diff options
| -rw-r--r-- | fs/internal.h | 1 | ||||
| -rw-r--r-- | fs/namei.c | 31 | ||||
| -rw-r--r-- | fs/namespace.c | 33 |
3 files changed, 39 insertions, 26 deletions
diff --git a/fs/internal.h b/fs/internal.h index 12ccb86edef7..e8a0b245177d 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -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 *); diff --git a/fs/namei.c b/fs/namei.c index 8f7b41a14882..b753192d8c3f 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -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); - - if (mnt->mnt_sb == path->mnt->mnt_sb && - mnt->mnt_root == path->dentry) { - mnt_clear_expiry(mnt); - mntput(mnt); - mntput(mnt); - return -ELOOP; - } + err = finish_automount(mnt, path); - /* 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; } + } /* diff --git a/fs/namespace.c b/fs/namespace.c index 9f544f35ed34..bec51e4e0549 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -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. |