In nmount(), if we see "update" in the mount options,

set MNT_UPDATE in fsflags, and delete the
"update" option from the global mount options.

MNT_UPDATE is a command, and not a property of a mount
that should persist after the command is executed.

We need to do similar things for MNT_FORCE and MNT_RELOAD.

All mount flags are prefixed by MNT_..... it would
be nice if flags which were commands were named differently
from flags which are persistent properties of a mount.
This was not such a big deal in the pre-nmount() days,
but with nmount() it is more important.

Requested by:	yar
MFC after:	2 weeks

1 files changed, 5 insertions, 4 deletions

diff --git a/sys/kern/vfs_mount.c b/sys/kern/vfs_mount.c
index ade918a..744f4e9 100644
--- a/sys/kern/vfs_mount.c
+++ b/sys/kern/vfs_mount.c
@@ -133,7 +133,6 @@ static const char *global_opts[] = {
 	"rw",
 	"nosuid",
 	"noexec",
-	"update",
 	NULL
 };
 
@@ -586,7 +585,7 @@ static int
 vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions)
 {
 	struct vfsoptlist *optlist;
-	struct vfsopt *opt, *noro_opt;
+	struct vfsopt *opt, *noro_opt, *tmp_opt;
 	char *fstype, *fspath, *errmsg;
 	int error, fstypelen, fspathlen, errmsg_len, errmsg_pos;
 	int has_rw, has_noro;
@@ -632,9 +631,11 @@ vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions)
 	 * logic based on MNT_UPDATE.  This is very important
 	 * when we want to update the root filesystem.
 	 */
-	TAILQ_FOREACH(opt, optlist, link) {
-		if (strcmp(opt->name, "update") == 0)
+	TAILQ_FOREACH_SAFE(opt, optlist, link, tmp_opt) {
+		if (strcmp(opt->name, "update") == 0) {
 			fsflags |= MNT_UPDATE;
+			vfs_freeopt(optlist, opt);
+		}
 		else if (strcmp(opt->name, "async") == 0)
 			fsflags |= MNT_ASYNC;
 		else if (strcmp(opt->name, "force") == 0)