Take the completion of automount into new helper (19a167af) · Commits · 戴 / test

fs/internal.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -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 *);

+5 −26

Original line number	Diff line number	Diff line
		@@ -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;
		}

		}

		/*

+33 −0

Original line number	Diff line number	Diff line
		@@ -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.