/ffs_extern.h
@@ -131,4 +131,6 @@ int     softdep_process_worklist(struct mount *, int);
 int     softdep_fsync(struct vnode *);
 int	softdep_waitidle(struct mount *);
 
+int	ffs_rdonly(struct inode *);
+
 #endif /* !_UFS_FFS_EXTERN_H */
diff --git a/sys/ufs/ffs/ffs_inode.c b/sys/ufs/ffs/ffs_inode.c
index 0a9bc9d..4c58e41 100644
--- a/sys/ufs/ffs/ffs_inode.c
+++ b/sys/ufs/ffs/ffs_inode.c
@@ -646,3 +646,11 @@ ffs_indirtrunc(ip, lbn, dbn, lastbn, level, countp)
 	*countp = blocksreleased;
 	return (allerror);
 }
+
+int
+ffs_rdonly(struct inode *ip)
+{
+
+	return (ip->i_ump->um_fs->fs_ronly != 0);
+}
+
diff --git a/sys/ufs/ffs/ffs_vfsops.c b/sys/ufs/ffs/ffs_vfsops.c
index 91cd7cf..67d4496 100644
--- a/sys/ufs/ffs/ffs_vfsops.c
+++ b/sys/ufs/ffs/ffs_vfsops.c
@@ -734,6 +734,7 @@ ffs_mountfs(devvp, mp, td)
 	ump->um_valloc = ffs_valloc;
 	ump->um_vfree = ffs_vfree;
 	ump->um_ifree = ffs_ifree;
+	ump->um_rdonly = ffs_rdonly;
 	mtx_init(UFS_MTX(ump), "FFS", "FFS Lock", MTX_DEF);
 	bcopy(bp->b_data, ump->um_fs, (u_int)fs->fs_sbsize);
 	if (fs->fs_sbsize < SBLOCKSIZE)
diff --git a/sys/ufs/ufs/ufs_inode.c b/sys/ufs/ufs/ufs_inode.c
index 57ede1e..17ec28e 100644
--- a/sys/ufs/ufs/ufs_inode.c
+++ b/sys/ufs/ufs/ufs_inode.c
@@ -90,8 +90,7 @@ ufs_inactive(ap)
 	ufs_gjournal_close(vp);
 #endif
 	if ((ip->i_effnlink == 0 && DOINGSOFTDEP(vp)) ||
-	    (ip->i_nlink <= 0 &&
-	     (vp->v_mount->mnt_flag & MNT_RDONLY) == 0)) {
+	    (ip->i_nlink <= 0 && !UFS_RDONLY(ip))) {
 	loop:
 		if (vn_start_secondary_write(vp, &mp, V_NOWAIT) != 0) {
 			/* Cannot delete file while file system is suspended */
@@ -121,7 +120,7 @@ ufs_inactive(ap)
 	}
 	if (ip->i_effnlink == 0 && DOINGSOFTDEP(vp))
 		softdep_releasefile(ip);
-	if (ip->i_nlink <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
+	if (ip->i_nlink <= 0 && !UFS_RDONLY(ip)) {
 #ifdef QUOTA
 		if (!getinoquota(ip))
 			(void)chkiq(ip, -1, NOCRED, FORCE);
diff --git a/sys/ufs/ufs/ufs_vnops.c b/sys/ufs/ufs/ufs_vnops.c
index d3a5c70..506ab6a 100644
--- a/sys/ufs/ufs/ufs_vnops.c
+++ b/sys/ufs/ufs/ufs_vnops.c
@@ -135,7 +135,7 @@ ufs_itimes_locked(struct vnode *vp)
 	ASSERT_VI_LOCKED(vp, __func__);
 
 	ip = VTOI(vp);
-	if ((vp->v_mount->mnt_flag & MNT_RDONLY) != 0)
+	if (UFS_RDONLY(ip))
 		goto out;
 	if ((ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_UPDATE)) == 0)
 		return;
diff --git a/sys/ufs/ufs/ufsmount.h b/sys/ufs/ufs/ufsmount.h
index 50a0941..126867b 100644
--- a/sys/ufs/ufs/ufsmount.h
+++ b/sys/ufs/ufs/ufsmount.h
@@ -93,6 +93,7 @@ struct ufsmount {
 	int	(*um_valloc)(struct vnode *, int, struct ucred *, struct vnode **);
 	int	(*um_vfree)(struct vnode *, ino_t, int);
 	void	(*um_ifree)(struct ufsmount *, struct inode *);
+	int	(*um_rdonly)(struct inode *);
 };
 
 #define UFS_BALLOC(aa, bb, cc, dd, ee, ff) VFSTOUFS((aa)->v_mount)->um_balloc(aa, bb, cc, dd, ee, ff)
@@ -102,6 +103,7 @@ struct ufsmount {
 #define UFS_VALLOC(aa, bb, cc, dd) VFSTOUFS((aa)->v_mount)->um_valloc(aa, bb, cc, dd)
 #define UFS_VFREE(aa, bb, cc) VFSTOUFS((aa)->v_mount)->um_vfree(aa, bb, cc)
 #define UFS_IFREE(aa, bb) ((aa)->um_ifree(aa, bb))
+#define	UFS_RDONLY(aa) ((aa)->i_ump->um_rdonly(aa))
 
 #define	UFS_LOCK(aa)	mtx_lock(&(aa)->um_lock)
 #define	UFS_UNLOCK(aa)	mtx_unlock(&(aa)->um_lock)