ovl: split out ovl_get_upperpath() from ovl_fill_super() (6ee8acf0) · Commits · 戴 / test

fs/overlayfs/super.c

+35 −24

Original line number	Diff line number	Diff line
		@@ -827,6 +827,39 @@ static const struct xattr_handler *ovl_xattr_handlers[] = {
		NULL
		};

		static int ovl_get_upperpath(struct ovl_fs ufs, struct path upperpath)
		{
		int err;

		err = ovl_mount_dir(ufs->config.upperdir, upperpath);
		if (err)
		goto out;

		/* Upper fs should not be r/o */
		if (sb_rdonly(upperpath->mnt->mnt_sb)) {
		pr_err("overlayfs: upper fs is r/o, try multi-lower layers mount\n");
		err = -EINVAL;
		goto out;
		}

		err = ovl_check_namelen(upperpath, ufs, ufs->config.upperdir);
		if (err)
		goto out;

		err = -EBUSY;
		if (ovl_inuse_trylock(upperpath->dentry)) {
		ufs->upperdir_locked = true;
		} else if (ufs->config.index) {
		pr_err("overlayfs: upperdir is in-use by another mount, mount with '-o index=off' to override exclusive upperdir protection.\n");
		goto out;
		} else {
		pr_warn("overlayfs: upperdir is in-use by another mount, accessing files from both mounts will result in undefined behavior.\n");
		}
		err = 0;
		out:
		return err;
		}

		static int ovl_fill_super(struct super_block sb, void data, int silent)
		{
		struct path upperpath = { };
		@@ -870,30 +903,9 @@ static int ovl_fill_super(struct super_block sb, void data, int silent)
		goto out_free_config;
		}

		err = ovl_mount_dir(ufs->config.upperdir, &upperpath);
		if (err)
		goto out_free_config;

		/* Upper fs should not be r/o */
		if (sb_rdonly(upperpath.mnt->mnt_sb)) {
		pr_err("overlayfs: upper fs is r/o, try multi-lower layers mount\n");
		err = -EINVAL;
		goto out_put_upperpath;
		}

		err = ovl_check_namelen(&upperpath, ufs, ufs->config.upperdir);
		err = ovl_get_upperpath(ufs, &upperpath);
		if (err)
		goto out_put_upperpath;

		err = -EBUSY;
		if (ovl_inuse_trylock(upperpath.dentry)) {
		ufs->upperdir_locked = true;
		} else if (ufs->config.index) {
		pr_err("overlayfs: upperdir is in-use by another mount, mount with '-o index=off' to override exclusive upperdir protection.\n");
		goto out_put_upperpath;
		} else {
		pr_warn("overlayfs: upperdir is in-use by another mount, accessing files from both mounts will result in undefined behavior.\n");
		}
		goto out_unlock_upperdentry;

		err = ovl_mount_dir(ufs->config.workdir, &workpath);
		if (err)
		@@ -1196,7 +1208,6 @@ out_put_workpath:
		out_unlock_upperdentry:
		if (ufs->upperdir_locked)
		ovl_inuse_unlock(upperpath.dentry);
		out_put_upperpath:
		path_put(&upperpath);
		out_free_config:
		kfree(ufs->config.lowerdir);

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