Commit 520d7c86 authored by Miklos Szeredi's avatar Miklos Szeredi
Browse files

ovl: move ovl_get_workdir() and ovl_get_lower_layers() 



Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent 6e88256e

fs/overlayfs/super.c

+101 −101
Original line number Diff line number Diff line
@@ -864,58 +864,6 @@ out: 
	return err;

}



static int ovl_get_workpath(struct ovl_fs *ufs, struct path *upperpath,

			    struct path *workpath)

{

	int err;



	err = ovl_mount_dir(ufs->config.workdir, workpath);

	if (err)

		goto out;



	err = -EINVAL;

	if (upperpath->mnt != workpath->mnt) {

		pr_err("overlayfs: workdir and upperdir must reside under the same mount\n");

		goto out;

	}

	if (!ovl_workdir_ok(workpath->dentry, upperpath->dentry)) {

		pr_err("overlayfs: workdir and upperdir must be separate subtrees\n");

		goto out;

	}



	err = -EBUSY;

	if (ovl_inuse_trylock(workpath->dentry)) {

		ufs->workdir_locked = true;

	} else if (ufs->config.index) {

		pr_err("overlayfs: workdir is in-use by another mount, mount with '-o index=off' to override exclusive workdir protection.\n");

		goto out;

	} else {

		pr_warn("overlayfs: workdir is in-use by another mount, accessing files from both mounts will result in undefined behavior.\n");

	}



	ufs->workbasedir = dget(workpath->dentry);

	err = 0;

out:

	return err;

}



static int ovl_get_upper(struct ovl_fs *ufs, struct path *upperpath)

{

	struct vfsmount *upper_mnt;



	upper_mnt = clone_private_mount(upperpath);

	if (IS_ERR(upper_mnt)) {

		pr_err("overlayfs: failed to clone upperpath\n");

		return PTR_ERR(upper_mnt);

	}



	/* Don't inherit atime flags */

	upper_mnt->mnt_flags &= ~(MNT_NOATIME | MNT_NODIRATIME | MNT_RELATIME);

	ufs->upper_mnt = upper_mnt;



	return 0;

}



static int ovl_get_workdir(struct ovl_fs *ufs, struct path *workpath)

{

	struct dentry *temp;
@@ -971,6 +919,58 @@ static int ovl_get_workdir(struct ovl_fs *ufs, struct path *workpath) 
	return 0;

}



static int ovl_get_workpath(struct ovl_fs *ufs, struct path *upperpath,

			    struct path *workpath)

{

	int err;



	err = ovl_mount_dir(ufs->config.workdir, workpath);

	if (err)

		goto out;



	err = -EINVAL;

	if (upperpath->mnt != workpath->mnt) {

		pr_err("overlayfs: workdir and upperdir must reside under the same mount\n");

		goto out;

	}

	if (!ovl_workdir_ok(workpath->dentry, upperpath->dentry)) {

		pr_err("overlayfs: workdir and upperdir must be separate subtrees\n");

		goto out;

	}



	err = -EBUSY;

	if (ovl_inuse_trylock(workpath->dentry)) {

		ufs->workdir_locked = true;

	} else if (ufs->config.index) {

		pr_err("overlayfs: workdir is in-use by another mount, mount with '-o index=off' to override exclusive workdir protection.\n");

		goto out;

	} else {

		pr_warn("overlayfs: workdir is in-use by another mount, accessing files from both mounts will result in undefined behavior.\n");

	}



	ufs->workbasedir = dget(workpath->dentry);

	err = 0;

out:

	return err;

}



static int ovl_get_upper(struct ovl_fs *ufs, struct path *upperpath)

{

	struct vfsmount *upper_mnt;



	upper_mnt = clone_private_mount(upperpath);

	if (IS_ERR(upper_mnt)) {

		pr_err("overlayfs: failed to clone upperpath\n");

		return PTR_ERR(upper_mnt);

