should've been done 6 years ago...
Signed-off-by: Al Viro <[email protected]>
---
fs/namespace.c | 48 ++++++++++++++++++------------------------------
1 files changed, 18 insertions(+), 30 deletions(-)
diff --git a/fs/namespace.c b/fs/namespace.c
index d5cd086..632c551 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -2397,20 +2397,25 @@ static struct mnt_namespace *alloc_mnt_ns(struct user_namespace *user_ns)
return new_ns;
}
-/*
- * Allocate a new namespace structure and populate it with contents
- * copied from the namespace of the passed in task structure.
- */
-static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
- struct user_namespace *user_ns, struct fs_struct *fs)
+struct mnt_namespace *copy_mnt_ns(unsigned long flags, struct mnt_namespace *ns,
+ struct user_namespace *user_ns, struct fs_struct *new_fs)
{
struct mnt_namespace *new_ns;
struct vfsmount *rootmnt = NULL, *pwdmnt = NULL;
struct mount *p, *q;
- struct mount *old = mnt_ns->root;
+ struct mount *old;
struct mount *new;
int copy_flags;
+ BUG_ON(!ns);
+
+ if (likely(!(flags & CLONE_NEWNS))) {
+ get_mnt_ns(ns);
+ return ns;
+ }
+
+ old = ns->root;
+
new_ns = alloc_mnt_ns(user_ns);
if (IS_ERR(new_ns))
return new_ns;
@@ -2418,7 +2423,7 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
namespace_lock();
/* First pass: copy the tree topology */
copy_flags = CL_COPY_UNBINDABLE | CL_EXPIRE;
- if (user_ns != mnt_ns->user_ns)
+ if (user_ns != ns->user_ns)
copy_flags |= CL_SHARED_TO_SLAVE | CL_UNPRIVILEGED;
new = copy_tree(old, old->mnt.mnt_root, copy_flags);
if (IS_ERR(new)) {
@@ -2438,13 +2443,13 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
q = new;
while (p) {
q->mnt_ns = new_ns;
- if (fs) {
- if (&p->mnt == fs->root.mnt) {
- fs->root.mnt = mntget(&q->mnt);
+ if (new_fs) {
+ if (&p->mnt == new_fs->root.mnt) {
+ new_fs->root.mnt = mntget(&q->mnt);
rootmnt = &p->mnt;
}
- if (&p->mnt == fs->pwd.mnt) {
- fs->pwd.mnt = mntget(&q->mnt);
+ if (&p->mnt == new_fs->pwd.mnt) {
+ new_fs->pwd.mnt = mntget(&q->mnt);
pwdmnt = &p->mnt;
}
}
@@ -2465,23 +2470,6 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
return new_ns;
}
-struct mnt_namespace *copy_mnt_ns(unsigned long flags, struct mnt_namespace *ns,
- struct user_namespace *user_ns, struct fs_struct *new_fs)
-{
- struct mnt_namespace *new_ns;
-
- BUG_ON(!ns);
- get_mnt_ns(ns);
-
- if (!(flags & CLONE_NEWNS))
- return ns;
-
- new_ns = dup_mnt_ns(ns, user_ns, new_fs);
-
- put_mnt_ns(ns);
- return new_ns;
-}
-
/**
* create_mnt_ns - creates a private namespace and adds a root filesystem
* @mnt: pointer to the new root filesystem mountpoint
--
1.7.2.5