Take the completion of automount into new helper

... and shift it from namei.c to namespace.c

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2011-01-17 01:35:23 -05:00
parent e78bf5e6cb
commit 19a167af7c
3 changed files with 39 additions and 26 deletions

View File

@ -70,6 +70,7 @@ extern void mnt_set_mountpoint(struct vfsmount *, struct dentry *,
extern void release_mounts(struct list_head *);
extern void umount_tree(struct vfsmount *, int, struct list_head *);
extern struct vfsmount *copy_tree(struct vfsmount *, struct dentry *, int);
extern int finish_automount(struct vfsmount *, struct path *);
extern int do_add_mount(struct vfsmount *, struct path *, int);
extern void mnt_clear_expiry(struct vfsmount *);

View File

@ -923,37 +923,13 @@ static int follow_automount(struct path *path, unsigned flags,
if (!mnt) /* mount collision */
return 0;
/* The new mount record should have at least 2 refs to prevent it being
* expired before we get a chance to add it
*/
BUG_ON(mnt_get_count(mnt) < 2);
err = finish_automount(mnt, path);
if (mnt->mnt_sb == path->mnt->mnt_sb &&
mnt->mnt_root == path->dentry) {
mnt_clear_expiry(mnt);
mntput(mnt);
mntput(mnt);
return -ELOOP;
}
/* We need to add the mountpoint to the parent. The filesystem may
* have placed it on an expiry list, and so we need to make sure it
* won't be expired under us if do_add_mount() fails (do_add_mount()
* will eat a reference unconditionally).
*/
mntget(mnt);
err = do_add_mount(mnt, path, path->mnt->mnt_flags | MNT_SHRINKABLE);
switch (err) {
case -EBUSY:
/* Someone else made a mount here whilst we were busy */
err = 0;
default:
mnt_clear_expiry(mnt);
mntput(mnt);
mntput(mnt);
return err;
return 0;
case 0:
mntput(mnt);
dput(path->dentry);
if (*need_mntput)
mntput(path->mnt);
@ -961,7 +937,10 @@ static int follow_automount(struct path *path, unsigned flags,
path->dentry = dget(mnt->mnt_root);
*need_mntput = true;
return 0;
default:
return err;
}
}
/*

View File

@ -1895,6 +1895,39 @@ static int do_new_mount(struct path *path, char *type, int flags,
return do_add_mount(mnt, path, mnt_flags);
}
int finish_automount(struct vfsmount *m, struct path *path)
{
int err;
/* The new mount record should have at least 2 refs to prevent it being
* expired before we get a chance to add it
*/
BUG_ON(mnt_get_count(m) < 2);
if (m->mnt_sb == path->mnt->mnt_sb &&
m->mnt_root == path->dentry) {
mnt_clear_expiry(m);
mntput(m);
mntput(m);
return -ELOOP;
}
/* We need to add the mountpoint to the parent. The filesystem may
* have placed it on an expiry list, and so we need to make sure it
* won't be expired under us if do_add_mount() fails (do_add_mount()
* will eat a reference unconditionally).
*/
mntget(m);
err = do_add_mount(m, path, path->mnt->mnt_flags | MNT_SHRINKABLE);
if (err) {
mnt_clear_expiry(m);
mntput(m);
mntput(m);
} else {
mntput(m);
}
return err;
}
/*
* add a mount into a namespace's mount tree
* - this unconditionally eats one of the caller's references to newmnt.