	}



	/* Don't inherit atime flags */

	upper_mnt->mnt_flags &= ~(MNT_NOATIME | MNT_NODIRATIME | MNT_RELATIME);

	ufs->upper_mnt = upper_mnt;



	return 0;

}



static int ovl_get_indexdir(struct ovl_fs *ufs, struct ovl_entry *oe,

			    struct path *upperpath)

{
@@ -1008,6 +1008,55 @@ out: 
	return err;

}



static int ovl_get_lower_layers(struct ovl_fs *ufs, struct path *stack,

				unsigned int numlower)

{

	int err;

	unsigned int i;



	err = -ENOMEM;

	ufs->lower_layers = kcalloc(numlower, sizeof(struct ovl_layer),

				    GFP_KERNEL);

	if (ufs->lower_layers == NULL)

		goto out;

	for (i = 0; i < numlower; i++) {

		struct vfsmount *mnt;

		dev_t dev;



		err = get_anon_bdev(&dev);

		if (err) {

			pr_err("overlayfs: failed to get anonymous bdev for lowerpath\n");

			goto out;

		}



		mnt = clone_private_mount(&stack[i]);

		err = PTR_ERR(mnt);

		if (IS_ERR(mnt)) {

			pr_err("overlayfs: failed to clone lowerpath\n");

			free_anon_bdev(dev);

			goto out;

		}

		/*

		 * Make lower layers R/O.  That way fchmod/fchown on lower file

		 * will fail instead of modifying lower fs.

		 */

		mnt->mnt_flags |= MNT_READONLY | MNT_NOATIME;



		ufs->lower_layers[ufs->numlower].mnt = mnt;

		ufs->lower_layers[ufs->numlower].pseudo_dev = dev;

		ufs->numlower++;



		/* Check if all lower layers are on same sb */

		if (i == 0)

			ufs->same_sb = mnt->mnt_sb;

		else if (ufs->same_sb != mnt->mnt_sb)

			ufs->same_sb = NULL;

	}

	err = 0;

out:

	return err;

}



static int ovl_get_lowerstack(struct super_block *sb, struct ovl_fs *ufs,

			      struct path **stackp, unsigned int *stacklenp)

{
@@ -1077,55 +1126,6 @@ out_free_stack: 
	goto out;

}



static int ovl_get_lower_layers(struct ovl_fs *ufs, struct path *stack,

				unsigned int numlower)

{

	int err;

	unsigned int i;



	err = -ENOMEM;

	ufs->lower_layers = kcalloc(numlower, sizeof(struct ovl_layer),

				    GFP_KERNEL);

	if (ufs->lower_layers == NULL)

		goto out;

	for (i = 0; i < numlower; i++) {

		struct vfsmount *mnt;

		dev_t dev;



		err = get_anon_bdev(&dev);

		if (err) {

			pr_err("overlayfs: failed to get anonymous bdev for lowerpath\n");

			goto out;

		}



		mnt = clone_private_mount(&stack[i]);

		err = PTR_ERR(mnt);

		if (IS_ERR(mnt)) {

			pr_err("overlayfs: failed to clone lowerpath\n");

			free_anon_bdev(dev);

			goto out;

		}

		/*

		 * Make lower layers R/O.  That way fchmod/fchown on lower file

		 * will fail instead of modifying lower fs.

		 */

		mnt->mnt_flags |= MNT_READONLY | MNT_NOATIME;



		ufs->lower_layers[ufs->numlower].mnt = mnt;

		ufs->lower_layers[ufs->numlower].pseudo_dev = dev;

		ufs->numlower++;



		/* Check if all lower layers are on same sb */

		if (i == 0)

			ufs->same_sb = mnt->mnt_sb;

		else if (ufs->same_sb != mnt->mnt_sb)

			ufs->same_sb = NULL;

	}

	err = 0;

out:

	return err;

}



static int ovl_fill_super(struct super_block *sb, void *data, int silent)

{

	struct path upperpath = { };

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