NFS: Add timeout to submounts
Make automounted partitions expire using the mark_mounts_for_expiry()
function. The timeout is controlled via a sysctl.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index a155505..e426516 100644
--- a/fs/nfs/namespace.c
+++ b/fs/nfs/namespace.c
@@ -18,6 +18,11 @@
#define NFSDBG_FACILITY NFSDBG_VFS
+LIST_HEAD(nfs_automount_list);
+static void nfs_expire_automounts(void *list);
+static DECLARE_WORK(nfs_automount_task, nfs_expire_automounts, &nfs_automount_list);
+int nfs_mountpoint_expiry_timeout = 500 * HZ;
+
/*
* nfs_follow_mountpoint - handle crossing a mountpoint on the server
* @dentry - dentry of mountpoint
@@ -59,7 +64,7 @@
goto out_err;
mntget(mnt);
- err = do_add_mount(mnt, nd, nd->mnt->mnt_flags, NULL);
+ err = do_add_mount(mnt, nd, nd->mnt->mnt_flags|MNT_SHRINKABLE, &nfs_automount_list);
if (err < 0) {
mntput(mnt);
if (err == -EBUSY)
@@ -70,6 +75,7 @@
dput(nd->dentry);
nd->mnt = mnt;
nd->dentry = dget(mnt->mnt_root);
+ schedule_delayed_work(&nfs_automount_task, nfs_mountpoint_expiry_timeout);
out:
dprintk("%s: done, returned %d\n", __FUNCTION__, err);
return ERR_PTR(err);
@@ -87,3 +93,20 @@
.follow_link = nfs_follow_mountpoint,
.getattr = nfs_getattr,
};
+
+static void nfs_expire_automounts(void *data)
+{
+ struct list_head *list = (struct list_head *)data;
+
+ mark_mounts_for_expiry(list);
+ if (!list_empty(list))
+ schedule_delayed_work(&nfs_automount_task, nfs_mountpoint_expiry_timeout);
+}
+
+void nfs_release_automount_timer(void)
+{
+ if (list_empty(&nfs_automount_list)) {
+ cancel_delayed_work(&nfs_automount_task);
+ flush_scheduled_work();
+ }
+}