Staging: octeon-ethernet: Convert to use net_device_ops.

[pandora-kernel.git] / fs / namespace.c

diff --git a/fs/namespace.c b/fs/namespace.c
index 2dd333b..a7bea8c 100644 (file)
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1937,6 +1937,21 @@ dput_out:
        return retval;
 }
 
+static struct mnt_namespace *alloc_mnt_ns(void)
+{
+       struct mnt_namespace *new_ns;
+
+       new_ns = kmalloc(sizeof(struct mnt_namespace), GFP_KERNEL);
+       if (!new_ns)
+               return ERR_PTR(-ENOMEM);
+       atomic_set(&new_ns->count, 1);
+       new_ns->root = NULL;
+       INIT_LIST_HEAD(&new_ns->list);
+       init_waitqueue_head(&new_ns->poll);
+       new_ns->event = 0;
+       return new_ns;
+}
+
 /*
  * Allocate a new namespace structure and populate it with contents
  * copied from the namespace of the passed in task structure.
@@ -1948,14 +1963,9 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
        struct vfsmount *rootmnt = NULL, *pwdmnt = NULL;
        struct vfsmount *p, *q;
 
-       new_ns = kmalloc(sizeof(struct mnt_namespace), GFP_KERNEL);
-       if (!new_ns)
-               return ERR_PTR(-ENOMEM);
-
-       atomic_set(&new_ns->count, 1);
-       INIT_LIST_HEAD(&new_ns->list);
-       init_waitqueue_head(&new_ns->poll);
-       new_ns->event = 0;
+       new_ns = alloc_mnt_ns();
+       if (IS_ERR(new_ns))
+               return new_ns;
 
        down_write(&namespace_sem);
        /* First pass: copy the tree topology */
@@ -2019,6 +2029,24 @@ struct mnt_namespace *copy_mnt_ns(unsigned long flags, struct mnt_namespace *ns,
        return new_ns;
 }
 
+/**
+ * create_mnt_ns - creates a private namespace and adds a root filesystem
+ * @mnt: pointer to the new root filesystem mountpoint
+ */
+struct mnt_namespace *create_mnt_ns(struct vfsmount *mnt)
+{
+       struct mnt_namespace *new_ns;
+
+       new_ns = alloc_mnt_ns();
+       if (!IS_ERR(new_ns)) {
+               mnt->mnt_ns = new_ns;
+               new_ns->root = mnt;
+               list_add(&new_ns->list, &new_ns->root->mnt_list);
+       }
+       return new_ns;
+}
+EXPORT_SYMBOL(create_mnt_ns);
+
 SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name,
                char __user *, type, unsigned long, flags, void __user *, data)
 {
@@ -2246,10 +2274,14 @@ void __init mnt_init(void)
        init_mount_tree();
 }
 
-void __put_mnt_ns(struct mnt_namespace *ns)
+void put_mnt_ns(struct mnt_namespace *ns)
 {
-       struct vfsmount *root = ns->root;
+       struct vfsmount *root;
        LIST_HEAD(umount_list);
+
+       if (!atomic_dec_and_lock(&ns->count, &vfsmount_lock))
+               return;
+       root = ns->root;
        ns->root = NULL;
        spin_unlock(&vfsmount_lock);
        down_write(&namespace_sem);
@@ -2260,3 +2292,4 @@ void __put_mnt_ns(struct mnt_namespace *ns)
        release_mounts(&umount_list);
        kfree(ns);
 }
+EXPORT_SYMBOL(put_mnt_ns);